A crystalline titanosilicate catalyst which is usable as a catalyst in the oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group, a process for producing the catalyst, and a process for producing an oxidized compound by an oxidation reaction using the catalyst. It has been found that a crystalline titanosilicate having a structural code of MWW effectively functions as a catalyst in an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent, thereby to highly selectively provide an intended oxidized compound.

The present invention relates to a crystalline titanosilicate catalyst having a structural (or framework type) code of MWW, which is usable as a catalyst in an oxidation reaction of the carbon-carbon double bond of a compound having a carbon-carbon double bond and at least one other functional group. The present invention also relates to a process for producing such a catalyst and a process for producing an oxidized compound using this catalyst.
More specifically, the present invention relates to a crystalline titanosilicate catalyst having a structural code of MWW, which is usable as a catalyst in an oxidation reaction of the carbon-carbon double bond of a compound having a carbon-carbon double bond and at least one other functional group using a peroxide as an oxidizing agent; a process for producing such a catalyst; and a process for producing an oxidized compound (particularly, an epoxy compound) comprising performing an oxidation reaction of the carbon-carbon double bond of a compound having a carbon-carbon double bond and at least one other functional group in the presence of the catalyst.
In general, xe2x80x9czeolitexe2x80x9d is a generic term for crystalline and porous aluminosilicates for, and the basic unit of the structure of a zeolite is (SiO4)4xe2x88x92 or (AlO4)5xe2x88x92 having a tetrahedral structure. However, it has recently been clarified that a structure peculiar to or analogous to such a zeolite is also present in many other oxides such as aluminophosphate.
In addition, according to the International Zeolite Association (hereinafter, simply referred to as xe2x80x9cIZAxe2x80x9d) who defines the zeolite in W. Meier, D. H. Meier, D. H. Olxon and Ch. Baerlocher, Atlas of Zeolite Structure Types, 4th Edition, Elsevier (1996) (hereinafter, simply referred to as xe2x80x9cAtlasxe2x80x9d), substances having the same structure, other than aluminosilicate, are described as an object substance in prescribing the structure, and these substances are called xe2x80x9czeolite-like materialsxe2x80x9d in the Atlas.
The history of this definition is described in detail in Yoshio Ono and Takeaki Yajima, Zeolite no Kagaku to Kogaku (Science and Engineering of Zeolites), pp. 1-2, published by Kodansha (Jul. 10, 2000).
In the present specification, the definition of xe2x80x9czeolitexe2x80x9d follows the above definition as described in Yoshio Ono and Takeaki Yajima, Zeolite no Kagaku to Kogaku (Science and Engineering of Zeolite), published by Kodansha (Jul. 10, 2000), where the term xe2x80x9czeolitexe2x80x9d may include not only aluminosilicates but also substances (such as titanosilicate) having a structure analogous to aluminosilicate.
In the present specification, the structures of zeolite and zeolite-like materials are denoted by a structural code, using three alphabetic capital letters, approved by IZA and originated in the standard substance which had first been used for the clarification of the structure thereof. The structural codes includes those contained in Atlas and those approved in the 4th edition, et seq.
In the present specification, the terms xe2x80x9caluminosilicatexe2x80x9d and xe2x80x9ctitanosilicatexe2x80x9d are not limited at all by the properties and/or states thereof (such as crystalline or amorphous, or porous or not porous). Therefore, in the present specification, these terms denote xe2x80x9caluminosilicatesxe2x80x9d and xe2x80x9ctitanosilicatesxe2x80x9d of all properties, unless specifically indicated otherwise.
In the present specification, the term xe2x80x9cmolecular sievexe2x80x9d means an activity or operation for classifying molecules by the size thereof, and the term also means a substance having such a function. zeolite is also included in the definition of a molecular sieve. The details thereon are described in the portion relating to xe2x80x9cmolecular sievexe2x80x9d in Hyojun Kagaku Yogo Jiten (Standard Chemical Glossary), edited by the Chemical Society of Japan, published by Maruzen (Mar. 30, 1991).
In recent years, various studies have been made on the oxidation reactions of organic compounds by using a titanosilicate which is a zeolite, as a catalyst, and using a peroxide as an oxidizing agent. Among these, a catalyst named xe2x80x9cTS-1xe2x80x9d, which is a crystalline titanosilicate, has been found to show an activity in an oxidation reaction using various peroxides, after the process for synthesizing the same was disclosed in U.S. Pat. No. 4,410,501, and TS-1 has been applied to various reactions. Specific examples thereof include the method disclosed in JP-B-4-5028 (xe2x80x9cJP-Bxe2x80x9d as used herein means an xe2x80x9cexamined Japanese Patent publicationxe2x80x9d), where TS-1 is used as a catalyst in the epoxidation of an olefin compound using hydrogen peroxide or an organic peroxide as an oxidizing agent.
The structural code of the titanosilicate TS-1 is xe2x80x9cMFIxe2x80x9d, which is the same code as the structural code of a representative synthetic zeolite ZSM-5, and TS-1 contains a ring structure containing ten (10) oxygen atoms (as described in Yoshio Ono and Takeaki Yajima, Zeolite no Kagaku to Kogaku, p. 4, published by Kodansha). As TS-1 has a relatively small pore size of 0.51 nm to 0.56 nm in terms of a calculated value therefor, the scope of olefin compounds which can be epoxidized by using TS-1 is limited. Further, both of the rate of the diffusion of an olefin compound as a reaction starting material into the inside of a pore and the rate of the effusion of an epoxy compound as a reaction product from the pore are low, so that a reaction activity which is sufficiently high, in view of the industrial use of TS-1, cannot be achieved in many cases. Furthermore, there is a problem such that a ring-opening reaction of the epoxy group of an epoxy compound as a reaction product is liable to occur, and the resultant selectivity is disadvantageously decreased.
On the other hand, JP-A-7-242649 (xe2x80x9cJP-Axe2x80x9d as used herein means xe2x80x9cunexamined Japanese Patent publicationxe2x80x9d) discloses a method of performing an epoxidation reaction of an olefin compound by using a crystalline titanium-containing molecular sieve having a structure similar to aluminum-free zeolite Beta (structural code: *BEA) as a catalyst and by using hydrogen peroxide or an organic peroxide as an oxidizing agent.
Since the *BEA has a large pore diameter as compared with that of the structural code of MFI for the titanosilicate TS-1, an effect of enabling a reaction of a sterically bulky compound or an effect of elevating the diffusion rate to thereby improve the resultant reaction rate was expected. In some examples of the above-mentioned Patent publication, a compound which does not react even in the case using the titanosilicate TS-1 can be actually oxidized. However, there are caused problems that the conversion of an oxidizing agent is low when hydrogen peroxide is used as the oxidizing agent for the epoxidation reaction, and that a ring-opening reaction of the epoxide is caused to produce a corresponding glycol, and as a result, the resultant selectivity is decreased. Further, in the case of the molecular sieve as described in this Patent publication, the decreasing rate of activity is rather high. That is, the catalyst life is short, and therefore it is necessary to repeat the regeneration of the catalyst frequently, whereby this point seriously hinders the implementation of such a molecular sieve on an industrial scale.
On the other hand, in recent years, synthetic zeolites having a structural code of MWW, which is different from those of MFI or *BEA, are attracting attention. The process for producing the same is disclosed, for example, in JP-A-63-297210.
Further, according to Peng Wu, Takashi Tatsumi and Takayuki Komatsu, Chemistry Letters, 774 (2000), it has been reported that when a crystalline titanosilicate having the structural code of MWW and containing a titanium atom in the crystal structure thereof is produced, and cyclohexene is oxidized by using this crystalline titanosilicate as a catalyst and by using hydrogen peroxide, cyclohexene oxide can be produced.
However, the yield of the intended product is rather low, while both of the resultant epoxide and diol are produced in a considerably large amount, whereby a tendency of selectively providing any of these compounds is not observed. Therefore, there is a caused problem when this method is intended to be utilized industrially.
As described hereinabove, various proposals have been made for conducting the oxidation reaction of an olefin compound by using a titanosilicate as a catalyst and by using a peroxide as an oxidizing agent. However, industrially practicable techniques are rather limited, and further, in any of the above-mentioned cases, only an oxidation reaction of a simple compound having a carbon-carbon double bond is disclosed. There has not yet been reported a titanosilicate which is usable as a catalyst in the oxidation reaction of a compound not only having a carbon-carbon double bond and but also having at least one other functional group.
An object of the present invention is to provide a crystalline titanosilicate catalyst which is usable as a catalyst in a selective oxidation reaction of the carbon-carbon double bond of a compound having a carbon-carbon double bond and at least one other functional group.
Another object of the present invention is to provide a process for producing such a titanosilicate catalyst, and to provide a process for producing an oxidized compound by an oxidation reaction using the catalyst.
As a result of earnest study for solving the above-mentioned problems, the present inventors have found that a crystalline titanosilicate catalyst having a structural code of MWW can effectively function as a catalyst for a reaction wherein the carbon-carbon double bond of a compound having a carbon-carbon double bond and at least one other functional group is oxidized by using a peroxide, so as to provide an intended oxidized compound highly selectively. The present invention has been accomplished based on this discovery.
More specifically, the present invention, in an aspect, is a crystalline MWW-type titanosilicate catalyst, for producing an oxidized compound, which is usable in producing an oxidized compound by an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent. The catalyst has an MWW structure and is represented by the following (chemical) composition formula (1):
xTiO2.(1xe2x88x92x)SiO2xe2x80x83xe2x80x83Composition formula (1)
(wherein x is a number of 0.0001 to 0.2).
The present invention, in a second aspect, is a crystalline MWW-type titanosilicate catalyst for producing an oxidized compound, which is usable in producing an oxidized compound by an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent. The catalyst has an MWW structure and is represented by the following composition formula (2):
xTiO2.yM2O3.(1xe2x88x92xxe2x88x922y)SiO2xe2x80x83xe2x80x83Composition formula (2)
(wherein M represents at least one element selected from the group consisting of aluminum, boron, chromium, gallium and iron, x is a number of 0.0001 to 0.2 and y is a number of 0.0001 to 0.1).
The present invention in a third aspect is a process for producing the crystalline MWW-type titanosilicate catalyst for producing an oxidized compound according to the present invention in the above-mentioned first or second aspect thereof.
The present invention in a fourth aspect is a process for producing an oxidized compound, comprising: performing an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent in the presence of the crystalline MWW-type titanosilicate catalyst for producing an oxidized compound according to the present invention in the first or second aspect.
Best Mode for Carrying Out the Invention
Hereinbelow, the present invention will be described in detail with reference to the accompanying drawings as desired. In the following description, xe2x80x9c%xe2x80x9d and xe2x80x9cpart(s)xe2x80x9d representing a quantitative proportion or a ratio are based on mass, unless otherwise noted specifically.
