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Science china Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, LUO Xingzhang3, WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of Earth Sciences, state key laboratory of mineral deposit research, nanjing university, nanjing 210093. china 2. Center of Materials Analysis, nanjing university, nanjing 210093. china 3. Department of Environmental Science and Engineering, nanjing university, nanjing 210093. china 4. Beijing Geology Institute, Nuclear Industry, Beijing 100029, china Department of Earth Sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis nanjing university nanjing china Department of Environmental Science and Engineering nanjing university nanjing china Beijing Geology Institute Nuclear Industry Beijing china

The first results of sorption experiments of U(VI), 234U(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

A self-steering close-talking microphone array

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Progress in Natural Science:Materials International 2005年第11期15卷 1044-1049页

作者： PENG Ke, YANG Xinfeng and XU Boling (state key laboratory of Modern Acoustics, Institute of Acoustics, nanjing university, nanjing 210093. china) state key laboratory of Modern Acoustics Institute of Acoustics Nanjing University Nanjing 210093 China

For communication in extremely noisy environments, close-talking microphone arrays are useful. Differential microphone array systems possessing excellent nearfield directivity and strong farfield-noise reduction capability are very suitable for close-talking situations. In order to improve the focusing effect at the desired bearing in the nearfield, we propose a novel self-steering system of close-talking arrays with the first-order differential sub-arrays in this paper. Calculations of directivity patterns and directivity factors show that when a kind of optimized beamforming technique is adopted even small arrays with a focusing configuration will exhibit a satisfactory nearfield directivity which is electronically steerable within a specific range. The superiority of the proposed array system is verified by experiments with real acoustic data.

关键词： close-talking array differential array self-steering directivity factor.

Recent progress of solar physics research in china

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research in Astronomy and Astrophysics 2011年第12期11卷 1377-1402页

作者： Cheng Fang 1 School of Astronomy and Space Science,nanjing university,nanjing 210093.china 2 key laboratory of Modern Astronomy and Astrophysics(nanjing university),Ministry of Education,china School of Astronomy and Space Science Nanjing University Nanjing 210093 China key laboratory of Modern Astronomy and Astrophysics (nanjing university) Ministry of Education China

Owing to the largely improved facilities and working conditions, solar physics research in china has recently shown marked development. This paper reports on the recent progress of solar physics research in china's Mainland, mainly focusing on several hot issues, including instrumentations, magnetic field observations and research, solar flares, filaments and their eruptions, coronal mass ejections and related processes, as well as active regions and the corona, small-scale phenomena, solar activity and its predictions. A vision of the future is also described.

关键词： Sun: general -- Sun: coronal mass ejections (CMEs) -- solar physics:recent progress

Differential AR algorithm for packet delay prediction

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Progress in Natural Science:Materials International 2006年第4期16卷 437-440页

作者： JIAO Liangbao, ZHANG De and BI Houjie Institute of Acoustics, state key laboratory of Modern Acoustics, nanjing university, nanjing 210093. china Institute of Communication Technique, nanjing university, nanjing 210093. china [a]Institute of Acoustics State Key Laboratory of Modern Acoustics Nanjing University Nanjing China [b]Institute of Communication Technique Nanjing University Nanjing China

Different delay prediction algorithms have been applied in multimedia communication, among which linear prediction is attractive because of its low complexity. AR (auto regressive) algorithm is a traditional one with low computation cost, while NLMS (normalize least mean square) algorithm is more precise. In this paper, referring to ARIMA (auto regression integrated with moving averages) model, a differential AR algorithm (DIAR) is proposed based on the analyses of both AR and NLMS algorithms. The prediction precision of the new algorithm is about 5-10 db higher than that of the AR algorithm without increasing the computation complexity. Compared with NLMS algorithm, its precision slightly improves by 0.1 db on average, but the algorithm complexity reduces more than 90% . Our simulation and tests also demonstrate that this method improves the performance of the average end-to-end delay and packet loss ratio significantly.

