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Theoretical study of the elastic properties of titanium nitride

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Acta Metallurgica Sinica(English Letters) 2009年第2期22卷 146-152页

作者： Dong chen Jingdong chen Yinglu ZHAO Benhai YU Chunlei WANG Deheng SHI College of Physics and Electronic Engineering Xinyang Normal University Xinyang 464000 China College of Physics and Electronic Engineering Ludong University Yantai 264025 China

The equilibrium lattice parameter, relative volume V/V0, elastic constants Cij, and bulk modulus of titanium nitride are successfully obtained using the ab initio planewave pseudopotential （PW-PP） method within the framework of density functional theory. The quasi-harmonic Debye model, using a set of total energy vs molar volume obtained with the PW-PP method, is applied to the study of the elastic properties and vibrational effects. We analyze the relationship between the bulk modulus and temperature up to 2000 K and obtain the relationship between bulk modulus B and pressure at different temperatures. It is found that the bulk modulus B increases monotonously with increasing pressure and decreases with increasing temperature. Moreover, the Debye temperature is determined from the non-equilibrium Gibbs functions.

关键词： Elastic constants Debye temperature Ab initio calculations Titanium nitride

Metathesis of 1-butene and 2-butene to propene over Re_2O_7 supported on macro-mesoporous γ-alumina prepared via a dual template method

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Journal of Natural Gas Chemistry 2012年第2期21卷 105-108页

作者： Lei Sang Sheng-Li chen Guimei Yuan Min Zheng Ju You Aicheng chen Rui Li Lanjing chen State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumBeijing 102249China

Macro-mesoporous γ-alumina support（MMA） was prepared by a sol-gel route in aqueous medium using pseudo-boehmite as aluminum source and polystyrene microspheres and Pluronic P123 as hard and soft dual templates,*** had a BET specific surface area of about 259 m2 g-1,total pore volume of about 1.61 cm3 g-1,macropore diameter of about 102 nm,and mesopore diameter of about 14 ***2O7/MMA and conventional Re2O7/Al2O3 were prepared by a incipient-wetness impregnation method,and their catalytic performances in the metathesis of 1-butene and 2-butene were tested in a fixed-bed tubular *** result showed that Re2O7/MMA possessed higher activity and far longer working life-span than conventional Re2O7/Al2O3.

关键词： butene metathesis propene rhenium oxide polystyrene microspheres macro-mesoporous alumina

Vehicle Dynamic State Estimation： State of the Art Schemes and Perspectives

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IEEE/CAA Journal of Automatica Sinica 2018年第2期5卷 418-431页

作者： Hongyan Guo Dongpu Cao Hong chen chen Lv Huaji Wang Siqi Yang State Key Laboratory of Automotive Simulation and Control and the Department of Control Science and Engineering Jilin University (Campus Nanling) Changchun 130025 China the Mechanical and Mechatronics Engineering Department at the University of Waterloo N2L 3GI Canada Department of Automotive Engineering Cranfield University Bedfordshire MK43 0AL UK IEEE

Next-generation vehicle control and future autonomous driving require further advances in vehicle dynamic state estimation. This article provides a concise review, along with the perspectives, of the recent developments in the estimation of vehicle dynamic states. The definitions used in vehicle dynamic state estimation are first introduced, and alternative estimation structures are presented. Then, the sensor configuration schemes used to estimate vehicle velocity, sideslip angle, yaw rate and roll angle are presented. The vehicle models used for vehicle dynamic state estimation are further summarized, and representative estimation approaches are discussed. Future concerns and perspectives for vehicle dynamic state estimation are also discussed.

关键词： Index Terms-Estimation structure extended Kalman filter sensor configuration sideslip angle estimation vehicle dynamicstate estimation vehicle dynamics model.

Hierarchical porous onion-shaped LiMn204 as cathode material for lithium ion batteries

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Nano Research 2018年第8期11卷 4038-4048页

作者： Zihe Li Xiangming Feng Liwei Mi Jinyun Zheng Xiaoyang chen Weihua chen College of Chemistry and Molecular Engineering Zhengzhou University Zhengxhou 45000 I China Center for Advanced Materials Research Zhongyuan University of Technology Zhengzhou 450007 China National Engineering and Research Center for Adv. Polymer Processing Technology Zhengzhou University Zhengzhou 450001 China

