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Detection of lntraceUular Proteins and Biomarkers Using Modified Silica Nanoparticles and Flow Cytometry In vitro

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Chemical Research in Chinese Universities 2018年第2期34卷 229-234页

作者： YU Yang MA wei YU Lina ZHOU Shuyuan zhu Guangshan SHI wei Department of Sports and Health Guangzhou Institute of Physical Education Guangzhou 510500 P. R. China Key Laboratory for Molecular Enzymology and Engineering Ministry of Education College of Life Science Jilin Universily Changchun 130012 P. R. China China-Japan Union Hospital Jilin University Changchun 130033 P. R. China Key Laboratory of Oral Medicine Guangzhou Institute of Oral Disease Stomatology Hospital of Guangzhou Medical University Guangzhou 510140 P. R. China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 R R. China Key Laboratory of Polyoxometalate Science Ministry of Education Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

In this paper, antibody-modified silica nanoparticles were successfully synthesized, and their average di- ameter was （1094-9） nm. These particles were mixed with cell extracts to target a protein, then, an antibody labeled with fluorescein isothiocyanate（FITC） was added to form FITC-labeled nanoparticle complexes and the product was analyzed using flow cytometry. The results confirm that the intracellular proteins and biomarkers were precisely and sensitivity detected by the novel method in vitro. The FITC intensity of Akt antibody-conjugated particles was in- creased ≥ 10-fold compared with that of control samples in MCF-7 cells. Furthermore, it can also simultaneously measure several proteins when modified with different antibodies.

关键词： Silica nanoparticle Flow cytometry Intracellular protein Biomarker

Lock threshold deterioration induced by antenna vibration and signal coupling effects in hypersonic vehicle carrier tracking system of Ka band

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Chinese Journal of Aeronautics 2018年第4期31卷 776-781页

作者： Congying zhu Lei SHI Xiaoping LI Yanming LIU wei AI School of Aerospace Science and Technology Xidian University

The envelope of a hypersonic vehicle is affected by severe fluctuating pressure, which causes the airborne antenna to vibrate slightly. This vibration mixes with the transmitted signals and thus introduces additional multiplicative phase noise. Antenna vibration and signal coupling effects as well as their influence on the lock threshold of the hypersonic vehicle carrier tracking system of the Ka band are investigated in this study. A vibration model is initially established to obtain phase noise in consideration of the inherent relationship between vibration displacement and electromagnetic wavelength. An analytical model of the Phase-Locked Loop（PLL）, which is widely used in carrier tracking systems, is established. The coupling effects on carrier tracking performance are investigated and quantitatively analyzed by imposing the multiplicative phase noise on the PLL model. Simulation results show that the phase noise presents a Gaussian distribution and is similar to vibration displacement variation. A large standard deviation in vibration displacement exerts a significant effect on the lock threshold. A critical standard deviation is observed in the PLL of Binary Phase Shift Keying（BPSK） and Quadrature Phase Shift Keying（QPSK） signals. The effect on QPSK signals is more severe than that on BPSK signals. The maximum tolerable standard deviations normalized by the wavelength of the carrier are 0.04 and 0.02 for BPSK and QPSK signals,respectively. With these critical standard deviations, lock thresholds are increased from à12 andà4 d B to 3 and à2 d B, respectively.

关键词： Antenna vibration Carrier tracking performance Lock threshold Phase locked loop Tracking Telemetry and Command(TT&C) signals

Incorporating Convexity in Bond Portfolio Immunization Using Multifactor Model:A Semidefinite Programming Approach

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Journal of the Operations Research Society of China 2018年第1期6卷 3-23页

作者： wei zhu Cai-Hong Zhang Qian Liu Shu-Shang zhu Department of Finance and Investment Sun Yat-Sen Business SchoolSun Yat-Sen UniversityGuangzhou 510275China Ping An Securities Company Ltd Beijing 100033China

Bond portfolio immunization is a classical issue in finance. Since Macaulaygave the concept of duration in 1938, many scholars proposed different kinds of duration immunization models. In the literature of bond portfolio immunization usingmultifactor model, to the best of our knowledge, researchers only use the first-orderimmunization, which is usually called as duration immunization, and no one hasconsidered second-order effects in immunization, which is well known as “convexity” in the case of single-factor model. In this paper, we introduce the second-orderinformation associated with multifactor model into bond portfolio immunization andreformulate the corresponding problems as tractable semidefinite programs. Bothsimulation analysis and empirical study show that the second-order immunization strategies exhibit more accurate approximation to the value change of bonds and thusresult in better immunization performance.

