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New anthraquinone derivatives from the roots of Berchemia floribunda

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Chinese Chemical Letters 2007年第4期18卷 412-414页

作者： xin Wei Jian Shuang Jiang Zi Ming Feng Pei Cheng zhang Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine （Ministry of Education） Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beifing 100050 China

A new naphthoquinone-anthraquinone dimer named floribundiquinone E （1） and a new anthraquinone 2-acetylphyscion （2） were isolated from the roots of Berchemia floribunda Brongn. Their structures were elucidated on ... 详细信息

关键词： Berchemia floribunda Anthraquinone Floribundiquinone E 2-Acetylphyscion

Design,synthesis and antiproliferative activity of novel 2,7-disubstituted triazolo[1,5-a]pyrimidines

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Chinese Chemical Letters 2009年第10期20卷 1179-1182页

作者： xin Zhai Nan Jiang Ke Liang zhang Feng Bao Ping Gong Key Lab of New Drugs Design and Discovery of Liaoning Province School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 China Liaoning Food and Drug Administration Technical Evaluation Center Shenyang 110003 China

In our efforts to identify novel potent anticancer agents, we synthesized a series of 2,7-disubstituted triazolo[1,5-a]pyrimidines （6-16）. Their antiproliferative activity against Bel-7402, HT- 1080 and WI-38 cell lines was tested by MTT assay in vitro. Four of the compounds （9-11 and 16） displayed promising antiproliferative activity superior to gefitinib, especially compound 9. A preliminary SAR study of these derivatives was performed.

关键词： Triazolo[1,5-a]pyrimidines Synthesis Antiproliferative activity

Non-Chinese Immigrants： Challenge Faced by Yunnan of China to Achieve the 90–90–90 Goals

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Virologica Sinica 2018年第3期33卷 291-293页

作者： xin Chen Lin Duo Mei Ye Chiyu zhang Yong-Tang Zheng Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Pathogen Discovery and Big Data Center CAS Key Laboratory of Molecular Virology and Immunology Institut Pasteur of Shanghai Chinese Academy of SciencesShanghai 200031 China Yunnan Fuwai Cardiovascular Hospital Kunming 650032China

China’s AIDS epidemic started among people who inject drugs(PWID)in Ruili county-level city,a China–Myanmar border city of Yunnan Province,in 1989(Fig.1).Since then HIV has spread rapidly across the country(He and D... 详细信息

关键词：中国云南移民流行病爱滋病注射药 HIV 城市

The distribution and composition of hydrocarbons in sediments of the South Mid-Atlantic Ridge

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Acta Oceanologica Sinica 2018年第1期37卷 89-96页

作者： HUANG xin CHEN Shuai WANG Xiaoyuan zhang Shuwen CHEN Fajin PU Xiaoqiang Guangdong Province Key Laboratory of Coastal Ocean Variation and Disaster Prediction Guangdong Ocean University Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology

Sediment samples obtained from the South Mid-Atlantic Ridge are analyzed by a gas chromatography-mass spectrometer（GC-MS） for the abundances and distributions of hydrocarbons. The hydrocarbons in the samples exhibit a bimodal distribution of n-alkanes and are rich in 3-methylalkanes, 8-methylalkanes and 2, 4,（n-1）-trimethylalkanes, which may be the result of metabolic activity of benthic microorganism. Terpanes, hopanes and steranes are all enriched in the samples, which also support the microbial origin of hydrocarbons in *** and hydrocarbons in the samples show a trend that the contents are the highest in the Samples 22V-TVG10 and 26V-TVG05 collected near hydrothermal areas, and the lowest in samples 22IV-TVG01, 22V-TVG11,and 22V-TVG14 collected far from the hydrothermal areas, which suggest the possible influence on the samples by hydrothermal activity.

关键词： hydrocarbons South Mid-Atlantic Ridge sediment hydrothermal activity

Numerical simulation of diesel combustion based on n-heptane and toluene

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Propulsion and Power Research 2019年第2期8卷 121-127页

作者： Kesong zhang Qiangzhi xin Zhenqian Mu Zhijian Niu Zhiming Wang School of Energy and Power Engineering Shandong UniversityJinan CityShandongChina Zibo Diesel Engine Company Zibo CityShandongChina

Considering the self-ignition characteristic and C/H ratio,n-heptane and toluene(6:4 by mass)are chosen to constitute diesel surrogate fuel,and a reduced oxidation mechanism was *** mechanism was firstly validated by the combustion of diesel fuel in different oxygen concentrations within a constant volume vessel by high-speed *** simulated flame temperature distribution reproduces the diesel combustion process quite *** further validation,combustion in real diesel engine was also investigated numerically and experimentally using a light duty diesel and a marine *** calculated pressure curves in different operation conditions fit the measured data reasonably *** oxidation mechanism could reproduce the main characteristics including combustion phase and NOx emission of diesel combustion in different cases.

