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The First-principles Study on the Rectification of Molecular Junctions Based on the Alkyl-chain-modified[2,5?]Bipyrimidinyl(biphenyl isocyanide)gold(Ⅰ)

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Chinese Journal of Structural Chemistry 2020年第10期39卷 1763-1769,1741页

作者： GAO Quan-Dang yang e College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Using density functional theory(DFT)combined with nonequilibrium Green?s function investigates the electron-transport properties of several molecular junctions based on the[2,5?]bipyrimidinyl(biphenyl isocyanide)gold(Ⅰ)molecule(BPM-Au(Ⅰ)CN-BP),which is modified by one to three alkyl groups forming BPM-Au(Ⅰ)CN-BP(CH2)*** asymmetric current-voltage characteristics have been obtained for the molecular *** performance of Au/S-BPM-Au(I)CN-BP-S/Au molecular junction can be regulated by introducing alkyl *** M1 molecular junction exhibits the best rectifying *** maximum rectifying ratio is 2109,which is about 150 times more than that of the molecular junction based on the original ***,all the systems modified by alkyl group have obvious negative differential resistance behavior(NDR).The current-voltage(Ⅰ-Ⅴ)curves of all the systems in this work are illustrated by transmission spectra.

关键词： the first-principles isocyanide gold(Ⅰ)compound alkyl chain rectifying ratio

A Corrugated 2D Mn(Ⅱ) Network:[Mn_3(μ-oxalate)_3(μ-4,4'-bpy)_2(4,4'-bpy)_2]_n

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Chinese Journal of Structural Chemistry 2006年第7期25卷 873-877页

作者： yang e WANG Xiao-Qin CHeN Shun-Yu College of Chemistry ＆ Materials Science Fujian Normal University Fuzhou 350007 China Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The title complex, [Mn3（μ-oxalate）3（μ-4,4′-bpy）2（4,4′-bpy）2]n, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in the monoclinic, space group P2 1/c with a = 16.3222（6）, b = 16.2594（5）, c = 16.4885（5） A, β = 94.9900（10）°, V= 4359.3（2） A^3, Z = 4, Mn3C46N8O12H32, Mr = 1053.62, Dc = 1.605 g/cm^3, F（000） = 2140 and μ（MoKa） = 0.932 mm^-1. The structure was refined to R = 0.0578 and wR = 0.1061 for 4795 observed reflections （I 〉 2σ（I））. The oxalate anions behave as the bridging ligand and link two manganese atoms repeatedly to form infinite one-dimensional chains which further extend into a two-dimensional network by bridging 4,4′-bpy ligands.

关键词： crystal structure one-dimensional chain two-dimensional layer bridging 4,4′-bpy ligands terminal 4,4′-bp)- ligands

A Novel 3D Supramolecular Network Constructed from [Cu(4,4'-bipyridine)(O_2CMe)_2]_2 Molecular Ladders by Hydrogen Bonding

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1365-1368页

作者： yang e WANG Xiao-Qin QIN Ye-Yan College of Chemistry ＆ Materials Science Fujian Normal University Fuzhou 350007 China Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou 350002 China

The title complex, {[Cu2（4,4＇-bipyridine）2（μ-O2CMe）2（O2CMe）2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474（5）, b = 11.7566（2）, c = 19.5380（6）A, β = 92.930（2）°, V = 3084.84（16） A^3, Z = 4, Cu2C28N409H30, Mr = 693.64, Dc = 1.494 g/cm^3, F（000） = 1424 and μ（MoKα） = 1.436 mm^-1. With the use of 2062 observed reflections （I 〉 2σ（I））, the structure was refined to R = 0.0769 and wR = 0.2154. In complex 1, the dimeric copper acetate units are linked through 4,4’-bipyridine to yield ID molecular ladders. These ladders are connected via O-H…O hydrogen bonds to generate 2D layers, which are further linked through C-H…O hydrogen bonds to give a 3D supramolecular network.

