A shaft member for a fluid dynamic bearing device that has a recess to cause a dynamic pressure effect of a fluid in a bearing clearance, which is formed on it by rolling, and where a surface layer portion of the recess and a surface layer portion of a surrounding region of the recess has a nitride layer, and where nitrogen is diffused and penetrated in a material of the shaft member that is formed by nitriding after the rolling.

A fluid dynamic bearing device relatively rotatably supports a shaft member by a dynamic pressure effect of a fluid caused in a bearing clearance. Recently, by taking advantage of its excellent rotational accuracy, high-speed rotation property, quietness, and the like, the fluid dynamic bearing device is suitably used as a bearing device for a motor to be mounted to various electrical apparatuses such as information equipment. Specifically, the fluid dynamic bearing device is used as a bearing device for a spindle motor mounted on information equipment including magnetic disk devices such as HDD, optical disk devices such as CD-ROM, CD-R/RW, and DVD-ROM/RAM, and magneto-optical disk devices such as MD and MO, and as a bearing device for motors such as a polygon scanner motor for a laser beam printer (LBP), a color wheel motor for a projector, or a fan motor.
For example, as a fluid dynamic bearing device incorporated into the spindle motor for an HDD, there is known one having a structure in which both a radial bearing portion for supporting the shaft member in a radial direction and a thrust bearing portion for supporting the shaft member in a thrust direction are structured by a dynamic pressure bearing. In this case, in one of an inner peripheral surface of a bearing sleeve and an outer peripheral surface of a shaft member opposed thereto, a dynamic pressure groove serving as a dynamic pressure generation portion is formed, and a radial bearing portion is often formed in a radial bearing clearance therebetween. Further, in one of a one end surface of a flange portion provided to the shaft member and an end surface of the bearing sleeve opposed thereto, the dynamic pressure groove is formed, and a thrust bearing portion is often formed in a thrust bearing clearance therebetween (for example, see Patent Document 1: JP 2003-239951 A).
The dynamic pressure groove is formed, for example, in a herringbone shape or a spiral shape, or a multi-arc or step-like arrangement in an outer peripheral surface of the shaft member. As methods of forming the dynamic pressure groove of this type, there are known, for example, cutting (see, for example, Patent Document 2: JP 08-196056 A) and etching (see, for example, Patent Document 3 JP 06-158357 A).
Further, as a method of forming the dynamic pressure groove, which enables reduction in material cost and machining cost compared to the cutting and etching, there is known rolling, for example. In this case, by applying predetermined heating after the rolling, a surface hardness of the material is often increased (see, for example, Patent Document 4 JP 07-114766 A).

Shaft member for fluid dynamic bearing device


A method for enabling multiple functions to be performed by a first mobile device during a video conference within a mobile device environment includes: performing a second function at a first mobile device while a first function is being performed at the first mobile device without interruption of the first function, wherein the first function is a video conference between a first entity associated with the first mobile device and a second entity associated with a second mobile device, and wherein the first function and the second function are different functions.

Modern technology provides for a variety of communication means and methods. For example, there are many types of communications including voice calls, video calls, text messages, photo messages, etc. Additionally, communication may be one-to-one or multi-party communications. Typically multi-party communications are accomplished by a plurality of devices communicating with a central infrastructure. For example, a central infrastructure may be a central computer server or a group of computer servers maintained in a server farm. A central infrastructure may be expensive to establish, maintain and operate.
Many advances have been made in mobile handheld technology. Specifically smart phones have increasingly more features. There is an increased demand to develop the functionality of the smart phones and their components. For example, some smart phones now have two cameras, one mounted on the front and one on the back. Additionally, smart phones may have more than one method of connecting to a network to transmit data. These features can be used to provide a more comprehensive communication experience.
Advances have also been made with respect to video conferencing between mobile devices. For example, Google Hangout™ enables people to share photos and have real-life conversations. However, when switching from one function to another function, such as video conferencing to an audio call or texting, the video picture of the video conference will disappear to account for the second function (e.g., the audio call). In another example Cisco WebX™ enables online meeting experiences by incorporating audio, video and real-time content sharing. Thus, Cisco WebX™ allows for a group of people to switch between at least two modalities (e.g., audio, video, etc.). However, these functions and modalities are not available to non-participants to the online meeting. Thus, many limitations exist with regard to performing multiple functions while video conferencing.
The drawings referred to in this description of embodiments should be understood as not being drawn to scale except if specifically noted.

Performing multiple functions by a mobile device during a video conference


An electronic device may be provided with wireless circuitry. An application processor may generate wireless data that is to be transmitted using the wireless circuitry and may process wireless data that has been received using the wireless circuitry. The wireless circuitry may include multiple baseband processors, multiple associated radios, and front-end module and antenna circuitry. Sensors may be used to provide the application processor with sensor data. During operation, the application processor and the baseband processors may be used to transmit and receive wireless communications traffic. A multiradio controller integrated circuit that does not transmit or receive the wireless communications traffic may be used in controlling the wireless circuitry based on impedance measurements, sensor data, and other information.

This relates generally to electronic devices and, more particularly, to electronic devices with wireless communications circuitry.
Electronic devices often include wireless communications circuitry. For example, cellular telephones, computers, and other devices often contain antennas and wireless transceivers for supporting wireless communications.
It can be challenging to ensure that wireless communications circuitry in an electronic device will perform satisfactorily in all operating conditions. For example, the operating environment of an electronic device may affect antenna performance or the simultaneous use of two different communications bands within a device may give rise to a potential for interference.
These potential performance issues can be exacerbated in certain wireless communications circuit architectures. In some devices, multiple baseband processors are used each of which handles a different type of wireless communications. The operation of these different baseband processors and other wireless circuits may often be poorly coordinated. This can give rise to conflicts. For example, wireless performance may suffer if a cellular telephone baseband processor is being used to transmit and receive cellular telephone traffic while a wireless local area network baseband processor is being used to transmit and receive wireless local area network traffic. Unless care is taken, the wireless performance of an electronic device may not be satisfactory under certain operating conditions.
It would therefore be desirable to be able to provide improved wireless circuitry for operating electronic devices.

Wireless electronic device with multiradio controller integrated circuit


A bracket assembly for mounting a mirror is provided. The bracket assembly includes a mirror clamp part, a base support part, and a frame clamp part. The mirror clamp part includes a dome connecting surface engageable with a socket of the mirror to allow rotation of the mirror. The mirror clamp part also includes a first engaging surface having a plurality of first teeth. The bracket assembly also includes a disk member having a plurality of second teeth engageable with the first teeth to allow rotation of the mirror clamp part. The disk member is also coupled to the to the base support part. The frame clamp part is slidable with respect to the base support part for changing a frame receiving opening. The bracket assembly further includes a first tightening mechanism and a second tightening mechanism to selectively vary an impact force required to rotate the mirror.

Off-road vehicles, such as All-Terrain Vehicles (ATV) and Utility Task Vehicles (UTV) are used to carry one or more passengers and/or cargo over different types of terrains. Off-road vehicles are provided with rear view mirrors for facilitating vision toward a rear of the vehicle. The rear-view mirrors are typically mounted onto the vehicle using a bracket assembly attached to a frame of the vehicle. The bracket assembly generally includes a support arm clamped to the frame and hinges for pivotally connecting the rear-view mirror to the support arms. The bracket assembly provides flexibility in allowing positional adjustment of the rear-view mirror for optimum vision.
During operation of the vehicle, the bracket assembly is subjected to continual loads which causes the mirror to vibrate, especially when the vehicle is travelling over rough terrain. These vibrations potentially reduce the usefulness as well as the lifespan of the mirror. Moreover, the bracket assemblies are often collided with structural members, such as poles, trees, bushes, etc., and other vehicles, which may lead to detachment or falling of the mirror from the vehicle.
Accordingly, the brackets need to be robust enough to withstand high loads and flexible enough to allow positional adjustment of the mirror. With recreational interests, new models and makes of off-road vehicles are entering the marketplace with new driving experiences and/or new aesthetics. Existing bracket assemblies are thus rendered obsolete, if the brackets fail to accommodate the changing requirements of new models and make. This may lead to increased material waste which may be difficult for recycling or disposal.


An aspect includes executing, by a binary based floating-point arithmetic unit of a processor, a calculation having two or more operands in hexadecimal format based on a hexadecimal floating-point (HFP) instruction and providing a condition code for a calculation result of the calculation. The floating-point arithmetic unit includes a condition code anticipator circuit that is configured to provide the condition code to the processor prior to availability of the calculation result.

The present invention generally relates to floating point units, and more specifically, to a condition code anticipator (CCA) for a hexadecimal floating point unit.
Floating point numbers are used in computing systems to represent a large range of numbers via a limited number of bits. Floating point numbers are represented by a number value and an exponent associated with that number value. Some computing systems utilize a dedicated unit known as floating point unit to handle floating point numbers computation.
Modern processors use special conditions, like overflow or values of the result such as result equal zero, to branch to a different part of a program. These special conditions and values of the result are called condition codes. To increase performance, it is desirable to have the condition code outcome as soon as possible to determine if a branch instruction that is dependent on the computed floating point operation will take the branch or not.

