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Soil microbial community diversity and distribution characteristics under three vegetation types in the Qilian Mountains, China

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Journal of Arid Land 2023年第3期15卷 359-376页

作者： TONG Shan CAO Guangchao ZHANG zhuo ZHANG Jinhu yan Xin Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal UniversityXining 810008China Qinghai Province Key Laboratory of Physical Geography and Environmental Process College of Geographical ScienceQinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability People's Government of Qinghai Province and Beijing Normal UniversityXining 810008China

Qilian Mountains in Northwest China is a significant ecological security barrier due to its distinctive geographic setting,which has significant biological resource and gene *** order to assess the soil quality and ecosystem health in this area,we identified the structural characteristics and functional groups of soil microbial *** study focused on Amidongsuo,a typical watershed of the Qilian Mountains,and researched the vertical distribution and dominant populations of soil microorganisms in different habitats,and the relationship between soil microorganisms and environmental *** microorganisms from three grassland plots,five shrubland plots,and five forest plots in Amidongsuo were studied using high-throughput *** Venn diagram showed that the types of bacteria were fewer than those of fungi in *** bacteria Acidobacteriota,Proteobacteria,and Methylomirabilota as well as fungi Basidiomycota,Ascomycota,and Mortierellomycota played dominant roles in Amidongsuo,according to the LEfSe(linear discriminant analysis(LDA)effect size)and community structure *** to the ANOSIM(analysis of similarities)result,for both bacteria and fungi,R values of grassland and shrubland were small(R^(2)=0.045 and R^(2)=0.256,respectively),indicating little difference between these two ***(redundancy analysis)showed a closer relationship between soil nutrients and fungi,and a gradually decreasing correlation between soil nutrients and microorganisms with increasing soil *** were mainly affected by pH,nitrogen(N),and potassium(K),while fungi were mainly affected by ***,fungi had more effect on soil quality than ***,adjustment of soil K content might improve the soil environment of Amidongsuo in the Qilian Mountains.

关键词： fungi bacteria diversity soil nutrient Qilian Mountains

Razumikhin Type Boundedness Theorems in Terms of Two Measures for Impulsive Integro-differential Systems

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 1007-1016页

作者： zhuo-ying L yan-Lin ZHENG Lai-liang ZHANG Depart of Common Courses Shandong University of Science and Technology Faculty of Science Shandong University of Science and Technology

Some new direct criteria of boundedness in terms of two measures for impulsive integro-differential systems with fixed moments of impulse effects are established by Lyapunov functions coupled with Razumikhin techniques.

关键词： impulsive integro-differential system Lyapunov function boundedness in terms of two measures

Orientation Dependence of the Micro-Pillar Compression Strength in an Electron Beam Melted Ti-6Al-4V Alloy

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 476-484页

作者： Jinsen Tian Jiang Ma Ming yan zhuo Chen Jun Shen Jing Wu College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen518060China Department of Materials Science and Engineering and Shenzhen Key Laboratory for Additive Manufacturing of High-Performance Materials Southern University of Science and TechnologyShenzhen518055China Aerospace Hiwing(Harbin)Titanium Industrial Co. Ltd.Harbin150028China Cryo-EM Center Southern University of Science and TechnologyShenzhen518055China

An α/β two-phase Ti-6Al-4V alloy was fabricated by electron beam melting to obtain a basketweave *** orientation dependence of the mechanical properties of Ti-6Al-4 V alloy was studied by micro-pillar compression and post-mortem transmission electron microscopy *** results indicate that different grains have different mechanical responses,and the possible attributions were *** the orientation effect,due to the limited volumes of micropillars,the size of the a phases,dispersion of the β phases,and the presence of the free dislocation path also affect the mechanical properties of the micropillars to a large *** no direct link was discovered between the mechanical properties and the parent β orientations,this work provided a promising method to further study the anisotropic mechanical behavior in Ti-6Al-4V alloy.

