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Storage,pattern and driving factors of soil organic carbon in the desert rangelands of northern Xinjiang,north-west China

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Frontiers of Earth Science 2024年第3期18卷 598-610页

作者： Huixia LIU Zongjiu SUN Yuxuan CUI Yiqiang DONG Panxing HE Shazhou AN xianhua zhang College of Grassland Sciences Xinjiang Agricultural UniversityUrumqi 830052China Ministry of Education Key Laboratory for Western Arid Region Grassland Resources and Ecology Urumqi 830052China Xinjiang Key Laboratory of Grassland Resources and Ecology Urumqi 830052China

Soil organic carbon(SOC)is a critical variable used to determine the carbon ***,large uncertainties arise when predicting the SOC stock in soil profiles in Chinese grasslands,especially on desert *** studies have shown that desert ecosystems may be potential carbon sinks under global climate *** of the high spatial heterogeneity,time-consuming sampling methods,and difficult acquisition process,the relationships the SOC storage and distribution have with driving factors in desert rangelands remain poorly ***,we investigated and developed an SOC database from 3162 soil samples(collected at depths of 0−10 cm and 10−20 cm)across 527 sites,as well as the climate conditions,vegetation types,and edaphic factors associated with the sampling sites in the desert rangelands of northern Xinjiang,north-west *** study aims to determine the SOC magnitude and drivers in desert *** findings demonstrate that the SOC and SOC density(SOCD)were 0.05−37.13 g·kg^(-1)and 19.23−9740.62 g·m^(-2),respectively,with average values of 6.81±5.31 g·kg^(-1)and 1670.38±1202.52 g·m^(-2),*** spatial distributions of SOC and SOCD all showed gradually decreasing trends from south-west to ***-SOC areas were mainly distributed in the piedmont lowlands of the Ili valley,while low-SOC regions were mainly concentrated in the north-west area of *** redundancy analysis results revealed that all environmental factors accounted for approximately 37.6%of the spatial variability in SOC;climate factors,vegetation factors,and soil properties explained 15.0%,1.7%,and 12.3%,*** structural equation model(SEM)further indicated that evapotranspiration,average annual precipitation,and the SWC were the dominant factors affecting SOC accumulation,mainly through direct effects,although indirect effects were also delivered by the vegetation *** together,the results obtained herein updated the SOC data pool

关键词： soil organic carbon desert rangeland SEM analysis driving factors Xinjiang Uygur Autonomous Region of China

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Conversion of syngas to methanol and DME on highly selective Pd/ZnAl_(2)O_(4) catalyst

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Journal of Energy Chemistry 2021年第7期30卷 564-572页

作者： Liang Liu Zenan Lin Shanya Lin Yeyun Chen Lina zhang Shaopeng Chen xianhua zhang Jingdong Lin Zhaoxia zhang Shaolong Wan Yong Wang College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005FujianChina National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters Xiamen UniversityXiamen 361005FujianChina Voiland School of Chemical Engineering and Bioengineering Washington State UniversityPullmanWA99164United States

Supported Pd catalysts with varied Pd loadings(x=0.5 wt%, 2.0 wt%, 5.0 wt%, 7.5 wt%, 15.0 wt%) were prepared by the incipient wetness impregnation method using a ZnAl_(2)O_(4) spinel *** found that ZnAl_(2)O_(4) supported Pd catalysts with low Pd loadings(e.g., 0.5 wt%) are very selective in syngas conversion to methanol and dimethyl-ether(DME).XRD and TEM characterization shows that,after reduction at350℃,PdZnβ phase with Pd:Zn molar ratio of 1:1 is favored to form predominantly on the spinel support at relatively low Pd loadings,*** than 5.0 wt%, while Pd-rich PdZnα alloy phase exists at Pd loadings above 5.0 wt%.A higher reduction temperature such as 500℃ can facilitate the transformation from PdZnα to PdZnβ phase in those catalysts with high Pd *** further found that catalysts with predominant PdZnβ phase are selective in the methanol and DME production from syngas,while the presence of PdZnα phase leads to the notable formation of alkanes byproducts,resulting in reduced methanol and DME *** formation from dehydration of methanol depends on the acidity of catalysts,which was found to increase with Pd loading,probably due to the formation of isolated Al_(2)O_(3) as a result of Zn migrating from ZnAl_(2)O_(4) spinel phase to form the PdZn phases with Pd.

