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Nitrogen–sulfur co-doped porous carbon derived from asphalt as efficient catalyst for oxygen reduction

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Rare Metals 2024年第1期43卷 380-388页

作者： jing-sheng Ma Ming-Zai Wu Ling Chen Li-Xing Zhang Ying Xiong Key Laboratory of Structure and Functional Regulation of Hybrid Materials Ministry of EducationInstitute of EnergyHefei Comprehensive National Science CenterAnhui UniversityHefei 230601China

As an environment-friendly and low-cost petrochemical by-product, asphalt has great potential in the preparation of metal-free oxygen reduction electrocatalysts with excellent performance and outstanding stability. In this paper, we converted asphalt into porous carbon nanosheets by a simple activation method, using potassium citrate as the swelling agent.

关键词： stability porous catalyst

Unique polysulfide reaction on VO2 for restraining shuttle effect in soft-packaged Li-S pouch cells

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Rare Metals 2024年第6期43卷 2842-2850页

作者： Ruo-Xuan Yang Qing-Chun Zhang jing-sheng Cai Xuan Cao Qin Yang Ying-Ze Song Wei Zhang State Key Laboratory of Environment-Friendly Energy Materials Tianfu Institute of Research and InnovationSchool of Materials and ChemistrySouthwest University of Science and Technology School of Materials Engineering Changshu Institute of Technology Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences

The shuttle phenomenon and retarded conversion kinetics of lithium poly sulfides （LiPSs） are relatively severe in lithium-sulfur （Li-S） pouch cells.Owing to their redox potential in the sulfur working window,VO2na... 详细信息

关键词： Vanadium dioxide

Plasma metabolites and risk of myocardial infarction:a bidirectional Mendelian randomization study

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Journal of Geriatric Cardiology 2024年第2期21卷 219-231页

作者： Dong-Hua LI Qiang WU jing-sheng LAN Shuo CHEN You-Yi HUANG Lan-Jin WU Zhi-Qing QIN Ying HUANG Wan-Zhong HUANG Ting ZENG Xin HAO Hua-Bin SU Qiang SU Department of Cardiovascular Medicine Minzu Hospital of Guangxi Zhuang Autonomous RegionGuangxiChina Senior Department of Cardiology the Sixth Medical CenterChinese PLA General HospitalBeijingChina Library of Graduate School Chinese PLA General HospitalBeijingChina Department of Cardiology Jiangbin Hospital of Guangxi Zhuang Autonomous RegionGuangxiChina Health Management Institute the Second Medical CenterChinese PLA General HospitalBeijingChina

BACKGROUND Myocardial infarction(MI)is a critical cardiovascular event with multifaceted etiology,involving several genetic and environmental factors.It is essential to understand the function of plasma metabolites in the development of MI and unravel its complex pathogenesis.METHODS This study employed a bidirectional Mendelian randomization(MR)approach to investigate the causal relationships between plasma metabolites and MI risk.We used genetic instruments as proxies for plasma metabolites and MI and conducted MR analyses in both directions to assess the impact of metabolites on MI risk and vice versa.In addition,the large-scale genome-wide association studies datasets was used to identify genetic variants associated with plasma metabolite(1400 metabolites)and MI(20,917 individuals with MI and 440,906 individuals without MI)susceptibility.Inverse variance weighted was the primary method for estimating causal effects.MR estimates are expressed as beta coefficients or odds ratio(OR)with 95%CI.RESULTS We identified 14 plasma metabolites associated with the occurrence of MI(P<0.05),among which 8 plasma metabolites[propionylglycine levels(OR=0.922,95%CI:0.881–0.965,P<0.001),gamma-glutamylglycine levels(OR=0.903,95%CI:0.861–0.948,P<0.001),hexadecanedioate(C16-DC)levels(OR=0.941,95%CI:0.911–0.973,P<0.001),pentose acid levels(OR=0.923,95%CI:0.877–0.972,P=0.002),X-24546 levels(OR=0.936,95%CI:0.902–0.971,P<0.001),glycine levels(OR=0.936,95%CI:0.909–0.964,P<0.001),glycine to serine ratio(OR=0.930,95%CI:0.888–0.974,P=0.002),and mannose to trans-4-hydroxyproline ratio(OR=0.912,95%CI:0.869–0.958,P<0.001)]were correlated with a decreased risk of MI,whereas the remaining 6 plasma metabolites[1-palmitoyl-2-arachidonoyl-GPE(16:0/20:4)levels(OR=1.051,95%CI:1.018–1.084,P=0.002),behenoyl dihydrosphingomyelin(d18:0/22:0)levels(OR=1.076,95%CI:1.027–1.128,P=0.002),1-stearoyl-2-docosahexaenoyl-GPE(18:0/22:6)levels(OR=1.067,95%CI:1.027–1.109,P=0.001),alpha-ketobutyrate levels(OR=1.108,95%CI:1.041–1.180,P=0.001),5-acetylamino-6-formylam

