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基于过程-效应原理的循环经济评价方法及其实证研究 被引量:10
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作者 谢园园 傅泽强 +3 位作者 邬娜 吕宁磬 沈鹏 高宝 《生态经济》 CSSCI 北大核心 2015年第2期69-74,共6页
循环经济评价是循环经济理论研究的重要内容之一。因此,构建全面、科学的区域循环经济评价体系和方法具有重要的理论和实践指导意义。文章从系统论角度对循环经济进行解析的基础上,构建了基于过程—效应原理的区域循环经济评价指标体系... 循环经济评价是循环经济理论研究的重要内容之一。因此,构建全面、科学的区域循环经济评价体系和方法具有重要的理论和实践指导意义。文章从系统论角度对循环经济进行解析的基础上,构建了基于过程—效应原理的区域循环经济评价指标体系框架。基于循环经济评价指标体系框架,选取28个指标,采用熵值法综合评价和分析了我国2000~2011年循环经济发展动态,并将我国循环经济的发展历程划分为三个阶段:初步形成阶段、快速发展阶段以及全面推进形成规模阶段,从过程和效应两方面分析了影响循环经济发展的主导因素。 展开更多
关键词 循环经济 评价指标体系 过程-效应 熵值法
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中国城市居民出游的健康“动机-过程-效应”关系研究 被引量:1
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作者 龚胜生 纪文静 程绍文 《中国生态旅游》 CSCD 2024年第1期44-60,共17页
健康是人们出游的主要动机之一,旅游有益于旅游者的健康。为厘清中国城市居民出游的健康动机、旅游过程中的健康追求和旅游后的健康效应之间的关系,本文利用网络问卷调查获得全国121个城市1050个有效样本数据,进行描述统计分析与结构方... 健康是人们出游的主要动机之一,旅游有益于旅游者的健康。为厘清中国城市居民出游的健康动机、旅游过程中的健康追求和旅游后的健康效应之间的关系,本文利用网络问卷调查获得全国121个城市1050个有效样本数据,进行描述统计分析与结构方程模型分析,结果表明:追求健康是中国城市居民出游的主要动机之一;中国城市居民旅游后感知的健康效应主要来自旅游餐饮、旅游住宿和景区游览;中国城市居民出游的健康动机(包括身体健康动机和人际交往动机)正向影响他们旅游后感知的健康效应,身体健康动机产生的身心健康效应最大,人际交往动机产生的社会健康效应最大;中国城市居民旅游过程中对健康的追求在健康旅游动机与感知的旅游健康效应之间发挥着显著的中介作用。本研究所验证的中国城市居民旅游的“健康动机-过程-效应”(HMPE)理论模型清晰勾勒了旅游者健康动机驱动旅游过程中的健康追求、健康追求产生旅游健康效应的作用路径和因果关系。 展开更多
关键词 健康旅游动机 旅游健康追求 感知健康效应 动机-过程-效应 结构方程模型 中国城市居民
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Progress on Porous Ceramic Membrane Reactors for Heterogeneous Catalysis over Ultrafine and Nano-sized Catalysts 被引量:9
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作者 JIANG Hong MENG Lie CHEN Rizhi JIN Wanqin XING Weihong XU Nanping 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第2期205-215,共11页
Heterogeneous catalysts with ultrafine or nano particle size have currently attracted considerable attentions in the chemical and petrochemical production processes, but their large-scale applications remain challengi... Heterogeneous catalysts with ultrafine or nano particle size have currently attracted considerable attentions in the chemical and petrochemical production processes, but their large-scale applications remain challenging because of difficulties associated with their efficient separation from the reaction slurry. A porous ceramic membrane reactor has emerged as a promising method to solve the problem concerning catalysts separation in situ from the reaction mixture and make the production process continuous in heterogeneous catalysis. This article presents a review of the present progress on porous ceramic membrane reactors for heterogeneous catalysis, which covers classification of configurations of porous ceramic membrane reactor, major considerations and some important industrial applications. A special emphasis is paid to major considerations in term of application-oriented ceramic membrane design, optimization of ceramic membrane reactor performance and membrane fouling mechanism. Finally, brief concluding remarks on porous ceramic membrane reactors are given and possible future research interests are also outlined. 展开更多
关键词 porous ceramic membrane membrane reactor heterogeneous catalysis
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LIGAND EFFECT OF CATALYTIC SYSTEM WCl_6-Et_2Al FOR RING OPENING METATHESIS POLYMERIZATION OF DICYCLOPENTADIENE 被引量:1
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作者 Li Hong Wang Zheng He Binglin 《Chinese Journal of Reactive Polymers》 1997年第1期1-8,共8页
Ligand effect of the catalytic system WCl6-Et2AlCl for ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) was investigated. The experimental results show that adding sterically hindered phenol-2... Ligand effect of the catalytic system WCl6-Et2AlCl for ring opening metathesis polymerization (ROMP) of dicyclopentadiene (DCPD) was investigated. The experimental results show that adding sterically hindered phenol-2. 6-di-tert-butylcresylol(DTBC) in the catalytic system not only can obviously increase the monomer conversion of polymerization but also improve the mechanical properties, such as notched impact strength (NIS), tensile strength (TS) ect. 5 of the synthesized polyicycolpentadiene (PDCPD). A similar effect can be observed by using a sterically hindered polymeric phenol - linear phenol formaldehyde resin (LPF) as a ligand. 展开更多