关键词： Pd/ZnAl_(2)O_(4) Syngas Methanol Dimethyl ether

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Chemical looping oxidative propane dehydrogenation controlled by oxygen bulk diffusion over FeVO_(4)oxygen carrier pellets

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Chinese Journal of Chemical Engineering 2023年第1期53卷 409-420页

作者： Hongbo Song Wei Wang Jiachen Sun Xianhui Wang xianhua zhang Sai Chen Chunlei Pei Zhi-Jian Zhao Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China Department of Chemistry National University of Singapore3 Science Drive 3117543Singapore

The oxygen distribution and evolution within the oxygen carrier exert significant influence on chemical looping *** paper describes the influence of oxygen bulk diffusion within FeVO4 oxygen carrier pellets on the chemical looping oxidative propane dehydrogenation(CL-ODH).During CL-ODH,the oxygen concentration at the pellet surface initially decreased and then maintained stable before the final *** the stage with the stable surface oxygen concentration,the reaction showed a stable C3H6 formation rate and high C3H6 ***,based on Fick’s second law,the oxygen distribution and evolution in the oxygen carrier at this stage were further *** was found that main reactions of selective oxidation and over-oxidation were controlled by the oxygen bulk diffusion.C3H8 conversion rate kept decreasing during this stage due to the decrease of the oxygen flux caused by the decline of oxygen gradient within the oxygen carrier,while C3H6 selectivity increased due to the decrease of *** addition,reaction rates could increase with the propane partial pressure due to the increase of the oxygen gradient within the oxygen carrier until the bulk transfer reached its limit at higher propane partial *** study provides fundamental insights for the diffusion-controlled chemical looping reactions.

关键词： Chemical looping Diffusion Reaction kinetics Oxygen carriers Oxidation

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Secure communication by generalized chaotic synchronization

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Journal of University of Science and Technology Beijing 2003年第2期10卷 75-78页

作者： Lequan Min, xianhua zhang, and Miao YangApplied Science School, University of Science and Technology Beijing, Beijing 100083, China Applied Science School University of Science and Technology Beijing Beijing 100083 China

Chaotic communication is a rather new and active field of research. Althoughit is expected to have promising advantages, some investigators provide evidences that chaoticcommunication is not safety. This letter provides a new chaotic secure communication scheme based ona generalized synchronization theory of coupled system. The secret message hidden in the chaoticsource signal generated via the scheme is very difficult to be unmasked by so-called nonlineardynamic forecasting technique. One example for Internet communications was presented to illustratethe security of our scheme.

关键词： secure communication generalized chaotic synchronization Internet

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Glycolysis regulates gene expression by promoting the crosstalk between H3K4 trimethylation and H3K14 acetylation in Saccharomyces cerevisiae

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Journal of Genetics and Genomics 2019年第12期46卷 561-574页

作者： Yinsheng Wu Shihao zhang Xuanyunjing Gong Qi Yu Yuan zhang Mingdan Luo xianhua zhang Jerry L.Workman Xilan Yu Shanshan Li State Key Laboratory of Biocatalysis and Enzyme Engineering College of Life SciencesHubei UniversityWuhanHubei430062China Stowers Institute for Medical Research 1000 E.50th StreetKansas CityMO64110USA

Cells need to coordinate gene expression with their metabolic states to maintain cell homeostasis and ***,how cells transduce nutrient availability to appropriate gene expression response via histone modifications remains largely ***,we report that glucose specifically induces histone H3K4 trimethylation(H3K4me3),an evolutionarily conserved histone covalent modification associated with active gene transcription,and that glycolytic enzymes and metabolites are required for this in?*** glycolysis supplies S-adenosylmethionine for histone methyltransferase Setl to catalyze H3K4me3,glucose induces H3K4me3 primarily by inhibiting histone demethylase Jhd2-catalyzed H3K4 *** provides acetyl-CoA to stimulate histone acetyltransferase Gcn5 to acetylate H3K14,which then inhibits the binding of Jhd2 to chromatin to increase *** repressing Jhd2-mediated H3K4 demethylation,glycolytic enzymes regulate gene expression and cell survival during chronological ***,our results elucidate how cells reprogram their gene expression programs in response to glucose availability via histone modifications.