At first, the present invention in the first aspect and the present invention in the second aspect will be described.
The present invention in the first aspect is a crystalline MWW-type titanosilicate catalyst for producing an oxidized compound, which is usable in producing an oxidized compound by an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent. The catalyst has an MWW structure and is represented by the following composition formula (1):
xTiO2.(1xe2x88x92x)SiO2xe2x80x83xe2x80x83Composition formula (1)
(wherein x is a number of 0.0001 to 0.2).
The present invention in a second aspect is a crystalline MWW-type titanosilicate catalyst for producing an oxidized compound, which is usable in producing an oxidized compound by an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent. The catalyst has an MWW structure and is represented by the following composition formula (2):
xTiO2.yM2O3.(1xe2x88x92xxe2x88x922y)SiO2xe2x80x83xe2x80x83Composition formula (2)
(wherein M represents at least one element selected from the group consisting of aluminum, boron, chromium, gallium and iron, x is a number of 0.0001 to 0.2 and y is a number of 0.0001 to 0.1).
In the crystalline MWW-type titanosilicate catalyst for producing an oxidized compound according to the present invention in the first aspect, the ratio of constituent units TiO2 and SiO2 present in the catalyst can be specified by the molar ratio therebetween. Therefore, xe2x80x9cxxe2x80x9d means the molar ratio of TiO2 present in the titanosilicate, and (1xe2x88x92x) means the molar ratio of SiO2 also present in the titanosilicate. In the other words, the ratio x/(1xe2x88x92x) merely shows the molar ratio of titanium/silicon, and this ratio does not exclude the presence of at least one other element in the above-mentioned crystalline MWW-type titanosilicate for producing an oxidized compound.
In the composition formula (1), the range of x is from 0.0001 to 0.2, preferably from 0.005 to 0.2, more preferably from 0.01 to 0.1. In addition to the titanium species which have been introduced into the framework by substituting with silicon, a titanium species may be present at a site outside the crystal framework (or skeleton). For example, a 6-coordination titanium species or an anatase-like titanium oxide may be present together with the above-mentioned titanium species. However, such a titanium species outside the framework generally has a tendency-such that it promotes a side reaction or narrows the pores in the titanosilicate so as to inhibit the diffusion of a substance relating to the reaction. Therefore, the titanium species present at a site outside the crystal framework, if present, may preferably be present in a smaller amount.
In general, the x specified in the composition formula (1) shows an estimated ratio of titanium contained within the framework. In practice, when titanium is present outside the framework in addition to titanium within the framework, it is difficult to precisely quantitate the titanium contained within the framework. In general, for example, in the ultraviolet-visible absorption spectrum of a titanosilicate, the absorption in the vicinity of 210 nm is assigned to titanium within the framework, the absorption in the vicinity of 260 nm is assigned to a 6-coordination titanium species outside the framework, and the absorption in the vicinity of 330 nm is assigned to an anatase-like titanium species. Therefore, if an absorption is present in the vicinity of 210 nm, this absorption reveals that the titanosilicate corresponding to the spectrum contains titanium within the framework. Actually, the titanosilicate catalyst according to the present invention in the first aspect has an absorption in the vicinity of 220 nm, and this absorption reveals the presence of titanium within the framework. However, when another absorption is present at other wavelengths, it is difficult to quantitatively discuss the ratio of these titanium species present in the titanosilicate, even in a case where other means such as nuclear magnetic resonance method or infrared absorption method is combined with the above ultraviolet-visible absorption spectrum.
Only one clear fact is that the value of the molar ratio of titanium to silicon calculated from the ratio between titanium and silicon determined by the component analysis such as elemental analysis, is the maximum value of the amount of titanium contained within the framework. As described above, it is difficult to directly determine the molar ratio of titanium contained within the framework. Therefore, in the present invention, the molar ratio of titanium to silicon calculated by the component analysis as x in the composition formula (1) is for convenience used as the molar ratio of titanium contained within the framework.
The crystalline titanosilicate catalyst according to the present invention in the first aspect having a structural code of MWW wherein silicon is partially substituted with titanium may contain an element other than titanium, silicon and oxygen, as long as such an element does not greatly cause an adverse effect on the reactivity of the catalyst. In a case where the catalyst according to the present invention in the first aspect is produced by a production process using boron as a structure supporting agent, as described hereinafter, a slight amount of boron may remain in the catalyst in many cases, even if an operation for removing boron is performed. However, boron in a small amount does not have any serious effect on the reactivity of the catalyst, and therefore, boron can be present in the catalyst in a substantial amount. In principle, other trivalent metals such as aluminum, gallium, iron and chromium may also be used as a structure supporting agent in place of boron, and in such a case, these elements may sometimes remain within and outside the framework.
In this case, there is formed a crystalline MWW-type titanosilicate catalyst for producing an oxidized compound according to the present invention in the second aspect. That is, the present invention in the second aspect is a crystalline MWW-type titanosilicate catalyst for producing an oxidized compound, which is usable in producing an oxidized compound by an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent. The catalyst has an MWW structure and is represented by the following composition formula (2):
xTiO2.yM2O3.(1xe2x88x92xxe2x88x922y)SiO2xe2x80x83xe2x80x83Composition formula (2)
(wherein M represents at least one element selected from the group consisting of aluminum, boron, chromium, gallium and iron, x is a number of 0.0001 to 0.2 and y is a number of 0.0001 to 0.1).
In the above composition formula (2), the number xe2x80x9cxxe2x80x9d has the same meaning as in the composition formula (1) and the number xe2x80x9cyxe2x80x9d is also a molar ratio of constituent unit M2O3 present in the catalyst. Similarly to the composition formula (1), the ratio of x/(1xe2x88x92xxe2x88x922y) represents merely a molar ratio of xe2x80x9ctitaniumxe2x80x9d/xe2x80x9csiliconxe2x80x9d and the ratio of y/(1xe2x88x92xxe2x88x922y) represents merely a ratio of xe2x80x9cat least one element in total selected from the group consisting of aluminum, boron, chromium, gallium and ironxe2x80x9d/xe2x80x9csiliconxe2x80x9d. Accordingly, these ratios do not exclude the presence of other elements in the catalyst according to the present invention in the second aspect. In the composition formula (2), y is a number of 0.0001 to 0.1, preferably 0.0001 to 0.05, more preferably 0.0001 to 0.03.
In the composition formula (2) according to the present invention in the second aspect, the number y can be determined from the component analysis values in a similar manner as in the case of the number x in the composition formula (1) according to the present invention in the first aspect. The form or state of the presence of M2O3 may be either within the framework or outside the framework. M is at least one element selected from the group consisting of aluminum, chromium, gallium and iron, and has a valence number of 3.
As used in the synthesis of MCM-22, an alkali metal such as sodium and potassium can be generally expected to function as a mineralizing agent, and therefore, the alkali metal may be used in the production of the catalyst according to the present invention in the first or second aspect for the purpose of accelerating the crystallization. However, in general, the alkali metal has a possibility of inhibiting the catalytic function of the crystalline titanosilicate, and therefore, it is preferred to remove the alkali metal from the crystalline titanosilicate by ion exchange or the like.
The MWW structure, which is one known structure of molecular sieves, is characterized in that it has a pore comprising a ring structure containing 10 oxygen atoms and has a super cage (0.7xc3x970.7xc3x971.8 nm). This structure has been approved by IZA after the publication of the above-mentioned Atlas. The details of the structure can be inspected, for example, on the homepage (http://www.iza-structure.org/) of the IZA Structure Commission (as of September, 2000). Examples of known molecular sieves having this structure may include MCM-22 (Science, Vol. 264, 1910 (1994)), SSZ-25 (European Patent No. No. 231860), ITQ-1 (Chem. Mater., Vol. 8, 2415 (1996) and J. Phys. Chem. B, Vol. 102, 44 (1998)), ERB-1 (European Patent No. No. 203032) and PSH-3 (U.S. Pat. No. 449409). The molecular sieve having structural code of MWW can be identified by the pattern of its characteristic X-ray diffraction (hereinafter, simply referred to as xe2x80x9cXRDxe2x80x9d). The XRD pattern may also be available as a simulation pattern of ITQ-1, for example, on the above-mentioned homepage. Representative examples of the diffraction line may include those shown in Table 1 below.
The present invention in the third aspect will be described below. The present invention in the third aspect is a process for producing a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound, comprising the following first and second steps:
First step
a step of heating a mixture comprising a template compound, a titanium-containing compound, a boron-containing compound, a silicon-containing compound and water, to thereby obtain a precursor;
Second step
a step of calcining the precursor obtained in the first step, to thereby obtain a crystalline titanosilicate.
The crystalline MWW-type titanosilicate catalyst for providing an oxidized compound according to the present invention can also be synthesized by a conventionally known direct synthesis method or a post-synthesis method such as an atom-planting method (with respect to the details of the atom-planting method, Yoshio Ono and Tastuaki Yashima xe2x80x9cScience and Engineering of zeolitesxe2x80x9d (Jul. 10, 2000), p 142, Kodansha; and Peng Wu, Takayuki Komatsu, Tatsuaki Yashima, Shin-ichi Nakata, and Hiroshi Shouji, xe2x80x9cModification of mordenite acidity by isomorphous substitution of trivalent cations in the framework sites using the atom-planting methodxe2x80x9d Microporous Materials 12 (1997) 25-37 may be referred to.). In the case of the atom-planting method, the catalyst may be synthesized, for example, by preparing a molecular sieve having a MWW structure containing boron or aluminum, removing at least a part of boron or aluminum through a water vapor treatment or the like, and then contacting the resultant residue with a titanium compound such as titanium trichloride.
A more efficient production process for the MWW-type titanosilicate catalyst may include a production process according to the present invention in the third aspect. That is, the process for producing a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound according to the present invention in the third aspect is a production process for a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound, characterized in that the production process comprises two steps, i.e., a step of heating a mixture comprising a template compound, a titanium-containing compound, a boron-containing compound, a silicon-containing compound and water, to thereby obtain a precursor; and a step of calcining the resultant precursor, to thereby obtain a crystalline MWW-type titanosilicate for producing an oxidized compound.
At first, the above first step is described below. The first step in the process for producing the crystalline titanosilicate of the present invention in the third aspect is a step of heating a mixture comprising a template compound, a titanium-containing compound, a boron-containing compound, a silicon-containing compound and water, to thereby obtain a precursor.