关键词 Ring opening metathesis polymerization Polydicyclopentadiene Tungsten Dicyclopentadiene
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FE-based coupling simulation of Ti60 alloy in isothermal upsetting process 被引量:2
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作者 罗皎 李淼泉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期849-856,共8页
A constitutive equation was proposed to describe the effect of grain size on the deformation behavior.And a coupling simulation of deformation with heat transfer and microstructure was carried out in isothermal upsett... A constitutive equation was proposed to describe the effect of grain size on the deformation behavior.And a coupling simulation of deformation with heat transfer and microstructure was carried out in isothermal upsetting process of Ti60 alloy.The effects of processing parameters on the equivalent strain,the equivalent stress,the temperature rise and the grain size distribution in isothermal upsetting process of Ti60 alloy were analyzed.It is concluded that the uniformity of equivalent strain and equivalent stress increases with the increase of deformation temperature.However,the temperature rise and the grain size decreases with the increase of deformation temperature.The non-uniformity of equivalent strain,equivalent stress,temperature field and grain size increases with the increase of height reduction.And the calculated grain size using simulation is in good agreement with the experimental one. 展开更多
关键词 titanium alloy coupling simulation constitutive equation grain size
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Fabricating high-loading Fe-N4 single-atom catalysts for oxygen reduction reaction by carbon-assisted pyrolysis of metal complexes 被引量:1
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作者 Jun-Sheng Jiang He-Lei Wei +3 位作者 Ai-Dong Tan Rui Si Wei-De Zhang Yu-Xiang Yu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第5期753-761,共9页
Iron-based single-atom catalysts with nitrogen-doped carbon as support(Fe-SA/NPC)are considered effective alternatives to replace Pt-group metals for scalable application in fuel cells.However,synthesizing high-loadin... Iron-based single-atom catalysts with nitrogen-doped carbon as support(Fe-SA/NPC)are considered effective alternatives to replace Pt-group metals for scalable application in fuel cells.However,synthesizing high-loading Fe-SA catalysts by a simple procedure remains challenging.Herein,we report a high-loading(7.5 wt%)Fe-SA/NPC catalyst prepared by carbon-assisted pyrolysis of metal complexes.Both the nitrogen-doped porous carbon(NPC)support with high specific surface area and ο-phenylenediamine(o-PD)play key roles role in the preparation of high-loading Fe-SA/NPC catalysts.The results of X-ray photoelectron spectroscopy,high-angle annular dark-field scanning transmission electron microscopy,and X-ray absorption fine structure spectroscopy experiments show that the Fe atoms are anchored on the carbon carriers in a single-atom site configuration and coordinated with four of the doped nitrogen atoms of the carbon substrates(Fe-N_(4)).The activities of the Fe-SA/NPC catalysts in the oxygen reduction reaction increased with increasing iron loading.The optimized 250Fe-SA/NPC-800 catalyst exhibited an onset potential 0.97 V of and a half-wave potential of 0.85 V.Our study provides a simple approach for the large-scale synthesis of high-loading single-atom catalysts. 展开更多
关键词 Fe-N_(4)single-atom catalysts Oxygen reduction reaction High-loading Coordinated effect Four-electron transfer process
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Quantum Non-thermal Effect from Black Holes Surrounded by Quintessence
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作者 GONG Tian-Xi WANG Yong-Jiu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期974-976,共3页
