In an area to be monitored, first signaling information is deliberately emitted to synthetically create conditions which force the mobile radio terminals that are to be detected to transmit second signaling information as a reaction. The second signaling information is then processed in order to detect mobile radio terminals which are not switched off.

The invention relates to a method for protection of a limited local area against electromagnetic radiation, in particular the electromagnetic radiation that occurs when a mobile radio terminal is transmitting. The invention further relates to a radio station and to a mobile radio terminal.
Modern cellular mobile radio systems, such as the popular GSM system, are comprised of a large number of mobile switching centers that are networked to one another and produce access to a fixed network PSTN. Furthermore, the mobile switching centers are each connected to at least one base station controller. Each base station controller is in turn connected to at least one base station (base transmitting/receiving station). Such a base station is a radio station which can set up a radio link to other radio stations, so-called mobile stations (mobile radio terminals) via a radio interface.
For the purposes of this application, the term radio station also covers a base station, a (mobile radio) transmitting/ receiving device, a base transmitting/receiving station, and a radio station which at least partially operates on the principle of a base transmitting/receiving station for one or more mobile radio systems and has appropriate transmitting, receiving and processing devices.
The physical transmission resources for the radio path are assigned to logic mobile radio channels in accordance with a defined scheme and using a multiple access method such as a TDMA, FDMA, or a CDMA method. In principle, there are two types of logic mobile radio channel: signaling channels for transmitting signaling information, and traffic channels for transmitting wanted data, i.e. useful data. The logic mobile radio channels may be assigned to a specific link between a base station and a mobile station. Data can be transmitted between the mobile stations and the base station associated with these mobile stations by means of radio-frequency electromagnetic waves.
In many cases, this may be undesirable, particularly if these electromagnetic waves can interfere with other sensitive electronic equipment. For example, it is possible for the complex electronics in modern aircraft to be interfered with by the use of mobile telephones by passengers flying in the aircraft, which may lead to difficulties in controlling the aircraft. Some airlines and regulatory agencies therefore ban the use of mobile telephones. Currently, passengers are made aware of these dangers by a corresponding announcement and they are requested not to use their mobile telephones. In most cases the mobile telephones are then switched off manually by the mobile-telephone users. This prior art procedure is very complex and, naturally, quite unreliable.
It is accordingly an object of the invention to provide a method of protecting a limited local area against electro-magnetic radiation emitted by mobile radio terminals, a corresponding radio station and a mobile radio terminal, which overcome the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and which allows a limited local area to be protected against electromagnetic radiation in a simple, efficient and reliable manner.
With the foregoing and other objects in view there is provided, in accordance with the invention, a method of protecting a limited local area against electro-magnetic radiation emitted by mobile radio terminals, which comprises:
emitting signaling information with a transmitting device about a location area associated with the transmitting device;
causing, upon a reception and processing in a mobile radio terminal, an emission of second signaling information for updating the location area of the mobile radio terminal;
receiving the second signaling information with a receiving device; and
processing the second signaling information for detecting mobile radio terminals that are not switched off.
The invention is accordingly based on the idea of deliberately emitting signaling information in the area to be monitored in order to synthetically create conditions which force the mobile radio terminals to be detected to transmit signaling information, and processing of this signaling information leads to detection of mobile radio terminals which are not switched off.
If a radio station transmits signaling information over the location area associated with the radio station, whose reception and processing in a mobile radio terminal forces signaling information to be emitted in order to update the location area, then it is possible for mobile radio terminals which are not switched off to be actively required to emit signaling information by means of which they can easily be detected. Already known signaling procedures can be used for this purpose.
The invention makes it possible, simply and reliably, to identify whether or not there are any mobile radio terminals that are not switched off in an area to be monitored, and allows appropriate measures to be taken to protect a limited local area against electromagnetic radiation.
Mobile radio terminals also exist which interchange information with the mobile radio system at specific time intervals even in the standby mode. For the purposes of this application, switching off thus also means that the mobile radio terminal is switched to a state in which it can no longer emit any signals which could lead to significant interference with other electronic equipment.
In accordance with an added feature of the invention, the processing step comprises displaying information about the mobile radio terminals that are not switched off.
In accordance with an additional feature of the invention, the emitting step comprises emitting with the transmitting device a plurality of different signaling information items corresponding to different mobile radio systems, and the receiving step comprises receiving with the receiving device a plurality of different signaling information items corresponding to different mobile radio systems.
In other words, the radio station is operated at least partially on the principle of a base transmitting/receiving station for different mobile radio systems.
This means that the invention may be used in different countries, and mobile radio terminals of all persons and of the corresponding different mobile radio systems can be detected in monitoring areas which are generally entered by an international population (airports).
In accordance with another feature of the invention, the transmitting device transmits, after a fixed or variable time interval, signaling information about a changed location area associated with the transmitting device.
It is thus possible even for a mobile radio terminal which has already been detected and is switched on again after having first been switched off to emit signaling information relating to the change in the location area.
In accordance with a further feature of the invention, the transmitting device and/or the receiving device is/are not connected to switching centers.
Advantageously, the radio station operates at least partially on the principle of a base transmitting/receiving station of a mobile radio system that is not to be connected to switching centers. This means that the radio station can be designed to be technically very simple, cheap, and even to be portable.
In accordance with again an added feature of the invention, the transmitting device and the receiving device are integrated in a base transmitting/receiving station which at least partially operates on a principle of different mobile radio systems.
In accordance with again an additional feature of the invention, the signaling information emitted by the transmitting device is received only with those mobile radio terminals that have a specific physical relationship with the transmitting device.
This has the advantage that the only mobile radio terminals which are detected are those located in the area monitored by the invention.
In accordance with again another feature of the invention, the method further comprises:
causing with the processing of the second signaling information an emission of third signaling information via a radio interface using the principle of a mobile radio channel;
receiving the third signaling information with a mobile radio terminal; and
processing the third signaling information with programmable processor devices, and deactivating at least one transmission function of the mobile radio terminal.
In accordance with again a further feature of the invention, signaling information is transmitted for deactivating a transmission function after a first signaling phase of setting up a connection.
In accordance with yet again a further feature of the invention, the mobile radio terminal is placed into a state in which at least one transmission function is deactivated, and it can no longer be activated as long as the mobile radio terminal is in the state.
With the above and other objects in view there is also provided, in accordance with the invention, a radio station, comprising:
a transmitting device for transmitting signaling information over a location area, wherein the signaling information is not emitted at the same time by an adjacent base transmitting/ receiving station, and wherein a reception and processing of the signaling information in a mobile radio terminal leads to the emission of second signaling information;
a receiving device for receiving the second signaling information transmitted by the mobile radio terminals for updating the location area;
a processing device connected to the receiving device for processing the second signaling information; and
a display device connected to the processing device for displaying information about mobile radio terminals in the location area that are not switched off.
In accordance with yet an added feature of the invention, the transmitting device is adapted to emit, after a fixed or variable time interval, changing signaling information over a location area.
In accordance with yet an additional feature of the invention, the radio station is not connected to a switching center.
In accordance with yet another feature of the invention, the transmitting device, the receiving device, and the processing device are designed to process signaling information for different mobile radio systems.
With the above and other objects in view there is also provided, in accordance with a concomitant feature of the invention, a mobile radio terminal, comprising:
a receiving device for receiving signaling information;
programmable processor devices connected to the receiving device for processing the signaling information; and
means for deactivating at least one transmission function of the mobile radio terminal as a function of the received and processed signaling information.
In another, above-mentioned refinement of the invention, signaling information is emitted by a radio station via a radio interface, which signaling information is received and processed by a mobile radio terminal, and this process leads to deactivation of a transmission function of the mobile radio terminal.
This means that the handling of mobile radio terminals is limited automatically, reliably and efficiently to those functions which cause no interference with the environment. It is no longer required that the apparatus is manual switched off.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a method for protection of a limited local area against electromagnetic radiation emitted by mobile radio terminals, a radio station and a mobile radio terminal, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

Method of protecting a limited local area against electromagnetic radiation emitted by mobile radio terminals, radio station and mobile radio terminal


A Li-ion polymer battery and methods for its fabrication. A first and second layer, of a polymer/particulate material composition, separate and bind each anode and cathode. The polymer of the first layer and its associated solvent differ from the polymer of the second layer and its associated solvent. Solubility requirements are such that the polymer of the first layer is non-soluble in the solvent of the second layer, and the polymer of the second layer is non-soluble in the solvent of the first layer. The polymers and particulate materials of the layers form a porous structure for containing the electrolyte of the battery so as to eliminate the need for a substantial case for enclosing the battery.

Lithium-ion polymer batteries are fabricated by various methods. In U.S. Pat. No. 5,536,278 an electrolyte film, previously prepared, is heated and laminated to a first electrode. The second electrode is then laminated to the laminated first electrode.
In U.S. Pat. No. 5,778,515 an electrode film and a separator film are formed then laminated after use of a pre-lamination solvent on the surface at least one of the films.
In U.S. Pat. No. 6,024,773 a separator film is coated on both sides with a binder resin solution so as to bond the electrodes with the separator film separating them.
In U.S. Pat. No. 5,348,824 polymer based amorphous compositions are melt extruded in the form of a thin film directly on the positive electrode of a lithium battery.
In all of the processes in which a sheet or film is formed, the composition of the separator material is limited to polymers having satisfactory mechanical strength for forming a thin film and for carrying out the laminating process with the electrodes. Use of particulate material in the polymer, to any great extent, is nearly impossible with any polymer as the mechanical strength is decreased further with the addition of the particulate material. In melt extended polymers, the porosity is difficult to control and is typically low.
Those disadvantages and other are overcome with use of the present invention.

