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Nanopatterning of substrates by self-assembly in supramolecular block copolymer monolayer films

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Science China Chemistry 2013年第1期56卷 48-55页

作者： PEREPICHKA Iryna I. CHEN XiMin BAZUIN C. géraldine Département de Chimie Centre de Recherche sur les Matériaux Auto-assemblés (CRMAA/CSACS)Université de MontréalC.P.6128 Succ.Centre-villeMontréal (QC) H3C 3J7Canada

Many technological applications require templates with nanoscale *** copolymer self-assembly is a method of choice for obtaining a large variety of such patterns,with greatest flexibility achieved when combined with a supramolecular *** of the ways to fabricate block copolymer templates is the Langmuir-Blodgett (LB) ***,we briefly summarize recent work with LB films of polystyrene-poly(4-vinyl pyridine) (PS-P4VP) mixed with 3-n-pentade cylphenol (PDP),illustrating the different types of patterns possible and the principles governing *** interesting pattern that can be easily achieved with this system is the so-called "nanostrand network",which,when used as a template for gold deposition,can produce double striped lines of ***,we show how this pattern can be modified by acetone swelling to give rise to gold monolayer ribbons with internal *** results also suggest new insights into the early stages of morphology formation at the air/water interface.

关键词：嵌段共聚物单层薄膜超分子自组装衬底空气水界面乙烯基吡啶聚苯乙烯

Abatement of SO_2–NOx binary gas mixtures using a ferruginous active absorbent:Part I. Synergistic effects and mechanism

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Journal of Environmental Sciences 2015年第4期27卷 55-64页

作者： Yinghui Han Xiaolei Li Maohong Fan Armistead g.Russell Yi Zhao Chunmei Cao Ning Zhang genshan Jiang School of Mathematics and Physics North China Electric Power University School of Energy Resources and Department of Chemical & Petroleum Engineering University of Wyoming School of Civil and Environmental Engineering Georgia Institute of Technology Shanxi Electric Power Exploration & Design Institute China's State Energy Group Co.

A novel ferruginous active absorbent, prepared by fly ash, industrial lime and the additive Fe（VI）, was introduced for synchronous abatement of binary mixtures of SO2–NOx from simulated coal-fired flue gas. The synergistic action of various factors on the absorption of SO2 and NOx was investigated. The results show that a strong synergistic effect exists between Fe（VI） dose and reaction temperature for the desulfurization. It was observed that in the denitration process, the synergy of Fe（VI） dose and Ca/（S ＋ N） had the most significant impact on the removal of NO, followed by the synergy of Fe（VI） and reaction temperature, and then the synergy of reaction temperature and flue gas humidity. A scanning electron microscope（SEM） and an accessory X-ray energy spectrometer（EDS）were used to observe the surface characteristics of the raw and spent absorbent as well as fly ash. A reaction mechanism was proposed based on chemical analysis of sulfur and nitrogen species concentrations in the spent absorbent. The gibbs free energy, equilibrium constants and partial pressures of the SO2–NOx binary system were determined by thermodynamics.

关键词： Fe(VI) Desulfurization Denitration Binary gas Synergized effect Thermodynamics

短柱气相色谱法研究焚烧炉飞灰上萘的氯化反应及其产物

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环境化学 1992年第5期11卷 53-58页

作者：龙耀庭,陆妙琴,Hoffman R V,Eiceman g A 中国科学院生态环境研究中心中国科学院生态环境研究中心 Department of Chemistry New Mexico State University Las Cruces NM 88001-30001 USA Department of Chemistry New Mexico State University Las Cruces NM 88001-30001 USA 北京 100085 北京 100085

本文用0.3mBenton-34/OV-1短填充柱气相色谱法研究了萘在焚烧炉飞灰上的氯化反直产物,实验表明,飞灰表面性质对氯化有促进作用,这种促进作用与飞灰的来源或表面性质有强烈关系,文中对有关分析方法和萘在焚烧炉飞灰上氯化反应的结果作了... 详细信息

本文用0.3mBenton-34/OV-1短填充柱气相色谱法研究了萘在焚烧炉飞灰上的氯化反直产物,实验表明,飞灰表面性质对氯化有促进作用,这种促进作用与飞灰的来源或表面性质有强烈关系,文中对有关分析方法和萘在焚烧炉飞灰上氯化反应的结果作了讨论。