The xe2x80x9ctemplate compoundxe2x80x9d as used herein is a compound having a function of, in the synthesis of zeolite having an MWW structure, determining the structure thereof and, particularly, of determining the shape of the pore. The template compound is not particularly limited, as long as it can be removed later by calcining. Examples thereof may generally include nitrogen-containing compounds. Specific examples of such a nitrogen-containing compound may include piperidine, hexamethyleneimine and/or a mixture thereof, but the template compound usable in the present invention is not limited to these specific compounds.
The titanium-containing compound which is usable in the first step is not particularly limited, as long as the titanium-containing compound can provide a gel-type product. Specific examples of the titanium-containing compound may include titanium oxide, titanium halide and tetraalkyl orthotitanates, but the titanium-containing compound usable in the present invention is not limited to these specific compounds. Among these, in view of easiness in the handling thereof, titanium halide and tetraalkyl orthotitanates are preferred. More specifically, titanium tetrafluoride, tetraethyl orthotitanate, tetrapropyl orthotitanate and tetrabutyl orthotitanate may suitably be used.
The boron-containing compound which is usable in the first step is not particularly limited. Preferred specific examples thereof may include boric acid, which can also be used in the form of a borate such as sodium borate.
The silicon-containing compound which is usable in the first step is not particularly limited. Specific examples thereof may include silicic acid, silicic acid salt, silicon oxide, silicon halide, fumed silicas, tetraalkyl orthosilicates and colloidal silica. In any of these cases, a silicon-containing compound having a high purity is preferred. More specifically, the silicon-containing compound may preferably have an alkali metal content such that the total moles of the alkali metal components is smaller than the moles of titanium, preferably {fraction (1/10)} times or less the moles of titanium, more preferably {fraction (1/100)} times or less the moles of titanium. Among these, in the case of colloidal silica, one having a smaller alkali content is preferred.
The ratio between titanium and silicon in the mixture to be used in the first step may preferably be 0.001 to 0.3:1 (titanium:silicon), more preferably 0.005 to 0.2:1 (titanium:silicon), particularly preferably 0.01 to 0.2:1 (titanium:silicon), in terms of the molar ratio therebetween.
The ratio between boron and silicon in the mixture to be used in the first step may preferably be 0.3 to 10:1 (boron:silicon), more preferably 0.5 to 5:1 (boron:silicon), particularly preferably 1 to 2:1 (boron:silicon), in terms of the molar ratio therebetween.
The ratio between water and silicon in the mixture to be used in the first step may preferably be 5 to 200:1 (water:silicon), more preferably 15 to 50:1 (water:silicon), in terms of the molar ratio therebetween.
The ratio between the template compound and silicon in the mixture to be used in the first step may preferably be 0.1 to 5:1 (template compound:silicon), more preferably 0.3 to 3:1 (template compound:silicon), particularly preferably 0.5 to 2:1 (template compound:silicon), in terms of the molar ratio therebetween.
These ratios of the mixture to be used in the first step are not particularly limited. However, in view of efficient provision of a high-activity crystalline MWW-type titanosilicate catalyst for providing an oxidized compound, each of the above-mentioned ranges is preferred. An element other than the elements described above can also be present together in the mixture to be used in the first step. However, if an alkali metal or an alkaline earth metal is present in a somewhat large amount, titanium may be prevented from entering into the framework. Therefore, the amount of an alkali metal or an alkaline earth metal may preferably be smaller. More specifically, for example, the total moles of an alkali metal and an alkaline earth metal may preferably be smaller than the moles of titanium. The total moles of an alkali metal and an alkaline earth metal may preferably be {fraction (1/10)} times or less the moles of titanium, more preferably {fraction (1/100)} times or less the moles of titanium.
The heating temperature to be used in the first step is not particularly limited. However, in the case of synthesizing a precursor, the heating may preferably be performed under hydrothermal reaction conditions. The term xe2x80x9chydrothermal reactionxe2x80x9d as used herein means, as described in Hyojun Kagaku Yogo Jiten (Standard Chemical Glossary), Item xe2x80x9cHydrothermal Reactionxe2x80x9d, edited by the Chemical Society of Japan, published by Maruzen (Mar. 30, 1991), a synthesis or a modification reaction of a substance to be performed in the presence of water at high temperature, particularly to be performed in the presence of water at high temperature and high pressure. A synthesis reaction utilizing the hydrothermal reaction is called xe2x80x9chydrothermal synthesisxe2x80x9d. Therefore, in the first step, the heating may preferably be performed under hydrothermal synthesis conditions such that a mixture comprising a template compound, a titanium-containing compound, a boron-containing compound, a silicon-containing compound and water is charged into a closed container such as autoclave and is pressurized under heating. The heating temperature may preferably be in the range of from 110 to 200xc2x0 C., more preferably from 120 to 190xc2x0 C.
If the temperature in the hydrothermal synthesis is below this range, the intended product may not be obtained, or even if obtained, the heating may take a long period of time, and such a procedure is not suitable for a practical purpose. On the other hand, if the temperature exceeds this range, the yield of the intended product is disadvantageously decreased in the oxidation reaction using the resultant catalyst which is finally been obtained in this manner.
The hydrothermal synthesis may usually be performed for 2 hours to 30 days, preferably for 3 hours to 10 days. If the hydrothermal synthesis time is less than this range, the crystallization can be insufficient so that a high-performance catalyst may not be obtained. On the other hand, even if the hydrothermal synthesis is performed for a time period exceeding this range, the resultant catalytic activity is not substantially enhanced. In this case, an adverse effect such as conversion of the materials into another phase or an increase in the particle size can be caused disadvantageously.
Next, the second step is described below. The second step is a step of calcining the precursor obtained in the first step, to thereby obtain a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound.
The method of calcining the precursor is not particularly limited and may be performed under known conditions in the usual calcination of a catalyst. The calcination may be performed in the closed system or in the flow system, and if desired, the calcination may be performed in an inert gas stream, such as nitrogen gas stream. The calcination temperature may preferably be in the range of from 200 to 700xc2x0 C., more preferably from 300 to 650xc2x0 C., particularly preferably from 400 to 600xc2x0 C. If the calcination temperature is less than 200xc2x0 C., the template compound may not be satisfactorily removed. On the other hand, if the calcination temperature exceeds 700xc2x0 C., the MWW-type crystal structure may be destroyed, and as a result, this destruction may adversely affect the resultant catalytic performance.
The process for producing a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound according to the present invention in the third aspect is described in detail below. The process for producing a catalyst according to the present invention in the third aspect is a process of converting a titanosilicate in an amorphous state into a precursor having a lamella phase called MCM-22(P) by using piperidine or hexamethyleneimine as a template, and using boron (boric acid) as a structure supporting agent (first step); and then calcining the precursor (second step), to thereby obtain a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound.
There is described a more specific embodiment of the process for producing a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound. For example, an aqueous solution of piperidine or hexamethyleneimine (template) is divided into two portions, tetraalkyl orthotitanate is added to one of the two portions and dissolved therein, a boron compound is added to the other of the two portions and dissolved therein, and silica is further added to each of the two portions, and then the resultant mixture are stirred, to prepare two kinds of homogenous gels containing titanium or boron.
These two kinds of gels are mixed with each other and thoroughly stirred, and thereafter the mixture is transferred to a closed container such as autoclave and subjected to a hydrothermal synthesis. The thus obtained solid product is separated from the mother liquor by filtration or the like, thoroughly washed with water and then dried. By calcining the thus obtained precursor, a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound can be obtained.
The catalyst which is obtainable by the production process according to the present invention in the third aspect may be used as a catalyst for an oxidation reaction as it is. The boron which has been introduced inside or outside the framework present in the titanosilicate obtained by this production process, or the anatase phase which has resulted from the condensation of titanium itself which does not participate in an oxidation reaction may be removed at least partially by contacting the catalyst with an acid. By the contact of the catalyst with the acid, the thus obtained crystalline MWW-type titanosilicate catalyst for providing an oxidized compound can have a higher performance.
A certain effect may be obtained, when the catalyst is contacted with an acid before or after the calcination, or both before and after the calcination in the process for producing a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound. However, a particularly enhanced effect can be obtained, when the catalyst in the precursor state is contacted with an acid before the calcination. In the latter case, the by-product anatase phase due to the calcination can be strongly suppressed.
The xe2x80x9ccontact with an acidxe2x80x9d as used herein specifically means an operation such that a solution containing an acid or an acid itself is contacted with the precursor which has been obtained after the first step, or with the titanosilicate which has been obtained after the second step. The contacting method is not particularly limited. The contacting method may be a method of spraying or applying an acid or an acid solution to the precursor or titanosilicate, or a method of dipping the precursor or titanosilicate in an acid or an acid solution. The method of dipping the precursor or titanosilicate in an acid or an acid solution is simple and easy, and therefore this method is preferred.
The acid to be used for the above-mentioned acid contact may be an inorganic acid, an organic acid or a salt of these acids. Specific examples of preferred inorganic acids may include hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid. Specific examples of preferred organic acids may include formic acid, acetic acid, propionic acid and tartaric acid. Examples of the salt of these acids may include sodium salt, potassium salt, calcium salt, magnesium salt and ammonium salt of these acids.
The contact with an acid may be performed either before or after the calcination as described above, but may preferably be performed before the calcination so as to attain an enhanced effect. A solid substance such as precursor is dipped in an acid solution in an amount of approximately from 5 to 100 ml per one gram of the solid substance, and kept therein for a predetermined time. Thereafter, the solid is recovered from the acid solution by filtration or the like, and then thoroughly washed with a solvent. Stirring is not always necessary but may be performed.
In the case of using the acid in the form of a solution, the solvent is not particularly limited. Specific examples thereof may include water, alcohols, ethers, esters and ketones. Among these, water is preferred.
