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Ribonucleotide reductase metallocofactor： assembly, maintenance and inhibition

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Frontiers in Biology 2014年第2期9卷 104-113页

作者： Caiguo ZHANG guoqi liu Mingxia HUANG Department of Biochemistry and Molecular Genetics University of Colorado School of Medicine Aurora CO 80045 USA

Ribonucleotide rcductase （RNR） supplies cellular deoxyribonucleotidc triphosphates （dNTP） pools by converting ribonucleotides to the corresponding deoxy forms using radical-based chemistry. Eukaryotic RNR comprises a and β subunits： u contains the catalytic and ailosteric sites; β houses a diferric-tyrosyl radical cofactor （FeⅢ2-Y· ） that is required to initiates nucleotide reduction in α. Cells have evolved multi-layered mechanisms to regulate RNR level and activity in order to maintain the adequate sizes and ratios of their dNTP pools to ensure high- fidelity DNA replication and repair. The central role of RNR in nucleotide metabolism also makes it a proven target of chemotherapeutics. In this review, we discuss recent progress in understanding the function and regulation of eukaryofic RNRs, with a focus on studies revealing the cellular machineries involved in RNR metaUocofactor biosynthesis and its implication in RNR-targeting therapeutics.

关键词： ribonucleotide reductase (RNR) diferric-tyrosyl radical (FeⅢ2-Y·) iron homeostasis

Timing of granite pegmatite-type high-purity quartz deposit in the Eastern Qinling,China:constraints from in-situ LA-ICP-MS trace analyses of quartz and monazite U–Pb dating

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Acta Geochimica 2022年第2期41卷 197-207页

作者： Yong Zhang Haibo Zhao Lei liu Jiayong Pan Likuan Zhu guoqi liu Xiaotian Zhang State Key Laboratory of Nuclear Resources and Environment(East China University of Technology) Nanchang 330013China Zhengzhou Institute of Multipurpose Utilization of Mineral Resources CAGSZhengzhou 450006China Institute of Geological Survey of East China University of Technology Nanchang 330013China Xining Center of Natural Resources Comprehensive Survey CGSXining 810000China

Eastern Qinling,China is one of the important rare metal metallogenic provinces with extensively distributed granite pegmatite *** No.5 granite pegmatite intruded into the granitic gneiss of the Qinling Group,and the major minerals are quartz(39.8%),K-feldspar(18.8%),albite(36.3%),muscovite(3.4%),and garnet(1.1%).Monazite U–Pb isotopic dating indicates that the No.5 pegmatite from the Eastern Qinling was emplaced at ca.420.2±2.2 Ma,which confirms that highpurity quartz mineralization probably formed during the Early ***-situ laser ablation inductively coupled plasma mass spectrometry analysis of quartz show that quartz samples from Eastern Qinling have total trace element concentrations(Al,Ti,Sc,Li,B,Cr,Mn,and Fe)ranging from 23.2 to 52.8 ppm,slightly higher than the quartz(impurity element content from 13.4 to 25.9 ppm)of the Spruce Pine high-purity quartz deposit in western North *** No.5 pegmatite of Eastern Qinling could be defined as one high-purity quartz deposit of China.

关键词： Monazite LA-ICP-MS U-Pb High-purity quartz Granite pegmatite Eastern Qinling

Re–Os and Pb isotope features of pyrite in the Shihangli graphite deposit:implications of coal-generated graphite mineralization in central Hunan,South China

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Acta Geochimica 2023年第5期42卷 895-911页

作者： Yong Zhang Dongsheng Ma Jian-Feng Gao Jiayong Pan Xupeng Lv guoqi liu Fujun Zhong Xiaotian Zhang Ying liu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210046China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Yunnan Institute of Geological Survey Kunming 650032China