关键词： molecular ladder dimeric copper acetate 3D supramolecular network

Geophysical evidence for thrusting of crustal materials from orogenic belts over both sides of the yangtze Block and its geological significance

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Science China earth Sciences 2019年第5期62卷 812-831页

作者： Yingkang LI Jianwei GAO Jian HAN Yu'e yang Geological Cores and Samples Center of Land and Resources CGS Institute of Geomechanics Chinese Academy of Geological Sciences Sinopec Geophysical Company Limited North China Branch

Based on deep geophysical detections, we have reconstructed the crustal structure from the eastern margin of the Tibetan Plateau to the Jiangnan-Xuefeng orogenic belt. The results suggest that the yangtze Block was overthrusted by crustal materials in its NW direction from the eastern Tibetan Plateau but in its Se direction from the Jiangnan orogen. These overthrusting effects control the crustal structure from the western Sichuan to the western area of the Jiangnan orogen-Xuefeng orogenic belt. The eastward extruded materials from the eastern Tibetan Plateau were blocked by the rigid basement in the Sichuan Basin, where upper-middle crust was overthrusted whereas the lower crust was underthrusted beneath the Sichuan Basin. The underthrusted unit was absorbed by crustal folding, shortening and thickening in the yangtze Block, forming the Xiongpo and Longquan Mountains tectonic belts and resulting in the NW-directed thrusting of the Pujiang-Chengdu-Deyang fault, and the western hillsiden fault in the Longquan Mountain. These results provide resolution to the controversy where the eastward extrusion material from the Qinghai-Tibet Plateau had gone. Overall, that yangtze Block was subjected to thrusting of the crustal materials from the orogenic belts over its both sides. This finding has implications for the study of the intracontinental orogenic mechanism in South China, the reconstruction of tectonic evolutionary history and the kinematics processes during the lateral extrusion of the Tibet Plateau.

关键词： Geophysics Crustal structure Subduction of the yangtze Block eastern margin of the Tibetan Plateau Jiangnan-Xuefeng orogenic belt

effect of Lead on Soil enzyme Activities in Two Red Soils

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Pedosphere 2014年第6期24卷 817-826页

作者： yang Jin-Yan He Zhen-Li yang Xiao-e LI Ting-Qiang College of Architecture and environment Sichuan University College of environmental and Resource Sciences Zhejiang University University of Florida IFASIRRECFort PierceFL 34945 (USA)

enzyme activities have the potential to indicate biological functioning of soils. In this study, soil urease, dehydrogenase, acid phosphatase and invertase activities and fluorescein diacetate(FDA) hydrolysis were measured in two red soils spiked with Pb2+ranging from 0 to 2 400 mg kg-1to relate the enzyme activity values to both plant growth and the levels of available and total Pb2+concentrations in soils, and to examine the potential use of soil enzymes to assess the degrees of Pb contamination. Soil samples were taken for enzyme activities assaying during 3 month's incubation and then after planting of celery(Apium graveolens L.) and Chinese cabbage(Brassica chinensis L.). enzyme activities in the red soil derived from arenaceous rock(RAR) were generally lower than those in the red soil developed on Quaternary red earths(ReQ). At high Pb2+loadings, in both incubation and greenhouse studies, urease activity and FDA hydrolysis were significantly inhibited. But there were no significant relationships between soil dehydrogenase, acid phosphatase or invertase activity and soil Pb2+loadings in both RAR and ReQ soils. The growth of celery and Chinese cabbage increased soil urease activity and FDA hydrolysis, but had minimal effect on dehydrogenase and invertase activities. There were positive correlations between celery biomass and soil urease activity and FDA hydrolysis. These results demonstrate that urease activity and FDA hydrolysis are more sensitive to Pb2+than acid phosphatase, dehydrogenase and invertase activities in the RAR and ReQ soils.

关键词： fluorescein diacetate hydrolysis heavy metal plant biomass urease

Root Morphology and Zn^2＋ Uptake Kinetics of the Zn Hyperaccumulator of Sedum alfredii Hance

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Journal of Integrative Plant Biology 2005年第8期47卷 927-934页

作者： Ting-Qiang LI Xiao-e yang Zhen-Li He Jin-Yan yang Ministry of education Key Laboratory of environmental Remediation and ecosystem Health Zhejiang University Huajiachi Campus Hangzhou 310029 China University of Florida Indian River Research and Education Center Fort Pierce Florida 34945 USA