Structure and methods of fabricating binding layers for a Li-ion polymer battery


The present disclosure relates to lignocellulosic biomass processing and refining to produce hemicellulose and cellulose sugars. Methods and systems for refining a lignocellulosic hydrolysate are provided herein.

Lignocellulosic biomass materials are renewable sources for production of amino acids for feed and food supplements, monomers and polymers for the plastic industry, and renewable sources for different types of fuels, polyol sugar substitutes (xylitol, sorbitol, manitols and the likes), and numerous other chemicals that can be synthesized from C5 and C6 sugars. Nonetheless, efficient and cost effective processes to extract C5 and C6 sugars from the biomass are still a challenge.
Classical sugar refining from corn milling comprises a sequence of resin-based ion exchangers to remove cations, anions, non-ionic compounds and color bodies. This technology has been well developed for starch hydrolysates since the 1960's and 70's and is still the method of production of sugars from corn and other easy to hydrolyze feedstocks.
It is well known that methods applied for producing 1st generation sugars, i.e., from starch or sucrose feedstocks, are too costly when applied to 2nd generation sugar production, i.e., from biomass. Biomass hydrolysis requires more severe conditions to effectively hydrolyze it as compared to starch. For example, stronger and/or more concentrated acids are used, and temperature and/or pressure of reactions are increased, all resulting in greater formation of degradation products that must be removed. Much of the increased cost is due in part to the impact of organic acids, which are an inherent component in biomass hydrolysates on the WBA resin.
The anions of biomass associated organic acids can be adsorbed by the WBA, but their adsorption is accompanied by a striking swelling of the resin, ten-fold greater than the swelling caused by mineral acid. Inherently, the resin holds a finite number of adsorption sites (e.g., the number of ammonium groups in a given volume of resin is finite), and once exhausted the resin is regenerated by: (i) washing the resin with water to recover sugar from the resin volume, yielding a "sweet water" having 2-4% sugars; (ii) periodic regeneration with mineral acid to remove the organic acid; (iii) regeneration with caustic or soda ash to prepare the resin for the next cycle; and (iv) a final wash to remove excess base. Consequently, when regenerating the resin with base, the resin shrinks. In the next adsorption cycle the resin swells again. The result of these swelling and shrinking cycles mechanically grinds the resin to dust, leading to poor mass transfer in washing, production and regeneration functions and eventually frequent need to replace the resin at high cost. When applied to refining of bagasse hemicellulose hydrolysate, the lifetime of a WBA resin is about half of that for the typical operation of refining corn sugars. Other feedstocks that release higher amounts of acetic acid in hydrolysis, such as eucalyptus, shorten the lifetime of the resin even more.

Methods of refining a lignocellulosic hydrolysate


A method and apparatus for cleaning and recycling stack gas from coal-fired power plants, from natural or propane burning heating plants, or from cement kilns by using renewable catalysts of zeolite to separate pollutants into recyclable and reusable materials. The method reduces from the stack gas carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxide (NOx), sulfur oxide (SOx) as well as halogens such as chloride and fluorides and trace metals particularly, mercury, lead, and zinc.