The coal metamorphism in Central Hunan pro-vides valuable information about hydrothermal activity and water/rock *** how to collect age data on hydrothermal fluid systems is necessary for understanding the history and genetic mechanisms of large-scale coal-generated graphite *** Shihangli graphite deposit,formed by significant siliceous hydrothermal alteration,is the most distinctive in Central ***–Os dating of pyrite from the Shihangli graphite deposit demonstrates that the coal-generated graphite mineraliza-tion age is-127.6±3.8 *** on in-situ mineral analysis,the hydrothermal pyrite in the Shihangli graphite deposit is mostly enriched in Sb,As,Au,W,Ag,Cu,Pb,and *** on the pyrite Re–Os isochron,the initial(^(187)Os/^(188)Os)values of pyrite were 1.03±0.24 and the Os(t)values varied from 571.8 to *** from the Shihangli graphite deposit comprises a Pb isotope composition similar to that of the Madiyi Formation bulk rock and stibnite from the Xikuangshan Sb *** on the Re–Os,Sr,S,and Pb isotopic compositions of sul-fides in the graphite and Sb deposits in Central Hunan,the Madiyi Formation was likely the primary source of ore-forming elements(Sb,Au,and As).The Re–Os and Pb isotope compositions of pyrite most likely reflect when large-scale fluid migration and coal-generated graphite mineralization occurred in Central Hunan.

关键词： Pyrite Re–Os Pb isotope Graphite Central Hunan

Invasion and defense of the basic social unit in a nonhuman primate society leads to sexual differences in the gut microbiome

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Integrative Zoology 2022年第1期17卷 168-180页

作者： Wancai XIA Mei ZHAO Dali WANG Fan WANG Hua CHEN guoqi liu Lifeng ZHU Dayong LI Key Laboratory of Southwest China Wildlife Resources Conservation(Ministry of Education) China West Normal UniversityNanchongSichuanChina Institute of Rare Animals and Plants China West Normal UniversityNanchongSichuanChina College of Life Sciences Nanjing Normal UniversityNanjingChina Mingkef Biotechnology HangzhouChina

Multilevel society is one of the most complex social systems in natural ecosystems and is a typical feature among some *** the potential connection between social behavior and gut microbiome composition,the multilevel social system could affect the primate gut ***,based on long-term observation(*** unit dynamics,transfer,and behavior),we investigated this potential integrating 16S rRNA gene amplicon sequencing and behavior data in Yunnan snub-nosed monkeys(Rhinopithecus bieti),which possess a multilevel social group based on one male units(OMUs,each unit with several breeding females and their offspring)and all-male unit(AMU,several bachelor males residing together).We found that the mean unweighted Unifrac distance between adult males from different OMUs was significantly lower than that between adult females from different OMUs(paired Wilcoxon test,P=0.007).There was no significant difference in the mean unweighted Unifrac distance between females within the same OMU or between females from different *** findings indicated the potential connection between the defense and invasion of social units and the gut microbiome community in wild Yunnan snub-nosed *** speculated that the resident males of OMUs displaying a significantly higher similarity in the gut microbial community than that of adult females in separate OMUs might be associated with the sexual differences in their interactions and from previously having cohabitated together in the ***,this study suggested that multilevel societies might have an effect on the gut microbial community in this wild nonhuman primate species.

关键词： defense and invasion gut microbial transfer multilevel society sexual differences Yunnan snubnosed monkeys

Effect of KCI on Growth of Carbon Fibers During Carbonization of Phenolic Resin

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China's Refractories 2016年第2期25卷 7-11页

作者： WU Xiaoxian LI Hongxia liu guoqi YANG Wengang MA Tianfei State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research Co.Ltd.LuoyangChina Zhejiang Institute of Geology and Mineral Resources Hangzhou 310007China

Effects of the KCI additions （1%, 3%, 5% and 7% of the phenolic resin mass ） on phase composition and microstructure of the resin carbon and the growth mechanism of carbon fibers were investigated by using commercial liquid phenolic resin as carbon source and micron-scaled KCl us catalyzer, mixing, hexamethylene- tetramine solidification treating, carbon-embedded firing at 1 000 ℃ for 3 h in order to accelerate the graphitization of phenolic resin during carbonization. The results show that the graphitization degree of resin carbon is im- proved by catalysis of KCl, numerous carbon fibers with 30 - 200 nm in diameter and 10 - 20 μm in length and sheet-like carbon in situ grow in resin carbon. The opti- mal addition of KCl is 5% when lots of carbon fibers can be found in resin carbon, and doo2 diffraction peak of graphite appears obviously in the XRD pattern. The growth mechanism of carbon fiber is that the molten KCl at high temperatures absorbs carbonaceous gas from the decomposition of phenolic resin, accelerating the diffu- sion of solid C atoms in liquid KCl ; after the dissolution of C saturates, carbon atoms separate continuously in lo- cal parts to form carbon fibers or flakes ; meanwhile, the concentration gradient formed by local carbon atoms in the melt offers growth drive for the separation of carbon fibers or flakes on KCl surface.