Condition code anticipator for hexadecimal floating point

INTERNATIONAL BUSINESS MACHINES CORPORATION


A method is used for safely removing a first device from a second device, e.g., removing a first connector from a matching second connector or removing an interface converter from a mother board of a computer. Thus, the loop of the soft strap mounted on the first device allows passage of a user's one finger, so that the user's one finger directly exerts a straight outward force on the loop of the soft strap to easily remove the first device from the second device in a straight manner without producing deflection, thereby removing the first device from the second device easily and safely without damaging the first device or the second device during the pulling process.

1. Field of the Invention
The present invention relates to a method for safely removing a connecting device of a peripheral equipment of a computer, and more particularly to a method for easily and safely removing a first device from a second device, e.g., removing a first connector from a matching second connector or removing an interface converter from a mother board of a computer.
2. Description of the Related Art
A conventional connector 8 in accordance with the prior art shown in FIG. 10 has a first side attached to a serial bus 80 and a second side detachably inserted into a slot 90 of a mother board 9 of a computer. However, the connector 8 only has a smaller portion protruding from the slot 90 of the mother board 9, so that a user has to exert a larger pulling force to pull the connector 8 outward from the slot 90 of the mother board 9. Thus, the connector 8 cannot be directly removed from the slot 90 of the mother board 9 easily and safely, so that the connector 8 and the slot 90 of the mother board 9 are easily damaged during the pulling process due to the larger pulling force.

Method for safely removing connecting device of peripheral equipment of computer


Attachment assemblies for attaching suspension components within a vehicle suspension assembly are provided. First, a bracket assembly having an axle beam utilizes a one piece bracket to improve the structural rigidity of the axle beam and provides the attachment points for the control rods, brake chambers, and air springs. Next, a torsion attachment assembly attaches the torsion assembly to suspension supports using a bushing that fits within a first cylindrical bore in the torsion assembly. A plug is received within a hole in the support and secured to the support by fasteners. A shaft on the plug fits within a second cylindrical bore in the bushing. In this way, the torsion assembly is free to rotate about the plug and the torsion assembly can be easily disconnected from the supports when the fasteners are removed. Finally, a control rod attachment assembly utilizes a pin having tapered ends and a fastening device to secure a control rod end to a supporting structure. The tapered ends of the pin mate with tapered openings in the control rod end and supporting structure. The fastening device ensures that the tapered ends are firmly seated in the tapered openings by pulling the control rod end and supporting structure together.

The present invention relates to improvements to suspension assemblies for vehicles.
Known assemblies used to attach suspension components to one another and to other components in heavy duty truck suspension systems can be expensive and make installation and removal of the suspension components rather difficult. For example, suspension components attach the axle beam to the vehicle frame. Typically, the suspension components have been attached to the axle beam using several individual brackets which increases the cost and complexity of the suspension system.
Another example is the attachment assemblies used to attach torsion assemblies to supports. One prior art device has used split bushes which are clamped around a portion of the torsion assembly. However, this design is susceptible to wear due to ingestion of foreign particles into the assembly. Other prior art devices often require the disassembly of many components to remove the torsion assembly from the supports.
Prior art attachment assemblies used to attach control rods to supporting structures have been relatively expensive. Pins having a cylindrical end and a tapered end have typically been used to connect the control rod to a supporting structure. The cylindrical end is press fit into the supporting structure and the tapered end is received in a complementary tapered opening in an end of the control rod. The tapered end also has a threaded feature that secures the pin to the control rod end. The threaded feature and press fit make the attachment assembly of the prior art more costly and difficult to assemble.

Vehicle suspension attachment assemblies


A crystalline, galliosilicate molecular sieve having the zeolite L type structure and the following composition expressed in terms of oxide mole ratios in the anhydrous state: EQU Ga.sub.2 O.sub.3 :xSiO.sub.2 :yM.sub.2 O:zK.sub.2 O. where M is an alkali metal other than potassium, preferably sodium, x equals at least 3.0, preferably 4 to 10, y equals 0 to 0.9, z equals 0.1 to 1.0, and y+z equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes, preferably hydrocarbon conversion processes, and most preferably hydrocracking and isomerization processes.

This invention relates to crystalline galliosilicates and is particularly concerned with a crystalline galliosilicate molecular sieve having the zeolite L type structure, methods of producing such a molecular sieve, catalysts containing such a molecular sieve and processes for using catalysts containing such a molecular sieve.
Zeolites are well known natural and synthetic molecular sieves that can be defined as crystalline, three-dimensional aluminosilicates consisting essentially of alumina and silica tetrahedra which interlock to form discrete polyhedra. The polyhedra are interconnected to form a framework which encloses cavities or voids interconnected by channels or pores. The size of the cavities and pores will vary depending on the framework structure of the particular zeolite. Normally, the cavities are large enough to accommodate water molecules and large cations which have considerable freedom of movement, thereby permitting sorption, reversible dehydration and ion exchange. The dimensions of the cavities and pores in a zeolite are limited to a small number of values and can vary from structure to structure. Thus, a particular zeolite is capable of sorbing molecules of certain dimensions while rejecting those of dimensions larger than the pore size associated with the zeolite structure. Because of this property zeolites are commonly used as molecular sieves.
In addition to their molecular sieving properties, zeolites show a pronounced selectivity toward polar molecules and molecules with high quadrupole moments. This is due to the ionic nature of the crystals which gives rise to a high nonuniform electric field within the micropores of the zeolite. Molecules which can interact energetically with this field, such as polar or quadrupolar molecules, are therefore sorbed more strongly than nonpolar molecules. This selectivity toward polar molecules is the unique property of zeolites which allows them to be used as drying agents and selective sorbents.
The pore size of a zeolite can vary from about 2.6 Angstroms for analcime to about 10.0 Angstroms for zeolite omega. The term "pore size" as used herein refers to the diameter of the largest molecule that can be sorbed by the particular zeolite or other molecular sieve in question. The measurement of such diameters and pore sizes is discussed more fully in Chapter 8 of the book entitled "Zeolite Molecular Sieves," written by D. W. Breck and published by John Wiley & Sons in 1974, the disclosure of which book is hereby incorporated by reference in its entirety. The pore size range of 2.6 to 10.0 Angstroms is particularly suited for molecular separation and catalytic processing. Analcime will sorb ammonia while excluding larger molecules whereas zeolite omega will sorb perfluorotributyl amine [(C.sub.4 F.sub.9).sub.3 N] while excluding any molecule having a diameter greater than about 10.0 Angstroms. All of the other approximately 150 zeolites now known have pore sizes falling within the range between 2.6 and 10.0 Angstroms.
In addition to their use as drying agents and selective sorbents, zeolites are widely used as components of chemical conversion catalysts. As found in nature or as synthesized, zeolites are typically inactive because they lack acid sites. In general, acid sites are created by subjecting the zeolite to an ion exchange with ammonium ions followed by some type of thermal treatment which creates acid sites by decomposing the ammonium ions into gaseous ammonia and protons. Activated zeolites have been used in many types of chemical conversion processes with the smaller pore zeolites being used to selectively sorb and crack normal and moderately branched chain paraffins.
Because of the unique properties of zeolitic molecular sieves, there have been many attempts at synthesizing new molecular sieves by either substituting an element for the aluminum or silicon present in zeolitic molecular sieves or adding another element in addition to the aluminum and silicon. The term "zeolitic" as used herein refers to molecular sieves whose frameworks are formed of substantially only silica and alumina tetrahedra. One such class of new molecular sieves that has been created is that in which all the framework aluminum has been replaced by gallium. Specifically, it has been reported in the literature that galliosilicate molecular sieves having the faujasite structure, the pentasil structure and the mordenite structure have been synthesized. The synthesis of a galliosilicate analogue of Theta-1 zeolite has also been reported. There has, however, been no reported instance of a sodium-potassium galliosilicate with the zeolite L type structure and containing substantially no aluminum having been synthesized.
Accordingly, it is one of the objects of the present invention to provide a crystalline, galliosilicate molecular sieve with the zeolite L type structure, and a method for preparing such a molecular sieve, which sieve may be useful in many types of chemical conversion processes, particularly hydrocarbon conversion processes. This and other objects of the invention will become more apparent in view of the following description of the invention.

