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On the evolution and histology of some Cambrian protoconodonts, paraconodonts and primitive euconodonts

Science China Earth Sciences 2004年第7期47卷 577-584页

作者： DONG Xiping Department of Geology, Peking university, Beijing 100871, China laboratory of Palaeobiology & Stratigraphy, nanjing Institute of Ge-ology and Palaeontology, Chinese Academy of Sciences,{3., China 1. Department of Geology Peking University 100871 Beijing China 2. laboratory of Palaeobiology & Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 210008 Nanjing China

Previous reports on the morphological evolution of protoconodonts and paraconodonts are reviewed. The evolutionary trends exhibited by species of the protoconodont genus Gapparodus and the paraconodont genus Westergaadodina are discussed. Based on the present study on histology, genus Paibiconus is protoconodont, while genus Yongshunella is paraconodont (fig. 1 (a)). However, the nature of Huayuanodontus has not been fully understood so far. Recently, the transitional form New Gen. Sensu Miller, 1980 of late Late Cambrian has been found in Hunan Province, South China. It is considered as the Sister-Group of Proconodontus. Moreover, another kind of transitional form of middle Late Cambrian and late Late Cambrian between Prooneotodus notundatus and Pnoconodontus, which looks like Prooneotodus notundatus in gross morphology, but has anterior and posterior costae, has also been found in Hunan, South China. This kind of transitional form is believed to be probably the real intermediate link between Prooneotodus rotundatus and Pnoconodontus, and Prooneotodus rotundatus is most probably the ancestor of Proconodontus. The two transitional forms noted above are all euconodonts by the study of their histology. Unlike the euconodonts of Post-Cambrian, the evolutionary relationships among the species of protoconodonts, paraconodonts and the primitive euconodonts could not be made clear without the histological study on them.

关键词： protoconodonts, paraconodonts, evolution, histology, Cambrian.

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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 {3. 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

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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 {3.,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

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The Interaction of Cobalt (Ⅲ) Mixed-Ligand Coordination Compound Containing Dipyrido[3.2-a:2′,3.-c] phenazine With Calf Thymus DNA -

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Chinese Chemical Letters 1997年第6期8卷 551-552页

作者： Lan JIN Pin YANG (state Key laboratory of Coordination Chemistry, nanjing university, {3. 210093. Institute of Molecular Science, Shanxi university. Taiyuan 03.006) state Key Lab. of Coord. Chemistry Nanjing University Nanjing 210093 China Institute of Molecular Science Shanxi University Taiyuan 030006 China

The binding of Co (phen)2dppz3. to calf thymus DNA,as investigated using absorption spectroscopy. viscosity and electrophoresis measurements,here dppz is dipyrido[3. 2-a: 2'3.-c]phenazine. The compound shows absorption hypochromicity and the specific viscosity increased upon binding to calf thymus DNA The complex is also shown to be more efficient photosensitisers for single strand breaks in plasmid DNA

关键词： phenazine With Calf Thymus DNA Figure Mixed-Ligand Coordination Compound Containing Dipyrido[3.2-a The Interaction of Cobalt

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Study on the reaction of triple helix poly(A:2I) with Cu^(2+)

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Chinese Journal of Chemistry 1996年第4期14卷 297-302页

作者： HUA, Er-BingCoordination Chemistry Institute, state Key laboratory of Coordination Chemistry, nanjing university, {3., Jiangsu 210008, ChinaYANG, Pin LI, Qing-Shan YANG, Bin-ShengInstitute of Molecular Science, Shanxi university, Taiyuan, Shanxi 03.006, China Coordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210008 China

The effect of Cu2+ on the triple-stranded helical structure of poly(A:2I) was studied by means of circular dichroism spectral method with the help of ultraviolet spectral and ethidium bromide fluorescence probe methods. It was found that Cu2+ destabilizes the structure of the triple helix poly(A:2I) and induces its structural transformations, meanwhile, the transformations can be partially reversed by a higher NaCl concentration. The structural transformations may be expressed by the following scheme: poly(A:2I) - poly(A:I) + poly(I)- poly(A) + 2poly(I)

关键词： Poly(A:2I) CD fluorescence probe structural transformation

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Exploiting remote learners in Internet environment with agents

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Science China(Information Sciences) 2010年第1期53卷 64-76页

作者： LI Ming, WANG Wei & ZHOU ZhiHua national Key laboratory for Novel Software Technology, nanjing university, {3. 210093. China 1. national Key laboratory for Novel Software Technology Nanjing University Nanjing 210093 China

Data in the Internet are scattered on different sites indeliberately, and accumulated and updated frequently but not synchronously. It is infeasible to collect all the data together to train a global learner for prediction; even exchanging learners trained on different sites is costly. In this paper, aggregative-learning is proposed. In this paradigm, every site maintains a local learner trained from its own data. Upon receiving a request for prediction, an aggregative-learner at a local site activates and sends out many mobile agents taking the request to potential remote learners. The prediction of the aggregative-learner is made by combining the local prediction and the responses brought back by the agents. Theoretical analysis and simulation experiments show the superiority of the proposed method.

