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Chinese Chemical Letters 2010年第10期21卷 1191-1194页

作者： xin ying zhang ying ying Qu Xue Sen Fan School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

An environmentally benign and highly efficient one-pot preparation of α-aminophosphonates under solvent-free conditions was developed. By employing this method, 5-aminophosphonate substituted pyrimidine nucleosides were synthesized in good to excellent yields starting from 5-forrnyl-2＇-deoxyuridine, aniline and dimethylphosphite.

关键词： Aminophosphonate 5-Substituted pyrimidine nucleoside Solvent-free reaction Green synthesis

Indoor channel characteristics based on wideband MIMO measurements at 5.25 GHz

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 46-50页

作者： GAO xin-ying zhang Jian-hua zhang Ping Key Laboratory of Universal Wireless Communications Ministry of Education Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

Extensive indoor channel measurements were conducted in Beijing with wideband multiple-input multiple-output （MIMO） sounder at 5.25 GHz. Both line-of-sight （LOS） and non-line-of-sight （NLOS） propagation were measured in the indoor office and hotspot scenarios. On the basis of measured data, statistical channel characteristics are presented in this article, including the empirical path loss （PL） models, three excess delay parameters, circular azimuth spread （CAS）, and circular elevation spread （CES）. Comparative analysis of different propagation mechanisms in two scenarios is conducted. These values are significant for indoor coverage and technical research of MIMO and orthogonal frequency division multiplexing （OFDM） for the international mobile telecommunications-advanced （IMT-Advanced） system.

关键词： channel measurement wideband MIMO path loss excess delay circular azimuth spread circular elevation spread IMT-Advanced

Synthesis of 1,2-allenic ketones through oxidation of homopropargyl alcohols with CrO_3(cat.)/TBHP under MWI

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Chinese Chemical Letters 2011年第3期22卷 268-271页

作者： xin ying zhang ying ying Qu Yang Yang Wang Xue Sen Fan School of Chemistry and Environmental Science Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

A CrO3 catalyzed oxidation of homopropargyl alcohols with tert-butyl hydroperoxide under microwave irradiation was found to be an efficient and rapid alternative for the preparation of 1,2-allenic *** advantages of th... 详细信息

关键词： Allenic ketones Oxidation Microwave irradiation Chromium(Ⅵ) oxide tert-Butyl hydroperoxide

Multidrug-resistant organisms in intensive care units and logistic analysis of risk factors

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World Journal of Clinical Cases 2022年第6期10卷 1795-1805页

作者： ying Han Jin zhang Hong-Ze zhang xin-ying zhang Ya-Mei Wang Infection Control Office Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina

BACKGROUND Intensive care unit(ICU)patients are critically ill and have low *** will undergo various trauma medical procedures during diagnosis and *** use of high-dose hormones and broad-spectrum antibiotics will increase the incidence of nosocomial infection in ICU ***,it is necessary to explore the causes of nosocomial infection in ICU and provide basis for the prevention and control of nosocomial infection in *** To explore major pathogens of nosocomial infection in ICUs,methods of detection and drug resistance *** Risk factors of multidrug-resistant infection were analyzed to provide a basis for clinical rational use of antimicrobial drugs in the *** findings were used to standardize rational use of antimicrobial *** PhoenixTM100 automatic bacterial identification analyzer was used to for cell identification in specimens collected from the ICU between January 2016 and December *** sensitivity tests were carried out and drug resistance trends were analyzed using the optical disc diffusion *** ratios and corresponding 95%CI of independent variables were calculated using a logistic regression *** elimination(trend=0.1)was used as an inclusion criterion for multivariate *** data were analyzed using SPSS version 22.0,and P<0.05 was considered statistically *** We collected 2070 samples from ICU patients between January 2016 and December *** types comprised sputum(1139 strains,55.02%),blood(521 strains,25.17%),and drainage fluid(117 strains,5.65%).A total of 1051 strains of major pathogens,including Acinetobacter baumannii,Escherichia coli(***),Pseudomonas aeruginosa(***),Klebsiella pneumoniae(***)and Staphylococcus aureus,were detected,with a detection rate of 35.97%(378/1051).Most of these strains were resistant to *** rate of *** was 21.79%(229/1051),and it was generally sensitive to many antimicrobial dr

关键词： Multidrug-resistant organisms Intensive care Antibiotics Drug resistance

Preparation of nucleoside-pyridine hybrids and pyridine attached acylureas from an unexpected uracil ring-opening and pyridine ring-forming sequence

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Chinese Chemical Letters 2009年第10期20卷 1161-1165页

作者： Xue Sen Fan Xia Wang xin ying zhang Dong Feng ying ying Qu School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

Novel pyrimidine nucleoside-3,5-dicyanopyridine hybrids （4） or pyridine attached acylureas （5） were selectively and efficiently prepared from the reaction of 2′-deoxyuddin-5-yl-methylene malononitrile （1）, malononitrile （2） and thiophenol （3） or from an unexpected uracil ring-opening and pyddine ring-forming sequence via the reaction of 1 and 3. It is the first time such a sequence has ever been reported.

