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Re-Os and U-Pb Geochronology of the Erlihe Pb-Zn Deposit,Qinling Orogenic Belt,Central China,and Constraints on Its Deposit Genesis

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Acta Geologica Sinica(English Edition) 2011年第3期85卷 673-682页

作者： zhang Fan LIU Shuwen LI Qiugen SUN Yali WANG Zongqi YAN Quanren YAN Zhen Key Laboratory of Orogenic Belt and Crustal Evolution Ministry of Education Peking University Beo＇ing 100871 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beo＇ing 10003 7 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

The Erlihe Pb-Zn deposit is an important mine of the Pb-Zn metallogenic zone in the South Qinling *** has been considered a sedimentary exhalative deposit in previous investigations because the ore body occurs concordantly at the transitional location of an upright *** and Os isotopic analyses for paragenetic pyrites with sphalerite and galena from the ore body have been used to determine the timing of mineralization and to trace the source of metallogenic *** Re-Os isotopic data of four pyrite samples construct an isochron,yielding a weighted average age of 226±17 Ma（mean square weighted deviation=1.7）,which is considered the main mineralization age.A dioritic porphyrite vein sample,showing weaker mineralization,was also dated using the SHRIMP zircon UPb isotopic method to constrain the youngest metallogenic age of the ore deposit,because it distributes along a group of tensional joints cutting not only the upright fold in the deposit field,but also the main ore *** dioritic porphyrite sample yields a weighted mean ^（206）Pb/^（238）U age of 221±3 Ma,which is slightly younger than the Re-Os isotopic isochron age of the pyrites,considered as the upper age limit of the mineralization,namely the ending age of the *** Os isotopic compositions of sulfide minerals distribute within a range between Os isotopic compositions of the crust and the mantle, indicating that the ore deposit can be derived from magma-related fluid,and the metallogenic materials are most likely derived from the mixing source of the crust and the *** Erlihe Pb-Zn deposit and associated dioritic porphyrite vein,important records of Qinling tectonic-magmatism-mineralization activities,were formed during the Triassic collisional orogeny processes.

关键词： Erlihe Pb-Zn deposit Re-Os isotopic system dioritic porphyrite vein SHRIMP zircon UPb age Qinling Orogen

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Nitrogen-tailored quasiparticle energy gaps of polyynes

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Chinese Physics B 2022年第12期31卷 170-174页

作者： Kan zhang Jiling Li Peitao Liu Guowei Yang Lei Shi State Key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterGuangzhou Key Laboratory of Flexible Electronic Materials and Wearable DevicesSchool of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Polyyne,an sp~1-hybridized linear allotrope of carbon,has a tunable quasiparticle energy gap,which depends on the terminated chemical ending groups as well as the chain ***,nitrogen doping was utilized to tailor the properties of different kinds of allotrope of ***,how the nitrogen doping tailors the properties of the polyyne remains ***,we applied the GW method to study the quasiparticle energy gaps of the N-doped polyynes with different *** a C atom is substituted by an N atom in a polyyne,the quasiparticle energy gap varies with the substituted position in the *** modification is particularly pronounced when the second-nearest-neighboring carbon atom of a hydrogen atom is *** addition,the nitrogen doping makes the Fermi level closer to the lowest unoccupied molecular orbital,resulting in an n-type *** results suggest another route to tailor the electronic properties of polyyne in addition to the length of polyyne and the terminated chemical ending groups.

关键词： polyyne nitrogen-doping quasiparticle energy gap GW calculations

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Effects of doping FeCl3 on hydrogen storage properties of Li-N-H system

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Progress in Natural Science:Materials International 2017年第1期27卷 139-143页

作者： Weijin zhang Han Wang Hujun Cao Teng He Jianping Guo Guotao Wu Ping Chen Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Materials Research Materials Technology Helmholtz-Zentrum Geesthacht

The effects of doping FeCl3on the LiNH2-2LiH system were investigated systematically. FeCl3was prior to react with LiH during ball milling their mixtures. The metallic Fe, which is generated from metathesis reaction between FeCl3and LiH, plays an important role on improving the dehydrogenation kinetics of LiNH2-2LiH system. The results indicated that the dehydrogenation peak and ending temperatures of the doped 1 mol%FeCl3sample shifted to low temperatures, and the dehydrogenation active energy changed from 102.45 k J/mol to 87.52 k J/mol. While increasing the amount of FeCl3, an excess of LiCl, the by-product of metathesis reaction between FeCl3and Li H, can stabilize LiNH2and thus hinder hydrogen desorption. The dehydrogenation product is a new solid cubic phase solution of lithium imide-chloride. The high limit of the solid solution of LiCl and Li2NH is near the molar ratio of 1:1.

