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Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2.3,LI Aimin1,3,CAI Jianguo1,3,MENG Guanhua1,3 & ZHANG Quanxing1,3 1. State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,nanjing university,nanjing 2.0093,china 2. nanjing College of Chemical Technology,nanjing 2.0048,china 3. Jiangsu Engineering & Technology Research center for Organic Toxicant Control and Resource Reuse,nanjing 2.0038,china 1. State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. nanjing College of Chemical Technology Nanjing 210048 China 3. Jiangsu Engineering & Technology Research center for Organic Toxicant Control and Resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2.G, 50# and 38# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

Alkali-silica Reactivity of Different Aggregates from Mineral and Textural Characteristics

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Journal of Wuhan university of Technology(materials Science) 2008年第6期23卷 901-906页

作者：莫祥银 Analysis and Testing center & Jiangsu Key Laboratory of Biofunctional materials Nanjing Normal University

To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of china, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with X-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^＋, K^＋, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.

关键词： petrographic examination of aggregates study of thin sections x-ray diffraction analysis chemical analysis scanning electron microscopy

Establishing time-dependent model of deformation modulus caused by bedrock excavation rebound by inverse analysis method

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Science china(Technological Sciences) 2008年第S2期51卷 1-7页

作者： WU ZhongRu1,2.GU YanChang1,3,GU ChongShi1,2.GUO HaiQing1 & SU HuaiZhi1,2.1 Hohai university,nanjing 2.0098,{2. 2.National Engineering Research center of Water Resources Efficient Utilization and Engineering Safety,nanjing 2.0098,{2. 3 nanjing Hydraulic Research Institute,nanjing 2.002.,{2. 1. Hohai university Nanjing 210098 China 2. National Engineering Research center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China 3. nanjing Hydraulic Research Institute Nanjing 210029 China

Rock rebound relaxation deformation,or even rock burst,caused by the excavation of dam base and abutment or high rock slope affects their stability and results in the fall of mechanical properties of the *** an inverse analysis method was proposed in this paper to establish the time-dependent model of deformation modulus caused by excavation *** basic principle is based on the combination of observed data of the excavation rebound deformation of dam abutment or rock slope,and the calculated rebound deformation by FEM under ground stress at the corresponding time in the excavation *** norm of the residuals of observed data and calculated data are taken as the objective ***,the time-dependent model of bedrock deformation modulus can be *** method displays its significance in the design of excavation,construction and operation management of dam base and high slope.

关键词： dam base rebound deformation modulus inverse analysis method time-dependent model Xiaowan Hydropower Station

Origin and age of Mn deposits of the Nantuo Formation in the Sinian System

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Chinese Science Bulletin 1997年第24期42卷 2072-2075页

作者： YANG Jiedong, WANG Zongzhe, XUE Yaosong, SUN Weiguo, TAO Xiancong and ZHOU Chuanming1. center of Modern Analysis, nanjing university,{2., china 2. nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, nanjing 2.0008, china center of Modern Analysis Nanjing University Nanjing China nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

THE tillites in the Nantuo Formation of the Sinian System is considered contemporary with theVaranger ice age. The manganese deposits in the Nantuo Formation are most suitable to iso-topic dating and may record the precious information on paleo-ocean chemistry. However,there have heen different views and disputations about their origin and age for a long time. The Sinian System in the Yangtze region is divided into 3 formations from base to top:the Nantuo Formation, the Doushantuo Formation and the Dengying Formation. The

关键词： Neoproterozoie ice age Mn deposit isotopic age.

Seasonal variation of global stratosphere-troposphere mass exchange

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Progress in Natural Science:materials International 2007年第12期17卷 1466-1475页

作者： Guo Dong1,2. Lu Daren2.and Sun Zhaobo1(1. Institute of Atmospheric Sciences, nanjing university of Information Science and Technology, nanjing 2.0044,{2. 2. LAGEO, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002.,{2.) Institute of Atmospheric Sciences Nanjing University of Information Science and Technology Nanjing 210044 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

By Wei formula in pressure coordinate, the stratosphere-troposphere mass exchange (STME) is diagnosed globally for 44 years from 1958 to 2.01 using the European center for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets. Regions of mass flux into the stratosphere are found over Indonesia, bay of Bangladesh and the mid-west coast of South Africa. Compensating mass outflow from the stratosphere appears mainly over mid-latitudes near large-scale troughs. Upward and downward transport of mass at the middle and high latitudes accompany with each other. Mass flux into troposphere is stronger in autumn and winter than in spring and summer. Strong downward mass flux into the troposphere occurs in eastern Asia the whole year with nearly stable sites. Although the area of eastern Asia accounts for only 5.6% of that of the northern hemisphere (NH), its net mass exchange reaches 15.83% of that of the NH, which means that research on STME of eastern Asia is greatly important to that of the NH and even the global areas. Air across the tropopause enters more from stratosphere to troposphere than that from troposphere to stratosphere, which is possibly related with systematic bias of the assimilated datasets and with persistent rise of the tropopause height. Contributions of the mass exchange and the mass flux exchange in the NH and southern hemisphere (SH) on their latitudes increase from equator to pole, with larger contributions in the NH. Mass exchange and mass flux exchange per areas at high latitudes are larger than that at low latitudes, which means greater mass exchange efficiency at high latitudes.

