检索结果-南通市图书馆

Covering α-Fe2O3 protection layer on the surface of p-Si micropillar array for enhanced photoelectrochemical performance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2017年第6期11卷 119-127页

作者： Jing gu Hongtao Yu Xie quan Shuo Chen Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) School of Environmental Science and Technology Dalian University of Technology Dalian 116024 China

The spontaneous oxidation process of pristine silicon （Si） limits its application as photocatalyst or electrode in aqueous solution or moist air. Covering a protection layer on Si surface is an effective approach to overcome this disadvantage. In this paper, α-Fe2O3 is demonstrated to be an excellent alternative as a protection material, α-Fe2O3 layer was deposited around each p-type Si micropillar （SiMP） in well-ordered array by chemical bath ＂deposition ＂method. The diameter of SiMP was 3 μm and the thickness of α-Fe2O3 layer was about 20 nm. The photoeletrochemical stability of SiMP/α-Fe2O3 was proved by 10 circles cyclic voltammetr7 testing. Compared with SiMP, its optical absorption and photocurrent density improved 2 times and 4 times, respectively, and its onset potential for hydrogen evolution moved positively about 0.4 V. These improved performances could be ascribed to the enhanced photogenemted-charge-separation efficiency deriving from built-in electric field at the interface between Si and α-Fe2O3. The above results show an effective strategy to utilize Si material as photocatalyst or electrode in aqueous solution or moist air.

关键词： Si α-Fe2O3 Photoelectrochemistry Photogenemted charge separation

Synthesis and ion exchange properties for Cs^+ of ammonium-type mordenite

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2015年第10期34卷 752-756页

作者： Dian-quan Dong Jian-guo Zheng Xian-lian Han College of Chemical Engineering School of Qingdao University of Science and Technology

Cesium content in the seawater is 3.0 9 10-4 mg·L-1, and ammonium-type mordenite was used to exchange cesium from cesium source. K-type mordenite was obtained by hydrothermal synthesis method. After ammonium-modified, ion exchange properties such as saturated ion exchange capacities and selectivity coefficients for alkali metal ions were determined. At the same time, ion exchange isothermal curves of ammonium-type mordenite for Cs+ and NH4+ were determined at 25°*** electrolyte solution theory was used to work out activity coefficients of the system, and the Kielland diagram of the ion exchange system was obtained. The calculated equilibrium constant(Ka) and ion free enthalpy(DG0) of mordenite for Cs+ and NH4+ are 1.455 and -930.3J·mol-1, respectively, indicating that ion exchange process of ammonium-type mordenite for cesium is a spontaneous process.

关键词： Ion exchange Thermodynamics Mordenite Cesium

In-situ SEM Observation of Monotonic and Cyclic Deformed Structure in Ti-2A1-2.5Zr Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第1期17卷 37-38页

作者： Zhentao YU lian ZHOU Haichen gu Ju DENG Northwest institute for Nonferrous Metal Research P.O.Box 51Xi’an 710016China Materials Science and Engineering College Xi’an Jiaotong UniversityXi’an 710049China

The SEM observation in situ of monotonic and cyclic deformed structure in Ti-ZA1-2.5Zr alloy was performed. The regularity of slippage, crack nucleation, propagation and the typical dislocation configuration were also investigated. The twin and twist play an important role in maintaining homogeneous deformation in the final plastic deformation stage.

关键词： plastic deformation in situ

从基于模拟到基于人工智能的建筑结构设计方法研究进展

在线全文

学校读者我要写书评

暂无评论

工程力学 2025年第3期42卷 1-17页

作者：陆新征廖文杰顾栋炼许镇郑哲清华大学土木工程系土木工程安全与耐久教育部重点实验室北京100084 北京科技大学土木与资源工程学院城镇化与城市安全研究院北京100083

建筑结构设计随着计算机技术进步迈入新的发展阶段,基于模拟与基于人工智能的设计为两个重要发展方向。基于模拟的设计为超出设计规范的特殊结构或特殊工况设计提供了关键手段,其关键难题是发展可以准确、高效模拟结构在地震、火、风等... 详细信息

建筑结构设计随着计算机技术进步迈入新的发展阶段,基于模拟与基于人工智能的设计为两个重要发展方向。基于模拟的设计为超出设计规范的特殊结构或特殊工况设计提供了关键手段,其关键难题是发展可以准确、高效模拟结构在地震、火、风等灾害作用下受力行为的模拟方法。基于人工智能的设计则是通过学习既有设计案例,从而高效生成满足工程经验和设计规范要求的结构设计图,可以有效提升结构设计效率,其关键难题在于对工程经验和结构特征的学习和表达。该文介绍了作者团队开展的基于模拟的抗震、防火、抗风设计的典型案例,以及基于生成对抗网络和图神经网络的人工智能结构设计方法,提出了L0~L5不同层级结构智能设计的划分建议,并展望了未来将基于模拟的设计和基于人工智能的设计相融合的发展方向。

关键词：建筑结构设计结构模拟方法基于模拟的设计生成式网络模型结构智能设计

Preface: Advances in OpenSees Applications to Civil Engineering

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2019年第9期120卷 467-470页

作者： Joel Conte Frank McKenna quan gu Department of Structural Engineering University of California at San DiegoLa JollaCA 92093USA NHERI SimCenter University of CaliforniaBerkeleyRichmond Field StationRichmondCA 94804USA School of Architecture and Civil Engineering Xiamen UniversityXiamenChina.

