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镁合金腐蚀与防护综合实验教学设计

实验室研究与探索 2024年第1期43卷 143-146页

作者：许婷熠佘加赵燕飞王金星汤爱涛吴刚重庆大学材料科学与工程学院重庆400044

设计了镁合金腐蚀与防护综合实验中镁合金防护、腐蚀性能评定两大模块,实验方案从镁合金成分设计、表面处理工艺两方面开展,通过析氢测量、浸泡失重、电化学实验表征镁合金的腐蚀速度,进而探究实验方案的可行性。教学模式以学生为主体,... 详细信息

设计了镁合金腐蚀与防护综合实验中镁合金防护、腐蚀性能评定两大模块,实验方案从镁合金成分设计、表面处理工艺两方面开展,通过析氢测量、浸泡失重、电化学实验表征镁合金的腐蚀速度,进而探究实验方案的可行性。教学模式以学生为主体,采用线上线下教学,将科学研究的方法引入实验教学,实验内容具有延续性,实现了科教融合。

关键词：腐蚀与防护镁合金实验教学

Modeling the transmission dynamics of COVID-19 epidemic: a systematic review

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The Journal of Biomedical Research 2020年第6期34卷 422-430,I0001-I0013页

作者： jinxing Guan Yongyue Wei Yang zhao Feng Chen Department of Epidemiology and Biostatistics School of Public HealthCenter for Global HealthNanjing Medical UniversityNanjingJiangsu 211166China.

The outbreak and rapid spread of COVID-19 has become a public health emergency of international concern.A number of studies have used modeling techniques and developed dynamic models to estimate the epidemiological parameters,explore and project the trends of the COVID-19,and assess the effects of intervention or control *** identified 63 studies and summarized the three aspects of these studies:epidemiological parameters estimation,trend prediction,and control measure *** the discrepancy between the predictions and the actuals,the dynamic model has made great contributions in the above three *** most important role of dynamic models is exploring possibilities rather than making strong predictions about longer-term disease dynamics.

关键词： coronavirus COVID-19 epidemiology modeling transmission dynamic model SEIR model SIR model

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行李箱外板上段侧整形起皱问题优化

模具工业 2024年第5期50卷 31-34页

作者：赵子海张鹏慎金星王锐比亚迪汽车工业有限公司技术中心广东深圳518118

汽车行李箱外板上段的下部与贯穿灯搭接处侧整形时起皱,传统冲压工艺中该处采用5道工序成形,介绍的新工艺采用4道工序完成该处成形,第2道工序对该处进行侧修边,首次侧整形采用阻止材料流入的台阶,避免首次侧整形时起皱;二次侧翻边时通... 详细信息

汽车行李箱外板上段的下部与贯穿灯搭接处侧整形时起皱,传统冲压工艺中该处采用5道工序成形,介绍的新工艺采用4道工序完成该处成形,第2道工序对该处进行侧修边,首次侧整形采用阻止材料流入的台阶,避免首次侧整形时起皱;二次侧翻边时通过增加吸皱造型及取消缺口,以保证最终制件的成形质量。

关键词：行李箱外板侧整形起皱阻料台阶

On the snap-through time of a nanoscale elastic strip

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Acta Mechanica Sinica 2022年第4期38卷 21-28,I0001页

作者： Ziyu zhao jinxing Liu Ai Kah Soh Chun Tang Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013China School of Engineering Monash University MalaysiaSelangor Darul Ehsan 47500Malaysia

We have examined the elastic snap-through behaviors of single crystal copper strips numerically and theoretically to investigate factors that influence the characteristic snap-through time *** strip is simply supported on both ends,and the snap-through is launched by suddenly removing the concentrated forces that have already been statically applied to produce an initial bending *** the one hand,the process is implemented in the molecular dynamics(MD)simulator *** the other hand,a theoretical formulation is provided with the consideration of surface *** surface tension is found to increase the snap-through *** results show that the snap-through behavior is further closely related to the magnitude of the initially stored deformation and the strip ***,snap-through times provided by the above numerical and theoretical analyses are on the same order of *** is an interesting agreement,especially considering that the huge gap of time scales between MD simulations and experiments has been a well-known fundamental *** believe that the present study about spontaneous processes such as snap-through has cast some light on the fbndamental issue that deformation in MD simulations generally happens much faster than in physical experiments.

