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Synthesis of a new hydroxyethylene dipeptide isostere Phe ψ[CH2CH(OH)]Phe as HIV-1 protease inhibitor

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Acta Pharmacologica Sinica 1994年第1期15卷 34-36页

作者： Huai Gu CHEN, Tomi K SAWYER, Peter G M WUTS (Upjohn laboratories, Process Research and Development, The Upjohn Company, Kalamazoo MI 49001, USA) Parke-Davis Pharmaceutical Research Division,Warner-Lambert Co.2800 Plymouth Road,Ann Arbor MI 48105 USA. Upjohn laboratories Upjohn Company Kalamazoo MI 49001.

A new type of pseudodipeptide isostere exampled by Phe ψ[CH2CH(OH)]Phe was synthesized from phenylalanine. The H]V protease inhibitory activity (IC50) of Noa-His-Pheψ[CH2CH(OH)]Phe-Ile-Amp was 0. 8 pmol·L-1.

关键词： dipeptides HIV protease inhibitors structure-activity relationship

Comparative studies on Y(Ⅲ)and Dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of Rare Earths 2018年第12期36卷 1342-1350页

作者： N.E.El-Hefny M.S.Gasser Sh.Sh.Emam W.H.Mahmoud H.F.Aly Hot laboratories Centre Atomic Energy Authority Faculty of Science Ain Shams University

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [MA·(HA)] for Y(III) or Dy(III) in both media.1.0 mol/L HCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both HCI and HNOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides Separation factor Saponification

Catalytic transfer hydrogenolysis as an efficient route in cleavage of lignin and model compounds

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Green Energy & Environment 2018年第4期3卷 328-334页

作者： Jiaguang Zhang School of Chemistry University of Lincoln Joseph Banks Laboratories

Cleavage of aromatic ether bonds through hydrogenolysis is one of the most promising routes for depolymerisation and transformation of lignin into value-added chemicals. Instead of using pressurized hydrogen gas as hydrogen source, some reductive organic molecules, such as methanol, ethanol, isopropanol as well as formates and formic acid, can serve as hydrogen donor is the process called catalytic transfer hydrogenolysis. This is an emerging and promising research field but there are very few reports. In this paper, a comprehensive review of the works is presented on catalytic transfer hydrogenolysis of lignin and lignin model compounds aiming to breakdown the aromatic ethers including a-O-4, b-O-4 and 4-O-5 linkages, with focus on reaction mechanisms. The works are organised regarding to different hydrogen donors used, to gain an in-depth understanding of the special role of various hydrogen donors in this process. Perspectives on current challenges and opportunities of future research to develop catalytic transfer hydrogenolysis as a competitive and unique strategy for lignin valorisation are also provided.

关键词： Catalytic transfer hydrogenolysis Heterogeneous catalysis Lignin Hydrogen donor Aromatic ether bonds

Monitoring of PON System Using Compound Surveillance Technique

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Journal of Electronic Science and Technology 2015年第2期13卷 169-173页

作者： Sun-Chien Ko Hsiu-Jung Chuang Si-Chong Chen Chih-Yih Wang Sheng-Fwu Lin Telecommunication laboratories Chunghwa Telecom Co.Ltd.

A passive optical network（PON） monitoring system combined light pulse and frequency sweep techniques is proposed and verified in a field test. The light pulse surveys over the all whole network and the frequency sweep are used to investigate any fault in the link. The field test is performed with 4 PONs. Each PON is monitored at 4 ports, one is the splitter port and the other three are arbitrary chosen multiple optical units（ONUs）. All the tested PONs are monitored in turns once per hour. Faults at the feeder and branch fiber have been observed in this field test and have been analyzed with the monitoring system.

关键词： verified arbitrary monitored splitter branch chosen reflective turns restoration realistic

A NEW METHOD FOR EXTENDING THE OPERATION FREQUENCY BANDWIDTH OF CORRUGATED HORNS BY USING THE NEGATIVE ADMITTANCE REGION

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Journal of Electronics(China) 1986年第3期3卷 238-241页

作者：陈木华 Shijiazhuang Communication laboratories

A new method is presented for extending the operation frequency bandwidth of corrugated hornsby making use of the negative admittance *** concept is verified by experimental results.