关键词： AR algorithm NLMS algorithm differential AR algorithm ARIMA model.

Water in peridotite xenoliths from South china

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Science china Earth Sciences 2011年第10期54卷 1511-1522页

作者： WANG Rong 1,2,3 & ZHANG BaoMin 3 1 Faculty of Land Resource Engineering, Kunming university of Science and Technology, Kunming 650093, china 2 state key laboratory for mineral deposits research, nanjing university, nanjing 210093. china 3 Faculty of Earth Science, china university of Geosciences, Wuhan 430074, china 1. Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China2. State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing 210093 China3. Faculty of Earth Science China University of Geosciences Wuhan 430074 China

The water contents of nominally anhydrous clinopyroxene （cpx）, orthopyroxene （opx） and olivine （ol） in peridotite xenoliths hosted by Cenozoic basalts from Yingfengling, Zhangchouchun, Fujitian and Lindi, South china, were measured by Micro- FTIR. All cpx and opx grains contained a certain amount of water, which was indicated by the presence of hydroxyls in the crystal structure. The water contents （H20, ppm） of cpx and opx from peridotite xenoliths of the study areas were 293-981, 183-752, 73-586 and 51-423 ppm, and 82-471, 74-571, 53-170 and 9-135 ppm, respectively. No prominent OH absorption bands were detected for any ol grains, indicating that the water contents were below the detection limit （approximately 2 ppm）. The entire rock contents recalculated according to mineral volume proportions were 49-163, 48-168, 21-111 and 8-40 ppm, respectively. Combined with previously reported data describing the water contents of peridotite xenoliths worldwide, the results presented here suggest that water distribution in the continental lithospheric mantle is spatially heterogeneous at a global scale. The lithospheric mantle of South china is much richer in water than that of the North china Craton, and is close to that typical of off-craton localities, such as the Basin and Range Province, and Massif Central.

关键词： FTIR water peridotite xenoliths South china

Inclusion Behavior of Dimer β-CyclodextrinBridged with Aspartic Acid Derivative

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Chinese Chemical Letters 2001年第2期12卷 119-120页

作者： Le Xin SONG Coordination Chemistry Institute & state key laboratory of Coordination Chemistry, nanjing university, nanjing 210093 nanjing Univ Inst Coordinat Chem Nanjing 210093 Peoples R China nanjing Univ State Key Lab Coordinat Chem Nanjing 210093 Peoples R China

The (β-cyclodextrin (CD) dimer bridged with aspartic acid (ASP) derivative, FITC-ASP(NH-(-CD)2 (Host, FITC=fluorescein-4-isothiocyanate), was synthesized. Fluorescence polarization study showed that the novel host formed an inclusion compound, [FITC-ASP(NH-(-CD)2]ATA, for which Kd was determined to be 5.0×10-6 mol/L by Beacon 2000 Analyzer, when ATA (Guest) = Adm-Trp-Arg-Arg-NH2 (Adm = 1-adamantanecarboxylic acid, Trp = tryptophan, Arg = arginine), where Kd is the dissociation constant in aqueous solution at 298 K.

关键词： β-Cyclodextrin amino acid peptide inclusion compound fluorescence polarization.

An SANS Study of Decomposition Kinetics in Amorphous Cu_(12.5)Ni_(10)Zr_(41)Ti_(14)Be_(22.5)

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Journal of Materials Science & Technology 1998年第3期14卷 193-199页

作者： Junming LIU(National laboratory of Solid state Microstructures, nanjing university and Center for Advanced Studies in Scienceand Technology of Microstructures, nanjing 210093. china) National laboratory of Solid state Microstructures Nanjing University Center for Advanced Studies in Science and Technology of Microstructures Nanjing 210093 China

Phase decomposition in amorphous Cu12.5Ni10Zr411Ti14Be22.5 alloy as annealed in the super-cooled liquid range was studied by applying small angle neutron scattering (SANS). As annealed between 600 K and 700 K, the alloy was observed to decompose into two new amorphous phases,with the second phase precipitates embedded in the matrix of the first. Long time annealing of the alloy results in crystallization in addition to evolution of the decomposed *** kinetic diagram of the decomposition and crystallization for this alloy is given. The second phase precipitates have several nanometers in size and occupy a quite low volume fraction. The decomposition of the supercooled liquid in overall temperature range exhibits the features of spinodal reaction.

