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Identification and analysis of the inlet vortex of an axial-flow pump

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Journal of Hydrodynamics 2022年第2期34卷 234-243页

作者： Wen-peng Zhang li-jian shi Fang-ping Tang Zhuang-zhuang Sun Ye Zhang College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou225009China

Axial-flow pumps are widely employed in urban flood control and drainage pumping *** inlet vortex is one factor that seriously threaten the safe,stable and efficient operation of axial-flow pump *** this paper,the vortex recognition performances of two vortex identification methods,the Q—criterion and liutex methods,are compared based on an axial-flow pump,and the interactions between the impeller and vortex are explored.A flat plate vortex generator is installed in front of the impeller to continuously induce a stable *** numerical simulation results show that the liutex method can not only simultaneously identify strong and weak vortices but also reduce the influence of shear force at the *** vortex and the impeller influence each *** the influence of rotating blades,the vortex changes from a low frequency to the blade frequency,and the vortex significantly changes the tangential velocity inside the *** accuracy of the numerical simulation results is verified by experiments on the external and internal characteristics.

关键词： Axial-flow pump inlet vortex vortex identification vortex generator numerical simulation experiment

The antibody against a nuclear autoantigenic sperm protein can result in reproductive failure

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Asian Journal of Andrology 2009年第2期11卷 183-192页

作者： Min Wang jian-li shi Guo-Yan Cheng Yan-Qing Hu Chen Xu Department of Histology&Embryology Shanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Key Laboratory for Reproductive Medicine Shanghai 200025China

To study whether the antibody against the testis form of the nuclear autoantigenic sperm protein(tNASP)could result in reproductive failure,we successfully cloned and expressed a 339-bp cDNA fragment of mouse tNASP(mtNASP).Using mouse as a model,recombinant mtNASP(rmtNASP)and a synthetic peptide,human tNASP393-408(htNASP393-408),were investigated for their antifertility *** immunization with rmtNASP or the synthesized peptide raised high antibody titers in the immunized ***-egg binding and fusion assay were carried out in 8-10-week-old BALB/c ***-egg binding and in vitro fertilization of mouse oocytes were inhibited by co-incubation of zona-free mouse oocytes with capacitated mouse spermatozoa in the presence of varying concentrations of the antisera against *** was a significant antifertility effect in animals immunized with rmtNASP or the synthesized *** effect on fertility in the mice immunized with the synthesized peptide was *** data indicate that active immunization with rmtNASP antigen may induce a strong antibody response that causes an inhibition of fertility.

关键词： antifertility gene expression nuclear autoantigenic sperm protein(NASP) sperm-egg binding sperm-egg fusion

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一类“非常规”系统的仿真方法

系统仿真学报 2007年第23期19卷 5500-5505页

作者：田丰李侠李坚石贵州大学计算机科学与技术学院贵阳550025

精密机电元件可化为非线性"非常规"平面梁柱有限元系统。基于这个系统的共同特征,构造了这类"非常规"的通用数学模型及其迭加解法。基于不同的"非常规"条件,构造五类具体的迭加解法及同步约束算法。基于不同的系统特征,构造了三类具体... 详细信息

精密机电元件可化为非线性"非常规"平面梁柱有限元系统。基于这个系统的共同特征,构造了这类"非常规"的通用数学模型及其迭加解法。基于不同的"非常规"条件,构造五类具体的迭加解法及同步约束算法。基于不同的系统特征,构造了三类具体系统安装到工作过程的数学模型。采用"非常规"非线性有限元与正交回归设计相结合的方法,建立了表征系统工作状态及具体性能的拟合算式,并对仿真方法的精度和系统寿命进行了讨论。

关键词：非常规系统迭加解法数学模型仿真方法拟合算式

Effects of Chinese Herb Additive on Milk Yield and Anti-heat Stress Ability of Holstein Cows

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Animal Husbandry and Feed Science 2010年第2期2卷 38-40页

作者： ZHAO Zheng CHEN Xue-wen li shi-jian Department of Animal Science Guangxi Agricultural Vocational Technical College Nanning 530007 China Guangxi Royal Dairy Co. Ltd. Nanning 530007 China

[Objective] To explore the effects of Chinese herb additive on milk yield and anti-heat stress ability of Holstein diary cow. [Method] A total of 36 Holstein cows at same parity and with similar milk yield were randomly divided into three groups, namely, control group, Chinese medi- cine group I and Chinese medicine group I1. The cows in the Chinese medicine group I were fed basal diet containing 4% compound Chinese herb additive; those in the Chinese medicine group II were fed basal diet containing 3% compound Chinese herb additive; and those in the control group were fed common basal diet. All cows in the three groups were analyzed comparatively. [Result] Supplementing some compound Chinese herb ad- ditive into basal diet increased milk yield and anti-heat stress ability of Holstein cows, besides, it also decreased cow diseases like cow mastitis. The Chinese medicine group I generated the highest economic benefit of practical production. [ Conclusion] Supplementing Chinese herb additive in- to basal diet is an effective way to relieve heat stress and increase milk yield.