关键词： Hydrogen storage Iron trichloride Lithium amide Reaction kinetics Solid solution Lithium imide-chloride

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Multi-scale temperature variations and their regional differences in China during the Medieval Climate Anomaly

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Journal of Geographical Sciences 2020年第1期30卷 119-130页

作者： HAO Zhixin WU Maowei LIU Yang zhang Xuezhen ZHENG Jingyun Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The Medieval Climate Anomaly(MCA,AD950-1250)is the most recent warm period lasting for several hundred years and is regarded as a reference scenario when studying the impact of and adaptation to global and regional *** this study,we investigated the characteristics of temperature variations on decadal-centennial scales during the MCA for four regions(Northeast,Northwest,Central-east,and Tibetan Plateau)in China,based on high-resolution temperature reconstructions and related warm-cold records from historical *** ensemble empirical mode decomposition method is used to analyze the time *** results showed that for China as a whole,the longest warm period during the last 2000 years occurred in the 10th-13th centuries,although there were multi-decadal cold intervals in the middle to late 12th ***,in the beginning and ending decades,warm peaks and phases on the decadal scale of the MCA for different regions were not consistent with each *** the inter-decadal scale,regional temperature variations were similar from 950 to 1130;moreover,their amplitudes became smaller,and the phases did not agree well from 1130 to *** the multi-decadal to centennial scale,all four regions began to warm in the early 10th century and experienced two cold intervals during the ***,the Northwest and Central-east China were in step with each other while the warm periods in the Northeast China and Tibetan Plateau ended about 40-50 years *** the multi-centennial scale,the mean temperature difference between the MCA and Little Ice Age was significant in Northeast and Central-east China but not in the Northwest China and Tibetan *** to the mean temperature of the 20th century,a comparable warmth in the MCA was found in the Central-east China,but there was a little cooling in Northeast China;meanwhile,there were significantly lower temperatures in Northwest China and Tibetan Plateau.

关键词： China multi-scale variations temperature Medieval Climate Anomaly

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Timing the termination of the Doushantuo negative carbon isotope excursion: evidence from U-Pb ages from the Dengying and Liuchapo formations,South China

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Science Bulletin 2018年第21期63卷 1431-1438页

作者： Mingzhong Zhou Taiyi Luo Warren D.Huff Zhiqing Yang Guanghong Zhou Tian Gan Hua Yang Di zhang School of Geographical and Environmental Sciences Guizhou Normal University State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Department of Geology University of Cincinnati Beijing SHRIMP Center Chinese Academy of Geological Sciences School of Geography and Tourism Guizhou Education University College of Earth Sciences University of Chinese Academy of Sciences

The Doushantuo negative carbon isotope excursion(DOUNCE) is the largest known marine inorganic carbon isotope anomaly. The origin of this pronounced negative excursion is still an enigmatic issue that attracts geologists. Time constraints on the excursion are the critical information that would provide insight into its genesis. In previous decades, the timing of its termination has been constrained by the widely cited zircon U-Pb age of 550.5 ± 0.8 Ma for the tuff at the top of the Miaohe Member at the Jiuqunao section in the Yangtze Gorges area, South China. However, results of recent studies indicate that the reliability of this time constraint needs to be re-evaluated. Here, a geochronological study was carried out using two K-bentonites from Fanglong in South China. A K-bentonite in the lower Dengying Formation yielded a U-Pb age of 557 ± 3 Ma, while a K-bentonite in the basal Liuchapo Formation yielded an age of 550 ± 3 Ma. Based on regional correlations between the Ediacaran successions in South China,the age(557 ± 3 Ma) for the K-bentonite in the lower Dengying Formation may serve as a second critical timing constraint for the ending of the DOUNCE. Combined with available estimates of the DOUNCE duration, our new data indicate that the DOUNCE has a maximum onset age ～570 Ma.

