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Effects of long-term grazing exclusion on vegetation structure,soil water holding capacity,carbon and nitrogen sequestration capacity in an alpine meadow on the Tibetan Plateau

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Journal of Mountain Science 2023年第3期20卷 779-791页

作者： YANG Yong-sheng zhang fa-wei XIE xian-rong WANG Jun-bang LI Ying-nian HUANG Xiao-tao LI Hui-ting ZHOU Hua-kun Key Laboratory of Adaptation and Evolution of Plateau Biota and Key Laboratory of Restoration Ecology in Cold Region of Qinghai Province Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Qinghai Haibei National Field Research Station of Alpine Grassland Ecosystem Xining 810008China Xi Ning Municipal Beishan Forestry farm Xining 810003China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan ***,to date,the effects of long-term grazing exclusion measures on the process of restoring degraded alpine meadows have not been *** this study,moderately degraded plots,in which the vegetation coverage was approximately 65%and the dominant plant species was Potentilla anserina L,with grazing exclusion for 2 to 23 years,were selected in alpine meadows of Haibei in Qinghai-Tibet *** coverage,plant height,biomass,soil bulk density,saturated water content,soil organic carbon(SOC)and total nitrogen(TN)were *** results were as follows:(1)With aboveground biomass and total saturated water content at 0-40 cm depth,the average SOC and TN contents in moderately degraded alpine meadows increased as a power function,and the plant height increased as a log function.(2)The average soil bulk density at 0-40 cm depth first decreased and then increased with increasing grazing exclusion duration,and the minimum value of 0.90 g·cm^(-3) was reached at 15.23 *** plant coverage,total belowground biomass at 0-40 cm depth,total aboveground and belowground biomass first increased and then decreased,their maximum values(80.49%,2452.92g·m^(-2),2891.06 g·m^(-2))were reached at 9.41,9.46 and 10.25 years,***-term grazing exclusion is apparently harmful for the sustainable restoration of degraded alpine *** optimal duration of grazing exclusion for the restoration of moderately degraded alpine meadows was 10 *** research suggests that moderate disturbance should be allowed in moderately degraded alpine meadows after 10years of grazing exclusion.

关键词： Long-term grazing exclusion Soil water holdingcapacity Soilcarbonand nitrogen sequestration Biomass Alpine meadow

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Recent advances in the research for the homolog of breast cancer associated gene AtROW1 in higher plants

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Science China(Life Sciences) 2016年第8期59卷 825-831页

作者： Yue Jiao Yuzhou zhang Yu-xian Zhu State Key Laboratory of Protein and Plant Gene Research College of Life Sciences Peking University Center for Science and Technology Development Ministry of Agriculture

BARD1(BRCA1 associated RING domain protein 1), as an important animal tumor suppressor gene associated with many kinds of cancers, has been intensively studied for decades. Surprisingly, homolog of BARD1 was found in plants and it was renamed At ROW1(repressor of Wuschel-1) according to its extremely important function with regard to plant stem cell homeostasis. Although great advances have been made in human BARD1, the function of this animal tumor-suppressor like gene in plant is not well studied and need to be further elucidated. Here, we review and summarize past and present work regarding this protein. Apart from its previously proposed role in DNA repair, recently it is found essential for shoot and root stem cell development and differentiation in plants. The study of At ROW1 in plant may provide an ideal model for further elucidating the functional mechanism of BARD1 in mammals.

关键词： repressor of Wuschel-1 DNA repair stem cell niche

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Predicting Chaotic Time Series Using Recurrent Neural Network

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Chinese Physics Letters 2000年第2期17卷 88-90页

作者： zhang Jia-Shu XIAO xian-Ci Department of Electronic Engineering University of Electronic Science and Technology of ChinaChengdu610054

A new proposed method, i.e. the recurrent neural network (RNN), is introduced to predict chaotic time series. The effectiveness of using RNN for making one-step and multi-step predictions is tested based on remarkable few datum points by computer-generated chaotic time series. Numerical results show that the RNN proposed here is a very powerful tool for making prediction of chaotic time series.