关键词： Snap-through Characteristic time Continuum modeling Molecular dynamics simulation Surface stress

基于丝网印刷电极和重氮官能化的赭曲霉素A电化学免疫传感检测方法的建立与应用

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食品研究与开发 2024年第17期45卷 149-158页

作者：宋心怡王鑫赵晓磊何金兴齐鲁工业大学(山东省科学院) 山东济南250000

该文将赭曲霉素A(ochratoxin A,OTA)抗体和重氮盐接枝在电极表面,构建一种用于OTA快速检测的电化学免疫传感器。通过电沉积的方法将重氮盐修饰于丝网印刷碳电极(screen-printed carbon electrodes,SPCE),接枝的重氮膜作为底层,使羧基官... 详细信息

该文将赭曲霉素A(ochratoxin A,OTA)抗体和重氮盐接枝在电极表面,构建一种用于OTA快速检测的电化学免疫传感器。通过电沉积的方法将重氮盐修饰于丝网印刷碳电极(screen-printed carbon electrodes,SPCE),接枝的重氮膜作为底层,使羧基官能团暴露在电极表面。然后使用碳二亚胺对羧基进行活化,用交联的方式使抗体和羧基进行酰胺键合从而实现抗体的固定化。利用循环伏安(cyclic voltammetry,CV)法和电化学阻抗谱(electrochemical impedance spectroscopy,EIS)表征电化学免疫传感器的特性。结果表明,在最佳工作条件下,所开发的电化学免疫传感器的线性检测范围为20~200 ng/mL(R2=0.9970),检测限为0.5 ng/mL,在检测加标样品中OTA方面表现出优异的电化学性能,适用于食品中OTA的检测。此外,在干扰物存在的情况下,该传感器对OTA具有高度选择性,且贮存14 d稳定性仍较好。该电化学免疫传感器易于构建、灵敏、快速且稳定,对实际样品中OTA的检测限低,分析时间短和成本低。

关键词：赭曲霉素A 电化学免疫传感器重氮化丝网印刷碳电极快速检测

基于Fluent的环境温度和斜井角度对隧道通风效果的影响研究

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工业安全与环保 2024年第1期50卷 49-53页

作者：赵振新鲍旺旺李晓宇赵亮李晋兴山西静兴高速公路有限公司山西吕梁033500 西安建筑科技大学资源工程学院陕西西安710055 中铁六局集团电务工程有限公司山西太原030013 兵器工业卫生研究所陕西西安710061

针对隧道斜井的自然通风问题,以大万山隧道为依托工程,利用CFD数值模拟软件Fluent对斜井型隧道进行模拟,分析不同环境温度和隧道斜井角度对隧道通风效果的影响。结果表明,环境温度和斜井角度都影响隧道的通风效果。当环境温度低于隧道... 详细信息

针对隧道斜井的自然通风问题,以大万山隧道为依托工程,利用CFD数值模拟软件Fluent对斜井型隧道进行模拟,分析不同环境温度和隧道斜井角度对隧道通风效果的影响。结果表明,环境温度和斜井角度都影响隧道的通风效果。当环境温度低于隧道壁温时,斜井处于排风状态;环境温度高于隧道壁温时,斜井处于送风状态,二者温差越大,隧道和斜井内的风速越大;当环境温度一致时,斜井角度成为影响隧道通风效果的主要因素,斜井角度为90°时隧道通风效果最佳,随着斜井角度的减小,隧道通风效果逐渐变差。

关键词：公路隧道斜井角度环境温度 Fluent 通风效果

Ce-Fe-Mn ternary mixed-oxide catalysts for catalytic decomposition of ozone at ambient temperatures

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Journal of Rare Earths 2020年第2期38卷 175-181页

