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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.{3. 2. nanjing College of Chemical Technology,nanjing 210048,{3. 3. Jiangsu Engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse,nanjing 21003.,{3. State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing China nanjing College of Chemical Technology Nanjing China Jiangsu Engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse Nanjing 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 HP2MG, 50# and 3.# 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.

Two possible mechanisms for vortex self-organization

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science china Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological sciences, Beijing 100081, china 2. department of Space Information science, nanjing University of Information science and Technology, nanjing 210044, china 3. Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china department of Environmental science Nanjing University of Information Science and Technology Nanjing China Chinese Academy of Meteorological sciences Beijing China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Preparation and Characterization of Nanocomposite MgFe_2O_4/SiO_2

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Journal of Wuhan University of Technology(Materials science) 2009年第3期24卷 354-358页

作者：徐莉 College of science Nanjing Forestry University

Nanocomposites MgFe2O4/SiO2 were successfully synthesized by the sol-gel method in the presence of N, N-dimethylformamide （DMF）. The formation of pure MgFe2O4 was confirmed by powder X-ray diffraction （XRD） and electron diffraction. The structural evolution of MgFe2O4 nanocrystals was followed by powder X-ray diffraction and IR absorption spectroscopy. The formation of spinel structure of MgFe2O4 started at 800 ℃, and completed at 900 ℃, The transmission electron microscopy （TEM） measurements suggest that the particle sizes increase with the increasing annealing temperature, and the mean particle sizes of the spherical samples annealed at 800 ℃, 900 ℃ and 1 050 ℃ are ca. 3.nm, 8 nm and 11 nm, respectively. Magnetization measurements at room temperature and 78 K indicate supemaramagnetic nature of these MgFe2O4 nanocrvstals.

关键词： nanocomposite sol-gel magnesium ferrite magnetic property

Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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science china Earth sciences 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2, JIANG Shaoyong1,2, WANG Xiaolei1,2, YANG Jinghong 1,2 & ZHANG Mengqun 3.1. State Key Laboratory of Mineral Deposit Research, nanjing University, nanjing 2.0093. china 2. department of Earth {3.s, nanjing University, nanjing 2.0093. china 3. Modern Analysis Center, nanjing University, nanjing 2.0093. china State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China department of Earth sciences Nanjing University Nanjing China Modern Analysis Center Nanjing University Nanjing China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2 contents in the range of 1.92%-3.21%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.24, which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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science china Earth sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2, MEI Bowen1 & CAO Yacheng3.1. Jianghan Petroleum University, Jingzhou 43.100, china 2. Huazhong University of science and Technology, Wuhan 43.047, china 3. {3. Institute of Soil science, Chinese Academy of sciences, {3. 210008, china Jianghan Petroleum University Jingzhou China Huazhong University of science and Technology Wuhan China nanjing Institute of Soil science Chinese Academy of Sciences Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15N is in the range of ?6‰-20‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15N with the value of about 1‰-5‰ whereas the oils in saline or semi-saline environment have higher δ 15N, with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

EPR studies of Mn^(2+) in the Loess Plateau of central china: Implication for variation of the East Asia summer monsoon

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Chinese science Bulletin 1998年第1期43卷 72-75页

作者： CHEN Jun\+1, JI Junfeng\+1, SU Yuanxia\+2 and LU Huayu\+3.. department of Earth sciences, nanjing University,{3. 2. Center of Material Analysis, nanjing University,{3. 3. Xi’an Laboratory of Loess and Qu department of Earth sciences Nanjing University Nanjing China Center of Material Analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Mn 2+ EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus Mn 2+ EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of Mn 2+

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second Institute of Oceanography, State Oceanic Administration, Hangzhou 3.0012, china 2 Center for Materials Analysis, nanjing University, nanjing 2.0093. china 3. {3. of Earth sciences, nanjing University, nanjing 2.0093. china Second Institute of Oceanography State Oceanic Administration Hangzhou China Centu for Materials Analysis Nanjing University Nanjing China department of Earth sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

Parabolic equation of the m-Laplacian with nonlinear boundary condition

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Chinese science Bulletin 1998年第11期43卷 905-908页

作者： WANG Shu+ 1, 2, WANG Mingxin 3. XIE Chunhong 1 1. department of Mathematics, nanjing University, nanjing 2.0093. china 2. department of Mathematics, Henan University, Kaifeng 475001, china 3. department of Applied Mathematics, Southeast University, department of Mathernntics Nanjing University Nanjing China department of Mathematics Henan University Kaifeng China department of Applied Mathematics Southeast University Nanjing China

The existence and nonexistence of global positive weak solutions of parabolic equation of the m-Laplician with nonlinear boundary condition are dealt with. The necessary and sufficient conditions on the existence of a... 详细信息

关键词： nonlinear boundary condition parabolic equation of m-Laplacian global solution blow-up.

社会化批注能否提升阅读理解水平？基于个体化和社会化批注对比的实验研究

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中国图书馆学报 2024年

作者：李武艾鹏亚姚琦 1.上海交通大学媒体与传播学院 2.南洋理工大学黄金辉传播与信息学院 3.华东师范大学心理与认知科学学院上海交通大学媒体与传播学院南洋理工大学黄金辉传播与信息学院华东师范大学心理与认知科学学院

社会化批注是用户开展社会化阅读的重要实践活动。借鉴计算机支持的协作学习框架和认知负荷理论，本研究采用实验法比较个体化和社会化批注对读者文本阅读理解水平的影响。实验结果显示，虽然社会化批注并未显著影响自我评估的阅读理解... 详细信息

社会化批注是用户开展社会化阅读的重要实践活动。借鉴计算机支持的协作学习框架和认知负荷理论，本研究采用实验法比较个体化和社会化批注对读者文本阅读理解水平的影响。实验结果显示，虽然社会化批注并未显著影响自我评估的阅读理解水平，但对专家打分的阅读理解水平产生了显著的正向影响。中介分析进一步表明，相对于个体化批注，社会化批注提高了读者的感知阅读支持，后者又提升了自我评估和专家打分的阅读理解水平；与个体化批注相比，社会化批注对读者的感知阅读干扰没有显著影响，而感知阅读干扰对通过两种测量方式获取的阅读理解水平也都没有显著的预测作用。理论层面，本研究有助于更加深入全面地洞察社会化批注对阅读理解水平的影响及其背后的作用机理。实践层面，研究结果对社会化阅读软件（尤其对其批注功能）的设计和完善具有重要的参考作用，也能启发阅读推广者思考如何引导读者利用社会化批注的积极作用提升对文本内容的理解和掌握。表5。参考文献52。

关键词：社会化阅读社会化批注个体化批注阅读理解计算机支持的协作学习框架认知负荷理论