关键词： Be Zr SANS Ni Ti

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

Crystal structure and single crystal EPR of (NH_4)_2(15-crown-5)_3[Cu(mnt)_2] and (NH_4)_2(benzo-15-crown-5)_4[Cu(mnt)_2]·0.5H_2O

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Science china Chemistry 2007年第5期50卷 607-613页

作者： SUI YunXia1, WEN LiLi2, ZHANG Huan3 & MENG QingJin2 1 Center of Modern Analysis, nanjing university, nanjing 210093. china 2 state key laboratory of Coordination Chemistry, Coordination Chemistry Institute, nanjing university, nanjing 210093. china 3 Jiangnan Institute of Computing Technology, Wuxi 214083, china 1. Center of Modern Analysis Nanjing University Nanjing 210093 China 2. state key laboratory of Coordination Chemistry Coordination Chemistry Institute Nanjing University Nanjing 210093 China 3. Jiangnan Institute of Computing Technology Wuxi 214083 China

The X-ray crystal structures of (NH4)2(15-crown-5)3[Cu(mnt)2] (1) and(NH4)2(benzo-15-crown-5)4-[Cu(mnt)2] ident to 0.5H2O (2) were *** single crystals arecomposed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2]^(2-)*** triple-decker dication in complex 1 and a sandwich dimmer in complex 2 wereobserved.X-Band EPR studies on the single crystals of both complex 1 and complex 2 have been carriedout at room temperature,which revealed that complex 2 showed a perfect hyperfine structure of Cuwhereas that of complex 1 could not be *** principal values and direction cosines of theprincipal axes of the g and A tensors were computed by a least-squares fitting *** spindensity of Cu(ll) was estimated according to the principal values of the A tensors and compared wellwith the results calculated based on DFT method.

关键词： supramolecular cation, H-bonding interaction, EPR, g and A tensors, DFT

Phytotoxicity of four herbicides on Ceratophyllum demersum,Vallisneria natans and Elodea nuttallii

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Journal of Environmental Sciences 2009年第3期21卷 307-312页

作者： PAN Huiyun,LI Xiaolu,XU Xiaohua,GAO Shixiang state key laboratory of Pollution Control and Resource Reuse,School of the Environment,nanjing university,nanjing 210093.china. [a]state key laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China

The physiological effects of 4 herbicides （butachlor, quinclorac, bensulfuron-methyl and atrazine） on 3 submerged macrophytes （Ceratophyllum demersum, Vallisneria natans and Elodea nuttallii） were tested in laboratory. The variables of the relative growth rate and the photosynthetic pigment content showed that all of the tested herbicides affected the growth of the plants obviously, even at the lowest concentration （0.0001 mg/L）. Except for the C. demersum treated with quinclorac at 0.005 and 0.01 mg/L, the relative growth rates of the plants were inhibited significantly （p 〈 0.01）. Statistical analysis of chlorophyll a （Chl-a） contents was carded out with both the t-test and one-way ANOVA to determine the difference between the treatment and control. The results showed that Chl-a contents of the plants in all treatment groups were affected by herbicides significantly, except for the C. demersum treated with bensulfuron-methyl at 0.0005 mg/L. The decrease in Chl-a content was positively correlated to the dosage of the herbicides in most treatment groups. It was suggested that herbicides in water bodies might potentially affect the growth of aquatic macrophytes. Since the Chl-a content of submerged macrophytes responded to the stress of herbicides sensitively and directly, it could be used as a biomaker in environmental monitoring or in the ecological risk assessment of herbicide contamination.

关键词： phytotoxicity herbicides submerged macrophyte ecological risk assessment