This invention relates to cleaning of stack gases such as those from coal fired power plants, from natural or propane burning heating plants, or from cement kilns. The stack gases exhausted from such facilities are controlled by environmental regulations. Such regulations require abatement of carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxide (NOx), sulfur oxide (SOx) as well as halogens (such as chloride and fluorides) and trace metals, particularly mercury, lead, and zinc.
Various methods and apparatuses have been proposed for abating these pollutants in stack gases. In particular, a variety of methods have been proposed for reducing pollutants released from coal-fired stack gas. One method of cleaning coal-fired stack gas is the use of scrubbers that inject a liquid or slurry into a gas stream that washes various pollutants, such as with acidic compounds, from the stack gas stream. Another type of cleaning is the use of an exhaust burner that combusts volatile materials and other combustible compounds reducing pollution in the stack gas.
Specifically, it has been proposed that the stack gases be mixed with ammonia or urea and then passed through a catalyst in which the ammonia reacts selectively with the nitrous oxides to form nitrogen gas in water vapor, or combustion of a sulfur-containing fossil fuel in the presence of a calcium carbonate or magnesium carbonate to form calcium sulfate or magnesium sulfate. See U.S. Pat. Nos. 8,181,451; 6,706,246; 5,525,317; 5,237,939; 4,185,080; and 4,051,225. It has also been proposed to reduce nitrogen in stack gas by passing the stack gas through a heat exchange having a SCR catalyst. See U.S. Pat. No. 5,918,555. Reduction of sulfur oxide content in stack gases gas been proposed involving catalyzed oxidation to sulfur trioxide in the presence of an absorbent or combusting sulfur-containing fuel in a combustion zone charged with a slurry in sulfuric acid solution. See U.S. Pat. Nos. 5,540,755; 4,649,034; 4,284,015; and 4,185,080. Catalytically converting unburned hydrocarbons and carbon monoxide to carbon dioxide and reducing nitrogen oxides to nitrogen subsequent to the combustion of fossil fuels, while absorbing sulfur oxide has been proposed, where the catalytic material is physically combined onto a dry powder of an adsorbent matrix selected from calcium aluminate, calcium aluminate cement, barium titanate, and calcium titanate. See U.S. Pat. No. 4,483,259. It has also been proposed to pass the stack gases through a catalyst bed of a combination of active metals on the surface that is capable of reducing or converting sulfur oxides, carbon monoxide and hydrocarbons to inert compounds such as carbon dioxide, water and nitrogen. See U.S. Pat. No. 7,399,458. Levels of mercury in stack gases from coal combustion have also been reduced by introducing a sorbent composition into the gas stream in a zone where temperature is greater than 500° C., where the sorbent composition comprises an effective amount of nitrate salt and/or a nitrite salt. See U.S. Pat. Nos. 7,468,170 and 7,731,781.
Other types of cleaning stack gas have also been proposed and will be known to those having skill in the art. These previous proposals have a number of drawbacks. Many require addition of another gas or liquid such as ammonia, sulfuric acid, or the presence of an active metal catalyst.
One particular problem unresolved by current technology is carbon gaseous pollutants that cannot be reduced by scrubbing or combustion. It has been proposed to capture the carbon in the form of carbon dioxide, compress the carbon dioxide, and storing it in a geological formation. Zeolite has been proposed among others materials to absorb carbon dioxide, and after sequestering the carbon dioxide then to be able to regenerate the zeolite material. See "Carbon Dioxide Capture Using a Zeolite Molecular Sieve Sampling System for Isotopic Studies (13C and 14C) of Respiration", Radiocarbon, 47, 441-451 (2005); "Absorbent Materials for Carbon Dioxide Capture from Large Anthropogenic Point Sources", Chem Sus Chem 2009, 2, 796-854; "NIST Provides Octagonal Window of Opportunity for Carbon Capture", NIST Techbeat, Feb. 7, 2012. However, these uses of zeolite generally involved large particle sizes of zeolite; for example, between 1/16 and ⅛ inch in size under conditions to provide for adsorption of carbon dioxide and later regeneration. These methods of absorbing carbon dioxide highlight the continuing problem of disposing of sequestered carbon dioxide.
There is therefore still a need for a method and apparatus to effectively remove carbon monoxide, carbon dioxide, nitrogen oxides, sulfur oxides and trace metals, such as mercury, from stack gases without consuming expensive catalysts, without injecting additional gases, liquids and/or solids into the stack gas, and without creating waste products that themselves present problems and costs in disposal. This is of particular concern in cleaning of stack gases coal from power plants because of the release of volatiles such as coal tar and other active pollutants along with carbon dioxide in the stack gas.
However, an added problem is the water vapor content of the stack gas reaching the cleaning system. The moisture content of typical stack gas exited from a baghouse and directed to a cleaning system is typically 12% to 14% water, or higher, and the difficulty of stack gas cleaning with the available water vapor content causes the catalyst to be swamped and inoperative for commercial applications. The catalyst is inoperative to reduce carbon monoxide, carbon dioxide, nitrogen oxides and sulfur oxides to produce oxygen and residuals. Therefore there is still a need for an effective and commercially viable method of reducing the water vapor content of stack gas before reaching the catalyst so that the catalyst can effectively reduce carbon monoxide, carbon dioxide, nitrous oxides and sulfur oxides to oxygen and residuals.
Presently disclosed is an apparatus for drying and cleaning stack gases comprising: (a) a first catalytic flow-through bed of natural calcium zeolite with a porosity of a total surface area of not greater than 1200 m2/g adapted to reduce carbon oxides present in an exhaust stack; (b) a second catalytic flow-through bed of a blend of natural sodium zeolite and natural calcium zeolite of a porosity with a total surface area of not greater than 1200 m2/g adapted to reduce sulfur oxides present in the exhaust stack downstream of the first bed; (c) a third catalytic flow-through bed of natural calcium zeolite with a porosity of a total surface area not greater than 1200 m2/g adapted to reduce nitrogen oxides present in the exhaust stack downstream of the second bed; (d) a pair of electrodes adapted to be positioned inline in the gas flow upstream of the first catalytic flow-through bed and insulated from containment of the gas flow, such as with a pipe, and applying D.C. voltage between the electrodes to ionize water vapor without creating substantial amounts of hydrogen gas and reduce moisture content of the gas flow through the catalytic flow-through beds; (d) an exhaust stack adapted to provide a gas flow, selected from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln, sequentially past the pair of electrodes and through the first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed, each catalytic bed collecting residuals, and providing stack gases exiting the third catalytic flow-through bed with at least 70% reduction in sulfur oxides, nitrogen oxides, and carbon oxides; and (e) the first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed each adapted to be periodically purged with nitrogen to remove solids and/or liquids collected in the first catalytic flow-through bed, the second catalytic flow-through bed, and/or the third catalytic flow-through bed so each catalytic flow-through bed can be prepared for reuse. Note the first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed may include other zeolites particle sizes as explained in more detail below.
The electrodes may be positioned in the gas flow downstream of a baghouse. The D.C. voltage applied between the electrodes may be less than 34 volts which may be effective to ionize the water vapor as previously described, but be sufficiently low to avoid the presence of hydrogen gas in substantial quantities downstream of the catalytic beds in the stack gas stream, as described. The electrodes in the gas flow upstream of the first catalytic flow-through bed insulated from containment of the gas flow may apply such voltage to ionize water vapor in the gas flow and reduce moisture content of the gas flow in the first catalytic flow-through bed to be below 8% or 5% or a lower or different moisture content as desired.
The exhaust stack may be adapted to exit gases from the third catalytic flow-through bed with at least 80% or 90% reduction in carbon oxides, sulfur oxides, and nitrogen oxides compared to the stack gases after reaching the electrodes.
The apparatus in addition may have a venturi positioned in the gas flow downstream of the third catalytic flow-through bed to stabilize gas flow through the beds. The apparatus may also include stabilizing veins to improve laminar flow of the stack gases through the beds. Stabilizing veins may improve efficiency of separation of pollutants from the stack gases. Stabilizing veins may be positioned upstream or downstream of the electrodes in the gas stream, but may be more advantageously positioned downstream of the electrodes.
The blend of natural sodium zeolite and natural calcium zeolite in the second catalytic flow-through bed may be between 25% and 75%.
The first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed may also each have a porosity of total surface area not greater than 800 m2/g. Also a fourth catalytic flow-through bed of calcium zeolite may also be provided in the gas flow after passing the pair of electrodes and before the first catalytic flow-through bed with a porosity of total surface area not greater than 1200 m2/g, or not greater than 800 m2/g, adapted to collect bauxite compounds before passage through the first catalytic flow-through bed. The fourth catalytic flow-through bed also may be adapted to be periodically purged with nitrogen. Where a fourth catalytic flow-through bed is provided, exhaust stack gases may exit from the third catalytic flow-through bed with at least 70% or 90% reduction in bauxite compounds, carbon oxides, sulfur oxides, nitrogen oxides, and mercury oxides compared to the stack gases delivered through the pair of electrodes.
The apparatus may comprise at least two series of sequential gas flows both through a pair of electrodes, a first catalytic flow-through bed, a second catalytic flow-through bed, and a third catalytic flow-through bed, provided in parallel, so stack gases can be cleaned through one of the series of beds while other series of beds can be purged.