关键词： mode HE A NEW METHOD FOR EXTENDING THE OPERATION FREQUENCY BANDWIDTH OF CORRUGATED HORNS BY USING THE NEGATIVE ADMITTANCE REGION line

THE MODE TRANSFORMATION AND THE RADIATION PATTERN OF THE DIELECTRIC-LOADED HORN

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Journal of Electronics(China) 1985年第4期2卷 329-333页

作者：章日荣刘顺祥周康健 Shijiazhuang Communication laboratories

In this paper,the boundary condition characteristic equation of the dielectric-loaded guide andthe characteristic values of the hybrid modes in it are *** mode transformation equationsbetween the dielectric-loaded guide and a general waveguide are also *** the computed radiation patterns of the dielectric-loaded horn made by Yang Shihua(1977)are *** predicted and the measured radiation patterns superimpose each other satis-factorily.

关键词： mode THE MODE TRANSFORMATION AND THE RADIATION PATTERN OF THE DIELECTRIC-LOADED HORN

A rapid and sensitive liquid chromatography-tandem mass spectrometric assay for duloxetine in human plasma:Its pharmacokinetic application

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Journal of Pharmaceutical Analysis 2013年第1期3卷 36-44页

作者： Ramakrishna Gajula Rambabu Maddela Vasu Babu Ravi Jaswanth Kumar Inamadugu Nageswara Rao Pilli Wellquest Clinical Research laboratories

This paper describes a simple, rapid and sensitive liquid chromatography tandem mass spectrometry assay for the determination of duloxetine in human plasma. A duloxetine stable labeled isotope （duloxetine ds） was used as an internal standard. Analyte and the internal standard were extracted from 100 btL of human plasma via solid phase extraction technique using Oasis HLB cartridges. The chromatographic separation was achieved on a Cl8 column by using a mixture of acetonitrile 5 mM ammonium acetate buffer （83：17, v/v） as the mobile phase at a flow rate of 0.9 mL/min. The calibration curve obtained was linear （r2≥0.99） over the concentration range of 0.05 101 ng/mL. Multiple-reaction monitoring mode （MRM） was used for quantification of ion transitions at rn/z 298.3/154.1 and 303.3/159.1 for the drug and the internal standard, respectively. Method validation was performed as per FDA guidelines and the results met the acceptance criteria. A run time of 2.5 min for each sample made it possible to analyze more than 300 plasma samples per day. The proposed method was found to be applicable to clinical studies.

关键词： Duloxetine in humanplasma Solid-phase extraction(SPE) Liquidchromatography-tandem mass spectro-metry Method validation Pharmacokinetic studies

ANALYSIS OF N-SLOT STRUCTURE CORRUGATED HORN

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Journal of Electronics(China) 1990年第1期7卷 22-29页

作者：杜彪章日荣王汉礼杜树祥 Shuijiazhuang Communication laboratories Shijiazhuang

On the space harmonics technique general formulas are derived of the characteristicequation and the equivalent wall admittance of corrugated horns with N-slot structure(each periodhas N slots whose shape and depth may be the same or different).As an example,the calculatedradiation patterns for a corrugated horn having dual-depth corrugations show good agreementwith the measured ones.

关键词： Antenna Corrugated horn

Nonlinear polarization effects and mitigation in polarization-division-multiplexed coherent transmission systems

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Chinese Optics Letters 2010年第9期8卷 844-851页

作者：谢崇进 Bell laboratories Alcatel-Lucent 791 Holmdel-Keyport Road Holmdel NJ 07733 USA

Using numerical simulations, the nonlinear transmission performance of polarization-division-multiplexed quadrature-phase-shift-keying （PDM-QPSK） coherent systems is studied. It is found that inter-channel cross-polarization modulation （XPolM） induced nonlinear polarization scattering can significantly degrade the transmission performance of PDM-QPSK coherent systems and change the perspective of dispersion management in optical coherent transmission systems. Some techniques to mitigate nonlinear polarization scattering in dispersion-managed PDM coherent transmission systems are discussed, including the use of time-interleaved return-to-zero （RZ） PDM formats, the use of periodic-group-delay PGD dispersion compensators, and the judicious addition of some polarization-mode-dispersion （PMD） in the transmission link. It is shown that if nonlinear polarization scattering can be well mitigated, a polarization multiplexed optical coherent transmission system with dispersion management could perform better than that without it.

关键词： QPSK NRZ Nonlinear polarization effects and mitigation in polarization-division-multiplexed coherent transmission systems PDM WDM PGD