Crystalline galliosilicate with the zeolite L type structure and its use in chemical catalytic conversions


A labeling agent comprising a plurality of nucleotide derivative units represented by Formula (1) below:

Oligonucleotides are known that are substituted at the base moiety with fluorescent dyes such as pyrene and perylene (Non-patent Document 1). These oligonucleotides can be seen as clusters of fluorescent dyes since the fluorescent dyes are arranged along the nucleotide backbone. It is known that when an oligomer having a sequence of multiple fluorescent dyes of the same or different kinds is excited at a single excitation wavelength, fluorescence may be emitted in wavelength bands longer than those of the constituent monomers, or the fluorescence wavelength may vary depending on the sequence of fluorescent dyes. Therefore, it is thought that different detection targets can be detected by their different fluorescent color emissions at a single excitation wavelength by using multiple clusters with difference fluorescent dye sequences as fluorescent labels.    Non-patent Document 1: Kool et al., J.A.C.S. 129, 15426 (2007)

Oligonucleotide derivative, labeling agent and use for labeling agent

Abstract: (where, Z represents a nitrogen atom or CH, Y represents an uncondensed aromatic hydrocarbon group or condensed polycyclic hydrocarbon group, X1 represents O, S or Se, and X2 represents SH (or S−), Se−, a C1-4 alkyl or a morpholino group).


A file transfer application maintains a secure connection over the Internet with a file transfer gateway. A user selects a file and the file transfer application requests a unique ticket from the gateway. The ticket is stored in both the gateway and the file transfer application. Next, the ticket is then encoded in a URL that can be sent to potential recipients of the file via conventional methods. Upon entering the URL into a web browser, the recipient will navigate to the file transfer gateway. The gateway decodes the URL to recover the ticket and looks up the ticket in the database to determine the associated application instance and file description. The gateway will then request the application instance to start encrypting and streaming the contents of the file identified by the ticket to the gateway, which then retransmits the encrypted stream to the recipient's web browser.

One of the many benefits of the Internet is the ability to transfer information electronically between computers with relative ease. For example, with the popularity of the World Wide Web, transferring or downloading a file from a server to a client can be as simple as selecting the file and entering a command to download the file. However, in order to perform a file transfer of this type, both the file source computer and the file destination computer must have the appropriate and compatible software to establish a connection between the computers, to properly format the file to be transferred, and to perform the actual file transfer itself.
Electronic mail, or e-mail, has also become a popular method of communication between computers connected by the Internet. In a typical e-mail system, an e-mail client allows a user to compose a text message, generally via a visual graphic user interface. The e-mail client then interacts with a mail server that forwards the mail, via the Internet to a designated recipient. The standard protocol used for sending Internet e-mail is called SMTP, which is an acronym "Simple Mail Transfer Protocol" and the sending e-mail server is called an SMTP server. When an e-mail client sends an e-mail message, the sender's computer routes the message to an SMTP server. The server examines the e-mail address in the message, and then forwards the message to the recipient's mail server. An SMTP server works in conjunction with a POP server. POP stands for Post Office Protocol and the POP server at the recipient's computer receives e-mail messages from the SMTP server. After receiving an e-mail message, the POP server stores it until the addressee retrieves it.
An e-mail system makes it simple to send and receive text messages. Generally, e-mail systems are able to transmit and receive non-text based "attachments" by encoding files of binary information (such as pictures or images) according to a MIME (Multipurpose Internet Mail Extension) specification so that they appear to be text. For example, when an e-mail server sends an e-mail message with a binary file attachment, the server first retrieves the file from its storage location and then uses a software utility that converts the binary file into a file that is composed of text characters, such as ASCII characters. The "text" file can then be included as part of a text e-mail message. When the message is received, the recipient, or their e-mail program, runs decoding software to convert the "text" file to the original binary file format.
Because binary file attachments are converted into files using text characters, attachments result in a 33% larger file when encoded with Base64 encoding, which is the de facto standard. Large e-mail messages must still be downloaded from the recipient's mail server to the mail client, thereby resulting in sizable download times. In order to manage the download times, many mail systems, especially those systems that operate with low bandwidth Internet systems, such as dial up systems, limit the size of attachments to a predetermined maximum size, for example two megabytes. Any attachments over the predetermined size are either removed by the e-mail server or the e-mail server might refuse to deliver the entire message. This can be a problem for users who regularly sent large attachments, such as multimedia content.
In order to circumvent this problem, file transfer systems that operate outside of the regular e-mail system have been developed. Typically, these systems are server based. A user who wishes to transfer a large file to a recipient first sends the file to a special file server and receives a link to the file from the gateway. The user then sends an e-mail to the recipient with the link as an attachment. When the recipient receives the e-mail with the link, he or she uses the link to navigate to the file server and then download the file from the file server. The file may be encrypted by the file server before downloading.
A problem with the aforementioned systems is that the server becomes a bottleneck, since generally large files must be first uploaded to it, perhaps encrypted and then downloaded from it, often over low bandwidth links. Therefore, there is a need for a simpler file transfer system that does not require uploading a file to a server.

This patent is subject to a terminal disclaimer.


A data processing system is disclosed which monitors client's business orders over time and based upon predetermined criteria determines the client's vested interest in funds deposited into special client accounts. The business order data is stored in uniquely formatted client account files. In addition, a vesting account file stores summary data encompassing all the client files. The data processing system updates and keeps track of client's vesting rights which are subject to change over time. The data processing system's ability to track these and many other conditions is enhanced by a unique set of control status words which control software flow and which are utilized to visually flag important statuses.

Prior art financial management data processing systems are typically first utilized when a client delivers funds to invest. For example, the securities brokerage-cash management system described in U.S. Pat. No. 4,346,442, while monitoring and controlling a wide range of investments, is concerned solely with a data processing system whose action is initiated when an investor directs funds to the cash management system.
The present invention, besides operating in a manner totally distinct from the system described in U.S. Pat. No. 4,346,442, uniquely combines data processing activities that are not normally associated with each other. More specifically, the present invention monitors business orders from participating clients. In addition, the system monitors each client's performance over time based upon predetermined criteria in order to determine the client's vested interest in funds deposited into client "vesting" and "credit" accounts.
The monitored business order data is stored on disk in specially formatted client account files. In addition a unique vesting account file is stored which includes summary data encompassing all the client files.
For clients who exceed the predetermined criteria, the data processing system keeps track of incrementally rising vesting rights and other benefits each participating client receives with respect to each account. Upon meeting the predetermined criteria, 100% of the funds in the "vesting" account can become the property of the client. The "vesting" account also carries with it check writing and undersale privileges.
In addition, for clients who exceed a predetermined level of goods purchased over time, a "credit" account is set up which carries both a life insurance benefit and an incrementally rising line of credit. With respect to the line of credit, if a client's line of credit exceeds a client loan request, the loan is granted and loan processing papers are automatically generated by the system.
The vesting rights associated with these accounts accrue automatically without any action required by the client other than the continuation of normal business transactions. The data processing system's ability to track these and many other conditions is enhanced by the specially designed file formats and a unique set of control status words which control software flow and which are utilized to visually flag important statuses.

Transaction tracking data processing system


There are disclosed a process for purifying ammonia which comprises bringing crude ammonia into contact with a catalyst comprising manganese oxide as an effective ingredient to remove oxygen and/or carbon dioxide that are contained as impurities in the ammonia, and a process for purifying ammonia which comprises bringing crude ammonia into contact with a catalyst comprising manganese oxide as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the crude ammonia. It is made possible by the above process to remove impurities to an extremely low concentration from crude ammonia available on the market for industrial use and crude ammonia from a gallium nitride compound semi-conductor without decomposition of ammonia to generate hydrogen.

