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山羊产后乳中孕酮浓度的变化

核农学报 1989年第1期3卷 53-60页

作者：郭大智刘显义陈发菊宋雪华苏全君王开荣蔡学林刘相模徐刚毅四川农业大学同位素室四川农业大学山羊育种教研室

应用放射免疫分析和竞争蛋白结合分析法测定了成都麻羊、莎能羊及其杂交一代母羊产后四月内的乳中孕酮浓度变化。供试动物在试验期间的孕酮浓度一般保持基础水平,约有87.2％(成都麻羊)、94.4％(莎能羊)和93.9％(杂交羊)的测值在10ng/ml... 详细信息

应用放射免疫分析和竞争蛋白结合分析法测定了成都麻羊、莎能羊及其杂交一代母羊产后四月内的乳中孕酮浓度变化。供试动物在试验期间的孕酮浓度一般保持基础水平,约有87.2％(成都麻羊)、94.4％(莎能羊)和93.9％(杂交羊)的测值在10ng/ml以下。孕酮浓度升高发生1—5次,较行为发情次数为多。第一次孕酮浓度升高发生在产后26—67天(成都麻羊)、19—52天(莎能羊)和39—122天(杂交羊)期间。产后五天内初乳中的孕酮含量平均为每日2—4ng。

关键词：山羊孕酮放射免疫测定 CPBA

A Dead-Beat Control Method for APF Based on Mixed Prediction

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A Dead-Beat Control Method for APF Based on Mixed Prediction

高原重载牵引汽车电动轮驱动系统减速装置优化设计

第26届中国控制与决策会议

作者： Han Wei Wang dazhi Li Yunlu liu Zhen Institute of Electric Power System and Motor Drives School of Information Science & EngineeringNortheastern University College of physics and Electronic information Inner Mongolia University for Nationalities

ISBN: (纸本)9781479937066

Affected by the signal sampling, processing and executing delays, the conventional dead-beat control is actually a one-step-delay control. To solve this problem, an improved dead-beat control method is discussed in this paper. The method calculates the output average voltage one sampling period earlier using the prediction reference current value two sample instants in advance and the inverter output prediction current value one sample instant in advance, and then the "real" dead-beat control will be achieved. A mixed prediction strategy is also proposed considering both the steady and dynamic states of the load, which will make the control method process a better precision and dynamic characteristic. At last, simulation and experiment prove that the improved dead-beat control in this scheme can compensate the harmonic current very effective both in the steady and dynamic conditions.

关键词： Dead-beat control Mixed prediction Adaptive forward linear prediction Active power filter

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青海科技 2023年第2期30卷 166-172页

作者：张艺伟伊成山刘大智王云龙汪永姣苏妃青海民族大学土木与交通工程学院西宁810007

文章从对重型牵引汽车电动轮减速装置优化角度出发,分析减速装置的载荷条件以及工作状况等因素,将NGW行星齿轮减速器的体积、效率以及齿轮重合度作为目标函数,根据可靠性理论对减速装置进行优化设计。通过把齿轮的轮齿齿面接触疲劳强度... 详细信息

文章从对重型牵引汽车电动轮减速装置优化角度出发,分析减速装置的载荷条件以及工作状况等因素,将NGW行星齿轮减速器的体积、效率以及齿轮重合度作为目标函数,根据可靠性理论对减速装置进行优化设计。通过把齿轮的轮齿齿面接触疲劳强度与齿根弯曲疲劳强度的校核结合可靠性理论使用到优化设计中的约束条件中,计算减速装置零部件参数的最优解,使得在质量最轻、体积最小的同时传动效率依旧可靠。通过一系列的优化设计,使得减速装置可以满足牵引汽车电动轮模块的特殊要求,也为今后重型牵引汽车电动化设计以及相关研究提供一定的参考依据,助力创建绿色、节能、低碳、环保的现代交通运输体系。

关键词：电动轮驱动系统 NGW行星齿轮减速器重型牵引汽车可靠性优化设计

Effect of withdrawal rate on microstructure of a hypoeutectic Al-Si alloy by low superheat DC casting

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China Foundry 2013年第3期10卷 172-175页

作者： Zhao dazhi liu Fang Yu Fuxiao Hong Tao Zuo Liang Department of Metal Forming School of Materials and Metallurgy Northeastern University Key Lab. for Anisotropy and Texture of Materials (Ministry of Education) Northeastern University Xinjiang Joinworld Co. Ltd.

