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A Simplified Formulation to Estimate Influence of Gearbox Parameters on the Rattle Noise

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Sound & Vibration 2019年第2期53卷 38-49页

作者： jidong zhang Wentao Sui Jaspreet Dhupia School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore639798Singapore School of Mechanical Engineering Shandong University of TechnologyZibo255000China Department of Mechanical Engineering University of AucklandAuckland1010New Zealand

Occurrence of gear rattle in transmission systems can result in severe vibration and noise,which in applications such as automobiles is an important source of user *** a result,the reduction of the rattling noise has attracted lot of *** rattling noise level is affected by several gearbox parameters,an understanding of which is essential to prevent the expensive design modifications at later stages of product *** develop such understanding at the gearbox design stage,this paper analytically evaluates the gear parameters’effect on the root mean square of the wheel gear acceleration under idling condition,which is known to be linearly correlated to the rattling noise ***,this evaluation allows for an investigation of the gear parameters’influence on the rattling noise as *** method is then verified by comparing the analytical results with the simulation results from a dynamic model built in SIMPACK as well as previously published experimental ***,the proposed analytical evaluation method can optimize the gearbox specifications at the design stage to reduce the gear rattle noise level.

关键词： Rattle noise gear parameter analytical evaluation backlash dynamic model

生物质炭和有机肥配施对苹果重茬育苗地土壤理化性质和微生物群落特征的影响

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中国农业科技导报 2024年第8期26卷 213-222页

作者：张继东张亚雄程伟蒲莉柳路行王亚明甘肃林业职业技术学院甘肃天水741020

为研究生物质炭和有机肥配施对连作苹果育苗地的改良效果,以连作5年的苹果育苗地为研究对象,采用高通量测序技术结合土壤理化性质分析,探究不同配比生物质炭和有机肥配施对苹果根际土壤理化性质和微生物群落结构的影响。结果表明,生物... 详细信息

为研究生物质炭和有机肥配施对连作苹果育苗地的改良效果,以连作5年的苹果育苗地为研究对象,采用高通量测序技术结合土壤理化性质分析,探究不同配比生物质炭和有机肥配施对苹果根际土壤理化性质和微生物群落结构的影响。结果表明,生物质炭和有机肥配施处理后土壤中养分含量显著增加,土壤pH和电导率显著上升。其中以600kg·hm^(-2)生物质炭配施有机肥处理土壤的速效养分含量显著增加,其土壤全氮、碱解氮、速效磷、速效钾和有机碳含量分别显著增加15.06%、27.03%、61.32%、51.55%和20.18%。此外,生物质炭和有机肥处理提高了土壤中细菌群落的多样性和丰度,降低了真菌群落的多样性和丰度,使土壤中有益菌属的丰度显著增加。相关性分析表明,土壤有机碳、速效钾和碱解氮含量对土壤中细菌群落特征影响显著;而真菌群落特征主要受土壤全氮、有机碳和速效钾含量的影响。综上,生物质炭和有机肥配施对苹果育苗地连作障碍具有一定的缓解作用,可改善土壤的微环境,提高土壤质量。

关键词：苹果连作障碍生物质炭土壤理化性质微生物群落特征

Corrosion Behavior of Mg-Zn-Y Alloy with Long-period Stacking Ordered Structures

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Journal of Materials Science & Technology 2012年第12期28卷 1157-1162页

作者： Jinshan zhang jidong Xu Weili Cheng Changjiu Chen Jingjing Kang College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China

Mg-Zn-Y alloys with long-period stacking ordered structures were prepared by an ingot casting method. The corrosion performance of Mg-Zn-Y alloys was studied by combining gas-collecting test, immersion test and electrochemical measurements in order to determine the corrosion rate and mechanism of the alloys. The results showed that the volume fraction of Mg（12）YZn phase increased and the shape of the Mg（12）YZn phase changed from discontinuous to continuous net-like with increasing Zn and Y content. The corrosion rate of the alloys greatly depended on the distribution and volume fraction of the Mg（12）YZn phase. Corrosion products appeared at the junction of Mg phase and Mg（12）YZn phase, indicating that the Mg（12）YZn phase accelerated galvanic corrosion of Mg matrix. Mg（97）Zn1Y2 alloy shows the lowest corrosion rate due to the continuous distribution of Mg（12）YZn phase.