Root morphology and Zn^2＋ uptake kinetics of the hyperaccumulating ecotype （He） and nonhyperaccumulating ecotype （NHe） of Sedum alfredii Hance were investigated using hydroponic methods and the radiotracer flux technique. The results indicate that root length, root surface area, and root volume of NHe decreased significantly with increasing Zn^2＋ concentration in growth media, whereas the root growth of He was not adversely affected, and was even promoted, by 500μmol/L Zn^2＋. The concentrations of Zn^2＋ in both ecotypes of S. alfredii were positively correlated with root length, root surface area and root volumes, but no such correlation was found for root diameter. The uptake kinetics for ^65Zn^2＋ in roots of both ecotypes of S. alfredii were characterized by a rapid linear phase during the first 6 h and a slower linear phase during the subsequent period of investigation. The concentration-dependent uptake kinetics of the two ecotypes of S. alfredii could be characterized by the Michaelis-Menten equation, with the Vmax for ^65Zn^2＋ influx being threefold greater in He compared with NHe, indicating that enhanced absorption into the root was one of the mechanisms involved in Zn hyperaccumulation. A significantly larger Vmax value suggested that there was a higher density of Zn transporters per unit membrane area in He roots.

关键词： phytoremediation Sedum alfredii translocation uptake kinetics zinc (Zn).

NON-PROPAGATING SOLITARY SURFACe WAVe IN AN ANNULAR TROUGH

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Chinese Physics Letters 1989年第12期6卷 537-540页

作者： YAN Jiaren yang Xin e Department of Physics Xiangtan UniversityXiangtan 411105 Department of Physics Tianjin UniversityTianjin 300072

The nonlinear equation governing the nonpropagating solitary surface wave and its single solitary wave solution were derived by the method of multiple *** results obtained were compared with that in rectangular trough.

关键词： solitary wave SURFACe

Uncertainty Assessment of Soil erosion Model Using Particle Filtering

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Journal of Mountain Science 2015年第4期12卷 828-840页

作者： Yeonsu KIM Giha Lee Hyunuk AN Jae e yang International Water Resources Research Institute Chungnam National University Dept.of Construction & Disaster Prevention eng. Kyungpook National University Dept.of Agricultural & Rural eng. Chungnam National University Dept.of Biological environment Kangwon National University

Recent advances in computer with geographic information system(GIS) technologies have allowed modelers to develop physics-based models for modeling soil erosion processes in time and ***, it has been widely recognized that the effect of uncertainties on model predictions may be more significant when modelers apply such models for their own modeling *** of uncertainty involved in modeling include data, model structural, and parameter *** deal with the uncertain parameters of a catchment-scale soil erosion model(CSeM) and assess simulation uncertainties in soil erosion, particle filtering modeling(PF) is introduced in the *** proposed method, CSeM-PF, estimates parameters of non-linear and non-Gaussian systems, such as a physics-based soil erosion model by assimilating observation data such as discharge and sediment discharge sequences at *** provides timevarying feasible parameter sets as well as uncertainty bounds of outputs while traditional automatic calibration techniques result in a time-invariant global optimal parameter ***-PF was applied to a small mountainous catchment of the Yongdamdam in Korea for soil erosion modeling and uncertainty assessment for three historical typhoon ***, the most optimal parameter sets and uncertainty bounds of simulation of both discharge and sediment discharge at each time step of the study events are provided.

关键词： Data assimilation Particle filter Soil erosion modeling Parameter estimation Time variant parameter Mountainous catchment

Synthesis of M_xH_yTi_3O_7 nanotubes by simple ion-exchanged process and their adsorption property

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Chinese Science Bulletin 2007年第18期52卷 2491-2495页

作者： SONG XuChun yang e ZHeNG YiFan Department of Chemistry Fujian Normal University Fuzhou 350007 China College of Chemical engineening & Materials Science Zhejiang University of Technology Hangzhou 310004 China

The MxHyTi3O7 (M=K, Fe, Zn, Co, Na, Ag) nanotubes were prepared by ion-exchange reactions, in which H2Ti3O7 nanotube reacted with salts of K2SO4, Na2SO4, Fe(NO3)3, ZnSO4, Co(NO3)2 and AgNO3 in solution respectively. The properties of products were characterized by SeM, TeM, XRD and eDX. Synthesis of MxHyTi3O7 nanotubes by ion-exchanged process was proved by our experimental results. The adsorp- tion properties of MxHyTi3O7 nanotube for methylene blue in aqueous solution were studied.

关键词：纳米材料钛酸盐纳米管离子交换过程吸收特征