关键词： Electron beam melting(EBM) Ti-6Al-4V Micro-pillar compression Orientation dependence Mechanical properties

On the development of ice-water-structure interaction

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Journal of Hydrodynamics 2020年第4期32卷 629-652页

作者： Bao-yu Ni Duan-feng Han Shao-cheng Di yan-zhuo Xue College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China

Ice-water-structure interaction (IWSI) is a novel extension of the fluid-structure interaction (FSI), which is significant fordesign and operating of polar ship and offshore structures. It involves multi-media and multi-interfaces and thus is quite complicated tosolve, no matter from mathematical or mechanical perspectives. Although IWSI is complex and still very new, researchers try todevelop various methods to deal with it and relevant literature starts to bloom. This paper aims to provide concise descriptions oftypical analytical numerical and experimental methods to solve IWSI, together with a review of their major applications to date. Lastly,we succinctly highlight some development tendencies and some pieces of work to be investigated for each method.

关键词： Ice-water-structure interaction(IWSI) ice polar ships ocean engineering fluid-structure interaction(FSI)

Toeplitz operators related to strongly singular Calderón-Zygmund operators

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Science China Mathematics 2006年第8期49卷 1048-1064页

作者： LIN yan lu Shanzhen School of Mathematical Sciences Beijing Normal University Beijing 100875 China School of Mathematical Sciences Beijing Normal University Beijing 100875 China

In this paper, the boundedness of Toeplitz operator Tb(f) related to strongly singular Calderon-Zygmund operators and Lipschitz function b∈Λβ0(Rn) is discussed from Lp(Rn) to Lq(Rn), 1/q=1/p-β0/n, and from Lp(Rn) to Triebel-Lizorkin space Fβ0,∞p. We also obtain the boundedness of generalized Toeplitz operatorθbα0 from LP(Rn) to Lq(Rn), 1/q =1/p-α0+β0/n. All the above results include the corresponding boundedness of commutators. Moreover, the boundedness of Toeplitz operator Tb(f) related to strongly singular Calderon-Zygmund operators and BMO function b is discussed on LP(Rn), 1 < p <∞.

关键词： Toeplitz operator strongly singular Calderon-Zygmund operator Lipschitz space Triebel-Lizorkin space BMO.

A high propylene productivity over B2O3/SiO2@honeycomb cordierite catalyst for oxidative dehydrogenation of propane

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Chinese Journal of Chemical Engineering 2020年第11期28卷 2778-2784页

作者： Yuxi Zhou yangWang Wenduo lu Bing yan Anhui lu State Key Laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

Boron-based metal-free catalysts for oxidative dehydrogenation of propane(ODHP)have drawn great attention in both academia and industry due to their impressive activity and olefin ***,the SiO2 and B2O3 sequentially coated honeycomb cordierite catalyst is designed by a two-step wash-coat method with different B2O3 loadings(0.1%–10%)and calcination temperatures(600,700,800℃).SiO2 obtained by TEOS hydrolysis acts as a media layer to bridge the cordierite substrate and boron oxide via abundant Si\\OH *** welldeveloped straight channels of honeycomb cordierite make it possible to carry out the reactor under high gas hourly space velocity(GHSV)and the thin wash-coated B2O3 layer can effectively facilitate the pore diffusion on the *** prepared B2O3/SiO2@HC monolithic catalyst exhibits good catalytic performance at low boron oxide loading and achieves excellent propylene selectivity(86.0%),olefin selectivity(97.6%,propylene and ethylene)and negligible CO2(0.1%)at 16.9%propane conversion under high GHSV of 345,600 ml·(g B2O3)^-1·h^-1,leading to a high propylene space time yield of 15.7 g C3H6·(g B2O3)^-1·h^-1 by suppressing the *** obtained results strongly indicate that the boron-based monolithic catalyst can be properly fabricated to warrant the high activity and high throughput with its high gas/surface ratio and straight channels.

关键词： Oxidative dehydrogenation Boron-based catalyst Alkane Propylene Monolith High GHSV

Synthesis of Dispirocyclopentyl-3,3＇-bisoxindoles via Domino Cycloaddition Reactions of 4-Dimethylaminopyridinium Bromides with 3-Phenacylideneoxindoles

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Chinese Journal of Chemistry 2015年第10期33卷 1178-1188页

作者： Lijuan lu Chaoguo yan College of Chemistry & Chemical Engineering Yangzhou University Yangzhou Jiangsu 225002 China

The base mediated cycloaddition reactions of 4-dimethylamino-l-phenacylpyridinium bromides with two mo- lecular 3-phenaeylideneoxindoles in methylene dichloride afforded functionalized dispirocyclopentyl-3,3＇-bisoxin- doles in good yields and with high diastereoselectivity. The similar cycloaddition reactions of 1-（N,N-dialkylcarba- moylmethyl） and 1-cyanomethyl 4-dimethylamino-pyridinium bromide in refluxing ethanol in the presence of triethylamine a/so resulted in dispirocyclopentyl-3,3＇-bisoxindoles with high diastereoselectivity. The stereochemis- try of dispirocyclopentyl-3,3＇-bisoxindoles was elucidated on the basis of ^1H NMR data and single crystal struc- tures.