The acid concentration is not particularly limited but may suitably be on the order of 0.1 to 10 mol/l. The temperature may be in the range of from 0 to 200xc2x0 C., but may preferably be from 50 to 180xc2x0 C., more preferably from 60 to 150xc2x0 C. The treatment time may be from 0.1 hour to 3 day, but may suitably be from 2 hours to 1 day.
The present invention in a fourth aspect is described below. The present invention in the fourth aspect is a process for producing an oxidized compound comprising: performing an oxidation reaction of a compound having a carbon-carbon double bond and at least one of other functional group wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent in the presence of the crystalline MWW-type titanosilicate catalyst for providing an oxidized compound according to the present invention in the first or second aspect. According to the production process for an oxidized compound according to the present invention in the fourth aspect, the oxidation reaction of a carbon-carbon double bond only can be selectively performed substantially without affecting other functional groups of the compound having a carbon-carbon double bond and at least one of other functional group. Needless to say, other functional groups may be simultaneously reacted, to thereby obtain an entirely different product. Such a case, of course, may be included in the scope of the present invention in the fourth aspect.
Specific examples of the peroxide which is usable in the present invention in the fourth aspect may include hydrogen peroxide and organic peroxides. Examples of the organic peroxide may include tert-butyl hydroperoxide, tert-amyl hydroperoxide, cumene hydroperoxide, ethylbenzene hydroperoxide, cyclohexyl hydroperoxide, methylcyclohexyl hydroperoxide, tetralin (i.e., tetrahydronaphtalene) hydroperoxide, isobutylbenzene hydroperoxide, ethylnaphthalene hydroperoxide and peracetic acid. However, the peroxides usable in the present invention are not limited to these specific compounds. These peroxides may also be used in combination of two or more species thereof.
The peroxide to be used for such a purpose may particularly preferably be hydrogen peroxide. An aqueous hydrogen peroxide solution having any of various concentrations may be used. Examples of such concentrations may include, e.g., 30 mass %, 60 mass %, 90 mass % or the like. The amount of peroxide to be added to the reactant is not particularly limited, and the amount may be equivalent or more to the carbon-carbon double bond of the compound having a carbon-carbon double bond and at least one of other functional group, which is a raw material to be subjected to an oxidation reaction, or the amount may be equivalent or less, depending on the conditions.
The compound having a carbon-carbon double bond and at least one of other functional group for use in the process for producing an oxidized compound according to the present invention in the fourth aspect is not particularly limited, and may be any compound as long as it has a carbon-carbon double bond and at least one other functional group within one molecule thereof. In this case, a compound containing two or more carbon-carbon double bonds, of course, may be included within the definition of the above xe2x80x9ccompound having a carbon-carbon double bond and at least one of other functional groupxe2x80x9d.
Specific examples of the other functional group may include an alkenyl group, an alkynyl group, an aryl group, an arene group, an alcohol group, a phenol group, an ether group, an epoxide group, a halogen group, an aldehyde group, a ketone group, a carbonyl group, an ester group, an amide group, a cyanate group, an isocyanate group, a thiocyanate group, an amine group, a diazo group, a nitro group, a nitrile group, a nitroso group, a sulfide group, a sulfoxide group, a sulfone group, a thiol group, an orthoester group, a urea group and imine group. However, the xe2x80x9cother functional groupxe2x80x9d usable in the present invention is not limited to these specific compounds. Two or more of the same functional group may be contained in one molecule, and/or two or more kinds of functional groups may be contained in one molecule.
More specific examples of the compound having a carbon-carbon double bond and at least one other functional group may include allyl ethers, compounds having from 3 to 10 carbon atoms, ethers of polyhydric alcohol, and carboxylic acid esters. Of course, these compounds may also be used in combination of two or more species thereof.
More specifically, examples of the allyl ethers may include allyl methyl ether, allyl ethyl ether, allyl propyl ether, allyl butyl ether, allyl vinyl ether and diallyl ether.
Examples of the compounds having from 3 to 10 carbon atoms may include allyl alcohol, allyl bromide, allyl chloride, acrolein, methacrolein and acrylic acid.
Examples of the ethers of polyhydric alcohol may include ethylene glycol monoalkenyl ether, ethylene glycol dialkenyl ether, 1,2-propanediol monoalkenyl ether, 1,2-propanediol dialkenyl ether, 1,3-propanediol monoalkenyl ether, 1,3-propanediol dialkenyl ether, 1,2-butanediol monoalkenyl ether, 1,2-butanediol dialkenyl ether, 1,3-butanediol monoalkenyl ether, 1,3-butanediol dialkenyl ether, 1,4-butanediol monoalkenyl ether, 1,4-butanediol dialkenyl ether, and pentaerythritol monoalkenyl ether, pentaerythritol dialkenyl ether, pentaerythritol trialkenyl ether and pentaerythritol tetraalkenyl ether, trimethylolpropane monoalkenyl ether, trimethylolpropane dialkenyl ether, and trimethylolpropane trialkenyl ether.
Examples of the carboxyllic acid esters may include allyl formate, allyl acetate, allyl tartrate, allyl propionate and allyl methacrylate.
Examples of particularly preferred combination may include a combination such that the compound having a carbon-carbon double bond and at least one of other functional group is diallyl ether, allyl acetate, allyl methacrylate or allyl alcohol and the oxidizing agent is hydrogen peroxide.
The amount of the crystalline MWW-type titanosilicate catalyst for providing an oxidized compound used in the process for producing an oxidized compound according to the present invention in the fourth aspect is not particularly limited. The preferred range thereof may vary depending on the kind of oxidation reaction, the reaction temperature, the reactivity and temperature of the substrate or reactant, the concentration of peroxide, the kind and concentration of solvent, and the reaction form or type (e.g., batch system, continuous system). In a case where the catalyst is used in a slurry system, the amount of the catalyst may usually be in the range of from 0.1 to 20 mass %, more preferably from 0.5 to 10 mass %, in terms of the concentration of the catalyst in the reactant mixture. In the case of a fixed-bed flow reaction system, the apparent amount of the catalyst may preferably be larger than the above-mentioned range.
The shape or form of the crystalline MWW-type titanosilicate catalyst for providing an oxidized compound is not particularly limited. The form may be a powder, microspheres, pellets or extrusion-molded articles, or the catalyst may also be in a form such that it is supported on a support or carrier. In the molding of the catalyst, a binder may be used. The binder or support for such a purpose may preferably be a substance which is substantially non-acidic or weakly acidic, and which does not accelerate the decomposition reaction of the peroxide or the decomposition reaction of the intended oxidized compound.
The oxidation reaction in the process for producing an oxidized compound according to the present invention in the fourth aspect may be performed without using a solvent or in the presence of an appropriate solvent. Examples of the appropriate solvent may include alcohols, ketones, nitrites and water. Specific examples of alcohols may include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butanol, amyl alcohol, ethylene glycol, propylene glycol and 1,2-butanediol. Specific examples of ketones may include acetone, methyl ethyl ketone and diethyl ketone. Specific examples of nitrites may include acetonitrile, propionitrile and benzonitrile. These may be used singly or as a mixture thereof. Among these solvents, preferred are acetone, acetonitrile and water, and more preferred is acetonitrile.
In the process for producing an oxidized compound according to the present invention in the fourth aspect, the reaction temperature at the oxidation reaction, which is not particularly limited, may preferably be from 0 to 150xc2x0 C., more preferably from 10 to 100xc2x0 C. If the reaction temperature is less than 0xc2x0 C., the reaction rate is low and this temperature is not suitable for practical purposes. On the other hand, if the temperature exceeds 150xc2x0 C., a decomposition reaction of the peroxide may seriously proceed and, further, a decomposition reaction of the intended product may disadvantageously be accelerated.
The oxidation reaction is generally an exothermic reaction, and therefore, the heat of reaction may preferably be removed by a suitable method so as to control the reaction temperature to a constant range. The reaction pressure is not particularly limited.
The oxidation reaction in the process for producing an oxidized compound according to the present invention in the fourth aspect may be performed by any method in a batch system, a continuous system or a semi-continuous system, e.g., by using a suitable reactor or reaction apparatus such as fixed bed reactor, fludized-bed reactor, moving-bed reactor, tank reactor, stirring slurry-type reactor, continuous stirred tank reactor (CSTR). With respect to the mixture containing a crystalline MWW-type titanosilicate catalyst for providing an oxidized compound, a compound having a carbon-carbon double bond and at least one other functional group and a peroxide, these components constituting the mixture may be mixed partially or all at once or may be mixed in sequence or in order. It is also possible to mix the two species selected from the three species of these components (i.e., the catalyst, the compound having a carbon-carbon double bond and at least one of other functional group, and the peroxide), and then mix the remaining one species of these components into such a mixture.
In this reaction, the intended oxidized compound (reaction product) may be separated by a separation/purification method used in an ordinary purification procedure. More specifically, for example, when the reaction is performed in a batch system, when the amount of the oxidized compound which has been produced reaches a value in the desired region, the oxidized compound may be separated and recovered from the reaction mixture by using any known method such as fractional distillation, extract distillation or liquid-liquid extraction.
In the case of a slurry-type reactor, the crystalline MWW-type titanosilicate catalyst for providing an oxidized compound can be recovered by a suitable method such as filtration or centrifugation, and the thus recovered catalyst can be reused as a catalyst for oxidation reaction.
In the case of a fixed bed-type reactor, the crystalline MWW-type titanosilicate catalyst for providing an oxidized compound can be easily separated from the product (oxidized compound), the solvent, the unreacted compound having a carbon-carbon double bond and at least one of other functional group and the peroxide, while the catalyst remains being held in the reactor.
In the process for producing an oxidized compound according to the present invention in the fourth aspect, at least one of the recovered crystalline MWW-type titanosilicate catalyst for providing an oxidized compound, the unreacted compound having a carbon-carbon double bond and at least one of other functional group and the peroxide can be reused, after purification by an appropriate method or without purification thereof.
In the present invention in the fourth aspect, the recovered crystalline MWW-type titanosilicate catalyst for providing an oxidized compound generally has a tendency such that the activity thereof is decreased each time it is used repeatedly, and the catalyst after the repeated use cannot exhibit its initial activity. In such a case, the recovered catalyst may be regenerated or reproduced. The recovered catalyst may be regenerated by a conventionally known method. More specifically, the catalyst may be regenerated so that it has an initial activity, for example, by calcining the catalyst in air at a temperature of 100 to 600xc2x0 C.

