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Efficient fluorescence detection of a single neutral atom with low background in a microscopic optical dipole trap

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Science China(Physics,Mechanics & Astronomy) 2012年第9期55卷 1523-1528页

作者： GUO YanQiang LI Gang zhang YanFeng zhang PengFei WANG junmin zhang TianCai State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Shanxi University Taiyuan 030006 China

A single cesium atom is trapped in a far-off-resonance optical dipole trap （FORT） from the magneto-optical trap （MOT） and directly imaged by using a charge-coupled device （CCD） camera. The binary single-atom steps and photon anti-bunching are observed by a photon-counting-based HBT system using fluorescence light. The average atom dwelling time in the FORT is about 9 s. To reduce the background noise in the detection procedure we employ a weak probe laser tuned to the D1 line to il- lurninate the single atom from the direction perpendicular to the large-numerical-aperture collimation system. The second or- der degree of coherence g（2）（r）=0.12_＋0.02 is obtained directly from the fluorescence light of the single atom without deducting the background. The background light has been suppressed to 10 counts per 50 ms, which is much lower compared with the reported results. The measured g（2）（r） is in good agreement with theoretical analysis. The system provides a simple and effi- cient method to manipulate and measure single neutral atoms, and opens a way to create an efficient controlled single-photon source.

关键词： magneto-optical trap (MOT) far-off-resonance optical dipole trap (FORT) single atom collisional blockade second- order correlation function

Dietary Epimedium extract supplementation improves intestinal functions and alters gut microbiota in broilers

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1584-1597页

作者： Jiaqi zhang Haitao Yu Huiyan zhang Qingyu Zhao Wei Si Yuchang Qin junmin zhang State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agricultural Sciences100193 BeijingChina Scientific Observing and Experiment Station of Animal Genetic Resources and Nutrition in North China of Ministry of Agriculture and Rural Affairs Institute of Animal Sciences of Chinese Academy of Agricultural Sciences100193 BeijingChina.

Background Growth-promoting antibiotics have been banned by law in the livestock and poultry breeding industry in many *** alternatives to antibiotics have been investigated for using in ***(EM)is an herb rich in flavonoids that has many beneficial effects on ***,this study was planned to explore the potential of EM as a new alternative antibiotic product in animal *** A total of 7201-day-old male broilers(Arbor Acres Plus)were randomly divided into six groups and fed basal diet(normal control;NC),basal diet supplemented with antibiotic(75 mg/kg chlortetracycline;CTC),and basal diet supplemented with 100,200,400 or 800 mg/kg EM extract for 6 weeks(EM100,EM200,EM400 and EM800 groups).The growth performance at weeks 3 and 6 was ***,intestinal tissue and feces were collected to assay for antioxidant indexes,intestinal permeability,lactic acid and short-chain fatty acids(SCFAs)profiles,microbial composition,and expression of intestinal barrier *** The average daily feed intake in CTC group at 1-21 d was significantly higher than that in the NC group,and had no statistical difference with EM *** with NC group,average daily gain in CTC and EM200 groups increased significantly at 1-21 and 1-42 *** with NC group,EM200 and EM400 groups had significantly decreased levels of lipopolysaccharide and D-lactic acid in serum throughout the *** concentrations of lactic acid,acetic acid,propionic acid,butyric acid and SCFAs in feces of birds fed 200 mg/kg EM diet were significantly higher than those fed *** dietary supplementation of chlortetracycline and 200 mg/kg EM significantly increased ileal expression of SOD1,Claudin-1 and ZO-1 *** supplemented with 200 mg/kg EM increased the relative abundances of g_NK4A214_group and Lactobacillus in the jejunal,while the relative abundances of Microbacterium,Kitasatospora,Bacteroides in the jejunal and Gallibacterium

关键词： Antioxidation Broilers Epimedium Growth performance Microbiota

Harmonic analysis based on time domain mutual-multiplication window

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Journal of Modern Power Systems and Clean Energy 2016年第1期4卷 47-53页

作者： Tianyuan TAN Wenjuan CHEN Kaipei LIU Niu XIONG junmin zhang Junhua WANG School of Electrical Engineering Wuhan UniversityWuhan 430072China School of Computer Science South-Central University for NationalitiesWuhan 430072China

The signal spectral leakage and fence effect are prone to take place during the power harmonic analysis by fast fourier transform(FFT) under asynchronous *** inhibiting ability of classical window functions is restricted by side-lobe behaviors. A new type window function called time domain mutual-multiplication window, is obtained by multiplication operation of several window functions. A novel approach of harmonic analysis is developed through analyzing performances of main-lobe and side-lobe of the new window. Simulation results show that the time domain mutual-multiplication window can significantly suppress frequency spectral leakage and improve the accuracy of harmonic parameter estimation.

