A catalyst comprised of platinum, copper, selenium and halogen, composited with an inorganic oxide support or carrier, preferably alumina. The catalyst is one which possesses an intrinsically high activity, is stable and can operate at reforming conditions at high severities.

Catalytic reforming, or hydroforming, is a process well known to the petroleum refining industry for improving the octane quality of naphthas and straight run gasolines. In a typical process, a series of reactors are provided with fixed beds of catalyst which receive upflow or downflow feed, and each reactor is provided with a heater, or interstage heater, because the reactions which take place are endothermic. A naphtha feed, with hydrogen, or recycle gas, is cocurrently passed sequentially through the first reactor, a reheat furnace and then to the next reactor of the series. The vapor effluent from the last reactor of the series is a gas rich in hydrogen, which usually contains small amounts of normally gaseous hydrocarbons, from which hydrogen is separated from the C.sub.5.sup.+ liquid product and recycled to the process to minimize coke production; coke invariably forming and depositing on the catalyst during the reaction.
Reforming catalysts are recognized as dual functional, the catalyst composite including a metal, or metals, or a compound or compounds thereof, providing a hydrogenation-dehydrogenation (hydrogen transfer) function and an acidic component providing an isomerization function. The platinum group metals (ruthenium, osmium, rhodium, iridium, palladium and platinum), particularly platinum, have been widely used in commercial reforming operations, these metals being composited with an inorganic oxide base, particularly alumina; and in recent years promoters such as iridium, rhenium, germanium, tin, etc., have been added, particularly to platinum, to enhance one or more of certain of the characteristics which a good reforming catalyst must possess--viz., activity, selectivity, activity maintenance and yield stability. Halogen, e.g., chlorine, is generally added to provide the required acid function.
The principal reactions produced in reforming are dehydrogenation of naphthenes to produce the corresponding aromatic hydrocarbons; isomerization of n-paraffins to form branched-chain paraffins and isomerization of five membered to six membered ring compounds, and dehydrogenation of the latter to form aromatics; dehydrocyclization of paraffins to form aromatics; and hydrocracking of high molecular weight feed constituents to form lower molecular weight, or lower boiling, constituents, the net effect of these reactions being to increase the concentration of aromatics and isomers, with consequent octane improvement of naphthas boiling within the gasoline range. Hydrogenolysis, a specific and severe form of hydrocracking can also occur. This reaction which, inter alia, produces excessive amounts of methane and other hydrocarbon gases with decreased D.sub.5.sup.+ liquid yields can be particularly acute with multi-metallic catalysts.
In U.S. Pat. No. 2,851,399 which issued Sept. 9, 1958 to Brennan et al, there is disclosed a reforming catalyst containing platinum and selenium composited with alumina. In U.S. Pat. No. 3,884,799 to Mahoney et al, which issued May 20, 1975. there is also disclosed a catalyst, and process for using such catalyst for reforming a petroleum hydrocarbon fraction at conventional reforming conditions, which is constituted of a Group VIII noble metal, notably platinum, and rhenium and selenium composited on a refractory inorganic oxide, notably alumina, to which is added a halogen component, notably a chloride. This reference discusses the problem of hydrogenolysis which occurs in reforming during start-up with an unsulfided, or improperly sulfided, halogenated platinum-rhenium catalyst, and it discloses and claims the process of using a catalyst in reforming in which selenium is incorporated therein thereby reducing coke formation and eliminating any necessity of a pre-sulfiding treatment of that particular catalyst to suppress hydrogenolysis during start-up.
U.S. Pat. No. 4,151,115 by Paul E. Eberly, Jr. which issued Apr. 24, 1979, there is disclosed a reforming catalyst comprised of alumina and a Group VIII noble metal hydrogenation-dehydrogenation component, notably platinum, to which both iridium and selenium have been added to promote the activity and selectivity of the catalyst. The catalyst is prepared by a method wherein the selenium is introduced into and deposited throughout the support, and suitably the reforming catalyst contains a halogen component, particularly chlorine; and preferably the selenium component is introduced into the support, or catalyst, by impregnating same with a solution comprising selenium as an element, or a salt or compound thereof.
In copending Application Ser. Nos. 029,675 and 034,596, filed Apr. 13, 1979 and Apr. 30, 1979, respectfully, by Charles H. Mauldin et al, there are also disclosed catalysts, and method for the preparation of catalyst compositions comprised of platinum or platinum and palladium, rhenium, halogen, and preferably sulfur, composited with an inorganic oxide support, or carrier, to which a small concentration of copper is added to improve the yield and stability of the catalyst in reforming. Copper is an essential component of such compositions, it having been found that excessive C.sub.2.sup.+ hydrocarbon gas formation could be suppressed by the use of small and critical concentrations of copper; and that added benefits could be obtained by the further addition of sulfur to the catalyst to suppress hydrogenolysis.
It is nonetheless an objective of the present invention to provide a new and improved catalyst, and process for utilizing such catalyst for upgrading naphthas by reforming to produce higher octane gasolines.
A particular object is to provide a highly active catalyst, and process for effecting, at suitable reforming conditions, the production of high octane gasolines while minimizing hydrogenolysis and other type of hydrocracking which tend to produce methane and hydrocarbon gases of higher molecular weight than methane.
Another object is to provide catalyst which is capable of reforming feed of high sulfur level; the catalyst being particularly resistant to sulfur poisoning.
These and other objects are achieved in accordance with the present invention embodying a catalyst comprised of platinum, copper, selenium and halogen composited with an inorganic oxide support, or carrier, preferably alumina. The catalyst possesses an intrinsically high activity, and provides good yield and stability in reforming. The catalyst may also contain a sulfur component. p The catalyst is one which contains platinum as an essential component, generally in concentration ranging from about 0.1 percent to about 2 percent, preferably from about 0.2 percent to about 0.6 percent, based on the weight of the catalyst (dry basis).
The catalyst also contains copper as an essential component, generally in concentration ranging from about 0.01 percent to about 0.1 percent, preferably from about 0.025 percent to about 0.8 percent, based on the weight of the catalyst (dry basis). Preferably, the copper is composited with the catalyst in amount sufficient to provide an atom ratio of copper:platinum ranging from about 0.05:1 to about 1.54:1, preferably from about 0.12:1 to about 1.23:1. The copper component is conveniently added to the catalyst by impregnation. It is important that the concentration of copper on the catalyst be controlled to the proper level because high concentrations of copper acts as a poison and depresses catalyst activity.
Selenium is contained within the catalyst as an essential component, suitably in concentration ranging from about 0.001 to about 3 percent, preferably from about 0.01 to about 1 percent, based on the weight of the catalyst (dry basis). The selenium is incorporated into the catalyst at the time of its formation and preferably selenium is incorporated by impregnation of a solution of a soluble salt, acid or compound of selenium into the carrier. This can be carried out simultaneously with, prior to, or following the impregnation of the hydrogenation-dehydrogenation component, or other components, into the carrier. Selenium, in accordance with this invention, can be added to the carrier from a solution which contains both the salt, acid or compound of selenium, the hydrogenation-dehydrogenation component, or other components, and the inorganic acid such as HCl. Suitably, the salts or compounds are dissolved in a suitable solvent, preferably water, to form a solution, or each moiety is separately dissolved in a solution, the solutions admixed and the admixed solution used for impregnation of the carrier. The concentration of the salt or compound of selenium in the impregnation solution ranges from about 0.01 to 2 percent, preferably from about 0.01 to 1 weight percent, based on the weight of the solvent; this concentration being adequate to impregnate a sufficient amount of the selenium within the catalyst.
Halogen is an essential component, the halogen content of the catalyst generally ranging from about 0.1 to about 2.5 percent, preferably from about 0.7 to about 1.2 percent, based on the weight of the catalyst (dry basis).
Sulfur is a preferred, but not an essential component. The sulfur content of the catalyst generally ranges to about 0.2 percent, preferably from about 0.05 percent to about 0.1 percent, based on the weight of the catalyst (dry basis). The sulfur can be added to the catalyst by conventional methods, suitably by breakthrough sulfiding of a bed of the catalyst with a sulfur-containing gaseous stream, e.g., hydrogen sulfide in hydrogen, performed at temperatures of from about 350.degree. F. to about 1050.degree. F. and at pressures of from about 1 to about 40 atmospheres for the time necessary to achieve breakthrough, or the desired sulfur level.