作者： Xiao Chen Zhenglong zhao Shuo Liu jinxing Huang Jing Xie Ying Zhou Zhiyan Pan Hanfeng Lu Institute of Environmental Chemicals and Resources College of EnvironmentZhejiang University of TechnologyHangzhou 310014China Innovation Team of Air Pollution Control Institute of Catalytic Reaction EngineeringCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China Hangzhou Runxing Technology Co. Ltd.Hangzhou 310014China

Ce-modified Mn-Fe mixed-oxide catalysts were prepared by a citric acid sol-gel method and characterized by X-ray diffraction,Raman,N2 adsorption-desorption,infrared spectra H2 temperature-programmed reduction and thermogravimetric *** catalytic properties were investigated in ozone(O3)decomposition *** show that the small amount of rare earth metal Ce added during Mn-Fe(FM) mixed-oxide synthesis greatly improves the catalytic performance in O3 *** the prepared *** C0.04(FM)0.96 mixed-oxide catalyst exhibits the highest catalytic activity and *** O3 conversion over C0.04(FM)0.96 is 98% after 24 h reaction at 25℃ under dry condition,and that over FM decreases to 90% after 16 h *** 0℃,the O3 conversion over C0.04(FM)0.96 is 95% after 7 h reaction under dry *** that over FM slows down to 70%.Under humid condition(RH 65%),the O3 conversion over C0.04(FM)0.96 is 63% after 6.5 h reaction at 25℃.while that over FM decreases to 55%.When Ce is doped into Mn-Fe mixed oxides,the small amount of Ce enters the crystal lattice of *** partial Fe is separated to form *** changes cause lattice distortion and increase defects and enable the as-synthesized Ce-Fe-Mn ternary mixed-oxide catalysts to acquire additional oxygen vacancies and increase their specific surface area,thereby increasing the number of reaction sites and enhancing the catalytic performance of the catalysts for O3 decomposition.

关键词： Rare earths modified Ce-Fe-Mn mixed oxide Oxygen vacancy Ozone Catalytic decomposition

Radio Channel Measurements and Analysis at 2.4/5GHz in Subway Tunnels

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China Communications 2015年第1期12卷 36-45页

作者： LI jinxing zhao Youping ZHANG Jing JIANG Rui TAO Cheng TAN Zhenhui Institute of Broadband Wireless Mobile Communications School of Electronics and Information EngineeringBeijing Jiaotong University

There is an increasing demand on wireless communications in subway tunnels to provide video surveillance and sensory data for security,maintenance and train control,and to offer various communication or entertainment services(e.g.,Internet,etc.) to passengers as *** wireless channel in tunnels is quite unique due to the confined space and the waveguide ***,modeling the radio channel characteristics in tunnels is critically important for communication systems design or *** paper investigates the key radio channel characteristics of a subway tunnel at 2.4 GHz and 5 GHz,such as the path loss,root mean square(RMS) delay spread,channel stationarity,Doppler shift,and channel *** field measurements show that channel characteristics in tunnels are highly location-dependent and there exist abundant components in Doppler shift *** the straight section of the subway tunnel,the measured path loss exponents are close to1.6,lower than that in free space.

关键词： broadband mobile communication channel measurement channel characteriza-tion subway tunnel

Application of Activated Alumina Powders in Corundum Castables

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China's Refractories 2019年第2期28卷 12-17页

作者： LI Youqi DING jinxing CUI Qingyang zhao Jizeng Beijing Lier High-Temperature Materials Co. Ltd.Beijing 102211China Luoyang Lier Functional Materials Co. Ltd.Luoyang 471023China

There are many brands of activated alumina powders in the market and the products from different manufacturers exist subtle differences. In this work, four brands of activated alumina powder which are the mainstream products in China with the same marked particle size of 2-3 μm were added to corundum castables to investigate the effect of different activated alumina powder on properties of corundum castables. It is found that the multi-peak distribution, round-shape particle,low impurities content of alumina powder are of great benefit to the improvement of the overall performance of *** CA6 frame structure formed in castables matrix is conductive to improving the thermal shock resistance and high temperature strength of castables. One kind of domestic alumina micropowder studied in this work has good application value and prospect in corundum castables because of the excellent comprehensive performance.

关键词： activated alumina powder corundum castables calcium hex-aluminate