This special issue is dedicated to the memory of a world-renowned expert in earthquake engineering,Professor Stephen ***(October 16,1946-February 10,2018),for his educational efforts and visionary research contributions that spanned theory,numerical modeling,computer simulation,laboratory experiments,field testing,and design code *** decades of prolific,enthusiastic,and selfless service to the academia,profession and industry as well as his friendship will be remembered *** his capacity as the Director of the Pacific Earthquake Engineering Research(PEER)Center(2009-2015),Professor Mahin was steadfast in supporting the development and application of OpenSees(i.e.,Open System for Earthquake Engineering Simulation).To recognize his great efforts,this special issue is about the applications of OpenSees in civil engineering,and Computer Modeling in Engineering&Sciences(CMES)is a suitable journal for this special issue.

关键词： earthquake Director supporting

Preparation of Hydrophilic UHMWPE Hollow Fiber Membranes by Chemically Bounding Silica Nanoparticles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2021年第2期39卷 189-200,I0006页

作者： lian-lian Fan Jia-You quan Hao Zhang Jun-Rong Yu Zu-Ming Hu Yan Wang Shanghai Collaborative Innovation Center for High Performance Fiber Composites College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Sinochem International Corporation Shanghai 200126China

In this work, ultra-high molecular weight polyethylene (UHMWPE) microfiltration hollow fiber membranes prepared via the thermally induced phase separation (TIPS) method were modified by chemically bounding hydrophilic silica (SiO2) nanoparticles onto the surface to improve anti-fouling performance. A range of testing techniques including attenuated total reflection Flourier transformed infrared spectroscopy(ATR-FTIR), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), water contact angle, mechanical test,filtration and anti-fouling performance were carried out to discuss the influence of different modification conditions on the properties of the membranes. The prepared hollow fiber membranes display the significantly excellent performance when the vinyl trimethoxy silane (VTMS) concentration was 13%, the pH value of the hydrolyzate was 4 and the hydrolysis reaction time was 6 h. In particular, the hydrophilicity of modified membranes was improved effectively, resulting in the enhancement of membrane anti-fouling properties. The results of this work can be consulted for improving the anti-fouling performance of the UHMWPE microfiltration hollow fiber membrane applied in the field of water purification.

关键词： Hollow fiber membrane Hydrophilic Anti-fouling Silica(SiO2)nanoparticles Water purification

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2008年第14期53卷 2230-2238页

作者： lian JiJian WANG JiMin gu JinDe School of Civil Engineering Tianjin University Tianjin 300072 China

Similarity law is the conversion rule between model and prototype, on which a lot of research works have been done, with no agreement reached referring to the similarity law of fluctuating pressure fre- quency spectrum. Experimental data of peak frequency and dominant frequency range of fluctuating pressure spectrum beneath hydraulic jump obtained from serial models of scales 1:1, 1:2 and 1:5 are compared. As a result, similarity law of fluctuating pressure spectrum in the strongly rolling area agrees with the gravity law. As peak frequency and dominant frequencies of fluctuating pressures in hydraulic jump, toe and tail are rather low, and the similarity is often misunderstood to be λf = 1. However, the normalized spectrums of fluctuating pressures show that the similarity nearly agrees with the gravity law.

关键词：水跃脉冲压力相似性水资源利用

Expression and significance of MMP-7,c-Jun and c-Fos in rats skin photoaging

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2013年第10期6卷 768-770页

作者： Long-quan Shi Cai-lian Ruan Department of Dermatology Affiliated Hospital of Yan'an University

Objective:To investigate the expression and significance of the MMP-7,c-Jun and c-Fos in rat photoaging ***:A total of 45 SD rats were randomly divided into control group,model group,natural recovery group,physiological saline injection group and dermal pluripotent stem cells transplantation(DMSCs group),model group,natural recovery group,physiological saline injection *** were treated with UV lamp irradiation to establish light aging skin *** were then sacrificed after model prepared,no treatment was processed in the natural recovery *** injections was adopted in saline group,DESCs group was treated with DESCs *** were sacrificed after 4 *** expression of MMP-7,c-Jun and c-Kos were detected using the immunohistocheniical ***:In model group,MMP 7positive expression was higher than that in the other 4 groups,but without statistically difference(P>0.05);c-Jun,c-Fos expression were higher than that in the control group and DESCs group(P0.05).Conclusions:MMP-7,c-Jun and c-Fos can be used as diagnosis indicators in the early stage of light aging,and they jointly participate in its *** transplants is effective in treating light aging skin.

关键词： MMP-7 c-Jun c-Fos Aging skin Expression

Recognition of hairpin DNA from coil DNA by electrospray mass spectrometry with annealing strategy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2012年第4期23卷 500-503页

作者： Bo Zheng Yi quan Liu gu Yuan Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationDepartment of Chemical BiologyCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100086China Shanghai Research Institute of Chemical Industry Shanghai 200062China

This research presented an annealing strategy to identify hairpin DNA from coil DNA with the same base composition but different arrangements using electrospray mass spectrometry（ESI-MS）.A series of single-stranded DNA were annealed with their complementary sequences,*** the five pairs of hairpin DNA and coil DNA were unambiguously distinguished by ESIMS with annealing *** research offers a potential method to probe the DNA structure by comparing with mass spectral characteristics.

关键词： Hairpin DNA Annealing Mass spectrometry