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Chemical Research in Chinese Universities 2019年第5期35卷 788-791页

作者： MO Lixin ZHAO Hengxin MA zheng YU Wenxiao Huihua College Hebei Normal UniversityShijiazhuang 050091P.R.China Center for Evaluation and Facility Developnent Hebei University of Economics and BusinessShijiazhuang 050061P.R.China

Gold nanoclusters(AuNCs) were prepared in the presence of the nucleobases of poly-cytosine DNAs in this paper. We have demonstrated tliat the fluorescence of the AuNCs is quenched by thiocyanate(SCN^-) through the interaction between SCN^- and gold atoms. AuNCs can receive energy from nucleobases to boost their emission intensity, while in the presence of SCN^-, they coordinate with Au atoms and influence the energy transfer between the nucleobases and AuNCs, leading to the fluorescence quenching. The decreased fluorescence intensity was in proportion to the concentration of SCN^- in the range of 8.0×10^-7-1.5×10^-5 mol/L with a limit of detection of 4.2×10^-7 mol/L(3σ). We further validated the practice of this probe througli the detection of SCbT in natural water samples.

关键词： Fluorescence Thiocyanate Gold nanocluster

A Facile Procedure for Conjugate Addition of Amines to Electron Deficient Alkenes with Metal Oxide as Catalyst

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Chemical Research in Chinese Universities 2009年第5期25卷 744-747页

作者： LIANG Xue-zheng GAO Shan YANG Jian-guo Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062 P. R. China Energy Institute Department of Materials Science and Engineering Pennsylvania State University PA 16802 USA

A novel efficient procedure has been developed for the conjugate addition of amines to electron deficient alkenes. A series of metal oxides was synthesized for catalyzing the conjugate addition of amines and alkenes. After optimizing the reaction conditions, SrO was chosen as the most efficient catalyst for the reactions. The results show that the catalyst is very efficient for the conjugate addition of amines to electron deficient alkenes with the excellent yields in several minutes. Operational simplicity, without need of any solvent, low cost of the catalyst used, high yields, reusability, excellent chemoselectivity and applicability to large-scale reactions are the key features of this methodology.

关键词： Heterogeneous Conjugate addition Chemoselective Metal oxide Solvent-free

Template Polymerization Based on Stober Method:an Improved Method for Fabrication of Hollow Polysiloxane Spheres

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Chinese Chemical Letters 2006年第5期17卷 637-640页

作者： Hui Gang WANG Ping CHEN Xiao Ming zheng Department of Chemistry Zhejiang Sci-Tech University Hangzhou 310018 Department of Chemistry Zhejiang University Hangzhou 310028

A modified Stober method has been developed which permits the controlled growth of spherical hollow spheres with diameters between 197 and 208 nanometers by consecutively cocondensed methyltrimethoxysilane and dimethyldimethoxysilane monomers onto microemulsion of polydimethylsiloxane and subsequently removing the templated polydimethylsiloxane by exposure to solvents. Ammonia was used as a morphological catalyst. The morphology of the polymer spheres was demonstrated by transmission electron micrographs （TEM） and atomic force microscopy （AFM）.

关键词： Stober method hollow polysiloxane spheres template polymerization.

Synthesis of 2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide, A New Potential Antitumor Phosphorus Heterocycle Compound

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Chinese Chemical Letters 2000年第8期11卷 665-666页

作者： Xu, L zheng, GR Xia, M Cai, JC Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide 8, phosphorus counterpart of 2, 6-dioxopiperazine, was synthesized as antitumor agent. The new phosphorus heterocycle compound 8 is the key intermediate in the synthe... 详细信息

关键词： antitumor activity phosphorus heterocycle compound 2,6-dioxopiperazine

Influence of Rapid Thermal Annealing on Structural and Interfacial Properties of Lead-Zirconate-Titanate Thin Films Prepared by Excimer Laser Deposition

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Chinese Physics Letters 1994年第8期11卷 518-521页