关键词： Mutual-multiplication window Fast Fourier Transform Harmonic Analysis Main-lobe Side-lobe

Residual stress variation in SiC_(f)/SiC composite during heat treatment and its effects on mechanical behavior

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Journal of Advanced Ceramics 2020年第5期9卷 567-575页

作者： Xiaowu CHEN Guofeng CHENG junmin zhang Feiyu GUO Haijun ZHOU Chunjin LIAO Hongda WANG Xiangyu zhang Shaoming DONG State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Analysis and Testing Center for Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China School of Physical Science and Technology ShanghaiTech UniversityShanghai 200031China

Residual stress originated from thermal expansion mismatch determines the mechanical properties of ceramic matrix composites(CMCs).Here,continuous SiC fiber reinforced SiC matrix(SiC_(f)/SiC)composites were fabricated by nano-infiltration and transient eutectic-phase(NITE)method,and the residual stress of the composites was investigated using high-temperature Raman *** temperature increasing from room temperature to 1400℃,the residual stresses of the matrix and the fiber decrease from 1.29 to 0.62 GPa and from 0.84 to 0.55 GPa in compression respectively,while that of the interphase decreases from 0.16 to 0.10 GPa in *** variation of residual stress shows little effect on the tensile strength of the composites,while causes a slight decrease in the tensile *** suppression of fiber/matrix debonding and fiber pulling-out caused by the residual stress reduction in the interphase is responsible for the decreasing tensile *** work can open up new alternatives for residual stress analysis in CMCs.

关键词： residual stress nano-powder infiltration and transient eutectoid(NITE) Raman spectroscopy mechanical properties

Carotenoid enrichment in eggs:From biochemistry perspective

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Animal Nutrition 2023年第3期14卷 315-333页

作者： Dieudonne M.Dansou Huiyan zhang Yanan Yu Hao Wang Chaohua Tang Qingyu Zhao Yuchang Qin junmin zhang State Key Laboratory of Animal Nutrition and Feeding Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China

The emergence of safe and functional eggs for consumer acceptance has gained *** production of carotenoid-enriched eggs has received attention due to its multifunctional biological *** modification of laying hens’diet can be a strategy to produce such *** review presents the chemistry of carotenoids in nature and eggs,the accumulation process of carotenoids into eggs,and the functions of carotenoids in *** findings showed that carotenoids can be deposited into the egg and contribute to improving its nutritive *** biosynthesis,chemical structure,and metabolism pathways of carotenoids lead to the deposition of carotenoids into eggs in their original or metabolized ***,some factors modulate the efficiency of carotenoids in fowls before accumulation into ***-enriched eggs may be promising,ensuring the availability of highly nutritive ***,further studies are still needed to comprehend the full metabolism process and the extensive functions of carotenoids in eggs.

关键词： Egg enrichment Egg fortification Carotenoid chemistry Bioavailability Metabolism Function

Pt-Ru Catalysts Prepared by a Modified Polyol Process for Direct Methanol Fuel Cells

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贵金属 2012年第A1期33卷 222-226页

作者： zhang junmin ZHU Fangfang zhang Kunhua LIU Weiping GUAN Weiming State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Kunming Institute of Precious MetalsKunming 650106China

Supported PtRu/C catalysts used in direct methanol fuel cells (DMFCs) were prepared by a new modified polyol method. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and cyclic voltammograms (CVs) were carried out to characterize the morphology, composition and the electrochemical properties of the PtRu/C catalyst. The results revealed that the PtRu nanoparticles with small average particle size (≈2.5 nm), and highly dispersed on the carbon support. The PtRu/C catalyst exhibited high catalytic activity and anti poisoned performance than that of the JM PtRu/C. It is imply that the modified polyol method is efficient for PtRu/C catalyst preparation.

