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Provenance of upper Permian-lowermost Triassic sandstones, Wutonggou low-order cycle, Bogda Mountains, NW China:implications on the unroofing history of the Eastern North Tianshan Suture

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Journal of Palaeogeography 2020年第3期9卷 314-334页

作者： dong-yu zheng Wan Yang Geology and Geophysics Program Missouri University of Science and TechnologyRollaMO 65409USA

This study investigates the provenance of sedimentary rocks in Bogda Mountains, NW China, and reconstructs the lithology and unroofing history of the Eastern North Tianshan Suture. Petrographic point counting data of sandstones and compositions of conglomerates of upper Permian-lowermost Triassic Wutonggou low-order cycle from Zhaobishan, North Tarlong, Taodonggou, and Dalongkou sections in the southern and northern foothills of Bogda Mountains were used to interpret the temporal and spatial variations of lithology of the Eastern North Tianshan Suture, which is the sediment source area. Three compositional trends were identified. A trend of upwardincreasing quartz content and granitic pebbles in Zhaobishan section suggests a change from the undissected volcanic arc, accretionary wedge and trench setting to predominantly transitional volcanic arc and subordinate accretionary wedge and trench, in the eastern part of the Eastern North Tianshan Suture. In North Tarlong and Taodonggou sections, however, the lithic content decreases and the contents of quartz and granitic pebbles increase up sections. These trends indicate that the western part of the Eastern North Tianshan Suture changed from an undissected volcanic arc to the transitional volcanic arc, accretionary wedge and trench. No clear trend in the lithic-rich sandstones of the Dalongkou section indicates that sediments were derived from the undissected volcanic arc in the Eastern North Tianshan Suture and local rift shoulders. Compositional variations of studied rocks suggest that the Eastern North Tianshan Suture was an amalgamated complex with great spatial and temporal heterogeneities in lithology and experienced persistent unroofing during late Permian-earliest Triassic. This study reconstructs a key element of the Chinese Tianshan Suture and serves as an example to understand the unroofing processes of ancient sutures.

关键词： Provenance Wutonggou low-order cycle Bogda Mountains Unroofing Eastern North Tianshan Suture NW China

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Preparation of Cr_2O_3 precursors by hydrothermal reduction in the abundant Na_2CO_3 and Na_2CrO_4 solution

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International Journal of Minerals,Metallurgy and Materials 2012年第11期19卷 978-985页

作者： Guang-ye Wei Jing-kui Qu yu-dong zheng Tao Qi Qiang Guo School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Beijing 100190 China Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

Precursors of chromium oxide （p-Cr203） were prepared by reducing hexavalent chromium in the presence of sodium carbonate solution under hydrothermal conditions. Methanal was used as the reductant, and carbon dioxide was the acidulating agent. The influences of reaction temperature, initial pressure of carbon dioxide, isothermal time and methanal coefficient on Cr（VI） reduction were investigated. Ex- perimental results showed that Cr（VI） was reduced to Cr（III） with a yield of 99%. Chemical titration, thermogravimetry （TG）, X-ray diffrac- tion （XRD） analysis, and scanning electron microscopy （SEM） were used to characterize the p-Cr203 and Cr203. The series of p-Cr203 were found to be multiphase even if they presented different colors, from gray green to lavender. After these p-Cr203 samples were calcined, the product of rhombohedral Cr203 with a purity of 99.5wt% was obtained.

关键词： chromium oxide hydrothermal reduction sodium carbonate methanal laterite ores

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Comparative Genomic Analysis of Gene Variations of Two Chinese Yersinia pestis Isolates from Vaccine Strain EV76

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Biomedical and Environmental Sciences 2012年第4期25卷 440-448页

作者： YOU yuan Hai WANG Peng WANG Yan Hua ZHANG Mao Jun SONG Zhi Zhong HAl Rong yu dong zheng WANG Hai Bin dong Xing Qi ZHANG Jian Zhong State key Laboratory for Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Provincial Key Laboratory for Plague Control and Prevention Yunnan Institute for Endemic Diseases Control and PreventionDali 671000YunnanChina

Objective To investigate genomic variations of two Chinese Yersinia pestis isolates that were isolated from different plague foci obtained from vaccine strain EV76 from the yunnan province of China. Methods A microarray containing 12 000 probes covering the entire genome of seven Yersinie pestis and two Yersinia pseudotuberculosis strains, was used. PCR assays were performed to confirm microarray results. Results The gene variations detected included the absence of five genes related to the synthesis of betaine in both EV76 and another sequenced attenuated strain, KIM D27. Several genes related to phage-related membrane proteins were found to be absent in the Antiqua biovar yunnan strain, 485, which was isolated from a rodent plague foci. Conclusion These findings provide initial insight into the distinct strains isolated from natural foci, within their genomic context, including yunnan Y. pestis strains. This information will be used therefore to establish subsequent comparisons of these sequences with published complete genomes of other strains.

