Mary Y Chen

US Patent:

45230269, Jun 11, 1985

Filed:

Aug 26, 1983

Appl. No.:

6/526581

Inventors:

K. Ming Wan - East Brunswick NJ
Mary S. Chen - Edison NJ
Anil D. Pendse - Highland Park NJ

Assignee:

Hatco Chemical Corporation - Fords NJ

International Classification:

C07C125065

US Classification:

560163

Abstract:

N-Benzyloxycarbonyl-L-aspartic acid (Z-Asp) is synthesized by adding benzyl chloroformate to a solution of L-aspartic acid and sodium hydroxide at relatively high temperatures of 35. degree. -55. degree. C. and over a wide pH range of 9. 2-12. 0 and acidifying the sodium salt product. The Z-Asp is prepared in high yields exceeding 90% and purity of better than 99% with only a minor amount of the by-product N-benzyloxycarbonyl aspartyl aspartic acid. The Z-Asp is suitable for conversion to aspartame. Carrying out the reaction at high temperatures significantly reduces cycle time while maintaining a high yield with a low dipeptide and unreacted L-aspartic acid content.

US Patent:

45187924, May 21, 1985

Filed:

Aug 26, 1983

Appl. No.:

6/526579

Inventors:

Clay T. Chen - Edison NJ
K. Ming Wan - East Brunswick NJ
Mary S. Chen - Edison NJ

Assignee:

Hatco Chemical Corporation - Fords NJ

International Classification:

C07C125065

US Classification:

560163

Abstract:

N-Benzyloxycarbonyl-L-aspartic acid (Z-Asp) is synthesized by adding benzyl chloroformate to a solution of L-aspartic acid and sodium hydroxide at temperatures from about 5. degree. -55. degree. C. and over a wide pH range of about 9. 2 to 13. 8 in the presence of a surfactant and/or a buffer and then acidifying the reaction mixture. Carrying out the reaction in the presence of a surfactant reduces cycle time, while maintaining a high yield with low by-product content. The buffer prevents wide fluctuations in pH and minimizes localized reaction. These conditions are desirable when the reaction rate has been increased by addition of a surfactant or an increase in temperature of the reaction mixture.

US Patent:

55282091, Jun 18, 1996

Filed:

Apr 27, 1995

Appl. No.:

8/430067

Inventors:

Perry A. Macdonald - Culver City CA
Lawrence E. Larson - Bethesda MD
Michael G. Case - Thousand Oaks CA
Mehran Matloubian - Encino CA
Mary Y. Chen - Agoura CA
David B. Rensch - Thousand Oaks CA

Assignee:

Hughes Aircraft Company - Los Angeles CA

International Classification:

H01P 500
H01P 308

US Classification:

333247

Abstract:

A monolithic microwave integrated circuit is formed by positioning a distributed, transmission-line network over a microwave-device structure. The ground plane of the transmission-line network adjoins an interconnect system of the microwave-device structure and signal lines of the transmission-line network are adapted to communicate with the microwave-device structure through orifices of the ground plane. The invention facilitates the use of low-cost silicon-based transistors in monolithic microwave integrated circuits.

US Patent:

45700150, Feb 11, 1986

Filed:

Aug 26, 1983

Appl. No.:

6/526580

Inventors:

K. Ming Wan - East Brunswick NJ
Mary S. Chen - Edison NJ
Clay T. Chen - Edison NJ

Assignee:

Hatco Chemical Corporation - Fords NJ

International Classification:

C07C12506

US Classification:

560163

Abstract:

N-Benzyloxycarbonyl-L-aspartic acid (Z-Asp) crystals several times larger than those obtained by conventional crystallization are prepared by acidifying an alkaline aqueous solution of a metal salt of Z-Asp at high temperatures of between about 20. degree. to 45. degree. C. The resulting large crystals contain less moisture and less impurities such as sodium chloride, dipeptide and benzyl alcohol, etc. than those crystals obtained at lower temperatures and they are easily processed for preparing aspartame.

US Patent:

51498677, Sep 22, 1992

Filed:

Jul 28, 1987

Appl. No.:

7/078550

Inventors:

Clay T. Chen - Metuchen NJ
Mary S. Chen - Metuchen NJ

Assignee:

Hatco Corporation - Fords NJ

International Classification:

C07C 5142

US Classification:

562486

Abstract:

The invention makes available an improved process for the crystallization and purification of a water-insoluble aromatic dicarboxylic acid, such as 2,6-naphthalenedicarboxylic acid. The process involves steps of contacting the insoluble acid with aqueous base to make a water-soluble di salt of the acid, removal of insoluble impurities to obtain a clear solution of the di salt, partial acidification of the solution by adding a water-soluble acid, holding the thus-obtained slurry of the insoluble acid and its salt for a time sufficient to allow dissolution of the initially-formed small particles of the insoluble acid and the formation of large well-formed crystals, then acidifying the slurry further to convert remaining salts to the insoluble acid, and recovering this acid. The crystallization can be accelerated by recycling product and by adding surfactants, and can be operated in a continuous mode. 2,6-Naphthalenedicarboxylic acid thus crystallized is readily dried, non-sticky, non-dusty, and of high purity.

US Patent:

20150349117, Dec 3, 2015

Filed:

May 29, 2014

Appl. No.:

14/290029

Inventors:

- Malibu CA, US
Mary Y. Chen - Beverly Hills CA, US
Xu Chen - Los Angeles CA, US
Zijian "Ray" Li - Oak Park CA, US
Karim S. Boutros - Moorpark CA, US

International Classification:

H01L 29/78
H01L 29/66
H01L 29/20

Abstract:

A field-effect transistor (FET) includes a plurality of semiconductor layers, a source electrode and a drain electrode contacting one of the semiconductor layers, a first dielectric layer on a portion of a top semiconductor surface between the source and drain electrodes, a first trench extending through the first dielectric layer and having a bottom located on a top surface or within one of the semiconductor layers, a second dielectric layer lining the first trench and covering a portion of the first dielectric layer, a third dielectric layer over the semiconductor layers, the first dielectric layer, and the second dielectric layer, a second trench extending through the third dielectric layer and having a bottom located in the first trench on the second dielectric layer and extending over a portion of the second dielectric, and a gate electrode filling the second trench.