作者： zheng Lirong CHEN Yiqing LIN Chenglu ZOU Shichang State Key Laboratory of Functional Materials for Informatics Shanghai Institute of MetallurgyAcademia SinicaShanghai 200050

Lead zirconate titanate thin films were prepared by pulsed excimer laser deposition on silicon *** thermal annealing was used to improve its *** and interfacial characteristics of the films before and after annealing ... 详细信息

关键词： properties resistance annealing

Determination of 19 polyphenolic compounds in tea by ultra-high performance liquid chromatography combined with quadrupole-time of flight mass spectrometry

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Food Science and Human Wellness 2022年第3期11卷 719-726页

作者： Jian Li Junmei Ma Yan Zhang Lei zheng School of Food and Biological Engineering Hefei University of TechnologyHefei 230009China College of Applied Arts and Science Beijing Union UniversityBeijing 100191China Hebei Key Laboratory of Forensic Medicine College of Forensic MedicineHebei Medical UniversityShijiazhuang 050017China Hebei Food Safety Key Laboratory Hebei Food Inspection and Research InstituteShijiazhuang 050227China

A rapid method was presented for the determination of 19 polyphenols in tea by ultra-high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF MS).Tea samples were extracted by 50%(V/V)ethanol,then separated by Waters Acquity BEH C18 column using a binary solvent system composed of acetonitrile and water(0.1%formic acid)by gradient *** analytes were determined by Q-TOF MS in TOF MS and information dependent acquisition(IDA)-MS/MS *** results showed that mass accuracy error of the 19 polyphenols were lower than 5.0×10^(-6),good linear relationship was got in range of 0.2–500μg/L and correlation coefficient was higher than *** LOD was in the range of 0.002–0.100 mg/kg and the LOQ was in the range of 0.004–0.200 mg/*** of the method was in range of 78.4%–109.2%with spike levels of 0.004–2.000 mg/kg,relative standard deviations were lower than 10%.The method was simple,rapid and *** could be used for the rapid screening and quantitative analysis of 19 polyphenols in tea.

关键词： Ultra-high performance liquid chromatography Quadrupole-time of flight mass spectrometry Tea Polyphenols

Current strategies for preventing the recurrence of hepatocellular carcinoma after liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2015年第2期14卷 145-149页

作者： Zhuo-Yi Wang Lei Geng Shu-Sen zheng Key Laboratory of Combined Multi-organ Transplantation Ministry of Public Health Division of Hepatobiliary and Pancreatic Surgery First Affiliated Hospital Zhejiang University School of Medicine Division of Hepatobiliary and Pancreatic Surgery First Affiliated Hospital Zhejiang University School of Medicine

BACKGROUND：Liver transplantation is the optimal treatment for a selected group of patients with moderate to severe cirrhosis and hepatocellular carcinoma（HCC）.Despite the strict selection of candidates,post-transplant recurrence often occurs and markedly reduces the long-term survival of patients with *** present review focuses on the current strategies on preventing the recurrence of HCC after liver *** SOURCES： Relevant articles were identified by exten- sive searching of PubMed using the keywords ＂hepatocellular carcinoma＂, ＂recurrence＂ and ＂liver transplantation＂ between January 1996 and January 2014. Additional papers were searched manually from the references in key articles. RESULTS： The current theories of HCC recurrence after liver transplantation are：（i） the growth of pre-transplant occult metastases; （ii） the engraftment of circulating tumor cells released at the time of transplantation. Pre-transplant treatment aims to control local tumor by radiofrequency ablation, transarterial embolization and transarterial chemoembolization. The main objective during the operation is to prevent tumor cell dissemination. Post-transplant treatment includes systemic anticancer therapy, antiviral therapy, and most recently, immunotherapy. These strategies concentrate on the control of the tumor when the patients are waiting for transplant, to reduce the release of HCC cells during surgical procedures and to dear the occult HCC cells after ***： Much can be done to prevent HCC recurrence after liver transplantation. In future, effort is likely to be di- rected towards combining multidisciplinary approaches and various treatment modalities.

