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食品科技 2002年第7期27卷 60-63页

作者：彭喜春段杉彭志英华南理工大学食品学院广州510640

介绍了可食膜的发展概况、在水果中应用可食膜进行短期保鲜所存在的问题,并从保鲜膜本身的气体渗透性、果蔬组织的扩散性、果内气体组成成分等三个方面的计算和测量着手,阐述了得到可食膜保鲜最佳效果的方法。

关键词：水果可食保鲜膜应用选择

Comparative study on epidemiological and etiological characteristics of patients with acute diarrhea with febrile or non-febrile symptoms in China

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Infectious Diseases of Poverty 2023年第4期12卷 17-28页

作者： Tao Wang Gang Wang chun-xi shan Yan-Qun Sun xiang Ren Lin-Jie Yu Yi-Fei Wang Sheng-Hong Lin xiao-Ai Zhang Hao Li Cui-Hong Zhang Meng-Jie Geng Wei-Zhong Yang Li-Ping Wang Wei Liu Li-Qun Fang Department of Epidemiology and Biostatistics School of Public HealthWuhan UniversityWuhanHubeiPeople’s Republic of China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology20 Dong-Da StreetFengtai DistrictBeijing100071People’s Republic of China Nanjing Center for Disease Control and Prevention NanjingPeople’s Republic of China Division of Infectious Disease Key Laboratory of Surveillance and Early-Warning On Infectious DiseaseChinese Center for Disease Control and PreventionNo.155 Changbai RoadChangping DistrictBeijing102206People’s Republic of China Chinese Center for Disease Control and Prevention BeijingPeople’s Republic of China

Background Acute diarrhea with fever can potentially represent a more severe form of the disease compared to non-febrile diarrhea. This study was to investigate the epidemiological characteristics and enteric pathogen composition of febrile-diarrheal patients, and to explore factors including pathogens associated with fever by age *** A nationwide surveillance study of acute diarrheal patients of all ages was conducted in 217 sentinel hospitals from 31 provinces (autonomous regions or municipalities) in China between 2011 and 2020. Seventeen diarrhea-related pathogens, including seven viruses and ten bacteria, were investigated and their association with occurrence of fever symptoms was assessed using multivariate logistic *** A total of 146,296 patients with acute diarrhea (18.6% with fever) were tested. Th diarrheal children below 5 years had the highest frequency of fever (24.2%), and related to significantly higher prevalence of viral enteropathogens (40.2%) as compared with other age groups (P < 0.001). Within each age group, the febrile-diarrheal patients were associated with a significantly higher prevalence of bacterial pathogens than afebrile-diarrheal patients (allP < 0.01). There was discrepancy when each pathogen was compared, i.e., nontyphoidalSalmonella (NTS) was over-represented in febrile vs non-febrile patients of all age groups, while the febrile vs non-febrile difference for diarrheagenicEscherichia coli (DEC) was only significant for adult groups. The multivariate analysis revealed significant association between fever and infection with rotavirus A among children [odds ratio (OR) = 1.60], for DEC in adult groups (OR = 1.64), for NTS in both children (OR = 2.95) and adults (OR = 3.59).Conclusions There are significant discrepancy of the infected enteric pathogens in patients with acute diarrhea with fever between age groups, and it is valuable for priority detection of NTS and rotavirus A in patients with children < 5 years

关键词： Acute diarrhea Epidemiology Enteropathogens Fever China

GC-MS法同时测定扎冲十三味丸中麝香酮和丁香酚含量

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中国民族医药杂志 2017年第1期23卷 46-48页

作者：韩春平席海山李江内蒙古民族大学化学化工学院内蒙古通辽028042 内蒙古民族大学分析测试中心内蒙古通辽028042

目的:建立GC-MS法同时测定蒙药扎冲-13中麝香酮和丁香酚的含量。方法:色谱柱为HP-5MS(30m×0.25mm×0.25μm);程序升温,初始温度50℃,以10℃min^(-1)升温至120℃,再以20℃·min^(-1)升温至250℃;汽化室温度为260℃;高纯度He气为载气;载... 详细信息

目的:建立GC-MS法同时测定蒙药扎冲-13中麝香酮和丁香酚的含量。方法:色谱柱为HP-5MS(30m×0.25mm×0.25μm);程序升温,初始温度50℃,以10℃min^(-1)升温至120℃,再以20℃·min^(-1)升温至250℃;汽化室温度为260℃;高纯度He气为载气;载气流速为2m L·min^(-1);进样量为1μL;分流比为20:1。结果:麝香酮标准曲线为Y=693570.6+1.43739×10~8×X(R=0.9993,N=5);丁香酚标准曲线为Y=1.65309×10~8+5.03683×10~8×X(R=0.9957,N=5);样品中丁香酚的平均含量为0.2325%、麝香酮的平均含量为0.0110%;RSD分别为1.2026%和0.6350%。结论:该方法简便、快速、准确,适用于蒙药中丁香酚、麝香酮的含量测定。