To obtain the billet with homogeneous and spheroidized primary grains is the key step in the semi- solid forming process. Among the semi-solid billet preparation methods, the process of low-superheat direct chill （DC） casting is simpler and more effective. In this study, the billets of AISi7Mg alloy were prepared by low- superheat DC casting at various withdrawal rates. The effect of withdrawal rate on the surface quality of the billets was investigated, and the evolution mechanism of the microstructural morphology in the billets was analyzed. The results show that the periodic corrugations and a large quantity of fine shrinkage pits appear in the billet surface when the withdrawal rate is 100 ***-1, and the above defects in the billet surface can be eliminated completely when the withdrawal rate is above 150 ***-1. But when the withdrawal rate is too fast （250 ***-1）, the primary a grains, except the ones in the billet center, have not enough time for ripening due to the high silidification rate, and will solidify as the dendrite structure. When the withdrawal rate is between 150 - 200 ***-1, the dendritic growth of the primary a grains is effectively inhibited, and a billet of AISi7Mg alloy with a smooth surface and homogeneous, fine, non-dendritic grains can be obtained.

关键词： direct chill casting AlSi7Mg alloy withdrawal rate

Fabrication of micro/nano-structures by electrohydrodynamic jet technique

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Frontiers of Mechanical Engineering 2017年第4期12卷 477-489页

作者： dazhi WANG Xiaojun ZHAO Yigao LIN Tongqun REN Junsheng LIANG Chong liu Liding WANG Key Laboratory for Micro/Nano Technology and System of LiaoningProvince Dalian University of Technology Dalian 116024 China Key Laboratory for Precision and Non-traditional MachiningTechnology of the Ministry of Education Dalian University ofTechnology Dalian 116024 China

Electrohydrodynamicjet （E-Jet） is an approach to the fabrication of micro/nano-structures by the use of electrical forces. In this process, the liquid is subjected to electrical and mechanical forces to form a liquid jet, which is further disintegrated into droplets. The major advantage of the E-Jet technique is that the sizes of the jet formed can be at the nanoscale far smaller than the nozzle size, which can realize high printing resolution with less risk of nozzle blockage. The E-Jet technique, which mainly includes E-Jet deposition and E-Jet printing, has a wide range of applications in the fabrication ofmicro/nano-structures for micro/nano-electromechanical system devices. This tech- nique is also considered a micro/nano-fabrication method with a great potential for commercial use. This study mainly reviews the E-Jet deposition/printing fundamentals, fabrication process, and applications.

关键词： electrohydrodynamic jet deposition electro-hydrodynamic jet printing micro/nano-structures film

An Evolutionary Adaptive System for Prediction of Strategy Influence:A Case Study of Government Regulation Guided Brand Innovation

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Complex System Modeling and Simulation 2022年第3期2卷 197-212页

作者： Jiali Lin Qiaomei Li Guangsheng Lin Zhihui He dazhi Jiang Hao liu Business School Shantou UniversityShantou 515063China Department of Computer Science Shantou UniversityShantou 515063China

Decision making is one of the common human *** in complex,interactive,and dynamic systems,it is extremely important to make decisions scientifically because the influence of the behavior after decision making is generally *** predictability of behavior influence is an effective way to improve the scientific decision *** a new branch of computing,computational experiment is an emerging management method for research on complex *** this paper,based on particle swarm intelligence,an evolutionary adaptive system model of brand innovation in the toy industry cluster is *** imitating the evolution process of the complex adaptive system,this method is helpful to analyze the impact of the management behavior brought to simulation system,predict the management behavior in real world,and finally choose the best management *** simulation tried to figure out the affection of government regulation strategies and provide corresponding assessments and recommendations,which gives a new solution to assist the government to effectively judge the influence of the macro policy,as well as provides a new way of thinking of the related intelligent decision making.