关键词：短柱气相色谱法荼氯荼氯化反应

Reinforcement of Hydroxypropylcellulose Films by Cellulose Nanocrystals in the Presence of Surfactants

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Chinese Journal of Polymer Science 2016年第11期34卷 1301-1301,1302-1310页

作者： Noor Rehman Maria Inez g.de Miranda Simone M.L.Rosa Clara I.D.Bica Instituto de Quimica Universidade Federal do Rio Grande do Sul 91501-970 Porto Alegre/RS Brazil Department of Chemistry Shaheed Benazir Bhutto University 18000 Sheringal Dir (Upper) KPK Pakistan Instituto de Ciencias Exatas e Tecnologicas Universidade FEEVALE Campus Ⅱ 93525-075 Novo Hamburgo/RS Brazil

Hydroxypropylcellulose（HPC） films were prepared by casting with cellulose nanocrystals in the presence of anionic surfactant sodium dodecylsulphate（SDS） and cationic surfactant hexadecyltrimethyl ammonium bromide（CTAB）. The cellulose nanocrystals were isolated from maize straw, a biomass source produced in huge quantities as an agrowaste in Brazil. These bionanocomposite films had good transparency and their surface hydrophilic character was evidenced by static contact angle measurements. Thermogravimetry（TgA） measurement revealed that nanocrystals and surfactants changed the thermal stability of the HPC films. Dynamic mechanical analysis（DMA） showed that the tensile storage and loss moduli of the HPC films increased by increasing the contents of cellulose nanocrystals and surfactants, especially in the case of CTAB. This good reinforcing effect of HPC matrix can be explained as due to electrostatic attractive interactions brought about by the presence of CTAB and the nanocrystals.

关键词： surfactant attractive hydrophilic cellulose reinforcing modulus cationic electrostatic tensile ammonium

Effect of initial microstructure on austenite formation kinetics in high-strength experimental microalloyed steels

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1304-1312页

作者： Edgar López-Martínez Octavio Vázquez-gómez Héctor Javier Vergara-Hernández Bernardo Campillo Faculty of Chemistry Metallurgical Engineering Department Autonomous National University of Mexico National Council for Science and Technology Metallurgy Science Postgraduate Programme Morelia Institute of Technology Institute of Physical Sciences Autonomous National University of Mexico

Austenite formation kinetics in two high-strength experimental microalloyed steels with different initial microstructures comprising bainite-martensite and ferrite-martensite/austenite microconstituents was studied during continuous heating by dilatometric analysis. Austenite formation occurred in two steps：（1） carbide dissolution and precipitation and （2） transformation of residual ferrite to austenite. Dilatometric analysis was used to determine the critical temperatures of austenite formation and continuous heating transformation diagrams for heating rates ranging from 0.03°C.s^-1 to 0.67°C.s^-1. The austenite volume fraction was fitted using the Johnson-Mehl-Avrami-Kolmogorov equation to determine the kinetic parameters k and n as functions of the heating rate. Both n and k parameters increased with increasing heat- ing rate, which suggests an increase in the nucleation and growth rates of austenite. The activation energy of austenite formation was determined by the Kissinger method. Two activation energies were associated with each of the two austenite formation steps. In the first step, the austenite growth rate was controlled by carbon diffusion from carbide dissolution and precipitation; in the second step, it was controlled by the dissolution of residual ferrite to austenite.

关键词： non-isothermal kinetics microalloyed steel austenite heating dilatometry

AZ31B镁合金的脉冲电流气体保护钨极焊过程参数优化(英文)

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Transactions of Nonferrous Metals Society of China 2011年第3期21卷 467-476页

作者： g.PADMANABAN V.BALASUBRAMANIAN Center for Materials Joining and Research (CEMAJOR) Department of Manufacturing Engineering Annamalai University

建立预测脉冲电流气体保护钨极焊AZ31B镁合金接头的拉伸强度经验方程。研究焊接过程参数如峰值电流、基础电流、脉冲频率和脉冲时间对焊接接头的影响。试验设计了一个四因素五水平的正交实验。建立的经验方程能够有效地预测脉冲电流钨... 详细信息