关键词： GC-MS法扎冲-13 丁香酚麝香酮含量

Prevalence of Helicobacter pylori infection in Chinese military personnel:A cross-sectional,multicenter-based study

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World Journal of Gastroenterology 2025年第3期31卷 42-49页

作者： Han-Chen Min chun-Yan Zhang Fang-Yu Wang xiao-Hui Yu shan-Hong Tang Hong-Wu Zhu Ya-Gang Zhao Ji-Luo Liu Jian Wang Jing-Han Guo xiao-Mei Zhang Yun-Sheng Yang Chinese People’s Liberation Army Medical School Chinese People’s Liberation Army General HospitalBeijing 100853China Department of Gastroenterology and Hepatology The First Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China Sixth Healthcare Department The Second Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China Department of Gastroenterology The 940th Hospital of Joint Logistic Support Force of Chinese People’s Liberation ArmyLanzhou 730050Gansu ProvinceChina Department of Gastroenterology General Hospital of Western Theater CommandChengdu 610011Sichuan ProvinceChina Department of Gastroenterology General Hospital of Southern Theater CommandGuangzhou 510010Guangdong ProvinceChina Department of Epidemiology Naval Medical UniversityShanghai 200433China School of Medicine Nankai UniversityTianjin 300071China National Clinical Research Center for Geriatric Diseases Chinese People’s Liberation Army General HospitalBeijing 100853China

BACKGROUND Helicobacter pylori(***)infection is a prevalent disease encountered in military internal medicine and recognized as the main cause of dyspepsia,gastritis,and peptic ulcer,which are common diseases in military *** guidelines in China state all patients with evidence of active infection with *** are offered ***,the prevalence of *** infection and its regional distribution in the military population remain unclear,which hinders effective prevention and treatment *** the prevalence of *** infection in the military population will aid in the development of customized strategies to better manage this infectious *** To investigate the prevalence of *** infection in the Chinese military population in different geographic *** This multicenter,retrospective study included 22421 individuals from five tertiary hospitals located in north,east,southwest,and northwest cities of *** infection was identified using the urea breath test,which had been performed between January 2020 and December *** Of the 22421 military service members,7416(33.1%)were urea breath *** highest prevalence of *** was in the 30-39 years age group for military personnel,with an infection rate of 34.9%.The majority of infected subjects were younger than 40-years-old,accounting for 70.4%of the infected *** individuals serviced in Lanzhou and Chengdu showed a higher infection prevalence than those in Beijing,Nanjing,and Guangzhou,with prevalence rates of 44.3%,37.9%,29.0%,31.1%,and 32.3%,*** *** infection remains a common infectious disease among military personnel in China and has a relatively high prevalence rate in northwest China.

关键词： Helicobacter pylori Prevalence Military personnel Urea breath test Multicenter study

Spheroidizing Behavior and Spheroidizing Kinetics of W-phase During Solid-Solution Treatment in Mg–Zn–Y–Mn–(B)Alloys

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 464-469页

作者： Kai Yang Jin-shan Zhang xi-Mei Zong Wei Liu chun-xiang Xu College of Materials Science and Engineering TaiyuanUniversity of Technology Taiyuan 030024 China shanxi Key Laboratory of Advanced Magnesium-based Materials Taiyuan 030024China

The spheroidizing mechanism of W-phase in the Mg–Zn–Y–Mn–（B） alloys during solid-solution treatment was investigated by using kinetic methodologies. The microstructure and mechanical properties of heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy containing 0.003 wt% B were compared with heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy. The heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy with 0.003 wt% B contained fine and uniform W-phase particles, which exhibited optimal mechanical performance. The ultimate tensile strength, yield strength and elongation were 287.7, 125.5 MPa and 21.1%,respectively.

关键词： Magnesium alloys W-phase Spheroidizing Kinetics Microstructure Mechanical properties

Effect of Precipitated Phases on Corrosion of Mg95.8Gd3Zn1Zr0.2 Alloy with Long-Period Stacking Ordered Structure

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 32-38页

作者： xi-Mei zong Dan Wang Wei Liu Kai-Bo Nie chun-xiang Xu Jin-shan Zhang College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China shanxi Key Laboratory of Advanced Magnesium-Based Materials Taiyuan 030024 China Department of Chemistry Taiyuan Normal UniversityTaiyuan 030031 China

The microstructure of the precipitated phases of ***3Zn1Zro.2 alloys with long-period stacking ordered structure before and after heat treatment is discussed. The corrosion properties of the as-cast （F）, solid-solution （T4） and aging-treated （T6） alloys in 1% NaC1 solution are studied. The hydrogen evolution and electrochemical measurements display that the as-cast ***3Zn1Zro.2 alloy with the continuous network eutectic phase exhibits the greatest corrosion resistance, while T6 sample with some needle-like phases and the particle phases is the worst among the three alloys. It is proposed to be mainly related to the amount, composition, microstructure and distribution of the precipitated phases.