关键词： stratosphere troposphere mass exchange seasonal variation.

Analysis of crack propagation in concrete structures with structural information entropy

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Science china(Technological Sciences) 2010年第7期53卷 1943-1948页

作者： BAO TengFei1’2. PENG Yan1’2. CONG PeiJiang1’2.& WANG JiaLin1’2.1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai university, nanjing 2.002.,{2. 2.National Engineering Research center ofWater Resources Efficient Utilization and Engineering Safety, Hohai university, nanjing 2.002.,{2. 1. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210024 China2. National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210024 China

The propagation of cracks in concrete structures causes energy dissipation and release, and also causes energy redistribution in the structures. Entropy can characterize the energy redistribution. To investigate the relation between the propagation of cracks and the entropy in concrete structures, cracked concrete structures are treated as dissipative structures. Structural information entropy is defined for concrete structures. A compact tension test is conducted. Meanwhile, numerical simulations are also carried out. Both the test and numerical simulation results show that the structural information entropy in the structures can characterize the propagation of cracks in concrete structures.

关键词： crack entropy concrete sun

中国政治经济学年度发展报告（2.2.）（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： center for Studies of Contemporary Political Economy,Research Institute for 2.st-Century Marxism,Nankai university·university of Chinese Academy of Social Science center for Teaching and Research on Capital,Renmin university of china National Institute of Socialist Political Economy with Chinese Characteristics,Renmin university of china 南开大学·中国社会科学院大学2.世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2.2.）》。自2.10年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2.2.年报告聚焦12.专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12.报告（下）篇刊登。2.2.年报告（下）选题如下：

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Game model of safety monitoring for arch dam deformation

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Science china(Technological Sciences) 2008年第S2期51卷 76-81页

作者： SU HuaiZhi1,2.WU ZhongRu1,2.GU YanChang1,2.HU Jiang1 & WEN ZhiPing3 1 College of Water Conservancy and Hydropower Engineering,Hohai university,nanjing 2.0098,{2. 2.National Engineering Research center of Water Resources Efficient Utilization and Engineering Safety,nanjing 2.0098,{2. 3 Department of Computer Engineering,nanjing Institute of Technology,nanjing 2.0013,{2. College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China National Engineering Research center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China Department of Computer Engineering Nanjing Institute of Technology Nanjing 210013 China

Arch dam deformation is comprehensively affected by water pressure,temperature,dam's structural behavior and material properties as well as other *** them the water pressure and temperature are external factors(source factors) that cause dam deformation,and dam's structural behavior and material properties are the internal factors of deformation(resistance factors).The dam deformation is the result of the mutual game playing between source factors and resistance ***,resistance factors of structure and materials that reflect resistance character of arch dam structure are introduced into the traditional model,where structure factor is embodied by the flexibility coefficient of dam body and the maximum dam height,and material property is embodied by the elastic modulus of *** the basis of analyzing the correlation between dam deformation and resistance factors,the game model of safety monitoring for arch dam deformation is put forward.

关键词： arch dam deformation monitoring model flexibility coefficient game theory

IR STUDY ON MONOMOLECULAR PARTICLE AGGLOMERATES OF POLYSTYRENE OBTAINED BY FREEZE-DRYING OF ITS DILUTE SOLUTION

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Chinese Journal of Polymer Science 2002年第4期20卷 381-383页

作者： Song Wang Qing-hua Wang Rong-shi Cheng Research center of materials Beijing Institute of Technology Beijing 100081,{2. Department of Chemistry nanjing university nanjing 2.0093,{2. nanjing Univ Dept Chem Nanjing 210093 Peoples R China Beijing Inst Technol Ctr Mat Res Beijing 100081 Peoples R China

The monomolecular particle agglomerates of polystyrenes were obtained by freeze-drying of its very dilute solutions of 1.3 x 10(-5)-2.0 x 10(-5) g/mL in benzene:cylcohexane (100:1) solvents, and they were annealed at room temperature for hundred days before use. According to C-13-NMR measurement the polystyrenes should be practically atactic. The number average molecular weights of the samples are 2.80 x 10(3), 2.00 x 10(4), and 1.55 x 10(6), respectively. The freeze-dried aPS with a molecular weight higher than 10(4) show two new IR absorption bands at 1098 and 12.1 cm(-1), which are absent in the normal aPS and freeze-dried styrene oligomer. It was also found that the low molecular weight samples can only form powders, whereas the freeze-dried aPS with higher molecular weight form a mixture of powders and fibrils, of which the longer fibrils show a much stronger 12.1 cm(-1) band than the shorter fibrils and the powder. It seems that the 12.1 cm(-1) band corresponds to the stacking behavior of monomolecular particles.

关键词： monomolecular particles atactic polystyrene FTIR spectroscopy