Also disclosed is a method of drying and cleaning stack gases comprising the steps of:                (a) passing a contained stack gas flow, selected from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln, through a pair of electrodes adapted to be positioned inline in the gas flow and applying a D.C. voltage between the electrodes to reduce moisture content of the gas flow through the catalytic flow-through beds without creating substantial amounts of hydrogen gas;        (b) passing stack gas flow from the electrodes through a first catalytic flow-through bed of calcium zeolite comprising natural zeolite particles of a majority between 44 μm and 64 μm in size at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce carbon oxides in the stack gas flow;        (c) passing the stack gas flow from the first catalytic flow-through bed through a second catalytic flow-through bed of a blend between 25% and 75% of sodium zeolite and calcium zeolite comprising natural sodium and calcium zeolite particles of a majority between 65 μm and 125 μm in size at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce sulfur oxides in the stack gas flow;        (d) passing the stack gas flow from the second catalytic flow-through bed through a third catalytic flow-through bed of calcium zeolite comprising natural zeolite particles of a majority between 78 μm and 204 μm at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce nitrogen oxides in the stack gas flow; and        (e) operating the stack gas flow sequentially past the pair of electrodes and through the first catalytic bed, the second catalytic bed, and the third catalytic bed to provide at least 70% reduction in sulfur oxides, nitrogen oxides and carbon oxide in the stack gas flow.
In the method, the voltage between the electrodes may be below 34 volts, and the gas flow sequentially circulated past the pair of electrodes and through the first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed also may remove from the gas flow at least 50% or 70% of mercury in all forms. The pair of electrodes in step (a) may also be positioned in the gas flow downstream of a baghouse. The method of drying and cleaning stack gas may also have the pair of electrodes in the gas flow upstream of the first catalytic flow-through bed insulated from containment of the gas flow with D.C. voltage applied to the electrodes to ionize water vapor in the gas flow and reduce moisture content of the gas flow in the first catalytic flow-through bed, preferably to below 8% or 5%% or a lower or different moisture content as desired.
Alternatively, a method of drying and cleaning stack gases is disclosed comprising the steps of:                (a) passing a contained stack gas flow selected from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln by a pair of electrodes positioned inline in the gas flow and applying a D.C. voltage between the electrodes to ionize water vapor in the gas flow without creating substantial amounts of hydrogen gas and to reduce moisture content of the gas flow in the catalytic flow-through beds to the moisture content in the gas flow before reaching the pair of electrodes;        (b) passing stack gas flow from the pair of electrodes through a first catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles of a majority between 44 μm and 64 μm in size at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce carbon oxides in the stack gases;        (c) passing the stack gas flow from the first catalytic flow-through bed through a second catalytic flow-through bed comprised of a blend between 25 and 75% of sodium zeolite and calcium zeolite of natural sodium and calcium zeolite particles of a majority between 65 μm and 125 μm in size at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce sulfur oxides in the stack gases;        (d) passing the stack gas flow from the second catalytic flow-through bed through a third catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles of a majority between 78 μm and 204 μm at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce nitrogen oxides in the stack gases and providing a stack gas flow exiting the third catalytic bed with at least 70% reduction in sulfur oxides, nitrogen oxides and carbon oxide; and        (e) purging residuals from the first catalytic bed, the second catalytic bed, and the third catalytic bed by intermittently passing liquid or gaseous nitrogen through the beds to remove solids and liquids collected from the stack gas flow by the beds.
In the alternative method of drying and cleaning stack gas described above, the voltages between the electrodes may be less than 34 volts, and the stack gas may have the flow sequentially circulated past the same or a different pair of electrodes and through the series of a first catalytic flow-through bed, a second catalytic flow-through bed, and a third catalytic flow-through bed.
The method also may remove from the gas flow at least 50% of mercury or at least 70% of mercury in all forms.
The electrodes in step (a) of the alternative method of cleaning and drying may be positioned in the gas flow downstream of a baghouse. The alternative method of drying and cleaning stack gas may also have the additional step of passing the gas flow through a venturi positioned downstream of the third catalytic flow-through bed to stabilize the gas flow through the beds.
The alternative method of drying and cleaning stack gas may also comprise a fourth catalytic flow-through bed of calcium zeolite comprising natural zeolite particles between 44 μm and 64 μm in size positioned in the stack gas flow after the pair of electrodes and before the first catalytic bed with an electrical charge on said fourth catalytic flow-through bed to separately collect bauxite compounds from the stack gas flow before passing through the first catalytic bed. The stack gas exiting a stack from the third catalytic bed may have at least 70% or 90% reduction in bauxite compounds, carbon oxides, sulfur oxides, nitrogen oxides, and mercury oxide compared to the stack gas flow delivered through the stack.
The alternative method of drying and cleaning stack gas may have the pair of electrodes positioned in the gas flow upstream of the first catalytic flow-through bed insulated from containment of the gas flow with applied direct voltage to ionize water vapor without creating substantial amounts of hydrogen gas in the gas flow and reduce moisture content of the gas flow through the catalytic flow-through beds to below, for example, 8% or 5% or a lower or different moisture content as desired.
The alternative method of drying and cleaning stack gas may comprise the additional step of passing the gas flow through a venturi positioned downstream of the third catalytic flow-through bed to stabilize the gas flow through the beds.
The alternative method of drying and cleaning stack gas may have at least two series of stack gas flows are provided in parallel to provide for the gas flow to passed a pair of electrodes inline and through a first catalytic bed, a second catalytic bed, and a third catalytic bed to enable at least one bed in series of beds can be purged while the stack gas flow continues to be dried and cleaned through a series of beds and optionally another pair of electrodes.
A second alternative method of drying and cleaning stack gases is disclosed comprising the steps of:                (a) passing a stack gas flow of less than 7% oxygen selected from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln by a pair of electrodes positioned generally inline in the gas flow and to ionize water vapor without creating substantial amounts of hydrogen gas and reduce moisture content of the gas flow through the catalytic flow-through bed as described below,        (b) passing the gas flow from the from the pair of electrodes through a first catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce carbon oxides from the stack gases and increase oxygen levels in the stack gases;        (c) passing the gas flow from the first catalytic flow-through bed through a second catalytic flow-through bed comprised of a blend between 25 and 75% of sodium zeolite and calcium zeolite of natural sodium and calcium zeolite particles at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce sulfur oxides from the stack gases and increase oxygen levels in the stack gases;        (d) passing the gas flow from the second catalytic flow-through bed through a third catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce nitrogen oxides in the stack gases and increase oxygen levels in the stack gas and providing gas exiting the third catalytic bed with at least 70% reduction in carbon oxides, sulfur oxides, and nitrogen oxides and greater than 15% oxygen.
The electrodes in step (a) may be positioned in the gas flow downstream of a baghouse and the voltage between the electrodes may be less than 34 volts. Also the second alternative method of drying and cleaning stack gas may have the pair of electrodes in the gas flow upstream of the first catalytic flow-through bed insulated from containment of the gas flow with an applied voltage to the electrodes to ionize water vapor in the gas flow and reduce moisture content of the gas flow in the first catalytic flow-through bed.
The second alternative method of drying and cleaning stack gas may have the stack gas flow sequentially circulated past the pair of electrodes and through the first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed also removes from the gas flow at least 50% or at least 70% of mercury in all forms.
The second alternative method of drying and cleaning stack gas may comprise the additional step of passing the gas flow through a venturi positioned downstream of the third catalytic flow-through bed to stabilize the gas flow through the beds.
The second alternative method of drying and cleaning stack gas may comprise in addition a fourth catalytic flow-through bed of calcium zeolite comprising natural zeolite particles between 44 μm and 64 μm in size positioned in the stack gas flow after the pair of electrodes and before the first catalytic bed with an electrical charge on said fourth catalytic flow-through bed to separately collect bauxite compounds from the stack gas flow before passing through the first catalytic bed. In this alternative method of drying and cleaning stack gas may have the stack gas exiting a stack from the third catalytic bed may have at least 70% or at least 90% reduction in bauxite compounds, carbon oxides, sulfur oxides, nitrogen oxides, and mercury oxide compared to the stack gas flow delivered through the stack.
The second alternative method of drying and cleaning stack gas may have at least two series of stack gas flows provided in parallel to pass the same or a different pair of electrodes inline to dry the stack gas by applying a voltage between the electrodes to ionize the water vapor without creating substantial amounts of hydrogen gas and through a series of a first catalytic bed, a second catalytic bed, and a third catalytic bed so that one stack gas flow can be dried and cleaned by the method described, while an alternative series of a first catalytic bed, a second catalytic bed, and a third catalytic bed may be purged for reuse.