We present a short and direct derivation of Hawking radiation as a tunneling process across the horizonand compute the tunneling probability.Considering the self-gravitation and energy conservation,we use the Keski-Va... We present a short and direct derivation of Hawking radiation as a tunneling process across the horizonand compute the tunneling probability.Considering the self-gravitation and energy conservation,we use the Keski-Vakkuri,Kraus,and Wilczek(KKW)analysis to compute the temperature and entropy of the black holes surrounded byquintessence and obtain the temperature and entropy are different from the Hawking temperature and the Bekenstein-Hawkingentropy.The result we get can offer a possible mechanism to deal with the information loss paradox becausethe spectrum is not purely thermal. 展开更多
关键词 hawking radiation QUINTESSENCE black hole
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Effects of Co_3O_4 nanocatalyst morphology on CO oxidation:Synthesis process map and catalytic activity 被引量:6
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作者 曾良鹏 李孔斋 +2 位作者 黄樊 祝星 李宏程 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期908-922,共15页
This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hy... This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies(i.e.,nanorods,nanosheets,and nanocubes) were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures(≤ 140℃).Nanorods can be synthesized in CoCl2 solution,while Co(NO3)2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature(higher than 140 ℃) results in the formation of nanocubes in either Co(NO3)2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^(3+) on the surface,much higher reducibility,and better oxygen desorption capacity. 展开更多
关键词 Cobalt oxide nanocatalyst Synthesis process map Morphology effect Catalytic activity Carbon monoxide oxidation
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Effects of Assistant Solvents and Mixing Intensity on the Bromination Process of Butyl Rubber 被引量:1
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作者 王伟 邹海魁 +3 位作者 初广文 向阳 彭晗 陈建峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第4期398-404,共7页
A slow bromination process of butyl rubber (IIR) suffers from low efficiency and low selectivity (S) of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixin... A slow bromination process of butyl rubber (IIR) suffers from low efficiency and low selectivity (S) of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixing inten-sity on the bromination process were systemically studied in this paper. The reaction process was found constantly accelerated with the increasing dosage and polarity of assistant solvent. Hexane with 30%(by volume) dichloro-methane was found as the suitable solvent component, where the stable conversion of 1,4-isoprene transferring to target product (xA1s) of 80.2%and the corresponding S of 91.2%were obtained in 5 min. The accelerated reaction process was demonstrated being remarkably affected by mixing intensity until the optimal stirring rate of 1100 r&#183;min-1 in a stirred tank reactor. With better mixing condition, a further intensification of the process was achieved in a ro-tating packed bed (RPB) reactor, where xA1s of 82.6% and S of 91.9% were obtained in 2 min. The usage of the suitable solvent component and RPB has potential application in the industrial bromination process intensification. 展开更多
关键词 bromination of butyl rubber process intensitication assistant solvent mixing intensity
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Magnetic Effects in the Thermodynamics of the Process of Thinking
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作者 Aibassov Yerkin Zhakenovlch Savizky Ruben +4 位作者 Yemelyanova Valentina Shakieva Tatyana Tussupbaev Nessipbay Bulenbayev Maxat Blagikh Evgeniy 《Journal of Chemistry and Chemical Engineering》 2016年第4期167-169,共3页
The authors have shown that the process of information and thinking can be modeled on the basis of chemical thermodynamics. The authors offer general equations to calculate the thinking of the work of judgment the L a... The authors have shown that the process of information and thinking can be modeled on the basis of chemical thermodynamics. The authors offer general equations to calculate the thinking of the work of judgment the L and of entropy solutions G in the presence of a magnetic field. As a result, studies have shown that the magnetic effects strongly influence the thermodynamics of the process of thinking. 展开更多
关键词 Magnetic effect THERMODYNAMICS process of thinking Shonon equation.