1. Field of the Invention
The present invention relates to a process for purifying ammonia. More particularly, the present invention pertains to a process for purifying ammonia, capable of removing impurities such as oxygen, carbon dioxide and water to an extremely low concentration that are contained in ammonia, for instance, crude ammonia available on the market for industrial use or crude ammonia which is recovered from a gallium nitride compound semiconductor process.
2. Description of the Related Arts
Ammonia is used together with silane for the formation of a silicon nitride film and also together with triethyl gallium and the like for the formation of a gallium nitride film each in a semiconductor process. In particular, a production process for a gallium nitride compound semi-conductor which is widely employed as an element for a light emitting diode and laser diode is put into practice usually by subjecting a gallium nitride compound to vapor phase growth on a substrate made of sapphire or the like by means of MOCVD process. Examples of feed gases that are used in the above-mentioned process include a trimethylated group III element such as trimethyl gallium, trimethyl indium and trimethyl aluminum and besides ammonia, that is, a compound of a group V element. Accompanying the progress in film formation technique in recent year, ammonia to be used therein is forcefully required to have an extremely high purity. Because of the aforesaid requirement and a large amount to be used, there is required to develop a process for purifying ammonia capable of continuously supplying highly pure ammonia.
In general, ammonia available on the market for industrial use contains oxygen, carbon dioxide, moisture, etc. Ammonia having a relatively high purity is marketed in the form obtained by further distilling or rectifying the ammonia available on the market, or in the form obtained by further diluting with a highly pure inert gas. However, since ammonia to be used as a feed gas in a semiconductor process and the like as mentioned above is required to have an extremely high purity, there has hitherto been developed a process for further purifying ammonia having a relatively high purity obtained by further distilling or rectifying ammonia for industrial use.
As a process for purifying ammonia, there have previously been available {circle around (1)} an ammonia purifying process in which carbon dioxide gas in crude ammonia is adsorptively removed by passing crude ammonia through a solid alkali layer maintained at such a temperature as higher than the temperature at which the solid alkali is no longer dissolved due to the deliquescent property of the solid alkali and also at such a temperature as lower than the melting point thereof {refer to Japanese Patent Application Laid-Open No. 24737/1994 (Heisei 6)} and {circle around (2)} an ammonia purifying process in which moisture in crude ammonia is removed by bringing the crude ammonia into contact with BaO as a simple substance or a mixture comprising BaO as s principal component under the condition of substantially room temperature {refer to Japanese Patent Application Laid-Open No. 142833/1997(Heisei 9)}.
In addition, there have also been developed {circle around (3)} an ammonia purifying process in which oxygen contained in crude ammonia is removed by bringing the crude ammonia into contact with a catalyst comprising nickel as a principal component {refer to Japanese Patent Application Laid-Open No. 124813/1993(Heisei 5)}, {circle around (4)} an ammonia purifying process in which carbon monoxide and carbon dioxide that are contained in crude ammonia are removed by bringing the crude ammonia into contact with a catalyst comprising nickel as a principal component {refer to Japanese Patent Application Laid-Open No. 107412/1994 (Heisei 6)}, etc.
However, the ammonia purifying processes {circle around (1)} and {circle around (2)} have suffered from the disadvantages in that although the process {circle around (1)} can remove only carbon dioxide gas and the process {circle around (2)} can remove only moisture, each of the processes must be frequently combined with an other process to purify the ammonia in order that the process is employed in a semiconductor process. Moreover with regard to the ammonia purifying processes {circle around (3)} and {circle around (4)}, in the case of a high contact temperature between the catalyst and ammonia, there is a fear of hydrogen generation due to ammonia decomposition, hence necessitating to purify the ammonia by maintaining the contact temperature at around ordinary temperature. Further, in the above-mentioned gallium nitride compound semiconductor process, because of low decomposition efficiency of ammonia, an extremely large amount thereof is required to be used as the feed gas compared with trimethylated group III element such as trimethyl gallium, trimethyl indium and trimethyl aluminum. The ammonia employed as the feed gas in the foregoing semiconductor process is highly pure ammonia which is obtained by distilling or rectifying ammonia for industrial use, or is ammonia obtained by further purifying the aforesaid highly pure ammonia. Thus, it has been impossible to employ ammonia available on the market for industrial use as it is.
In addition thereto, the ammonia available on the market subjected to distillation or rectification costs several ten times as compared with ammonia available on the market for industrial use.
By the reasons mentioned hereinbefore, the ammonia available on the market subjected to distillation or rectification suffers from the drawback in that it leads to an extremely high running cost, particularly in a gallium nitride compound semiconductor process, and what is more, most of it has been discarded in a large amount without being reacted or utilized in the above-mentioned process. In such circumstances, it has eagerly been desired to develop an ammonia purification process capable of continuously supplying the semiconductor process with ammonia, and at the same time, of contributing to the production of the semiconductor at a reasonable cost.
Further, most of the ammonia having extremely high purity, after being exhausted from the semiconductor process, has been treated by a wet absorption process, a combustion treatment process, a dry adsorption process or a decomposition treatment process. However, the above-mentioned processes involves such problems still remain unsolved as described hereunder. The wet absorption process which comprises neutralizing the ammonia by passing it through an acidic aqueous solution is problematic in the post treatment of by-produced ammonium salts. The combustion treatment process which comprises burning the ammonia by introducing into the flame of a fuel such as propane is problematic in fuel consumption, NOx treatment and CO2 generation. The dry adsorption process which comprises bringing the ammonia into contact with a chemical agent having chemical reactivity with the ammonia is problematic in high running cost due to the use of an expensive chemical agent. The decomposition treatment which comprises decomposing the ammonia into nitrogen and hydrogen by bringing the ammonia into contact with an ammonia decomposition catalyst is problematic in high running cost due to large electric power consumption.
An efficient recovery and recycle of the ammonia thus used, if made possible, can contribute to not only the effective utilization of a resource but also environmental preservation.
Under such circumstances, a general object of the present invention is to provide a process for purifying ammonia, capable of removing impurities such as oxygen, carbon dioxide and moisture that are contained in ammonia each in a slight amount to an extremely low concentration, and of preventing hydrogen from being generated by the decomposition of ammonia even at a relatively high contact temperature.
Another object of the present invention is to provide a process for purifying ammonia, capable of readily producing ammonia which is usable as a feed gas for a gallium nitride-compound semiconductor from crude ammonia available on the market for industrial use or crude ammonia which is recovered from a gallium nitride compound semiconductor process.
Other objects of the present invention will be obvious from the text of this specification hereinafter disclosed. Under such circumstances, intensive extensive research and investigation were made by the present inventors in order to achieve the above-mentioned object. As a result, it has been found that oxygen, carbon dioxide and moisture contained in crude ammonia as impurities can be removed to as low as 0.1 ppm or to less than 0.01 ppm by bringing the crude ammonia into contact with a catalyst comprising manganese oxide as an effective ingredient, preferably further with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 or equivalent and that manganese oxide is a catalyst which is less prone to decompose ammonia. Such finding led to the ammonia purification process according to one aspect of the present invention.
In addition, it has been found that, if it is made possible to remove oxygen, carbon dioxide and moisture which exert evil influence upon a gallium nitride compound semiconductor process each to an extremely low concentration from crude ammonia available on the market for industrial use or from crude ammonia recovered out of a gallium nitride compound semiconductor process, then the purified ammonia can be used as a feed gas to a gallium nitride compound semiconductor.
Moreover, it has been found that oxygen, carbon dioxide and moisture contained as impurities in crude ammonia available on the market for industrial use or in crude ammonia recovered from a gallium nitride compound semiconductor process can be removed to as low as 0.1 ppm or to less than 0.01 ppm by bringing the crude ammonia into contact with a catalyst comprising manganese oxide and/or nickel as an effective ingredient, and further with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 or equivalent. Such finding led to the ammonia purification process according to another aspect of the present invention.
That is to say, the present invention provides:
1. A process for purifying ammonia which comprises bringing crude ammonia into contact with a catalyst comprising manganese oxide as an effective ingredient to remove oxygen and/or carbon dioxide that are contained as impurities in the foregoing crude ammonia.
2. A process for purifying ammonia which comprises bringing crude ammonia into contact with a catalyst comprising manganese oxide as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
3. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises bringing crude ammonia available on the market for industrial use into contact with a catalyst comprising manganese oxide as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
4. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises bringing crude ammonia available on the market for industrial use into contact with a catalyst comprising nickel as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
5. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises bringing crude ammonia available on the market for industrial use into contact with a catalyst comprising manganese oxide as an effective ingredient and with a catalyst comprising nickel as an effective ingredient consecutively in this order, and thereafter bringing the ammonia into contact with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
6. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises bringing crude ammonia available on the market for industrial use into contact with a catalyst comprising nickel as an effective ingredient and with a catalyst comprising manganese oxide as an effective ingredient consecutively in this order, and thereafter bringing the ammonia into contact with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
7. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises the step of bringing crude ammonia available on the market for industrial use into contact with a catalyst comprising manganese oxide as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 and the step of bringing the ammonia from the synthetic zeolite into contact with a catalyst comprising nickel as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 consecutively in this order to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
8. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises the step of bringing crude ammonia available on the market for industrial use into contact with a catalyst comprising nickel as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 and the step of bringing the ammonia from the synthetic zeolite into contact with a catalyst comprising manganese oxide as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 consecutively in this order to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
9. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises bringing crude ammonia recovered from a a gallium nitride compound semiconductor process into contact with a catalyst comprising manganese oxide as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.
10. A process for purifying ammonia to be used as a feed gas for a gallium nitride compound semiconductor which comprises bringing crude ammonia recovered from a gallium nitride compound semiconductor process into contact with a catalyst comprising nickel as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 xc3x85 to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the foregoing crude ammonia.


The invention provides a hub document preparation method which collects a plurality of external files and attachment files to be included in a structured document of a hub document format to allow a hub document to be prepared readily, to reduce the burden to a document preparing person, and to augment the operation and efficiency of preparing a hub document.