关键词： Diesel combustion Reduced mechanism n-heptane Toluene

Scalable preparation of porous silicon nanoparticles and their application for lithium-ion battery anodes

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Nano Research 2013年第3期6卷 174-181页

作者： Mingyuan Ge Jiepeng Rong xin Fang Anyi zhang Yunhao Lu Chongwu Zhou Department of Chemical Engineering and Materials Science University of Southern California 3710 McClintockAve Los Angeles CA 90089 USA Department of Materials Science and Engineering Zhejiang University 38 Zheda Road Hangzhou 310027 China Department of Electrical Engineering University of Southern California 3710 McClintock Ave Los Angeles CA 90089 USA

Nanostructured silicon has generated significant excitement for use as the anode material for lithium-ion batteries; however, more effort is needed to produce nanostructured silicon in a scalable fashion and with good performance. Here, we present a direct preparation of porous silicon nanoparticles as a new kind of nanostructured silicon using a novel two-step approach combining controlled boron doping and facile electroless etching. The porous silicon nanoparticles have been successfully used as high performance lithium-ion battery anodes, with capacities around 1,400 mA.h/g achieved at a current rate of 1 A/g, and 1,000 mA.h/g achieved at 2 A/g, and stable operation when combined with reduced graphene oxide and tested over up to 200 cycles. We attribute the overall good performance to the combination of porous silicon that can accommodate large volume change during cycling and provide large surface area accessible to electrolyte, and reduced graphene oxide that can serve as an elastic and electrically conductive matrix for the porous silicon nanoparticles.

关键词： porous siliconnanoparticles scalable production lithium-ion battery

Prevention and Treatment of Pneumoconiosis in the Context of Healthy China 2030

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China CDC weekly 2023年第41期5卷 927-932页

作者： Huanqiang Wang Qiao Ye Huadong zhang xin Sun Tao Li National Institute of Occupational Health and Poison Control Chinese Center for Disease Control and PreventionBeijingChina Department of Occupational Medicine and Toxicology Clinical Center for Interstitial Lung DiseasesBeijing Institute of Respiratory MedicineBeijing Chao-Yang Hospital Capital Medical UniversityBeijingChina Chongqing Center for Disease Control and Prevention ChongqingChina

Since the onset of reform and opening-up policies,China has risen to become the world’s second-largest *** transformative period has witnessed considerable advancements in medical services provision,resulting in significant improvements in the overall healthcare landscape.A noteworthy accomplishment is the creation of the world’s largest and most comprehensive social security *** to principles of inclusivity,multi-tiered coverage,and long-term sustainability,this system guarantees the fulfillment of basic life necessities.

关键词： services accomplishment advancement

Global Exponential Stability of a Class of Neural Networks with Delays

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 43-50页

作者： Feng-jian Yang Chao-long zhang Chuan-yong Chen xin-ming Chen Department of Computational Science Zhongkai University of Agriculture and Engineering Guangzhou 510225China

This paper is concerned with the stability of neural networks with time-varying delays. Under assumption that the nonlinear stimulate functions are Lipschitz continuous, by means of generalized Halanay inequalities, Dini＇s derivative and functional analysis techniques, several globally exponential stability criteria are established, which are only dependent on the parameters of the system.

关键词： Neural network Halanay's inequality delay globally exponential stability

Accuracy and Consistency of the Explicit-Invariant Energy Quadratization Approach for the Cahn-Hilliard Equation

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Journal of Mathematical Research with Applications 2025年第1期 84-104页

作者： Jun zhang Fangying SONG Yu zhang Computational Mathematics Research Center Guizhou University of Finance and Economics School of mathematics and statistics Guizhou University of Finance and Economics School of Mathematics and Stastistics Fuzhou University

It is well known that the explicit-invariant energy quadratization (EIEQ) approach can generate fully decoupled, linear and unconditionally energy-stable numerical schemes, so it is favored by many researchers. However, the undeniable fact is that the numerical method obtained by EIEQ approach preserves the “modified” energy law instead of the original *** is mainly due to the introduction of some auxiliary variables in EIEQ scheme, and the truncation error will make the auxiliary variables deviate from the original definition in the process of numerical calculation. The primary objective of this paper is to address this gap by providing the accuracy and consistency of the EIEQ method in the context of the CahnHilliard equation. We introduce a relaxation technique for auxiliary variables and construct two numerical schemes based on EIEQ. The analysis results show that the newly constructed schemes are not only unconditionally energy stable, linear and fully decoupled, but also can effectively correct the errors introduced by auxiliary variables and follow the original energy ***, several 2D and 3D numerical examples illustrate the accuracy and efficiency of the newly constructed numerical schemes.

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