关键词： Doushantuo formation Dengying formation Shuram carbon isotope excursion South China

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Analysis of codon usage patterns in Bupleurum falcatum chloroplast genome

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Chinese Herbal Medicines 2023年第2期15卷 284-290页

作者： Mengqi Gao Xiaowei Huo Liting Lu Mengmeng Liu Gang zhang College of Traditional Chinese Medicine Hebei UniversityBaoding 071002China College of Pharmaceutical Science Institute of Life Science and Green DevelopmentHebei UniversityBaoding 071002China College of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXi’an 712046China

Objective In order to distinguish the traditional Chinese medicine Bupleurum falcatum and its adulterants effectively and develop a better understanding of the factors affecting synonymous codon usage,codon usage patterns of chloroplast genome,we determine the complete chloroplast(cp)genome of *** and clarify the main factors that influence codon usage patterns of 78 genes in *** chloroplast *** The total genomic DNA of fresh leaves from a single individual of *** was extracted with EASYspin plus Total DNA Isolation Kit and 2μg genome DNA was sequenced using Illumina Hiseq 2500 Sequencing *** cp genome of *** was reconstructed with MITObim v1.8 and annotated in the program CPGAVAS2 with default *** script and Codon W were used to calculate the codon usage bias *** The full length of *** cp genome was 155851 bp,132 different genes were annotated in this cp genome containing 80 protein-coding genes,30 tRNA genes,and four rRNA *** codon usage models tended to use A/T-ending *** neutrality plot,ENC plot,PR2-Bias plot and correspondence analysis showed that both compositional constraint under selection and mutation could affect the codon usage models in *** cp ***,three optimal codons were identified and most of these three optimal codons ended with G/*** The cp genome of *** has been characterized and the codon usage bias in *** cp genome is influenced by natural selection,mutation pressure and nucleotide *** results will provide much more barcode information for species discrimination and lay a foundation for future research on codon optimization of exogenous genes,genetic engineering and molecular evolution in ***.

关键词： Bupleurum falcatum L. chloroplast genome codon usage

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Near infra-red light treatment of Alzheimer's disease

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Journal of Innovative Optical Health Sciences 2018年第1期11卷 57-64页

作者： Mengmeng Han Qiyan Wang Xue Wang Yuhui Zeng Yong Huang Qingqiang Meng Jun zhang Xunbin Wei Med-X Research Institute and School of Biomedical Engineering Shanghai Jiao Tong University 1954 Huashan Road Shanghai 200030P.R.China Zhejiang BrainHealth Medical Technology Co.Ltd 332 Wangjiang Road Hangzhou 310002P.R.China Department of Neurosurgery General Hospital of PLA 28 Fuxing Road Beijing 100853 P.R.China

Alzheimers disease(AD)is a chronic neurodegenerative *** symptoms include memoryand spatial learning dificulties,language disorders,and loss of motivation,which get worse overtime,eventually ending in *** ffective treatments are available for AD,*** only attenuate symptoms temporarily and are associated with severe side ***-red(NIR)light has been studied for a long *** investigated the effect of NIR on ADusing a transgenic mouse model,which was obtained by co-injecting two vectors carrying ADmutations in amyloid precursor protein(APP)and presenilin-i(PSEN1)into C57BL/6J *** irradiation equipment consisted of an accommodating box and an LED *** wave-length of NIR light emitted from LED was between 1040 nm and 1090 *** power densitydelivered at the level of the mice was approximately 15 mW/cm^(2),Firstly,we treated the micewith NIR for 40 days,Then,the irradiation was suspended for 28 ***,another 15 daystreatment was brought to *** conducted Morris water maze and immunofluorescenceanalysis to evaluate the effects of *** analysis was based on mea-suring the quantity of plaques in mouse brain slices,Our results show that NIR light improvesmemory and spatial learning ability and reduces plaques *** light represents apotential treatment for AD.