关键词： Gene transcription Glycolysis Histone modifications Yeast H3K4me3 H3K14ac

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Pharmacokinetic and pharmacodynamic study of DCH extract after oral administration

Pharmacokinetic and pharmacodynamic study of DCH extract aft...

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第二届国际抑郁共病暨第十二届中国中西医结合基础理论学术研讨会

作者： zhang xianhua Huang Xi Department of Clinical Pharmacology Xiangya HospitalCentral South University Institute of Clinical Pharmacology Central South University

In current study,a sensitive and selective liquid chromatography-tandem mass spectrometry method was developed to quantitatively determine 5 bioactive compounds(tanshinol,ferulic acid,protocatechuic acid,rosmarinic acid,salvianolic acid B) in rat plasma and qualitative detect multi-components in rat hippocampus,prefrontal cortex,and cerebrospinal fluid(CSF)simultaneously following oral administration of DCH extract(20 g/kg).This investigation was also designed to verify the expected preventive effect of cerebral ischemia injury after oral administration of DCH *** separation was carried out on an 300 SB-C18 column using a gradient elution with a mobile phase composed of acetonitrile-water(containing0.1%formic acid) at a flow rate of 1.0 mL/*** mass spectrometry(MS) determination was conducted in the multiple reaction monitoring(MRM) mode with negative electrospray *** validated method exhibited good linearity with correlation coefficients greater than 0.9949 over a wide concentration range and the lower limits of quantification were 2.09-12.2 ng/ml for the 5 *** assay was successfully applied to investigate the pharmacokinetics of 5 compounds in rat plasma after oral administration of DCH *** pharmacodynamics study,the result of neurological deficit and infarct volume suggested DCH extracts could exert the preventive effect in cerebral ischemia injury.

关键词： DCH extracts pharmacokinetic LC/MS/MS pharmacodynamic cerebral ischemia injury

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Comparative DNA-methylome and transcriptome analysis reveals heterosis-and polyploidy-associated epigenetic changes in rice

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The Crop Journal 2023年第2期11卷 427-437页

作者： Xiaolan Rao Jun Ren Wei Wang Rongrong Chen Qian Xie Yanqing Xu Dongmei Li Zhaojian Song Yuchi He Detian Cai Pingfang Yang Shiyou Lyu Li Li Wei Liu xianhua zhang School of Life Sciences Hubei UniversityWuhan 430062HubeiChina Wuhan Polyploid Bio-Technology Limited Company Wuhan 430345HubeiChina State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research CenterChangsha 410125HunanChina Institute for Regenerative Medicine Shanghai East HospitalSchool of Life Sciences and TechnologyTongji UniversityShanghai 200123China

Heterosis and polyploidy have an overwhelming influence on plant ***,polyploid rice hybrids have been used to breed new rice varieties because they combine the advantages of both heterosis and *** this study,we generated six rice lines:autotetraploid rice hybrids and their autotetraploid parents,diploid donors,and hybrids of the diploid *** investigate the molecular mechanism controlling the effects of both hybridization and polyploidization,we performed bisulfite and RNA sequencing on young panicles at the pollen meiosis stage to compare the DNA metabolomes and transcriptomes among the six rice *** hybrids lines were hypermethylated compared to their corresponding parents and the autotetraploid lines showed globally increased DNA methylation of their transposable elements compared to the diploid *** alteration in DNA methylation level corresponded to the differential gene expressions among the rice genotypes,suggesting that methylation changes induced by polyploidization and hybridization may affect gene *** of gene candidates were identified that may be associated with heterosis and *** results provide DNA information that can be used to investigate epigenetic modification during heterosis and polyploidy in rice.