Crystalline MWW-type titanosilicate catalyst for producing oxidized compound, production process for the catalyst, and process for producing oxidized compound by using the catalyst


An integrated circuit memory with improved di/dt control. The memory stores a plurality of data bits at intersections of word lines and bit line pairs. In response to a change in at least one of a plurality of address signals during a read cycle, first and second precharge signals are asserted, the second precharge signal asserted after the first precharge signal. An output buffer provides a data output signal at a voltage between a logic high and a logic low voltage in response to an assertion of the second precharge signal, and provides said data output signal corresponding to a voltage on an enabled bit line pair in response to a negation of the first precharge signal. Thus, the voltage on the data output signal changes less when the data bit is provided during the data period. The memory thus improves di/dt for a given access time, or conversely, allows reduced access time for a given di/dt.

As integrated circuit, there is generally a piece of silicon known as a die or chip which contains electrical circuit and which is connected to a lead frame. The chip has bonding pads which connected to the lead frame by tiny wires. The lead frame has leads which are used for connecting to a printed circuit board as part of a larger system. The leads of the lead frame have a certain amount of inductance as well ad capacitance and resistance. There is also some inductance in the wire from the bonding pad to the lead frame. The wire inductance, however, is significantly less than that of the lead frame. The connection of a lead of the lead frame to a circuit board also adds some inductance. As the switching speeds of integrated circuits have increased, this cumulative inductance has begun to have an impact on the performance of the integrated circuit.
Of course it is desirable to have integrated circuits which are very fast. The increased switching speed has also increased the rate at which current changes. This increased rate of current change causes a voltage drop across the inductance. The voltage across an inductance is equal to the inductance times the time rate of change of the current through that inductance. This is expressed as Ldi/dt, where L is the inductance and di/dt is the time rate of change of the current. As the di/dt becomes larger, the voltage across the inductance becomes larger. This voltage drop across an inductance causes a voltage differential between the lead location on the circuit board and the bonding pad to which it is connected on the integrated circuit. This can create a problem of having an internal supply at a different voltage than the voltage of a corresponding external supply. This problem can cause the internal supply voltages to differ by so much from their external levels that signals input to the chip are recognized incorrectly.
Conventional method of reducing di/dt focus on output buffers themselves. (See Wang, Karl L., et. al, "A 21-ns 32K.chi.8 CMOS Static RAM with a selectively Pumped p-Well Array, " IEE Journal of Solid-State Circuits, vol. SC-22, no. 5, October 1987; Wang, et al. in a U.S. patent application Ser. No. 07/348357 entitled "A Low di/dt Output Buffer with Improved Speed". ) In integrated circuit memories, there is a tradeoff between access time and di/dt. As access times are force down, new approaches must be found to reduce di/dt for a given access time.

Integrated circuit memory with improved di/dt control


A machine implemented method includes determining a signal modulation for each of a plurality of profiles; generating a first indicator indicating a signal modulation determined for a first profile in the plurality of profiles; generating a second indicator indicating a relationship between the signal modulation for the first profile and the signal modulation for each of the other profiles; notifying at least one node of the first and second indicators.

The MoCA 2.0 standard defines Modulation Profiles that have a set of parameters that determines the transmission between nodes, including preamble type, cyclic prefix length, modulations per subcarrier and transmit power. Each MoCA 2.0 Node maintains two PHY profiles for each 100 MHz unicast link: one for Nominal Packet Error Rate of 1e-6 (NPER) and one for Very Low Packet Error Rate of 1e-8 (VLPER). Similarly, two PHY profiles are maintained for 100 MHz Greatest Common Density (GCD) or Broadcast profiles: one for NPER (1e-6) and one for VLPER (1e-8). The GCD is a modulation format computed by a node for transmission to multiple recipient nodes. For the GCD or Broadcast format, the modulation used for each subcarrier is chosen to be the greatest possible modulation density that is less than or equal to the modulation density for that subcarrier as reported in the most recent Error Vector Magnitude (EVM) Probe Report the node sent to each of the other nodes. The EVM probe is used to determine the optimum modulation scheme for a set of subcarriers. During a new Node admission procedure, PHY profiles for both NPER and VLPER are distributed. Since the VLPER packets are more robust to errors than the NPER packets, the modulations per subcarrier of the VLPER profile are usually equal or lower than the corresponding modulations per subcarrier of the NPER profile.
However, the above-mentioned modulation schemes require a large amount of memory for each subcarrier. More specifically, 1,920 bits per modulation profile. Assuming 15 nodes, the total memory required for storing NPER and VLPER modulation profiles is 57,600 bits.
Accordingly, an apparatus and method to reduce modulation profile memory size may be desirable.

Device and method for reducing modulation profile memory size


An object of the present invention is that after return from fuel cut, an oxygen storage amount in a catalyst in an exhaust path and an oxygen storage amount in a catalyst in an exhaust gas recirculating path are promptly adjusted to be in appropriate states, respectively. A control apparatus for an internal combustion engine of the present invention controls the internal combustion engine including a recirculating gas generating cylinder and a recirculating gas nongenerating cylinder. The control apparatus includes: an exhaust gas recirculating path for connecting the exhaust path through which exhaust gas only in the recirculating gas generating cylinder is delivered and an intake system; a recirculating catalyst provided on the exhaust gas recirculating path; and rich control means that performs rich control for controlling an air-fuel ratio to be temporarily richer than a theoretical air-fuel ratio when fuel injection is restarted after return from the fuel cut. The rich control means includes air-fuel ratio control means that controls an air-fuel ratio in the recirculating gas generating cylinder to be richer than an air-fuel ratio in the recirculating gas nongenerating cylinder when the rich control and an exhaust gas recirculation by the exhaust gas recirculating path are simultaneously performed.

