检索结果-南通市图书馆

维普期刊数据库博看期刊

玉米新害虫一点缀螟肠道细菌组成结构与多样性及功能预测

在线全文

学校读者我要写书评

暂无评论

南方农业学报 2024年第2期55卷 355-365页

作者：姚云昊王文倩杜广祖沈云峰孟继枝肖文祥陈斌云南农业大学植物保护学院/云南生物资源保护与利用国家重点实验室云南昆明650201 云南省保山市植保植检站云南保山678000

【目的】明确一点缀螟[Paralipsa gularis(Zeller)]幼虫肠道细菌组成结构与多样性并预测其功能,为后续挖掘该害虫肠道的功能菌及制定其综合防治策略提供理论依据。【方法】以云南省保山和芒市一点缀螟种群为研究对象,利用传统分离培养... 详细信息

【目的】明确一点缀螟[Paralipsa gularis(Zeller)]幼虫肠道细菌组成结构与多样性并预测其功能,为后续挖掘该害虫肠道的功能菌及制定其综合防治策略提供理论依据。【方法】以云南省保山和芒市一点缀螟种群为研究对象,利用传统分离培养法并结合高通量测序技术,对2个地理种群一点缀螟3龄幼虫肠道细菌进行分离鉴定和测序,分析其组成结构与多样性,并通过KEGG代谢通路分析不同地理种群一点缀螟幼虫肠道细菌功能基因的表达情况。【结果】保山一点缀螟种群3龄幼虫肠道细菌有23门48纲120目211科375属,优势属是肠球菌属(Enterococcus,38.02%)和肠杆菌属(Enterobacter,17.24%);共分离到可培养细菌2门4科5属10种,优势门、科、属、种分别是厚壁菌门(72.73%)、芽孢杆菌科(36.36%)、芽孢杆菌属(36.36%)和鹑鸡肠球菌(45.34%)。芒市一点缀螟幼虫肠道细菌有6门9纲22目46科69属,优势属是肠球菌属(56.13%)和肠杆菌科未知属(15.02%);共分离到可培养细菌2门4科4属8种,优势门、科、属、种分别是厚壁菌门(62.50%)、芽孢杆菌科(62.50%)、芽孢杆菌属(62.50%)和高地芽孢杆菌(33.85%)。保山一点缀螟种群3龄幼虫肠道细菌群落ACE指数、Chao1指数、Simpson指数和Shannon指数分别为852.00、852.00、0.93和6.03,均高于芒市种群的对应指数(196.18、196.00、0.91和4.73)。KEGG代谢途径差异分析结果显示,一点缀螟幼虫肠道细菌主要参与膜运输、氨基酸和碳水化合物等代谢过程。【结论】一点缀螟幼虫肠道细菌种类丰富,有23门48纲121目225科408属,其肠道细菌群落多样性随着地理环境条件的改变而存在差异,其中保山种群肠道细菌群落组成及多样性高于芒市种群。一点缀螟幼虫肠道细菌可能参与膜运输、氨基酸和碳水化合物等代谢。

关键词：一点缀螟肠道细菌可培养细菌高通量测序分析

Effect of Cu on Surface Microcrack of Austenitic Stainless Cold Rolled Coil

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2014年第S1期21卷 56-60页

作者： ji-xiang PAN Guo-yu QIAN Guo-guang chenG Yan LI Wei PAN Zi-bing HOU Chao chen jiuquan Iron and Steel Co. State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

In order to find out the cause of surface microcrack on 304 austenitic stainless cold rolled coils which is produced in a steel plant of China, lots of studies have been carried out. The results indicated that the copper guide of steekle mill used in hot rolling process contacts directly with the hot rolled coil, so parts of copper melt and glued to the surface of the stainless steel plates due to a higher temperature of stainless steel plates than the copper melting temperature, which leads to deterioration of austenitic grain boundaries. Shear stress produced in the process of repeatrolling on finishing mill induces the surface microcracks and promotes it. After changing the copper guide to the cast steel one, such kinds of surface microcracks have never appeared.