关键词： Chinese herb additive Holstein diary cow Milk yield Anti-heat stress

我国夏季奥运会优秀运动员成才过程的项群特征研究

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中国体育科技 2014年第6期50卷 12-18页

作者：李士建曲阜师范大学体育科学学院山东曲阜273165

通过对我国在第27～30届夏季奥运会334名获得奖牌运动员的成才过程进行分析,研究我国奥运会优秀运动员成才规律的项群特征。从时间变化特征来看,我国奥运会优秀参赛运动员的成才年龄普遍提前,男子业余训练年限、女子体能类项目地方队训... 详细信息

通过对我国在第27～30届夏季奥运会334名获得奖牌运动员的成才过程进行分析,研究我国奥运会优秀运动员成才规律的项群特征。从时间变化特征来看,我国奥运会优秀参赛运动员的成才年龄普遍提前,男子业余训练年限、女子体能类项目地方队训练年限、技能类项目国家队奥运前训练阶段年限显著延长。从时间结构特征来看可分为两类,类型一包括表现难美性项群等项目项群,表现为运动员成才历时较长,各阶段比例相对均衡;类型二包括同场对抗性项群等项目项群,表现为运动员成才历时较短,各阶段比例呈上升态势。从转项特征来看,总体转项成才率为21.1%,且女子项目高于男子;转项成才的主要方式为大类间转项和同群间转项,其中,大类间转项的曾训项目多为田径、游泳等体能主导类项目。

关键词：优秀运动员奥运会项群成才中国

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面向残障人士的基于眼动交互的绘画系统

电子学报 2011年第A3期39卷 163-167页

作者：李姗潘纲李石坚浙江大学计算机学院浙江杭州310027

本文建立了一个面向严重肢体残障人士的眼动交互绘画系统.为此,首先给出了眼动数据的预处理与分析方法;为减弱米达斯(Midas)接触问题对眼动行为判别的影响,提出了基于时域约束的注视点聚类算法,可提取出注视点判断用户当前的视点中心,... 详细信息

本文建立了一个面向严重肢体残障人士的眼动交互绘画系统.为此,首先给出了眼动数据的预处理与分析方法;为减弱米达斯(Midas)接触问题对眼动行为判别的影响,提出了基于时域约束的注视点聚类算法,可提取出注视点判断用户当前的视点中心,并据此进一步判断用户眼睛行为;针对眼动原始数据中的噪声影响,设计了窗口长度自适应的视点信号平滑处理方法,可减弱视点抖动产生的噪声,实现自由绘画较为平稳的绘画轨迹.在此基础上,设计并实现了基于ASL眼动仪的眼动交互式绘画系统.

关键词：眼动交互驻留时间眼睛行为

Practice of improving the hot blast temperature for the 2500 m^3 BF

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Baosteel Technical Research 2008年第2期2卷 31-35页

作者： li Yiwei shi jian＇ en Bao Lei Wang Yi Ironmaking Plant Stainless Steel Branch Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200431 China

A high blast temperature is an effective measure that improves pulverized coal injection （PCI）and energy consumption,decreases the cost of blast furnaces （BF）. Apart from using technology such as the increased vault temperature of the hot-blast stove, the increased temperature of the waste gas, the preheating of combustion air and gas, and fully closed mixed air valves, other measures, such as using an oxygen-enriched blast stove, burning high heating value converter gas, increasing the number of stove changes to reduce the time needed for stove blasts, were taken to increase the blast temperature of the 2 500 m3 BF in recent years. The blast temperature of the 2 500 m3 BF was continuously increased in these years. The monthly average temperature of the 2 500 m3 BF reached 1 158℃, with the highest blast temperature reaching 1 195 ℃ in 2006. This technique of increased blast temperatures has reached an advanced level in China.

关键词： hot blast stove high blast temperature oxygen-enriched stove converter gas

CdS/CdMoO_4空心微球复合材料的化学沉淀法制备及光催化性能

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环境化学 2018年第10期37卷 2283-2290页

作者：李坚石先阳安徽大学资源环境与工程学院合肥230601

采用化学沉淀法制备了CdS/CdMoO_4空心微球复合材料,通过透射电镜(TEM)、扫描电镜(SEM)、X射线衍射仪(XRD)、X射线光电子能谱分析仪(XPS)、荧光光谱(PL)等对该复合材料的结构、形貌及其光学和可见光光催化性能进行了表征.结果表明,所制... 详细信息

采用化学沉淀法制备了CdS/CdMoO_4空心微球复合材料,通过透射电镜(TEM)、扫描电镜(SEM)、X射线衍射仪(XRD)、X射线光电子能谱分析仪(XPS)、荧光光谱(PL)等对该复合材料的结构、形貌及其光学和可见光光催化性能进行了表征.结果表明,所制备的CdS/CdMoO_4复合材料具有明显的空心微球结构,且其直径在1μm左右,表现出优异的吸附性能.此外,CdMoO_4良好的光生电子转移性能使得CdS/CdMoO_4空心微球复合材料亦表现出良好的催化性能和光稳定性.该复合材料在60 min内对亚甲基蓝光降解率达到了98.7%,且3次光催化实验重复性好.

关键词： CdS/CdMoO4 空心微球光催化

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun Fu Hong-Wei li jian-Hong shi Tan li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs