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Journal of Forestry Research 2021年第2期32卷 741-753页

作者： wei tang Anna Y.tang College of Arts and Science East Carolina UniversityGreenvilleNC 27858USA 101 Stadium Drive University of North Carolina at Chapel HillChapel HillNC 27514USA

Malonyl-CoA synthetases may modulate cell responses to abiotic stress by regulating stress-related signaling transduction pathways or activating expression of transcription ***,the molecular mechanism of cold stress tolerance enhanced by malonyl-CoA synthetase is not fully ***,we report that overexpression of the Arabidopsis thaliana malonyl-CoA synthetase gene AAE13.1 resulted in increased cell viability and growth rate and decreased thiobarbituric acid reactive substances under cold stress in rice(Oryza sativa L.),tobacco(Nicotiana tabacum),and slash pine(Pinus elliottii Engelm.).AAE13.1 was associated with cold stress tolerance by increasing the activity of ascorbate peroxidase,catalase,polyphenol oxidase,and peroxidase and the accumulation of acid phosphatase and alkaline *** six rice mitogenactivated protein kinase(MAPK)genes examined,AAE13.1 overexpression increased the expression of OsMAPK genes during cold ***13.1 activated expression of stressresponse genes OsMAPK1,OsMAPK2,and OsMAPK3,indicating that AAE13.1 enhances cold stress tolerance by regulating expression of MAPK genes in plant *** results increase our understanding of cold stress tolerance in species of monocotyledons,dicotyledons,and gymnosperms.

关键词： Cold stress Malonyl-CoA synthetase gene MAPK transcription factor Phosphatase Pinus

Flexible perovskite solar cells based on green,continuous roll-to-roll printing technology

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Journal of Energy Chemistry 2018年第4期27卷 971-989页

作者： wei zi Zhiwen Jin Shengzhong Liu Baomin Xu Energy-saving Building Materials Innovative Collaboration Center of Henan Province.Xinyang Normal University Xinyang 464000HenanChina Department of Materials Science and Engineering.Southern University of Science and Technology Shenzhen 518055GuangdongChina Dalian Institute of Chemical Physics.Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023.LiaoningChina Key Laboratory of Applied Surface and Colloid Chemistry National Ministry of EducationShaanxi Engineering Lab for Advanced Energy TednologySchool of Materials Science and EngineeringShaanxi Normal University.Xi'an 710119ShaanxiChina

By designing and fabricating thin film electronic devices on a flexible substrate instead of more commonly used rigid substrate, flexible electronics produced has opened a field of special applications. In this article, we first reviewed available products that may be used as flexible substrates, their characteristics and unique advantages as supporting material for flexible electronic devices. Secondly, flexible perovskite solar cell is examined in detail, with special focus on its potential large-scale fabrication processes. In particular, a comprehensive review is provided on low cost solution printing techniques that is viewed highly as a viable tool for potential commercialization of the perovskite solar cells. Furthermore, a summary is given on green processing for the solution printing production of flexible perovskite devices.

关键词： Flexible substrate Perovskite solar cell Doctor blading Slot-die coating Inkier printing

Overexpression of Arabidopsis thaliana cysteine2/histidine2-type transcription factor 6 gene enhances plant resistance to a bacterial pathogen

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Journal of Forestry Research 2021年第1期32卷 249-262页

作者： wei tang Anna Y.tang College of Arts and Science East Carolina UniversityGreenvilleNC 27858USA 2 Stadium Drive University of North Carolina at Chapel HillChapel HillNC 27514USA

Transcription factors can be used to engineer plants for enhanced ***,the mechanism(s)by which the C2H2-type zinc fi nger transcription factor enhances pathogen resistance in cells is not fully ***,Agrobacterium tumefaciens carrying the gene for Arabidopsis thaliana cysteine2/histidine2-type transcription factor 6(ZAT6)was used to engineer rice(Oryza sativa L.),cotton(Gossypium hirsutum L.),and slash pine(Pinus elliottii Engelm.)to generate transgenic cell *** cells were then inoculated with the pathogenic bacterium Pseudomonas *** to the control,cell viability of transgenic cells increased 39–47%and growth rate increased 9–15%by 7 days after inoculation in rice,cotton and slash *** phosphatase activity and alkaline phosphatase activity and transcript levels of Ca 2+-dependent protein kinase genes OsCPK1,OsCPK2,OsCPK6,and OsCPK8 and mitogen-activated protein kinase genes OsMAPK1,OsMAPK2,OsMAPK3,and OsMAPK8 increased signifi cantly in transgenic rice cells by 3 day after inoculation,and extracellular pH had decreased by 10–14%by 96 min after inoculation in transgenic rice,cotton and slash pine *** results suggest that ZAT6 enhances *** resistance in plant cells by modulating transcription of CPK and MAPK and oxidase activity.

关键词： Ca^2+-dependent protein kinase Mitogenactivated protein kinase Oxidase Pathogen Pinus

Material analysis of the fatigue mechanism of rollers in tapered roller bearings

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Science China(Technological Sciences) 2018年第7期61卷 1003-1011页

作者： GUO wei CAO HongRui zi YanYang HE ZhengJia State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University

Rolling contact fatigue is the main failure mechanism of tapered roller bearings. This study investigated the fatigue mechanism of rollers in a tapered roller bearing that failed in a run-to-failure test. Roller microstructure and crack morphology were investigated through scanning electron microscopy. A microhardness test was performed to investigate the strain hardening of the roller material induced by rolling contact fatigue. Results showed that microcavities and holes are important influential factors of crack initiation and propagation. Crack propagation angle affects crack morphology and propagation mode. Material strain hardening accelerates crack growth. Furthermore, roller misalignment causes uneven hardenability and severe damage to roller ends.

关键词： rolling contact fatigue mechanism crack propagation material microstructure roller misalignment

A novel cascaded H-bridge photovoltaic inverter with flexible arc suppression function

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Global Energy Interconnection 2024年第4期7卷 513-527页

作者： Junyi tang wei Gao College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108P.R.China

This paper presents a novel approach that simultaneously enables photovoltaic(PV)inversion and flexible arc suppression during single-phase grounding *** compensate for ground currents through an arc-elimination function,while outputting a PV direct current(DC)power *** method effectively reduces the residual grounding *** reduce the dependence of the arc-suppression performance on accurate compensation current-injection models,an adaptive fuzzy neural network imitating a sliding mode controller was *** online adaptive adjustment law for network parameters was developed,based on the Lyapunov stability theorem,to improve the robustness of the inverter to fault and connection ***,a new arc-suppression control exit strategy is proposed to allow a zerosequence voltage amplitude to quickly and smoothly track a target value by controlling the nonlinear decrease in current and reducing the regulation *** results showed that the proposed method can effectively achieve fast arc suppression and reduce the fault impact current in single-phase grounding *** to other methods,the proposed method can generate a lower residual grounding current and maintain good arc-suppression performance under different transition resistances and fault locations.

关键词： Photovoltaic inverter Flexible arc suppression Adaptive control Fuzzy neural network Sliding mode control Exit strategy

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疏花蔷薇果总多酚抗氧化活性

安徽农业科学 2016年第1期44卷 162-164页

作者：王东东汤紫薇党稳梅郭萍萍王慧杰田莉新疆医科大学中医学院新疆乌鲁木齐830011

[目的]研究疏花蔷薇果中总多酚的抗氧化能力,为进一步开发疏花蔷薇果提供试验数据。[方法]利用已优化的响应曲面法提取疏花蔷薇果中的总多酚,并测定其含量;应用3种抗氧化模型(清除DPPH自由基、清除羟基自由基、清除超氧阴离子自由基),... 详细信息

[目的]研究疏花蔷薇果中总多酚的抗氧化能力,为进一步开发疏花蔷薇果提供试验数据。[方法]利用已优化的响应曲面法提取疏花蔷薇果中的总多酚,并测定其含量;应用3种抗氧化模型(清除DPPH自由基、清除羟基自由基、清除超氧阴离子自由基),建立疏花蔷薇果中的多酚类成分抗氧化能力模型,以抗坏血酸为阳性对照,评价疏花蔷薇果中总多酚的体外抗氧化能力。[结果]在试验浓度范围内,疏花蔷薇果总多酚对羟基自由基、超氧阴离子自由基、DPPH自由基均有较强的清除能力,其清除率与总多酚浓度有一定的量效关系。[结论]疏花蔷薇果总多酚有明显的清除自由基能力,可以作为一种有效的天然抗氧化剂来开发利用。

关键词：疏花蔷薇果总多酚抗氧化活性

Bayesian inference of the crust–core transition density via the neutron-star radius and neutron-skin thickness data

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Nuclear Science and Techniques 2023年第6期34卷 125-133页

作者： Wen-Jie Xie zi-wei Ma Jun-Hua Guo Department of Physics Yuncheng UniversityYuncheng044000China

In this work,we perform a Bayesian inference of the crust-core transition density ρ_(t) of neutron stars based on the neutron-star radius and neutron-skin thickness data using a thermodynamical *** and Gaussian distributions for the ρ_(t) prior were adopted in the Bayesian *** has a larger probability of having values higher than 0.1 fm^(−3) for ρ_(t) as the uniform prior and neutron-star radius data were *** was found to be controlled by the curvature K_(sym) of the nuclear symmetry *** phenomenon did not occur if K_(sym) was not extremely negative,namely,K_(sym)>−200 *** value ofρ_(t) obtained was 0.075_(−0.01)^(+0.005) fm^(−3) at a confidence level of 68%when both the neutron-star radius and neutron-skin thickness data were *** anti-correlations were observed between ρ_(t),slope L,and curvature of the nuclear symmetry *** dependence of the three L-K_(sym) correlations predicted in the literature on crust-core density and pressure was quantitatively *** most probable value of 0.08 fm^(−3) for ρ_(t) was obtained from the L-K_(sym) relationship proposed by Holt et *** larger values were preferred for the other two relationships.

