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Phyton-International Journal of Experimental Botany 2023年第7期92卷 1987-1999页

作者： Xu Gao Ziqi shen Jinliang Xu Min Fan Qiang Li College of Agronomy Hunan Agricultural UniversityChangsha410128China

Phytophthora nicotianae causes substantial economic losses in most countries where tobacco is *** present,the control of *** mainly depends on chemical methods,with considerable environmental and health *** investigated the effects of ethanol extracts from Scutellaria baicalensis Georgi(SBG)and Magnolia officinalis(MO).On mycelial growth,sporangium formation,and zoospore release of *** extracts inhibited the growth of ***,with mycelial growth inhibition rates of 88.92%and 93.92%,respectively,at 40 mg/mL,and EC50 values of 5.39 and 5.74 mg/mL,*** underlying mechanisms were the inhibition of sporangium formation,the reduction of zoospore number,and the destruction of the mycelium *** an SBG extract concentration of 16.17 mg/mL,the inhibition rates for sporangia and zoospores were 98.66%and 99.39%,*** an MO extract concentration of 2.87 mg/mL,the production of sporangia and zoospores was completely *** hyphae treated with the two plant extracts showed different degrees of deformation and *** treated with SBG extract showed adhesion and local swelling,whereas treatment with MO extract resulted in broken *** of the extracts resulted in a good synergistic effect.

关键词： Phytophthora nicotianae bacteriostatic activity Scutellaria baicalensis Georgi Magnolia officinalis

Submergence induced changes of molecular species in membrane lipids in Arabidopsis thaliana

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Plant Diversity 2016年第3期38卷 156-162页

作者： Mulan Wang Yunmei shen Faqing Tao shengchao Yang Weiqi Li Yunnan Research Center on Good Agricultural Practice for Dominant Chinese Medicinal Materials Yunnan Agriculture University Kunming 650201 China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China Department of Biology Honghe University Mengzi 661100 China Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China

The composition of membrane lipids is sensitive to environmental *** is a type of stress often encountered by ***,how the molecular species of membrane lipids respond to submergence has not yet been *** this study,we used a lipidomic approach to profile the molecular species of membrane lipids in whole plants of Arabidopsis thaliana that were completely submerged for three *** plants survived one day of submergence,after which,we found that the total membrane lipids were only subtly decreased,showing significant decreases of monogalactosyldiacylglycerol(MGDG)and phosphatidylcholine(PC)and an increase of phosphatidic acid(PA);however,the basic lipid composition was *** contrast,three days of submergence caused plants to die,and the membranes deteriorated via the rapid loss of 96% of lipid content together with a 229% increase in *** turnover of molecular species from PG and MGDG to PA indicated that submergenceinduced lipid changes occurred through PA-mediated *** addition,molecular species of extraplastidic PG degraded sooner than plastidic ones,lyso-phospholipids exhibited various patterns of change,and the double-bond index(DBI)remained unchanged until membrane *** results revealed the unique changes of membrane lipids upon submergence and suggested that the major cause of the massive lipid degradation could be anoxia.

关键词： Submergence Anoxia stress Membrane lipids Lipidomics Arabidopsis thaliana

Modeling of Mold Filling and Solidification in Lost Foam Casting

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Journal of Materials Science & Technology 2003年第5期19卷 395-397页

作者： Fengjun LI, Houfa shen and Baicheng LIUDepartment of Mechanical Engineering, Tsinghua University, Beijing 100084, China Dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China

Based on the characteristics of the lost foam casting (LFC) and the artificial neural network technique, a mathematical model for the simulation of the melt-pattern interface movement during the mold filling of LFC has been proposed and experimentally verified. The simulation results are consistent with the experiments in both the shapes of melt front and filling sequences. According to the calculated interface locations, the fluid flow and the temperature distributions during the mold filling and solidification processes were calculated, and the shrinkage defect of a lost foam ductile iron casting was predicted by considering the mold wall movement in LFC. The simulation method was applied to optimize the casting design of lost foam ductile iron castings. It is shown that the model can be used for the defects prediction and for casting design optimization in the practical LFC production.

关键词： Lost foam casting Numerical simulation Artificial neural network

Direct Pyrolysis of Molybdophosphate-based Ionic Salt for One-step Synthesis of N,P Co-doped Carbon/Mo03-x Hybrids with Superior Lithium Storage Performance

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Chemical Research in Chinese Universities 2019年第5期35卷 842-847页

作者： ZHANG Lifeng shen Kechao JIANG Yongtao GUO Yu LIU Yi GUO Shouwu School of Materials Science and Engineering Shaanxi University of Science and TechnologyXian 710021P.R.China Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials Shaanxi University of Science and TechnologyXi'an 710021P.R.China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240P.R.China

N, P co-doped carbon/MoO3-x hybrids(NPC/MoO3-x) were synthesized via one-step pyrolysis of molybdophosphate-based ionic salt precursor. Doped carbon and oxygen vacancies(OVs) were synchronously introduced into the NPC/MoO3-x hybrids without any other redundant procedure. As anodes for lithium-ion batteries, the NPC/MoO3-x hybrids delivered a high initial Coulombic efficiency(ICE) of 81% as well as high charge capacity of 516 mA·h/g after 100 cycles at 1 A/g, indicating the excellent reversibility and rate capability. The enhanced lithium storage performance was attributed to the rational combination of surface engineering and OVs, which is beneficial to the more active sites and fast ionic/electronic transport.

关键词： Lithium ion battery Anode Molybdenum oxide Doped carbon Oxygen vacancy

Study on the Deformation Mechanism of a Soft Rock Tunnel

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Fluid Dynamics & Materials Processing 2022年第2期18卷 243-255页

作者： Jianhui Yang Kai shen Shoudong Pan Shuren Wang Zhengsheng Zou School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou310023China China Railway 16 Bureau Group Co. Ltd.Beijing100018China School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

The large deformation of soft rock tunnel is one of the key problems to be overcome in the tunnel construction *** the present study,the deformation mechanism of a representative tunnel and some related countermeasures are investigated using field tests and engineering geological *** to the scarce performances of methods based on other criteria such as small pipe spacing,anchor bolt length and steel frame spacing,a new support scheme is implemented and *** show that shear failure and bedding sliding are produced under high horizontal stress *** low strength of the surrounding rock results in the uneven convergence of both sides of the *** the aforementioned new support scheme,however,most of such problems can be mitigated leading to good stability properties and ensuing economic advantages.

关键词： Soft rock tunnel high stress deformation mechanism supporting countermeasure

Application of an amphipathic molecule at the NiO_(x)/perovskite interface for improving the efficiency and long-term stability of the inverted perovskite solar cells

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Journal of Energy Chemistry 2023年第3期78卷 454-462,I0013页

作者： Guibin shen Hongye Dong Fan Yang Xin Ren Ng Xin Li Fen Lin Cheng Mu Key Laboratory of Advanced Light Conversion Materials and Biophotonics Department of ChemistryRenmin University of ChinaBeijing 100872China Solar Energy Research Institute of Singapore(SERIS) National University of SingaporeSingapore 117574Singapore State Key Laboratory of Materials Processing and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117574Singapore

The presence of defects and detrimental reactions at NiO_(x)/perovskite interface extremely limit the efficiency performance and long-term stability of the perovskite solar cells(PSCs) based on NiO_(x).Herein,an amphipathic molecule Triton X100(Triton) is modified on the NiO_(x)*** hydrophilic chain of Triton as a Lewis base additive can coordinate with the Ni3+on the NiO_(x)surface which can passivate the interfacial defects and hinder the detrimental reactions at the NiO_(x)/perovskite ***,the hydrophobic chain of Triton protrudes from the NiO_(x)surface to prevent moisture from penetrating into the NiO_(x)/perovskite ***,the NiO_(x)/Triton-based devices(MAPbI3as absorbing layer) show superior moisture and thermal stability,retaining 88.4% and 64.3% of the initial power conversion efficiency after storage in air(40%-50% relative humidity(RH)) at 25 ℃ for 1070 h and in N2at 85℃ for 800 h,***,the efficiency increases from 17.59% to 19.89% because of the passivation defect and enhanced hole-extraction ***,the NiO_(x)/Triton-based PSCs with Cs_(0.05)(MA_(0.15)FA_(0.85))_(0.95)Pb(I_(0.85)Br_(0.15))3perovskite as the light-absorbing layer also exhibits better moisture and thermal stability compared to the control devices,indicating the viability of our *** particular note,a champion PCE of 22.35% and 20.46% was achieved for small-area(0.1 cm^(2)) and large-area(1.2 cm^(2)) NiO_(x)/Triton-based devices,respectively.

关键词： Perovskite solar cells NiO_(x) Defect passivation Long-term stability Amphipathic molecule

Multispectral point cloud superpoint segmentation

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Science China(Technological Sciences) 2024年第4期67卷 1270-1281页

作者： WANG QingWang WANG MingYe ZHANG ZiFeng SONG Jian ZENG Kai shen Tao GU YanFeng Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China Yunnan Key Laboratory of Computer Technologies Application Kunming 650500China School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

The multitude of airborne point clouds limits the point cloud processing *** are grouped based on similar points,which can effectively alleviate the demand for computing resources and improve processing ***,existing superpoint segmentation methods focus only on local geometric structures,resulting in inconsistent spectral features of points within a *** feature inconsistencies degrade the performance of subsequent ***,this study proposes a novel Superpoint Segmentation method that jointly utilizes spatial Geometric and Spectral Information for multispectral point cloud superpoint segmentation(GSI-SS).Specifically,a similarity metric that combines spatial geometry and spectral information is proposed to facilitate the consistency of geometric structures and object attributes within segmented *** the formation of the primary superpoints,an intersuperpoint pointexchange mechanism that maximizes feature consistency within the final superpoints is *** are conducted on two real multispectral point cloud datasets,and the proposed method achieved higher recall,precision,F score,and lower global consistency and feature classification *** experimental results demonstrate the superiority of the proposed GSI-SS over several state-of-the-art methods.

关键词： multispectral point cloud superpoint segmentation over-segmentation spatial-spectral joint metric

Vegetation evolution on the central Chinese Loess Plateau since late Quaternary evidenced by elemental carbon isotopic composition

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Chinese Science Bulletin 2009年第12期54卷 2082-2089页

作者： ZHOU Bin shen ChengDe ZHENG HongBo ZHAO MeiXun SUN YanMin School of Earth Science and Engineering Nanjing University Nanjing 210093 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China School of Ocean and Earth Science Tongji University Shanghai 200092 China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao 266100China

There are many controversial issues in loess studies such as natural vegetation types on the Chinese Loess Plateau during the historical periods and the spatial and temporal evolution of C3/C4 plants. Elemental carbon isotopic composition (δ13Cec) in the loess section may offer new evidence for these problems. Elemental carbon (EC) is produced by incomplete combustion of vegetation, and its carbon isotopic composition has a very small difference from that of the formal vegetation, then δ13Cec can be used as a record to recover the changes of vegetation. Elemental carbon was extracted by applying the oxidation method from the loess-paleosol sequence in the central Chinese Loess Plateau, and its carbon isotope composition was analyzed by the isotope mass spectrometer. The results showed that the vegetation in this region was a mixed type of C3 and C4 plants, dominated with C3 plants in most of the time. Since late Quaternary, C3/C4 plants may not follow a simple glacial-interglacial cycle mode on the Chinese Loess Plateau, but showing fluctuations. C3 plants increased gradually in L4 period, and more C3 plants occurred during S3 period, and C4 plants increased again during L3―L2 periods, after that, C3 plants dominated again during S1―S0 periods. During periods of paleosol development, C3 plants were abundant in S3 and S1, and there were more C4 plants in S2 and S0. During periods of loess sedimen- tation, there were more C3 plants in L4 and L1, and there were more C4 plants in L3 and L2. On the or- bital timescale, the vegetation variations revealed by δ13Cec record are consistent with the results of pollen data and also similar to the results obtained by organic carbon isotopic composition since the last glacial period.

关键词：碳同位素组成黄土高原植被演变晚第四纪元素碳 C4植物 C3植物证明

Hepatitis B virus infection and genotype in asymptomatic people from 10 ethnic groups in Yunnan, China

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World Journal of Gastroenterology 2015年第44期21卷 12586-12592页

作者： Yuan-Ying shen Wei Hou Zhan-Qiu Yang Wen Xiao Institute of Virology Medical School of Wuhan University Dali University Institute of Eastern-Himalaya Biodiversity Research Dali University

AIM: To evaluate the infection and genotype distribution of hepatitis B virus(HBV) in ethnic groups in Yunnan, ***: Two thousand five hundred and eightyfour asymptomatic local people from 10 ethnic groups were investigated in Yunnan, China. Infection and genotype distribution were evaluated by serological and genetic methods. Genotyping was verified by sequencing. Ethnic genotype distribution was compared by proportion test. RESULTS: Four types of infection model based on HBV serum markers were identified, and the average HBV infection rate was 5.7% in those asymptomatic local people. The genotype prevalence was 59.6% for B, 21.1% for C and 19.3% BC; subgenotypes Ba, Cs and Ce were identified in this study. Hepatitis B surface antigen-positive rate and the proportion of genotype B were significantly lower in ethnic groups with a northern origin compared to those with a southern origin(50% vs 73.9%, P = 0.037; 4.2% vs 10.5%, P = 0.000).CONCLUSION: Genotype B is dominant and genotype BC has high occurrence in asymptomatic local ethnic groups in Yunnan. HBV infection status and genotype distribution may associate with ethnic origin.

关键词： Hepatitis B virus Infection and genotype Ethnic di

Influence of abnormal stress under a residual bearing coal pillar on the stability of a mine entry

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International Journal of Mining Science and Technology 2017年第6期27卷 945-954页

作者： Kang Jizhong shen Wenlong Bai Jianbiao Yan Shuai Wang Xiangyu Li Wenfeng Wang Ruofan School of Mines China University of Mining & Technology School of Energy Science and Engineering Henan Polytechnic University Mewbourne School of Petroleum and Geological Engineering University of Oklahoma

Mine entries close to residual bearing coal pillars(RBCPs) will suffer large deformation that may cause rock burst. To better understand the deformation mechanism and develop safe and practical guidelines for entry design, most studies focus on the absolute size of the stress field in and around the pillar. In this paper, we present a new approach to analyze the abnormal stress field close to a RBCP that uses the stress concentration coefficient(SCC), stress gradient(SG), and coefficient of lateral pressure(CLP) to describe the stress state induced by the RBCP. Based on elastic theory and a mathematical model for the abutment stress in the RBCP, an analytical solution for the abnormal stress in the strata below the RBCP was derived and the characteristics of the abnormal stress for a case study of a coal mine in China were analyzed. The results show that the abnormal stress field around the pillar is characterized by four distinct zones: a zone of high SCC, high SG, and CLP less than 1, a zone of high SCC, low SG, and CLP less than 1, a zone of low SCC, SG close to 0, and CLP greater than 1, and a zone of SCC close to 1, SC close to 0, and CLP close to 1. Based on this zoning pattern, a numerical model was established to study the combined effects of the abnormal stress on the stability of the entry. The most stable zone was determined based on a model of the Xinrui coal mine and verified by field measurements at the mine. Our conclusions can be used as guidelines for designing safe entry layouts in similar geological and mining settings.

关键词： Residual bearing coal pillar Abnormal stress Entry layout Mechanical analysis Numerical computation