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Energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2.)Shui-Cai WANG~2.Jun-Fang HE~2.Hui CHEN~3 1 Institute of Photonics and Photo-Technology,northwest university,xi'an{2.,china 2.State Key Laboratory of Transient Optics and Photonics,xi 'an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,xi'an 710068.china 3 Laboratoty of Photosynthesis Basic Research,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,china Institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China Laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb62.,Chlb646,Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83were discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 62. nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.Energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83were determined to be 1.44ns,1.43 ns,636 ps and 713 ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

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Thermochemistry on coordination behavior of samaric chloride hydrate with diethylammonium diethyldithiocarbamate

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Rare Metals 2004年第3期23卷 203-208页

作者： JIAOBaojuan RENYixia CHENSanping GAOShengli ZHAOFengqi SHIQizhen departmentofChemistry ShaanxiKeyLaboratoryofPhysico-InorganicChemistryNorthwestUniversityXi＇an710069China xi＇anModemChemistryResearchInstitute Xi＇an710072China departmentofChemistry ShaanxiKeyLaboratoryofPhysico-InorganicChemistryNorthwestUniversityXi＇an710069China

The complex of samaric chloride lower hydrate with diethylammoniumdiethyldithiocarbamate (D-DDC) was synthesized conveniently in absolute alcohol and dry N_2.tmosphere. The title complex was identified as Et_2.H_2.Sm(S_2.NEt_2._4] by chemical and elementalanalyses, the bonding characteristics of which was characterized by IR. The enthalpies of solutionof samaric chloride hydrate and D-DDC in absolute alcohol at 2.8.15 K and the enthalpies change ofliquid-phase reaction of formation for Et_2.H_2.Sm(S_2.NEt_2._4] at different temperatures weredetermined by mi-crocalorimetry. On the basis of experimental and calculated results, threethermodynamic parameters (the activation enthalpy, the activation entropy, and the activation freeenergy), the rate constant, and three kinetic parameters (the apparent activation energy, thepre-exponential constant, and the reaction order) of liquid phase reaction of formation wereobtained. The enthalpy change of the solid-phase title reaction at 2.8.15 K was calculated by athermochemical cycle.

关键词： inorganic chemistry thermochemistry microcalorimetric method samaricchloride hydrate diethylammonium diethyldithiocarbamate (D-DDC)

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Synthesis and Crystal Structure of Binuclear Complex of Copper(Ⅱ)Chloroacetate with Acetamine

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Chinese Journal of Structural Chemistry 1999年第2期18卷 19-22页

作者： SHI Qian WANG Yao Yu ② TANG Zong Xun SHI Qi Zhen (department of Chemistry, northwest university,{2. 710069) 西北大学化学系陕西西安 710069

The title complex, Cu 2.O 2.CH 2.l) 4 OC(NH 2.CH 3 2. crystallizes in space group P2. 1/a with a=7.616(4), b=18.665(5), c=7.949(5) , β=106.2.(5)°. V=1084(1)  3, Z=2. M r=619.19, D c =1.896 g/cm 3; μ =2..05 cm -1 and F(000)=62..00, R =0.045 and R w =0.054 for 1807 observable reflections. X ray crystal structure analysis revealed that two Cu atoms are bridged by four chloroacetate groups, and the acetamine ligands are bonded by O(carboxide) to the terminal Cu atoms of each dimeric unit. The coordination geometry of Cu atom is a distorted octahedral configuration. The distance between the two Cu atoms is 2.648(1) .

关键词： copper(Ⅱ) chloroacetate binuclear complex crystal structure

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Parameter-Free Shifted Laplacian Reconstruction for Multiple Kernel Clustering

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1072-1074页

作者： xi Wu Zhenwen Ren F.Richard Yu the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010China the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010 the Guangxi Key Laboratory of Machine Vision and Intelligent Control Wuzhou UniversityWuzhou 543002 the Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen 518060China

Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2.Only considers the clustering information,but ignores the interference of noise within Laplacian.