关键词： infarction alterations diagnosis

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20世纪中国女性雕塑家的觉醒与表达

美术 2024年第4期 97-105页

作者：盛静北京工业大学艺术设计学院

中国女性雕塑家的产生和现代意义上雕塑学科的建立几乎是同步的。本文以生于20世纪初的中国女性雕塑家为研究对象,以其艺术作品为线索探寻影响现代中国第一代女性雕塑家群体创作观念的因素。这些女性雕塑家艺术创作的变化和中国社会主... 详细信息

中国女性雕塑家的产生和现代意义上雕塑学科的建立几乎是同步的。本文以生于20世纪初的中国女性雕塑家为研究对象,以其艺术作品为线索探寻影响现代中国第一代女性雕塑家群体创作观念的因素。这些女性雕塑家艺术创作的变化和中国社会主流意识的关系紧密,受西方女性主义和消费主义的影响较小,她们的创作旺盛期贯穿新民主主义革命到改革开放等多个历史阶段,其作品反映了中国社会变迁对艺术创作产生的主导性作用。

关键词：中国现代雕塑女性雕塑家女性主义个体意识

配合间隙对直线共轭内啮合齿轮泵流场特性的影响

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农业机械学报 2024年第2期55卷 442-449页

作者：陈鼎张杨叶绍干盛精厦门理工学院机械与汽车工程学院厦门361024 厦门大学萨本栋微米纳米科学技术研究院厦门361021

直线共轭内啮合齿轮泵是液压系统中的关键组件,因其高效的压力输送特性而广泛应用于工程领域。本文采用计算流体动力学模拟方法对直线共轭内啮合齿轮泵进行研究,分析轴向间隙和径向间隙对齿轮泵泄漏和流场的影响。研究结果表明:配合间... 详细信息

直线共轭内啮合齿轮泵是液压系统中的关键组件,因其高效的压力输送特性而广泛应用于工程领域。本文采用计算流体动力学模拟方法对直线共轭内啮合齿轮泵进行研究,分析轴向间隙和径向间隙对齿轮泵泄漏和流场的影响。研究结果表明:配合间隙的变化对齿轮泵的流场特性产生广泛影响,轴向间隙是引发泄漏的主要因素,约占总泄漏量的80%;当轴向间隙由0.03 mm增加到0.07 mm后,输出流量减少20.81%,平均压力下降33.15%,空化产生的气体体积分数增加0.021;而设置相同径向间隙后,输出流量仅下降0.69%,平均压力下降2.76%,空化产生的气体体积分数增加0.005。此外,导致泵内流速变化的主要配合间隙是轴向间隙,适当减小轴向间隙可提升泵内的流体速度,从而提升泵的整体效率。

关键词：直线共轭内啮合齿轮泵泄漏流场特性配合间隙

Green manure rotation and application increase rice yield and soil carbon in the Yangtze River valley of China

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Pedosphere 2023年第4期33卷 589-599页

作者： Qian YUE Jianfei SUN Jonathan HILLIER jing sheng Zhi GUO Puping ZHU Kun CHENG Genxing PAN Yunpeng LI Xin WANG Key Laboratory for Crop and Animal Integrated Farming of Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Environment Jiangsu Academy of Agricultural SciencesNanjing 210014(China) Nanjing Institute of Environmental Sciences Ministry of Ecology and EnvironmentNanjing 210042(China) Global Academy of Agriculture and Food Security The Royal(Dick)School of Veterinary Studies and The Roslin InstituteThe University of EdinburghEaster Bush CampusMidlothian EH259RG(UK) Institute of Resource Ecosystem and Environment of AgricultureNanjing Agricultural UniversityNanjing 210095(China)

The addition of organic matter via green manure rotation with rice is considered a smart agricultural practice to maintain soil productivity and support environmental sustainability.However,few studies have quantitatively assessed the impact of green manure rotation and application on the interactions between agronomic management practice,soil fertility,and crop production.In this study,800 pairs of data from 108 studies conducted in the agricultural region of the Yangtze River,China were assessed,and random forest(RF)modeling was performed to evaluate the effect of green manure rotation and application on rice yield and soil properties.Compared to a winter fallow system,rotation and application of green manure significantly increased rice yield and soil organic carbon(SOC)by 8.1%and 8.4%,respectively.According to the RF models,rice type,green manure application rate and duration,mineral and organic nitrogen application rates,and initial SOC content and soil pH were identified as the main drivers for rice yield and SOC changes.Marginal benefit analysis revealed that green manure application rates for early rice in double cropping system and the rice in single cropping system were approximately 20 and 26 t ha-1(fresh weight),respectively.Further,the optimum green manure application rate was approximately 25 t ha-1(fresh weight)for carbon sequestration.However,it should be noted that green manure application to soils with high SOC level might result in the soils becoming a net carbon source.Our study contributed scientific and quantitative indicators for achieving the greatest benefits in rice yield and increasing SOC upon application of green manure.

