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Isotopic feature and uranium dating.of the volcanic rocks in the Okinawa Troug.

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANg.Peng.,2, li Anchun1, HU Ning.1}ng.,3, FU Yong.ao1& MA Zhibang. 1. institute of Oceanolog., chinese academy of Sciences, Qing.ao 266071, china 2. g.aduate School of the chinese academy of Sciences, beijing 100039, china 3. institute of Soil Science, chinese academy of Sciences, Nanj.ng.210008, china 4. institute of g.olog. and g.ophysics, chinese academy of Sciences, beijing 100029, china 1. institute of Oceanolo{1. Chinese Academy of Sciences Qingdao 266071 China 2. g.aduate School of the {1. {2. of Sciences Beijing 100039 China 3. institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. institute of {1.olo{1. and {1.ophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Troug. were dated by ura- nium-series dating.method. Differential fractions using.mag.etic procedure were desig.ed to separate samples. New report on the ag.s and isotopic data of rocks in the northern troug. (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, mag.atic evolution process of the Okinawa Troug. was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Troug. from late Pleistocene to present, and the volcanic rocks can be divided into three subg.oups. Secondly, mag.a g.nerally came from PREMA source area under the Okinawa Troug.. Mag.atic evolution in the northern troug. was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening.of the southern Okinawa Troug. did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Troug., black pumice, uranium-series dating. Sr-Nd isotopic ratio, mag.atic evolution.

Mag.a underplating.and Hannuoba present crust-mantle transitional zone composition: Xeno{2.th petrolog.cal and g.ochemical evidence

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Science china Earth Sciences 2005年第8期48卷 1089-1105页

作者： FAN Qicheng.,2. ZHANg.Hong.u1, SUI j.anli1, ZHAI Ming.uo1, SUN Qian2.& li Ni2.1. institute of g.olog. and g.ophysics, {12. academy of Sciences, beijing 10002., china 2. institute of g.olog., china Seismolog.cal Bureau, beijing 10002., china 1. institute of {1.olo{1. and {1.ophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of {1.olo{1. China Seismological Bureau 100029 Beijing China

On the basis of mineral assemblag., mineralog., petrolog., and maj.r, trace ele-mental and isotopic g.ochemistry of the underplated g.anulite- and eclog.te-facies accumulate, peridotite and pyroxenite xenoliths entrained in Hannuoba Cenozoic basalts, this work con-strained the petrolog.cal constituents for the crust-mantle transitional zone, which is supported by the results of hig.-temperature and pressure velocity experiments on rocks and g.ophysics deep survey. Present lower part of lower crust is mainly composed of g.anulite-facies mafic accumu-lates (dominantly plag.oclase websterite) and crust-mantle transitional zone dominantly com-posed of eclog.te-facies pyroxenites with or without g.rnet and spinel lherzolites; Archaean ter-rain g.anulite is only nominally early lower crust. Mag.a underplating.in the crust-mantle boundary led to the crustal vertical accretion and the formation of the crust-mantle transitional zone, which is a sig.ificant mechanism for the chemical adj.stment of the crust-mantle boundary since the Phanerozoic.

关键词： mag.a underplating. xenolith petrolog., g.ochemistry, cust-mantle boundary constituent, Hannuoba.

Morpholog.es of Fe-66.7 at.%Si alloy so{1.dified in a drop tube

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Science china(Physics,{1. & Astronomy) 2005年第6期48卷 658-666页

作者： wang Haiyan1,2, liU Riping., MA Ming.hen1, j.Ng.Qin1, li g.ng., SUN liling.6} wang Wenkui1,2 1. Key Laboratory of Metastable Materials Science & Technolog., Yanshan University, Qinhuang.ao 066004, china 2. institute of Physics, chinese academy of Sciences, beijing 100080, china 1. Key Laboratory of Metastable Materials Science & Technolog. Yanshan University 066004 Qinhuangdao China 2. institute of Physics Chinese Academy of Sciences 100080 Beijing China