关键词： Oryza sativa Neotetraploid rice Heterosis Whole genome duplication Epigenetic changes

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La-doped Pt/TiO_2 as an efficient catalyst for room temperature oxidation of low concentration HCHO

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Chinese Journal of Catalysis 2017年第1期38卷 39-47页

作者： Honggen Peng Jiawei Ying Jingyan zhang xianhua zhang Cheng Peng Cheng Rao Wenming Liu Ning zhang Xiang Wang Institute of Applied Chemistry College of Chemistry Nanchang University Nanchang 330031 Jiangxi China School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China

Catalytic oxidation of formaldehyde (HCHO) is the most efficient way to purify indoor air of HCHO pollutant. This work investigated rare earth La‐doped Pt/TiO2 for low concentration HCHO oxidation at room temperature. La‐doped Pt/TiO2 had a dramatically promoted catalytic performance for HCHO oxidation. The reasons for the La promotion effect were investigated by N2 adsorption, X‐raydiffraction, CO chemisorption, X‐ray photoelectron spectroscopy, transmission electron microscopy(TEM) and high‐angle annular dark field scanning TEM. The Pt nanoparticle size was reduced to 1.7nm from 2.2 nm after modification by La, which led to higher Pt dispersion, more exposed activesites and enhanced metal‐support interaction. Thus a superior activity for indoor low concentrationHCHO oxidation was obtained. Moreover, the La‐doped TiO2 can be wash‐coated on a cordieritemonolith so that very low amounts of Pt (0.01 wt%) can be used. The catalyst was evaluated in asimulated indoor HCHO elimination environment and displayed high purifying efficiency and *** can be potentially used as a commercial catalyst for indoor HCHO elimination.

关键词： Low‐concentration formaldehyde Room‐temperature oxidation Rare earth Lanthanum doping Platinum Titania Monolithic catalyst

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Zigzag emitting array synthesis aperture acoustical holography

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Chinese Journal of Acoustics 1992年第1期11卷 76-83页

作者： XIA xianhua and zhang Dejun(Wuhan Institute of Physics, Academia Sinica, Wuhan, 430071 )

Zigzag Emitting Array Synthesis Aperture ( ZEASA ), a new model of the acoustical imaging is presented and discussed in the paper. The imaging system of this model has not only enough emitting energy for underwater acoustical imaging but also a large field of view. Its scanning speed is high and its cost is relatively low. The form of the point spread function of the system is given. It is found that if the system parameters are controlled properly, the major lobe of the point spread function is similar to that of the system with a square receiving array, and the side lobes along the axis direction of the linear receiving array are lowered. An imaging system with a 64-element. linear receiving array and a 64-element zigzag emitting array is simulated and the analysis of ZEASA is proved to be correct by the results of the simulation.

关键词： Zigzag emitting array synthesis aperture acoustical holography

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A Case of Acute Upper Gastrointestinal Bleeding in Liver Cirrhosis Complicated by Acute Cerebral Infarction and Acute Myelitis

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Journal of Biosciences and Medicines 2023年第5期11卷 303-309页

作者： Xiaohui Liao Tengteng Xu xianhua zhang Xianliang Mi Changqing Yang Zibai Wei Department of Gastroenterology Heping Hospital Affiliated to Changzhi Medical College Changzhi China

Background: Acute upper gastrointestinal bleeding in liver cirrhosis combined with acute cerebral infarction is uncommon in clinical work, and then combined with acute myelitis is even rarer and more complex, which poses a greater challenge to clinical diagnosis and treatment. This paper reports a case of acute upper gastrointestinal bleeding in liver cirrhosis complicated by acute cerebral infarction and acute myelitis, which be hoped to provide a reference for clinical work. Methods: We retrospectively evaluated the clinical information of a 68-year-old female admitted to the Digestive Medical Department with acute gastrointestinal bleeding and appeared limb movement disorder on the third day. Results: The patient was eventually diagnosed with acute upper gastrointestinal bleeding in liver cirrhosis complicated by acute cerebral infarction and acute myelitis. Conclusions: When patients with liver cirrhosis have abnormal neurological symptoms, in addition to liver cirrhosis-related complications, doctors need to consider cerebrovascular diseases and myelitis.

关键词： Liver Cirrhosis Upper Gastrointestinal Bleeding Acute Cerebral Infarction Acute Myelitis

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