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Origin, Evolution and Mechanism of the Jehol Fauna

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 203-215页

作者： Wang Si’en institute of Geology, Chinese Academy of geological sciences, Beijing Liu Linqun institute of Geology Chinese Academy of Geological Sciences Beijing

This paper deals with the geographic distribution and geological setting of the Jehol (northeastHebei-southwest Liaoning-southeast Inner Mongolia) fauna, and discusses the origination and the evolution ofits major biological groups. It is demonstrated that the Yan-Liao (northern Hebei-western Liaoning) area is theprovenance for the fauna. Why the fauna originated and developed in the area was intimately related to suchfactors as the palaeoclimate, palaeogeography, crustal movement, volcanism and frequent reversals of magnet-ic polarity at that time, in addition to the internal factors of the organisms themselves.

关键词： Origin Evolution and Mechanism of the Jehol Fauna

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 10003., China 2 College of Earth sciences, Jilin University, Changchun 13.061, China 3.The geological Laboratory Center and State Key Laboratory of geological Processes and Mineral Resources, China University 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 0.282615 to 0.282657, with εHf(t) values of 5.02±0.28, 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

Simultaneous production of high-frequency synthetic apomixis with high fertility and improved agronomic traits in hybrid rice

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Molecular Plant 2024年第1期17卷 4-7页

作者： Mengqiu Song Wumei Wang Chun Ji Shengnan Li Wei Liu Xiaoyu Hul anhui Feng Shuang Ruan Shiyun Du Huan Wang Kui Dai Longbiao Guo Qian Qian Hongqi Si Xingming Hu College of Agronomy Anhui Agricultural UniversityHefeiAnhui 230036China State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhouZhejiang 310006China Rice Research institute Anhui Academy of Agricultural SciencesHefeiAnhui 230031China Jiangxi Modern Seed Industry Co.NanchangJiangxi 330026China

Dear Editor,Utilization of heterosis is fundamental to modern agricultural improvement and contributes significantly to food security and agricultural development(Ouyang et al.,2022).However,heterosis of F,hybrids cannot be stably ***,or asexual reproduction through seeds,offers the potential for the fixation of heterosis in F,hybrids and the formation of clonal offspring,which could have considerable implications for plant breeding and agriculture(Schmidt,2020).But naturally occurring apomixis has never been found in major ***,synthetic apomixis has been successfully generated by inducing incomplete meiotic development combined with parthenogenesis development to produce cloned rice(Oryza sativa)seeds(Khanday et al.,2019;Wang et al.,2019;Vernet et al.,2022;Wei et al.,2023..

关键词： sativa fertility breeding

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science China Earth sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth sciences and Natural Resources, China University of Geosciences, Beijing 100083. China 2. Faculty of Earth sciences, China University of Geosciences, Wuhan 43.074, China 3. Beijing SHRIMP Center, institute of Geology, Chinese Academy of geological sciences, Beijing 10003., China 1. Faculty of Earth sciences and Natural Resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China 3. Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2468 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Chemical composition and size distribution of secondary organic aerosol formed from the photooxidation of isoprene

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Journal of Environmental sciences 2009年第11期21卷 1525-1531页

作者： LIU Xianyun, ZHANG Weijun, WANG Zhenya, ZHAO Weixiong, TAO Ling, YANG Xibin Laboratory of Environmental Spectroscopy, anhui institute of Optics and Fine Mechanics, Chinese Academy of sciences, {3. 23.03., China. [a]Laboratory of Environmental Spectroscopy Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China

Photooxidation of isoprene leads to the formation of secondary organic aerosol （SOA）. In this study, the chemical composition of SOA formed from OH-initiated photooxidation of isoprene has been investigated with gas chromatography/mass spectrometry （GC/MS） and a home-made aerosol time-of-fiight mass spectrometer. Sampling particles generated in a home-made smog chamber. The size distribution of SOA particles was detected by a TSI 3.21 aerodynamic particle size spectrometer in real time. Results showed that SOA created by isoprene photooxidation was predominantly in the form of fine particles, which have diameters less than 2.5 μm. The obtained mass spectra of individual particles show that products of the OH-initiated oxidation of isoprene contain methyl vinyl ketone, methacrolein, formaldehyde, and some other hydroxycarbonyls. The possible reaction mechanisms leading to these products were also discussed.

关键词： secondary organic aerosols isoprene aerosol time-of-fiight mass spectrometer smog chamber size distribution

A Genetic Model for Ore Magma of the Chibaisong Copper-Nickel Sulphide Deposit, Jilin

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Acta Geologica Sinica(English Edition) 1994年第4期68卷 401-416页

作者： Fu DebinJilin institute of geological sciences, Changchun, Jilin Fei Zhenbi Jilin institute of geological sciences Changchun Jilin

In the early 1980's, the author proposed his view that copper-nickel sulphide deposts are of ore magma origin. For more than ten years, this view has aroused attention of his colleagues at home and abroad. In this paper an attempt is made to deal with the genetic model for ore magma of copper-nickel sulphide deposits in more details on the basis of geological, geochemical, petrophysico - chemical and thermodynamic studies of the Chibaisong copper-nickel sulphide deposit in the Changbai Mountains, Jilin province.

关键词： Chibaisong Changbai Mountains copper-nickel deposit genetic model of ore magma

Kaolin Deposits of Weathering-Residual in the Coastal Area of Guangdong Province

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 289-305,340页

作者： Zhou Guoping Lin Yuchuan institute of Mineral Deposits, Chinese Academy of geological sciences, Beijing,Center of geological Analysis of Guangdong Province, Guangzhou institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

Kaolin deposits of weathering-residual type make up a large proportion in different types of kaolin depos-its and are widely used in ceramics, electron ceramics, rubber and paper industries. This paper discusses sys-tematically this type of kaolin deposit with respect to their features of occurrence, mineralogical and chemicalcomposition and transformation of minerals during supergene processes, thus providing some basic data forthe rational exploitation and utilization of the kaolin resources.

关键词： Kaolin Deposits of Weathering-Residual in the Coastal Area of Guangdong Province

Mineralogy and Mode of Occurrence of Gold, Silver and Bismuth of the Caijiaying Lead-Zine-Silver Deposit, Hebei Province

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 371-385,461页

作者： Huang Dianhao Ding Xiaoshi Wu Chengyu Zhang Changjiang institute of Mineral Deposits, Chinese Academy of geological sciences, Beijing geological Party No.3. Hebei Bureau of Geology and Mineral Resources, Zhang jiakou, Hebei Fei Zhenbi institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

The deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. These metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2Te. They are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold.

关键词： Mineralogy and Mode of Occurrence of Gold Hebei Province

REE Geochemistry of Skarns in the Tongshan Copper Deposit, Guichi, anhui Province

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Acta Geologica Sinica(English Edition) 1987年第1期 105-115页

作者： Qiu Ruilong anhui institute of geological {3., He fei

This paper presents REE abundance pattern and REE geochemistry of granodiorite porphyry, skarns, as well as late hydrothermal alterations in the Tongshan copper deposit, Guichi County and, in the light of their similarities and variations, deals with the genesis of the skarns and the transformation process of the post-skarn hydrothermal alterations. On such a basis, the inference is drawn that the skarn-forming solution was produced by further fractionation of residual magma, thus belonging to a transitional fluid between residual magma and hydrothermal solution which, with the continuous variation of its components during the metasomatism, tended to become a hydrothermal solution.

关键词： REE Geochemistry of Skarns in the Tongshan Copper Deposit Guichi anhui Province