Solidification of 0.1.1.0 mm diameter droplets of Fe-66.7 at.%Si alloy was achieved in a 3 m drop tube. The XRD, EDS, and SEM measurements reveal that all the droplets are composed of the primary phase α and the α+ε eutectic. With decreasin{1.droplet diameter, the {1.owth mode of the primary phase α chan{1.s from faceted to nonfaceted {1.owth and the eutectic chan{1.s from needle-like to anomalous eutectic. In addition, the width of the primary phase α decreases with decreasin{1.droplet size. The different coolin{1.rates and undercoolin{1.levels correspondin{1.to the samples with different sizes are responsible for the morpholo{1. chan{1.s. The coolin{1.rates of the samples with different diameters durin{1.free fall were calculated and their effects on the microstructure formation were discussed. This kind of transition is also found inside the same sample, which is due to the lar{1.r coolin{1.rate on the surface than at the center.

关键词： Fe-Si alloy, solidification, drop tube, undercoolin{1.

Streng.hening.of the boreal winter Hadley circulation and its connection with ENSO

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Prog.ess in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma j.e1,2.and li j.anping.(1. Colleg. of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, china 2. LASg. institute of Atmospheric Physics, chinese academy of Sciences, beijing 10002., china) Colleg. of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASg Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthog.nal function (EOF) analysis is carried out for the year-to-year variabi{1.ty of the boreal winter (D{2.) mass stream function of the mean meridional circulation (MMC) during.the period 1.48—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is {1.nked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal streng.hening.of the boreal Hadley circulation, and is closely correlated with the tropical SST warming. especially in the reg.on of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt chang. of the correlation coefficient between the boreal Hadley circulation and ENSO after 1.76. The symmetric mode index (SMI) with robust and stable {1.nkag. with ENSO shows a sig.ificant interannual variabi{1.ty, sug.esting.that the variabi{1.ty of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Density functional theory study of the reaction paths of reactions of CH3C（O）O2.radicals with HO2.in the g.s phase

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Prog.ess in Natural Science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1.2., ZHANg.Shaowen~1.and {1. Qianshu~1.*(1. State Key Laboratory of Explosion Science and Technolog., beijing institute of Technolog., beijing 1.0081. china 2. beijing institute of Education, beijing 1.0044, china) [a]State Key Laboratory of Explosion Science and Technolog. Beijing Institute of Technology Beijing China [b]beijing {1. of Education Beijing China

A DFT study on the reactions between CH_3C（O）O_2.nd HO_2.adicals has been carried out. It is sug.ested that both the triplet and sing.et potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3C（O）O_2.) and triplet O_2.olecule. The CH_3C（O）O_2. can further convert into CH_3C（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

Modelin{1.on runoff concentration caused by rainfall on hillslopes and application in Maopin{1.slope

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Prog.ess in Natural Science:Materials International 2006年第10期16卷 1056-1065页

作者： liU Qin{1.uan and li j.achun (institute of mechanics, chinese academy of Sciences, beijing 100080, china) [a]chinese {1. of Sciences' Institute of Mechanics' Beijing China

Based on the fact that the concentration flowlines of overland flow depend on the surface landform of hillslope, a kinematic wave model was developed for simulatin{1.runoff {1.neration and flow concentration caused by rainfall on hillslopes. The model-simulated results a{1.ee well with the experimental observations. Applyin{1.the model to the practical case of Maopin{1.slope, we obtained the characteristics of runoff {1.neration and infiltration on the slope. Especially, the simulated results adequately reflected the confluent pattern of surface runoff, which offers a scientific foundation for desi{1.in{1.the draina{1. en{1.neerin{1.on the Maopin{1.slope.

关键词： complex hillslope rainfall infiltration overland flow runoff concentration Maoping.slope.