关键词： machine learning data mining aggregative-learning mobile agent Internet environment

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EXPERIMENT OF IMPACT OF RIVER HYDRAULIC CHARACTERISTICS ON NUTRIENTS PURIFICATION COEFFICIENT

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Journal of Hydrodynamics 2007年第3期19卷 387-393页

作者： WANG Pei-fang WANG Xiao-rong WANG Chao state Key laboratory of Pollution Control and Resource Reuse School of Environment Nanjing University Nanjing 210093 China state Key laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Key laboratory of Intergrated Regulation and Resource Development on Shallow Lakes College of Environmental Science and Engineering Hohai University Nanjing 210098 China

Hydraulic characteristics of a river are the key factors for river water quality improvement and river restoration. A simulated river was exploited to study the interactions between water contaminant purification coefficients and the characteristics of the river, such as the cross-section velocity, water depth, Reynolds number, and Froude number. To enhance the purification capacity of the river, detritus with 5 mm to 10 mm in diameter and contact surface area per volume of 87.6 m^2/m^3.were constructed naturally at the bed and along one side of the bank to form half shape of the river cross-section. During the one-month experiment （including 3.periods） from the third of November to the fourth of December, 2005, three categories of hydraulic conditions were investigated. Results show that the purification coefficient （K） of Total Nitrogen （TN） is closely coherent with the hydraulic retention time （T）, river length （L）, Reynolds number （Re） and Froude number （Fr）. The relationship of K and T generally agrees with the power law under the three experimental water hydraulic conditions. Based on these results, the optimal Re and Fr ranges can be obtain to serve as a guideline for ecological re-engineering design to improve river water quality and restore river ecosystem.

关键词： Hydraulic characteristics total nitrogen,purification coefficient interaction simulated river

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Characteristics of Li diffusion on silicene and zigzag nanoribbon

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Chinese Physics B 2016年第1期25卷 742-745页

作者：郭艳华曹觉先徐波 College of Materials Science and Engineering Nanjing Tech UniversityNanjing 210009China Department of Physics Xiangtan UniversityXiangtan 411105China Department of Materials Science and Engineering and national laboratory of Solid state {3. Nanjing UniversityNanjing 210093China

We perform a density functional study on the adsorption and diffusion of Li atoms on silicene sheet and zigzag nanoribbons. Our results show that the diffusion energy barrier of Li adatoms on silicene sheet is 0.25 eV, which is much lower than on graphene and Si bulk. The diffusion barriers along the axis of zigzag silicene nanoribbon range from0. 1 to 0.25 eV due to an edge effect, while the diffusion energy barrier is about 0.5 eV for a Li adatom to enter into a silicene nanoribbon. Our calculations indicate that using silicene nanoribbons as anodes is favorable for a Li-ion battery.

关键词： Li diffusion silicene sheet silicene nanoribbons density functional theory

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PHOTOLUMINESCENCE OF TWO-PHASE COEXISTED NONSTOICHIOMETRIC BARIUM TITANATE BY LOW TEMPERATURE HYDROTHERMAL PROCESS

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南京大学学报(自然科学) 1999年第1期 131-133页

作者： Yu Jian Zhang Weifeng Chen Qiang Zhang Mingsheng ( Center for Materials Analysis and national laboratory of Solid state {3., nanjing university, 210093. nanjing, PRC)

ＳｔｒｕｃｔｕｒａｌｓｔｕｄｉｅｓｏｆＢａＴｉＯ３ｕｌｔｒａｆｉｎｅｐｏｗｄｅｒｈａｖｅｓｈｏｗｎｔｈａｔｐａｒｔｉｃｌｅｓｉｚｅｉｎｄｕｃｅｓｐｈａｓｅｔｒａｎｓｆｏｒｍｆｒｏｍｔｅｔｒａｇｏｎａｌｔｏｃｕｂｉｃａ... 详细信息

ＳｔｒｕｃｔｕｒａｌｓｔｕｄｉｅｓｏｆＢａＴｉＯ３ｕｌｔｒａｆｉｎｅｐｏｗｄｅｒｈａｖｅｓｈｏｗｎｔｈａｔｐａｒｔｉｃｌｅｓｉｚｅｉｎｄｕｃｅｓｐｈａｓｅｔｒａｎｓｆｏｒｍｆｒｏｍｔｅｔｒａｇｏｎａｌｔｏｃｕｂｉｃａｔｃｒｉｔｉｃａｌｖａｌｕｅ．［１...

关键词： photoluminescence two phase low temperature hydrothermal

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Optical applications of quantum dots in biological system

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Science China Chemistry 2011年第8期54卷 1177-1184页

作者： WANG Wei & ZHU Jun-Jie state Key laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering, nanjing university, {3. 210093. China 1. state Key laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

This review presents a simple introduction on the unique properties and general synthesis of quantum dots (QDs) in which we lay emphasis on the optical applications in the biological system. The detection of biological molecules such as DNA, protein and enzyme, the cell-based analysis and in vivo animal imaging are mainly discussed.

关键词： quantum dots optical application biological system

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