检索结果-南通市图书馆

Comparison of the Contributions of Tetrahydrofurfuryl Alcohol and PEG to a-Chymotrypsin Renaturation with High Performance Hydrophobic Interaction Chromatography

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2003年第3期14卷 294-297页

作者： Ye Hua SHEN Hai Bo WANG Quan BAI Xin Du geng 中国人民解放军85医院，上海200052

The contributions of tetrahydrofurfuryl alcohol (THFA) and polyethylene glycol (PEG) to the renatured efficiency of a-chymotrypsin were investigated and compared with each other. The maximum increments of bioactivity recovery of a-Chy were found to be 25.1% for THFA, 10.4% for PEG, respectively. The experimental results indicated that the denaturant solution containing THFA contributed more to the renaturation of a-Chy in high performance hydrophobic interaction chromatography (HPHIC) than that containing PEG, when the concentration of THFA was 3.2%, the bioactivity recovery of a-Chy is the highest.

关键词： High-perforamnce hydrophobic interaction chromatography tetrahydrofurfuryl alcohol (THFA) polyethylene glycol (PEG) protein renaturation a-chymotrypsin.

Soil Properties and Yield of Jerusalem Artichoke(Helianthus tuberosus L.)with Seawater Irrigation in North China Plain

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2008年第2期18卷 195-202页

作者： ZHAO geng-Mao liU Zhao-Pu CHEN Ming-Da GUO Shi-Wei College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）

Irrigation with various dilutions of seawater can act as an alternate water resource and thus plays an important role in saving freshwater resources as well as promoting agriculture in the coastal semi-arid areas of the North China Plain. Jerusalem artichoke （Helianthus tuberosus L.） grown in a field experiment was irrigated with seawater diluted with freshwater from 2001 to 2003 to determine the feasibility of seawater irrigation in the Laizhou area. For treatments of CK （non-irrigation） along with seawater concentrations of 25%, 50%, and 75%, total dissolved solid （TDS） in the non-irrigated soil significantly increased （P ≤ 0.05） in both 2002 and 2003 and was 1.3 times higher in 2003 than in 2001. In the 25% and 50% seawater concentration treatments, TDS in 2001 was significantly greater （P ≤ 0.05） than CK; however, TDS in these two treatments decreased by 34.9% and 40.1%, respectively, in 2003 compared with 2001. The sodium adsorption ratio （SAR） remained below 10 mmol^1/2 L^-1/2, indicating that alkalization was low with seawater irrigation. In 2001 and 2002, compared to CK and the irrigation treatment with 75% seawater, irrigation with 25% and 50% seawater increased the yields of Jerusalem .artichoke. This meant that Jerusalem artichoke could be safely grown in salt-affected land of Laizhou area with 25% and 50% seawater irrigation.

关键词： Jerusalem artichoke North China Plain SAR seawater irrigation soil total dissolved solids

A time-optimal aircraft-following model based on Pontryagin's minimum principle

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Transportation 2011年第4期19卷 268-273页

作者： linghang MENG Xiaohao XU Zengxian geng College of Air Traffic Management Civil Aviation University of China Tianjin 300300 China Air Traffic Management Research Base Civil Aviation University of China Tianjin 300300 China

A time-optimal aircraft-following model is introduced to address air traffic flow interference by velocity reduction. The objective function is set up as minimizing the recovery time during which the separation minima are not infringed and the separation of the air traffic flow returns to the initial separation at the terminal time. Pontryagin＇s minimum principle is used to solve the optimum aircraft-following velocity control law. An analytical minimum safe following separation is also provided under the time-optimal control law. The simulation results show that the precision first-order tracking accuracy is achieved without losing the separation.