The several components of the catalyst are composited with a refractory inorganic oxide support material, particularly alumina. Suitably, the copper is added first to the support, and subsequently the other components are added. The halogen component, particularly chlorine, is added along with the various components, or subsequent thereto, or both. The support can contain, for example, one or more of alumina, bentonite, clay, diatomaceous earth, zeolite, silica, activated carbon, magnesia, zirconia, thoria, and the like; though the most preferred support is alumina to which, if desired, can be added a suitable amount of other refractory carrier materials such as silica, zirconia, magnesia, titania, etc., usually in a range of about 1 to 20 percent, based on the weight of the support. A preferred support for the practice of the present invention is one having a surface area of more than 50 m.sup.2 /g., preferably from about 100 to about 300 m.sup.2 /g., a bulk density of about 0.3 to 1.0 g/ml, preferably about 0.4 to 0.8 g/ml, an average pore volume of about 0.2 to 1.1 ml/g., preferably about 0.3 to 0.8 ml/g., and an average pore diameter of about 30 to 300A.
The metal components can be composited or intimately associated with the porous inorganic oxide support or carrier by various techniques known to the art such as ion-exchange, coprecipitation with the alumina in the sol or gel form, and the like. For example, the catalyst composite can be formed by adding together suitable reagents such as a salts of the required metals and ammonium hydroxide or ammonium carbonate, and a salt of aluminum such as aluminum chloride or aluminum sulfate to form aluminum hydroxide. The aluminum hydroxide containing the salts can then be heated, dried, formed into pellets or extruded, and then calcined in air or other atmosphere. The metal hydrogenation-dehydrogenation components are preferably added to the catalyst by impregnation, typically via an "incipient wetness" technique which requires a minimum of solution so that the total solution is absorbed, initially or after some evaporation.
Suitably, the copper, and other metal components are deposited on a previously pilled, pelleted, beaded, extruded, or sieved particulate support material by the impregnation method. Pursuant to the impregnation method, porous refractory inorganic oxides in dry or solvated state are contacted, either alone or admixed, or otherwise incorporated with a metal or metals-containing solution, or solutions, and thereby impregnated by either the "incipient wetness" technique, or a technique embodying absorption from a dilute or concentrated solution, or solutions, with subsequent filtration or evaporation to effect total uptake of the metallic components.
In compositing the metals with the carrier, essentially any soluble compound of the respective metal can be used, but a soluble compound which can be easily subjected to thermal decomposition and reduction is preferred, for example, inorganic salts such as halide, nitrate, inorganic complex compounds, or organic salts such as the complex salt of acetylacetone, amine salt, and the like. In adding the copper, copper chlorides and nitrate are a preferred source of copper on the basis of availability, cost and effectiveness.
The copper is incorporated into the catalyst at the time of its formation, or thereafter, and preferably the copper is incorporated into the pre-formed carrier by impregnation from a solution of a soluble salt, or compound of copper; preferably in a solution of hydrochloric acid to provide good distribution of the copper. This step is carried out prior to the impregnation of the hydrogenation-dehydrogenation components. The copper, in accordance with this invention, can be added to the carrier from a solution which contains a salt, or compound of copper, and thereafter the copper impregnated support can be dried, calcined, and the hydrogenation-dehydrogenation components then added, suitably as salts or compounds dissolved in a suitable solvent, preferably water, to form a solution.
The impregnation of the platinum component, and other components, into a carrier is carried out by impregnating the carrier with a solution, or solutions, of the respective salts or compounds of the elements or metals to be incorporated. Salts, acids or compounds of each metal can be dissolved in a solution, or the salts, acids or compounds can be separately dissolved in solutions, the solutions admixed, and the admixed solution used for impregnation of the carrier. In other words, copper is added initially using conventional techniques, and then the other metals are added simultaneously or sequentially, suitably by impregnation. The amount of impregnation solution used should be sufficient to completely immerse the carrier, usually within the range from about 1 to 20 times of the carrier by volume, depending on the metal concentration in the impregnation solution. The impregnation treatment can be carried out under a wide range of conditions including ambient or elevated temperatures and atmospheric or supratmospheric pressures.
In a preferred embodiment of the present invention a carrier is impregnated with an aqueous halogen-acid solution of the copper. Exposure to a halogen acid can introduce substantially high levels of halogen into the carrier which is not desirable because subsequent metal impregnation is inhibited, and the catalyst can produce high acid cracking in reforming. However, excess halogen can be readily removed from the acid treated carrier by neutralization with ammonium hydroxide, suitably by contact at ambient temperature for periods ranging about 0.1 to about 1 hour, at strengths ranging from about 0.1 N to about 15 N, preferably from about 0.1 N to about 5 N. These treatments are followed by evaporation or filtration and then drying or calcination, or both, and then the metals impregnated catalyst can be further impregnated with a solution containing (1) a dissolved salt or compound of platinum, or platinum and additional metals, (2) a dissolved salt or compound of selenium, and (3) hydrochloric acid, followed by evaporation or filtration, with subsequent drying or calcination, or both, whereby the components are dispersed substantially uniformly to the inner part of the catalyst.
As suggested, a halogen component is also required. Fluorine and chlorine are preferred halogen components. The halogen is contained on the catalyst in concentration ranging from about 0.1 percent up to about 2.5 percent, preferably within the range of about 0.7 to about 1.2 percent, based on the weight of the catalyst. The introduction of halogen into catalyst can be carried out by any method and at any time of the catalyst preparation, for example, prior to, following or simultaneously with the impregnation of the platinum, copper and selenium components. In the usual operation, the halogen component is introduced simultaneously with the incorporation of these metal components. It can also be introduced by contacting a carrier material in a vapor phase or liquid phase with a halogen compound such as hydrogen fluoride, hydrogen chloride, ammonium chloride, or the like.
The catalyst, after impregnation, is dried by heating at a temperature above about 80.degree. F., preferably between about 150.degree. F. and 300.degree. F., in the presence of nitrogen or oxygen, or both, in an air stream or under vacuum. The catalyst is calcined at a temperature between about 500.degree. F. to 1200.degree. F., preferably about 500.degree. F. to 1050.degree. F., in the presence of oxygen in an air stream or in the presence of an inert gas such as N.sub.2 or in the presence of a mixture of O.sub.2 and inert gas. This calcination or activation is conducted for periods ranging from about 1 to about 24 hours in either flowing or static gases. Reduction is performed by contact with flowing hydrogen at temperatures ranging from about 350.degree. F. to about 1050.degree. F. for periods ranging from about 0.5 to about 24 hours at about 1-40 atm. The catalyst can be sulfided by use of a blend of H.sub.2 S/H.sub.2 and performed at temperature ranging from about 350.degree. F. to about 1050.degree. F. at about 1-40 atm. for a time necessary to achieve breakthrough, or the desired sulfur level. Post-sulfiding stripping can be employed if desired at conditions similar to those for reduction of the catalyst.
Treatment of the catalyst with a mixture of chlorine and oxygen can be substituted for air activation if desired. This procedure can correct for any possible maldistribution of the metals arising from improper impregnation, and the procedure is useful in restoring activity during regeneration-rejuvenation after on oil service. A blend of chlorine, oxygen and nitrogen can also be employed at temperatures ranging from about 350.degree. F. to about 1050.degree. F. for periods ranging from about 1 to about 24 hours at 1-40 atm. Treat times for these various operations are a function of gas flow rates, gas compositions, and conditions. The catalyst halide content can be controlled during impregnation, or adjusted by treatment with water or water-hydrogen chloride blends.
This catalyst can be used in semi-regenerative, cyclic, semi-cyclic, or continuous bed reforming. It is particularly useful in cyclic reforming operations. The catalyst is particularly useful at severe reforming conditions, especially at low pressures, or pressures ranging from about 50 psig to about 150 psig, where maximum yield is favored.
The feed or charge stock can be a virgin naphtha, cracked naphtha, a Fischer-Tropsch naphtha, or the like. Typical feeds are those hydrocarbons containing from about 5 to 12 carbon atoms, or more preferably from about 6 to about 9 carbon atoms. Naphthas, or petroleum fractions boiling within the range of from about 80.degree. F. to about 450.degree. F., and preferably from about 125.degree. F. to about 375.degree. F., contain hydrocarbons of carbon numbers within these ranges. Typical fractions thus usually contain from about 20 to about 80 Vol.% paraffins, both normal and branched, which fall in the range of about C.sub.5 to C.sub.12, from about 10 to 80 Vol.% of naphthenes falling within the range of from about C.sub.6 to C.sub.12, and from 5 through 20 Vol.% of the desirable aromatics falling within the range of from about C.sub.6 to C.sub.12.
The reforming runs are initiated by adjusting the hydrogen and feed rates, and the temperature and pressure to operating conditions. The run is continued at optimum reforming conditions by adjustment of the major process variables, within the ranges described below:
______________________________________ Major Operating Typical Process Preferred Process Variables Conditions Conditions ______________________________________ Pressure, Psig 50-750 100-300 Reactor Temp., .degree.F. 750-1100 850-1000 Gas Rate, SCF/B 1500-10,000 2000-7000 (Incl. Recycle Gas) Feed Rate, W/Hr/W 0.5-10 1-3 ______________________________________