关键词： Alzheimer's disease near infra-red light transgenic mouse model Moris water maze immunofluorescence analysis

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Preparation of MgAl LDHs Intercalated with Amines and Effect on Thermal Behavior for Poly(vinyl chloride)

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Advances in Materials Physics and Chemistry 2014年第12期4卷 258-266页

作者： Xiaoyu Xue Hongmei zhang Shuhua zhang College of Chemistry and Chemical Engineering Shanghai University of Engineering Science Shanghai China

MgAl LDHs intercalated with CO(NH2)2, NH4Cl and NH3·H2O were prepared by co-precipitation and XRD, FT-IR, TGA-DTA and SEM techniques were employed for characterization. The results indicated that the layer-layer spacing of LDHs was enlarged by 0.169, 0.285 and 0.227 Åwith the intercalation of CO(NH2)2, NH+4 and NH3, separately. The effects on thermal stability and degradation behavior of synthesized LDHs where mole ratios of Mg/Al/urea = 3:1:1, Mg/Al/NH4Cl = 3:1:1.5 and Mg/Al/NH3·H2O = 3:1:0.5 were investigated by Congo Red Method and thermogravimetric analysis (TGA) from 25°C - 800°C under N2. The TGA and DTA results showed, by incorporating 5% MgAl-CO(NH2)2 LDH, the dehydrochlorination temperature of PVC composites is 12°C higher than MgAl-NH+4 and MgAl-NH3 LDHs. MgAl-NH3 LDH enhances the ending temperature of the first degradation stage of PVC composites by 8°C compared with MgAl LDH. The LDH intercalated with CO(NH2)2 is proved to be an effective thermal stabilizer for PVC processing.

关键词： Poly(vinyl chloride) Layered Double Hydroxide Thermal Stability

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Comparative Analyses and Phylogenetic Relationships between Cryptomeria fortunei and Related Species Based on Complete Chloroplast Genomes

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Phyton-International Journal of Experimental Botany 2020年第4期89卷 957-986页

作者： Yingting zhang Junjie Yang Zhenhao Guo Jiaxing Mo Jiebing Cui Hailiang Hu Jin Xu Key Laboratory of Forest Genetics&Biotechnology of Ministry of Education Nanjing Forestry UniversityNanjing210037China Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing210037China College of Forestry Nanjing Forestry UniversityNanjing210037China

Cryptomeria fortunei(Chinese cedar)is a highly adaptable woody species and one of the main forest plantation trees in subtropical high-altitude areas in ***,there are few studies on its chloroplast(cp)*** this study,the complete cp genome of *** was sequenced and evaluated via comparative analyses with those of related species(formerly the Taxodiaceae)in *** *** cp genome was 131,580 bp in length,and the GC content of the whole genome was 35.38%.It lost one relevant large inverted repeat and contained 114 unique genes,including 82 protein-coding genes,28 tRNAs and 4 *** relative synonymous codon usage(RSCU)of codons ending with A/U was more than twice that of codons ending with G/*** long repeat structures(LRSs)and 213 simple sequence repeat(SSR)loci were detected in the *** cp *** analyses of 10 cp genomes revealed that substantial rearrangements occurred in the gene ***,6 cp hotspot regions(trnS-GGA,ycf1,trnP-GGG,trnC-GCA,psbZ and accD)were identified,and 4 genes(petL,psbM,rpl22 and psaM)had likely underwent positive *** analysis showed that Cupressaceae,Taxaceae and Cephalotaxaceae clustered to form a clade and that *** was most closely related to ***(Japanese cedar),*** *** Hort and Taxodium distichum(baldcypress).These results provide references for future studies of population genetics,phylogenetic status and molecular markers among Cupressaceae species and for the cultivation of improved varieties.

关键词： Cryptomeria fortunei chloroplast genome comparative analysis phylogenetic analysis

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An Empirical Study on the Intelligibility of Spoken by Chinese University Students

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Chinese Journal of Applied Linguistics 2015年第1期38卷 36-54,128页

作者： zhang Lingli Beijing Foreign Studies UniversityChina University of Geosciences

This paper reports an empirical study on the intelligibility of English spoken by Chinese University students, aiming to identify the factors that hamper intelligibility and suggest the pedagogical priorities in pronunciation teaching. The participants were 45 university sophomores, whose recorded data were transcribed and evaluated correspondingly by 45 educated listeners from 22 different countries. The results reveal that although the speakers＇ English may have strong accents, it is intelligible to international listeners to a great extent. Phonological problems that hamper intelligibility are vowel length and quality, simplification of diphthongs, voiced and voiceless plosives, dental fricative, word ending nasals, consonant clusters as well as stress, rhythm and intonation.

关键词： English as a lingua franca (ELF) intelligibility pronunciation teaching

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