1) Field of the Invention
This invention relates to a hub document preparation method for preparing a single structured document of the hub document format such as, for example, an SGML (Standard Generalized Markup Language) document from a plurality of non-structured documents such as, for example, documents prepared on a word processor.
2) Description of the Related Art
Various structured documents are conventionally known and include an SGML (Standard Generalized Markup Language) document and an XML (Extended Markup Language) document in which document contents are represented in a text format excluding layout information and so forth from document data. Such structured documents as an SGML document and an XML document allow definition of a logical structure of the document by adding a mark called tag for identifying the structure of the document and are progressively spread as standard language documents for storage/search or exchange of a document.
FIG. 8 illustrates a structure of an SGML document. In the following, a structured document is described taking an SGML document as an example with reference to FIG. 8.
Generally, an SGML document 20 is composed of an SGML declaration 21 which describes various references such as types of codes used in the document, a DTD (Document Type Definition) 22 which defines mutual relationships of document elements, that is, a document structure, and a document instance 23 representative of document contents.
The DTD 22 defines tags to be applied to elements of the document such as an index, the body of the document, and a list. More particularly, the DTD 22 includes element declarations which define the elements of the document, relationships of inclusion of elements, an order in which the elements are to be arranged, a number of times of appearance of each element and so forth, attribute declarations which define attributes of the elements, entity declarations which declare methods of taking special characters, pictures or the like into the document, and so forth. The DTD 22 allows definitions of memberships, an order of appearance, numbers of times of appearance and so forth of tags in a tree structure.
In order to prepare the SGML document 20, a document structure of the SGML document 20, that is, the DTD 22, is prepared or acquired first, and then the document instance 23 which fits with the DTD 22 is prepared.
The document instance 23 may have a graphic file, which includes graphic information, or a like file attached thereto. In the following description, a file attached to the document instance 23 in this manner is referred to as attachment file.
Upon preparation of the SGML declaration 21 or the DTD 22, various definition contents (declarations and so forth) may be described directly in the SGML declaration 21 or the DTD 22 as described above, or such definition contents may be described in an external file (external entity) 21a or 22a stored in an external area 25 in advance such that the external file 21a or 22a may be designated by the SGML declaration 21 or DTD 22 (external entity declaration).
Though not illustrated in FIG. 8, upon preparation of the document instance 23, document contents of the document instance 23 may be described in an external file in advance so as to allow the external file to be designated by the document instance 23 of the SGML document 20 (external entity declaration) similarly as upon preparation of the SGML declaration 21 or DTD 22.
The external file designated by the external entity declaration by the document instance 23 may have an attachment file attached thereto. In this instance, an external entity declaration for declaring the entity of the attachment file is prepared.
FIG. 9 illustrates a structure of an SGML document (hub document format structured document) 30 of the hub document format. Referring to FIG. 9, contents of an SGML declaration and a DTD are prepared and described in external files (external entities) 31 and 32, respectively, while a plurality of (two in FIG. 9) document contents (document instances) are prepared and described in external files 33a and 33b, respectively, and the external files 31, 32, 33a and 33b are designated (external entity declaration) by a hub document 35 to prepare the single SGML document 30 of a hub document format.
The SGML document 30 of such a hub document format as described above is suitable as a document wherein document contents are described in detail in a great number of parts, for example, such as a maintenance manual or the like, and is generally suitable to combine contents (instances) of a plurality of documents prepared on a word processor or a like document preparing system into a single SGML document such as the SGML document 30.
It is to be noted that an authoring tool in most cases prepares one SGML document by adding an SGML declaration and a DTD to one document instance (one file) as seen in FIG. 8.
Upon preparation of such a hub document 35 as described above, the preparing person first collects a plurality of external files to be included into the SGML document 30 of the hub document format, and then prepares entity declarations (ENTITY statements) for individually referring to the entities of the external files.
However, in such a conventional hub document preparation method as described above, in order to designate the external files with the external entity declarations, the preparing person must collect necessary external files.
For example, in order to designate the external files 31, 32, 33a and 33b, which are discretely located on the computer system and in which document instances and so forth are stored individually, with external entity declarations, the external files 31, 32, 33a and 33b must be located after the stored locations of them are checked. Therefore, the conventional hub document preparation method described above has a subject to be solved in that the operation just described is cumbersome and makes a heavy burden to the preparing person, and besides much time is required for the preparation of the hub document 35 and the operation efficiency is low.
Further, where a document instance has an attachment file such as a graphic file added thereto, in order to prepare an entity declaration (ENTITY statement) for referring to the entity of the attachment file, not only an external file of the document instance must be collected but also the stored location of the attachment file must be checked to collect the attachment file. Consequently, the conventional hub document preparation method described above has another subject to be solved in that the presence of such an attachment file as described above further increases the burden to the preparing person and increasing time is required for preparation of the hub document 35 and besides the operation efficiency is deteriorated.


A structure and method for testing multi-port SRAM cells includes a test controller connected to at least one multi-port SRAM cell (the test controller is adapted to store a pattern into the multi-port SRAM cell and generate a stability test restore clamp), a read/write controller connected to the multi-port SRAM cell (the read/write controller is adapted to simultaneously activate a plurality of wordline ports on the multi-port SRAM cell while the stability test restore clamp is enabled), and a timing control circuit connected to the read/write controller. The timing control circuit is adapted to vary an activation time of the wordline ports. The read/write controller reads from the multi-port SRAM after the stability test restore clamp is deactivated. The read/write controller activates the wordline ports for each multi-port SRAM cell in an array sequentially while all bitlines in the array are held on by the stability test restore clamp. The structure also includes a logic device connected to the test controller adapted to prevent the stability test restore clamp from being enabled unless a test is being performed. The timing control circuit is adapted to be selectively externally controllable to vary the activation time of the wordline ports. The timing control circuit can include a plurality of delay units adapted to be selectively engaged to vary the activation time of the wordline ports. The stability test restore clamp is enabled for at least a wordline pulse.

1. Field of the Invention
The present invention generally relates to testing of computer memory cells and more particularly to an improved method and system for testing multi-port SRAM cells that tests the situation where multiple ports are accessed within a critical time.
2. Description of the Related Art
Multi-port static random access memory SRAM cells are well known in the art. For example, as shown in FIG. 1, a conventional 2-port SRAM cell includes cross-coupled inverters 100 connected to NFET transistors 101-104. The 2-port SRAM cell is bordered by the port A wordline select 125, the port B wordline select 126, the port A bitline true and complement 115, 116 and the port B bitline true and complement 120, 121. All wordlines 125, 126 and bitlines 115, 116, 120, 121 are connected to an addressing unit and a read/write controller which controls the writing to and reading from the selected SRAM cell. FIG. 1 also illustrates bitline restore devices 105.varies.108 (PFET transistors) that are connected to voltage sources 130 and the port A bitline restore select line 110 and the port B bitline restore select line 111.
In operation, a read cycle begins with bitline restore control lines 110 and 111 in the low state (voltage at ground) and bitline pairs 115, 116 and 120, 121, respectively, in the precharged high state (voltage at Vdd). Wordlines 125 and 126 also start in the low state. The internal storage nodes start in a state where one of them (150 or 151) is in the high state and the other (151 or 150) is in the low state. For example, assume that node 150 (complement node) starts in the low state and node 151 (true node) starts in the high state. This would reflect a logical "one" stored in the cell.
For a port A read operation, node "Restore A"(110) switches to the high state, turning off PFETs 105, 107 and 141 and tri-stating port A's true and complement bitlines 115, 116. Port A's wordline125 switches to the high state, turning on NFETs 101 and 103 and connecting port A true and complement bitlines (115 and 116) to the internal storage nodes of the cell. In this example, bitline115 will remain in the high state while bitline116's capacitance discharges into the cell node (150) that is in the low state. This causes the voltage on node 150 to rise "slightly" until the bitline116 is fully discharged, at which point, node 150's voltage returns to ground. If this low internal node (150) rises significantly, it can cause the cell nodes to fully switch, thereby causing the cell's stored data to change it's logical value from a "one" to a "zero". This problem is commonly referred to, by those skilled in the art, as "read instability". A static SRAM cell must be designed to be "read stable". Furthermore, an adequate test for an SRAM cell will stress the "read instability" condition.
To complete the cycle, the port A wordline (125) switches to the low state, thereby disconnecting the bitlines from the cell's internal storage nodes (150, 151). The port A restore line (110) then switches to the low state, turning on PFETs 105, 107 and 141, which in turn precharges the bitlines 115 and 116. The cell data has been read, and all nodes have returned to their original starting state.
For a Port B read operation, the circuit would behave similarly, utilizing restore select line 111, wordline 126 and bitlines 120, 121. Read stability for a Port B read operation will be equally important. As important as this is for a single port read operation, the read stability of the SRAM cell becomes even more important for multi-port memories.
In the illustrated dual-port SRAM cell, one must consider the read stability of the internal storage nodes 150, 151 when accessing data through both ports A and B simultaneously. For example, when both ports A and B in the dual-port static random access memory (SRAM) cell (containing a logical "one") are read simultaneous, both bitlines (e.g., 116, 121) discharge simultaneously into the same "low state" internal storage node (i.e., 150) of the cell. As a result, the increased current into the cell causes the internal "low state" node (150) to rise significantly more than during the previously described single port read access. The maximum read instability will occur when both ports are accessed at precisely the same time.
A dual-port memory cell of such a design must be designed such that, given the absence of any manufacturing defects, the cell will retain it's data for the worst case "read instability" read operation. To those skilled in the art, it is readily apparent that such a design may be achieved by utilizing transistor sizes within the cell, such that the read stability is optimized. Furthermore, it is also understood that process variation must be taken into account when deciding upon transistor sizes.
However, regardless of how well a cell is designed with respect to "read instability", a manufacturing process defect mechanism may occur within the cell, such that the "read stability" of the cell is compromised. It is important to test all cells for the presence of such a defect, prior to delivering products containing the above-mentioned cell design.
Therefore, it is important during testing to determine whether the 2-port SRAM cell will remain stable when both ports are simultaneously accessed. One might attempt to test the cell for read stability by actually accessing the cell from both ports simultaneously. However, performing a test which activates both ports simultaneously has posed a unique challenge to the test community in the past.
More specifically, it is very difficult to match the activation of bitline pair A 115-116 and bitline pair B 120-121, principally because of the different delay paths which precede the different bitline pairs. This is especially true because the bitlines will be activated for a very short period (e.g., picoseconds). Therefore, if the bitlines are not activated within picoseconds of each other, there will not be simultaneous activation.
Only tester clock edge schmooing techniques have been able to conventionally test the read stability of 2-port SRAM cell. Such techniques involve repeatedly adjusting one bitline's clock signal over a range while holding the other bitline's clock signal consistent. In this way, the schmooing technique hopes to simultaneously activate the different bitlines. However, due to time-step granularity limitations, even with such techniques, a simultaneous activation is not guaranteed.
Further, such schmooing techniques have certain limitations, one of which is the difficulty or impracticality of applying clock schmooing when built-in self-test (BIST) methods are employed to test the array at manufacturing test. This is because BIST utilizes only one clock path to access the cell from either port A or B. With only one clock during BIST, it is fundamentally impractical to use a schmooing technique.
Another serious limitation of this technique, and perhaps the most significant, is the prohibitive test time and associated cost involved with schmooing techniques. Schmooing techniques require multiple passes of reading each cell, perhaps as many as several hundred or more passes. Additionally, such techniques do not lend themselves to gathering the large amounts of data required for adequate bit fail mapping.
The invention described below provides an alternative to schmooing that is less time intensive and less expensive.