关键词： Immunization Duration Convexity Multifactor model Semidefinite programming

发酵桑枝叶粉对蛋鸡生产性能、蛋品质、肠道组织形态的影响

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草地学报 2024年第4期32卷 1259-1266页

作者：黄静赵娜郭万正金枫陈芳朱伟樊启文杜恩存陶文静黄少文魏金涛湖北省农业科学院畜牧兽医研究所动物胚胎工程及分子育种湖北省重点实验室湖北武汉430064 咸宁市农业科学院湖北咸宁437000

为探究发酵桑枝叶粉对蛋鸡生产性能、蛋品质、肠道组织形态的影响,试验选用36周龄蛋鸡360只,随机分为4组,对照组饲喂基础饲粮,试验组分别用3%,6%,9%发酵桑枝叶粉替代等量的基础饲粮。结果表明:与对照组相比,1—4周各试验组产蛋率显著降... 详细信息

为探究发酵桑枝叶粉对蛋鸡生产性能、蛋品质、肠道组织形态的影响,试验选用36周龄蛋鸡360只,随机分为4组,对照组饲喂基础饲粮,试验组分别用3%,6%,9%发酵桑枝叶粉替代等量的基础饲粮。结果表明:与对照组相比,1—4周各试验组产蛋率显著降低(P<0.05),5—8周各试验组不合格蛋率显著提高(P<0.05),9—12周3%发酵组不合格蛋率显著提高(P<0.05),6%和9%发酵组显著降低(P<0.05);第4周末各试验组鸡蛋蛋白高度、3%和9%发酵组哈氏单位、6%发酵组蛋壳厚度显著提高(P<0.05),第12周末各试验组蛋黄胆固醇含量显著降低(P<0.05);9%发酵组肝脏指数、各试验组肝脏甘油三酯含量显著降低(P<0.05);3%和6%发酵组空肠绒毛高度、6%和9%发酵组回肠绒隐比显著增加(P<0.05)。本试验条件下,在蛋鸡饲粮中使用6%发酵桑枝叶粉(桑枝叶粉含量50%)最为适宜。

关键词：发酵桑枝叶粉蛋鸡生产性能蛋品质肠道组织形态

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Separation of Six Pyridoncarboylxic Acid Derivatives by Micellar and Microemulsion Electrokinetic Chromatography

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Chinese Chemical Letters 2001年第2期12卷 155-156页

作者： jian De LU wei YUAN Xiao Yun FU Analytical and Testing Center Yuquan CampusZhejiang UniversityHangzhou 310027

Micellar and microemulsion electrokinetic chromatography (MEKC & MEEKC) separation of six closely structural pyridoncarboylxic acid derivatives were studied and compared Both anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant hexadecyl-trimethyl ammonium bromide: (CTAB) were used to form micellar and microemulsion as pseudostation phases, respectively. The effects of the separation conditions on retention time and selectivity were studied. Good resolutions were obtained in selected systems. indicating that there is markably different selectivity between SDS and CTAB systems.

关键词： Micellar microemulsion electrokinetic chromatography

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基于FPGA的X光机焦点测量仪系统设计

中国测试 2024年第8期50卷 137-143页

作者：敖子逸杨建万清周伟袁婷萱范浩成都理工大学核技术与自动化工程学院四川成都610059 中国测试技术研究院四川成都610021 四川中测辐射科技有限公司四川成都610052

X光机的焦点尺寸是影响X射线成像质量的关键因素之一,针对X光机焦点尺寸测量方法繁琐、测量效率低等问题,文章提出一种以FPGA为核心控制芯片,狭缝法为测量原理的X光机焦点测量仪系统设计方案,通过线阵CCD传感器采集狭缝成像后的焦点信息... 详细信息

X光机的焦点尺寸是影响X射线成像质量的关键因素之一,针对X光机焦点尺寸测量方法繁琐、测量效率低等问题,文章提出一种以FPGA为核心控制芯片,狭缝法为测量原理的X光机焦点测量仪系统设计方案,通过线阵CCD传感器采集狭缝成像后的焦点信息,随后进行模数转换,并采用USB2.0传输方式将数据传输至上位机进行处理和计算。文章重点讨论线阵CCD、A/D转换和USB传输的驱动与时序设计,以及焦点尺寸的计算方法,该系统具有高精度、实时性低延迟的特点。实验结果表明,在对X光机大、小焦点尺寸各进行10次测量后,测量重复性分别为0.2808%和0.4779%,示值误差均在±0.15 mm范围内,这证明了该系统能够实现对X光机焦点尺寸的精准测量。

关键词： X光机焦点狭缝法焦点测量 FPGA 线阵CCD

Nozzle test system for droplet deposition characteristics of orchard air-assisted sprayer and its application