关键词： carbon sequestration crop production random forest model soil fertility soil organic carbon

波前编码红外成像系统的温度梯度适应能力探究

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天津大学学报（自然科学与工程技术版） 2024年第5期57卷 521-529页

作者：盛婧蔡怀宇汪毅陈晓冬天津大学精密仪器与光电子工程学院天津300072

利用波前编码技术为红外光学系统进行无热化设计可提高其在不同均匀工作温度下的适应能力,但针对温度突变、成像系统内温度分布不均情况,波前编码技术是否能正常进行成像及其适用的温度范围还有待进一步研究.为简化分析流程,采用温度梯... 详细信息

利用波前编码技术为红外光学系统进行无热化设计可提高其在不同均匀工作温度下的适应能力,但针对温度突变、成像系统内温度分布不均情况,波前编码技术是否能正常进行成像及其适用的温度范围还有待进一步研究.为简化分析流程,采用温度梯度模型来仿真非稳态下的温度变化.利用温度梯度模型来定性分析光学系统在轴向、径向温度梯度为系统引入的附加像差.计算两个方向下的光程差变化来比较两种温度梯度环境下系统的成像性能差异.在此基础上,为非稳态温度环境下红外光学系统的设计建立了结合光/机/热分析的无热化设计流程,通过ZEMAX设计了一套最大轴向尺寸为85 mm、最大径向尺寸为25 mm的红外光学系统,通过SolidWorks加载轴向和径向的热形变,探究所设计的系统能够适用的温度梯度范围.结果表明,结合光/机/热分析的无热化设计流程可以有效表明系统在非稳态温度下的成像情况.对上述采用三次相位板进行无热化设计的红外光学系统,在非稳态温度下可以适应±10℃的轴向温差范围,但是仅可以适应±1℃的径向温差范围.因此在进行红外波前编码光学系统的无热化设计时,需要对径向方向进行重点优化.

关键词：波前编码技术红外光学成像系统温度梯度三次相位板

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基于双螺旋相位板的单目三维编码成像

光学学报 2024年第9期44卷 77-92页

作者：张越蔡怀宇盛婧汪毅陈晓冬天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室天津300072

提出一种能够同时获得场景深度信息并实现景深拓展的成像方法。通过在相机的光瞳处引入双螺旋相位调制,将深度信息编码在图像中,使用端到端的深度学习技术对成像过程进行反演,最终得到景深拓展的图像和深度图。分析了相位板参数和物距... 详细信息

提出一种能够同时获得场景深度信息并实现景深拓展的成像方法。通过在相机的光瞳处引入双螺旋相位调制,将深度信息编码在图像中,使用端到端的深度学习技术对成像过程进行反演,最终得到景深拓展的图像和深度图。分析了相位板参数和物距对成像性能的影响,讨论了在给定的深度范围内合理选择相位板参数的方法。在NYU Depth V2数据集的深度范围内进行了仿真,深度估计相对误差最低可达8.3%,景深拓展后图像的峰值信噪比(PSNR)和结构相似度(SSIM)最高分别可达35.254 dB和0.960,所提方法与传统光学系统相比景深可拓展数十倍以上,并且结果证明了缩小探测范围和增大物距可提升平均深度估计精度。针对闸机人脸识别等潜在的应用场景,以1.1~1.32 m为探测范围搭建了实物系统,在真实场景中深度估计的相对误差为2.2%,所提方法相比传统光学系统景深拓展约10倍。本文方法仅需在传统成像系统中加入一块相位板即可同时实现场景的深度估计和景深拓展功能,在低成本三维成像和检测领域具有一定的应用潜力。

关键词：成像系统计算成像单目深度估计景深拓展双螺旋相位板点扩散函数

Shear-induced Crystallization in Phase-separated Blends of Isotactic Polypropylene with Ethylene-Propylene-Diene Terpolymer

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Chinese Journal of Polymer Science 2015年第11期33卷 1538-1549页

作者：马桂秋 Da Li jing sheng School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

The compatibility between isotactic polypropylene（iPP） and ethylene-propylene-diene terpolymer（EPDM） in the blends was studied. SAXS analysis indicates that iPP and EPDM phases in the binary blend are incompatible. Isothermal crystallization behaviors of iPP in phase-separated iPP/EPDM were studied by in situ POM equipped with a Linkam shear hot stage. It was found that typical spherulites of iPP were formed both in neat iPP and in iPP/EPDM blends. The radial growth rate（d R/dt） of spherulites of iPP in the blend was not influenced by EPDM phases. Further investigations on isothermal crystallization of iPP in iPP/EPDM after shear with a fixed shear time showed that the crystallization rate of iPP in the blends increased with increasing shear rates, whereas, the crystallization rate was much lower than that of neat iPP. WAXD results showed that β-crystal iPP was formed in neat iPP as well as in iPP/EPDM blends after shearing and the percentage of β-crystal bore a relationship to the applied shear rate. The presence of EPDM resulted in lower percentage of β-crystal in the blends than that in neat iPP under the same constant shear conditions. SAXS experiments revealed that shear flow could induce formation of oriented lamellae in iPP and iPP in the blends, and the presence of EPDM led to a reduced fraction of oriented lamellae.

关键词： Shear-induced crystallization Polypropylene EPDM Blends β-Crystal