Methods for power factor correction (PFC) and for reducing conduction losses and switching losses in a power converter as well as the power converter and phase management circuitry for the power converter. The power converter includes a first PFC pre-regulator interleaved with at least one additional PFC pre-regulator, and a step down converter. The average input power is measured downstream of the front end at the step down converter and the average current sense signal is compared to a reference voltage. Each additional PFC pre-regulator is disable when output power generated by the front end is less than a first pre-designated rated power level and each additional PFC pre-regulator is enabled when the output power is greater than a second pre-designated rated power level.

Interleaved power factor correction techniques are being used, primarily, to reduce conduction losses in connection with power factor correction (PFC) pre-regulators and to increase power densities by reducing total inductor magnetic volume. Interleaving PFC pre-regulators, in which two or more PFC pre-regulators are operated out-of-phase, is commonly employed in applications such as—for the purpose of illustration and not limitation—power supplies for personal computers, computer server power supplies, and in industrial AC to DC power conversion.
Efficiency improvements using interleaved techniques, however, are only observed at higher power levels where conduction losses dominate over switching losses. However, this technique increases parasitic switch/field-effect transistor (FET) capacitance, which increases switching losses and reduces light load efficiency.
For example, referring to FIG. 1, a typical AC to DC converter 10 with interleaved PFC pre-regulators includes a first stage (Stage 1) structured and arranged to provide interleaved PFC AC to DC conversion and a second stage (Stage 2) structured and arranged to provide DC to DC conversion. The first stage includes a first PFC pre-regulator 12 (Phase 1) and at least one additional PFC pre-regulator 14 (Phase 2) that are interleaved. The number of additional pre-regulator 14 is related to the number of desired phases. Hence, a two phase system (as shown in FIG. 1) will have a first PFC pre-regulator 12 (Phase 1) interleaved with a second PFC pre-regulator 14 (Phase 2); while and a three phase system (not shown) will have a first PFC pre-regulator 12 interleaved with a second PFC pre-regulator 14 and with a third PFC pre-regulator (not shown).
The interleaved PFC pre-regulators 12 and 14 are adapted to provide AC to DC power conversion. Each of the interleaved pre-regulators 12 and 14 is structured and arranged to include an inductive element L1 and L2 and a current blocking device, such as diode D1 and D2. Those of ordinary skill in the art can appreciate that other means of blocking current besides diodes can be used.
In pertinent part, each of the interleaved PFC pre-regulators 12 and 14 further includes a switching device 13 and 30, which is shown as field effect transistors (FETs) Q1 and Q2, and a gate driving device 11 and 28. The gate driving devices 11 and 28 are adapted for opening, i.e., turning OFF, and closing, i.e., turning ON, the corresponding gates of the switching devices 13 and 30. Those of ordinary skill in the art can appreciate that other switching device types can also be used.
The front end (AC to DC conversion) stage (Stage 1) of the power converter 10 is generally followed by a second downstream (DC to DC conversion) stage (Stage 2). The second stage includes a peak current mode controlled step down converter 16, such as a step down converter, a fly-back converter, and the like, that is adapted to step down the regulated boost voltage (VBOOST) to a more usable voltage. The step down converter 16 includes a transformer 19, a current sense resistor 17, and a switching device 15. For simplicity, efficient operation of the step down converter 16 can be controlled using peak current mode control techniques that are known to the art.
A problem with this configuration, however, is that, at lighter power loads, conduction losses are negligible and switching losses dominate. Recalling that, heretofore, interleaving PFC pre-regulators have been used to reduce conduction losses, traditional interleaving of PFC pre-regulators 12 and 14 reduces efficiency at lighter power loads.
To improve efficiency at these lighter power loads and to reduce switching losses, it would be desirable to provide means and methods for selectively turning OFF the second PFC pre-regulator 14 and any other PFC pre-regulators (not shown) during instances of lighter power loads and turning ON or leaving ON the additional PFC pre-regulator(s) 14 during instances of higher power loads.

Interleaved power factor correction pre-regulator phase management circuitry


An air conduit arrangement for ventilating or air conditioning of a vehicle interior, which is supplied with multi-layered, preformed panel elements.. In this arrangement, the air conduits are bordered in the area of the panel elements by two wall sections which are glued together in a permanently resilient manner by means of a connecting flange. Of these, respectively one wall section is formed by the panel element itself and the other wall section by a separate thermoplastic preformed part disposed on the back of the panel element.

The invention relates to an air conduit arrangement for ventilating or air conditioning a vehicle interior, which is supplied with multi-layered, preformed panel elements (10), wherein a decorated side (12) of the panel elements (10) faces the vehicle interior and a back (14) with fastening elements faces the body wall.
Air conduit arrangements, through which fresh air or conditioned air is brought to individual passengers seats, are already being employed in vehicles with large interiors, such as ships, aircraft or buses. In most cases there are outlet openings in the ceiling panels above the seats, to which flexible hoses are brought from a central ventilation or an air conditioner. In these case the hoses are disposed hidden behind the paneling.
In smaller vehicles, in particular passenger cars, the outlet openings for air or conditioned air are located in the dashboard. Here, too, the air conduits can be embodied in the form of hoses, which are attached hidden behind the frame of the dashboard, or they can be molded as thermoplastic preformed parts which are friction-welded to other thermoplastic preformed parts of the frame of the dashboard. However, the dashboard does not represent a panel element, but a functional element.
To make it possible in small vehicles, for example mini buses, to provide a better supply of air or conditioned air to the seats, it would be desirable to supply it via air conduits to openings in the paneling, such as is known in connection with the above mentioned vehicles with large interiors. However, in this case there is the problem that to provide within comparatively small exterior dimensions as spacious as possible an interior, the panel elements are attached very closely to the body, because of which the space remaining between them is very narrow. Thus, in most cases it is not possible to house air conduit arrangements of the previously discussed type which would still fit into the space between the panel elements and the body.

Air conduit arrangement for the ventilation or air conditioning of the interior of a vehicle and method for producing an air conduit arrangement


A solar powered rechargeable street light, which can be networked to a system. The modular and tamper resistant street light and system can be used with individual street lights or a network of street lights. The system can be powered from a central controller, which can detect tampering by individuals or harsh weather conditions.

A need exists for a solar powered rechargeable street light and system that can be used individually or powered from a central controller for security purposes, such as in a prison area, or in an area known for crime, such as vandalism and theft.
A need exists for a solar powered rechargeable street light and system that can be quickly installed, with no welding, easily transported down a roadway without the need for special permits, and have replaceable components.
A further need exists for a solar powered rechargeable street light and system that has a robust photovoltaic frame which can withstand sandstorms and impact of high velocity particulate without shutting down.
The present embodiments meet these needs.
The present embodiments are detailed below with reference to the listed Figures.

Solar powered rechargeable street light with tamper resistant networkable system


An apparatus and method for extending the service area in a mobile communication system is provided, in which the service area is defined with a normal mode or an extension mode based on a distance between the base station and the mobile station and, in case of the extension mode, a transmission clock used by the mobile station for transmitting signals is changed, thus extending the service area. The access is attempted in the normal mode, and the transmission clock for transmitting the mobile signal is advanced the initial delay in the extension mode when the access fails. The access is reattempted with repeating the control of the transmission clock until the number of times of the access attempt reaches a predetermined number of times. When the number of times of the access currently attempted is greater than the predetermined number of times, the extension mode is converted to the normal mode, returning to the initial state.

