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Hierarchical hollow Li4Ti5O12.urchin-like microspheres with ultra-high specific surface area for high rate lithium ion batteries

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Nano Research 2014年第7期7卷 1043-1053页

作者： Jin cheng Renchao Che Chongyun Liang Jiwei liu Min Wang Junjie Xu Department of Material Science and Laboratory of Advanced Materials Fudan University Shanghai 200438 China

Large specific surface area is critical for Li4Ti5O12.to achieve good rate capacity and cycling stability, since it can increase the contact area between electrolyte/ electrode and shorten the transport paths for electrons and lithium ions. In this study, hierarchical hollow Li4Ti5O12.urchin-like microspheres with ultra-high specific surface area of over 140 m2.g^-1 and diameter more than 500 nm have been successfully synthesized by combining the versatile sol-gel process and a hydrothermal reaction, and exhibit excellent electrochemical performance with a high specific capacity of 12. mA-h.g-1 at 2. C and long cycling stability of 〈 2. decay after 100 cycles. Ex situ electron energy loss spectroscopy （EELS） analysis of Li4Ti5O12.microspheres at different charge-discharge stages indicates that only a fraction of the TP＊ ions are reduced to Ti3＋ and a phase transformation occurs whereby the spinel phase Li4TisO12.is converted into the rock-salt phase Li7Ti5O12. Even after 100 cycles, the oxidation-reduction reaction between Ti3＋ and Ti4＋ can be carried out much more effectively on the surface of Li4Ti5O12.nanosheets than on commercially available Li4Ti5O12.particles. All the results suggest that these Li4Ti5O12.microspheres may be attractive candidate anode materials for lithium ion batteries.

关键词： Li4Ti5O12 urchin-like microspheres EELS electrochemicalperformance lithium ion batteries

Characteristics of mining gas channel expansion in the remote overlying strata and its control of gas flow

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International Journal of Mining Science and Technology 2013年第4期23卷 480-486页

作者： liu Hongyong cheng Yuanping Chen Haidong Mou Junhui Kong Shengli School of Safety Engineering China University of Mining & Technology National Engineering Research Center of Coal Gas Control China University of Mining & Technology Key Laboratory of Gas and Fire Control for Coal Mine China University of Mining & Technology Post-Doctoral Scientifc Research Station in Shanxi Coking Coal Group Co. Ltd.

The technology of pressure relief gas drainage is one of the most effective and economic for preventing gas emissions in underground *** on current understanding of strata breakage and fracture development in overlying strata,the current study divides the overlying strata into the following three longitudinal zones in terms of the state of gas flow:a turbulent channel zone,a transitional circulation channel zone and a seepage channel *** to the key strata discrimination theory of controlling the overlying strata,the calculation method establishes that the step-type expansion of the mining gas channel corresponds to the advancing distance of working face,and this research also confrms the expanding rule that the mining gas channel in overlying strata follows the advancing distance of mining working *** on the geological conditions of Xinjing Coal Mine of Yangquan,this paper researches the expanding rule of mining gas channel as well as the control action of the channel acting on the pressure relief flow under the condition of the remote protective layer,and got the distance using inversion that the step-type expanding of mining gas channel is corresponding to the advancing distance of working face,which verifes the accuracy and feasibility of theoretical calculation method proposed in this *** research provides the theoretical basis for choosing the technology of pressure relief gas drainage and designing the parameters of construction.

关键词： Remote mining overlying strata Gas channel expansion Gas flow Control action Key strata

First-Principle Calculations for Thermodynamic Properties of LiBC Under High Temperature and High Pressure

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Communications in Theoretical Physics 2006年第3X期46卷 573-576页

作者： liu Zhong-Li cheng Yan TAN Ni-Na GOU Qing-Quan Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The thermodynamic properties of LiBC are investigated by using the full-potential linearlzed muffin-tin orbital method （FP-LMTO） within the frame of density functional theory （DFT） and using the quasi-harmonic Debye model. The dependencies of the normalized lattice parameters a/a0 and c/c0, the ratio （c/a）/2. the normalized primitive volume V/V0 on pressure and temperature are successfully obtained. It is found that the interlayer covalent interactions （Li-B bonds or Li-C bonds） are more sensitive to temperature and pressure than intralayer ones （B-C bonds）, as gives rise to the extreme lattice anisotropy in the bulk hop LiBC.

关键词： thermal expansion heat capacity compressibility LiBC full-potential linearized muffin-tin orbital

True-data testbed for 5G/B5G intelligent network

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Intelligent and Converged Networks 2021年第2期2卷 133-149页

作者： Yongming Huang Shengheng liu cheng Zhang Xiaohu You Hequan Wu National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211111China China Information and Communication Technology Group Corporation Beijing 100083China

Future beyond fifth-generation(B5G)and sixth-generation(6G)mobile communications will shift from facilitating interpersonal communications to supporting internet of everything(IoE),where intelligent communications with full integration of big data and artificial intelligence(AI)will play an important role in improving network efficiency and providing high-quality *** a rapid evolving paradigm,the AI-empowered mobile communications demand large amounts of data acquired from real network environment for systematic test and ***,we build the world’s first true-data testbed for 5G/B5G intelligent network(TTIN),which comprises 5G/B5G on-site experimental networks,data acquisition&data warehouse,and AI engine&network *** the TTIN,true network data acquisition,storage,standardization,and analysis are available,which enable system-level online verification of B5G/6G-orientated key technologies and support data-driven network optimization through the closed-loop control *** paper elaborates on the system architecture and module design of *** technical specifications and some of the established use cases are also showcased.

关键词： true-data testbed wireless communication networks artificial intelligence(AI) big data internet of everything(IoE)

Wavelet-based multispectral face recognition

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Optoelectronics Letters 2008年第5期4卷 384-386页

作者： liu Dian-ting ZHOU Xiao-dan WANG cheng-wen CAD CG ＆ Network Laboratory School of Mechanical Engineering Dalian University of Technology Dalian 116024 China School of Electronic and lnformation Engineering Dalian University of Technology Dalian 116024 China Department of Labor Security Xiangying Town Government Dalian 116111 China.

This paper proposes a novel wavelet-based face recognition method using thermal infrared (IR) and visible-light face images. The method applies the combination of Gabor and the Fisherfaces method to the reconstructed IR and visible images derived from wavelet frequency subbands. Our objective is to search for the subbands that are insensitive to the variation in expression and in illumination. The classification performance is improved by combining the multispectal information coming from the subbands that attain individually low equal error rate. Experimental results on Notre Dame face database show that the proposed wavelet-based algorithm outperforms previous multispectral images fusion method as well as monospectral method.

关键词：子波装置识别方法红外线可见光

内蒙古中西部地区基层医护人员心理健康状况调查

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数理医药学杂志 2024年第3期37卷 164-170页

作者：刘灿李颖洁刘梦唐思源韩珂程景民山西医科大学公共卫生学院太原030001 山西医科大学管理学院太原030001 康复大学青岛中心医院(青岛市中心医疗集团)质控部山东青岛266000 康复大学青岛中心医院(青岛市中心医疗集团)医务部山东青岛266000 内蒙古科技大学包头医学院内蒙古包头014040 鄂尔多斯市疾病预防控制中心流行病科内蒙古鄂尔多斯017000

目的了解内蒙古中西部地区基层医护人员的心理健康状况及其影响因素,为有效开展基层医护人员的心理干预提供参考。方法采用分层整群抽样方法,抽取内蒙古中西部地区1409名基层医护人员,采用症状自评量表(SCL-90)对其进行问卷调查。结果... 详细信息

目的了解内蒙古中西部地区基层医护人员的心理健康状况及其影响因素,为有效开展基层医护人员的心理干预提供参考。方法采用分层整群抽样方法,抽取内蒙古中西部地区1409名基层医护人员,采用症状自评量表(SCL-90)对其进行问卷调查。结果内蒙古中西部地区基层医护人员心理异常阳性率为17.38%;抑郁、躯体化和敌对阳性率分别为2..11%、2..89%和19.31%;护士在躯体化、强迫、人际关系、抑郁、焦虑、敌对、恐惧7个因子得分上高于医生(P3次的基层医护人员心理健康状况较差(P<0.05);多重线性回归分析结果显示,月工资收入和夜班频次是影响基层医护人员心理健康状况的重要因素。结论内蒙古中西部地区基层医护人员总体心理健康水平不容乐观,需要加强心理健康教育,给予心理支持和疏导,切实提高其心理健康水平。

关键词：基层医护人员心理健康影响因素内蒙古中西部地区

Co-composting of Chinese milk vetch with rice straw and using the compost as a peat substitute of seeding substrate of vegetables

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 214-220页

作者： Yunfeng Chen cheng Hu Donghai liu Shuanglai Li Yan Qiao Key Laboratory of Fertilization from Agricultural Wastes Ministry of Agriculture and Rural AffairsWuhan 430064China Institute of Plant Protection and Soil Fertilizer Hubei Academy of Agricultural SciencesWuhan 430064China

Chinese milk vetch(Astragalussinicus L.)is an environment-friendly green manure used for rice with low carbon/nitrogen(C/N)ratio and high *** improve the added values of milk vetch,the feasibility of co-composting of milk vetch with rice straw was *** probability of using the milk vetch-based compost as a peat substitute in seeding substrate of vegetable was further *** changes in physicochemical properties during co-composting of milk vetch and rice straw were evaluated,depending on three treatments:(1)milk vetch alone(MV),(2.co-composting of milk vetch and rice straws with 4:1 ration(w/w)(MV+S)and(3)MV+S with the addition of 3%(w/w)microbial inoculation(MV+S+M).The entire composting durations were 15 d,2. d,and 2. d in MV,MV+S,MV+S+M *** to MV compost,both the MV+S,MV+S+M composts increased the temperature,pH,organic C,total nitrogen(N),total potassium(K)and the germination index(GI)(over 100)during the cooling/mature phase,and decreased total N loss,and generally,the improvements or reductions were greater in the MV+S+M compost than in the MV+S ***,the MV+S+M compost was added at a peat substitute rates of 0%,2.%,40%,80%and 100%in a pot experiment to testify the utilization of milk vetch-based compost in *** results showed that the substrate with 40%substitute rate increased the cabbage seeding growth,and that the electrical conductivity was the limiting factor of preventing the substitute rate *** pot experiment demonstrated that the substrate with 40%peat substitute increased the cucumber growth as compared to the substrate without *** conclusion,the co-composting milk vetch with rice straw was feasible and quick,and microbial inoculation accelerated the composting process and improved the compost *** milk vetch-based composts were nutrient-rich and safe,and thus,can replace part of peat in vegetable seeding substrate.

关键词： Chinese milk vetch(Astragalussinicus L.) compost peat seeding substrate

铬污染土壤动态浸出特征及对地下水影响的模拟

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南水北调与水利科技（中英文） 2024年第2期22卷 272-281页

作者：庄钧懿成一知侯一哲刘玉兰王锴程莉蓉丁爱中纪智慧徐巍王承刚北京师范大学水科学研究院北京100091 教育部地下水污染控制与修复工程研究中心北京100091 湖南新九方科技有限公司湖南株洲410001 北京金河水务建设集团有限公司北京102200 大连市生态环境事务服务中心辽宁大连116023

以原长沙铬盐厂污染土壤为研究对象,利用动态淋溶试验,研究不同淋溶模式下土壤六价铬[Cr(Ⅵ)]淋出特征及其对地下水的影响。结果显示,淋溶流速会影响土柱中Cr(Ⅵ)达到解吸稳定所需要的时间,即在连续淋溶模式的高、中、低3种流速条件下,... 详细信息

以原长沙铬盐厂污染土壤为研究对象,利用动态淋溶试验,研究不同淋溶模式下土壤六价铬[Cr(Ⅵ)]淋出特征及其对地下水的影响。结果显示,淋溶流速会影响土柱中Cr(Ⅵ)达到解吸稳定所需要的时间,即在连续淋溶模式的高、中、低3种流速条件下,达到平衡的时间分别为1、4、15 d,而间歇淋溶模式的Cr(Ⅵ)浸出效率略低于连续淋溶模式,这主要是受到土壤中孔隙水更新效率的控制。利用COMSOL Multiphysics?5.6构建试验中Cr(Ⅵ)迁移的模型,计算连续、间歇2.淋溶模式下6种不同情景中Cr(Ⅵ)的质量浓度变化及累积浸出质量,结合模型计算与柱实验结果分析发现,当土壤中Cr(Ⅵ)质量分数达到二类用地筛选值(5.7 mg/kg)后,淋出液中Cr(Ⅵ)质量浓度仍为地下水Ⅴ类水标准(0.1 mg/L),此时淋出液中Cr(Ⅵ)质量浓度仍对地下水环境造成威胁;同一时间段内,间歇淋溶柱高流速情景下有最小淋出率(33.67%),连续淋溶柱高流速情景有最大浸出率(83.99%)。研究表明,在场地地下水污染治理过程中,需要考虑土壤修复标准对地下水的影响,即水土共治。研究成果可为重金属污染场地修复工程提供参考。

关键词：六价铬水土共治地下水柱试验数值模拟

ON THE FEASIBILITY OF DETERMINING ELECTRON-NEUTRINO MASS FROM THE STUDY OF ELECTRON CAPTURE RATES IN ^(157)Tb

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Chinese Physics Letters 1984年第2期1卷 81-84页

作者： CHING cheng-rui HO Tso-hsiu liu Jia-lin Institute of Theoretical Physics Academia SinicaP.O.Box 2735BeijingChina

A comparison between the electron captures of 158Tb and 157Tb is presented. The practical merit of using 157Tb electron capture rates as a tool for electron-neutrino mass determination is analysed and emphasized.

关键词： RATE determination