Spinel niMn2O4 is a widely utilized cathode material for Li-ion batteries. However, its applications are limited by its poor energy density and power density. Herein, a novel hierarchical porous onion-like LiMn204 （LMO） was prepared to shorten the Li diffusion pathway with the presence of uniform pores and nanosized primary particles. The growth mechanism of the porous onion-like LiMn204 was analyzed to control the morphology and the crystal structure so that it forms a polyhedral crystal structure with reduced Mn dissolution. In addition, graphene was added to the cathode （LiMn2Odgraphene） to enhance the electronic conductivity. The synthesized LiMn2O4/graphene exhibited an ultrahigh-rate performance of 110.4 rnAh.g-1 at 50 C and an outstanding energy density at a high power density maintaining 379.4 ***-1 at 25,293 ***-L Besides, it shows durable stability, with only 0.02% decrease in the capacity per cycle at 10 C. Furthermore, the （LiMn2O4/graphene）/graphite full-cell exhibited a high discharge capacity. This work provides a promising method for the preparation of outstanding, integrated cathodes for potential applications in lithium ion batteries.

关键词： KEYWORDSLiMn2O4 hierarchical porous shape cathode rate performance Li-ion batteries

基于蓝牙Mesh的智能车位检测控制系统设计与实现

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现代信息科技 2025年第1期9卷 171-176页

作者：张业伟钟可馨周瑜陈晨高士虎安徽三联学院工学部安徽合肥230601

为解决老旧停车场更新停车管理系统成本高、维修困难、能耗大等问题,设计了基于蓝牙Mesh本地组网和云端服务器的智能车位检测系统。该系统具有低能耗、维修简便、安装成本低、操作简单等优点。选择了功耗低、价格实惠的超声波监测技术,... 详细信息

为解决老旧停车场更新停车管理系统成本高、维修困难、能耗大等问题,设计了基于蓝牙Mesh本地组网和云端服务器的智能车位检测系统。该系统具有低能耗、维修简便、安装成本低、操作简单等优点。选择了功耗低、价格实惠的超声波监测技术,并详细设计了硬件和软件方案,实现了精确的车位检测和数据传输功能。经过软硬件测试,结果显示该系统运行稳定可靠,通信性能优良,维护成本低。这一设计为未来智能停车场管理提供了创新的解决方案。

关键词： STM32 Mesh组网智慧停车

KIF20B作为肺腺癌浸润相关预后标志物的研究

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中国医药指南 2025年第4期23卷 6-11页

作者：陈立松陈志钊谢镇国吴志国福建医科大学附属第二医院急诊科福建泉州362000

目的驱动蛋白20基因(KIF20B)在多种肿瘤中被发现,在肿瘤浸润中扮演着重要角色,但其在肺腺癌中的作用却很少被报道。本文的目的是根据癌症基因组图谱的数据显示KIF20B与肺腺癌之间的关系。方法采用Pearson χ^(2)检验、Fisher精确检验、... 详细信息

目的驱动蛋白20基因(KIF20B)在多种肿瘤中被发现,在肿瘤浸润中扮演着重要角色,但其在肺腺癌中的作用却很少被报道。本文的目的是根据癌症基因组图谱的数据显示KIF20B与肺腺癌之间的关系。方法采用Pearson χ^(2)检验、Fisher精确检验、t检验和Logistic回归等方法评估KIF20B与临床病理特征的关系。采用ROC曲线分析KIF20B对肺腺癌的诊断效果。通过Kaplan-Meier和Cox回归分析评估影响肺腺癌预后的因素。通过基因集富集分析和免疫浸润分析,阐明KIF20B可能潜在的生物学机制。结果KIF20B高表达与原发肿瘤范围(OR=1.91,T2/T3/T4 vs.T1,P<0.001)、局部淋巴结浸润(OR=1.61,N1/N2/N3 vs.N0,P=0.012)、分期(OR=1.80,Ⅱ期/Ⅲ期/Ⅳ期vs.Ⅰ期,P=0.001)、治疗结局(OR=1.57,PD/SD/PR ***,P=0.042)和TP53状态(OR=4.11,突变vs.野生,P<0.001)显著相关。KIF20B的受试者工作特征ROC曲线下面积为0.838。Kaplan-Meier生存分析显示,KIF20B高的肺腺癌预后更差(P=0.002)。单因素分析显示,KIF20B高与较差的总生存期显著相关(HR 1.586,95%CI 1.183~2.127,P=0.002)。多因素分析显示,高KIF20B与总生存期依然显著相关(HR 1.942,95%CI 1.281~2.942,P=0.002)。富集分析表明,KIF20B高表达与细胞周期检测点、细胞周期有丝分裂、有丝分裂纺锤体检测点、姐妹染色体融合分辨率和有丝分裂前中期相关。免疫浸润分析显示,KIF20B高表达与Th2细胞浸润呈正相关。结论KIF20B升高预示着肺腺癌预后不良。此外,细胞周期相关通路和Th2细胞浸润可能是KIF20B参与肺腺癌进展的机制。