1. Field of the Invention
The present invention relates to the extension of the service area in a code division multiple access (CDMA) mobile communication system and, more particularly, to an apparatus and method for extending the service area in a mobile communication system, in which the service area is defined with a normal mode or an extension mode based on a distance between the base station and the mobile station and, in case of the extension mode, a transmission clock used by the mobile station for transmitting signals is changed, thus extending the service area.
2. Discussion of Related Art
In general, all the base stations of a digital mobile communication system (digital cellular mobile communication system or personal communication system) employing CDMA mode synchronize with the CDMA system reference time. Its mobile stations also synchronize with the CDMA system reference time using time information supplied by the base stations. Here, the base station acquires the system reference time using the GPS time while the mobile station synchronizes with the base station using the time information transmitted therefrom. Accordingly, the reference time of the mobile station is delayed by the propagation delay time during which the time information is sent from the base station to the mobile station. The degree of this delay depends on the relative distance between the mobile and base station and surrounding environments.
The mobile station uses an access channel to have access the base station system located in a corresponding coverage area. The access channel is composed of access channel slots and used when the mobile is registered to the base station through the backward channel or requires a call. Here, a single access channel slot is allocated for a single access channel message transmission. This access channel message consists of four frames (20 ms) minimum to twenty-six frames maximum based on its length, and uses an appropriate value according to systems. The access channel message transmits a message frame, being synchronized with the point of time at which the slot starts, and sends the next message frame after the slot starts. Thus, the boundary of the access channel slot coincides with that of the frame.
Meanwhile, the mobile transmits an origination message using the access channel when it attempts to have access the base station system located in the coverage area. At this time, a single access channel slot is used for a single origination message transmission. The origination message includes information on the mobile (mobile device number, mode indicating whether the mobile is in the CDMA dedicated mode or dual mode, and class indicating whether the device is the PCS or cellular phone) and terminating numbers. When the mobile receives the acknowledge, for the origination message transmitted through the access channel, from the base station system within a predetermined period time, the attempt to have access the system is successively terminated. However, when the mobile does not receive the acknowledge from the system within the predetermined period of time, it retransmits the origination message and waits for the acknowledge. If the mobile did not acquire the acknowledge again, it attempts to retransmit the origination message one more time. The number of times of retransmission is predetermined (it is decided by the sum of Num_Step and Max_Req_Seq in the access parameter message sent from the base station to the mobile station) and, if the mobile does not receive the acknowledge from the system even when it performs retransmission a predetermined number of times, the attempt to access the system is finished, being failed.
Accordingly, the base station continuously monitors the access channel because it does not know when the mobile attempts the access. Here, it is inefficient to search for the access signal continuously because the mobile transmits the message using the access channel slot, and it is the most efficient for capture of the signal from the mobile to search for the access signal from the mobile within a predetermined period time during which the access signal can arrive at every frame boundary of 20 ms. The period of time during which the base station search for the access signal sent from the mobile is called xe2x80x9csearch windowxe2x80x9d. This search window is determined with regard to the propagation delay according to the service area of the base station and the basic processing delay, the service area of the base station being decided at the stage of designing and optimizing the base station. The service area of each base station can be appropriately adjusted according to surrounding environments, neighboring base stations or population density. For example, the service area is defined small (for instance, 1-3 km approximately) when the base station is located in an area where population density is higher and there are lots of neighboring buildings, while it is decided wide (for instance, 20-30 km approximately) when the base station is placed in an area where the population density is lower and there is barely building.
Meantime, the period of time during which the access signal of the mobile can arrive at the base station is calculated as below. The period of time during which the access signal can reach the base station becomes the minimum when the mobile is placed right next to the base station (when there is no aerial propagation delay) This period of time corresponds to the sum of the transmission delay of the base station, the processing delay of the mobile and the reception delay of the base station. Furthermore, the period of time during which the access signal can arrives at the base station becomes the maximum when the mobile is located at the outmost region of the service area of the base station. This period of time corresponds to the sum of the minimum period of time and double of the aerial propagation delay. Here, the aerial propagation delay is doubled because the mobile sends the signal to the base station on the basis of the time information of the base station. The actual period of time that the mobile acquired corresponds to the delay time between the base station and the mobile. Accordingly, the period of time during which the signal reaches the base station when the mobile attempts to have access it should be the sum of the delay time during which the time information is sent to the mobile from the base station and the delay time during which the signal is transmitted from the mobile to the base station. This is the reason why the aerial propagation delay is also called the round trip delay (RTD).
Meanwhile, when the mobile sends the originating message, the preamble as many as numbers decided by its operator is transmitted first, and the base station channel element starts demodulation using this preamble. Here, the maximum allowable delay in the mobile signal sent to the base station is determined according to the size of the window set in the base station. When the preamble is searched, for instance, the search is carried out from the place distant from the system time (access channel slot) by preamble_PN_offset to preamble_window_length+preamble_PN_offset in response to Half PN chip. Accordingly, the base station sets PN offset to the maximum correlation value among correlation results as many as (preamble_window_length)/4.
However, the aforementioned conventional mobile communication system cannot process a signal having a delay of two Walsh symbols or more in terms of the chip characteristic of cell site modem (CSM). That is, when the signal from the mobile arrives at the base station, being delayed more than two Walsh symbols, the base station cannot receive the signal. Here, the delay of two Walsh symbols means an area where the basic communication can be actually carried out.
Accordingly, the present invention is directed to an apparatus and method for extending the service area in a mobile communication system that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide an apparatus and method for extending the service area in a mobile communication system, in which the service area is defined with a normal mode or an extension mode based on a distance between the base station and the mobile station and, in case of the extension mode, a transmission clock used by the mobile station for transmitting signals is changed, thus extending the service area.
To accomplish the object of the present invention, there is provided an apparatus for extending the service area in a mobile communication system, comprising: means for generating a clock required for receiving a signal from a base station and transmitting a signal from a mobile station; means for receiving the signal transmitted from the base station; and means for variably controlling the clock generated by the clock generating means according to the signal received by the receiving means, and sending the controlled clock to means for transmitting the signal from the mobile station.
The normal mode is an operation mode in case that the distance between the base station and mobile station is included in a basic coverage area, and the extension mode is an operation mode in case that the distance between the base station and mobile station is not included therein.
To accomplish the object of the present invention, there is also provided a method for extending the service area in a mobile communication system, wherein a method of accessing a base station of a CDMA mobile communication system comprises: a first step of attempting access in the normal operation mode; a second step of performing a predetermined following operation when the access is successful, and converting the operation mode to the extension mode when the access fails; a third step of varying a transmission clock by a predetermined level after the operation mode is converted to the extension mode, and attempting the access again; and a fourth step of carrying out a predetermined following operation when the access is successful in the third step, converting the operation mode to the normal mode when the access fails after the access is attempted a predetermined number of times and returning to the initial state.
The third step comprises the substeps of: controlling the mobile signal transmitting clock to be advanced by the initial delay time; reattempting the access with the controlled transmission clock, and comparing the number of times of that access attempts that have been made so far with a predetermined number of times of access attempt when the access fails; controlling the transmission clock to be advanced by a predetermined level by steps when the number of times of the access attempts that have been made so far is less than the predetermined number of times, and then reattempting the access with the controlled transmission clock; and repeating the control of the transmission clock""s level and access attempt until the number of times of the access attempts becomes the predetermined number times when the reattempted access fails.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Apparatus and method for extending service area in mobile communication system


An interface apparatus capable of appropriate connection with external devices having various specifications. Control signal DRVSEL is used for setting output method of a signal from output circuit 801 to an open-collector drive or a totem-pole drive. 3-State buffer 904 which drives a communication path comes into high-impedance status when its enable input is at a H level, on the other hand, when the enable input is at a L level, drives its output with the same logic as that of AND gate output. When the signal DRVSEL is at the L level, the 3-state buffer 904 drives the output only when its internal signal is at the L level, thus output is made in the open-collector drive. On the other hand, when the signal DRVSEL is at the H level, the 3-state buffer 904 drives the output with the same logic as that of its internal signal, thus output is made in the totem-pole drive.

This invention relates to an interface apparatus and method and an image output apparatus having the interface apparatus and, more particularly to an interface apparatus for transmitting/receiving information with an external apparatus via a communication line, a method for negotiating for transmitting/receiving information between apparatuses, and an image output apparatus having the interface apparatus.
Generally, a printer and an information processing device are connected via a fixed type communication interface. In each device, an open-collector type interface circuit or totem-pole type interface circuit is fixedly provided, and it is impossible to select an interface circuit in accordance with the specification of communication destination device.
However, in a case where a device has only an open-collector type interface circuit, even if another device as a communication destination uses a totem-pole type interface, high-speed communication cannot be performed. In an open-collector type interface circuit, a transitional period where a signal level changes from a high level to a low level, and a transitional period where the signal level changes from the low level to a high level are greatly different. Especially, the transition of signal level from the low level to the high level is made very slowly.
In a case where the device has only a totem-pole type interface circuit, if the power of the communication destination device is turned off and the communication line is in short-circuit or in low-impedance status, overcurrent occurs, which consumes a large amount of electricity and may cause the interface circuit to generate heat.
There is a tendency of signal voltage swing to be complicated, since small signal voltage swing is used to increase communication speed or to save electricity. A device corresponding to only one signal voltage swing cannot handle communication with devices of various specifications. In many cases, the input characteristics of signals and the output characteristics of signals do not coincide with each other.
Further, even though the device can communicate with a high-performance device, if the device cannot communicate with existing devices, it cannot be efficiently utilized. For example, it is inconvenient that every time a new device is introduced, all the devices to be connected to the new device must be changed.

Apparatus for communicating via an interface using a drive method selected by information received by the interface


A lever latch secures a door panel of a cabinet or the like in a closed position relative to the frame. The lever latch is installed within an aperture formed in the door, and releasably retains the door against the frame when the door and the frame are latched together. The lever latch includes a housing for mounting in the door, a handle assembly which is pivotally attached to the housing, and rotatable between an opened and closed position, and a fastening member. The fastening member retains the door, when the door is closed against the frame, by engaging the frame as the handle assembly is rotated to the closed position. The housing, handle assembly and fastening member form an integral solid structure for preventing the passage of matter through the latch itself. The lever latch further includes a biasing member which is adapted to retain the handle assembly in the closed position, urge the handle assembly from the closed position to the opened position upon disengagement and provide initial accelerated movement to the handle assembly toward the opened position upon disengagement thereof. A trigger is also included for latching the handle assembly in the closed position, and unlatching the handle assembly from the closed position for movement to the opened position. The trigger which is integrally disposed within the central vicinity of the handle assembly provides increased mechanical advantage during the closing thereof.

1. Field of the Invention
The present invention relates generally to latching devices and more particularly to lever latches for fastening hinged doors, panels and the like.
2. Brief Description of the Prior Art
Various types of latching devices for fastening doors, panels and the like are known.
Some types incorporate a spring to bias a latch bolt into a latched position about a keeper. Rotary handles are provided so that the latch bolt may be rotated away from the keeper in opposition of the spring, and into an unlatched position. However, the handle of such a latch which extends beyond the body may cause inadvertent latching and unlatching in response to impact forces.
Another type are "trigger release lever" latches which incorporate a handle in combination with a trigger in order to compress an arm and a stop against an inner surface of a cabinet frame. The handle and trigger when latched are positioned substantially flush with the outer surface of the door which prevents inadvertent unlatching from the latched position. A housing is included to which the handle is rotatably connected and the trigger of such latches is pivotally connected either to the housing or to the handle. In U.S. Pat. No. 4,693,503, an example of a trigger release lever latch is shown comprising a flanged housing, a handle and a trigger which are inserted within an opening in a cabinet door or the like.
One problem associated with such prior art trigger release lever latches is that a plurality of spring devices are required in order to provide proper function of the latch. For example, in latches where the trigger is pivotally connected to the housing, two springs are required in order to provide proper function. Furthermore, in such latches that provide the trigger as a pivotal part of the handle, two springs, or in some cases three springs, are utilized for proper latch operation. In particular, one spring is used which forces the trigger into the closed position, another moves the handle into the opened position upon release of the trigger, and a third gives the handle an initial rise immediately after trigger release which prevents the trigger from snapping back into the latched position.
Another problem with such prior art trigger release lever latches is that dirt, water and other matter is able to pass through the latch and into the interior compartment of the cabinet, thus causing damage to the equipment contained therein. A latex boot is oftentimes utilized which covers the back of the latch, however, this only provides partial sealing for the latch.
The present invention has been developed in view of the foregoing to overcome the deficiencies of the prior art.