Self-test method for testing read stability in a dual-port SRAM cell

International Business Machines Corporation


A method of managing a page buffer of a non-volatile memory device comprises programming least significant bit (LSB) page data from an LSB page buffer into a page of memory cells, and retaining the LSB page data in the LSB page buffer until most significant bit (MSB) page data corresponding to the LSB page data is programmed in the page.

Embodiments of the inventive concept relate generally to methods and apparatuses for controlling a page buffer of a non-volatile memory device. More particularly, embodiments of the inventive concept relate to methods and apparatuses for managing a page buffer to retain least significant bit (LSB) page data until programming of most significant bit (MSB) page data is completed.
In an effort to increase the storage density of non-volatile memory devices, researchers have developed non-volatile memory devices that can store more than one bit of data per memory cell. For instance, researchers have developed flash memory devices that can store two or more bits per memory cell. Such memory devices are commonly referred to as multi-level cell (MLC) devices.
In some MLC devices, selected memory cells are programmed by first programming lower order bits, such as LSB bits, and then programming upper order bits, such as MSB bits. The selected memory cells can be arranged in pages, where each page comprises a plurality of memory cells connected to a common word line. A page of memory cells in an MLC device can be programmed with a page of LSB data, referred to as LSB page data, and subsequently programmed with a page of MSB data, referred to as MSB page data.
Because the MSB page data is generally programmed after the LSB page data, a failure to properly program the MSB page data can disturb the previously programmed LSB page data.

Method and apparatus for controlling page buffer of non-volatile memory device


A new and distinct cultivar of Rhododendron plant named ‘NCRX8’ having prolific, bright cherry-red single flowers, cold hardy to USDA Zone 6b, consistent Fall reblooming, and a dense, compact habit. The new cultivar is a Rhododendron, suitable for ornamental garden purposes.

The present invention comprises a new and distinct hybrid evergreen azalea cultivar hereinafter referred to by the cultivar name 'NCRX8'. This hybrid azalea was developed by a controlled breeding program at North Carolina State University, in Mills River, N.C. 'NCRX8' was selected for its single, cherry-red flowers, floriferousness, dense and compact growth habit, and consistent Fall reblooming. It was selected from the controlled, hand pollination of emasculated female experimental hybrid H2009-242-026 (unpatented) and male/pollen parent experimental hybrid H2009-308-006 (unpatented). 'NCRX8' was selected from this population of seedlings after 5 years in trials at the Mountain Horticultural Crops Research and Extension Center in Mills River, N.C.
Container trials were conducted using pine bark media supplemented with 1.04 kg·m−3 dolomitic lime, 0.74 kg·m−3 granulated micronutrients (Micromax; ICL Specialty Fertilizers, Tel Aviv, Israel) and top-dressed with 5- to 6-month slow-release fertilizer (Osmocote Plus 15-9-12, ICL Specialty Fertilizers). Full-sun field trials were conducted in plastic-covered, bark-amended clay soils with minimum winter temperatures of −2° F. (−19° C.) and maximum summer temperatures 98° F. (37° C.). The first asexual propagation of 'NCRX8' occurred in 2015 by rooting stem cuttings at the North Carolina State University Mountain Horticultural Crops Research Station, Mills River, N.C. 'NCRX8' roots readily from firm softwood cuttings treated with a basal dip of 3,000-5,000 ppm indole butyric acid (potassium salt) in water. 'NCRX8' has been found to retain its distinctive characteristics through successive asexual propagations over 6 years.


An electric rotary machine includes a rotor and a stator. The rotor includes a rotor shaft having a refrigerant flow path therein, a rotor core, a plurality of magnet pole portions, a first end plate and a second end plate. The stator includes a first coil end located radially outside the first end plate, and a second coil end located radially outside of the second end plate. The first end plate includes a first refrigerant discharge hole, a first groove portion communicating with the refrigerant flow path and communicating with the first refrigerant discharge hole, and a second groove portion communicating with the refrigerant flow path and the core through hole. The second end plate includes a second refrigerant discharge hole communicating with the refrigerant flow path via the core through hole and the second groove portion, without directly communicating with the refrigerant flow path.

With the recent increase in size of electric rotary machines, the deterioration of the performance of the electric rotary machine caused due to the heat generated from the magnet pole portion is not negligible, and accordingly, studies have been conducted to find a method of efficiently cooling the magnet pole portion of the rotor. Meanwhile, since the coils of the stator also generate heat, the coils of the stator also need to be cooled.
Japanese Unexamined Patent Application Publication Nos. 9-182374 and 9-182375 describe a rotor of an electric rotary machine including a rotor shaft in which a refrigerant flow path is formed, a rotor core, a magnet pole portion, and a pair of end face plates disposed on both end faces of the rotor core. In this rotor, a refrigerant is supplied to both end face plates from the refrigerant flow path of the rotor shaft, respectively. The refrigerant supplied to one end face plate is discharged from the other end face plate through a through hole formed in the rotor core. Further, it is described that the refrigerant supplied to the other end face plate is discharged from the one end face plate through the other through hole formed in the rotor core. As a result, it is possible to cool the coil ends on both sides of the stator that face the rotor, while cooling the rotor core from inside.
However, in the rotors of the electric rotary machines described in above-mentioned PTLs 1 and 2, it is difficult to uniformly supply refrigerant from the refrigerant flow path of the rotor shaft to one and the other end surface sides, and it is not possible to control flow rate distribution properly. In addition, it is necessary to process the refrigerant supply path extending in a radial direction from the refrigerant flow path at two positions of one and the other end surface sides of the rotor shaft, resulting in increased processing cost.


A process for producing coarse-grained sintered magnesia. The starting material is an active, reactive pulverulent magnesium oxide having a grain size of <0.15 mm and green compacts are formned from this magnesium oxide by pelletising on a granulating disc at a material throughput of less than 250 kg of MgO/m.sup.2 disc area and per hour, which are subsequently subjected to sinter-firing at high temperature.

The invention relates to a process for producing coarse-grained sintered magnesia, starting from a pulverulent magnesium oxide, converting this into green compacts and subjecting the green compacts to sinterfiring at high temperature.
To obtain the desired high-temperature strength in sintered magnesia products, it is necessary to achieve a sufficiently high density of the sintered magnesia, which is usually abbreviated to "sinter". As a rule, an apparent density of the sintered magnesia of 3.3 g/cm.sup.3 is regarded as a minimum value, but the aim is to reach apparent densities above 3.4 g/cm.sup.3. In order to meet this aim, the green compacts which are to be subjected to the sintering treatment at high temperature, at which deadburning of the material takes place, must already have a sufficiently high density of at least about 1.7 g/cm.sup.3, but preferably more than 2.3 g/cm.sup.3, and a structure which tends to give considerable compaction on mild firing. To form such green compacts, magnesium oxide has hitherto been compacted by means of mechanical presses, so-called briquetting roller presses having in particular been used for this compaction. However, the use of mechanical presses for the formation of green compacts of a density which meets the abovementioned demands, requires a relatively large investment expense and, in operation, the consumption of considerable quantities of energy, because very high forces must be applied for compacting the pulverulent magnesium oxide. In spite of the application of high forces, however, a relatively large proportion of the green compacts provided by the presses has an unduly low mechanical strength. Such green compacts disintegrate during the manipulation which follows pressing and, for reprocessing the material which was contained in these green compacts, this material must be screened off and subjected to repeated pressing, which results in a considerable increase in the energy consumption required for pressing and a corresponding decrease in the production output of the presses, since, in fact, a considerable part of the magnesium oxide to be processed must be compacted several times.


