检索结果-南通市图书馆

Nano-Micro Letters 2025年第2期17卷 169-186页

作者： Bitgaram Kim Myeong‑Chang Sung Gwang‑Hee Lee Byoungjoon Hwang Sojung Seo Ji‑Hun Seo Dong‑Wan Kim department of Materials Science and engineering Korea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea School of civil Environmental and Architectural EngineeringKorea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea Materials Science and Chemical engineering Center Institute for Advanced Engineering(IAE)Yongin 17180Republic of Korea

A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety *** study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves ***-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain *** this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 *** situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen *** situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability *** present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.

关键词： Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain

Effect of abutment modeling on the seismic response ofbridge structures

在线全文

学校读者我要写书评

暂无评论

Earthquake engineering and engineering Vibration 2008年第4期7卷 395-402页

作者： Ady Aviram Kevin R.Mackie Bozidar Stojadinovic department of civil and environmental engineering University of CaliforniaBerkeley department of civil and environmental engineering University of Central Florida

Abutment behavior significantly influences the seismic response of certain bridge structures. Specifically in the case of short bridges with relatively stiff superstructures typical of highway overpasses, embankment mobilization and inelastic behavior of the soil material under high shear deformation levels dominate the response of the bridge and its column bents. This paper investigates the sensitivity of bridge seismic response with respect to three different abutment modeling approaches. The abutment modeling approaches are based on three increasing levels of complexity that attempt to capture the critical components and modes of abutment response without the need to generate continuum models of the embankment, approach, and abutment foundations. Six existing reinforced concrete bridge structures, typical of Ordinary Bridges in California, are selected for the analysis. Nonlinear models of the bridges are developed in OpenSees. Three abutment model types of increasing complexity are developed for each bridge, denoted as roller, simplified, and spring abutments. The roller model contains only single-point constraints. The spring model contains discrete representations of backfill, bearing pad, shear key, and back wall behavior. The simplified model is a compromise between the efficient roller model and the comprehensive spring model. Modal, pushover, and nonlinear dynamic time history analyses are conducted for the six bridges using the three abutment models for each bridge. Comparisons of the analysis results show major differences in mode shapes and periods, ultimate base shear strength, as well as peak displacements of the column top obtained due to dynamic excitation. The adequacy of the three abutment models used in the study to realistically represent all major resistance mechanisms and components of the abutments, including an accurate estimation of their mass, stiffness, and nonlinear hysteretic behavior, is evaluated. Recommendations for abutment modeling

关键词： embankment backfill shear keys bearing pads nonlinear analysis

Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期 152-156页

作者： Lihua Zhang Lingjing Chen Huatian Shi Yue Wei Gui Chen Tai-Chu Lau School of Environment and civil engineering Research Center for Eco-environmental Engineering Dongguan University of Technology department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

关键词：

同方期刊数据库

Nonlinear dynamic analysis of multi-base seismically isolated structures with uplift potentialⅡ:verification examples

在线全文

学校读者我要写书评

暂无评论

Earthquake engineering and engineering Vibration 2010年第1期9卷 83-91页

作者： Panayiotis C.Roussis Panos C.Tsopelas Michael C.Constantinou department of civil and environmental engineering University of Cyprus department of civil engineering University of Thessaly department of civil Structural and Environmental EngineeringUniversity at BuffaloState University of New York

The work presented in this paper serves as numerical verification of the analytical model developed in the companion paper for nonlinear dynamic analysis of multi-base seismically isolated structures. To this end, two numerical examples have been analyzed using the computational algorithm incorporated into program 3D-BASIS-ME-MB, developed on the basis of the newly-formulated analytical model. The first example concerns a seven-story model structure that was tested on the earthquake simulator at the university at Buflhlo and was also used as a verification example for program SAP2000. The second example concerns a two-tower, multi-story structure with a split-level seismic-isolation system. For purposes of verification, key results produced by 3D-BASIS-ME-MB are compared to experimental results, or results obtained from other structural/finite element programs. In both examples, the analyzed structure is excited under conditions of bearing uplift, thus yielding a case of much interest in verifying the capabilities of the developed analysis tool.