关键词： potassium chloride phenolic resin car-bon fibers catalyzer

Mineral Chemical Characteristics of Gabbro-diorite for Shulouqiu Uranium Deposit in Northern Guangdong, China: Constraint on the Magmatic Source

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 109-110页

作者： ZHONG Fujun PAN Jiayong liu guoqi liu Wenquan QI Jiaming East China University of Technology NangchangJiangxi 330013 Reasearch Institute NO.290 CN NCShaoguanGuangdong 512026

1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in *** deposits are mainly distributing in the Guidong ... 详细信息

关键词： China Constraint on the Magmatic Source Mineral Chemical Characteristics of Gabbro-diorite for Shulouqiu Uranium Deposit in Northern Guangdong

Damage Mechanism and Countermeasures of Carbon Bonded Refractories for Continuous Casting

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China's Refractories 2016年第3期25卷 42-47页

作者： QIAN Fan LI Hongxia liu guoqi YANG Wengang YU Jianbin MA Weikui State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Co.Ltd.

The long nozzle,stopper,and submerged entry nozzle play an important role in continuous casting. They are of the similar composition and are mainly damaged by liquid steel thermal shock which leads to immediate cracks or fracture in their combined area because of the thermal mechanical properties mismatch,or damaged by corrosion on their interface. The failure mechanisms are the thermal shock damage and continuous reaction corrosion. High efficiency and long life of the long nozzle,stopper,and submerged entry nozzle can be realized by optimizing the thermal mechanical properties,the key erosion step,and the combination match.

关键词： long nozzle, stopper, and submerged en-try nozzle for continuous casting thermal shock dam-age continuous reaction corrosion countermeasures

Design of Composite Ladle Shroud for Improving Thermal Shock Resistance

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China's Refractories 2021年第1期30卷 31-34页

作者： liu guoqi LI Hongxia YANG Wengang QIAN Fan YU Jianbin MA Weikui State Key Laboratory of Advanced Refractories Luoyang Institute of Refractories Research Co.Ltd.Luoyang 471039China

A ladle shroud is one of the functional refractories for continuous casting,which undergoes severe thermal shock by molten steel when used without *** composite ladle shroud with an insulating liner presents excellent thermal shock *** element simulation is an effective method to explore the maximum thermal stress for predicting the thermal shock resistance of ladle *** this paper,the influence of the lining materials and the structure of ladle shrouds on the thermal stress distribution is systematically *** working mechanism of the lining material on the body material is also *** materials with low thermal expansion,elastic modulus and thermal conductivity are helpful to improve the thermal shock resistance and an optimum lining thickness is *** lining material can both serve as thermal resistance for the body material to buffer the thermal stress,and apply a strain load to the body material by the thermal strain to increase the stress.

关键词： composite ladle shroud thermal shock resistance finite element simulation thermal stress

Current Situation and Development of Refractories for Clean Steel Production

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China's Refractories 2013年第3期22卷 1-6页

作者： LI Hongxia liu guoqi Sinosteel Luoyang Institute of Refractories Research Co. Ltd

The low cost and high efficient clean steels metallur- gy has been focused much attention in China. Among the factors affecting the cleanliness and consequent quali- ty of steel products, refractories are one of the key fac- tors. Meanwhile the restriction of resource, energy and environment is getting stronger, thus the improvement of refractories becontes much more important. In this paper, refractories selection principle Jbr clean steel production according to their thermodynamic features was ex- plained; refractories for tundLsh and flow control in con- tinuous casting, which play important roles in prohibi- ring secondary contamination of molten steel, were intro- duced. Moreover, new development of low-carbon and carbon-free refractory materials was also described.

关键词： clean steel production basic refractories low-carbon and carbon-free refractories design of re- fractory