Apparatus for inserting full bore tools into an earth borehole, such as oil and gas wells, includes: a blowout preventer assembly superimposed on the wellhead of the borehole; a seal body having an internal concentric seal diameter, superimposed on the blowout preventer assembly; a tubular mandrel concentrically engaged with the seal diameter of said seal body, with a standpipe attached thereto; a tubular bell nipple connected to the seal body; and a pack-off assembly disposed between the internal diameter of the standpipe and a workstring inserted into the earth borehole.. The blowout preventer assembly, seal body, and bell nipple are typically installed on the wellbore when well operations commence. During ordinary, unpressurized wellbore operations a seal diameter protector may be installed in the seal body. When wellbore pressure is present or may be expected (such as operations conducted during underbalanced conditions), the seal diameter protector is removed, the tubular mandrel and standpipe sealingly engaged with the seal diameter of the seal body, and a pack-off assembly installed between the internal diameter of the standpipe and the workstring. The tubular mandrel and standpipe internal diameters are at least as large as the bore of the wellbore, permitting introduction of full bore tools into the wellbore. As no part of the apparatus extends into the blow-out preventer stack, there is no loss of blow-out preventer redundancy while using the apparatus.

1. Field of the Invention
The invention relates to an apparatus providing a means for inserting a workstring into an earth borehole. With additional particularity, the invention relates to apparatus for passage of well tools from the surface of the earth into an earth borehole which is pressurized or may become pressurized during operations being conducted with the well tools. With greater particularity, the invention relates to a means for passage of full sized tools, that is, tools with outer diameters as large as the inner diameter of the borehole, into a pressurized or potentially pressurized earth borehole, without loss of pressure control, without the use of either the blind or annular blow-out preventers to prevent loss of pressure control, and without loss of redundant blow-out preventer protection in the event of an emergency condition. Such apparatus have particular, but not exclusive, utility in the fields of oil and gas exploration and production where highly pressurized flammable fluids may be encountered in the wellbore during various operations.
2. Description of the Prior Art
In the practice of drilling earth boreholes, subsurface pressures are most frequently controlled by the hydrostatic pressure of the wellbore fluid column, typically comprising drilling mud or completion fluid. As long as the hydrostatic pressure created by such wellbore fluid column is at least as great as the subsurface formation pressure, no formation fluid may flow into the borehole. However, situations arise where the subsurface formation pressure is greater than the hydrostatic fluid column pressure. This may be unintentional, where unexpectedly high subsurface pressures are encountered during well operations, or intentional, where an oil or gas zone to be produced is intentionally perforated in an "underbalanced" mode in order to prevent wellbore fluids, containing solid particulates, from flowing into the oil and gas zone and potentially damaging the ability of said zone to produce minerals. In other drilling, completing, or workover operations on an oil or gas well, it is often necessary to introduce workstrings (such as wireline, coiled tubing, or snubbing strings) conveying various tools (such as logging tools, perforation tools, nitrogen injection tools, etc.) into the wellbore under pressure, or at least when pressure conditions present a substantial risk of occurring. In situations where wellbore fluid pressure is insufficient to control fluid flow from a pressure bearing subsurface formation, alternative means must be relied on to control the subsurface pressure; the safety of the rig personnel, rig equipment, and the rig itself depend on this pressure control. The ability to control subsurface pressure is also critical to prevent the loss of valuable natural resources, such as oil and natural gas, and to prevent environmental pollution resulting from an uncontrolled fluid flow.
During normal drilling operations the weight of the wellbore fluid is typically adjusted ("weighted up") to produce wellbore hydrostatic fluid pressure that is higher than any formation pressure encountered, therefore the only surface equipment used to control wellbore pressure is a "blow-out preventer" assembly. Typically two different types of independently operable blow-out preventers are included in series, to provide a redundant safety system. One type of preventer typically included in a blow-out preventer assembly is an annular type which is capable of closing off the wellbore while no workstring is in the well; in addition, the annular preventer will close and seal around a workstring in the wellbore, without damaging the workstring. Another type of blow-out preventer typically included in a blow-out preventer assembly is a "blind" or "blind/shear" type, capable of completely closing the wellbore at the surface while no workstring is in the wellbore, or if a workstring is in the wellbore, sealing the well while crushing and/or shearing any pipe, wireline, or tubing that may be in the wellbore. Blind or blind/shear blow-out preventers are not capable of sealing a pressurized wellbore while at the same time allowing pipe, wireline, or tubing to be passed into the well, and annular blow-out preventers are subject to damage if used in this mode.
Rather, apparatus used to allow sliding passage of pipe, wireline, or tubing while simultaneously maintaining pressure seal of a wellbore are typically referred to as "pressure lubricators". While no representation is made thereto, the name of such equipment presumably emanates from the fact that some form of lubrication is typically applied at the sliding interface of the seal and wire or tubular being passed therethrough.
One conventional pressure lubricator configuration, such as disclosed in U.S. Pat. No. 4,836,289 to Young, includes an extended tubular with a flared lower end. The flared end of said tubular is lowered into the wellbore and the annular blowout preventer closed about the outer diameter of said tubular, to both hold it in place and to provide a lower pressure seal. A lock pin mandrel is installed atop the blowout preventer assembly, and lock pins in that mandrel are advanced into a mating profile on the tubular to further secure the tubular in place. The lock pins and the flared tubular end, when contacting the annular preventer element, prevent the tubular from being forced out of the well due to pressure from below. The annular blowout preventer necessarily must remain closed about this type of lubricator during operations therethrough. Disadvantages to this conventional design are several: the outer diameter of the tubular must be smaller than that of the inner diameter of the annular blowout preventers, thereby limiting the size of tools that may be inserted into the well, and use of the annular blow-out preventers to provide a lower lubricator pressure seal effectively disables that blow-out preventer from preventing escape of pressure at the top of the lubricator assembly, forcing reliance in such event solely on the blind or blind/shear rams, use of which will damage pipe, wireline or tubing extending therethrough when the blind rams are closed. Accordingly, by using the annular blow-out preventer to provide a pressure seal about the lubricator, not only is redundance of critical safety equipment lost, but use of the safety equipment which remains is likely to cause property damage. In addition, rig personnel must climb up on the blowout preventer and wellhead assembly or on scaffolding to manually access and advance the lock pins. This procedure is inherently unsafe.
Another type of lubricator assembly is disclosed in U.S. Pat. No. 4,553,591 to Mitchell, Nov. 19, 1985. In Mitchell a dual flanged spool is mounted between the annular blowout preventer and the bell nipple, a cylindrical wear bushing having an axial bore secured therein by radial pins, and a mandrel having an internal diameter less than the blow-out preventer bore diameter connected to the axial bore of the cylindrical bushing. The size of wireline tools that may be used with this mandrel in place is restricted, since Mitchell teaches that the internal diameter of the mandrel is less than the blowout preventer bore diameter in order to prevent "whipping" of pipe, wireline or tubing in the blowout preventers. Further, multiple lockdown pins must be manually advanced in the annular spool to engage the mandrel and cylindrical wear bushing. To advance the pins, one or more drilling rig personnel typically climb upon the blow-out preventer stack or make-shift boards and scaffolding placed around same, which may be at a great distance above ground or water level and too often presents a difficult, slippery, muddy surface to climb upon.
Neither of the aforesaid patents provide apparatus and method for providing a wellbore pressure seal which provide the advantages of:
i) having a full-bore inner diameter, at least as large as the wellbore diameter, so as to permit maximum workstring tool size passage therethrough; PA1 ii) having a pressure seal at the lower end of the pressure control apparatus independent of the annular or ram-type blowout preventer, thereby retaining redundant blow-out prevention capability; and PA1 iii) being able to be installed entirely from the rig floor without removing existing equipment, thereby saving time and avoiding the necessity of rig personnel to climb upon and about the blowout preventer stack to manually advance lockdown screws or the like. PA1 1. a blowout preventer assembly comprising a blind and/or blind/shear ram and an annular blow-out preventer superimposed thereon; PA1 2. a single flanged seal body having internal concentrically disposed axial threads and seal surfaces, superimposed on the annular blow-out preventer; PA1 3. a bell nipple sealingly engaged with the seal body; PA1 4. a tubular mandrel sealingly engaged with the inner threads and seals of the seal body, the mandrel having one or more standpipe sections extending upwardly therefrom; PA1 5. a protector for the inner threads and seal surfaces of the single flanged seal body; PA1 6. a tool for running and retrieving said protector; PA1 7. means for forming a pressure seal between the inner diameter of said mandrel or standpipe and a workstring slidably disposed therein, superimposed at the top of the mandrel/standpipe assembly.
The invention disclosed herein represents a significant improvement over existing lubricator stack assemblies in that all of the aforesaid advantages, in combination, are embodied therein in an economically deployed, safe apparatus having few components.

Apparatus for insertion of full bore tools into an earth borehole


The invention includes a method for collecting radiation. An electromechanical radiation collection device is disposed in a roll to collect radiation directed at the roll. The invention is also an apparatus comprising a roll having an outer surface. An electromechanical radiation collection device is disposed in the roll.