关键词： seismic isolation nonlinear dynamic analysis uplift verification multiple superstructures/bases

Coagulation enhanced electrokinetic settling of mature fine oil sands tailings

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2019年第2期29卷 199-208页

作者： Shriful Islam Julie Q.Shang department of civil and environmental engineering The University of Western Ontario department of civil and environmental engineering Shahjalal University of Science and Technology

The mature fine oil sand tailings(MFT) remain as slurry in the tailings pond for long time. The dewatering and consolidation of MFT for sustainable management is an important task for the mining industry. The objective of this study is to accelerate electrokinetic settling of MFT solids in suspensions in presence of optimal coagulant. In the first phase, optimal coagulant and coagulant dosage for settling of suspension are identified, i.e., ferric chloride at 350 mg/L. It is found that the chemical treatment is not much effective; the final solid content of the sediment is only 6.48% from an initial of 5%. In the second phase,combined coagulation and electrokinetic treatment is carried out to enhance the settling effect. The direct electric current is applied in continuous and intermittent modes on MFT suspensions placed in electrokinetic cell. The results show the final solid content reaches 23.74% under the combined application of350 mg/L ferric chloride and 218.75 V/m applied voltage gradient in the continuous mode. The intermittent current mode with 40% save in power consumption produces a settled sediment having 20.84% final solid content.

关键词： Electrokinetics Electrophoresis Coagulation Settling Voltage gradient MFT

Comparative Analysis of Tsunami Casualty Estimation Approaches: Agent-Based Modeling versus Simplified Approach in Japanese Coastal Cities

在线全文

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2024年第5期15卷 719-737页

作者： Tomoyuki Takabatake Nanami Hasegawa Keita Yamaguchi Miguel Esteban department of civil and environmental engineering Kindai University department of civil and environmental engineering Waseda University

Estimating potential casualties from a significant earthquake and tsunami event is crucial to enhance disaster preparedness and response. Although various approaches exist to assess potential casualties, few studies have made direct comparisons between them. The present study aimed to clarify the diff erences in the estimation of casualties between an agent-based model(ABM), which can capture detailed evacuation behavior but demands significant computational resources, and a simplified approach at less computational cost by assuming that evacuees would move along a straight line from their initial location to the closest evacuation destination. These diff erent approaches were applied to three coastal cities in Japan—Mihama,Kushimoto, and Shingu in Wakayama Prefecture—revealing significant diff erences in the estimated results between the ABM and the simplified approach. Notably, when the eff ects of building collapse due to an earthquake were considered, the mortality rates estimated by the ABM were higher than those estimated by the simplified approach in the three cities. There were also significant diff erences in the spatial distribution of the estimated mortality rates between the ABM and the simplified approach. The findings suggest that while the simplified approach can yield results more quickly, casualty estimates derived from such models should be interpreted with caution.

关键词： Agent-based modeling Building collapse Casualty estimation Evacuation Japan, Tsunami

Properties of Chemically Synthesized Nano-geopolymer Cement based Self-Compacting Geopolymer Concrete(SCGC)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan university of Technology(Materials Science) 2019年第1期34卷 98-106页

作者： Muhammad Ali Sikandar Byung Wan Jo Zafar Baloch Muhammad Asad Khan department of civil and environmental engineering Hanyang University department of civil and environmental engineering CECOS University

The physical and mechanical properties of self-compacting geopolymer concrete(SCGC) using chemically synthesized nano-geopolymer cement was investigated. Nano-geopolymer cement was synthesized using nano-silica, alkali activator, and sodium aluminate in the laboratory. Subsequently, nine nanogeopolymer cement sbased SCGC mixes with varying nano-geopolymer cement content, alkali activator content, coarse aggregate(CA) content, and curing temperature were produced. The workability-related fresh properties were assessed through slump flow diameter and slump flow rate measurements. Mechanical performances were evaluated through compressive strength, splitting tensile strength, and modulus of elasticity measurements. In addition, rapid chloride penetration test, water absorption, and porosity tests were also performed. It was assessed that all mix design parameters influenced the fresh and hardened properties of SCGC mixes. Based on test results, it was deduced that nano-geopolymer cement SCGC performed fairly well. All the SCGC mixes achieved the 28-day compressive strength in the range of 60-80 MPa. Additionally, all mixes attained 60% of their 28-day strength during the first three days of elevated temperature curing. FTIR and SEM analyses were performed to evaluate the degree of polymerization and the microstructure respectively for SCGC mixes.