关键词： Pyrimidine nucleoside Pyridine Acylureas Ring-opening and -forming reaction

Synthesis of fused pyran and arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane in ionic liquid

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Chinese Chemical Letters 2009年第4期20卷 387-390页

作者： Xue Sen Fan ying ying Qu xin ying zhang Xia Wang Jian Ji Wang School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis（4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl）methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis（pyranon-3-yl）methane hybrids with potential biological activities were constructed.

关键词： Ionic liquid Fused pyran Arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane Pyrimidine nucleoside Green synthesis

Development of a low-loss magnetic-coupling pickup for 166.6-MHz quarter-wave beta=1 superconducting cavities

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Nuclear Science and Techniques 2020年第9期31卷 25-32页

作者： Tong-Ming Huang Pei zhang Zhong-Quan Li xin-ying zhang Hai-ying Lin Qiang Ma Fan-Bo Meng Wei-Min Pan Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Acceleration Physics and Technology IHEPCASBeijing 100049China School of Nuclear Sciences and Technology University of Chinese Academy of SciencesBeijing 100049China

166.6-MHz quarter-waveβ=1 superconducting cavities have been adopted for the High Energy Photon Source,a 6-GeV diffraction-limited synchrotron light source currently under construction.A large helium jacket was required to accommodate the enlarged cavity beam pipe for the heavy damping of higher-order modes;the original electric-probe pickup thus becomes inevitably long with unfavorable mechanical *** to an existing high-pressure-rinsing port,a magnetic-loop pickup was designed,characterized by low radio-frequency and cryogenic losses and being multipacting-free and insensitive to manufacturing and assembly *** consequent removal of the original pickup port from the cavity largely simplified the helium jacket fabrication and may also reduce cavity *** paper presents a comprehensive design of a low-loss magnetic-coupling pickup for quarter-waveβ=1 superconducting *** design can also be applied to other non-elliptical structures.

关键词： Pickup Magnetic coupling Quarter-wave cavity Superconducting cavity Low loss Synchrotron light source

Biochemical, molecular, and morphological variations of flight muscles before and after dispersal flight in a eusocial termite, Reticulitermes chinensis

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Insect Science 2021年第1期28卷 77-92页

作者： Zhen-Yu zhang Jing Ren Fei Chu Jun-Xia Guan Guang-Yu Yang Yu-Tong Liu xin-ying zhang Si-Qin Ge Qiu-ying Huang Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina

Swarming behavior facilitates pair formation,and therefore mating,in many eusocial ***,the physiological adjustments and morphological transformations of the flight muscles involved in flying and flightless insect forms are still ***,we found that the dispersal flight of the eusocial termite Reticulitermes chinensis Snyder led to a gradual decrease in adenosine triphosphate supply from oxidative phospho・rylation,as well as a reduction in the activities of critical mitochondrial respiratory enzymes from preflight to ***,using three-dimensional reconstruction and transmission electron microscopy(TEM),the flight muscles were found to be gradually deteriorated during this *** particular,two tergo-pleural muscles(IItpm5 and IIItpm5)necessary to adjust the rotation of wings for wing shedding behavior were present only in flying *** findings suggest that flight muscle systems vary in function and morphology to facilitate the swarming flight procedure,which sheds light on the important role of swarming in successful extension and fecundity of eusocial termites.

关键词： dispersal flight eusocial termite flight muscle mitochondrial oxidative phosphorylation swarming behavior three-dimensional reconstruction

Synthesis of cyclopentenyl and cyclohexenyl ketones via [3 + 2] and [4 + 2] annulations of 1,2-allenic ketones

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Chinese Chemical Letters 2014年第1期25卷 55-57页

作者： Liang-Yan Cui Sheng-Hai Guo Bin Li xin-ying zhang Xue-Sen Fan School of Chemistry and Chemical Engineering Key Laboratory of Green Chemical Media and ReactionsMinistry of EducationHenan Key Laboratory for Environmental Pollution ControlHenan Normal University

In this paper, an efficient synthesis of cyclopentenyl ketones and cyclohexenyl ketones through tertiary phosphine catalyzed [3 ＋ 2] and [4 ＋ 2] annulations of 1,2-allenic ketones with activated alkenes has been developed. Compared with published synthetic methods on cyclopentenyl ketones and cyclohexenyl ketones, the protocols developed in this paper have the advantages such as readily available starting materials, mild reaction conditions and high efficiency.

关键词： Cyclopentenylketone Cyclohexenyl ketone 1 2-Allenic ketone Phosphine-catalyzed annulation

Copper-catalyzed tandem reaction of 2-bromobenzyl bromides with 1,3-dicarbonyl compounds leading to 4H-chromenes

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Chinese Chemical Letters 2012年第10期23卷 1129-1132页

作者： xin ying zhang Liang Liang Fang Nan Liu Hua Yue Wu Xue Sen Fan School of Chemistry and Environmental Science Key Laboratory for Yellow River and Huai River Water Environment and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiang 453007China College of Chemistry&Materials Engineering Wenzhou UniversityWenzhou 325027China

A Cu（I）-catalyzed one-pot tandem reaction of 2-bromobenzyl bromides with 1,3-dicarbonyl compounds leading to 4H- chromene derivatives has been developed. This new approach toward 4H-chromenes combines several reacti... 详细信息

关键词： One-pot tandem reaction 4H-Chromenes Copper catalysis