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Effect of Anion Surface Active Agent on the Preparation of SrTiO3 Nano-Crystals

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稀有金属材料与工程 2006年第S3期 603-604页

作者： Qingli Ren~1 Qiang Luo~2.Quanxi Cao~1 (1.School of Technical Physics,xidian university,xi'an 710071,China) (2.The Second Artillery engineering {2.,xi'an 71002.,China)

SrTiO3nano-crystal samples with floccule or flake crystal morphology,which were indexed as a perovskite-type crystal structure based on the results of XRD and TEM,were successfully prepared by one-step liquid reaction *** the growth mechanism of the SrTiO3nano-crystals under the liquid condition with/without adding the surface active agent was *** was found that adding the surface active agent contributes to the processing in which the ions gathering bodies transit to a more stable phase through the chemical reaction and form the flake SrTiO3nano-crystals.

关键词： nano-crystals SrTiO3 anion surface active agent technology processing

Topological superconductors with spin-triplet pairings and Majorana Fermi arcs

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Chinese Physics B 2024年第8期33卷 453-458页

作者：黄石罗熙 college of Science University of Shanghai for Science and TechnologyShanghai 200093China

We construct a three-dimensional topological superconductor Bogoliubov–de Gennes(BdG)Hamiltonian with the normal state being a three-dimensional topological *** introducing inter-orbital spin-triplet pairings term△3,there are topological Majorana nodes in the bulk and they are connected by Majorana Fermi arcs on the surface,similar to the case of Weyl ***,by adding an inversion-breaking term to the normal state,momentum-independent pairing terms with different parities can coexist in the Bd G Hamiltonian,which creates more Majorana modes similar to Andreev bound states and a richer phase diagram.

关键词： topological surface states topological superconductors topological nodes Weyl points Majorana Fermi arcs

Timing and geochemical characters of the Sanchazi magmatic arc in Mianlüe tectonic zone,South Qinling

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Science China Earth Sciences 2004年第4期47卷 317-328页

作者： LI Shuguang1, HOU Zhenhui1, YANG Yongcheng2. SUN Weidong1,1), ZHANG Guowei3, & LI Qiuli1 1. School of Earth and Space Sciences,university of Science and Technology of China ,Hefei 2.002.,China 2. Regional geological Survey Team of Shaanxi Province,xianyang 712.00, China 3. Department of Geology, Northwest university,xi抋n 710069, China Present address: Max-Planck-Institut f. Chemie Postfach 3060 55020 Mainz Germany School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Regional geological Survey Team of Shaanxi Province Xianyang 712000 China Department of Geology Northwest University Xi’an 710069 China

The Sanchazi mafic-ultramafic complex in Mianlüe tectonic zone,South Qinling can be subdivided into two blocks,*** paleo-magmatic arc and Zhuangkegou paleo-oceanic crust fragment (ophiolite).The Sanchazi paleo-magmatic arc is mainly composed of ande-site,basaltic and basalt-andesitic gabbro(or diorite),andesitic dyke,plagiogranite and minor ul-tramafric rocks,which have typical geochemical features of island arc volcanic rocks,such as high field strength element(***,Ti)depletions and lower Cr,Ni *** Light rare earth element (LREE) and K enrichments of these rocks and zircon xenocrystals of 900 Ma from plagiogranite suggest that this magmatic arc was developed on the South active continental margin of the South Qinling *** U-Pb age of (300±61) Ma for zircons from plagiogranite in-dicates that the Mianlüe paleo-oceanic crust was probably subducted underneath the South Qinling micro-continent in *** is consistent with the formation time (309Ma) of the Huwan eclogite originating form oceanic subduction in Dabie Mountains,suggesting that the Mianlüe paleo-ocean probably extended eastward to the Dabie Mountains in *** high-Mg adakitic rocks in Sanchazi paleo-magmatic arc suggest thet the subducted oceanic crust was relatively young (2.Ma) and hot.

关键词： Qinling orogen, magmatic arc, U-Pb zircon age, ophiolite complex.

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

Evaporative Condensers in Comfortable Air Conditioning System

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湖南大学学报（自然科学版） 2009年第S1期36卷 136-140页

作者： YIN Ying-de1,ZHU Dong-sheng1,DU Gui-mei2.LI Yuan-xi1,SUN He-jing1,LIU Qing-ming1(1.Key Lab of Enhancement Heat Transfer and Energy Conservation,the Ministry of Education,South China university of Technology,Guangzhou,Guangdong 510641,China 2.college of Civil {2.,Hunan university,changsha,Hunan 410082.China) Key Lab. of Enhancement Heat Transfer and Energy Conservation South China University of Technology Guangzhou 510641 China college of Civil engineering Hunan University Changsha 410082 China

The operating theory of an evaporative condenser was *** difference between an evaporative condensing refrigeration system and a general refrigeration system was *** with the air-cooled and the water-cooled,the virtues of energy-conservation and water-conservation of evaporative condensers were *** questions existing in the application of evaporative condensers were pointed out,the corresponding solving methods were analyzed accordingly,and the development trend of evaporative condensing technique in mechanical refrigeration system field and the applied foreground of evaporative condensers in comfortable air conditioning were prospected.