There has been widely known an internal combustion engine including an EGR path that connects an exhaust path and an intake path of the internal combustion engine for enabling exhaust gas recirculation (EGR) that recirculates a part of exhaust gas into the intake path via the EGR path (for example, see Patent Literature 1).

Control apparatus for internal combustion engine


A keyboard musical instrument learning aid having a plurality of keys including: sensing means operatively associated with the keyboard for sensing the presence of an object at a spaced disposition with respect to the keys of the keyboard; positioning means operatively associated with the sensing means for positioning the sensing means such that the spaced disposition is within a predetermined space with respect to the keys; and reporting means operatively associated with the sensing means and operable to report when an object is sensed to be present at the spaced disposition.

Students of piano are required to learn the correct position of the hands, fingers, wrist and forearm as one of the foundation skills in learning to play the piano. Similar foundation skills are a part of learning to play other keyboard musical instruments as well. One of the problems often encountered is that students may allow their wrists to drop too low. Sometimes, this can have a flow-on effect to poor posture and fatigue, and/or wrist or tendon strain. Another problem sometimes encountered is that students may overcompensate for having their wrists too low by raising their wrists to high. This can lead to poor finger control as well as the adverse effects on posture, fatigue and tendon strain.
In this specification, unless the context indicates otherwise, the term "learning aid" is to be taken to refer to a keyboard musical instrument learning aid and such term is to be taken to be synonymous with the term "keyboard musical instrument learning aid".
U.S. Pat. No. 7,714,220 to Sony Computer Entertainment discloses a learning aid for teaching hand placement on a variety of objects, including sporting equipment and such musical instruments as guitars, saxophones, woodwind and brass instruments (the Sony invention). However, the Sony invention is directed to the teaching of accurate placement of the fingers of the hands on the object. Moreover, the instruments towards which the Sony invention is directed are either fretboard, fingerboard or button-key instruments, and is not suited to aid the learning of the correct hand position for playing a keyboard instrument, the correct hand position being essentially the same for all positions of the fingers on the keys; that is, for the position of the fingers on all of the different keys.
The present invention aims to provide a keyboard musical instrument learning aid which alleviates problems associated with teaching and learning of correct hand position for playing keyboard musical instruments. Other aims and advantages of the invention may become apparent from the following description.

Keyboard musical instrument learning aid


Methods and apparatus to provide refresh when an out of range address is received are disclosed. An example method of providing a refresh signal to a memory cell includes receiving a memory address on address lines ranging from a most significant bit address line to a least significant bit address line. A memory driver logic device is coupled to the memory cell. An out of range logic decoder is coupled to provide a fixed logic input to a first input of the memory driver logic device. Address logic is provided to cause the memory driver logic device to enable the memory cell if the memory address is a local out of range address.

Asynchronous embedded static random access memory (SRAM) is a common memory device that requires refreshing of its memory cells to retain stored data. Embedded SRAM memory cells are typically composed of devices that hold data without having to refresh individual cells. However, the cells must have a complete electrical path to avoid a state that may cause loss of data integrity. Rather than refreshing on a periodic basis, which decreases the time during which a memory may be accessed, refreshes of the memory cells are typically performed only during a read operation during which the memory cells are read and a complete electrical path is maintained to enable the memory to retain the data.
A typical memory array includes eight word rows and multiple base two columns. The row is first selected and then the column is selected to cause the data from a particular memory cell to be addressed and refreshed by maintaining a complete electrical path. However, a circuit design using memory may not require an entire full base two range of columns or blocks or all the possible memory addresses in a row. Power conservation and gate efficiency is an important factor in circuit design and, thus, it is desirable to eliminate unnecessary memory capacity. For example, in the case of ASIC standard 2 port memory, users may configure the word length, bit length and x-y ratio by entering a desired memory length resulting in odd numbers of word lengths. When the addresses of words are not used, they are referenced as a global out of range in the case of an unused column address or a local out of range in the case of unused row addresses. For example, if a memory only requires 72 words, there would be nine full columns each having a four bit address, but seven potential block addresses would be not used and, thus, are possible global out of range addresses.
To read data from each cell, an address is sent to various row bit lines and column select lines that allow a particular word to be read. However, the cells must be refreshed during any read request because there is no scheduled refresh of the memory cells. In the case of a read directed to either a local or global out of bounds address (e.g., an attempt to access blocks 9-15 in the above example), the read would result in not refreshing the memory because the appropriate column would not exist, thereby breaking the complete electrical path and resulting in a bit line floating in a tristate condition and destroying stored data.
Thus, to insure that the memory array is refreshed whenever an out of range address is received the words in an existing row or column must be addressed to refresh the memory. The logic to determine the out of range address and refresh the appropriate existing memory blocks requires additional gates (e.g., out of range detection logic) and increases power consumption. In certain cases, access time to the memory is also increased because of the complexity of the out of range detection logic. Further, drive conflicts may occur because of propagation delay causing interference with subsequent read requests.

Methods and apparatus to provide refresh for global out of range read requests


Detection of a state of an oral appliance (such as an aligner, palatal expander, mandibular repositioning device, etc.) to determine if the oral appliance is functioning properly and/or if it has developed a defect.

Orthodontic procedures typically involve repositioning a patient's teeth to a desired arrangement in order to correct malocclusions and/or improve aesthetics. To achieve these objectives, orthodontic appliances such as braces, shell aligners, and the like can be applied to the patient's teeth by an orthodontic practitioner. The appliance can be configured to exert force on one or more teeth in order to effect desired tooth movements according to a treatment plan.
During orthodontic treatment with patient-removable appliances, the appliance may not function correctly due to a defect, or may develop a defect during use. In some instances, the appliance may be improperly installed, formed, or operated by the practitioner. There is a need for methods and apparatuses that allow monitoring of a state of the intraoral appliances. Described herein are methods and apparatuses for performing such monitoring.


A radiolucent orthopedic chuck includes a housing having a driver stem protruding from the top surface and a drill bit protruding from the underside in radially spaced relation from the driver stem so as to displace a drill secured to the driver stem from the axis of the drill bit so that fluoroscopy may be used to ensure accurate alignment of the drill bit with a hole of an intramedullary nail both prior to and during its operation. A drive train interconnects the driver stem and drill bit for rotation in unison. All parts of the chuck but for the drill bit preferably radiolucent.

The present invention is directed generally to a radiolucent orthopedic drill chuck which displaces the drill bit sufficiently away from the orthopedic drill that x-rays may be directed axially of the bit without interference by the drill for prompt and precise alignment and drilling.
Although the critical applications for the present invention are diverse, its conception and prototypic clinical trials have involved intramedullary nails. In this country alone, annual tibia surgeries include approximately twenty-three thousand closed reductions and one hundred eleven thousand open reductions. Femur fractures result annually in approximately thirty-three thousand closed reductions and one hundred thirty-one thousand open reductions. For femur fractures, an elongated intramedullary nail is inserted through the center of the bone from an incision in the hip whereupon the nail is stabilized by a single screw inserted through the bone and nail at an angle to the axis of the nail. It has long been a problem to then accurately drill holes aligned with the holes at the distal end of the nail for the interlocking screws.
The current techniques include various free hand techniques as well as techniques using various stationary metal devices. Whereas a fluoroscope is used to assist with proper positioning of the drill, all of these techniques have in common the necessity for removing the fluoroscopic image while drilling. The problem inherent with all of these techniques therefore is that they in fact require blind drillings.
In one manual technique, a large incision is made near the distal end of the nail to expose the bone. The surgeon manipulates an awl to mark the drilling site on the bone with the aid of a fluoroscopic screen. The surgeon gets radiated while positioning the awl. The awl is then set by pounding it against the bone. Alternately, the holes may be drilled percutaneously by positioning the awl to mark the skin, after which the awl is removed and a drill is directed toward the bone through the marked spot on the skin. In either event, the double step of first marking the drilling location with an awl and then moving the awl and inserting a drill increases the chances for error over and above the inherent difficulty of blind drilling.
Certain of the positioning devices afford six degrees of freedom of movement but these require much education on the techniques of using the machine and still result in blind drilling.
Olerud, et al., U.S. Pat. No. 4,625,718 discloses an aiming apparatus for a wire drill. Whereas this devise enables live action sighting, it has several shortcomings which are believed to be resolved by the present invention. First, the Olerud apparatus is awkward for a surgeon to use since it has two handles on both sides of the fluoroscopic beam. Since the head of the x-ray machine is generally positioned about ten inches from the drilling site, it is awkward to reach in and manipulate both handles simultaneously. It requires the drill to be positioned at a right angle to its normal drilling position so that the drill is pushed sideways in an unfamiliar manner during use. Secondly, the metal around the opening of the Olerud, et al., device is radio opaque which is a big disadvantage for sighting. Finally, the Olerud device rotates a wire, not the actual drill bit. Since wire burns bone, it is not a good idea to drill bone with it. Furthermore, since the diameter of the wire is much smaller than a drill bit, it is very difficult to accurately center the wire within the larger diameter nail openings. If the wire opening is eccentrically positioned, a hollow drill bit following the wire will strike the nail rather than be directed through the distal hole as intended.
Accordingly, a primary object of the invention is to provide a radiolucent orthopedic drill chuck which displaces the drill bit from the radio opaque drill for live sighting of the drill bit during the operation.
Another object is to provide a radiolucent orthopedic chuck which protects the surgeon's hand from exposure to the fluoroscopic sighting beam.
Another object is to provide a radiolucent orthopedic chuck which is lightweight, simple in construction and readily usable without special instruction.
Another object is to provide a radiolucent orthopedic chuck which enables the drilling of a hole for an interlocking screw to be quickly and accurately performed thereby reducing trauma to the patient and x-ray exposure of the surgeon.
Another object is to provide a radiolucent orthopedic chuck which is substantially entirely radiolucent but for the drilling bit to afford optimum sighting in use.
Another object is to provide a radiolucent orthopedic chuck which is simple and rugged in construction, economical to manufacture and efficient in operation.