关键词： Crust–core transition density of neutron stars Neutron-star radius Neutron-skin thickness Bayesian inference approach L–K_(sym)

MicroRNAs associated with molecular mechanisms for plant root formation and growth

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Journal of Forestry Research 2016年第1期27卷 1-12页

作者： wei tang Anna Y.tang Department of Biology East Carolina University 101 Stadium Drive University of North Carolina at Chapel Hill

Although roots are so important for plant growth and crop productivity, the molecular mecha- nism（s） of root formation and growth is not fully under- stood. To increase our understanding of the underlying molecular mechanisms, here we review microRNA regu- lation of processes related to root formation： the regulation of transcription factors, nutrient uptake, stress signaling, and growth signaling. We have summarized the interaction, expression, transport, and signaling events that involve microRNAs in ideal and stressed conditions in a number of model plants, highlighting the involvement of microRNAs in root formation. MicroRNAs are now known to be important players in root initiation, development, and growth; understanding the precise mechanisms involved will be valuable for plant molecular breeding to develop high-yielding crops with high stress resistance and low nutrient requirements.

关键词： MicroRNAs, Nutrient. Root formationStress response Transcription factor

Genome engineering technologies for targeted genetic modification in plants

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Journal of Forestry Research 2018年第4期29卷 875-887页

作者： wei tang Anna Y. tang College of Arts and Science East Carolina University Greenville NC 27858 USA University of North Carolina at Chapel Hill 101 Stadium Drive Chapel Hill NC 27514 USA

Well-established targeted technologies to engi- neer genomes such as zinc-finger nuclease-based editing （ZFN）, transcription activator-like effector nuclease-based editing （TALEN）, and clustered regularly interspaced short palindromic repeats and associated protein system-based editing （CRISPR/Cas） are proving to advance basic and applied research in numerous plant species. Compared with systems using ZFNs and TALENs, the most recently developed CRISPR/Cas system is more efficient due to its use of an RNA-guided nuclease to generate double-strand DNA breaks. To accelerate the applications of these technologies, we provide here a detailed overview of these systems, highlight the strengths and weaknesses of each, summarize research advances made with these technologies in model and crop plants, and discuss their applications in plant functional genomics. Such targeted approaches for genetically modifying plants will benefit agricultural production in the future.

关键词： Double-stranded DNA break Genomeediting CRISPR system Transcription activator-likeeffector nucleases zinc-finger nucleases

Numerical investigation on the effect of depletion-induced stress reorientation on infill well hydraulic fracture propagation

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Petroleum Science 2022年第1期19卷 296-308页

作者： Feng-Shou Zhang Liu-Ke Huang Lin Yang Egor Dontsov Ding-wei Weng Hong-Bo Liang zi-Rui Yin Ji-Zhou tang Key Laboratory of Geotechnical&Underground Engineering of Ministry of Education Tongji UniversityShanghai200092China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China ResFrac Corporation Palo AltoCA94301USA PetroChina Research Institute of Petroleum Exploration and Development Langfang065007China State Key Laboratory of Marine Geology Tongji UniversityShanghai200092China School of Ocean and Earth Science Tongji UniversityShanghai200092China

Depletion-induced stress change causes the redistribution of stress field in reservoirs,which can lead to the reorientation of principal *** reorientation has a direct impact on fracture propagation of infill *** understand the effect of stress reorientation on the propagation of infill well’s fractures,an integrated simulation workflow that combines the reservoir flow calculation and the infill well hydraulic fracturing modeling is *** reservoir simulation is computed to examine the relationship between the extent of stress reversal region and reservoir ***,the hydraulic fracturing model considering the altered stress field for production is built to characterize the stress evolution of secondary *** simulations show that stress reorientation may occur due to the decreasing of the horizontal stresses in an elliptical region around the parent ***,the initial stress difference is the driving factor for stress ***,the bottom hole pressure,permeability and other properties connected with fluid flow control timing of the stress *** decrease of the horizontal stresses around the parent well lead to asymmetrical propagation of a hydraulic fracture of the infill *** study provides insights on understanding the influence of stress reorientation to the infill well fracturing treatment and interference between parent and infill wells.

关键词： Infill well Depletion Hydraulic fracture Stress reorientation Asymmetry fracture