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Interfacial Shear Stress of Stratified Flow in a Horizontal Pipe 被引量:1
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作者 李卫东 孙科霞 周芳德 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第3期263-270,共8页
Experimental data are presented for the void fraction and the shear stresses of stratified gas-liquid flow in a pipe. A new technique was used to measure the interface shear stress. The interfacial shear stress was de... Experimental data are presented for the void fraction and the shear stresses of stratified gas-liquid flow in a pipe. A new technique was used to measure the interface shear stress. The interfacial shear stress was determined by using two methods: a momentum balance of gas and an extrapolation of the Reynolds shear stress profile at the gas-liquid interface. A new formula , relating to the interfacial friction factor with the void fraction and superficial gas Reynold number, was developed to predict the interface shear stress . The predicted values are in good agreement with experimental data. 展开更多
关键词 interfacial shear stress stratified flow laser doppler velocitometer
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钢悬链线立管强度可靠性计算研究
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作者 张萌 李智博 +2 位作者 吴剑国 张国进 孙政策 《海洋工程》 CSCD 北大核心 2018年第5期121-127,共7页
在钢悬链线立管分析中,材料性能、载荷参数、计算方法等都存在着大量不确定性。为考虑不确定性因素造成的影响,采用作用效应-抗力半随机过程构建可靠性模型,并采用极小化变换转化为静态可靠性问题。选用物理含义较为明确的屈服判定准则... 在钢悬链线立管分析中,材料性能、载荷参数、计算方法等都存在着大量不确定性。为考虑不确定性因素造成的影响,采用作用效应-抗力半随机过程构建可靠性模型,并采用极小化变换转化为静态可靠性问题。选用物理含义较为明确的屈服判定准则建立功能函数,通过单样本K-S检验对载荷随机过程的概率特性进行极值统计,提出载荷转化的方法以实现与目标可靠性指标的比对,并引入模型和主观不确定性随机变量。在此基础上采用改进的一次二阶矩法,对立管的强度可靠性进行了计算。结果表明此方法与利用系数方法能够相互印证,可以为立管的可靠性计算提供参考。 展开更多
关键词 钢悬链线立管 可靠性 作用效应-抗力半随机过程 极值统计 不确定性随机变量
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A "Trojan" in Climatic Change: The Urban Effect
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作者 J. Quereda Sala E. Monton Chiva J. Escrig Barbera 《Journal of Environmental Science and Engineering》 2011年第11期1526-1536,共11页
This paper sets out the preliminary results of an experimental research plan aimed at analysing the thermal processes inherent to the urbanisation effect. Although this effect is undeniable, the extent of its impact i... This paper sets out the preliminary results of an experimental research plan aimed at analysing the thermal processes inherent to the urbanisation effect. Although this effect is undeniable, the extent of its impact is a matter of controversy. The results obtained in this study show both the nature of the phenomenon and its considerable magnitude. Failure to take this process into account might seriously bias any analysis of thermal evolution, the cornerstone of the climate change hypothesis. 展开更多
关键词 TEMPERATURES urban heat island effect (UHI) HOMOGENEITY climatic change.
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Numerical analysis of temperature rise within 70MPa composite hydrogen vehicle cylinder during fast refueling 被引量:1
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作者 王亮 郑传祥 +2 位作者 李蓉 陈冰冰 魏宗新 《Journal of Central South University》 SCIE EI CAS 2014年第7期2772-2778,共7页
The numerical simulation model for predicting fast filling process of 70 MPa type Ⅲ(with metal liner) hydrogen vehicle cylinder was presented,which has considered turbulence,real gas effect and solid heat transfer is... The numerical simulation model for predicting fast filling process of 70 MPa type Ⅲ(with metal liner) hydrogen vehicle cylinder was presented,which has considered turbulence,real gas effect and solid heat transfer issues.Through the numerical analysis method,the temperature distributions of the gas within the solid walls were revealed; adiabatic filling was studied to evaluate the heat dissipation during the filling; the influences of various filling conditions on temperature rise were analyzed in detail.Finally,cold filling was proposed to evaluate the effect on temperature rise and SoC(state of charge) within the cylinder.The hydrogen pre-cooling was proved to be an effective solution to reduce maximum temperature and acquire higher SoC during the filling process. 展开更多
关键词 fast filling numerical analysis temperature rise hydrogen vehicle cylinder state of charge
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Static and Dynamic Study of a Wind Turbine Blade with Horizontal Axis
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作者 H. Hamdi C. Mrad +1 位作者 R. Nasri A. Hamdi 《Journal of Environmental Science and Engineering》 2011年第9期1167-1174,共8页
In this work the authors present a calculation process of the blades for wind turbine with horizontal axis. It is about a blade discretized by the finite element method (FEM) in order to determine the gyroscopic eff... In this work the authors present a calculation process of the blades for wind turbine with horizontal axis. It is about a blade discretized by the finite element method (FEM) in order to determine the gyroscopic effect during its rotation at a high speed. A blade must have the maximum output and resist to aerodynamic loads distributed over its length, which are related to its geometrical characteristics and the speed of the wind. For that, the authors wrote the relations whom determine these loads according to the flow speed of the wind, then, the authors integrated them in the laws of structure mechanics to obtain the motion equations of the blade. This process was applied to a twisted blade with a length of 1.9 m, built out of pressed aluminum sheet with a profile of the type NACA; this profile gives the best aerodynamic output. This blade is an element of a three-bladed propeller for wind turbine of maximum power 5 kW. Finally, we visualized its deformations and then the authors checked its holding in service. 展开更多
关键词 Wind turbine aerodynamic load static and dynamic behavior gyroscopic effect.