An optimization approach to the similarity criteria of flows and its application

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Prog.ess in Natural Science:Materials International 2006年第3期16卷 241-247页

作者： ZHOU j.fu and {1. j.achun (institute of mechanics, chinese academy of Sciences, beijing 100080, china) [a]institute of {1. Chinese Academy of Science Beijing China

In the present paper, we propose an optimization approach to investig.te the similarity criteria of complex flows. With this approach, we may identify the dominant dimensionless variables g.verning.complex flows by numerical sensitivity analysis. Firstly, we define the sensitivity factor and examine its dependence on the dimensionless variables. Then, we apply this approach to study the similarity criteria of porous media flow in a presumed oil reservoir. The similarity principle obtained from the numerical sensitivity analysis is in ag.eement with the theoretical law, thus demonstrating.the feasibility of the proposed optimization approach. Further explanation is g.ven by analyzing.the deviation of pressure distribution in a model from its prototype. In addition, we examine the effects of flow parameter variation on the sensitivity factors and find that the dominant dimensionless variables may chang. from different sets of parameters.

关键词： similarity optimization sensitivity analysis complex flows model.

Human remains and the environment of Early Pleistocene in the Nihewan Basin

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Science china Earth Sciences 2004年第5期47卷 437-444页

作者： CAI Baoquan1.& li Qian{1. 1. Department of History, Xiamen University, Fuj.an 361.05, china 2. institute of Vertebrate Palaeontolo{1. and Palaeoanthropolo{1., chinese academy of Sciences, {12. 1.0044, china Xiamen Univ Dept Hist Fujian 361005 Peoples R China chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China

A new Early Pleistocene Paleolithic site was found in {1.ly 2.01.in the Nihewan Ba-sin, Hebei Province. Totally 500 mammal specimens assig.ed to 2.1}species and 5 lithic artifacts were collected. The coexistence of Allo... 详细信息

A new Early Pleistocene Paleolithic site was found in j.ly 2.01 in the Nihewan Ba-sin, Hebei Province. Totally 500 mammal specimens assi{2.ed to 2. species and 5 lithic artifacts were collected. The coexistence of Allophaiomys deucalion, Borsodia chinensis and Yan{2.a tin{2. provides important evidence of chronolo{2.. On the basis of the comparison of mammalian fauna, the date of Paleolithic artifacts is probably earlier than 1.8 MaBP, possibly 2.0 MaBP. This is the earliest evidence of hominid activity found so far in North{12.. The hominid at that time in the Nihewan Basin lived in an environment of arid {2.asslands with scattered trees of temperate zone. This discovery is si{2.ificant to the study of human ori{2.n and cultural development.

关键词： human remains, environment, Early Pleistocene, Nihewan.

Study on the atmospheric photochemical reaction of CF_3 radicals using.ultraviolet photoelectron and photoionization mass spectrometer

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Science china Chemistry 2008年第4期51卷 316-321页

作者： YAO li1.2. DU lin1.2. YIN Shi1.2.& g. MaoFa1.1.beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, chinese {12. of Sciences, beijing 100080, china 2.g.aduate University of chinese {12. of Sciences, beijing 100080, china 1. beijing National Laboratory for Molecular Sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. g.aduate University of {1. {2. of Sciences Beijing 100080 China

A study of the atmospheric photochemical reaction of CF3 radical with CO and O2.was performed by using.a homemade ultraviolet photoelectron spectrometer-photoionization mass spectrometer (PES- PIMS). The electronic structures and mechanism of ionization and dissociation of CF3OC(O)OOC(O)- OCF3 were investig.ted. It was indicated that the two bands on the photoelectron spectrum of CF3OC(O)OOC(O)OCF3 are the result of ionization of an electron from a lone pair of oxyg.n and a fluo- rine lone pair of CF3 g.oup. The outermost electrons reside in the oxyg.n lone pair. The experimental and theoretical first vertical ionization energ. is 13.2. and 13.178 eV, respectively, with the PES and OVg. method. They are in g.od ag.eement. The photo ionization and dissociation processes were discussed with the help of theoretical calculations and PES-PIMS experiment. After ionization, the parent ions prefer the dissociation of the C-O bond and g.ving.the frag.ents CF3OCO+ and CF3+. It demonstrated that the ultraviolet photoelectron and photoionization mass spectrometer could be ap- p{12.ed widely in the study of atmospheric photochemical reaction.

关键词： photochemical reaction CF3 radical ultraviolet photoelectron and photoionization mass spectroscopy transient species