关键词： series computer neural

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A network pharmacological study on the potential mechanism of Yinchenhao Decoction in treatment of chronic hepatitis B

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Drug Combination Therapy 2019年第3期1卷 134-152页

作者： Jin-Yu zhang xian-fa Cai School of Public Health Guangdong Pharmaceutical UniversityGuangzhou510310China School of Medical Information Engineering Guangdong Pharmaceutical UniversityGuangzhou510006China

Background: Yinchenhao Decoction (YCHD), an ancient Chinese herbal medicinal compound prescribe for the treatment of jaundice, which long-term clinical experience and randomized trials have shown is effective against chronic hepatitis B (CHB). However, its mechanism remains unknown. With the gradual separation of pharmacodynamic components in YCHD and the development of computer virtual technology, network pharmacology provides an opportunity. Our study is to explore the underlying mechanism of YCHD for the treatment of CHB. Methods: The active compounds of YCHD were screened from TCMSP database, whose targets were predicted based on the ligands structures and the targets of CHB was selected from the TTD, DisGeNET, and Drugbank databases to obtain the potential targets of YCHD for CHB treating. Cytoscape 3.6.1 was applied for network analysis to identify key targets, and gene enrichment of the targets shared by both YCHD and CHB was performed by DAVID database. The virtual verification of binding abilities between the target protein and the small molecule was finally performed by the Sytems Dock platform. Results: The potentially important targets associated with CHB corresponding to 33 compound components from YCHD included ESR1, CYP1A2, PTGS2, CYP1A1, ABCG2, MMP9. Besides, enriched were the related 8 KEGG pathways (P<0.05) such as ABC transporters, Bile secretion, TNF signaling pathway. Conclusions: This study used network pharmacology method to reveal the characteristics,“multi-component and multi-target and multi-pathway”, of YCHD on CHB treatment, providing thoughts for further research.

关键词： Network pharmacology Yinchenhao Decoction Chronic hepatitis B

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Predicting Hyper-Chaotic Time Series Using Adaptive Higher-Order Nonlinear Filter

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Chinese Physics Letters 2001年第3期18卷 337-340页

作者： zhang Jia-Shu XIAO xian-Ci Department of Electronic Engineering University of Electronic Science and Technology of ChinaChengdu 610054

A newly proposed method,*** adaptive higher-order nonlinear finite impulse response(HONFIR)filter based on higher-order sparse Volterra series expansions,is introduced to predict hyper-chaotic time *** effectiveness of using adaptive HONFIR filter for making one-step and multi-step predictions is tested based on very few data points by computer-generated hyper-chaotic time series including Mackey-Glass equation and 4-dimensional nonlinear dynamical system.A comparison is made with some neural networks for predicting the Mackey-Glass hyper-chaotic time *** simulation results show that the adaptive HONFIR filter proposed here is a very powerful tool for making prediction of hyper-chaotic time series.

关键词： chaotic nonlinear Nonlinear

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Preparation and Optical Properties of Nanocrystalline Ga0.62In0.38Sb Embedded in SiO2 Composite Films

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Chinese Physics Letters 2000年第2期17卷 142-144页

作者： LIU fa-Min zhang Li-De Institute of Solid State Physics Chinese Academy of SciencesHefei 230031

Nanocrystalline Ga0.62In0.38Sb embedded in SiO2 matrix has been fabricated by radio frequency magnetron cosputtering. X-ray photoelectron spectroscopy strongly supports the existence of nanocrystalline Ga0.62In0.38Sb embedded in SiO2 matrix. The room-temperature Raman spectrum shows that the Raman peaks of the Ga0.62In0.38SbSiO2 composite film have a larger red shift of about 95.3 cm-1 (longitudinal-optic) and 120.1 cm-1 (transverseoptic) than those of the bulk GaSb. This can be explained by the phonon confinement and tensile stress effects. The room-temperature optical transmission spectra show that the absorption edge exhibits a large blue shift of about 2.43 eV compared with that of the bulk semiconductor, suggesting the existence of quantum size effects.