关键词： parameter letter Parameter

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Liquid-solid adsorption from binary component mixture

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Chinese Journal of Chemistry 1993年第5期11卷 385-394页

作者： GENG,xin-Peng department of Textile Chemical Engineering,northwest Textile Engineering Institute,xi’an 710048GENG,xin-Du department of Chemistry,northwest university,xi’an 710069 department of Textile Chemical Engineering Northwest Textile Engineering Institute Xi'an 710048 department of Chemistry Northwest University Xi'an 710069

Based on five thermodynamic equilibria among the components Ⅰ,Ⅱ,and adsorbent,a stoichiometric displacement model of adsorption(SDM-A)from binary liquid mixture with complete range of concentration in liquid-solid system is proposed and tested by using data published in litera- *** two expressions of this model show the quantitative relationships between the activity of the component Ⅰ on the surface and that in the bulk solution and between its partition coefficient in two phases and its equilibrium activity in bulk solution,*** some cases,the two expressions may become two linear equations,from which the correspondingly linear slopes(*** adsorption parameters)are obtained with which the stoichiometric displacement relation and relative adsorption ability between components Ⅰ and Ⅱ can be *** effectiveness of these two expressions for different adsorption systems and the similarity and difference between SDM-A and the Freundlich Em- pirical Equation are also investigated.A rule illustrating a parallel relationship between 2./Z and the property of bulk solution is also ***,having studied the quantitative relation of the adsorption from either ideal or non-ideal liquid mixture and compaired their linear adsorption parameters,we find that SDM-A is much better than the Langmuir's.

关键词： adsorbent thermodynamic similarity partition adsorbed equilibria elucidated naked stoichiometric absolute

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Environmental records of lacustrine sediments in different time scales:Sediment grain size as an example

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Science china Earth Sciences 2004年第10期47卷 954-960页

作者： CHEN Jing’an1, WAN Guojiang1, David Dian Zhang2. ZHANG Feng1 & HUANG Ronggui1 1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. department of Geography and {2., university of Hong Kong, Pokfulam Road, Hong Kong, china 1. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of Geography and geology University of Hong Kong Pokfulam Road Hong Kong China

Sediment grain size is a conventional proxy of climatic changes. Larger sediment grain size is often interpreted to indicate dry climate during lower lake level while smaller sedi- ment grain size implies wet climate during higher lake level. Through detailed study on sediment grain sizes in Lake Erhai and Lake Chenghai, this paper reveals the different indication signifi- cances of sediment grain sizes in different time scales, different resolution investigations. For long time-scale and low resolution (102. or 103a) studies, larger sediment grain size indicates lower lake level, smaller lake area and drier climate while smaller sediment grain size indicates higher lake level, larger lake area and wetter climate. For short time-scale and high resolution (a or 10a) studies, larger sediment grain size reflects more rainfall and wetter climate while smaller sediment grain size reflects less rainfall and drier climate. Environmental information revealed by lacustrine sediment records is often different in different time scales because of the variance of sedimentation resolution, sampling resolution and dating precision. Therefore, paleoclimate im- plications of environmental proxies in long time-scale and low resolution investigations could not be mechanically applied to short time-scale and high resolution studies. Only after synthetically analyzing the influence manner and extent of all factors on the sediment records in different time scales, can credible conclusions be obtained.

关键词： lacustrine sediment, environmental record, grain size, time scale.

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Geochemistry of the high-Mg andesites at Zhangwu, western Liaoning: Implication for delamination of newly formed lower crust

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Science china Earth Sciences 2007年第12期50卷 1773-1786页

作者： HUANG Hua1,GAO Shan1,2.HU ZhaoChu1,LIU xiaoMing2.& YUAN HongLing2.1 State Key Laboratory of Geological Processes and Mineral Resources,china university of Geosciences,Wuhan 430074,china 2.State Key Laboratory of Continental Dynamics,department of geology,northwest university,xi’an 710069,china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China