The invention is a radiant energy collection device. More specifically, the invention is a roll based radiant energy collection and measuring device for use in a process line.
Processing systems using radiant energy sources are known in many industrial processes. One exemplary processing system uses ultraviolet (UV) lamps or bulbs placed near a product in a manufacturing line to cause chemical reactions to occur in or on the product. Often these chemical reactions are referred to as curing (or in some industries as drying). The wavelengths of radiant energy radiated by UV lamps in both the visible and the non-visible spectrum have been found to be particularly effective in transferring energy to the product to effect the desired chemical changes.
The energy wavelengths radiated onto the product typically range from approximately 2.5 micrometers to approximately 190 nanometers. The product being processed by the system can be almost anything, but typically it is a "web" of paper, plastic, or paper-like material (e.g., paperboard). The "web" comprises a continuous stream of material fed through a series of rollers. Radiant energy sources (typically more than one lamp or bulb) are placed at various points along the web to radiate energy onto the web. One or more coatings on the surface of the web, or the web material itself, are caused to undergo a chemical change during this process. In this manner the coating on the web (e.g., ink, lacquer, or adhesives) or the web itself is cured.
Unfortunately, the performance of an individual UV energy lamp (or any other energy source) can vary. A newer lamp may radiate energy more intensely than when it is older. Individual lamps with the same specifications can perform differently. Individual lamps may also perform differently along their length. Specifically, different wavelengths may be emitted more intensely from one lamp to the next. As would be expected, as a lamp grows older, its performance typically declines until it ultimately fails. The power provided to the lamp can also affect the lamp performance. If the electrical service to the lamp fluctuates, specific wavelengths produced by the lamp may vary in intensity. Differences in air temperature surrounding the lamp as well as the time it takes for the lamp to warm up may also cause fluctuations in wavelength intensity. All these variances in the intensity of the radiant energy emitted by the lamp can cause the level of curing of the web to vary. Therefore, in order to optimize the process and provide consistent product it is necessary to monitor the amount of radiant energy emitted by the lamp in order to assure proper curing (i.e., radiation exposure as a function of intensity and exposure time) of the web.
To measure the amount (or "dose") of radiant energy impinging on the web, a detection system is needed. One previous method to evaluate whether the source was providing adequate radiant energy was to test the web downstream from the lamp. Although this gave a very accurate measurement of whether the web had been properly cured, the measurement took place too late in the process, since product which had not been properly cured could not be used, and was thus discarded.
An alternate measurement method was to use electronic devices such as compact integrating radiometers (known in the art) placed on the web and moved with the web between the lamp and the web to provide a test measurement of the amount of radiant energy being emitted by the lamps. While this method gave a more direct measurement of lamp performance, it was performed during setup and not during actual production so that no information was being gathered as to energy impinging the web during the actual run time process. In particular, no measurements of variances in the radiant energy impinging the web were able to be taken. Once again, improperly cured product resulted. Additionally, passing the web through nip points and idler rolls, as is required in some casting processes, could damage the compact integrating radiometers before measurements could be obtained.
Another alternative method was to use actinometric devices to measure the amount of radiation. An actinometric device's chemical composition changes as it is exposed to radiation. Examples of actinometric devices are tapes or films embedded with a substance that changes color in response to radiation. Although these devices can pass through nips, they must be manually placed on the web to expose them to radiation, and manually removed to obtain a reading. They are not continuous measures of radiation in a process.
Another method was developed which monitored the energy draw of the power supply for each lamp, in an attempt to provide a "real time" measurement of the actual energy used by the lamp. This measurement was a very rough and inaccurate way to estimate the amount of radiant energy emitted by the lamp and impinging on the web on a continuous basis. Although inaccurate, this method was an attempt to determine how much radiant energy was impinging onto the web in "real time". Measuring the radiant energy in "real time" made it possible to more accurately control the curing time of the web (e.g., by changing the pace of the web through the process to provide longer or shorter processing time) and reduce loss of product. Unfortunately, many factors made the measurement of the energy drawn from the lamp an inaccurate measurement of the radiant energy impinging the web defeating any advantages gained by the real time measurements. For example, as the lamps themselves degraded due to aging, the amount of energy drawn by the lamp could change relative to the amount of radiation emitted. Additionally, the radiation emitted for a specific amount of power drawn varied from lamp to lamp. To alleviate these problems, electronic detection devices were placed around the lamp to measure the direct output of radiant energy emitted from the lamp. However, the environmental conditions surrounding the process (e.g., high humidity, high temperature, RF radiation, and foreign objects such as airborne adhesive, lacquer, etc.) often caused the electronics in the detectors to break down and malfunction.
Finally, remote collection devices have been developed which allow the radiant energy emitted by the lamp to be collected and transported (typically by fiber optic cables) to a detection device placed remotely from the hostile environment surrounding the web. These devices were placed on the backside of the lamp (opposite the web), allowing a direct measurement of the amount of radiant energy emitted by the lamp to be taken. This placement of these devices on the opposite side of the lamp from the web was done for two main reasons: first, there was very little space between the web and the lamp and second, because the most hostile environment in the process is directly between the web stream and the surface of the lamp housing. The space between the web and the lamp was small in order to keep contaminants such as oxygen (which can affect curing of the web in some processes) to a minimum, as well as assuring that a maximum amount of radiant energy from the lamps impinged the web. The environment is extremely hostile at this position since it is most directly in contact with the radiation and heat from the lamp as well as the adhesive and airborne contaminants from the web.
While remote collection devices solved some of the problems described above, they still did not deliver accurate measurements of radiant energy intensity impinging the web. Typically, a transparent cover is placed over the lamp in order to protect the lamp elements from airborne contaminants. This transparent cover becomes clouded over time (due to airborne contaminants), which prevents a portion of the radiant energy emitted by the lamp from impinging upon the web. Thus, collection devices placed at the back of the lamp do not see this degradation, and an accurate measurement of energy radiated onto the web cannot be attained. None of the devices allowed for the real time collection of radiant energy at the web.


Disclosed are methods of preparing monoalkyl Group VA metal dihalide compounds in high yield and high purity by the reaction of a Group VA metal trihalide with an organo lithium reagent or a compound of the formula RnM1X3−n, where R is an alkyl, M1 is a Group IIIA metal, X is a halogen and n is an integer fro 1 to 3. Such monoalkyl Group VA metal dihalide compounds are substantially free of oxygenated impurities, ethereal solvents and metallic impurities. Monoalkyl Group VA metal dihydride compounds can be easily produced in high yield and high purity by reducing such monoalkyl Group VA metal dihalide compounds.

The present invention relates generally to the field of organometallic compounds. In particular, the present invention relates to monoalkyl Group VA metal compounds which are suitable for use as intermediates in the preparation of precursors for chemical vapor deposition.
Metal films may be deposited on surfaces, such as non-conductive surfaces, by a variety of means such as chemical vapor deposition ("CVD"), physical vapor deposition ("PVD"), and other epitaxial techniques such as liquid phase epitaxy ("LPE"), molecular beam epitaxy ("MBE"), and chemical beam epitaxy ("CBE"). Chemical vapor deposition processes, such as metalorganic chemical vapor deposition ("MOCVD"), deposit a metal layer by decomposing organometallic precursor compounds at elevated temperatures, i.e. above room temperature, either at atmospheric pressure or at reduced pressures.
A wide variety of metals may be deposited using such CVD or MOCVD processes. See, for example, Stringfellow, Organometallic Vapor Phase Epitaxy: Theory and Practice, Academic Press, 2nd Edition, 1999, for an overview of such processes. Organometallic compounds of arsenic, antimony, and bismuth are used to deposit epitaxial films in the semiconductor and related electronic industries. Epitaxial films such as gallium arsenide find applications in optoelectronic devices such as detectors, solar cells, light-emitting diodes ("LED's"), lasers and electronic switching devices such as field effect transistors ("FET's") and high electron mobility FET's ("HEMT's"). Ternary arsenic alloys also exist such as gallium indium arsenide ("GaInAs") and aluminum indium arsenide ("AlInAs"), which are more attractive than GaAs or aluminum gallium arsenide ("AlGaAs") for the most powerful fiber optic systems operating in the 1.3 to 1.55 micron wavelength range. Gallium arsenide phosphide ("GaAsP") is suitable for visible LED's and fiber optic emitters/detectors. Antimony and antimony alloy films are useful in fiber optics communication systems, particularly in the 1.3 and 1.55-micron regions. Antimony-containing semiconductor materials also have commercial applications including detection for seeker, night vision and surveillance devices (infrared detectors) and sources (LED's or lasers). A variety of binary, ternary and quaternary Group III/V semiconductor systems containing antimony have been evaluated for applications in infrared emitters and detectors operating in the 3 to 5 micron and 8 to 12 micron spectral ranges. These wavelength ranges are important since they are natural windows in the atmosphere for infrared transmission. Epitaxial antimony-based Group III/V semiconductors have potential applications in long wavelength detectors and high-speed electronic devices.
Arsine ("AsH3") and phosphine ("PH3") are attractive precursors for MOVPE since they provide arsenic and phosphorus along with hydrogen radicals that can scavenge any carbon-containing radicals generated during the MOVPE growth. However, the highly toxic nature of arsine and phosphine makes handling these gases in cylinders at high pressures dangerous. The threat of their rapid release in large quantities is serious and significantly high facility costs are often incurred to meet the appropriate safety requirements. Thus, there is a need to develop alternative Group VA hydride precursor compounds that are less hazardous than arsine and phosphine. Certain trialkyl Group VA metal compounds, such as trialkyl stibines, have been developed. However, such trialkyl compounds typically have low vapor pressures and higher decomposition temperatures. Such trialkyl compounds also result in carbon incorporation in the grown films. Monoalkyl Group VA dihydride compounds are excellent alternatives as they greatly reduce the amount of carbon incorporated in grown metal films.
For semiconductor and electronic device applications, these Group VA metal alkyls must be highly pure and be substantially free of detectable levels of both metallic impurities, such as silicon and zinc, as well as oxygenated impurities. Oxygenated impurities are typically present from the solvents used to prepare such organometallic compounds, and are also present from other adventitious sources of moisture or oxygen.
One method of preparing monoalkyl arsines and phosphines reacts arsine or phosphine gas with an alkene in the presence of a catalyst. See, for example, European Patent No. EP 579 248 B1 and European Patent Application No EP 560 029 A1. Another method reacts arsine with metallic sodium in liquid ammonia followed by reaction with an alkyl halide. See Magihara et al., Handbook of Organometallic Compounds, W. A. Benjamin, Inc., New York, 1968, pp 560, 566, 571, 574, and 579-580. Both of these approaches require the handling of arsine or phosphine, which are both very toxic.
Grignard type syntheses are also known. For example, arsenic trihalide or a phosphorus trihalide is reacted with an alkyl Grignard reagent to form monoalkyl arsenic or phosphorus dihalides which are subsequently reduced to form monoalkyl arsine or phosphine. See, for example, Japanese Patent Application No. JP 10-130 288. Such reactions are carried out in ethereal solvents. Other preparation methods utilizing ethereal solvents are known. See, for example, Japanese Patent Application No. JP 07-285977. The monoalkyl arsines and phosphines produced by these methods require extensive purification in order to remove the ethereal solvent. Even with such purification procedures, trace ethereal solvents remain in the monoalkyl arsines and phosphines.
Aluminum alkyls can have been used as reagents in the preparation of Group VA metal trialkyl compounds. For example, Zakharkin et al., Bull. Acad. Sci. USSR, 1959, p1853, discloses a method of producing trialkyl compounds of antimony and bismuth, as shown in equation (I), where R is ethyl, n-propyl or iso-butyl and X is chloride or fluoride.MX3+R3Al+diethylether→MR3+AlX3   (I)
Trace amounts of ethereal solvent invariably remain in the target organometallic compound obtained using conventional techniques. Such residual ethereal solvent contributes oxygen as a deleterious impurity in metal films deposited from such precursor compounds.
Attempts have been made to synthesize trialkyl Group VA organometallics in non-ethereal solvents. For example, Takashi et al., J. Organometal. Chem., 8, pp 209-223, 1967, disclose the reaction of antimony trichloride with triethylaluminum in hexane. Such reaction was found to produce triethylstibine in extremely low yields (only about 10%), the remainder being about 42% metallic antimony and about 46% of an antimony-aluminum complex, (SbEt4)(Al2Et5Cl2). This article does not teach how to obtain triethylstibines free of antimony-aluminum complexes.
These trialkyl aluminum reaction approaches have been attempted only in the preparation of certain Group VA metal trialkyl compounds. Such approach has not been disclosed in the preparation of Group VA metal monoalkyl compounds.
Accordingly, there is a need for methods for preparing Group VA metal monoalkyls in high yields and for Group VA metal compounds substantially free of both metallic and oxygenated impurities for use as precursor compounds for CVD.