A third alternative method of drying and cleaning stack gases is disclosed comprising the steps of:                (a) passing a stack gas flow selected from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln by at least two electrodes positioned generally inline in the gas flow and applying a D.C. voltage between the electrodes sufficient to ionize the water vapor in the stack gas flow without creating substantial amounts of hydrogen gas and reduce moisture content of the gas flow through the catalytic flow-through beds described below,        (b) passing the gas flow from the pair of electrodes through a first catalytic flow-through bed comprised of calcium zeolite with a porosity of a total surface area not greater than 1200 m2/g to reduce carbon oxides from the stack gases and increase oxygen levels in the stack gas;        (c) passing the gas flow from the first catalytic flow-through bed through a second catalytic flow-through bed comprised of a blend between 25% and 75% of sodium zeolite and calcium zeolite with a porosity of a total surface area not greater than 1200 m2/g to reduce sulfur oxides from the gas flow and increase oxygen levels in the gas flow; and        (d) passing the gas flow from the second catalytic flow-through bed through a third catalytic flow-through bed comprised of calcium zeolite comprising natural zeolite particles with a porosity of a total surface area not greater than 1200 m2/g to reduce nitrogen oxides and providing gas exiting the third catalytic bed with at least 70% reduction in sulfur oxides, nitrogen oxides and carbon oxides and greater than 15% oxygen.
The electrodes in step (a) of this third alternative method may be positioned in the gas flow downstream of a baghouse. This third alternative method of drying and cleaning stack gas may also provide the pair of electrodes in the gas flow upstream of the first catalytic flow-through bed and insulated from containment of the gas flow, and may apply D.C. voltage less than 34 volts to ionize water vapor in the gas flow and reduce moisture content of the gas flow in the first catalytic flow-through bed, preferably to below 8% or 5% or a lower or different moisture content as desired.
Note that in the method and alternative methods described above, the first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed may include other sizes of particles of zeolite as explained in more detail below.
In the third alternative method of drying and cleaning stack gas, an additional fourth catalytic flow-through bed of calcium zeolite comprising natural zeolite particles with a porosity of a total surface area not greater than 1200 m2/g may be positioned in the stack gas flow after the pair of electrodes and before the first catalytic bed with an electrical charge to separately collect bauxite compounds from the stack gas flow before passing through the first catalytic bed. This method of drying and cleaning stack gas may have the stack gas exiting a stack from the third catalytic bed with at least 70% or at least 90% reduction in bauxite compounds, carbon oxides, sulfur oxides, nitrogen oxides, and mercury oxide compared to the stack gas flow delivered to the stack.
This third alternative method of drying and cleaning stack may have at least two series of stack gas flows provided in parallel to pass the same or a different pair of electrodes positioned inline to ionize the water vapor in the stack gas without creating substantial amounts of hydrogen gas and through a first catalytic bed, a second catalytic bed, and a third catalytic bed so that one bed of stack gas flow can be dried and cleaned by the method described while another series of stack gas flow-through flow is purged.
This third alternative method of drying and cleaning stack gas may also comprise a fourth catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles between 44 μm and 64 μm in size positioned in the stack gas flow after the pair of electrodes and before the first catalytic bed, with an electrical charge on said fourth catalytic flow-through bed, to separately collect bauxite compounds from the stack gas flow before passing through the first catalytic bed. In this alternative method of drying and cleaning stack gas, the stack gas exiting a stack from the third catalytic bed may have at least 70% or at least 90% reduction in bauxite compounds, sulfur oxides, nitrogen oxides, mercury oxide, and carbon oxides compared to the stack gas flow delivered through the stack.
The method and alternative methods of drying and cleaning stack gas may comprise the additional step of passing the gas flow through a venturi positioned downstream of the third catalytic flow-through bed to stabilize the gas flow through the catalytic flow-through beds.
The method and alternative methods of drying and cleaning stack gas may have the stack gas flow sequentially circulated past the pair of electrodes and through the first catalytic flow-through bed, the second catalytic flow-through bed, and the third catalytic flow-through bed to also remove at least 50% or at least 70% of mercury in all forms from the gas flow.
Also disclosed is a fertilizer product produced by the steps of:                (a) passing a stack gas flow selected from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln by a pair of electrodes positioned generally inline in the gas flow with D.C. voltage applied between the electrodes to ionize water vapor, without creating substantial amounts of hydrogen gas, and reduce moisture content of the gas flow below, for example, 8% or 5% of moisture content in the gas flow,        (b) passing the gas flow from the pair of electrode through a first catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles of a majority between 44 μm and 64 μm in size, at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi, adapted to reduce carbon oxides in the stack gases;        (c) passing the gas flow from the first catalytic flow-through bed through a second catalytic flow-through bed comprised of a blend between 25 and 75% of sodium zeolite and calcium zeolite of natural sodium and calcium zeolite particles of a majority between 65 μm and 125 μm in size, at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi, adapted to reduce sulfur oxides in the stack gas flow;        (d) passing the gas flow from the second catalytic flow-through bed through a third catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles of a majority between 78 μm and 204 μm, at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi, to reduce nitrogen oxides in the stack gas flow and providing gas exiting the third catalytic bed with at least 70% reduction in carbon oxides, sulfur oxides, and nitrogen oxides; and        (e) purging residuals from the first catalytic bed, the second catalytic bed, and the third catalytic bed by intermittently passing nitrogen through the beds to remove residuals collected from the stack gases by the beds.
Also disclosed is fertilizer product produced by the steps of:                (a) passing a stack gas flow of less than 7% oxygen selected from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln by a pair of electrodes adapted to be positioned generally inline in the gas flow with a voltage applied to the electrodes to ionize water vapor in the gas flow without creating substantial amounts of hydrogen gas and reduce moisture content of the gas flow, for example, below at least 8%,        (b) passing the gas flow from the electrodes through a first catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce carbon oxides from the stack gases and increase oxygen levels in the stack gas;        (c) passing the gas flow from the first catalytic flow-through bed through a second catalytic flow-through bed comprised of a blend between 25% and 75% of sodium zeolite and calcium zeolite of natural sodium and calcium zeolite particles of at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce sulfur oxides from the stack gases and increase oxygen levels in the stack gas; and        (d) passing the gas flow from the second catalytic flow-through bed through a third catalytic flow-through bed comprised of calcium zeolite of natural zeolite particles at a temperature above the dew point between 125° F. and 500° F. and a pressure between 3 psi and 200 psi adapted to reduce nitrogen oxides in the stack gases and increase oxygen levels in the stack gas flow; and providing gas flow exiting the third catalytic bed with at least 70% reduction in sulfur oxides, nitrogen oxides and carbon oxides and greater than 15% oxygen.
Also disclosed is fertilizer product produced by the steps of:                (a) passing a stack gas flow from the group consisting of volatiles from combustion of coal or from combustion of natural gas or from a cement kiln by a pair of electrodes positioned generally inline in the gas flow and applying a D.C. voltage to ionize water vapor without creating substantial amounts of hydrogen gas and reduce moisture content of the gas flow through the catalytic flow-through beds,        (b) passing the gas flow from the pair of electrodes though a first catalytic flow-through bed comprised of natural calcium zeolite with a porosity of a total surface area of not greater than 1200 m2/g adapted to reduce carbon oxides in the stack gas;        (c) passing the gas flow from the first catalytic flow-through bed through a second catalytic flow-through bed comprised of a blend of natural sodium zeolite and natural calcium zeolite with a porosity of a total surface area of not greater than 1200 m2/g adapted to reduce sulfur oxides in the stack gas with the blend of sodium zeolite and calcium zeolite between 25% and 75%;        (d) passing the gas flow from second catalytic flow-through bed through third catalytic flow-through bed comprised of natural calcium zeolite with a porosity of a total surface area not greater than 1200 m2/g adapted to reduce nitrogen oxides in the stack gas and providing gas exiting the third catalytic bed with at least 70% reduction in sulfur oxides, nitrogen oxides, and carbon oxides; and        (e) purging residuals collected from the first catalytic bed, the second catalytic bed, and the third catalytic bed and collecting said residuals purged from the first catalytic bed, the second catalytic bed, and the third catalytic bed to provide a fertilizer product.
Also disclosed is a method of reducing moisture content in a gas flow comprising the steps of:                (a) positioning generally inline a pair of electrodes in a gas flow with moisture content to be reduced to ionize water vapor in the gas flow without creating substantial amounts of hydrogen gas;        (b) providing insulating containment of the gas flow, such as a pipe, from the electrodes; and        (c) applying voltage between the electrodes to ionize water vapor in the gas flow to reduce moisture content of the gas flow to at least 8% without creating substantial amounts of hydrogen gas.
In the various embodiments of the method, apparatus or fertilizer product, carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxide (NOX), sulfur dioxide (SO2) and nitrogen dioxide (NO2) in the gas stack flow may be reduced. The solid waste may also include nitrate salt formed by reaction of nitrogen and nitrogen compounds retained in the zeolite beds with available oxygen. Exit from the third catalytic bed may typically include excess oxygen from the reduction according in the first, second and third catalytic flow-through beds as described above. The apparatus may also include a product purged with liquid nitrogen.
In any case, the exiting stack gas with increased oxygen levels may be returned from the gas cleaning system to the burner where it is combusted with the coal or natural gas. The system may also include a solid waste draw for collecting the materials and drawing the waste material away from the gas cleaning section.
Other details, objects and advantages of the present invention will become apparent from the description of the preferred embodiments described below in reference to the accompanying drawings.