Ten volcanic samples at Zhangwu,western Liaoning Province,North china were selected for a sys-tematic geochemical,mineralogical and geochronological study,which provides an opportunity to ex-plore the interaction between the continental crust and mantle beneath the north margin of the North china *** one basalt sample(SiO2. 50.2.%),the other nine samples are andesitic with SiO2.contents ranging from 53% to 59%.They have relatively high MgO(3.4%―6.1%,Mg#=50―64) and Ni and Cr contents(Ni 2.×10?6―197×10?6,Cr 51×10?6―478×10?6).Other geochemical characteristics of Zhangwu high-Mg andesites(HMAs) include strong fractionation of light rare earth elements(LREE) from heavy rare earth elements(HREE),and Sr from Y,with La/Yb greater than 15,and high Sr/Y(34― 115).Zircons of andesite YX2.0 yield three age groups with no Precambrian age,which precludes ori-gin of the Zhangwu HMAs from the partial melting of the Precambrian *** oldest age group peaking at 2.3 Ma is interpreted to represent the collision of the Siberia block and the North china block,resulting in formation of the Central Asian orogenic belt by closure of the Mongol-Okhotsk *** intermediate age group corresponds to the basalt underplating which caused the wide-spread coeval granitoids in the North china craton with a peak 2.6Pb/2.8U age of 172.*** youngest age group gives a 2.6Pb/2.8U age of 12.±2.Ma,which is interpreted as the eruption age of the Zhangwu *** high 87Sr/86Sri(12. Ma)>0.706 and low εNd(t)= ?6.36―?13.99 of the Zhangwu HMAs are distinct from slab *** common presence of reversely zoned clinopyroxene phenocrysts in the Zhangwu HMAs argues against the origin of the Zhangwu HMAs either from melting of the water saturated mantle or melting of the lower *** light of the evidence mentioned above,the envisaged scenario for the formation of the Zhangwu HMAs is related to the basaltic underplating at the base of the crust,which led to the thickening of the lower crust and

关键词： Zhangwu HMAs, basalt underplating, newly formed lower crust, delamination, North china craton

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Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science china Earth Sciences 2006年第9期49卷 904-914页

作者： WANG xiaorui1, GAO Shan1,2. LIU xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3 & WANG Xuance4 1. State Key Laboratory of Continental Dynamics, department of geology,{2., xi`an 710069, china 2. State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Wuhan 430074, china 3. Shenyang Institute of geology and Mineral Resources, Shenyang 110032. china 4. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 1. State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China 2. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 3. Shenyang Institute of geology and Mineral Resources Shenyang 110032 China 4. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2.= 52.82.59.31 wt%, Al_2._3=14.15-16.35wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03-1.88 μg/g) and Y(12.2. μg/g) and high Sr (62.-132. μg/g) and Sr/Y(32.88), withhigh La_N/Yb_N ratio (10-2.). They share similar major and trace element characteristics to volcanicrocks from the xinglonggou Formation except their lower Nd isotope ratios (^(143)Nd/^(144)Nd(130Ma) = 0.5118-0.5119, ε_(Nd) (130Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (130 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North china craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 12. to 130 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2.for samples with SiO_2.> 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North china Craton, delamination.

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“Blocking and rebalance”mechanism-guided design strategies of bimetallic doped 2. a-phosphorus carbide as efficient catalysts for N_(2. electroreduction

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Journal of Energy Chemistry 2024年第10期97卷 68-78,I0003页

作者： Cheng He Jianglong Ma Shen xi Wenxue Zhang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong UniversityXian 710049ShanxiChina School of Materials Science and Engineering Chang'an UniversityXi'an 710064ShaanxiChina

Compared to single atom catalysts(SACs),the introduction of dual atom catalysts(DACs)has a significantly positive effect on improving the efficiency in the electrocatalytic nitrogen reduction reaction(NRR)which provides an environmental alternative to the Haber-Bosch ***,the research on the mechanism and strategy of designing bimetallic combinations for better performance is still in its early ***,based on"blocking and rebalance"mechanism,45 combinations of bimetallic pair dopedα-phosphorus carbide(TM_(A)TM_(B)@PC)are investigated as efficient NRR catalysts through density functional theory and machine learning *** a multi-step screening,the combinations of TiV,TiFe,MnMo,and FeW exhibit highly efficient catalytic performance with significantly lower limiting potentials(-0.17,-0.18,-0.14,and-0.30 V,respectively).Excitingly,the limiting potential for CrMo and CrW combinations is 0 V,which are considered to be extremely suitable for the NRR *** mechanism of"blocking and rebalance"is revealed by the exploration of charge transfer for phosphorus atoms in electron blocking ***,the descriptorφis proposed with machine learning,which provides design strategies and accurate prediction for finding efficient *** work not only offers promising catalysts TM_(A)TM_(B)@PC for NRR process but also provides design strategies by presenting the descriptorφ.

关键词： DACs Nitrogen reduction reaction 2. a-phosphorus carbide Inherent attributes Machine learning

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Transitional function of DG to CA3 in the hippocampus

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Progress in Natural Science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1 and Liu Shenquan2.1. department of Mathematics, Hangzhou Normal university, Hangzhou 310036,{2. 2. department of Applied Mathematics, School of Mathematical Sciences, South{2. university of Technology, Guangzhou 510640,{2.) department of Mathematics Hangzhou Normal University Hangzhou 310036 China department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

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