Power monitoring circuitry is provided to monitor an input system power profile of processing tasks executing on a processing platform. An input is provided to receive from the processing platform, a processing system signal indicating a power being consumed by the processing platform. A counter is provided to store a count value corresponding to an accumulated number or amount of times that a warning threshold condition associated with a warning threshold value is satisfied by the received processing system signal in a count-accumulation time interval. The count value is supplied to a power control circuit of the processing platform via a bus in response to a read request from the power control circuit, the power control circuit being responsive to the count value to control a performance level of the processing platform.

Processors have dynamically changing power requirements depending on processing application demands. A number of different performance states of a processor may be implemented, for example, by selecting a processor frequency and a corresponding processor core voltage Vcc. Processor power=Vcc*K+leakage, where K is a relative constant based on processor frequency and capacitance. Leakage is approximately a constant corresponding to power wasted as a result of applying a voltage to a transistor. Thus the processor frequency and Vcc may be increased when processing workload is high to run faster and resulting in increased power consumption, whilst processor frequency and Vcc may be reduced when the processor is has a low workload or is idle to reduce processor consumption. The processor performance level may be set based on both processing workload and a maximum capacity of a corresponding power supply.
A power control unit of a processing platform may receive information from one or more sensors of the processing platform to sense variations in factors affecting performance of the processing platform such as operating frequency, operating current, operating voltage, battery charge levels etc. The power control unit may control at least one of a voltage regulator, a power source and one or more components of the processing platform to modify their operations to control processing performance.
Tolerance of a processing platform to sudden increases in processing loads (i.e. transients) is desirable because the sudden increase in workload can result in a momentary drop in voltage below a desired constant level (so called "voltage droop"). On the contrary, when the peak in processing workload falls, the system voltage may exhibit a peak in the voltage level. If the system voltage drops too low, such as below a minimum system voltage, as a result of power transients there may be a risk of inadvertent system shutdown (i.e. system crash). Processing platforms may be arranged to have a tolerance to power transients by providing sufficient headroom between: (i) a determined maximum power capacity of an available power supply; and (ii) a target processing platform performance level that the power control unit is permitted to set.
System power may be monitored by the processing platform polling data telemetry registers of the power supply or of one or more associated voltage regulators. For example, to monitor system power, the power control unit of the processing platform may poll registers of a voltage regulator via a bus such as a Serial Voltage Identifier (SVID) bus. There is likely to be limited bandwidth on the bus, which means that low sampling rates (for example, 100 μs) tend to be used. At the available low sampling rates it is unlikely to be possible to distinguish between two scenarios of equivalent average power:
1) "Constant Workload" where the SoC or other processing platform continually draws the average power; and
(2) "Bursty Workload" where the SoC or other processing platform intermittently draw very high power bursts, significantly exceeding the average with the remaining time below average power.
As a consequence, to safeguard against system crash, the processing performance level of the processing platform is set by the power controller to accommodate the worst case, that is, the bursty workload. This means that the available maximum power capacity of the power supply is not fully utilized to boost processing performance during periods when the workload is more constant. Thus potential processing performance gain derivable from a power supply can be lost as a result of the known ways of safeguarding against system crash.

Power monitoring for a processing platform


A threaded connection comprising a pin member formed on an end of a first tubular member. The pin member includes an inner seal pin portion, a threaded pin portion, and an outer seal pin portion. The inner seal pin portion has an inner diameter that is greater than an inner diameter of the outer seal pin portion. A box member is formed on an end of a second tubular member. The box member includes an inner seal box portion, a threaded box portion, and an outer seal box portion. The inner seal box portion has an outer diameter that is greater than an outer diameter of the outer seal box portion. The inner seal pin portion sealingly engages the inner seal box portion and the outer seal pin portion sealingly engages the outer seal box portion when the threaded pin portion is engaged with the threaded box portion.

This disclosure relates generally to methods and apparatus for coupling wellbore tubulars with a threaded connection that can be radially expanded. More specifically, this disclosure relates to methods and apparatus for providing an expandable threaded connection with a metal-to-metal seal.
During hydrocarbon exploration, a wellbore typically traverses a number of zones within a subterranean formation. Wellbore casings are then formed in the wellbore by radially expanding and plastically deforming tubular members that are coupled to one another by threaded connections. Existing apparatus and methods for radially expanding and plastically deforming tubular members coupled to one another by threaded connections may not be suitable for all wellbore environments.
For example, many expandable threaded connections rely on elastomeric materials to provide a seal. Elastomeric seals may not be suitable for certain high temperature environments on when exposed to certain wellbore fluids. In conditions where elastomeric seals may not be desirable, it may be preferable to have a threaded connection that utilizes a metal-to-metal seal. A connection that utilizes a metal-to-metal seal forms a seal between two abutting surfaces of the threaded connections that contact with sufficient compressive force to form a seal between the surfaces.
Although there are many available examples of threaded connections that utilize metal-to-metal seals, those threaded connections that are also rated for radial expansion have not proven suitable for all applications. Thus, there is a continuing need in the art for methods and apparatus for providing an expandable threaded connection with a metal-to-metal seal.

Expandable metal-to-metal seal connection


Systems and methods described herein concern improving an interior design of a vehicle under development. One embodiment presents an electronic survey to ridesharing customers from a plurality of ridesharing trips in a rideshare vehicle having a reconfigurable interior that is configured in accordance with a proposed interior design for the vehicle under development, the electronic survey pertaining to one or more features of the proposed interior design, and collects and stores, in a computer memory, responses to the electronic survey for the plurality of ridesharing trips. The proposed interior design is modified based, at least in part, on the responses to the electronic survey.

An important aspect of manufacturing a vehicle is the design of its interior. Features such as the design of the seats and their placement and configuration, legroom, headroom, instrument panels, electronic systems such as audio and video systems, and various user interfaces for vehicle systems can have a significant impact on a consumer's ultimate satisfaction with a vehicle. Particularly for popular vehicle models, manufacturers may want to ensure that a new interior design will be accepted by consumers before the design for a new model year is mass-produced. Gauging consumer acceptance in advance can sometimes be difficult and expensive, especially if market testing involves iteratively modifying prototype vehicles to correct weaknesses in the proposed interior design.

Methods and systems for improving an interior design of a vehicle under development

Toyota Motor Engineering & Manufacturing North America, Inc.


A first motor controller generates commanded speeds of a first rotor of a first electric motor for a first time interval and a second time interval. A first speed monitor detects observed speeds of the first rotor for the time intervals. A first ratio is determined based on a relationship between respective commanded speeds and corresponding observed speeds for the first time interval and the second time interval. A first data processor increments a persistence counter for the first motor if the first ratio increases or changes during the time intervals. A first motor deceleration is estimated if the persistence counter exceeds a stall limit count. A target rotor speed of a second motor is adjusted based on the estimated first motor rate of change to track the first motor rate of change (or first rotor speed) if the persistence counter exceeds the stall limit count.

In certain prior art, multiple electric motors may be used to drive blades of a common assembly, such as a mower deck of a mower or a cutter. If the motors are presented with different loads, the more heavily loaded motor may perform inadequately or may reduce longevity because of thermal stress or mechanical stress. Accordingly, there is need for a method and system for controlling electric motors of a common assembly to enhance performance of one or both motors or to reduce the thermal or mechanical stress on one or both motors, for example.

Method and system for controlling electric motors of a common assembly


A method for calculation of at least one software usage metric is disclosed, the software usage metric describing a plurality of software products installed in a computing infrastructure including a plurality of computing machines organized into a plurality of computing groups. The method includes installing a first set of software products in each computing machine in a first computing group of a plurality of computing groups, scanning one computing machine in the first computing group to discover that the first set of software products are installed thereon; and calculating an overall usage metric for the first computing group based on a number of computing machines belonging to the first computing group and the discovered first set of software products.

The present disclosure relates to the field of digital computer systems, and more specifically, to the calculation of software usage metrics.
Large companies are often divided into many business units, and each business unit can have internal organizations, such as human resources (HR) or information technology (IT). Despite the business units being different, some of the organizations therein, such as HR and IT, may be similar to one another across the business units. Each of the business units, including the organizations, can be allocated numerous computing machines that include software products that are selected from predefined lists of forbidden and allowed software products, depending on the requirements of the business units and/or organization.

International Business Machines Corporation


An apparatus is used to pull a single crystal, wherein a flow of an inert gas to the single crystal to be grown, a pressure in an apparatus body, and a temperature environment are always kept constant by keeping a melt level at a prescribed position in spite of changes in volume of a quartz crucible between batches and thermal deformation of the quartz crucible, so that high quality single crystals can be pulled. The apparatus has a reference reflector arranged inside an apparatus body, a level position measuring unit to measure an actual level position by detecting a mirror image position of the reference reflector reflected in the melt surface using a one-dimensional CCD camera arranged outside the apparatus body, a crucible ascent speed adjustment value calculating unit to calculate an adjustment value of the crucible ascent speed based on an output from the level position measuring unit, an adjustment value adding unit to add the adjustment value to the crucible ascent speed, and a level position controlling unit to control the level position in the crucible by controlling a motor for crucible lifting based on an output from the adjustment value adding means to control the crucible ascent speed.

