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蒲公英提取物及其复合酵母培养物对奶牛隐形乳房炎的药效评价

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中国饲料 2024年第5期 166-171页

作者：彭清洁蔡大亮姜鹏黄鑫陈敬帮周迪张彦王苹苹胡龙飞戴晋军农业微生物资源发掘与利用全国重点实验室湖北宜昌443003 湖北省酵母功能湖北省重点实验室湖北宜昌443003 中国农业大学中兽医药创新中心北京100193

本研究旨在以患有隐性乳房炎的奶牛为试验对象,评价蒲公英提取物及其复合酵母培养物对奶牛隐性乳房炎的防治效果。试验选取28头同胎次泌乳牛,其中21头患有隐形乳房炎,以体细胞数量为核心指标,采用Excel随机分为A、B、C三个处理组,保证... 详细信息

本研究旨在以患有隐性乳房炎的奶牛为试验对象,评价蒲公英提取物及其复合酵母培养物对奶牛隐性乳房炎的防治效果。试验选取28头同胎次泌乳牛,其中21头患有隐形乳房炎,以体细胞数量为核心指标,采用Excel随机分为A、B、C三个处理组,保证各组隐性乳房炎患病牛的体细胞数无显著性差异;另7头健康奶牛作为阴性对照D组,每组7个重复,每个重复1头奶牛。试验开始,试验A、B两组分别在基础TMR日粮中添加蒲公英提取物40 g/(d·头)、(40 g蒲公英提取物+150 g酵母培养物)/(d·头),试验C、D两组饲喂基础TMR日粮,试验周期为11 d,分别在第0、6、11天采集牛奶和血液样本,检测牛奶体细胞数、血常规及乳品质等相关指标,同时记录每头牛泌乳量。结果显示:(1)体细胞数,试验第6天,与阳性对照C组相比,日粮添加蒲公英提取物以及蒲公英提取物复配酵母培养物组,牛乳中体细胞数分别下降63.2%和40.1%,二者体细胞数均达到阴性对照D组正常奶牛水平,其中蒲公英提取物组达到显著差异水平(P0.05);试验第11天,与阳性对照C组相比,日粮添加蒲公英提取物A组乳脂率差异不显著(P>0.05),而在日粮中添加蒲公英提取物复合酵母培养物B组乳脂率提升25%,表现出上升的趋势(0.05

关键词：隐形乳房炎酵母培养物蒲公英提取物体细胞单产水平乳品质

Seismic performance of recycled concrete-filled square steel tube columns

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 119-130页

作者： Chen Zongping Jing Chenggui Xu jinjun zhang Xianggang College of Civil Engineering and Architecture Guangxi University Nanning 530004 China Key Laboratory of Disaster Prevention and Structural Safety of Chinese Ministry of Education Guangxi University Nanning 530004 China

An experimental study on the seismic performance of recycled concrete-filled square steel tube （RCFST） columns is carried out. Six specimens were designed and tested under constant axial compression and cyclic lateral loading. Two parameters, replacement percentage of recycled coarse aggregate （RCA） and axial compression level, were considered in the test. Based on the experimental data, the hysteretic loops, skeleton curves, ductility, energy dissipation capacity and stiffness degradation of RCFST columns were analyzed. The test results indicate that the failure modes of RCFST columns are the local buckling of the steel tube at the bottom of the columns, and the hysteretic loops are full and their shapes are similar to normal CFST columns. Furthermore, the ductility coefficient of all specimens are close to 3.0, and the equivalent viscous damping coefficient corresponding to the ultimate lateral load ranges from 0.323 to 0.360, which demonstrates that RCFST columns exhibit remarkable seismic performance.

关键词： recycled concrete-filled square steel tube （RCFST） column replacement percentage cyclic loading seismicperformance

Identification of Lagrangian coherent structures in the turbulent boundary layer

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Science China(Physics,Mechanics & Astronomy) 2009年第2期52卷 248-257页

作者： PAN Chong WANG jinjun zhang Cao Institute of Fluid Mechanics Beijing University of Aeronautics and AstronauticsBeijing 100083China