关键词： composite transverse Preparation

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Preparation, characterization, and adsorption-photocatalytic activity of nano TiO_2 embedded in diatomite synthesis materials

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Rare Metals 2017年第12期36卷 987-991页

作者： Ya-Li zhang Jing Yang xian-Jin Yu School of Chemical-Engineering Shandong University of Technology Zibo 255049 China

Nano TiOembedded in diatomite(NTED)synthesis materials were prepared by a sol-gel method in absolute ethyl alcohol suspension. NTED synthesis materials have a higher specific surface area and larger pore volume using micromeritics ASAP 2020. The result of characterization was measured by X-ray diffraction(XRD),Fourier transform infrared(FT-IR) spectroscopy, scanning electron microscope(SEM), and energy dispersive spectroscopy(EDS). The cyanide wastewater was employed to evaluate the adsorption capacity and photocatalytic activity of prepared NTED synthesis materials. The better photocatalytic activity and adsorption capacity of NTED synthesis materials are attributed to their high surface area and higher UV absorption intensity for the cyanide wastewater.

关键词： Nano TiO_2 Diatomite(NTED) Embedded Adsorption Photocatalysis

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On a Damped Vibration Problem Involving p-Laplacian Operator:fast Homoclinic Orbits

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 368-387页

作者： Peng CHEN xian-hua TANG Yuan-yuan zhang Three Gorges Mathematical Research Center China Three Gorges UniversityYichang 443002China College of Science China Three Gorges UniversityYichang 443002China School of Mathematics and Statistics Central South UniversityChangsha 410083China

In this paper,we deal with the nonlinear second-order differential equation with damped vibration term involving p-Laplacian *** particular interest is the resolution of an open *** interesting outcome from our result is that we can obtain the fast homoclinic solution with general superlinear growth assumption in suitable Sobolev *** our knowledge,our theorems appear to be the first such result about damped vibration problem with p-Laplacian operator.

关键词： fast homoclinic solutions damped vibration problem variational method

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Forming the transverse inner rib of a curved generatrix part through power spinning

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Advances in Manufacturing 2019年第1期7卷 105-115页

作者： Hong-Rui zhang Mei Zhan Jing Guo xian-xian Wang Peng-Fei Gao Fei Ma State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 People's Republic of China Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 People's Republic of China Long March Machinery factory China Aerospace Science and Technology Corporation Chengdu 610100 People's Republic of China

How to form high-quality transverse inner ribs through power spinning is a key issue for complicated integrated curved generatrix parts with transverse inner ribs. In this study, the forming characteristics and laws during the power spinning process were investigated using a finite element simulation based on the orthogonal design method. The results show that the transverse inner rib distributes homogeneously along the circumferential direction but inhomogeneously along the generatrix direction. Depressions occur easily in the middle zone of the rib (MZR). The roller nose radius is the most significant parameter of the MZR underfill degree. A larger roller nose radius is helpful to decrease the MZR underfill degree. Furthermore, the preformed billet thickness also plays a vital role in the underfill degree of the front zone of the rib and the back zone of the rib, as well as the depression degree of the outer surface of the rib. By combining the ribfilling characteristics and laws, the optimized forming process window for obtaining high-quality inner ribs was obtained by regression analysis, thus laying a basis for improving the forming quality of curved generatrix parts with transverse inner ribs in power spinning.

关键词： Power spinning Transverse inner rib Rib filling Process optimization

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Structures of sodium vanadate solution under different conditions

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Rare Metals 2018年第1期37卷 59-65页

作者： Ya-Li zhang Li-Qun Yang xian-Jin Yu School of Chemical Engineering Shandong University of Technology

Combined with Fourier transform infrared spectroscopy（FTIR） analysis of sodium vanadate solution,the relationship between conductivity and structure was investigated by measuring the electric conductivity of the solution under different alkali concentrations and molar ratios of NaOH to V2O5. Results suggest that the polymerization vanadium acid radical ions gradually transform into monomer with the solution diluting. When the solution is diluted to a certain extent,only the vanadium acid radical ion with V-OH chemical bond exists in the solution. At NaOH concentration of below 105.21 g·L^（-1）,the vanadate anions mainly exist in the form of vanadium acid radical ion with V-OH chemical bond and the ion transference number is approximately from 0.58 to 0.82. In the medium NaOH concentration range of 105.21-117.03 g·L^（-1）, the vanadate anions mostly exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds and the ion transference number is approximately 3.29. At NaOH concentration of above 117.03 g·L^（-1）, vanadate anions exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds.

关键词： Sodium vanadate solution Electric conductivity Migration number Infrared spectroscopy

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