关键词： decision making behavior influence computational experiment evolution adaptive system brand innovation

Novel Flow Field with Superhydrophobic Gas Channels Prepared by One-step Solvent-induced Crystallization for Micro Direct Methanol Fuel Cell

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Nano-Micro Letters 2015年第2期7卷 165-171页

作者： Junsheng Liang Kuanyao liu Shouzuo Li dazhi Wang Tongqun Ren Xiaoying Xu Ying Luo Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of Technology Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology

The CO2-induced capillary blocking in anode flow field is one of the key adverse factors to reduce the performance of a micro-direct methanol fuel cell(l DMFC). In order to solve this problem, new polycarbonate(PC) flow field plates with nested arrangement of hydrophilic fuel channels and superhydrophobic gas channels were designed,fabricated, and tested in this work. The gas channels were treated with solvent-induced crystallization using acetone solution. The superhydrophobicity with 160° water contact angle and 2° tilting angle was obtained on the PC substrates. A dummy cell using hydrogen peroxide decomposition reaction and a test loop were separately set up to evaluate the flow fields' performance. It was found that a 37 % pressure drop decrease can be obtained in the new serpentine flow field compared with that of the conventional one. The benefit of the new flow field to remove gas bubbles was also confirmed by an in situ visualization study on the dummy cell. Results show that the auxiliary superhydrophobic gas channels can speed up the discharge of the gas bubbles from the flow field, which will in turn improve the l DMFC performance.

关键词： Fuel cell Flow field Superhydrophobic Solvent-induced crystallization

Provenance System Analysis of the Nantun Formation of the Huhehu Sag in Hailar Basin

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 189-198页

作者： LI Junhui MENG Qi'an LU Shuangfang ZHU Defeng WU Haibo liu He ZHANG dazhi Exploration and Development Research Institute Daqing Oilfield Company LimitedDaqing 163712China Northeast Petroleum University College of Earth ScienceDaqing 163318China

Huhehu Sag is a new battlefield for the future oil and gas exploration in the Hailar Basin. At present, exploration of this area stays at a low level and the understanding of the provenance system of the Nantun Formation is comparatively weak. So, to carry out the detailed depiction of the provenance system in the study area is significant for the sedimentary system reconstruction, for the prediction of reservoir distribution and favorable areas. Based on comprehensive analysis of paleogeomorphy, light-heavy mineral and seismic reflection features, sandstone thickness and sandstone percentage, this paper analyzes in detail the provenance system of the Nantun Formation in Huhehu Sag from various angles and levels. It shows that provenances of the Huhehu Sag mainly originated from the eastern Xilinbeier Salient and western Bayan Mountain Uplift. The provenances surrounding the lake basin converged to the center of the basin, among which, the steep slope belt and the gentle slope belt are the main provenances, and the southern uplift is a secondary one. The distribution framework of the provenance fundamentally determines the distribution rules of the depositional system and its sand body developing during the Nantun period.

关键词： Huhehu Sag Nantun Formation provenance analysis sedimentary system

A novel sprayable thermosensitive hydrogel coupled with zinc modified metformin promotes the healing of skin wound

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Bioactive Materials 2023年第2期20卷 610-626页

作者： Zhengwei liu Wanze Tang Jiayi liu Yingying Han Qinnan Yan Yuechao Dong Xiaomei liu dazhi Yang Guixing Ma Huiling Cao Department of Biochemistry School of MedicineSouthern University of Science and TechnologyGuangdong Provincial Key Laboratory of Cell Microenvironment and Disease ResearchShenzhen Key Laboratory of Cell MicroenvironmentShenzhen518055China Southern University of Science and Technology Shenzhen518055China Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen518055China The First Affiliated Hospital Southern University of Science and TechnologyShenzhen518055China

A novel sprayable adhesive is established(ZnMet-PF127)by the combination of a thermosensitive hydrogel(Pluronic F127,PF127)and a coordination complex of zinc and metformin(ZnMet).Here we demonstrate that ZnMet-PF127 potently promotes the healing of traumatic skin defect and burn skin injury by promoting cell proliferation,angiogenesis,collagen ***,we find that ZnMet could inhibit reactive oxygen species(ROS)production through activation of autophagy,thereby protecting cell from oxidative stress induced damage and promoting healing of skin *** complex exerts better effects on promoting skin wound healing than ZnCl2 or metformin *** complex also displays excellent antibacterial activity against Staphylococcus aureus or Escherichia coli,which could reduce the incidence of skin wound ***,we demonstrate that sprayable PF127 could be used as a new drug delivery system for treatment of skin *** advantages of this sprayable system are obvious:(1)It is convenient to use;(2)The hydrogel can cover irregular skin defect sites evenly in a liquid *** combination with this system,we establish a novel sprayable adhesive(ZnMet-PF127)and demonstrate that it is a potential clinical treatment for traumatic skin defect and burn skin injury.

关键词： Thermosensitive hydrogel Skin wound ZnMet-PF127 Reactive oxygen species(ROS) Autophagy