关键词： evaporative condensers evaporative condensing refrigeration system general refrigeration system comfortable air conditioning system

Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science China Earth Sciences 2011年第4期54卷 493-508页

作者： xiAO Liang 1,2.3,4,SUN BaiNian 1,2.,LI xiangChuan 1,REN Wenxiu 1 &JIA Hui 1 1 Key Laboratory of Western China's Environmental Systems of the Ministry of Education and college of Earth and Environment Science,Lanzhou university,Lanzhou 730000,China 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 2.0008,China 3 college of Arts and Sciences,Bryant university,Smithfield RI 02.17,U.S.A. 4 Key Laboratory of Western China's Mineral Resources and geological engineering of Ministry of Education,chang’an university,xi’an 710054.China 1. Key Laboratory of Western China’s Environmental Systems of the Ministry of Education and college of Earth and Environment Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene xiannanshan Formation,Zhejiang Province(eastern China) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene xiananshan Formation sun and shade leaves

SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau

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Science China Earth Sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2.& SU Li3 1 Institute of Geology, Chinese Academy of geological Sciences, Beijing 100037, China 2.college of Earth Sciences, Jilin {2., changchun 130061, China 3 The geological Laboratory Center and State Key Laboratory of geological Processes and Mineral Resources, China {2. of Geo- sciences, Beijing 100083, China 1. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China2. College of Earth Sciences Jilin University Changchun 130061 China3. The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.2.2.15 to 0.2.2.57, with εHf(t) values of 5.02.0.2., indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the xiangxi Bay

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Science China(Technological Sciences) 2010年第4期53卷 1114-1125页

作者： YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2.& xiAO ShangBin1,3 1 college of Civil & Hydroelectric engineering,China Three Gorges {2.,Yichang 443002.China 2.School of Water Resources & Hydropower engineering,Wuhan {2.,Wuhan 430072.China 3 Institute of Earth Environment,Chinese Academy of Sciences,xi’an 710075,China 1. college of Civil & Hydroelectric engineering China Three Gorges University Yichang 443002 China2. School of Water Resources & Hydropower Engineering Wuhan University Wuhan 430072 China3. Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,*** hydrodynamic parameters and water quality parameters(*** velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 *** water exchange between the mainstream(the changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different *** water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding ***,the water stability index in the mainstream remained small but it was lowered in the *** main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding *** grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the ***,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

关键词： impounding density current eutrophication the xiangxi Bay the Three Gorges Reservoir

Petrogenesis of Indosinian volcanic rocks in Songpan-Garze fold belt of the northeastern Tibetan Plateau:New evidence for lithospheric delamination

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Science China Earth Sciences 2010年第9期53卷 1316-1328页

作者： CAI HongMing1,2. ZHANG HongFei1,2. XU WangChun1,2. SHI ZhangLiang1,2.& YUAN HongLin3 1 State Key Laboratory of geological Processes and Mineral Resources, Wuhan 430074, China 2.Faculty of Earth Sciences, China university of Geosciences, Wuhan 430074, China 3 State Key Laboratory of Continental Dynamics, Northwest university, xi’an 710069, China 1. State Key Laboratory of geological Processes and Mineral Resources Wuhan 430074 China2. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China3. State Key Laboratory of Continental Dynamics Northwest University Xi’an 710069 China

In the Songpan-Garze fold belt of the northeastern Tibetan Plateau, an Indosinian lithospheric delamination model has been proposed, based on previous investigation of widespread granitoids. However, this model lacks comparable information from volcanism in the area. During the Indosinian delamination in the Songpan-Garze fold belt, whether partial melting of litho- spheric mantle taken place is debated. This paper reports U-Pb zircon LA-ICP-MS ages, geochemical and Sr-Nd-Hf isotopic compositions from the Aba and Wasai calc-alkaline volcanic rocks in the central Songpan-Garze fold belt. Obtained magma crystallization ages are 2.0±3 Ma for the Aba andesite and 2.5±1 Ma for the Wasai andesite. These are consistent with magma crystallization ages of the late Indosinian granitoids in the Songpan-Garze fold belt that formed in a post-collisional tectonic setting. The Aba and Wasai andesites have distinct geochemical singnatures. The former has higher Al2.3, K2., Rb but lower Na2., Ba and Sr contents, suggesting differences in their magmatic evolution. The Aba andesites have ISr values of 0.7070-0.7076 and εNd(t) values of -3.9 to -5.3, and the Wasai andesites have ISr values of 0.7075-0.7077 and εNd(t) values of -3.6 to -3.9. Zircons show εHf(t) values of -3.7 to 0.3 for the Aba andesites and -2.7 to 5.5 for the Wasai andesites. Geochemical and Sr-Nd-Hf isotopic compositions indicate that fractional crystallization and crustal assimilation processes are not key roles for their magma evolution, implying that their chemical compositions are those of primary melts. We suggest that the magma of the Aba andesites originated predominantly from a crustal source, with a minor mantle-derived component. The source region of the magma was likely at the crust-mantle boundary. The magma of the Wasai andesites resulted from partial melting of lithospheric mantle, which was probably metasomatized by fluids so that it was amphibole bearing. The petrogenesis of the Aba and Wasai andesite

关键词： volcanism U-Pb dating geochemistry petrogenesis lithospheric delamination Songpan-Garze fold belt