摘要:
There is disclosed a process for the hydration of an acid selected from the group consisting of maleic acid, fumaric acid, sodium hydrogen maleate and mixtures thereof to malic acid in an aqueous reaction mixture in excellent yields and with particularly high purity by performing the synthesis in the presence of sodium ions in the molar ratio of sodium ions to acid or salt thereof in the range of from 0.2 to about 0.5.
摘要:
There is disclosed herein an improved processes for the preparation of oxydisuccinate by reacting in an alkaline reaction medium the salts of maleic acid and malic acid in the presence of a calcium ion catalyst wherein unreacted maleic acid salts are recovered from the reaction medium as sodium hydrogen maleate by lowering the pH of the reaction product to a range of from about 4 to 6. The precipitated sodium hydrogen maleate salts are recycled to the synthesis reaction as salts of malic acid by hydration in the presence of a hydration catalyst to prepare additional amounts of product.
摘要:
A conventional golf club head is releasably connected to a golf club shaft through operation of a wedge on the lower end of a rod in the shaft moveable in and out of the lower end of the shaft to releasably cause the shaft side wall to create a friction fit in the hollow club head shank. A nut on the rod at the upper end of the shaft covered by a cap allows for rotation of the rod to advance or retract the wedge in the lower end of the shaft.
摘要:
Iodine is employed as a promoter for the reaction between phenol and a 1,2-dihaloethane wherein the halogen is chlorine, bromine or iodine using a zinc-containing catalyst to produce dihydroxydiphenylethanes, especially the 4,4'-isomer.
摘要:
The invention is essentially a motherboard design for personal computers which uses DSP hardware in conjunction with a general or specific purpose CPU to process command and continuous speech. The DSP hardware serves as a bridge between the audio input of the sound card or integrated sound module and the microprocessor. The DSP chip itself can serve as a processor and embedded speech engine for processing command and control speech. It can also serve as a pre-processor for continuous speech, converting the digital bit stream representing the speech to phonemes for processing by the CPU and software-based speech engine and can facilitate digital mobile phone functions and text to speech conversion.
摘要:
This invention involves a process for the carbonylation of a carbonylatable reactant, e.g., an alkyl ester, a dialkyl ether or mixtures thereof by reacting the same with carbon monoxide. The process comprises effecting the carbonylation in the presence of a solution of a catalyst system containing a rhodium compound, an iodide and a lithium component at a temperature of from 50.degree. C. to 400.degree. C. at a carbon monoxide partial pressure of 1 psig to 15,000 psig. Hydrogen may also be present. The invention also concerns a carbonylation catalyst system effective for the addition of carbon monoxide to a carbonylatable reactant which comprises a solution containing as essential components a rhodium containing active component, an iodide and a lithium component.
摘要:
A cable meter for monitoring the channel selected by a converter of a television system which receives signals by means of cable. The cable is connected to the cable meter and the output of the cable meter is applied to the converter. The output of the converter is connected back to the cable meter which, in turn, provides an output to the television. During normal operation, signals received by the cable meter from the cable pass directly to the converter, and a selected channel from the converter passes through the cable meter to the television. To monitor the channel selected, an oscillator generates a substitution signal which is substituted for the television signal applied to the converter. The cable meter then monitors whether the substitution signal passes through the converter, during which period, the cable meter prohibits this substitution signal from reaching the television. By varying the frequency of the substitution signal, a search is performed for the selected channel. Techniques are employed to enhance the accuracy of the monitoring. The present invention has applicability to any communications system in which radio frequency signals are transmitted over any medium, such as televisions with internal tuners which may not even be adapted to receive cable signals or radio receivers.
摘要:
This invention provides a single unit called a personal communicator that combines the functions of a cell phone (or mobile phone), a body-supported computer and a pager. The personal communicator has three detachable modules: 1. a communications module; 2. a display module; and 3. a core computer module The core computer module has all of the components of a general purpose computer. Each of the modules when detached can be used in other systems such as with larger screens.
摘要:
A modular valve assembly of this invention includes individual valve units and components, which can be selectively combined to form an integrated multi-port, multi-way valve assembly that is operated by a single common linear actuator is disclosed. The modular design of this invention is facilitated by the construction of valve housings and valve components of the individual valve units and assemblies of common plumbing pipes and fittings, such as, tee joints, threaded couplings, bushings and reducers. A single linear actuator, such as a conventional solenoid or piston cylinder mounted to the end of the valve housing, reciprocates an elongated shaft running axially through the valve interior to move various valve discs into and out of engagement with various internal valve seats, thereby controlling the valve assembly operation.
摘要:
Alkylidene diesters such as ethylidene diacetate are produced by reacting an ether and/or an ester under substantially anhydrous conditions with carbon monoxide and hydrogen in contact with a catalyst system comprising a rhodium compound and a halogen component at a temperature in the range from 125.degree. to 300.degree. C. and at a carbon monoxide partial pressure in the range from about 1.0 to 1100 kg/cm.sup.2. When ethylidene diacetate is the product, it can then be decomposed to produce vinyl acetate and acetic acid by well-known techniques. Since one mole of acetic acid is also produced in the synthesis of the diacetate, the invention makes possible an overall process for the production of vinyl acetate which produces acetic acid rather than consumes it.