Using Finite-Time Lyapunov Exponents (FTLE) method, Lagrangian coherent structures (LCSs) in a fully developed flat-plate turbulent boundary layer are successfully identified from a two-dimensional (2D) velocity field obtained by time-resolved 2D PIV measurement. The typical LCSs in the turbulent boundary layer are hairpin-like structures, which are characterized as legs of quasi-streamwise vor- tices extending deep into the near wall region with an inclination angle θ to the wall, and heads of the transverse vortex tube located in the outer region. Statistical analysis on the characteristic shape of typical LCS reveals that the probability density distribution of θ accords well with t-distribution in the near wall region, but presents a bimodal distribution with two peaks in the outer region, corresponding to the hairpin head and the hairpin neck, respectively. Spatial correlation analysis of FTLE field is im- plemented to get the ensemble-averaged inclination angle θ R of typical LCS. θ R first increases and then decreases along the wall-normal direction, similar to that of the mean value of θ. Moreover, the most probable value of θ saturates at y+=100 with the maximum value of about 24°, suggesting that the most likely position where hairpins transit from the neck to the head is located around y+=100. The ensem- ble-averaged convection velocity Uc of typical LCS is finally calculated from temporal-spatial correla- tion analysis of FTLE field. It is found that the wall-normal profile of the convection velocity Uc(y) ac- cords well with the local mean velocity profile U(y) beyond the buffer layer, evidencing that the down- stream convection of hairpins determines the transportation properties of the turbulent boundary layer in the log-region and beyond.

关键词： turbulent boundary layer coherent structures vortex identification scheme finite-time Lyapunov exponents hairpin-like vortices

Preparation of hydroxyapatite ceramic through centrifugal casting process using ultra-fine spherical particles as precursor and its decomposition at high temperatures

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Journal of Advanced Ceramics 2012年第1期1卷 60-65页

作者： Yanjie zhang jinjun LU Shengrong YANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Graduate School of the Chinese Academy of Sciences Beijing 100039China

Ultra-fine hydroxyapatite(HAp)powder with a diameter of about 10 nm was used as precursor for preparation of HAp ceramic.The precursor hydroxyapatite was single phase and highly crystallized without any additional thermal treatment.Highly densified HAp ceramic was fabricated through centrifugal infiltration casting(CIC),followed by pressureless sintering.The relative densities of compacts prepared at 1100°C and 1200°C were 77.8%and 94.1%,respectively.SEM micrographs of HAp ceramic sintered at 1100°C showed a porous microstructure with a grain size of 1μm.HAp ceramic fabricated at 1200°C revealed a dense microstructure with nano-sized sphericalα-TCP distributed at grain boundaries and triple points.The mechanism of decomposition from HAp toα-TCP at 1200°C was discussed on the basis of SEM,XRD and FTIR results.

关键词： hydroxyapatite bioceramics Centrifugal Infiltration Casting pressureless sintering

The effect of actuation frequency on the plasma synthetic jet

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Science China(Technological Sciences) 2011年第11期54卷 2945-2950页

作者： zhang PanFeng DAI ChenFeng LIU AiBing WANG jinjun Institute of Fluid Mechanics Beijing University of Aeronautics and Astronautics Beijing 100191 China Key Laboratory of Fluid Mechanics Ministry of Education Beijing 100191 China

The flow induced by plasma synthetic jet actuator was simulated through solving the Reynolds-averaged Navier-Stokes equations augmented by body force phenomenological plasma model.The effect of actuation frequency on the plasma synthetic jet was examined by case study.The numerical results present that with the actuation frequency increasing,the stream-wise distance of the adjacent vortex pairs induced by the actuator decreases monotonically,which is the same as the situation of the velocity fluctuations field caused by the vortex pairs.When the actuation frequency is 60 Hz,the vortex pairs formed during the adjacent actuation periods merge together quickly,and the flow structure in the downstream region is more close to that of the steady case.The actuation frequency has no visible influence on the time-averaged flow field of plasma synthetic jet.However,when the actuation frequency is relatively low(f<40 Hz),the momentum flux close to the actuator increases with the actuation frequency increasing,which is contrary to the situation in the far field from the wall.

关键词：等离子体合成驱动频率合成射流 Stokes方程执行机构雷诺平均数值结果单调下降

Review of zero-net-mass-flux jet and its application in separation flow control

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Science China(Technological Sciences) 2008年第9期51卷 1315-1344页

作者： zhang PanFeng WANG jinjun FENG LiHao Institute of Fluid Mechanics Beijing University of Aeronautics and AstronauticsBeijing 100191China

Since the zero-net-mass-flux (ZNMF) jet was first used as a laboratory flow control method in 1990's, it has attracted much attention. The ZNMF jet has unique features such as compact actuator, no requirement for external air supply, complex piping, etc., and becomes a hot topic research subject in fluid mechanics. This review introduces the state of the art in the development of ZNMF jet in the quiescent fluid, the interaction of the ZNMF jet with the cross flow and its application in the separation flow control. The evolution of the vortex ring/pair and the spacial flow structure of the ZNMF in quicent fluid or cross flow are presented, as well as the key parameter effects. At last, the applications of ZNMF jet in the wake control of the circular cylinder, the separation control on the airfoil and the aerodynamic force or moment control on MAV/UAV are presented.