建立预测脉冲电流气体保护钨极焊AZ31B镁合金接头的拉伸强度经验方程。研究焊接过程参数如峰值电流、基础电流、脉冲频率和脉冲时间对焊接接头的影响。试验设计了一个四因素五水平的正交实验。建立的经验方程能够有效地预测脉冲电流钨电极惰性气体保护焊AZ31B镁合金的焊缝拉伸强度,可信度为95%。结果表明,脉冲频率对拉伸强度的影响最大,其次是峰值电流、脉冲时间和基电流。

关键词： AZ31B镁合金脉冲电流气体保护钨极焊响应面方法优化拉伸强度

Evolution of deformation twins with strain rate in a mediummanganese wear-resistant steel Fe-8Mn-1C-1.2Cr-0.2V

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Journal of Iron and Steel Research(International) 2019年第9期26卷 983-990页

作者： J. Chen J.J.Wang H.Zhang W.g.Zhang C.M.Liu Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819LiaoningChina School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Baosteel Special Steel Co. Ltd.Shanghai 200940China Northeastern Institute of Metal Materials Co. Ltd.Shenyang 110108LiaoningChina

Microstructure evolutions of the medium-manganese wear-resistant steel Fe-8Mn-1C-1.2Cr-0.2V (in wt.%) with stacking-fault energy of 22 mJ m-2 during deformation at strain rate ranging of 10^-2-1 s^-1 were analyzed by means of X-ray diffraction, field emission scanning electron microscopy and high-resolution transmission electron microscopy. The results indicate that the twinning-induced plasticity effect is the main strengthening mechanism of the studied steel, whilst the transformation-induced plasticity effect only occurs at high strain rate. With an increase in strain rate, volume fraction of the deformation twins, in particular that of the secondary twins, increases significantly along with decreasing average size. When applied strain rate is higher than 10^-1 s^-1, the parallel deformation twins are turned into a crossing morphology, and the original straight twin boundaries exhibit a ladder feature, which is attributed to the interactions between regular dislocations and twin dislocations at the twin boundary. The critical strain, a key indicator of the initiation of deformation twin, decreases with increasing strain rate. In addition, the ductility and strength of medium-manganese wear-resistant steel Fe-8Mn-1C-1.2Cr-0.2V are mainly determined by the shape and volume fraction of deformation twins.

关键词： Medium-manganese wear-resistant steel Stacking fault Twinning-induced plasticity effect Secondary twin Strain hardening rate

Tackling clinical complexity: how inpatient subspecialty gastroenterology services enhance patient care

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gastroenterology Report 2021年第6期9卷 606-607页

作者： Cinthana Kandasamy Darshan J.Kothari Sunil g.Sheth Department of Internal Medicine Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Division of gastroenterology Duke University Medical CenterDurhamNCUSA Division of gastroenterology Durham VA Medical CenterDurhamNCUSA Division of gastroenterology&Hepatology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA

Introduction Over the past three decades,the field of gastroenterology(gI)has undergone tremendous *** in research have led to a substantial growth in clinical knowledge across many gI ***,over this time,the prevalence of patient complexity,including the number of co-morbidities,mental illness burden,socioeconomic factors,and multidisciplinary needs,have continued to ***,subspecialization within gI has been an adaptive response to keep pace with the rapid expansion of medical knowledge and evolving patient needs.

关键词： patient clinical gastro

FACHB-COLLECTION:gENERAL INTRODUCTION AND THE STRAIN LIST

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水生生物学报 1999年第5期23卷 537-546页

作者： OngLirong S IuYongding L AnXiaoni g HuYunzhi Z UMinjuan Y Institute of Hydrobiology The Chinese Academy of Sciences Wuhan 430072

1 Introduction The Freshwater Algae Culture Collection of the Institute of Hydrobiology, abbreviation for FACHB-Collection, was initially established by the late Professor Li Shanghao, Professor Yu Minjuan and their colleagues in the early 1960’ s. At beginning the purpose of the culture collection was mainly to support the fundamental and applied researches in the Department of Phycology of the Institute of Hydrobiology . gradually, it developed as one of the main algal collections in China. The FACHB is open to distribute strains domestically and international-

关键词：水生生物学报