An implantable device for delivering a therapeutic agent to treat an ear of a patient includes a body having a distal end region and a proximal end region. The body defines, at least in part, a reservoir configured to contain the therapeutic agent. The device includes a shaft attached to the distal end region of the body and a lumen extending through the shaft having at least one inlet at a proximal end region in fluid communication with the reservoir and at least one outlet at a distal end region. Upon implantation of the body in a region of the ear, a length of the shaft is sufficient to extend from the body to at least the round window membrane of the ear. The device is configured to deliver the therapeutic agent to the ear from the reservoir via passive diffusion. Related devices and methods are described.

When the ear is functioning normally, sound waves travel through the air to the outer ear, which collects the sound and directs it through the ear canal to the middle ear. The sound waves strike the eardrum, or tympanic membrane, and cause it to vibrate. This vibration is transmitted to the cochlea by the middle ear bones, called ossicles. The three ossicles that comprise the ossicular chain are termed the malleus, incus and stapes, but are also commonly referred to as the "hammer", "anvil" and "stirrup", respectively. Motion of these bones, transmits sound pressure waves arriving at the eardrum to the cochlea's oval window membrane, which in turn, gives rise to a travelling displacement wave within the cochlea.
The inner ear consists of the bony labyrinth, a system of passages making up the following two main functional parts: 1) the cochlea, which is dedicated to hearing, and 2) the vestibular system, which is dedicated to balance. The cochlea is lined with thousands of tiny sensory receptors, commonly referred to as hair cells, that are arranged in rows along the basilar membrane. As the basilar membrane vibrates in response to incoming pressure waves, the hair cells transduce this mechanical motion into electrical impulses that result in neurotransmitter release and excitation of the auditory neurons. Afferent signaling from the auditory neurons is then processed and transmitted by a series of neural connections all the way to the cortex, where sound is perceived.
Hearing loss is the most common sensory impairment in humans, affecting over 5% of individuals in industrialized nations. It is also an important health problem in the elderly, and 40% of the population aged 65 years or older have a hearing loss great enough to impair communication.
Hearing loss can be a result of a variety of auditory disorders. Conductive Hearing Loss (CHL) involves the loss of normal mechanical pathways for sound to reach the hair cells in the cochlea, for example by anatomical malformations/anomalies, ear infections, allergies, tumors, bone remodeling, and/or damage to the ossicles. Sensorineural Hearing Loss (SNHL) is due to impaired ability of the cochlea to effectively transduce pressure waves into neural signaling. SNHL is typically associated with exposure to loud noise, aging, head trauma, exposure to ototoxic drugs, infection, autoimmune disease, Meniere's disease, genetic mutations, tumors of the auditory nerve and the like.
Although new therapies to treat hearing loss are emerging, there is a need for safe, direct, efficient and effective drug delivery devices. Methods capable of providing long-term drug delivery for sustained therapeutic effect in treating hearing loss and other maladies of the ear represent unmet medical needs. These needs are particularly pronounced for ailments affecting the inner ear including areas in and around the cochlea, semicircular canals, vestibule for example.

Inner ear drug delivery devices and methods of use


A method and system for producing a synthesis gas in an oxygen transport membrane based reforming system is disclosed that carries out an air heated pre-reforming process, a primary reforming process, a secondary reforming process.

Synthesis gas containing hydrogen and carbon monoxide is produced for a variety of industrial applications, for example, the production of hydrogen, chemicals and synthetic fuel production. Conventionally, the synthesis gas is produced in a fired reformer in which natural gas and steam is reformed in nickel catalyst containing reformer tubes at high temperatures (e.g., 850° C. to 1000° C.) and moderate pressures (e.g., 16 to 30 bar) to produce the synthesis gas. The endothermic heating requirements for steam methane reforming reactions occurring within the reformer tubes are provided by burners firing into the furnace that are fueled by part of the natural gas. In order to increase the hydrogen content of the synthesis gas produced by the steam methane reforming (SMR) process, the synthesis gas can be subjected to water-gas shift reactions to react residual steam in the synthesis gas with the carbon monoxide.
A well-established alternative to steam methane reforming is the non-catalytic partial oxidation process (POx) whereby a substoichiometric amount of oxygen is allowed to react with the natural gas feed creating steam and carbon dioxide at high temperatures. The high temperature residual methane is reformed through reactions with the high temperature steam and carbon dioxide.
An attractive alternative process for producing synthesis gas is the autothermal reformer (ATR) process which uses oxidation to produce heat with a catalyst to permit reforming to occur at lower temperatures than the POx process. Similar to the POx process, oxygen is required to partially oxidize natural gas in a burner to provide heat, high temperature carbon dioxide and steam to reform the residual methane. Normally some steam needs to be added to the natural gas to control carbon formation on the catalyst. However, both the ATR as well as POx processes require separate air separation units (ASU) to produce high-pressure oxygen, which adds complexity as well as capital and operating cost to the overall process.
When the feedstock contains significant amounts of heavy hydrocarbons, SMR and ATR processes, are typically preceded by a pre-reforming step. Pre-reforming is a catalyst based process for converting higher hydrocarbons to methane, hydrogen, carbon monoxide and carbon dioxide. The reactions involved in pre-reforming are endothermic. Most pre-reformers operate adiabatically, and thus the pre-reformed feedstock leaves at a much lower temperature than the feedstock entering the pre-reformer. Another process that will be discussed in this invention is the secondary reforming process, which is essentially an autothermal process that is fed the product from a steam methane reforming process. Thus, the feed to a secondary reforming process is primarily synthesis gas from steam methane reforming. Depending on the end application, some natural gas may bypass the SMR process and be directly introduced into the secondary reforming step. Also, when a SMR process is followed by a secondary reforming process, the SMR may operate at a lower temperature, e.g. 650° C. to 825° C. versus 850° C. to 1000° C.
As can be appreciated, the conventional methods of producing a synthesis gas such as have been discussed above are expensive and require complex installations. To overcome the complexity and expense of such installations it has been proposed to generate the synthesis gas within reactors that utilize an oxygen transport membrane to supply oxygen and thereby generate the heat necessary to support endothermic heating requirements of the steam methane reforming reactions. A typical oxygen transport membrane has a dense layer that, while being impervious to air or other oxygen containing gas, will transport oxygen ions when subjected to an elevated operational temperature and a difference in oxygen partial pressure across the membrane.
Examples of oxygen transport membrane based reforming systems used in the production of synthesis gas can be found in U.S. Pat. Nos. 6,048,472; 6,110,979; 6,114,400; 6,296,686; 7,261,751; 8,262,755; and 8,419,827. There is an operational problem with all of these oxygen transport membrane based systems because such oxygen transport membranes need to operate at high temperatures of around 900° C. to 1100° C. Where hydrocarbons such as methane and higher order hydrocarbons are subjected to such high temperatures within the oxygen transport membrane, excessive carbon formation occurs, especially at high pressures and low steam to carbon ratios. The carbon formation problems are particularly severe in the above-identified prior art oxygen transport membrane based systems. A different approach to using an oxygen transport membrane based reforming system in the production of synthesis gas is disclosed in U.S. Pat. No. 8,349,214 which provides an oxygen transport membrane based reforming system that uses hydrogen and carbon monoxide as part of the reactant gas feed to the oxygen transport membrane tubes and minimizes the hydrocarbon content of the feed entering the permeate side of the oxygen transport membrane tubes. Excess heat generated within the oxygen transport membrane tubes is transported mainly by radiation to the reforming tubes made of conventional materials. Use of low hydrocarbon content high hydrogen and carbon monoxide feed to the oxygen transport membrane tubes addresses many of the highlighted problems with the earlier oxygen transport membrane systems.
Other problems that arise with the prior art oxygen transport membrane based reforming systems are the cost of the oxygen transport membrane modules and the lower than desired durability, reliability and operating availability of such oxygen transport membrane based reforming systems. These problems are the primary reasons that oxygen transport membranes based reforming systems have not been successfully commercialized. Advances in oxygen transport membrane materials have addressed problems associated with oxygen flux, membrane degradation and creep life, but there is much work left to be done to achieve commercially viable oxygen transport membrane based reforming systems from a cost standpoint as well as from an operating reliability and availability standpoint.
The present invention addresses the aforementioned problems by providing an improved process for making synthesis gas using a reactively-driven oxygen transport membrane based system, which consists of two reactors that can be in the form of sets of catalyst containing tubes—reforming reactor and oxygen transport membrane reactor. Partial oxidation and some reforming occurs at the permeate (catalyst containing) side of the oxygen transport membranes and a reforming process facilitated by a reformer catalyst occurs in the reforming reactor in close proximity to the oxygen transport membrane reactor. The partial oxidation process, which is exothermic, and the reforming process, which is endothermic, both occur within the oxygen transport membrane based system and thus have a high degree of thermal integration so that heat released in the oxidation process supplies the heat absorbed by the reforming process.
The methanol production process generally involves directing a compressed synthesis gas comprising hydrogen, carbon monoxide and carbon dioxide at an elevated temperature and pressure to a methanol converter reactor containing one or more beds of a methanol synthesis catalyst such as a copper and zinc oxide catalyst. The carbon monoxide and carbon dioxide in the synthesis gas react with the hydrogen to form methanol across the catalyst. The methanol synthesis process is usually operated in a loop where a portion of the compressed synthesis gas is converted to methanol each pass through the methanol converter reactor. Methanol product is recovered by cooling the methanol product gas stream to a temperature below the dew point of the methanol such that crude methanol and water condense out, with the remaining gas being recycled through the methanol converter reactor. The crude methanol and water produced in the methanol converter reactor are typically reduced in pressure in a let-down or "flash" vessel. Since most crude methanol contains a large range of impurities, the crude methanol must be purified so as to remove such impurities to produce methanol of chemical grade quality. The preferred technique used for methanol purification is a distillation process.
Synthesis gas is typically characterized by the stoichiometric ratio (H2—CO2)/(CO+CO2), often referred to as the module. A module of about 2.0 defines the desired stoichiometric ratio of synthesis gas for the production of methanol. A synthesis gas with a module less than about 2.0 signifies that the synthesis gas is deficient in hydrogen for the production of methanol. In such a case, the hydrogen will be consumed in the methanol synthesis reaction while a substantial portion of the carbon monoxide and carbon dioxide remain unreacted leading to a recycle stream of unreacted gas which has high levels of carbon monoxide and carbon dioxide but is low in hydrogen. This causes several disadvantages including higher volume of catalysts and increased production of unwanted by-products, namely higher alcohols and ketones. The module of crude synthesis gas is often determined by the reforming process used. Reforming processes such as partial oxidation (POx) and autothermal reforming (ATR) generally producing hydrogen deficient synthesis gas.
To remedy the hydrogen deficiency of synthesis gas, it has been suggested to recover hydrogen from the purge stream using a hydrogen recovery unit such as a hydrogen pressure swing adsorption (PSA) unit or hydrogen separation membrane. The recovered hydrogen is recycled back into the synthesis gas so that the gas within the methanol synthesis loop is significantly more hydrogen rich than the originally produced synthesis gas. An alternative method to remedy the hydrogen deficiency of synthesis gas is to take a side-stream of the original produced synthesis gas and recover hydrogen from it using a hydrogen pressure swing adsorption (PSA) unit or hydrogen separation membrane and feeding the recovered hydrogen back into the synthesis gas directed to the methanol synthesis reactor. See U.S. Pat. Nos. 7,786,180; 7,470,811; and 4,650,814. U.S. Pat. No. 7,786,180 likely represents the closest prior art in the field of methanol synthesis where hydrogen is recovered using a hydrogen recovery unit from both the purge gas and a portion of the original synthesis gas or make up gas. The recovered hydrogen is simply added to the synthesis gas mixture that is directed to the methanol synthesis reactor.
However, the above-identified solutions are limited to addressing the hydrogen deficiency of synthesis gas with conventional reforming processes such as steam methane reforming (SMR), partial oxidation (POx), autothermal reforming (ATR) or combinations thereof. The present invention proposes a method for adjusting the synthesis gas module using a reactively-driven oxygen transport membrane based system coupled with a heated pre-reformer.
Specifically, the improvements to the reactively-driven oxygen transport membrane based system include modifications to the reactively-driven oxygen transport membrane based system to carry out both a primary reforming process in a catalyst filled reforming reactor as well as a secondary reforming process within the catalyst containing oxygen transport membrane reactor.
Additional improvements to the reactively-driven oxygen transport membrane based system include modifications to the steam and hydrocarbon feed stream and downstream conditioning of the synthesis gas. In addition, using a reactively driven oxygen transport membrane reactor with hydrogen and carbon-monoxide as a portion of the feed produces a higher oxygen flux compared to reactively-driven oxygen transport membranes that use only steam-methane feed. The actual difference in flux performance is a function of pressure, temperature, and reactant gas concentrations. Finally, some modifications or changes are proposed to the heat recovery train to mitigate metal dusting and carbon formation issues that adversely impact system performance, reliability and durability of the system.