关键词： Mg-Gd-Zn Corrosion properties Long-period stacking ordered (LPSO) Microstructure

Plasmonic photo-assisted electrochemical sensor for detection of trace lead ions based on Au anchored on two-dimensional g-C_(3)N_(4)/graphene nanosheets

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Rare Metals 2021年第7期40卷 1727-1737页

作者： Jia-Yue Hu Zhi Li chun-Yang Zhai Jun-Feng Wang Li-xi Zeng Ming-shan Zhu School of Environment Jinan UniversityGuangzhou 510632China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Department of Chemistry University of TorontoToronto M5S 3H6Canada

In this paper,a plasmonic photo-assisted electrochemical sensor,Au anchored on two-dimensional(2 D)graphitic carbon nitride(g-C_(3)N_(4))/reduced graphene oxide(rGO)nanosheets(Au/g-C_(3)N_(4)/rGO),was facile *** morphology and structure of the composite are characterized by transmission electron microscope,X-ray photoelectron spectroscopy,X-ray diffraction and ultraviolet-visible spectrophotometer(UV-Vis).Based on the semiconductor of g-C_(3)N_(4) and optical properties of surface plasmon resonance for Au,the as-prepared Au/g-C_(3)N_(4)/rGO showed high sensitivity for the detection of trace lead ion[Pb(Ⅱ)]by differential pulse anodic stripping voltammetry in the presence of visible light *** optimized conditions,the limit of detection(signal-to-noise ratio(S/N)=3)Pb(Ⅱ)detection can be low to0.1 nmol·L^(-1).In addition,the interference research and real soil sample detection were measured to confirm the possibility of practical applications.

关键词： Pb(Ⅱ) Electrochemical detection Au g-C_(3)N_(4) Surface plasmon resonance Visible light

An Intrinsic Model for the Polarization Position Angle Swing Observed in QSO 1150+812

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Chinese Journal of Astronomy and Astrophysics 2004年第1期4卷 37-50页

作者： shan-JieQian xi-ZhenZhang NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012

The rapid polarization position angle swing of ~ 180° observed in QSO 1150+812 at 2cm by Kochenov and Gabuzda is quite a regular event. One interesting property of the event is that, during the time of the swing the polarized flux density remained almost constant. We suggest that such an event can be explained in terms of a relativistic thin shock propagating through a uniform helical magnetic field, giving rise to relativistic aberration effects as the transverse field component rotates. The model may also be applicable to other similar events in which variations in polarization are not accompanied by variations in total flux density.

关键词： radio continuum: galaxies polarization quasars: individual: QSO 1150+812

The Maximum Surplus before Ruin and Related Problems in a Jump-Diffusion Renewal Risk Process

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2379-2394页

作者： shan shan WANG chun Sheng ZHANG Department of Mathematics Tianjin Polytechnic University Tianjin 300160 P. R. China School of Mathematics and LPMC Nankai University Tianjin 300071 P. R. China

In this paper, we investigate a Sparre Andersen risk model perturbed by diffusion with phase-type inter-claim times. We mainly study the distribution of maximum surplus prior to ruin. A matrix form of integro-differential equation for this quantity is derived, and its solution can be expressed as a linear combination of particular solutions of the corresponding homogeneous integro-differential equations. By using the divided differences technique and nonnegative real part roots of Lundberg＇s equation, the explicit Laplace transforms of particular solutions are obtained. Specially, we can deduce closed-form results as long as the individual claim size is rationally distributed. We also give a concise matrix expression for the expected discounted dividend payments under a barrier dividend strategy. Finally, we give some examples to present our main results.

关键词： Sparre Andersen risk model phase-type inter-claim times maximum surplus before ruin,expected present value of dividends barrier dividend strategy diffusion integro-differential equation

Theoretical Study of Haloacetonitrile Anions： CH2XCN^- （X=F, Cl）

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Chinese Journal of Chemical Physics 2008年第3期21卷 255-262页

作者： xin-wen Zhang Mei Li shan-xi Tian Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technologyof China Hefei 230025 China Department of Chemical Physics University of Science and Technology of China Hefei 230026China

Haloacetonitrile anions CH2XCN- （X=F, Cl） were studied by HF-SCF, Becke3-LYP, and MP2 methods together with the Dunning＇s basis set aug-cc-PVTZ. The vertical electron attachments to the neutral are endothermic. The geometrically optimized CH2FCN^- is mainly a valence-bounded anion and CH2FCN→CH2CN＋F^- is a nonadiabatic dissociation. This theoretical study in good agreement with the experimental results shows that the Becke3-LYP method is reasonable in describing the electronic structures of anions and dissociative attachment dynamics, while significant differences between MP2 and Becke3-LYP results are shown for the dissociation potential curves of CH2ClCN→CH2CN＋Cl^-.

关键词： Haloacetonitrile Electron attachment Dissociation dynamics Electron correlation effect