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Purification Processes and Market Potential of Bromelain in Brazil
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作者 Diego de Freitas Coelho Edgar Silveira Elias Basile Tambourgi 《Journal of Chemistry and Chemical Engineering》 2014年第9期882-888,共7页
Bromelain is the denomination given to the group of endoproteases obtained from members of Bromeliacea family. These enzymes have a wide range of proven applications and have been an object of study for worldwide rese... Bromelain is the denomination given to the group of endoproteases obtained from members of Bromeliacea family. These enzymes have a wide range of proven applications and have been an object of study for worldwide researchers for decades. Over the years, several different downstream processes were studied in order to determine which technique would be worthwhile to be implemented in Brazil and provide the national market with such product. The objective of the present study is to relate the main studies in Brazil that has proven that bromelain purification can be cost-effective, in addition to the well-known benefits owned by such enzymes, and highlight the applications that create their market potential in the Brazilian market. 展开更多
关键词 BROMELAIN market potential downstream processing liquid-liquid extraction aqueous two-phase systems.
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3D Simulation of Storm Surge Disaster Based on Scenario Analysis
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作者 王晓玲 孙小沛 +3 位作者 张胜利 孙蕊蕊 李瑞金 朱泽彪 《Transactions of Tianjin University》 EI CAS 2016年第2期110-120,共11页
The occurrence of storm surge disaster is often accompanied with floodplain, overflow, dike breach and other complex phenomena, while current studies on storm surge flooding are more concentrated on the 1D/2D numerica... The occurrence of storm surge disaster is often accompanied with floodplain, overflow, dike breach and other complex phenomena, while current studies on storm surge flooding are more concentrated on the 1D/2D numerical simulation of single disaster scenario(floodplain, overflow or dike breach), ignoring the composite effects of various phenomena. Therefore, considering the uncertainty in the disaster process of storm surge, scenario analysis was firstly proposed to identify the composite disaster scenario including multiple phenomena by analyzing key driving forces, building scenario matrix and deducing situation logic. Secondly, by combining the advantages of k-ω and k-ε models in the wall treatment, a shear stress transmission k-ω model coupled with VOF was proposed to simulate the 3D flood routing for storm surge disaster. Thirdly, risk degree was introduced to make the risk analysis of storm surge disaster. Finally, based on the scenario analysis, four scenarios with different storm surge intensity(100-year and 200-year frequency) were identified in Tianjin Binhai New Area. Then, 3D numerical simulation and risk map were made for the case. 展开更多
关键词 SIMULATION storm surge disaster scenario analysis risk degree 3D SST k-ω turbulence model composite scenario
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Control measures for thermal effects during placement of span-scale girder segments on continuous steel box girder bridges 被引量:3
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作者 Jin-feng WANG Jiang-tao ZHANG +1 位作者 Zhong-xuan YANG Rong-qiao XU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2020年第4期255-267,共13页
In this study, we examined the thermal effects throughout the process of the placement of span-scale girder segments on a 6×110-m continuous steel box girder in the Hong Kong-Zhuhai-Macao Bridge. Firstly, when a ... In this study, we examined the thermal effects throughout the process of the placement of span-scale girder segments on a 6×110-m continuous steel box girder in the Hong Kong-Zhuhai-Macao Bridge. Firstly, when a span-scale girder segment is temporarily stored in the open air, temperature gradients will significantly increase the maximum reaction force on temporary supports and cause local buckling at the bottom of the girder segment. Secondly, due to the temperature difference of the girder segments before and after girth-welding, some residual thermal deflections will appear on the girder segments because the boundary conditions of the structure are changed by the girth-welding. Thirdly, the thermal expansion and thermal bending of girder segments will cause movement and rotation of bearings, which must be considered in setting bearings. We propose control measures for these problems based on finite element method simulation with field-measured temperatures. The local buckling during open-air storage can be avoided by reasonably determining the appropriate positions