The present invention relates to a percutaneous-point determination device for determining a location of a point associated with a surface of an animal organ. The device comprises an ultrasound device configured to emit a focused ultrasound beam along an ultrasound beam axis having a known orientation with respect to the ultrasound device. The ultrasound device is configured to output ultrasound data indicative of a distance from the ultrasound device to the point. A position measurement device is configured to output position data indicative of a location of the ultrasound device. The device includes a computer configured to process the ultrasound data and position data to thereby determine a location of the point.

The present invention relates to a device and method for percutaneous determination of locations associated with a surface of an organ.
Medical imaging is used extensively in orthopaedics to view the state of musculo-skeletal structures that require correction, repair or replacement. Planar X-ray, X-ray computed tomography (CT) and magnetic resonance imaging (MRI) are image modalities used preoperatively to diagnose and plan surgical interventions. Transfer of image data to the surgical theater, however, is still mainly intuitive. Computer assisted surgery (CAS), image guided surgery and medical robotics provide a quantitative link between medical imaging using images acquired preoperatively or intraoperatively and surgical actions allowing the surgeon to view, in real time, the orientation of the surgical instruments relative to the patient. This provides the surgeon with a means to precisely navigate and plan tool movements with respect to normally hidden anatomical structures.
A key issue in computer assisted surgery (CAS) is to establish a relationship between the patient""s intraoperative position within an on-site coordinate system and the data of the medical images. The process of computing a transformation from coordinates within an on-site coordinate system to image coordinates is referred to as xe2x80x9cregistrationxe2x80x9d or xe2x80x9cmatchingxe2x80x9d. In the new field of computer assisted surgery (CAS), light-weight xe2x80x9cdynamic reference basesxe2x80x9d allow the surgeon to freely manipulate the patient during complex procedures without losing valuable image generated data. Registration or matching implies obtaining coordinates of points in the medical image reference frame and in the on-site three-dimensional coordinate system in space from the position measurement device.
Current registration processes are invasive requiring the surgeon to have direct access to fiducial markers implanted in the bone or specific, predetermined landmarks on bone surfaces that are digitized with a positioning device. Recent developments allow the surgeon to obtain a number of points of the bone with the positioning device and this xe2x80x9ccloud of pointsxe2x80x9d can be mathematically fit onto the medical image (e.g. Computer tomogram CT) of the bone surface through an optimization algorithm. This process is termed xe2x80x9csurface matching.xe2x80x9d Although these invasive registration processes have greatly improved the versatility of CAS systems, they require large incisions or transcutaneous needles that pierce the skin and touch the surface of the bone. Because orthopaedic surgery often involves bones hidden deep beneath soft tissues, open procedures can expose the patient to both significant risks of infection and long recovery times.
U.S. Pat. No. 5,447,154 to Cinquin, et al. discloses a method for determining the position of an organ and for positioning a therapeutic or diagnostic tool as a function of three-dimensional images. The images can be preoperative images, such as X-ray computed tomography (CT) images or Magnetic Resonance Images (MRI) of a patient""s organ. A device provides a sparse set of three-dimensional surface points on the organ of interest during surgery. These surface points are registered (matched) with the three-dimensional functional image, which contains far more detailed information on the organ""s surface morphology. Echography probes are used to intra-operatively obtain the sparse set of three-dimensional surface points of the organ. The organ surface is obtained by analyzing a reconstructed two-dimensional xe2x80x9cimage slicexe2x80x9d provided by the ultrasound probe. Both the ultrasound probe and the organ are instrumented with a three-dimensional position tracking device which allows calculation of the identified surface point in 3D space with respect to the patient.
A device for recording ultrasound images is disclosed by W098/08112 to Emmenegger et al. The position of each ultrasound image is uniquely defined with respect to any arbitrary three-dimensional coordinate system in space through determination of the position and orientation of the ultrasound head. The device comprises an ultrasound head, which can be freely moved by hand, an ultrasound recording apparatus and a three-dimensional position measurement system to determine the position of the ultrasound head. The position of the ultrasound head is determined by measuring lengths of at least three points affixed to the ultrasound head. The length measurements are realized via interchanging electromagnetic energy between markers attached to the ultrasound head and sensors that are part of the position measurement system.
A disadvantage of known methods and devices is the use of reconstructed ultrasound images to intra-operatively identify points on the organ""s surface. Identifying points associated with an organ surface from a noisy ultrasound-generated image is difficult. Much information on exact anatomy contour is lost in image reconstruction and conversion to a video signal and digitization of this signal. Because ultrasound systems are generally designed to image soft tissues, they are sensitive to small changes in acoustic impedances. This produces a considerable amount of xe2x80x9cnoisexe2x80x9d in the constructed image and obscures the surface of the bone. Using the video output of these systems further degrades the signal. The picture must then be manually segmented (i.e. finding the surface of the bone), which requires operator input. Once the picture has been segmented, the surface points can be automatically fitted to the coordinate system of the preoperatively acquired CT image. A practical minimally invasive registration would greatly expand the usefulness of CAS technology.
One embodiment of the present invention relates to a percutaneous-point determination device for percutaneous determination of coordinates of points associated with the surface of an organ of an animal, such as a human. The organ is preferably a bone. Locations of the points are preferably determined within an on-site coordinate system by processing data obtained from a reflection of a focused one-dimensional ultrasound beam from the organ. The associated points are preferably located at or on the surface of the organ, such as a landmark of a bone.
The device can be used to, for example, determine specific anatomical landmarks, such as the spinous process, and left and right superior facet joints, to be used for paired point matching. The device can also be used to determine a cloud of points associated with the organ surface to be used for surface matching a medical image to the organ.
The device includes a processor to process ultrasound data received from the ultrasound device to thereby provide accurate information on anatomical surface location. The ultrasound data are preferably a raw signal. The processing may be performed in real-time.
The ultrasound beam preferably has a sufficiently narrow width to minimize detection of dispersed signals. The coordinates of points can be determined with at least about 0.5 mm axial accuracy and location of the point in the 3-D coordinate system can be determined with an accuracy of less than about 1 mm.
In a preferred embodiment, the percutaneous-point determination device includes an ultrasound device configured to emit an ultrasound beam along an ultrasound beam axis. The ultrasound beam is preferably focused. The ultrasound beam axis preferably has a known orientation, such as a known orientation with respect to the ultrasound device.
The ultrasound device includes at least three preferably non-collinear markers. The markers can include energy emitting, receiving, or reflecting elements. Energy emitting elements include light emitting elements such as, for example, light emitting diodes (LED""s) and infrared light emitting diodes (IRED""s). Alternative energy emitting elements include, for example, acoustic transmitters and coils configured to establish a magnetic field.
Energy receiving elements include light sensitive elements, such as, for example, photodiodes. Other suitable energy receiving elements include, for example, microphones or Hall-effect elements.
A position measurement device is configured to determine the position of the markers with respect to a three-dimensional reference coordinate system, which may be an on-site coordinate system. The device includes a computer in communication with the ultrasound device and position measurement device. The computer is configured, such as by software, to process ultrasound data received from the ultrasound device and position data received from the position measurement device to thereby determine the location of the point. The ultrasound device is preferably an integral element of a computer assisted surgery system (CAS).
The ultrasound device also comprises a transducer to emit and receive, preferably alternately, acoustic energy such as ultrasonic waves, preferably in the form of an ultrasonic beam. A pulser is configured to cause the transducer to emit the acoustic energy. A receiver receives and preferably amplifies the echo of the ultrasound signal emitted by the transducer. The ultrasound device receiving the echo of the ultrasound signal is configured to output ultrasound data indicative of a distance from the ultrasound device to the point. The pulser and receiver are preferably combined and under computer control. A converter converts the analog signal received from the combined pulser/receiver unit into a digital signal.