关键词： air traffic flow aircraft-following model time-optimal control safe following separation

Study on an Adaptive Algorithm for Time-varying System

在线全文

学校读者我要写书评

暂无评论

Study on an Adaptive Algorithm for Time-varying System

Effects of the number of imidazoline ring and the length of alkyl group chain of imidazoline derivatives on corrosion inhibition of carbon steel in HCl solution:Molecular simulation and experimental validation

第36届中国控制会议

作者： KIM KwangHo geng Yanfeng Yue Yaobin College of Information & Control Engineering China University of Petroleum(East China) Automation Engineering Faculty Kimchaek University of TechnologyCAS College of Automation & Electronic Engineering Qingdao University of Science & Technology

ISBN: (数字)9789881563934

ISBN: (纸本)9781538629185

In this paper,we presented the derivation of an adaptive algorithm for time-varying system and verified that it satisfied convergence *** on the concept of distance in parameter space,we proposed a robust identification method which identified the smallest set of discrete transfer functions under the assumption that its parameters were time-varying and described derivation of an adaptive law based on verification and update algorithm of the identified model *** also described that the proposed algorithm satisfied the convergence properties through numerical simulation.

关键词： adaptive algorithm time-varying system parameter estimation robust identification

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Petroleum 2022年第4期8卷 447-457页

作者： Chenfeng Zhang Junying Hu Zhi Yang Ziqi Zheng Shuai geng Xiankang Zhong School of Oil and Natural Gas Engineering Southwest Petroleum UniversityChengdu610500China School of Materials Science and Engineering Xihua UniversityChengdu610039China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China

The effects of the number of imidazoline ring and the length of alkyl group chain of imidazoline derivatives were investigated using quantum chemical calculation,molecular dynamics simulation and experimental *** corrosion inhibitors including symmetrical lauric acid imidazoline(SAI),tetracyclic lauric acid imidazoline(LAI),and symmetric stearic acid imidazoline(SPI)were synthesized and their inhibition performance was evaluated using weight loss measurement,electrochemical techniques and surface *** results show that SAI and LAI with the same length of alkyl group chain,LAI with more imidazoline rings could supply a better inhibition performance since the increase of active *** increase of active sites attached to the metal surface may also change the distribution of corrosion inhibitor,which could limit inhibition performance ***,SAI and SPI with the same number of imidazoline rings,SPI with longer alkyl group chain shows a better inhibition efficiency due to the better hydrophobic performance of alkyl *** the three inhibitors,SPI shows the best inhibition performance,indicating that the alkyl group chain length affects the inhibition performance more obvious than the number of the imidazoline rings.

关键词： Imidazoline derivatives Corrosion inhibition Imidazoline ring Alkyl group chain

Thermoelastic Structural Topology Optimization Based on Moving Morphable Components Framework

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2021年第9期128卷 1179-1196页

作者： Jun Yan Qi Xu Zhirui Fan Zunyi Duan hongze Du Dongling geng Department of EngineeringMechanics StateKey Laboratory of StructuralAnalysis for Industrial EquipmentInternational Research Center for Computational MechanicsDalian University of TechnologyDalian116024China Institute of Structural Health Monitoring and Control School of MechanicsCivil Engineering&ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Ningbo Research Institute of Dalian University of Technology Ningbo315016China

This study investigates structural topology optimization of thermoelastic structures considering two kinds of objectives ofminimumstructural compliance and elastic strain energy with a specified available volume *** explicitly express the configuration evolution in the structural topology optimization under combination of mechanical and thermal load conditions,the moving morphable components(MMC)framework is *** on the characteristics of the MMC framework,the number of design variables can be reduced *** optimization formulation in the MMC topology optimization framework and numerical solution procedures are developed for several numerical *** optimization results are obtained with structural compliance and elastic strain energy as objectives,respectively,for thermoelastic *** effectiveness of the proposed optimization formulation is validated by the numerical *** is revealed that for the optimization design of the thermoelastic structural strength,the objective function with the minimum structural strain energy can achieve a better performance than that from structural compliance design.

关键词： Thermoelastic structure topology optimization moving morphable components minimum structural compliance minimum strain energy

“栅片房”的营造:南美拉祜族传统民居及其营造技艺研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

建筑学报 2021年第S1期 18-23页

作者：李玥耿虹任绍斌华中科技大学建筑与城市规划学院武汉430074

从"栅片房"营造视角出发,充分挖掘栅片房在其特殊时代背景、时间断面下的原真性和独特性的形式语汇,完整还原其整个营造过程及其特殊的技术文化内涵,以期为后期实现南美栅片房原真、活态的保护提供技术支持,同时为研究人类早期营建文化... 详细信息