关键词： zero-net-mass-flux jet quiescent fluid cross flow separation control

Strong motion characteristics of the M_w 6.6 Lushan earthquake,Sichuan,China——an insight into the spatial difference of a typical thrust fault earthquake

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 203-216页

作者： Hu jinjun zhang Wenbo Xie Lili zhang Qi Jiang Zhijun Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering Mechanics China Earthquake Administration College of Earth Science University of Chinese Academy of Science School of Civil Engineering Harbin Institute of Technology

Near-field strong ground motions are useful for engineering seismology studies and seismic design, but dense observation networks of damaging earthquakes are still rare. In this study, based on the strong-motion data from the M w 6.6 Lushan earthquake, the ground motion parameters in different spatial regions are systematically analyzed, and the contributions from different effects, like the hanging-wall effect, directivity effect, and attenuation effect are separated to the extent possible. Different engineering parameters from the observed ground motions are compared with the local design response spectra and a new attenuation relation of Western China. General results indicate that the high frequency ground motion, like the peak ground acceleration, on two sides of the fault plane is sensitive to the hanging-wall effect, whereas the low frequency ground motion, like the long period spectral acceleration, in the rupture propagation direction is affected by the directivity effect. Moreover, although the M w 6.6 Lushan earthquake is not a large magnitude event, the spatial difference of ground motion is still obvious; thus, for a thrust faulting earthquake, in addition to the hanging effect, the directivity effect should also be considered.

关键词： Lushan earthquake near-fi eld ground motion direct

Investigation of Evaporated Fragments in Intermediate Energy Heavy Ion Collisions

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Chinese journal of nuclear physics 1997年第4期19卷 216-219页

作者： Liu, Fuhu zhang, jinjun Shanxi Teachers' Univ Linfen China

The reactions induced by intermediate energy heavy ions are investigated.The evap-orated fragment multiplicity and excitation energy distributions are calculated and comparedwith the experimental data of the reaction ... 详细信息

关键词： Intermediate energy heavy ion Collisions Evaporated fragment Multiplicity Excitation energy

酵母培养物替代鱼粉对黄颡鱼生长性能、血清生化、体成分、抗氧化及免疫力的影响

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中国饲料 2024年第8期 168-172页

作者：王钦易建华王辉宋庆洋敖慧玲曹诗宜别汉晴张彦覃先武戴晋军农业微生物资源发掘与利用全国重点实验室湖北宜昌443003 湖北省酵母功能湖北省重点实验室湖北宜昌443003

为研究酵母培养物替代鱼粉对黄颡鱼生长性能、血清生化、体成分、抗氧化及免疫能力的影响,选用初始体重为(25.00±0.15)g的黄颡鱼600尾,随机分为2组,每组3个重复,每个重复100尾鱼,以基础饲料为对照组(CK),添加酵母培养物1∶1替代基础饲... 详细信息

为研究酵母培养物替代鱼粉对黄颡鱼生长性能、血清生化、体成分、抗氧化及免疫能力的影响,选用初始体重为(25.00±0.15)g的黄颡鱼600尾,随机分为2组,每组3个重复,每个重复100尾鱼,以基础饲料为对照组(CK),添加酵母培养物1∶1替代基础饲料中鱼粉为试验组(LYF),饲养42?d后采样分析。结果显示:与对照组相比,酵母培养物能提高黄颡鱼的相对诱食率10.43%(P 0.05);能显著降低黄颡鱼血清谷草转氨酶(AST)活性(P <0.05),降低25.73%;显著降低黄颡鱼血清丙二醛(MDA)含量(P <0.05),降低71.80%;试验组黄颡鱼血清溶菌酶(LZM)和碱性磷酸酶(AKP)活性显著增加(P <0.05),分别提高61.22%和65.63%。由此得出,酵母培养物1∶1替代鱼粉不会影响黄颡鱼的生长性能、肝脏健康、体成分,还能提高黄颡鱼的抗氧化能力和免疫力。

关键词：酵母培养物替代鱼粉黄颡鱼生长性能血清生化体成分抗氧化免疫