of temporary supports using analysis of overall and local stresses. The residual thermal deflections can be overcome by performing girth-welding during a period when the vertical temperature difference of the girder is within 1 °C, such as after 22:00. Some formulas are proposed to determine the pre-set distances for bearings, in which the movement and rotation of the bearings due to dead loads and thermal loads are considered. Finally, the feasibility of these control measures in the placement of span-scale girder segments on a real continuous girder was verified: no local buckling was observed during open-air storage;the residual thermal deflections after girth-welding were controlled within 5 mm and the residual pre-set distances of bearings when the whole continuous girder reached its design state were controlled within 20 mm. 展开更多
关键词 Steel box girder Span-scale girder segments Construction process Thermal effects Control measures
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Tuning Zn^(2+) coordination tunnel by hierarchical gel electrolyte for dendrite-free zinc anode 被引量:12
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作者 Bingyao Zhang Liping Qin +5 位作者 Yun Fang Yizhao Chai Xuesong Xie Bingan Lu Shuquan Liang Jiang Zhou 《Science Bulletin》 SCIE EI CSCD 2022年第9期955-962,M0004,共9页
Aqueous zinc-ion batteries(ZIBs)are perceived as one of the most upcoming grid-scale storage systems.However,the issues of electrode dissolution,dendrite formation,and corrosion in traditional liquid electrolytes have... Aqueous zinc-ion batteries(ZIBs)are perceived as one of the most upcoming grid-scale storage systems.However,the issues of electrode dissolution,dendrite formation,and corrosion in traditional liquid electrolytes have plagued its progress.In this work,Zn dendrite growth and side reactions are effectively suppressed by a highly-confined tannic acid(TA)modified sodium alginate(SA)composite gel electrolyte(TA-SA).The ion-confinement effect is enhanced by divalent zinc ions coordinated with carboxyl groups and chelated with phenolic hydroxyl groups,thus guiding and regulating Zn deposition to achieve steady zinc plating/stripping behavior.As a consequence,the Zn/TA-SA/NH_(4)V_(4)O_(10) full cells deliver a high specific capacity of 238.6 mAh g^(-1) and maintain 94.51%over 900 cycles at 2 A g^(-1).Notably,after resting over 5 d,the capacity can be stabilized with a capacity retention of 97.25%after 200 cycles at 2 A g^(-1).This highlyconfined and hydrogen bond-strengthened gel electrolyte may provide an effective strategy for the future development of quasi-solid-state metal batteries. 展开更多
关键词 Natural polymers Hydrogel electrolytes Cycling stability SELF-DISCHARGE Aqueous zinc-ion batteries
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In situ FT-IR investigation on the reaction mechanism of visible light photocatalytic NO oxidation with defective g-C_3N_4 被引量:11
20
作者 Hong Wang Wenjie He +2 位作者 Xing’an Dong Haiqiang Wang Fan Dong 《Science Bulletin》 SCIE EI CAS CSCD 2018年第2期117-125,共9页
The g-C_3N_4 with different structures was prepared by heat treatment using urea(CN-U) and thiourea(CN-T) as precursors under the same conditions. The microstructure and optical properties of the photocatalyst were an... The g-C_3N_4 with different structures was prepared by heat treatment using urea(CN-U) and thiourea(CN-T) as precursors under the same conditions. The microstructure and optical properties of the photocatalyst were analyzed with advanced tools. The results showed that the CN-U has a porous structure, a high specific surface area and a wide band gap in comparison with CN-T. The in situ FT-IR technique was used to monitor the adsorption and reaction process of visible photocatalytic NO oxidation on g-C_3N_4. The corresponding reaction mechanism was proposed based on the results of reaction intermediate observation and electron paramagnetic resonance(EPR) radical scavenging. It was revealed that(1) the presence of defective sites favored the adsorption of gas molecules and electronically compensated it leading to promoted formation of the final products;(2) the high separation efficiency of photogenerated electron-hole pairs enhanced the production of radicals during the photocatalytic reaction;(3) the hydroxyl radicals(-OH) are not selective for the decomposition of pollutants, which are favorable to the complete oxidation of the reaction intermediates. The above three aspects are the main reasons for the CN-U possessing the efficient visible light photocatalytic activity. The present work could provide new insights and methods for understanding the mechanism of photocatalysis. 展开更多
关键词 g-C3N4 Visible light photocatalysis Defects In situ FT-IR Reaction mechanism
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