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International Journal of Agricultural and Biological Engineering 2014年第2期7卷 122-129,I0003页

作者： Zhai Changyuan Zhao Chunjiang Wang Xiu Li wei Li wei zhu Ruixiang College of Mechanical and Electronic Engineering Yangling 712100ShaanxiChina Northwest A&F University Yangling 712100ShaanxiChina National Engineering Research Centre for Information Technology in Agriculture Beijing 100097China

In order to obtain nozzle droplet deposition characteristics for sprayer mechanical design and variable spraying control algorithms,a nozzle droplet deposition characteristics test system for air-assisted spraying was *** test system can supply a stable wind site with precisely controlled air speed whose speed control ranges from 2 m/s to 16 m/s with maximum relative error of 4.5%.It can spray out a certain amount of liquid pesticide with adjustable spraying pressure which can be controlled with high precision while the maximum relative error is only 1.33%.The distribution of droplet deposition can be collected and measured by using the acquisition device and a pesticide deposition optical measurement *** experiment of two-dimensional nozzle flow measurement was carried *** results show that nozzle flow distribution is uniform and symmetric with“double-hump”shape in the spray ***-nozzle overlapped droplet deposition ranges from 85%to 116%relative to the *** nozzle droplet deposition experiment was *** experiment results show that in air-assisted spraying,the higher the wind speed,the less droplet deposition is affected by *** the wind speed is higher than 12 m/s and spraying distance is 0.80 m,droplet deposition is concentrated on the originally designated point and hardly affected by *** horizontal spray width becomes smaller with higher wind *** the wind speed is high,it can be considered that nozzle deposition only focuses on the nozzle center,if the position requirement is not very high in orchard spraying.

关键词： air-assisted spraying orchard sprayer flow distribution droplet deposition nozzle test system characteristics test system

Experimental investigation of the relation between the surface integrity and bending fatigue strength of carburized gears

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Science China(Technological Sciences) 2023年第1期66卷 33-46页

作者： CHEN DiFa zhu JiaZan LIU HuaiJu wei PeiTang MAO TianYu State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China China Gas Turbine Establishment Chengdu 710025China

Bending fatigue is an essential parameter that needs to be considered in the improvement process of the power density and reliability of gear drives. Quantitative relations among the manufacturing parameters, surface integrities, and fatigue performance are not clear, which seriously limits the effectiveness of an anti-fatigue design. For this work, tooth-bending fatigue tests of carburized gears with different surface integrities were performed using a pulsator. The effects of the manufacturing parameters and surface integrities on the gear fatigue, such as surface hardness and residual stress, were investigated. The experimental results revealed that due to the improvement of surface integrities after shot peening, the nominal bending stress number(fatigue limit) increased by 6.3%–31.1%, with an amplitude range of 39–143 MPa. A supervised learning algorithm of a random forest was implemented to determine the contribution of the surface hardness and surface residual stress to the nominal stress number. An empirical formula was proposed to predict the nominal stress number considering the surface integrities. The prediction error was less than 7.53%, as verified by several gear-bending fatigue tests. This provided theoretical support for the modern, anti-fatigue design of the gears.

关键词： carburized gear surface integrity bending fatigue design formula

Wire electrochemical machining with axial electrolyte flushing for titanium alloy

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Chinese Journal of Aeronautics 2013年第1期26卷 224-229页

作者： Qu Ningsong Fang Xiaolong Li wei Zeng Yongbin zhu Di College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Titanium and its alloys have found very wide application in aerospace due to their excellent characteristics although their processing is still a challenge. Electrochemical machining is an important issue in the fabrication of titanium and titanium alloys. Wire electrochemical machining （WECM） is mainly used for workpiece cutting under the condition of different thickness plates. It has a great advantage over wire electro-discharge machining, which is the absence of heat-affected zone around the cutting area. Moreover, the wire electrode in WECM could be used repetitively because it is not worn out. Thus, much attention has been paid to WECM. The effective way of removing electrolysis products is of importance to WECM. In this paper, the axial electrolyte flushing is presented to WECM for removing electrolysis products and renewing electrolyte. The Taguchi experiment is conducted to optimize the machining parameters, such as wire feedrate, machining voltage, electrolyte concentration, etc. Experimental results show that WECM with axial electrolyte flushing is a promising issue in the fabrication of titanium alloy （TC1）. The feasibility of multi-wire electrochemical machining is also demonstrated to improve the machining productivity of WECM.

关键词： Axial electrolyte flushing Electro machining Electrochemical machining Titanium alloy Wire electrochemical machining