A metal-air battery comprising an emulsified or dispersed aqueous/ionic liquid two phase electrolyte system is provided. The two phase electrolyte system contains an aqueous phase and an ionic liquid phase wherein an amount of water exceeds the aqueous solubility of the ionic liquid. In one embodiment the metal-air battery is a lithium-air battery.

The present invention is directed to an electrolyte system for a metal-air battery having high capacity and recycle efficiency.
Lithium ion technology has dominated the market as energy source for small electronic devices and even hybrid electric vehicles. However, Li-ion batteries have insufficient theoretical capacity to be a power source for future high capacity generations of power sources capable to run an electric vehicle.
Metal-air batteries have been under investigation as advanced generation of high capacity energy sources that have the potential to power vehicular devices for distances comparable to present hydrocarbon based combustion engines. In a metal-air battery, the metal of the anode is oxidized and the resulting cation travels to the cathode zone containing a porous matrix of a material such as carbon, for example, where oxygen is reduced and the reduction product as oxide or peroxide combines with the metal cation to form the discharge product. Upon charge, this process is ideally reversed. Metal-air batteries are recognized to have potential advantageous properties over metal ion batteries because the cathodic material, oxygen, may be obtained from the environmental air atmosphere and thus the capacity of the battery would in theory be limited by the anodic metal supply. Thus, oxygen gas would be supplied continuously from outside the battery and battery capacity and voltage would be dependent upon the oxygen reducing properties and chemical nature of the discharge product formed.
Metal-air batteries typically include a metal electrode at which a metal is oxidized, an air electrode at which oxygen is reduced, and an electrolyte for providing ion conductivity. A significant limiting factor with conventional metal-air batteries is the evaporation of the electrolyte solution (i.e., the ionically conductive medium), particularly the evaporation of the solvent, such as water in an aqueous electrolyte solution and organic solvent in a non-aqueous electrolyte solution. Because the air electrode is required to be air permeable to absorb oxygen, it also may permit the solvent vapor to escape from the cell. Over time, the cell's operation efficiency is reduced due to solvent depletion.
Other problems associated with aqueous electrolyte batteries include water electrolysis during recharging and self-discharge. During recharge, a current is passed through the battery to reduce the oxidized fuel at the fuel electrode. Some of the current, however, electrolyzes the water resulting in hydrogen evolution (reduction) at the fuel electrode and oxygen evolution (oxidation) at the oxygen electrode as represented in the following equations:2H2O(l)+2e−→H2(g)+2OH−(aq)  Reduction:2H2O(l)→O2(g)+4H+(aq)+4e−  Oxidation:
In this manner, further aqueous electrolyte is lost from the battery. Additionally, the electrons that are consumed in reducing hydrogen are not available to reduce the oxide. Therefore, the parasitic electrolysis of the aqueous electrolyte reduces the long term cycle efficiency of the secondary battery.
To compensate for these problems, metal-air batteries with aqueous electrolyte solutions are typically designed to contain a relatively high volume of electrolyte solution. Some cell designs even incorporate means for replenishing the electrolyte from an adjacent reservoir to maintain the electrolyte level. However, either approach adds to both the overall size of the cell, as well as the weight of the cell, without enhancing the cell performance (except to ensure that there is a significant volume of electrolyte solution to offset evaporation of the water or other solvent over time). Specifically, the cell performance is generally determined by the fuel characteristics, the electrode characteristics, the electrolyte characteristics, and the amount of electrode surface area available for reactions to take place. But the volume of electrolyte solution in the cell generally does not have a significant beneficial effect on cell performance, and thus generally only detracts from cell performance in terms of volumetric and weight based ratios (power to volume or weight, and energy to volume or weight). Also, an excessive volume of electrolyte may create a higher amount of spacing between the electrodes, which may increase ohmic resistance and detract from performance.
Metals employed as oxidizable anode materials include any metal, alloy or metal hydrides thereof. For example, the fuel may comprise transition metals, alkali metal, and alkaline earth metals. Transition metals include, but are not limited to zinc, iron, manganese, and vanadium. The most common alkali metal is lithium but other alkali metals including sodium may be used. The other metals include, but are not limited to magnesium, aluminum, calcium and gallium. The metal electrode may comprise a metal, including elemental metal, metal bonded in a molecule or complex, including oxides, metal alloys, metal hydrides, etc.
The metal electrode may have any construction or configuration and may be a porous structure with a three-dimensional network of pores, a mesh screen, a plurality of mesh screens isolated from one another, or any other suitable electrode. The fuel electrode includes a current collector, which may be a separate element, or the body on which the fuel is received may be electroconductive and thus also be the current collector.
Lithium air batteries have the potential to supply 5-10 times greater energy density than conventional lithium ion batteries and have attracted much interest and development attention as a post lithium ion battery technology. For example, a nonaqueous lithium air battery which forms Li2O2 as discharge product theoretically would provide 3038 Wh/kg in comparison to 600 Wh/kg for a lithium ion battery having a cathodic product of Li0.5CoO2. However, in practice, the metal air technology in general and specifically current nonaqueous lithium air batteries suffer many technical problems which have prevented achievement of the theoretical capacity.
The capacity of the Li air battery is highly dependent upon the capacity of the cathode matrix to store the Li2O2 discharge product. Li2O2 is generally insoluble in conventional nonaqueous solvents employed in metal air batteries. Therefore, upon formation at the cathode matrix the Li2O2 precipitates and fills the surface porosity of the matrix thus preventing access to the vacant capacity of the matrix interior region. Moreover, Li2O2 is an insulator and therefore, once the surface of the matrix is coated, oxygen reduction is prevented and discharge terminated, i.e., the capacity of the battery is severely reduced in comparison to the theoretical capacity.
Furthermore, the cathode performance is strongly affected by the moisture content of ambient air. To simplify the cathode reaction mechanism, much effort has been devoted to battery systems having a supply of pure oxygen to the cathode. However, practically speaking, the structure, cost and equipment necessary for such a system detracts from the potential advantages. To be of utmost utility the metal air battery will require utility of ambient air.
In non-aqueous Li-air battery, water is detrimental to battery performance as described above. To date in spite of much experimental effort and study, no practically feasible method to develop a metal-air battery that functions efficiently with ambient air as oxygen source has been developed. One consideration may be to dry the ambient air in advance before introduction into the battery. However, in order to decrease the water content of air to an acceptable level (less than hundreds ppm), the dehydration system required would be too large. This will be also unrealistic for the installment of Li-air battery.
In view of the problems associated with non-aqueous electrolyte metal-air batteries, selecting an aqueous Li-air battery system may be considered. However, in an aqueous system, a highly concentrated alkaline solution is formed about the cathode which is corrosive to surrounding materials of construction. Also, in an aqueous system, water functions both as an electrolyte solvent and an active material. As a consequence the water content of the system is depleted during operation of the battery and requires a certain level of humidity in the environmental air supply to remain functional. However, this is not feasible for batteries operating in an environment of elevated or freezing temperatures. Thus water management is an element which is key to success of the aqueous Li-air battery.
The purpose of this invention is to develop new electrolyte solvents containing water that may have general utility for metal-air batteries and specifically for Li-air batteries. This novel electrolyte will be suitable for utility as a non-aqueous electrolyte solvent as well as aqueous electrolyte solvent.
Effort to overcome the problems listed above for metal-air batteries and to produce an efficient high capacity metal-air battery has received much attention.
Best et al. (U.S. 2014/0125292) describes lithium ion or lithium metal batteries containing electrolyte systems containing ionic liquids which are based on an anion containing a nitrile group. Dicyanamide is exemplary of an anion of this type. A water content of less than 1000 ppm in the ionic liquid is described as allowable. However, lower levels, "less than 750 ppm, less than 500, less than 250 ppm, . . . " are describes as preferred embodiments. Best does not describe a lithium air battery, does not describe a two phase aqueous/ionic liquid composition and does not disclose or suggest input of energy to a two phase liquid electrolyte system to form a dispersion or emulsion. It is believed that the water levels described in this reference are dissolved amounts and therefore a single phase electrolyte solvent is disclosed.
Khasin (U.S. 2013/0034781) describes a metal air battery having an aqueous electrolyte system. In a main embodiment, the battery is an aluminum-air battery. To avoid or control formation of metal oxide gel in the electrolyte, Khasin adds small particulates that prevent gel formation or with mechanical energy input, break the gel formed. The mechanical energy is applied by a sonicator that supplies ultrasonic vibration. Khasin does not disclose or suggest an ionic liquid as an electrolyte component and does not suggest an electrolyte having a two phase structure of ionic liquid and water.
Chiang et al. (U.S. Pat. No. 8,722,227) describes a redox flow energy device (flow cell) containing. Both lithium and sodium flow batteries are described as exemplary devices. Chiang describes application of "acoustic energy" the electrolyte flow system to prevent build-up of particles which would inhibit electrochemical performance. The carrier liquid may be aqueous or non-aqueous and ionic liquids are included in a listing of potential non-aqueous electrolyte solvents. A mixing fluid, not miscible with the electrolyte may be admitted to the flow cell to provide good mixing of the flowing redox composition. Chiang does not disclose or suggest a metal-air battery and does not disclose or suggest an electrolyte being a two phase aqueous-ionic liquid mixture.
Tsukamoto et al. (U.S. Pat. No. 6,797,437) describes a lithium ion secondary battery having an anode of lithium metal or porous material capable of absorbing and releasing lithium ions and a cathode of a complex oxide of lithium and a transition metal. The electrolyte is a soluble lithium salt in a two phase electrolyte system containing a carbonate and/or ether combination. The second phase is formed by a halogen containing flame retardant material. Tsukamoto is not concerned with intimate mixing of the two phases and describes having two distinct phases as advantageous because the halogen material does not interfere with the redox chemistry of the battery. Tsukamoto does not disclose an ionic liquid as an electrolyte component and does not disclose or suggest a two phase electrolyte having aqueous and ionic liquid phases. Further, Tsukamoto does not describe a metal-air battery.
Parker et al. (U.S. Pat. No. 4,377,623) describes a zinc-halogen electrochemical cell having inert electrodes which support oxidation of zinc metal added to the cell and bromine added to the cell. The electrolyte liquid is a two phase combination of an aqueous phase containing halide ions and an organic nitrile phase containing halogen. The performance of the system requires the formation of two distinct phases as layers and intimate mixing would not be operable. Parker is not directed to a metal-air battery and does not disclose or suggest an ionic liquid as an electrolyte solvent.
Yuan et al. (Journal of the Electrochemical Society, 161 (4) A451-A457 (2014)) describes a study of the electrochemical performance of cells containing room temperature ionic liquids (RTIL) with as much as 1.0% water. The solubility of water in the same RTIL (1-butyl-1-methyl-pyrrilidinium bis(trifluoromethanesulfonyl)imide) (BMP-TFSI) was shown to be 1.1407 wt % and therefore, a two phase system is not disclosed. Mixtures of 0.25 to 1.0 wt. % water in 1-butyl-1-methyl-pyrrolidinum bis(trifluoromethanesulfonyl)imide are prepared by ultrasonic mixing. However, these mixtures were prepared for conductivity and electrochemical characterization. Yuan does not disclose or suggest a metal-air battery with a two phase aqueous/ionic liquid electrolyte intimately mixed by an ultrasonic treatment.
Gasteiger et al. (Electrochemical and Solid State Letters, 15 (4) A45-A48 (2012)) describes a study of the effect CO2 and water on the performance of a lithium-air battery. The study showed that small amounts of water enhance capacity of the cell. Ionic liquids and/or a two phase aqueous/ionic liquid system is not disclosed or suggested.
Zhang et al. (Chem. Commun., 2010, 46, 1661-1663) describes a lithium air battery employing an electrolyte system composition of acetic acid/water and lithium acetate. The lithium acetate is also indicated to be formed by oxidation of the lithium metal anode. Construction of a lithium-air electrochemical cell (Li/PEO18LiTFSI/LTAP/HOAc—H2O—LiOAc/Pt-carbon black) is described and an energy density estimated to be 1.478 W h/kg. Zhang does not disclose or suggest an ionic liquid as an electrolyte component or a two phase (aqueous/ionic liquid) electrolyte system.
Friesen et al. (U.S. 2011/0305959) describes a metal-air battery having an ionic liquid based electrolyte. Metals suitable as anode materials include transition metals, alkali metals and alkali earth metals. Zinc air systems are most fully described. Friesen discusses the necessity to maintain a sufficient level of water in the electrolyte composition to drive the charge and discharge process and "tunes the ionic liquid" to contains water from 0.001 to 25% by adding a hydrophilic or hygroscopic additive which effectively absorbs water into the electrolyte. The amount of water absorbed depends on the nature and amount of the additive. Examples given for a zinc-air system include zinc chloride, zinc tetrafluoroborate zinc acetate and Zn(TFSI)2. Although Friesen discloses as much as 25% water, a 2 phase ionic liquid electrolyte system is never explicitly disclosed or suggested. Likewise, sonication to disperse water into the ionic liquid is neither disclosed nor suggested.
In spite of the significant ongoing effort there remains a need to develop and produce an effective electrolyte system for a high capacity metal-air battery useful especially for powering vehicles to distances at least equal to or competitive with current hydrocarbon fuel systems.