从"栅片房"营造视角出发,充分挖掘栅片房在其特殊时代背景、时间断面下的原真性和独特性的形式语汇,完整还原其整个营造过程及其特殊的技术文化内涵,以期为后期实现南美栅片房原真、活态的保护提供技术支持,同时为研究人类早期营建文化提供原真性的可视素材。

关键词：南美拉祜族传统民居栅片房原真性低技营造技艺

中小城市传统商业街区活化振兴营造策略研究——基于日本高松丸龟町商店街的经验启示

在线全文

学校读者我要写书评

暂无评论

国际城市规划 2022年第1期37卷 124-133页

作者：耿虹李彦群乔晶华中科技大学建筑与城市规划学院城市规划系中华人民共和国自然资源部华中科技大学建筑与城市规划学院

自1990年以来,日本高松丸龟町商店街开展了为期近30年的振兴营造,通过采用民间主导、共同设计、以人为本等营造理念实施紧凑型商业空间整治,以及强化其公共物品属性的城市设施更新,推动商业街治理主体与商业模式的转型升级,成功实现了... 详细信息

自1990年以来,日本高松丸龟町商店街开展了为期近30年的振兴营造,通过采用民间主导、共同设计、以人为本等营造理念实施紧凑型商业空间整治,以及强化其公共物品属性的城市设施更新,推动商业街治理主体与商业模式的转型升级,成功实现了商业街区的活化更新营造。其先行经验为我国中小城市传统商业街区的活化营造提供了一定借鉴。文章基于对高松丸龟町商店街振兴案例的深度剖析,结合对我国中小城市传统商业街区本土衰退特征与更新困境的讨论,提出适合我国相应商业街区的活性化营造策略,包括社会成员主导的自主共同开发,规划控制指标的弹性管控,政府财政引导下的社会资本投放,集约化导向下的土地与空间治理,以及走向"以人为本"的城市公共物品营造。

关键词：商业街区紧凑空间活性化营造街区振兴以人为本公共物品高松丸龟町商店街

Assessment of water level threshold for groundwater restoration and over-exploitation remediation the Beijing-Tianjin-Hebei Plain

在线全文

学校读者我要写书评

暂无评论

Journal of Groundwater Science and Engineering 2022年第2期10卷 113-127页

作者： Hui-feng Yang Rui-fang Meng Xi-lin Bao Wen-geng Cao Ze-yan li Bu-yun Xu Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China National Field Scientific Observation and Research Station on Groundwater and Ground Subsidence in the Plain Area of Cangzhou Hebei 050061China

The Beijing-Tianjin-Hebei Plain(BTHP)is the political,economic and cultural center of China,where groundwater is the main source of water supply to support social and economic *** overdraft of the resources has caused a persistent decline of groundwater level and formed a huge cone of depression at a regional *** paper addresses current groundwater situation over the BTHP *** paper also delineates the groundwater flow field,using groundwater level data,in order to provide an effective method for the restoration of groundwater level and associated water resources *** on the analysis of multiple factors,such as groundwater level,soil salinization,ground subsidence,groundwater recharge and storage,urban underground space security,formation of fractures,and seawater intrusion,the threshold for groundwater level restoration is defined,and some measures for groundwater over-exploitation management are accordingly *** study shows that:(i)Since the 1980s to 2020,shallow groundwater level in the western part of the BTHP area has dropped by 25 m to 60m,while the cumulative decline of deep groundwater in the central and eastern regions is in the range of 40–80 m;(ii)The water table of the shallow groundwater within the depression zone over the Western Piedmont Plain should be controlled in the range of 15–30 m below ground level(mbgl),while the depth of groundwater level in large and medium-sized urban areas should be controlled within 20–30 *** groundwater level in the resource preservation area should be controlled within 10–15 mbgl,and the groundwater level in the area with identified soil salinization in the central and eastern plain should be controlled within 3–10 ***,for the deep groundwater in the central and eastern plainwater,the main focus of the resources management is to control the land *** water level in the severe land subsidence area should be controlled within 45–60 mbgl,and in the

关键词： Beijing-Tianjin-Hebei Plain Groundwater over-exploitation Groundwater level restoration threshold Groundwater reserve Over-exploitation control