关键词：驱动蛋白20基因预后肺腺癌生物信息学分析

Efficient production of ethyl levulinate from cassava over Al2(SO4)3 catalyst in ethanol–water system

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Journal of Energy Chemistry 2017年第1期26卷 115-120页

作者： Jin Tan Qiying Liu Lungang chen Tiejun Wang Longlong Ma Guanyi chen School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Renewable Energy Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640GuangdongChina Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640GuangdongChina

One-pot achievement of ethyl levulinate from cassava was conducted in ethanol–water system over several simple sulfate salt catalysts. Al2(SO4)3catalyst had the best performance in synthesizing ethyl levulinate comparing with those of a series of sulfate salts. The highest yields of ethyl levulinate was up to 39.27% as well as 7.78% levulinate acid when cassava was catalyzed in ethanol medium by adding 10 wt% water.13C and1H NMR spectroscopic investigations confirmed that isomerization of glucose to fructose over Al2(SO4)3catalyst is an important step in producing ethyl levulinate and levulinate acid. Due to aggregations of Al3+under hydrothermal conditions, tiny amount of Al3+were detected in filtrate at the percentage of 0.32% even if in absolute water. Brønsted and Lewis acids could improve the yield of ethyl levulinate and levulinate acid by synergistic effect. All results suggested that Al2(SO4)3was a simple and efficient catalyst for ethyl levulinate and levulinate acid production. © 2016 Science Press

关键词： Catalysts Ethanol Plants (botany) Sulfur compounds Waterworks

A study on the changes of dynamic feature code when fixing bugs: towards the benefits and costs of Python dynamic features

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Science China(Information Sciences) 2018年第1期61卷 169-186页

作者： Zhifei chen Wanwangying MA Wei LIN Lin chen Yanhui LI Baowen XU State Key Laboratory for Novel Software Technology Nanjing University

Dynamic features in programming languages support the modification of the execution status at runtime, which is often considered helpful in rapid development and prototyping. However, it was also reported that some dynamic feature code tends to be change-prone or error-prone. We present the first study that analyzes the changes of dynamic feature code and the roles of dynamic features in bug-fix activities for the Python language. We used an AST-based differencing tool to capture fine-grained source code changes from 17926 bug-fix commits in 17 Python projects. Using this data, we conducted an empirical study on the changes of dynamic feature code when fixing bugs in Python. First, we investigated the characteristics of dynamic feature code changes, by comparing the changes between dynamic feature code and non-dynamic feature code when fixing bugs, and comparing dynamic feature changes between bug-fix and non-bugfix activities. Second, we explored 226 bug-fix commits to investigate the motivation and behaviors of dynamic feature changes when fixing bugs. The study results reveal that(1) the changes of dynamic feature code are significantly related to bug-fix activities rather than non-bugfix activities;(2) compared with non-dynamic feature code, dynamic feature code is inserted or updated more frequently when fixing bugs;(3) developers often insert dynamic feature code as type checks or attribute checks to fix type errors and attribute errors;(4) the misuse of dynamic features introduces bugs in dynamic feature code, and the bugs are often fixed by adding a check or adding an exception handling. As a benefit of this paper, we gain insights into the manner in which developers and researchers handle the changes of dynamic feature code when fixing bugs.

关键词： Python fine-grained code changes change behaviors dynamic features bug fixing

Polar Motion of the Triaxial Nonrigid Earth and Atmospheric Excitation

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Geo-Spatial Information Science 2011年第3期14卷 223-229页

作者： chen Wei School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079 China State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University129 Luoyu RoadWuhan 430079 China Key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan University 129 Luoyu RoadWuhan 430079 China

The present study aims to extend the traditional rotation theory of the rotational-symmetric Earth to the triaxial Earth. We reormulate the Liouville equations and their general solutions for the triaxial nonrigid Earth and find that the traditional theory introduces some theoretical errors in modeling the excitation functions. Furthermore, we apply that theory to the atmospheric excitation and find that theoretical errors should not be neglected given the present measurement accuracy. Thus we conclude that the traditional theory of the rotation of the rotational-symmetric Earth should be revised and upgraded to include the effects of the Earth＇s triaxiality.

关键词： Earth rotation triaxiality of the Earth atmospheric excitation