关键词： Mg-Zn-Y alloy Long-period stacking ordered (LPSO) structure Micro-galvanic corrosion Mg(12)YZn phase Corrosion behavior

A High Selective Chemiluminescent Probe Derived from Iso-luminol Enabling High Sensitive Determination of Ferrous Ions in the Environmental Waters

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Chinese Journal of Chemistry 2021年第11期39卷 2967-2972页

作者： Shenghai zhang Yalin Shi Jiawang Deng jidong zhang Mengqi Cheng Geting Yu Quality Supervision and Inspection Centre of Se-enriched Food of Shaanxi Province School of Chemistry&Chemical EngineeringAnkangUniverisityAn'kangShaanxi725000 China Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'anShaanxi710119 China

A new chemiluminescence(CL)reagent named 4-amino-5-thiocyanato-phthalyl-hydrazine(iso-luminol-SCN)is synthesized by the bromide-mediated substitution reaction of iso-luminol with sodium thiocyanate in dimethyl formamide(DMF)at room *** CL is observed for iso-luminol-SCN oxidized by hydrogen peroxide(H2O2)in the presence of Fe^(2+),with the CL intensity strongly depending on the concentration of Fe^(2+)and being hardly interferred by other common metal *** on this fact,a flow injection CL method is established for the high sensitive and selective determination of Fe^(2+).The CL intensity was linearly correlated with the concentration of Fe^(2+)in the range of 1.0×10^(–8) mol·L^(-1) to 1.0×10^(–5) mol·L^(-1) following the equation CLnet=166.3c+57.7(c,×10^(–6) mol·L^(-1);n=7;R2=0.9988).The detection limit is calculated to be 3.2×10–9 mol·L^(-1) Fe^(2+)based on the 3S0/K *** relative standard deviation(RSD)was 3.7%for 1.0×10^(–6) mol·L^(-1) Fe^(2+)(n=11),a support for the precision of Fe^(2+)*** recoveries of Fe^(2+)were obtained in the range of 98.8%—101.6%in three real water samples,showing the applicability and reliability by the proposed *** possible CL mechanism is proposed based on the kinetic characteristic of the CL reaction and the CL spectrum.

关键词： Chemiluminescence probe Synthesis design Ferrous ions Analytical method Environmental waters

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芦山县暴雨特征分析

四川水利 2024年第1期45卷 65-69页

作者：瑚东涵张文娟张继东四川省雅安水文水资源勘测中心四川雅安625000

基于2013-2022年芦山站、太平站、保卫站降水整编资料,对芦山县暴雨特征进行了分析。结果表明:(1)芦山县暴雨呈纬向地带性分布,南多北少,集中出现在7月和8月,年际变化总体上呈现不显著上升趋势;(2)芦山县暴雨由单峰型暴雨主导,雨峰出现... 详细信息

基于2013-2022年芦山站、太平站、保卫站降水整编资料,对芦山县暴雨特征进行了分析。结果表明:(1)芦山县暴雨呈纬向地带性分布,南多北少,集中出现在7月和8月,年际变化总体上呈现不显著上升趋势;(2)芦山县暴雨由单峰型暴雨主导,雨峰出现时间基本都在降雨过程的前中期,雨峰占比与降雨历时有明显负相关关系;(3)芦山县年暴雨量波动变化明显,在时间序列上呈现不显著上升趋势,芦山站单次暴雨量在时间序列上呈现显著上升趋势,突变分析结果表明发生显著变化时间为2018年8月上旬。

关键词：暴雨特征趋势检验芦山县

Spectroscopic Diagnostics of Rotational Temperature in the Pulsed Atmospheric Air Plasma

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高电压技术 2013年第10期39卷 2568-2572页

作者： DONG Pan LI Jie LI Xi XIE Yutong LONG jidong zhang Linwen Key Laboratory of Pulsed Power Institute of Fluid Physics China Academy of Engineering Physics Mianyang 621900 China

Dielectric barrier discharge(DBD) attracts lots of attentions for its great application promises,and the rotational temperature is one of its mostly important *** order to measure the rotational temperature of a pulsed DBD in atmospheric air,the temperature is studied by using optical emission spectroscopy(OES).The discharge is excited by a high voltage pulse with 124 ns rise time and 230 ns full width at half maximum(FWHM) at a repetition rate of a few hundred *** rotational temperatures are studied using different voltages,different repetition rates of the pulse power supply,and different gaps between dielectrics: They are in the range from 390 K to 500 K during the whole *** the gap between dielectrics increases,the rotational temperature initially decreases and then *** rotational temperature changes complexly when the pulse repetition rate *** the voltage increases,the rotational temperature always decreases,which is not *** results allow one to predict the rotational temperature at different supply power parameters and electrode configurations,which is useful for the DBD's industrial application.