1. Field of the Invention
The present invention relates to an apparatus for pulling a single crystal and, more particularly, to an apparatus for pulling a single crystal used for pulling a single crystal of silicon or the like from a melt of a material for forming a crystal by a pulling method such as the Czochralski method (hereinafter, referred to as the CZ method).
2. Description of the Relevant Art
At present, the majority of silicon single crystals used for manufacturing a substrate for forming a circuit component of a LSI (large scale integrated circuit) and the like have been pulled by the CZ method. FIG. 3 is a diagrammatic sectional view of a conventional apparatus for pulling a single crystal used for the CZ method, and in the Figure, reference numeral 21 represents a crucible.
The crucible 21 comprises a bottomed cylindrical quartz crucible 21a and a bottomed cylindrical graphite crucible 21b fitted on the outer side of the quartz crucible 21a. The crucible 21 is supported with a support shaft 28 which rotates in the direction shown by the arrow A in the Figure at a prescribed speed. A heater 22 of a resistance heating type and a heat insulating mold 27 arranged around the heater 22 are concentrically arranged around the crucible 21. The crucible 21 is charged with a melt 23 of a material for forming a crystal which is melted by the heater 22. On the central axis of the crucible 21, a pulling shaft 24 made of a pulling rod or wire is suspended, and at the front thereof, a seed crystal 35 is held by a holder 24a. These members are arranged within a water cooled type apparatus body 29 wherein pressure can be controlled.
A window 29a is formed in the middle portion in the height direction of the apparatus body 29. Above the window 29a in a slanting direction, a one-dimensional CCD camera 11 is arranged in such a position that a single crystal 36 during pulling can be seen through the window 29a, and the one-dimensional CCD camera 11 is connected to a diameter measuring means 8 of the single crystal 36. The diameter measuring means 8 is connected to a crucible ascent speed calculating means 9, which captures an input value of the pulled single crystal 36 from the diameter measuring means 8 and information on the pulled length from a pulling means 5 of the pulling shaft 24 to calculate a decrease in volume of the melt within the crucible 21, so as to calculate an ascent speed of the crucible 21 based on the decrease in the melt volume.
A method for pulling a single crystal 36 using the above apparatus for pulling a single crystal is described with reference to FIGS. 3 and 4(a)-(d). FIGS. 4(a)-4(d) are partial enlarged front views diagrammatically showing a seed crystal and the vicinity thereof in part of the steps in pulling a single crystal.
Although it is not shown in FIGS. 4(a)-(d), the pressure within the apparatus body 29 is reduced, and an inert gas is introduced into the apparatus body 29 so as to make an inert gas atmosphere under reduced pressure therein. Then, the material for forming a crystal is melted by the heater 22 and is maintained for a period of time so as to sufficiently release gas contained in the melt 23. While the pulling shaft 24 is rotated on the same axis in the reverse direction of the support shaft 28 at a prescribed speed, the seed crystal 35 held by the holder 24a is caused to descend and is brought into contact with the melt 23. After the front portion of the seed crystal 35 is partially melted into the melt 23, the single crystal 36 begins to be pulled from the melt (the seeding step) (FIG. 4(a)).
In making a crystal grow at the front of the seed crystal 35, the pulling shaft 24 is pulled at a higher speed than the below-described formation speed of a main body 36c, and the crystal is narrowed to have a prescribed diameter, leading to the formation of a neck 36a (the necking step) (FIG. 4(b)). By slowing down the pulling speed of the pulling shaft 24 (hereinafter, simply referred to as the pulling speed), the neck 36a is made to grow to have a prescribed diameter, leading to the formation of a shoulder 36b (the shoulder formation step) (FIG. 4(c)). By pulling the pulling shaft 24 at a fixed rate, the main body 36c having a uniform diameter and a prescribed length is formed (the main body formation step) (FIG. 4(d)).
Furthermore, although it is not shown in FIG. 4, in order to prevent induction of high density dislocation to the single crystal 36 by a steep temperature gradient at the end, the diameter of the single crystal 36 is gradually decreased and the temperature of the whole single crystal 36 is gradually lowered, leading to the formation of an end-cone. Then, the single crystal 36 is separated from the melt 23. After the above steps, cooling the single crystal 36 leads to the completion of pulling the single crystal 36.
In pulling the single crystal 36, in order to obtain a good quality single crystal 36, it is necessary to drive the support shaft 28 using a motor 10 for crucible elevating to move up the crucible 21 up to control the position of the crucible 21 so that the melt surface is always kept in a fixed position with respect to the heater 22. In the crucible ascent control, a method wherein the amount of ascent of the crucible 21 is calculated by calculating a decrease in volume of the melt 23 from the volume of the pulled single crystal 36 has been generally used. Since the amount of ascent of the crucible 21 is calculated by calculating the decrease in volume of the melt 23 from the volume of the pulled single crystal 36 in the above crucible ascent control, the accurate volume of the pulled single crystal 36 needs to be obtained. In addition, in order to calculate the accurate amount of the crucible ascent from the decrease in volume of the melt 23, the accurate internal diameter of the crucible is required. However, in actual pulls, errors are introduced to the crucible ascent control by errors in measuring crystal weight and crystal diameters, changes in the internal diameter of the quartz crucible 21a due to softening thereof during pulling, and changes in the internal diameter of the quartz crucible 21a between batches originating in variations in manufacturing the quartz crucible 21a. Therefore, it is necessary to actually measure to control the level position during pulling the single crystal 36.
In order to solve the above problems, a method for measuring the level position has been disclosed in Japanese Kokai No. 63-281022. In the method for measuring the level position, the level position is calculated from the position of the mirror image of a radiation screen reflected in the melt surface. The method makes it possible to measure the level position during crystal pulling. Similar to the method disclosed in the above publication, a method wherein the level position is controlled based on the mirror image position of a radiation screen reflected in the melt surface has been disclosed in Japanese Kokai No. 07-277879. In the method, by moving a crucible up and down so that the mirror image position of the radiation screen is kept fixed, the level position is controlled so as to be kept fixed.
However, in these methods, the inclination of the melt surface in which the mirror image of the radiation screen is reflected causes a change of the mirror image position even when the level position does not actually change, leading to the erroneous recognition and control of the level position. Factors of the inclination of the melt surface are changes in crystal diameter and changes in crucible rotational speed. Therefore, errors arise with changes in crystal diameter and changes in crucible rotational speed when the level position is controlled based on only the mirror image position of the radiation screen.
Particularly, the shoulder formation step wherein the crystal diameter is increased to a desired diameter from the seed crystal is a problem. In the shoulder formation step, the inclination of the melt surface increases with an increase in crystal diameter. Therefore, when the level position control by which the mirror image position of the radiation screen is kept fixed is conducted in the shoulder formation step, the actual level positions before and after the shoulder formation step become different.
The same errors are also caused by changes in crystal diameter in the main body formation step. In addition, when the level position control is conducted based on only the mirror image position of the radiation screen on the melt surface, the occurrence of irregularity in measuring the level position makes it impossible to carry out the ascent/descent control of the crucible 21.


Control techniques are disclosed for devices that are members of ad hoc rendering networks. A first network device may receive a data record representing state of the network. The data record may contain data identifying device(s) that are members of the network, any grouping(s) of the device(s) defined for the network, and a play state of the device(s). When the first network device receives the data record, it may store the data record locally at the first player device. The first player device may determine whether the data record possesses a command altering a play state of a device. If so and if the command is addressed to the first player device, the first player device may execute the command at the first player device. The data record may be relayed among all devices in the ad hoc rendering network, and each device may perform this same process. In this manner, state updates propagate to all devices that are members of the rendering network, and all such devices store state data of all other devices.

The present disclosure relates to formation and management of ad hoc networks of playback devices in media rendering applications.
A variety of modern consumer electronic devices have been developed for rendering of digital media assets. High definition televisions and smart speaker devices perhaps are the most intuitive examples, and they provide opportunities to render media assets from a variety of sources. Consumers no longer are required to purchase individual media devices such as optical discs on which the media asset it encoded. Instead, it has become common for the devices to download media assets from online sources such as the Internet and render them.
It remains a challenge to manage playback and rendering events in a synchronized manner. While a consumer finds it fairly simple to download an audio/visual asset for display on a single device, it becomes much more challenging to render a video component on a first device, and render separate audio elements of the asset (say, left and right channels of audio) on other devices.

This patent is subject to a terminal disclaimer.

Management of devices in ad hoc rendering networks


A drilling tool (10) of the displacing type comprises a displacing head (22) including a cylindrical mid head portion (24) and lower and upper frustoconical head portions (26, 28). A lower drill portion (12) carries a helical rib (16) which also extends over the lower head portion (26), all portions of this rib being of equal height. The upper head portion (28) is formed with spiroconical displacing walls (32).

Such a drilling tool is disclosed in the GB 2 132 667 A1 document. This drilling tool has a displacing head formed with smooth exactlie frustoconical lower and upper portions. Due to the large surface contact between the displacing head and the soil large forces are required to rotate and advance the drilling tool.
The object of the present invention is to improve a drilling tool of the displacement type so such that the drive unit acting on the drilling tool needs to provide smaller forces in at least one of the two feed directions (circumferential direction, axial direction).

DELMAT Maschinenfabrik Reihnold Dornfeld GmbH