关键词： arrayCGH Yersinia pestis

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Ethanol Metabolism in Calluses of Several Selected Plant Species on Two Typical Plant-Growth-Regulator Balanced Media

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Wuhan University Journal of Natural Sciences 2000年第4期5卷 500-504页

作者： Yang yue-sheng, zheng Ying-dong, Chen yu-fen, zheng Ling College of Biotechnology, South China Agricultural University, Guangzhou 510642, China College of Biotechnology South China Agricultural University Guangzhou China

For investigation on the characteristics of ethanol metabolism in tissues of different plant species, calluses from eight selected plant species were cultured on medium supplemented with ethanol in tightly sealed culture flasks. Changes of the ethanol level were detected by gas chromatography. During the culture period, the calluses of tobacco, potato and petunia were, able to catabolize exogenous ethanol, resulting in the prominent decline of the ethanol level in the medium. The calluses of melon and peanut were also able to catabolize thanol but with lower efficiency. The other three calluses of carrot, soybean and rice did not catabolize ethanol but instead produced small to large amount of ethanol, resulting in the increase of the ethanol level in the media. It was also found that changing the balance between auxin and cytokinin could influence only the ethanol metabolism efficiency but could not change the metabolism patterns on ethanol of the cultured calluses. It can be concluded that, ethanol metabolism pattern of calluses in cultures is an innate physiological characteristic of the respective plant species.

关键词： callus culture ethanol metabolism plant growth regulator plant physiology

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Screening of Genes with Unique Mutations of Microcus

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Biomedical and Environmental Sciences 2013年第9期26卷 778-781页

作者： SHEN Xiao Na XIA Lian Xu HAI Rong LIANG Ying XU dong Lei CAI Hong WANG yu Meng zheng Xiao WANG Yan Hua ZHANG Zhi Kai WEI Jian Chun FU Xiu Ping ZHANG En Min ZHANG Hui Juan yu dong zheng State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and Prevention

Yersinia pestis is the causative agent of bubonic and pneumonic plagues. Strains of Y. pestis are classified into four biovars： antiqua, mediaevalis, orientalis, and microtus[11. There are two microtus-related plague loci in China： the Microtus brandti plague focus in the Xilin Gol Grassland （focus L） and the Microtus fuscus plague focus in the Ojnghai-Tibet Plateau （focus M）.

关键词： Screening of Genes with Unique Mutations of Microcus gene

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Assessment of Comparative Genomic Hybridization Experiment by an in situ Synthesized CombiMatrix Microarray with Yersinia pestis Vaccine Strain EV76 DNA

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Biomedical and Environmental Sciences 2010年第5期23卷 384-390页

作者： yuAN-HAI YOU PENG WANG YAN-HUA WANG HAI-BIN WANG dong-zheng yu RONG HAI JIAN-ZHONG ZHANG National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China

Objective The quality of microarray data influences the accuracy of comparative genomic analyses to a large *** ensure that the results obtained by using an in situ synthesized microarray are accurate,data quality is to be assessed by evaluating the melting temperature (Tm) of probes,probability of false synthesis rates,and fragmentation of labeled *** DNA from the Yersinia pestis vaccine strain EV76 was used for microarray *** results were confirmed by *** and bioinformatics methods were employed to perform microarray data analyses and *** Correlation coefficients of the three datasets were above 0.95 after two-time stripping and hybridization with a labeled DNA with the size of fragmentation being 200 bp-2 kb,which showed that the hybridization results were highly *** coefficients were lower with the values ranging from 0.87 to 0.92 between the datasets generated from hybridization with different sizes of the labeled DNA *** the relationship between Tm and signal intensity,there was a different distribution of Tm in the lowest 300 or 3 000 probes with a range of 70 ℃-72 ℃ and the highest 300 or 3 000 probes with a range of 72 ℃-74 ℃.Conclusion The results of this study suggest that the initial microarray design may affect the accuracy of final analyses and that the probe Tm and the size of the labeled fragment may be the two factors of the greatest importance.

关键词： Array CGH Data quality Assessment

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Dispersion of Soluble Matters in Newton-dipolar Stratified Fluid and Effects of Peripheral Layer

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 236-241页

作者： Zhangji LU, Shousheng dong, yu SHEN and Guangping zheng (Department of Mechanics and Engineering Science, Fudan University, Shanghai 200433,China)(Department of Physics, East China Normal University, Shanghai 200062, China) Dept. of Mechanics and Eng. Science Fudan University Shanghai 200433 China Department of Physics East China Normal University Shanghai 200062 China

In the paper, the dispersion law and the concentration distributions of soluble matters in Newton-dipolar fluids flowing through a circular tube have been investigated. Main results are: (1) for the dependence of M on A (or H), the completely opposite trends are obtained in the cases with and without the peripheral layer. (2) effects of δ on　M have the minimum values near 8=0.85-0.9. (3) various models such as couple stress,micropolar, dipolar, Newton-newtonian, Newton-couple stress and Newton-micropolar　model etc. are all special cases of Newton-dipolar fluid (where Mz=0). WhenMz≠ 0,however, there are evident differences between the Newton-dipolar fluid and the Newtoncouple stress fluid, the Newton-micropolar fluid.

关键词： dipolar fluid dispersion effects of a peripheral layer tube flow of complex fluid

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