关键词： PtRu/C catalysts modified polyol method direct methanol fuel cells(DMFCs) electrochemical performance

Selenium deficiency induces spleen pathological changes in pigs by decreasing selenoprotein expression,evoking oxidative stress,and activating inflammation and apoptosis

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Journal of Animal Science and Biotechnology 2021年第4期12卷 1517-1529页

作者： Shuang Li Wenjuan Sun Kai zhang Jiawei Zhu Xueting Jia Xiaoqing Guo Qingyu Zhao Chaohua Tang Jingdong Yin junmin zhang State Key Laboratory of Animal Nutrition Institute of Animal Sciences of Chinese Academy of Agricultural SciencesBeijing 100193China State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Scientific Observing and Experiment Station of Animal Genetic Resources and Nutrition in North China of Ministry of Agriculture and Rural Affairs Institute of Animal Sciences of Chinese Academy of Agricultural SciencesBeijing 100193China

Background:The immune system is one aspect of health that is affected by dietary selenium(Se)levels and selenoprotein *** is an important immune organ of the body,which is directly involved in cellular ***,there are limited reports on Se levels and spleen ***,this study established a Se-deficient pig model to investigate the mechanism of Se deficiency-induced splenic ***:Twenty-four pure line castrated male Yorkshire pigs(45 days old,12.50±1.32 kg,12 full-sibling pairs)were divided into two equal groups and fed Se-deficient diet(0.007 mg Se/kg)or Se-adequate diet(0.3 mg Se/kg)for 16 *** the end of the trial,blood and spleen were collected to assay for erythroid parameters,the osmotic fragility of erythrocytes,the spleen index,histology,terminal deoxynucleotidyl transferase nick-end labeling(TUNEL)staining,Se concentrations,the selenogenome,redox status,and signaling related inflammation and ***:Dietary Se deficiency decreased the erythroid parameters and increased the number of osmotically fragile erythrocytes(P<0.05).The spleen index did not change,but hematoxylin and eosin and TUNEL staining indicated that the white pulp decreased,the red pulp increased,and splenocyte apoptosis occurred in the Se deficient *** deficiency decreased the Se concentration and selenoprotein expression in the spleen(P<0.05),blocked the glutathione and thioredoxin antioxidant systems,and led to redox *** deficiency activated the NF-κB and HIF-1αtranscription factors,thus increasing pro-inflammatory cytokines(IL-1β,IL-6,IL-8,IL-17,and TNF-α),decreasing anti-inflammatory cytokines(IL-10,IL-13,and TGF-β)and increasing expression of the downstream genes COX-2 and iNOS(P<0.05),which in turn induced *** addition,Se-deficiency induced apoptosis through the mitochondrial pathway,upregulated apoptotic genes(Caspase3,Caspase8,and Bak),and downregulated antiapoptotic genes(Bcl-2)(P<0.05)at the mRNA

关键词： Apoptosis Inflammation Oxidative stress Pigs Selenium deficiency Spleen

Exploringthe Cultivation of Intercultural Competence in Foreign Language Education

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学术界 2016年第8期 299-303页

作者： zhang junmin School of International Studies Henan Normal University

The pace of globalization leads to an unremitting attention on the cultivation of intercultural competence as well as intercultural citizenship *** article argues that cultural intelligence functions as an effective pathway to assess and develop one's ability of adaptation in a culturally diverse *** further analysis provides an evidence for the feasibility of integrating cultural intelligence development with foreign language education programs.

关键词：交际能力外语教学跨文化培养公民教育有限元分析文化背景智力发展

基于改进型自适应算法的谐波检测及其性能研究

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电力自动化设备 2011年第4期31卷 23-27页

作者：张俊敏中南民族大学计算机科学学院湖北武汉430074

通过对有源电力滤波器基本自适应谐波电流对消检测方法的研究,指出了基本自适应方法存在检测精度和动态响应之间的矛盾,证明了基本自适应系统是一个关于中心角频率对称的陷波器。理论推导证明了由于系统权向量不为一个恒定的值,导致该... 详细信息

通过对有源电力滤波器基本自适应谐波电流对消检测方法的研究,指出了基本自适应方法存在检测精度和动态响应之间的矛盾,证明了基本自适应系统是一个关于中心角频率对称的陷波器。理论推导证明了由于系统权向量不为一个恒定的值,导致该系统不能准确提取谐波电流。在此基础上提出了一种改进型模拟自适应对消检测方法,讨论了改进型自适应系统的稳定性。改进后系统是通过加入一个低通滤波器减小了陷波器参考角频率附近的带宽,系统实质上是一个关于中心角频率不对称的陷波器。该方法可在保证动态响应的前提下兼顾系统的检测精度。理论推导和仿真实验均证明了该方法的实用性。

关键词：有源电力滤波器模拟电路自适应低通滤波器谐波检测