关键词： geopolymer compressive strength self-compacting concrete alkali activator nano-silica

River management system development in Asia based on Data Integration and Analysis System(DIAS) under GEOSS

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2015年第1期58卷 76-95页

作者： Toshio KOIKE Petra KOUDELOVA Patricia Ann JARANILLA-SANCHEZ Asif Mumtaz BHATTI Cho Thanda NYUNT Katsunori TAMAGAWA department of civil engineering River and Environmental Engineering Laboratorythe University of Tokyo department of civil and environmental engineering Hydraulic Engineering LaboratoryHiroshima University

This paper introduces the process of development and practical use implementation of an advanced river management system for supporting integrated water resources management practices in Asian river basins under the framework of GEOSS Asia water cycle initiative （AWCI）. The system is based on integration of data from earth observation satellites and in-situ networks with other types of data, including numerical weather prediction model outputs, climate model outputs, geographical infor- mation, and socio-economic data. The system builds on the water and energy budget distributed hydrological model （WEB-DHM） that was adapted for specific conditions of studied basins, in particular snow and glacier phenomena and equipped with other functions such as dam operation optimization scheme and a set of tools for climate change impact assess- ment to be able to generate relevant information for policy and decision makers. In situ data were archived for 18 selected ba- sins at the Data Integration and Analysis System （DIAS） of Japan and demonstration projects were carded out showing poten- tial of the new system. It included climate change impact assessment on hydrological regimes, which is presently a critical step for sound management decisions. Results of such three case studies in Pakistan, Philippines, and Vietnam are provided here.

关键词： integrated water resources management tools climate change impact assessment Asian river basins Asian Water Cycle Initiative

Seismic performance and global ductility of RC frames rehabilitated with retrofi tted joints by CFRP laminates

在线全文

学校读者我要写书评

暂无评论

Earthquake engineering and engineering Vibration 2014年第1期13卷 59-73页

作者： M.Fakharifar M.K. Sharbatdar Z.Lin A.Dalvand A.Sivandi-Pour G.Chen department of civil Architectural and Environmental EngineeringMissouri University of Science and Technology department of civil engineering Semnan University department of civil and environmental engineering North Dakota State University

This paper presents a new FRP retrofi tting scheme to strengthen local beam-column joints in reinforced concrete(RC) *** new retrofi tting scheme was proposed following a preliminary study of four different existing retrofi tting schemes.A numerical simulation was conducted to evaluate the effectiveness of FRP-strengthened reinforced concrete frames by bridging behavior of local joints to the whole *** confi nement effects due to varying retrofi tting schemes in the joints were simulated in the frame *** seismic behavior factor was used to evaluate the seismic performance of the strengthened RC *** results demonstrated that the new proposed retrofi tting scheme was robust and promising,and fi nite element analysis appropriately captured the strength and global ductility of the frame due to upgrading of the local joints.

关键词： beam-column joints behavior factor retrofit FRP dynamic analysis seismic performance

Characterizing the Seasonal and Directional Varying Properties in A Marine Environment

在线全文

学校读者我要写书评

暂无评论

China Ocean engineering 2016年第4期30卷 549-564页

作者：张熠程涛 department of civil & environmental engineering Nanyang Technological University department of civil & environmental engineering Hubei Polytechnic of Technology

With noticing an increasing number of failure events for offshore structures in the present days, it is now realized that modeling the marine environment especially for exceptional environmental conditions is quite important. It is recognized that a possible improvement in the traditional modeling of environmental characteristics, which are the basis for the load models for structural analysis and design, may be needed. In this paper, the seasonal and directional varying properties in modeling the ocean parameter, the wave height, are studied. The peak over threshold（POT） method is selected to model the extreme wave height by utilizing a non-stationary discrete statistical extreme model. The varying parameters are taken into account with a changing pattern to reflect the seasonal and directional dependent behavior. Both the magnitude and the occurrence rate of the extreme values are investigated. Detailed discussion on the continuity of the established model is also given. The importance of the proposed model is demonstrated in reliability analysis for a jacket structure. The sensitivity to the changing marine environment in reliability analyses is investigated.

关键词： peak over threshold method climate change reliability analysis offshore structures point process extreme value distribution significant wave height