Method and system for adjusting synthesis gas module in an oxygen transport membrane based reforming system


Disclosed is a Co/Al2O3/SiC catalyst for Fischer-Tropsch synthesis exhibiting superior heat transfer and mass transport effects, wherein an Al2O3/SiC support in which alumina is coated on silicon carbide (SiC) with superior thermal conductivity is used and cobalt (Co) is supported thereon as an active component to provide a bimodal pore size distribution, and a method for preparing same. Use of the Al2O3/SiC support improves cobalt dispersion and enhances cobalt-support interaction, thereby inhibiting generation of cokes (carbon filaments). As a result, catalyst stability is improved and conversion of syngas (carbon monoxide and hydrogen) can be improved.

(a) Technical Field
The present invention relates to a catalyst for Fischer-Tropsch synthesis (FTS), a method for preparing same and a method for preparing liquid hydrocarbons from a syngas using same.
(b) Background Art
In general, cobalt-based catalysts are mainly used in preparation of liquid hydrocarbons from a syngas through Fischer-Tropsch synthesis (FTS). The cobalt-based catalyst is known to have high carbon monoxide conversion, long life and superior hydrocarbon selectivity due to low CO2 production rate. However, because the cobalt-based catalyst favors production of methane predominantly at high temperatures of 300° C. or above, design of the catalyst for control of local temperature increase using a catalyst-bed is of importance. Due to this problem and in terms of cost reduction and enhancement of activity, a support having thermally and chemically stable pores and having a large surface area such as alumina, silica, titania, etc. is used and an active component is dispersed thereon, although heat transfer effect is lower.
According to the Anderson-Schulz-Flory (ASF) distribution, straight-chain hydrocarbons are mainly produced by the FTS reaction. In case of high-boiling-point hydrocarbons, carbon deposition may be predominant at hot spots over product desorption, thereby quickly deactivating the catalyst [Chemical Reviews 107 (2007) 1692]. Accordingly, in order to enhance dispersion of the active component of cobalt and to inhibit carbon deposition, a support having a large surface area, such as alumina, silica or titania described above, is often surface-treated to improve catalytic activity by controlling the particle size of supported cobalt [Journal of American Chemical Society, 128 (2006) 3956]. As an example of such support surface treatment, a method of inhibiting carbon deposition on the surface of a catalyst prepared using a silica-alumina support having a bimodal pore size distribution by enhancing the speed of transportation of high-boiling-point hydrocarbons produced during the FTS reaction is reported [US Patent Application Publication No. 2005/0107479 A1].
Meanwhile, a method of modifying the surface of a silica support using an enhancer such as zirconium in order to enhance reducibility of cobalt and improve selectivity for high-boiling-point hydrocarbons by inhibiting adsorption of FTS products is also reported [Journal of Catalysis, 185 (1999) 120].
As for methods of performing the FTS reaction using silicon carbide (SiC) as a support, it is reported that a superior catalytic activity is achieved when the FTS reaction is performed using a SiC support having superior heat transfer effect prepared by mixing with an inorganic material (e.g., silica sol) and using cobalt as an active component [U.S. Pat. No. 5,710,093]. It is also reported that a cobalt-based FTS catalyst prepared by coating an alumina sol on a silicon carbide foam having mesopores has superior catalytic activity because of improved mass transport effect owing to the large-sized pores of the silicon carbide foam [Applied Catalysis A: General, 397 (2011) 62]. All of these preceding researches use cobalt-based catalysts prepared by using the silicon carbide support having superior heat transfer property and enhancement of catalyst stability through improved cobalt dispersion and controlled metal-support interaction between the cobalt active component and the alumina support or improvement of catalytic activity through introduction of a bimodal pore size distribution and a method for preparing such a catalyst have not been presented yet.
The present invention aims at presenting a method for inhibiting deactivation of a catalyst using a silicon carbide support caused by deposition of hydrocarbon compounds by maximizing heat transfer effect and thus controlling hot spots as well as a method for preparing a support having a bimodal pore size distribution by controlling the pores of an alumina-coated silicon carbide support and thereby improving catalytic activity through enhanced cobalt dispersion and ensuring long-term catalyst stability through controlled interaction between cobalt and the support.
Throughout the specification, a number of publications and patent documents are referred to and cited. The disclosure of the cited publications and patent documents is incorporated herein by reference in its entirety to more clearly describe the state of the related art and the present invention.

Catalysts for synthesis of liquid hydrocarbons using syngas and preparation methods thereof

KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY