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Spatial Impact of High-speed Railway on the Urban Scale:An Empirical Analysis from Northeast China

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Chinese Geographical Science 2020年第2期30卷 366-378页

作者： WANG Shaobo GUO Jianke LUO Xiaolong liu junfeng GU Zongni School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Center for Studies of Marine Economy and Sustainable Development Liaoning Normal UniversityDalian 116029China Faculty of Economics and Management East China Normal UniversityShanghai 200241China

The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and *** leads to either shrinkage or expansion of urban ***,research on the influence mechanisms of the urban scale has mostly concentrated on historical,economic and social *** influence of traffic factors is rarely mentioned in current ***,this study examines Northeast China,where the change in urban scale is most significant,to discuss the spatial impact of high-speed railway on the urban *** is of great significance in terms of enriching current understanding of the factors affecting the urban *** results included the following:1)The high-speed railway produced considerable space-time convergence effects,however,simultaneously aggravated the imbalance in traffic development in Northeast *** increase in accessibility presents attenuation characteristics from the high-speed ***,the high-speed railway has changed the mode of cooperation between cities in the provinces,inter-regional and inter-provincial cooperation models gradually become popular.2)The change rate of accessibility and the urban scale present significant spatial coupling phenomena,with the change rate of the Harbin-Dalian trunk lines and its surroundings being more significant.3)There are predominantly four modes of the influence of high-speed railway on the urban scale,which make difference city present expansion or shrinkage.

关键词： high-speed railway urban scale traffic accessibility spatial coupling GWR model

Reviews of emission of biogenic volatile organic compounds(BVOCs) in Asia

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Journal of Environmental Sciences 2020年第9期32卷 266-277页

作者： Xiaoxiu Lun Ying Lin Fahe Chai Chong Fan Hong Li junfeng liu College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China

Biogenic volatile organic compounds(BVOCs) in the atmosphere play important roles in the formation of ground-level ozone and secondary organic aerosol(SOA) in global scale and also in regional scale under some condition due to their large amount and relatively higher *** places with high plant cover in the tropics and in China where air pollution is serious,the effect of BVOCs on ozone and secondary organic aerosols is *** present research aims to provide a comprehensive review about the emission rate,emission inventory, research methods,the influencing factors of BVOCs emissions,as well as their impacts on atmospheric environment quality and human health in recent years in Asia based on the summary and analysis of *** is suggested to use field direct measurement method to obtain the emission rate and model method to calculate the emission *** recommendations are given for future investigation and policy development on BVOCs emission.

关键词： BVOCs pollution volatile

Heterogeneous oxidation of carbonyl sulfide on mineral oxides

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Chinese Science Bulletin 2007年第15期52卷 2063-2071页

作者： liu YongChun liu junfeng HE Hong YU YunBo XUE Li Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 China

Heterogeneous oxidation of carbonyl sulfide (OCS) on mineral oxides including SiO2,Fe2O3,CaO,MgO,ZnO and TiO2,which are the main components of atmospheric particles,were investigated using in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS),ion chromatography (IC),temperature-programmed desorption (TPD),X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) methods. The main products and intermediates of the heterogeneous oxidation of OCS on these oxides were identified with in situ DRIFTS and IC. The reaction mechanism and kinetics were also discussed. It is found that the reaction mechanism on these mineral oxides is the same as that on Al2O3 for the same final products and the intermediates at room temperature. Namely,OCS can be catalytically oxidized to produce surface SO42- species and gaseous CO2 through the surface hydrogen thiocarbonate (HSCO2-) and HSO3- species. The activity series for heterogeneous oxidation of OCS follows: Al2O3 ≈ CaO > MgO > TiO2 ≈ ZnO > Fe2O3 > SiO2. The specific area,basic hydroxyl and surface basicity of these oxides have effect on the reactivity. This study suggests that heterogeneous reactions of OCS on mineral dust may be an unneglectable sink of OCS.

关键词：羰基硫化物矿物氧化物硫酸盐反作用力

屎肠球菌F11.1G菌剂对断奶羔羊生长性能、营养物质表观消化率、屠宰性能、瘤胃发酵和瘤胃微生物区系的影响

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动物营养学报 2024年第5期36卷 3143-3155页

作者：朱振宇杨成王明根俄广旭刘俊峰卢冬郭雪峰塔里木大学动物科学与技术学院阿拉尔843300 塔里木畜牧科技兵团重点实验室阿拉尔843300

本试验旨在探究饲粮中添加屎肠球菌(Enterococcus faecium)F11.1G菌剂对卡拉库尔羊断奶羔羊生长性能、营养物质表观消化率、屠宰性能、瘤胃发酵和瘤胃微生物区系的影响。试验选取20只健康、2月龄、体重(21.0±1.0)kg的卡拉库尔羊断奶羔... 详细信息

本试验旨在探究饲粮中添加屎肠球菌(Enterococcus faecium)F11.1G菌剂对卡拉库尔羊断奶羔羊生长性能、营养物质表观消化率、屠宰性能、瘤胃发酵和瘤胃微生物区系的影响。试验选取20只健康、2月龄、体重(21.0±1.0)kg的卡拉库尔羊断奶羔羊,按体重配对原则分为对照组和试验组,每组10只。对照组饲喂基础饲粮,试验组每只羊每天在基础饲粮中添加2.0 g屎肠球菌F11.1G菌剂。试验期75 d,其中预试期15 d,正试期60 d。正试期第1天晨饲前称重记为初始体重,于正试期的第45~52天进行营养物质表观消化率的测定;正试期第60天,每组选取5只试验动物空腹称重后进行屠宰,测定屠宰性能、瘤胃发酵参数和瘤胃微生物区系。结果表明:试验组净增重和平均日增重(ADG)均极显著高于对照组(P<0.01),平均日采食量(ADFI)显著高于对照组(P<0.05),料重比(F/G)极显著低于对照组(P<0.01);试验组酸性洗涤纤维(ADF)表观消化率显著高于对照组(P<0.05);试验组宰前活重和胴体重显著高于对照组(P<0.05),肝脏指数、瘤胃指数、小肠指数和大肠指数显著或极显著高于对照组(P<0.05或P<0.01),皱胃指数显著低于对照组(P<0.05);从瘤胃发酵指标来看,饲粮中添加屎肠球菌F11.1G菌剂后,瘤胃中乙酸、丁酸浓度和乙酸/丙酸显著升高(P<0.05);从瘤胃微生物区系来看,饲粮中添加屎肠球菌F11.1G菌剂后,提高了瘤胃菌群操作分类单元(OTU)数目、拟杆菌门、厚壁菌门和纤维菌门相对丰度,理研菌科_RC9_肠道群相对丰度与ADG和pH、氨态氮(NH3-N)、乙酸、丙酸、丁酸、戊酸浓度呈正相关。综上所述,饲粮中添加2.0 g屎肠球菌F11.1G菌剂可以提高断奶羔羊生长性能、ADF表观消化率,通过增加瘤胃中乙酸和丁酸浓度改善瘤胃发酵,提高瘤胃细菌OTU数目,增加瘤胃细菌门水平中拟杆菌门、厚壁菌门和纤维菌门相对丰度,并且理研菌科_RC9_肠道群相对丰度与ADG和瘤胃发酵参数呈正相关。

关键词：屎肠球菌F11.1G 生长性能屠宰性能营养物质表观消化率瘤胃发酵瘤胃微生物区系

Au/LaVO_(4)Nanocomposite:Preparation,Characterization,and Catalytic Activity for CO Oxidation

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Nano Research 2008年第1期1卷 46-55页

作者： junfeng liu Wei Chen Xiangwen liu Kebin Zhou Yadong Li Department of Chemistry Tsinghua UniversityBeijing 100084China College of Chemistry and Chemical Engineering Graduate University of the Chinese Academy of SciencesBeijing 100049China

The size of the gold particles is a very important parameter to get active *** paper reports a novel colloidal deposition method to prepare Au/LaVO_(4)nanocomposite catalyst with monodispersed Au colloids and uniform LaVO_(4)nanoplates in nonpolar *** Au colloids with tunable size(such as 2,5,7,11,13,and 16 nm)and LaVO_(4)nanocrystals with well-defi ned shapes were pre-synthesized assisted with oleic acid/*** the following immobilization process,the particle size and shape of Au and LaVO_(4)were nearly ***-prepared Au/LaVO_(4)nanocomposite showed high catalytic activity for CO oxidation at room *** sizes of gold particles were well-defi ned before the immobilization process,size effect of gold particles was easy to be investigated and the results show that 5-nm Au/LaVO_(4)nanocomposite has the highest activity for CO *** synthetic method can be extended further for the preparation of other composite nanomaterials.

关键词： Au/LaVO_(4) nanocomposite colloidal deposition catalytic activity

Experimental studies on extraction of cobalt ions from dilute aqueous solutions by using complexation-ultrafiltration process

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Frontiers of Chemical Science and Engineering 2010年第3期4卷 360-366页

作者： Jianxian ZENG junfeng liu Niandong HUANG College of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China

The extraction of cobalt ions from dilute aqueous solutions was investigated by ultrafiltration with the help of poly(acrylic acid)sodium salt(PAASS).Polysulfone and polyethersulfone hollow fiber ultrafiltration membranes were employed in this *** kinetics of complexation reaction was studied for PAASS with Co^(2+).Results showed that,under a large excess of PAASS,it takes 65,55 and 40 min at pH 5,6 and 7,respectively,to get the equilibrium of *** reaction kinetics can be described by a pseudo-first-order ***,the effects of various parameters on the extraction of Co^(2+)were examined in *** indicated that loading ratio,pH value and low-molecular competitive complexing agent affect significantly cobalt rejection coefficient ***,a concentration experiment was carried out at pH *** increasing volume concentration factor,membrane flux declines slowly,and R value is always about *** concentrated retentate was used further for a decomplexation *** decomplexation ratio of cobalt-PAASS complex reaches as high as 90.1%.After the decomplexation step,a diafiltration experiment was performed at pH *** ions can be extracted satisfactorily from the retentate,and a purified PAASS is obtained.

关键词： cobaltion poly(acrylic acid)sodium salt complexation ultrafiltration extraction

基于标准IEC60870-5-101远动协议的配电线路故障监测终端测试工具的应用研究

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云南电力技术 2024年第3期52卷 80-83页

作者：徐万长刘俊峰李岚云南电力技术有限责任公司云南昆明650217

本文通过对基于标准IEC60870-5-101远动协议的配电线路故障监测终端测试工具的应用研究,建立了一种适用于配电网通信终端、故障指示器、单相接地故障辅助装置的101规约通信报文格式,实现了配电网故障监测终端通信统一、接口标准、功能... 详细信息

本文通过对基于标准IEC60870-5-101远动协议的配电线路故障监测终端测试工具的应用研究,建立了一种适用于配电网通信终端、故障指示器、单相接地故障辅助装置的101规约通信报文格式,实现了配电网故障监测终端通信统一、接口标准、功能规范。本测试工具在配电线路故障监测终端进行验收测试工作能充分发挥效能,避免不同厂家故障指示器标准不统一、技术不规范等问题,保证了故障监测终端运行的可靠性、数据传输的准确性、实时性,节约了大量运行维护的资金。

关键词：通信终端故障指示器验收测试

The magneto-thermoelectric effect of graphene with intra-valley scattering

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Chinese Physics B 2018年第9期27卷 504-511页

作者： Wenye Duan junfeng liu Chao Zhang Zhongshui Ma School of Physics Peking University Beijing 100871 China School of Physics University of Wollongong New South Wales 2522 Australia Department of Physics South University of Science and Technology of China Shenzhen 518055 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China

We present a qualitative and quantitative study of the magneto-thermoelectric effect of graphene. In the limit of impurity scattering length being much longer than the lattice constant, the intra-valley scattering dominates the charge and thermal transport. The self-energy and the Green＇s functions are calculated in the self-consistent Born approximation. It is found that the longitudinal thermal conductivity splits into double peaks at high Landau levels and exhibits oscillations which are out of phase with the electric conductivity. The chemical potential-dependent electrical resistivity, the thermal conductivities, the Seebeck coefficient, and the Nernst coefficient are obtained. The results are in good agreement with the experimental observations.

关键词： graphene thermoelectric transport thermal transport

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海上风电场吸力筒基础沉贯特性研究

岩土工程学报 2024年第3期46卷 655-661页

作者：王卫刘俊峰李亚静倪道俊滕华灯黄绍幸中国长江三峡集团有限公司科学技术研究院北京100038 三峡新能源阳江发电有限公司广东阳江529500 中国三峡新能源(集团)股份有限公司北京100053

吸力筒沉贯特性是影响其工程应用的重要因素。基于海上风电场吸力筒导管架基础筒体下沉过程的实测数据,研究真实海床地基条件下吸力筒沉贯阻力的CPT计算方法的可行性以及DNV规范推荐的土体沉贯阻力的经验系数的适用性,分析黏土层和砂土... 详细信息

吸力筒沉贯特性是影响其工程应用的重要因素。基于海上风电场吸力筒导管架基础筒体下沉过程的实测数据,研究真实海床地基条件下吸力筒沉贯阻力的CPT计算方法的可行性以及DNV规范推荐的土体沉贯阻力的经验系数的适用性,分析黏土层和砂土层中沉贯阻力的组成和负压下沉过程中的筒内土塞机制。研究结果表明:CPT计算方法能够较精确地计算吸力筒沉贯阻力,DNV规范推荐的经验系数高估了海床地基中淤泥质土、粉质黏土层的黏土经验系数k_(f)(z)以及砂砾、中砂、粗砂层等砂土经验系数k_(p)(z);负压下沉过程中,筒内土塞体积的发展规律与海床土层分布及土体物理力学性质密切相关。

关键词：海上风电吸力筒基础沉贯特性土塞