The ultrasound device preferably emits the ultrasound beam along an ultrasound beam axis. The one-dimensional acoustic signals can be processed with minimal signal processing thereby increasing measurement speed. A point to be located within the coordinates of a three-dimensional coordinate system is defined by the point of intersection of the ultrasound beam axis and the surface of the organ. Because the location, i.e., position and orientation, of the ultrasound device can be determined by the position measuring device, the location of the point within the coordinate system of the ultrasound probe can be determined using the received acoustic signals. The computer is configured to convert the coordinates of the point from the coordinate system of the ultrasound device into coordinates within the on-site coordinate system, such as relative to the organ or other reference base. Thus, the computer processes the ultrasound data and position data to thereby determine the location of a point associated with the surface of the organ.
In another embodiment, the device is provided with a high-speed analog to digital converter board (ADC), a fast processor and signal analysis software in order to obtain real-time data processing. The transducer is preferably configured to emit acoustic energy having a predetermined frequency f, thereby enabling a desired axial resolution of the ultrasound beam at a particular penetration depth of the emitted acoustic energy. The axial resolution is the minimal distance along the ultrasound beam axis that two distinct echoes can be distinguished from one another. It is dependant on the wavelength xcex of the ultrasound beam wherein the wavelength xcex is related to the frequency f by xcex=c/f wherein c is the average velocity of sound. For example, suitable results for obtaining points on a bone surface are achieved using a frequency f of the transducer within the range of 1 MHZ to 15 MHZ, preferably within the range of 4 MHZ to 6 MHZ.
Higher frequencies f provide better resolution but are attenuated faster in tissue than lower frequencies f. As a result, the mean frequency penetrating the tissue becomes lower as it travels deeper into the tissue. Thus, the highest frequency that will penetrate to a given depth is chosen to yield the best axial resolution.
The lateral resolution varies along the depth of the signal but is preferably less than 1 mm at the xe2x88x929 dB point. The ultrasound beam can be focused within the near field region given by: N=D2*f/4c, wherein D is the diameter of the transducer and N is the length of the near field. With higher frequencies and the larger diameter transducers, the beam can be focused more tightly, yielding better lateral resolution.
The diameter of the transducer depends on the application. For example, a smaller diameter is suitable for shallower depths. In one embodiment, the transducer has a diameter of about 12.7 mm. The ultrasound device is preferably provided with lenses such that the ultrasound beam is focusable in order to increase signal quality and accuracy. The device preferably includes a at least one lens to allow the ultrasound beam to be focussed to a lateral resolution of less than about 1 mm over a depth range of from about 1 mm to 80 mm. In the preferred embodiment, two detachable flat surface axicon lenses are used for focusing the ultrasound beam to depths of 5-30 mm and 25-75 mm, respectively, with a lateral resolution of 1 mm at xe2x88x929 dB. The lenses attached to the ultrasound device, such as with a screw cap, and are designed to have an optimal interface with the skin, i.e., allowing maximum energy to be transferred to the tissue.
In another embodiment, the device comprises a calibration unit to calibrate the ultrasound head. The calibration unit is configured to receive the ultrasound head in a known position and orientation with respect to a reference portion of the calibration unit. The calibration unit allows the calibration of a coordinate system of markers associated with the ultrasound device with respect to the on-site coordinate system to thereby allow the percutaneous determination of the three dimensional position of the point associated with the surface of the organ from which the ultrasound signal is echoed.
The calibration unit preferably includes markers to allow the position and orientation of the calibration unit to be determined by the position measurement device. Therefore, the position measurement device can determine relative positions and orientations of the ultrasound head and calibration unit. Echoes received from the reference portion can be used to calibrate, for example, an offset between the ultrasound head and the reference portion.
The calibration unit is preferably formed of a material in which the sound velocity is known. A suitable material is plastic, for example, a thermoplastic, such as PLEXIGLASS. The calibration unit includes a receiving location, such as a hole having a diameter to receiver the ultrasound device. For example, the calibration unit may be rectangular or cube shaped with the hole drilled in the center such that the distance from the bottom of the hole to the bottom of the calibration unit is in the range of between about 20 mm to 30 mm. During calibration, the ultrasound device is received by the receiving location. Echoes are received from the interface of the bottom of the calibration unit and the surrounding medium, which is preferably air. These echoes are large and easy to detect. Because the speed of sound within the calibration unit and the distance traveled are known, the echo can be used to calculate an offset from the ultrasound device head to the interface.
The offset is preferably used in subsequent determinations of point locations. For example, echos received during calibration are preferably used to determinate a signal template, i.e., instrument response of the ultrasound pulser/receiver. The signal template is reference ultrasound data that can be used in the determination of the distance from the ultrasound device to the organ. For example, during use, point location determination preferably comprises obtaining the cross-correlation of the signal template with received echos. For example, the location of a bone tissue interface can be determined by cross-correlation of the received echo and the signal template. As alternatives to cross-correlation algorithms, a standard deviation algorithm (STDDEV) or a short time Fourier transform algorithim (STFT) can be used.
In another embodiment of the device according to the invention, a 10 MHZ ultrasound device includes a delay line to allow focusing between 1 mm and 10 mm. The transducer is electrically driven and the electrical signal caused by the echo is received by a pulser/receiver, which is controlled by the computer. The pulser/receiver unit is capable of initiating a pulse having an energy between 80 xcexcJ and 120 xcexcJ, preferably between 95 xcexcJ and 105 xcexcJ and has a maximum gain of approximately 50 dB. The pulser/receiver sends a high voltage pulse with a voltage of between 200 V-400 V to excite the transducer. This pulse is sharp, having a width of less than the inverse of the resonance frequency of the transducer. The receiver amplifies and filters the signal received from the transducer.
A preferred embodiment of the invention operates with a CAS application running on a workstation in a client-server architecture. A computer is configured as an ultrasound server and position data of points associated with the organ are transmitted to the client application through a UDP socket connection to the workstation running position measurement software whenever a request is made. The computer employs a client-server architecture including the computer controlling the ultrasound device and a workstation running position measurement software and CAS application. In another embodiment the device includes a single computer comprising hardware and software configured to operate the ultrasound device, the position measurement device and, preferably, a CAS application.
Another embodiment of the invention relates to a method for the percutaneous determination of coordinates of points associated with the surface of an organ of an animal, such as a human. The organ is preferably a bone. The coordinates are preferably determined within a three-dimensional coordinate system.
The method preferably comprises calibrating the ultrasound head and emitted ultrasound beam axis with respect to a coordinate system fixed with the ultrasound device in order to calculate echo distances. The coordinate system fixed with the ultrasound device is calibrated with respect to the on-site coordinate system in order to determine the three dimensional position of the point on the surface of the organ reflecting the ultrasound signal. The coordinates of points on the surface of the organ are determined with respect to a three-dimensional coordinate system by real-time by raw signal processing.
Yet another embodiment of the invention relates to a device for the percutaneous obtainment of coordinates of points on the surface of a human or other animal organ within a three-dimensional coordinate system. The device comprises an ultrasound device having an axis coinciding with an emitted ultrasound beam axis. The ultrasound device includes at least three energy emitting, receiving or reflecting means serving as markers. A position measurement device is configured to determine the position of the markers with respect to a three-dimensional reference coordinate system in space. At least one computer is operably connected to the ultrasound device and the position measurement device. The computer preferably allows real-time determination of coordinates associated with the surface of the organ, which is preferably a bone. The ultrasound device includes focusing means to focus the ultrasound beam, which is preferably highly focusable to thereby increase signal quality and accuracy.
The focusing means are preferably lenses, such as detachable fluid filled lenses or detachable flat lenses. The ultrasound beam is preferably focusable to 1 mm lateral resolution over a range from 1 mm to 80 mm depth. The ultrasound device preferably emits ultrasound having a predetermined frequency to thereby provide a desired axial resolution of the ultrasound beam at a predetermined depth of penetration of the emitted ultrasound. The frequency of the ultrasound is preferably within the range of 1 MHZ to 15 MHZ.

Method and device for percutaneous determination of points associated with the surface of an organ