This patent is subject to a terminal disclaimer.

Water enhanced ionic liquid electrolytes for metal-air batteries

Toyota Motor Engineering & Manufacturing North America, Inc.


The invention relates to a sensor assembly for use in a bearing including at least one bearing cage configured to accommodate at least one rolling element of the bearing, the sensor assembly including a driven oscillator circuit providing a receiver, a function generator and a primary coil, and a passive oscillator circuit including a temperature dependent capacitance. The passive oscillator circuit is configured to be attached to the bearing cage such that the inductor coil interacts with the primary coil of the driven oscillator circuit. It is proposed that a directional coupler is provided in a signal line between a function generator and the primary coil of the system, wherein the directional coupler is arranged to output a signal reflected from the passive resonant circuit in the cage toward a tuned receiver receiving the feedback of the signals generated by the function generator.

It is known to provide bearings such as ball bearings or roller bearings with temperature sensors. For monitoring the bearing, heat generated at the interface of balls/rollers and the raceways is detected by a temperature sensor located as close as possible to this interface. This makes a cage of a bearing a desirable position for temperature measurement. However, a bearing cage is a rotating part and cannot be easily accessed and the available space is narrow. In particular for smaller bearings, it is difficult to integrate batteries or a generator into the bearing cage.
The document EP 1 849 013 B1 discloses a bearing having a cage equipped with a power receiving coil. A transmitter for sending a signal indicative of the sensed condition of the bearing to another antenna arranged on the outer race is integrated in the cage. However, this solution is feasible only for larger bearings with a cage capable of supporting the transmitter electronics.
Passive wireless temperature sensors for bearing cages have been proposed e.g. in the article "A Passive Wireless Temperature Sensor for Harsh Environment Applications", Sensors 2008, 7982-7995 by Ya Wang, Yi Jia, Qiushui Chen and Yanyun Wang. A passive oscillator circuit including a temperature dependent capacitance and an inductor can be arranged on a rotating element like a bearing such that the inductor coil interacts with a transmitter coil of a driven oscillator circuit. The temperature dependence of the capacitance results in a temperature dependence of the resonance frequency of the resonant circuit on the rotating element which can be measured. Similar systems have been investigated by S. Scott et al of the Purdue University.
The resonant circuit absorbs energy from the primary circuit with a coil such that the resonant frequency can be derived from an absorption peak in the frequency sweep. The method measures the energy missing at the oscillation frequency.
Typically, a function generator inserts a sine wave signal into a coaxial cable. At the location of the measurement, a T-splitter device splits the signal into a part going to the primary coil/transceiver coil and the part going to a receiver for carrying out the spectral analysis. The combination of primary coil and measurement coil in an area being measured absorbs a certain amount of energy at a certain frequency and this absorbed fraction is temperature-dependent. Whatever is left is supposed to reach the receiver. This method uses flux coupling between the coils as in a transformer. However, the method suffers from a low signal to noise ratio and from microphony caused by improper impedance matching.
Actually, only a part of the returning signal from the transceiver coil reaches the analyzing circuit of the receiver whereas another part returns into the generator and leads to a low signal to noise ratio.
The primary coil of the sensor is essentially a loop and thus a balanced-type electrical system, whereas the coaxial standard cable is unbalanced. The inherent issue is mismatching of the impedance of the system which causes microphony, i.e. the dependence on the outer circumstances such as vibrations or tolerances such that the output values will largely change. The microphony is mainly caused by reflected current flowing in the outer skin of a cable that can be influenced by touch or motion. This results in difficulties for calibration and reproducibility.

Sensor assembly for bearing with wireless temperature sensor


A method and device for controlling an automatic freewheeling function in a vehicle where a freewheeling function is active due to a prevailing freewheeling condition and where a control unit is programmed to:                predict that the vehicle soon will travel in a steep downhill slope that is steeper compared to a prevailing downhill slope;        simulate if less fuel will be consumed if the freewheeling function is inactivated in a a further position before the vehicle enters the steeper downhill slope, compared to if the vehicle enters the steeper downhill slope with the freewheeling function active; and        inactivate the freewheeling function in the further position, that is, before the vehicle enters the steeper downhill slope if the simulation shows that less fuel will be consumed.

The present invention relates according to an aspect thereof to a method and device for controlling inactivation of a freewheeling function in a vehicle.
The present invention also relates according to further aspects thereof to a computer program, computer program product and a storage medium to be used with a computer for executing said method.
An automatic vehicle transmission designed from planetary gears usually has one-way couplings between the planetary gear steps, which, when a propulsion engine is in drive, lock in the automatic gear position for torque transmission from the engine to the drive wheels, but which, when torque is transmitted in the opposite direction, i.e. at zero throttle and with the vehicle in motion, disengage and cause the vehicle to freewheel without engine braking, which, by utilizing the kinetic energy of the vehicle, yields lower fuel consumption than if the engine is busy braking.
A corresponding freewheel function for automated mechanical transmissions (AMT) is shown in WO 2005/084995. Here, the freewheel function is automatically activated when a predetermined vehicle condition is prevailing. This condition comprises at least traveling in a not too steep downslope and that there is no fuel demand from the driver (via the accelerator pedal) or from a cruise control in the vehicle. When the freewheel function is activated with a certain vehicle set speed, i. e. during a time period when the cruise control is active, and a certain over speed limit (VBCC set speed) is exceeded, then the freewheel function is automatically inactivated and the vehicle is automatically braked to a speed under said VBCC setspeed—When vehicle speed is below VBCC setspeed the freewheel function will be activated again if the right vehicle conditions are still prevailing.
WO2005/084995 further discloses that said VBCC setspeed can be automatically adjusted in dependence of road gradient in the near future, e. g. in dependence of that the prevailing downhill slope will end in a near future, which means increased VBCC setspeed in order to postpone inactivation of the freewheel function.
FIG. 1 discloses activation and inactivation of a freewheeling function when traveling a moderate downhill which soon changes to a steeper (downwards position B) downhill. According to prior art (see FIG. 1) if vehicle travel resistance becomes less than zero (moderate downhill) said freewheeling function will be activated when the vehicle is in position A. If said moderate downhill changes to a steep downhill (position B and downwards) the vehicle will gain speed quickly and when said over speed limit (VBCC set speed) is exceeded at position C, the freewheel function will automatically be inactivated and the vehicle will be automatically braked (from position C and downwards) to a speed under said VBCC setspeed.
It is desirable to address a technical problem of how to further decrease fuel consumption in a vehicle equipped with such a freewheel functionality.
An aspect of the present invention involves inactivating said-freewheeling at the right vehicle position. This can be done by a method starting from when a freewheeling function in a vehicle is active due to a prevailing freewheeling condition. This method is according to an aspect of the invention characterized in the steps of:                predicting that said vehicle soon will travel in a steep downhill slope that is steeper compared to a prevailing downhill slope,        simulating if less fuel will be consumed if said freewheeling function is inactivated before said vehicle enters said steeper downhill slope compared to if said vehicle enters said steeper downhill slope with said freewheeling function active,        inactivating said freewheeling function before said vehicle enters said steeper downhill slope if said simulation shows that less fuel will be consumed.
In one embodiment of the invention vehicle speed is starting to decrease before entering said steeper downhill slope and when inactivating said freewheeling function. In a further embodiment said inactivation of said freewheeling function comprises drivingly connecting a combustion engine to a transmission and driven wheels of said vehicle. In an even further embodiment of the invention said decrease of vehicle speed is performed by braking the vehicle with an engine braking device and/or an auxiliary braking device.
In another embodiment of the invention said simulation can also include simulating vehicle speed change with different possible gears engaged in said transmission and selecting the one gear that results in a smallest change of vehicle speed.
The device for controlling said automatic freewheeling relates to a vehicle that comprises an engine, an automated manual transmission, by said engine driven wheels, a freewheeling device and a control unit for controlling said engine, where said engine is arranged to drive said driven wheels via said automated manual transmission, and where said freewheeling device, said engine and said automated manual transmission are controlled by a control unit, where said control unit is arranged to perform the above method steps.

Method and device for controlling an automatic freewheeling function in a vehicle


A test device for a semiconductor memory device includes a clock frequency multiplier, a data input buffer, a test data generator and a data output buffer. The clock frequency multiplier multiplies an external clock signal having a relatively low frequency provided from an external test device to generate an internal clock signal having a relatively high frequency. The data input buffer buffers test pattern data provided in synchronization to the external clock signal to output the buffered test pattern data. The test data generator generates test data that is to be synchronized to the internal clock signal, using the outputted test pattern data based on a first or a second control signal. The data output buffer outputs the generated test data to a memory core of the semiconductor memory device. The test device generates various test data suitable for a memory test at a high operating speed.