关键词：转动温度高压脉冲空气等离子光谱诊断大气介质阻挡放电光学发射光谱脉冲重复频率

LogGPO:An accurate communication model for performance prediction of MPI programs

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Science in China(Series F) 2009年第10期52卷 1785-1791页

作者： CHEN WenGuang ZHAI jidong zhang Jin ZHENG WeiMin Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and Technology TsinghuaUniversity Beijing 100084 China

Message passing interface （MPI） is the de facto standard in writing parallel scientific applications on distributed memory systems. Performance prediction of MPI programs on current or future parallel systems can help to find system bottleneck or optimize programs. To effectively analyze and predict performance of a large and complex MPI program, an efficient and accurate communication model is highly needed. A series of communication models have been proposed, such as the LogP model family, which assume that the sending overhead, message transmission, and receiving overhead of a communication is not overlapped and there is a maximum overlap degree between computation and communication. However, this assumption does not always hold for MPI programs because either sending or receiving overhead introduced by MPI implementations can decrease potential overlap for large messages. In this paper, we present a new communication model, named LogGPO, which captures the potential overlap between computation with communication of MPI programs. We design and implement a trace-driven simulator to verify the LogGPO model by predicting performance of point-to-point communication and two real applications CG and Sweep3D. The average prediction errors of LogGPO model are 2.4% and 2.0% for these two applications respectively, while the average prediction errors of LogGP model are 38.3% and 9.1% respectively.

关键词： performance prediction communication model LogP LogGPO MPI

In situ Characterization of Phase Transition of Amorphous Poly(9,9-di-n-octyl-2,7-fluorene)Thin Film During Thermal Annealing

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Chemical Research in Chinese Universities 2019年第1期35卷 157-162页

作者： MENG Shengfei WANG Pengyue CHEN Liuran GAO Guanghui zhang jidong School of Chemical Engineering and Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012P.R.China State Key Lab of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Aeademy of SciencesChangchun 130022P.R.China

Amorphous poly(9,9-di-n-octyl-2,7-fluorene)(PFO)thin films were characterized in situ via thermal an- nealing based on grazing incidence X-ray diffraction(GIXRD)profiles,UV-visible absorption spectrophotometry,and Fourier transform infrared spectroscopy(FTIR).The results of GIXRD indicated that the amorphous phase transformed into a crystalline phase when the annealing temperature was higher than 80 ℃.Different outcomes were elicited for the intensities and d-spacings of the diffraction peaks below and above 80 ℃,which were attributed to the formation of the κ-*** mechanism of phase transition was revealed by in situ UV-visible absorption and FTIR spectra,whereby the rearrangement of the side chains was dominant and the movement of the main chains was minimal,even when the annealing temperature was lower than 80 ℃.In contrast,the rearrangement of the main chains was dominant when the temperature was higher than 80 ℃.

关键词： Polyfluorene Phase transition Thermal annealing Liquid crystalline κ-phase

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库仑滴定法测定烟草中总氮的含量

理化检验（化学分册） 2024年第5期60卷 467-471页

作者：张继东刘伟王珺蔡保国刘丹丹杨栋河南中烟工业有限责任公司安阳卷烟厂安阳455004 南华大学土木工程学院衡阳421001

取已处理过的烟草样品0.20 g,用0.2 g硫酸铜、0.3 g硫酸钾和6 mL硫酸于170℃消解1 h后,再升温至370℃继续消解2 h。待消解液冷却至室温后,滴加8 mol·L^(-1)氢氧化钾溶液,调节消解液pH至4.0~5.0,用水定容至50 mL。以铂电极-铂丝对电极... 详细信息

取已处理过的烟草样品0.20 g,用0.2 g硫酸铜、0.3 g硫酸钾和6 mL硫酸于170℃消解1 h后,再升温至370℃继续消解2 h。待消解液冷却至室温后,滴加8 mol·L^(-1)氢氧化钾溶液,调节消解液pH至4.0~5.0,用水定容至50 mL。以铂电极-铂丝对电极作电解电极对,铂电极作指示电极对,四硼酸钠-溴化钾溶液(溴化钾浓度为1.2 mol·L^(-1),pH 8.6~8.9)作电解质溶液,在适当的电解电流下,滴定剂BrO~-定量滴定预处理后样品溶液中NH_4~+,通过到达滴定终点的电解时间,根据法拉第定律测定总氮的含量。结果表明,按标准加入法进行回收试验,回收率为95.1%~109%,测定值的相对标准偏差(n=5)均小于2.0%。方法用于实际样品的分析,与YC/T 161-2002中连续流动法测定结果相比较,结果无显著性差异,与杜马斯燃烧法的测定结果相近,但本方法无需提前准备大量试剂,且操作简便,耗时短。

关键词：库仑滴定法烟草总氮消解溴化钾