关键词： domino reaction cycloaddition reaction pyridinium N-ylide spirooxindole diastereoselectivity

Osmopriming-Regulated Changes of Plasma Membrane Composition and Function were Inhibited by Phenylarsine Oxide in Soybean Seeds

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Journal of Integrative Plant Biology 2009年第9期51卷 858-867页

作者： Jiajin zhuo Weixiang Wang Yun lu Wu Sen Xiaofeng Wang Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants Ministry of Education Beijing Forestry University Beijing 100083 China School of Bioengineering Xihua University Chengdu 610039 China

The aim of the present work was to investigate the effects of osmoconditioning on chilling injury in chilling-sensitive soybean （Glycine max （L.） Merr. Zhonghuang No. 22） seeds during imbibition. Low temperatures reduced the germination rate and no seed germinated at 1 ℃. Osmoconditioning of seeds at 20℃ with a polyethylene glycol-8000 （PEG8000） solution at 1.5 MPa for 72 h followed by drying back to their initial moisture content （MC） reduced their chilling sensitivity. The phenylarsine oxide （PAO）, an inhibitor of protein tyrosinephosphatases, was used to investigate the possible involvement of phosphorylation-dephosphorylation of Tyr residues in the plasma membrane composition and function when seeds were osmoconditioned. The results showed the germination of osmoconditioned seeds decreased significantly when PAO was added in PEG solution after chilling treatment. PAO inhibited changes in composition of plasma membrane phospholipids and fatty acid induced by osmocondition, indicated that tyrosine protein phosphorylation is involved in the regulatory mechanisms of osmocondition-responsive chilling in soybean seeds. Western blot result further indicated that osmocondition treatment improved the activity of plasma membrane H^＋-ATPase after chilling treatment, but this effect was abolished by PAO. The possible regulation mechanism by Tyr protein phosphorylation is discussed.

关键词： fatty acid membrane lipid osmoconditioning phenylarsine oxide protein-tyr phosphatases soybean seeds.

Ecotoxicological effect of zinc oxide nanoparticles on soil microorganisms

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 912-918页

作者： Zhaoyi SHEN zhuo CHEN Zhen HOU Tingting LI Xiaoxia lu Laboratory for Earth Surface Processes (Ministry of Education) College of Urban and Environmental Sciences Peking University Beijing 100871 China

The widespread production and use of zinc oxide nanoparticles （ZnO-NPs） in recent years have posed potential threat to the ecosystem. This study aimed to investigate the ecotoxicological effect of ZnO-NPs on soil microorganisms using laboratory microcosm test. Respira- tion, ammonification, dehydrogenase （DH） activity, and fluorescent diacetate hydrolase （FDAH） activity were used as ecotoxicological parameters. The results showed that in the neutral soil treated with 1 mg ZnO-NPs per g soil （fresh, neutral）, ammonification was significantly inhibited during the study period of three months, but the inhibition rate decreased over increasing time. Inhibition in respira- tion was observed in the first month of the test. In various ZnO-NPs treatments （1 rag, 5 rag, and 10 mg ZnO-NPs per g soil）, DH activity and FDAH activity were inhibited during the study period of one month. For both enzyme activities, there were positive dose-response relationships between the concentration of ZnO-NPs and the inhibition rates, but the curves changed over time due to changes of ZnO-NPs toxicity. Soil type affected the toxicity of ZnO- NPs in soil. The toxicity was highest in the acid soil, followed by the neutral soil. The toxicity was relatively low in the alkaline soil. The toxicity was not accounted for by the Zn2＋ released from the ZnO-NPs. Direct interaction of ZnO-NPs with biologic targets might be one of the reasons. The adverse effect of ZnO-NPs on soil micro- organisms in neutral and acid soils is worthy of attention.

关键词： zinc oxide nanoparticles (ZnO-NPs) soilmicroorganisms respiration ammonification dehydrogen-ase (DH) activity fluorescent diacetate hydrolase (FDAH)activity