1. Technical Field
This disclosure relates to a semiconductor memory test device and a test method using the same, and more particularly to semiconductor memory test devices that are capable of performing a high-speed memory test using various test data, and test methods using the same.
2. Description of the Related Art
Generally, a memory device is used to temporarily or permanently storing data and/or commands for computers, communication systems, image processing systems and so on. Examples of the memory device include semiconductor memory devices, tapes, magnetic disks and optical disks. Currently, the semiconductor memory device is the predominant memory device.
According to a data storage method, the semiconductor memory device is categorized into a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, and a read only memory (ROM). The storage capacities and operating speeds of these semiconductor memory devices are rapidly increasing.
Typically, in order to produce the semiconductor memory device, a circuit design process, a manufacturing process, and a test process are sequentially performed. The test process determines an increase or decrease in product reliability. In order to perform the test process on the semiconductor memory device, a predetermined test pattern is written to a cell of the semiconductor memory device, and then, the cell where the predetermined test pattern is written is read. By comparing the written test pattern with the read test pattern, the cell of the semiconductor memory device may be categorized as a defective cell or a non-defective cell.
An external test device inputs an external clock signal to the semiconductor memory device, receives the read test pattern from the semiconductor memory device, and determines whether the corresponding cell of the semiconductor memory device is defective or non-defective.
In order for the external test device to exactly determine whether data errors are being received from the semiconductor memory device, a clock frequency of the semiconductor memory device should be identical to a clock frequency of the external test device. The clock frequencies of semiconductor memory devices are typically much larger (faster) than the clock frequencies of the external test devices.
In particular, since there is a rapidly increasing trend for high-speed memory products that exceed 500 MHz in clock frequency, and because manufacturing costs for the external test device are high, it is difficult to efficiently maintain the affordability of external test devices that have a clock frequency that can match that of the high-speed semiconductor memory devices.
For example, if the maximum clock frequency of the external test device is about 250 MHz and the maximum clock frequency of the semiconductor memory device is about 500 MHz, it is a common practice to downwardly adjust the clock frequency of the semiconductor memory device to match the clock frequency of the external test device during the test process.
In order to efficiently raise the clock frequency of the external test device without having to replace the external test device, a clock doubling test mode has been proposed. The clock doubling test mode enables the semiconductor memory device to be internally tested with a high frequency clock by multiplying the external clock provided from the external test device using an exclusive-OR operation or a phase-locked loop (PLL) circuit.
FIG. 1 is a timing diagram illustrating a conventional process of frequency multiplication during a clock doubling test mode. Referring to FIG. 1, an external clock signal CLK and an inverted clock signal CLKB are provided as inputs of the exclusive-OR operation during the clock doubling test mode. The inverted clock signal CLKB has a phase difference of about 90 degrees with respect to the external clock signal CLK.
An internal clock signal INTERNAL CLOCK is generated by performing the exclusive-OR operation, and an operating frequency of the internal clock signal INTERNAL CLOCK is two times greater than that of the external clock signal CLK. Alternatively, the PLL circuit may be used so that the operating frequency of the external clock signal CLK is multiplied.
Although the clock doubling test mode may raise the operating frequency by multiplying the external clock signal CLK, the clock doubling test mode may not raise a bit-rate on a data input.
FIG. 2 is a timing diagram illustrating a conventional process of test data generation during a clock doubling test mode.
Referring to FIG. 2, the frequency of an internal clock signal INT CLOCK is two times greater than that of an external clock signal CLK. However, test pattern data D0 and D1 exist during both a rising edge and a falling edge of a data strobe (DS) signal, which is synchronized to the external clock signal CLK. Thus, in view of the internal clock signal INT CLOCK, it may regarded that the test pattern data D0 and D1 exist only during a rising edge of the internal clock signal INT CLOCK.
The inputted test pattern data are generated as test data D0, D0, D1 and D1. That is, the first and second test data are identical to each other, and the third and fourth test data are identical to each other.
In the conventional method, although the clock frequency of the internal clock signal may be increased, it is not possible to generate various test data used for performing the test of the semiconductor memory device. As a result, it is difficult to effectively utilize the advantage of a high-rate operating frequency of the internal clock signal.
Embodiments of the invention address these and other disadvantages.

Semiconductor memory testing device and test method using the same


A one-side electrogalvanized steel sheet with a distinguished susceptibility to a phosphate salt treatment and a distinguished appearance on the non-electrogalvanized side is produced by subjecting the non-electrogalvanized side of a steel sheet after one-side electrogalvanization in a galvanizing bath to an electrolytic peeling treatment using the non-electrogalvanized side of the one-side electrogalvanized steel sheet as an anode in an electrolytic peeling treatment bath containing 5 to 30% by weight of sodium sulfate as an electroconductive agent and at least 0.1% by weight of boric acid as a pH-controlling agent at a pH adjusted to a range of 5.0 to less than 9.0 as a posttreatment of the non-electrogalvanized side.

1. Field of the Invention
This invention relates to a process for producing a one-side electrogalvanized steel sheet and particularly to a posttreatment process for improving the susceptibility of the non-electrogalvanized side of one-side electrogalvanized steel sheet to a dip-type phosphate salt treatment, a spray-type phosphate salt treatment or the like.
In the present invention, a one-side electrogalvanized steel sheet means a steel sheet whose one side is electrogalvanized with zinc or alloy composed mainly of zinc or whose one side is subjected to a dispersive or composite plating, and concretely it means a steel sheet whose one side is electrogalvanized with a zinc system such as Zn-Ni system, Zn-Ni-Co system, Zn-Fe system, Zn-Ni-Fe system, Zn-Ni-Fe-Cr system, Zn-Mn system, Zn-Mg system, Zn-Bi system, Zn-Cr system, Zn-Ni-Cr system, Zn-Ni-SiO.sub.2 system, Zn-Ni-Cr-SiO.sub.2 system or Zn-Ni-BaCrO.sub.4 system.
2. Prior Art
One-side electrogalvanized steel sheets are used mainly as outer casings for automobiles, and generally it is a usual practice to apply a phosphate salt treatment to the non-electrogalvanized side of a one-side electrogalvanized steel sheet as a coating treatment before coating of the non-electrogalvanized side with a paint.
In the phosphate salt treatment, it is necessary to clean the non-electrogalvanized side in a well known manner to bring the non-electrogalvanized side into such a state as not to prevent nuclear generation and growth of crystals in chemical conversion coating. However, the non-electrogalvanized side of the one-side electrogalvanized steel sheet is corroded with the galvanizing solution in the process for one-side electrogalvanization and as a result the corrosion products formed on the surface inhibit the nuclear generation, etc. of crystals in the chemical conversion coating. In order to obtain a good chemical conversion coatability on the non-electrogalvanized side, it is thus necessary to prevent the formation of the corrosion products or remove the formed corrosion products.
The following procedures have been proposed to solve these problems.
A process for removing corrosion products formed on the non-electrogalvanized side by a mechanical means, for example, by grinding with a brush, etc. after the one-side electrogalvanization [Japanese Patent Application Kokai (Laid-open) Nos. 59-126788 and 60-43499], where the non-electrogalvanized side has scars due to the grinding with a brush and there is still a problem on the appearance.
A process for treating the non-electrogalvanized side with an aqueous oxalic acid solution after the one-side electrogalvanization [Japanese Patent Application Kokai (Laid-open) No.60-200974], where the process is effective for preventing the non-electrogalvanized side from discoloration, but fails to remove a trace amount of galvanization metals such as Zn, etc. deposided on the non-electrogalvanized side during the one-side electrogalvanization, and thus the improvement effect on the susceptibility to the phosphate salt treatment is not satisfactory.
A process for applying a peeling treatment to the non-electrogalvanized side by electrolysis using the non-electrogalvanized side as an anode, for example, using the non-electrogalvanized side of one-side electrogalvanized steel sheet 1 as anode in an electrolytic treatment tank 9 as shown in FIG. 2, after the one-side electrogalvanization [Japanese Patent Application Kokai (Laid open) Nos. 58-133395 and 59-96292]. In FIG. 2, the non-electrogalvanized side of one-side electrogalvanized steel sheet is counterposed to an electrode 15, numeral 16 is press rolls and numeral 17 is electroconductive rolls. The process for applying the peeling treatment is satisfactory in that a good chemical conversion coating is obtained in a spray-type chemical conversion treatment which has been hitherto used by automobile makers. However, it is not satisfactory in a dip-type chemical conversion treatment which has been recently increased to a great degree. That is, since the process for applying the peeling treatment does not specify a combination of the concentration of agent, which is necessary for ensuring the electroconductivity in the treating bath, and pH-controlling agent, the performance of the treating bath is unstable in peeling by electrolysis. This results in problems such that the process cannot produce a steel sheet with a good appearance of the peeled surface and a good performance in the dip-type chemical conversion treatment.
A process for applying a peeling treatment to the non-electrogalvanized side by electrolysis using the non-electrogalvanized side as an anode in a phosphoric acid-based bath after the one-side electrogalvanization [Japanese Patent Application Kokai (Laid-open) No. 58-181889], where the pH stability is improved by using phosphoric acid which is a weak acid, and a steel sheet with a comparatively better susceptibility to a phosphate salt treatment can be obtained, but there is an environmental pollution problem due to an inevitable discharge of waste phosphoric acid-based bath in the actual operation when the peeling bath is renewed.

Process for producing one-side electrogalvanized steel sheet with distinguished susceptibility to phosphate salt treatment and distinguished appearance on the non-electrogalvanized side


A radio base station includes a mobile communication system, a first relay node and a first radio base station connected via a radio bearer, a second relay node, and a second radio base station connected via a radio bearer. The first radio base station and the second radio base station are connected via a bearer, in which a mobile station is configured so as to conduct a handover process between a first and second state. In the first state a radio bearer is established with the first relay node in order to communicate. In the second state a radio bearer is established with the second relay node in order to communicate. The mobile station is configured such that in the handover process, control signals are transmitted and received via the radio bearer between the first relay node, first radio base station, second radio base station, and second relay node.

1. Technical Field
The present invention relates to a mobile communication system.
2. Background Art
A mobile communication system of the LTE scheme (Release.8) defined by the 3GPP, as illustrated in FIG. 8, is configured such that when a handover process by a mobile station UE is carried out from a radio base station eNB#1 to a radio base station eNB#2, control signals involved in the handover process are transmitted and received between the radio base station eNB#1 and the radio base station eNB#2 via an X2 bearer that has been installed between the radio base station eNB#1 and the radio base station eNB#2.
As illustrated in FIG. 8, the radio base station eNB#1 and the radio base station eNB#2 include a network layer 1 (NW L1) function, a network layer 2 (NW L2) function, an IP (Internet Protocol) layer function, and an SCTP (Stream Control Transmission Protocol) layer function as the X2 bearer functions for establishing the X2 bearer.
In the LTE-advanced mobile communication system, which is a next-generation communication scheme of the LTE scheme, "relay nodes (RN)" including the same functions as a radio base station eNB can establish a connection between a mobile station UE and the radio base station eNB.
However, the conventional mobile communication system has a problem in that there is no regulation for how handover processes by the mobile station UE are to be handled when the relay nodes RN have been connected.