关键词： hepatocellular carcinoma recurrence liver transplantation

SEGREGATION EFFECT ON SURFACE COMPOSITION IN ALLOY SPUTTERING

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Chinese Physics Letters 1990年第3期7卷 140-143页

作者： zheng Liping LI Risheng LI Mingyao CUI Fuzhai Shanghai Institute of Nuclear Research Academia SinicaP.O.Box 8204Shanghai201800 Institute of Metal Research Academia SinicaShenyang110015 Department of Engineering Physics Tsinghua UniversityBeijing100084

The modified dynamic TCIS(Transport and atomic Collision cascade of energetic Ions an Solids)Monte Carlo program including the radiation-enhanced Gibbsian segregation(REGS)is employed to estimate the compositional distributions at surface of the Au_(0.56)Cu_(0.44) alloy under 2keV Ar^(+) ion bombardment at high *** calculation results exhibit that the Au composition enriches in the first layer(74 at.%),depletes in the second layer(37 at.%)and gradually rises with depth to the bulk *** effect of the relation between sputter depth and segregation layer on the surface concentration of Au_(0.56)Cu_(0.44) is also discussed.

关键词： alloy layer SURFACE

Power optimization and performance improvement for embedded Ethernet SOC

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 102-106页

作者： zheng Zhao-xia ZOU Lian-ying GAO Jun Research Center for VLSI and Systems Huazhong University of Science andTechnology Wuhan 430074 China School of Electric and information Engineering Wuhan Institute ofTechnology Wuhan 430074 China

Information appliance is the combination of traditional home appliances and the internet technology. In this article, an Ethernet controller system-on-chip （SOC） solution for information appliances is presented. To achieve high performance, the embedded 8 bits 8051 micro control unit （MCU） is optimized by an independent instruction bus and a data bus. Besides, a two-stage pipeline feature is added. Compared with the existing 8051 core, the enhanced one-cycle MCU offers ten times improvement in instruction execution efficiency. Meanwhile, the performance of media access control （MAC） circuit is greatly improved by adopting various techniques such as direct memory access （DMA） control, paging strategy, etc. To reduce the power consumption, clock gating, low power supply, and multi-working-clock are adopted. Moreover, to achieve rapid data communication in different clock frequency circuits, a simple ping-pong first in first out （FIFO） circuit is realized. The chip is implemented using TSMC 0.25 μm two-poly four-metal mixed signal complementary metal oxide semiconductor （CMOS） technology. Its die area is 4.8 min× 4.6 mm. The test results show that the maximum throughput of Ethernet packets can reach 7 Mb/s while the power consumption is rather low-the working current is just about 200 mA.

关键词： low power technology hardware/software co-design,circular buffer throughput

Controlled Growth and Cathodoluminescence Property of ZnS nanobelts with Large Aspect Ratio

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Nano-Micro Letters 2010年第4期2卷 272-276页

作者： Xiang Wu Ying Lei Yufeng zheng Fengyu Qu College of Chemistry and Chemical Engineering Harbin Normal University Center for Biomedical Materials and Engineering Harbin Engineering University

ZnS nanobelts with large aspect ratio are successfully synthesized on a large scale through thermally evaporating of ZnS powder with a trace of SnO_2 powder using gold coated Si wafer as the substrate at 1100°*** results indicate that the as-obtained ZnS nanobelts are about 10 nm in thickness and hundreds of micrometers in length,and the aspect ratio reaches more than *** dependent experiments are conducted to better study the growth mechanism of the ZnS ***,optical properties of the as-synthesized ZnS nanobelts are also investigated by using a cathodoluminescence(CL) system,which shows the existence of a strong ultraviolet emission at 342 nm and two poor emission peaks at 522 nm and 683 nm at room temperature,respectively.

关键词： Semiconductor ZnS Nanobelts Cathodoluminescence