关键词： steekle mill austenitic stainless steel surface microcrack copper guide

增温增水情景下钉柱委陵菜物候序列的变化及其抗冻性

在线全文

学校读者我要写书评

暂无评论

植物生态学报 2024年第2期48卷 158-170页

作者：索南吉李博文吕汪汪王文颖拉本陆徐伟宋扎磋陈程浩苗琪孙芳慧汪诗平青海师范大学生命科学学院西宁810016 高原科学与可持续发展研究院西宁810016 青海省青藏高原生物多样性形成机制与综合利用重点实验室西宁810016 青藏高原地球系统资源环境国家重点实验室中国科学院青藏高原研究所北京100101 西藏那曲高寒草地生态系统国家野外科学观测研究站西藏那曲852000 中国科学院大学北京100049 西藏大学拉萨850000

青藏高原正在经历剧烈的气候变化,包括变暖、变湿和极端气候事件频发等,然而,气候变化对高寒植物的影响目前还了解较少。该研究依托西藏那曲高寒草地生态系统野外科学观测研究站,以高寒草甸优势双子叶植物钉柱委陵菜(Potentilla saunder... 详细信息

青藏高原正在经历剧烈的气候变化,包括变暖、变湿和极端气候事件频发等,然而,气候变化对高寒植物的影响目前还了解较少。该研究依托西藏那曲高寒草地生态系统野外科学观测研究站,以高寒草甸优势双子叶植物钉柱委陵菜(Potentilla saundersiana)为研究对象,在2016–2018年设置了不同幅度的增温和降水改变实验,观测了不同处理下6个物候序列的变化,在7个不同极端降温幅度下定量了抗冻性,并计算了2011–2022年生长季的安全裕度。主要结果有:1)增温1℃和2℃以及增水50%对钉柱委陵菜物候序列的影响不显著,只有增温达到4℃时,返青期显著推迟,而初花期显著提前。2)钉柱委陵菜的抗冻性(半致死温度)为(–4.76±4.28)℃,2011–2022年的生长季中34%的月份防止冻害的安全裕度为负值,且大多出现在5月和9月,表明钉柱委陵菜在早春和秋末遭遇极端霜降事件的风险很大。该研究结果揭示了多幅度增温和增水对钉柱委陵菜物候序列的影响,解析了钉柱委陵菜对极端降温事件的抗性,为预测青藏高原高寒植物对未来气候变化的响应提供了数据支撑。

关键词：多幅度增温物候序列极端降温事件抗冻性安全裕度

Expression of long non-coding RNAs in complete transection spinal cord injury: a transcriptomic analysis

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第8期15卷 1560-1567页

作者： Lu ding Wen-jin Fu Hong-Yan di Xiao-Min Zhang Yu-Tian Lei Kang-Zhen chen Tao Wang Hong-Fu Wu Institute of Stem Cells and Regenerative Medicine Department of PhysiologyGuangdong Medical UniversityDongguanGuangdong ProvinceChina Scientific Research Center the Seventh Affiliated Hospital of Sun Yat-Sen UniversityShenzhenGuangdong ProvinceChina Clinical Laboratory Houjie Hospital of Guangdong Medical UniversityDongguanGuangdong ProvinceChina Department of Neurology Dalingshan HospitalDongguanGuangdong ProvinceChina Department of Hand&Foot Surgery Houjie Hospital of Guangdong Medical UniversityDongguanGuangdong ProvinceChina Department of Surgery the Third Hospital of Guangdong Medical University(Longjiang Hospital of Shunde District)FoshanGuangdong ProvinceChina

Long non-coding RNAs(lncRNAs)are abundantly expressed in the central nervous system and exert a critical role in gene regulation via multiple biological *** uncover the functional significance and molecular mechanisms of lncRNAs in spinal cord injury(SCI),the expression signatures of lncRNAs were profiled using RNA sequencing(RNA-seq)technology in a Sprague-Dawley rat model of the 10th thoracic vertebra complete transection *** showed that 116 of 14,802 detected lncRNAs were differentially expressed,among which 16—including eight up-regulated(H19,Vof16,Hmox2-ps1,LOC100910973,Ybx1-ps3,Nnat,Gcgr,LOC680254)and eight down-regulated(Rmrp,Terc,Ngrn,Ppp2r2b,Cox6a2,Rpl37a-ps1,LOC360231,Rpph1)—demonstrated fold changes>2 in response to transection SCI.A subset of these RNA-seq results was validated by quantitative real-time *** levels of 821 mRNAs were also significantly altered post-SCI;592 mRNAs were up-regulated and 229 mRNAs were down-regulated by more than *** Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses showed that differentially expressed mRNAs were related to GO biological processes and molecular functions such as injury and inflammation response,wound repair,and apoptosis,and were significantly enriched in 15 KEGG pathways,including cell phagocytosis,tumor necrosis factor alpha pathway,and leukocyte *** results reveal the expression profiles of lncRNAs and mRNAs in the rat spinal cord of a complete transection model,and these differentially expressed lncRNAs and mRNAs represent potential novel targets for SCI *** suggest that lncRNAs may play an important role in the early immuno-inflammatory response after spinal cord *** study was approved by the Administration Committee of Experimental Animals,Guangdong Province,China.

关键词： cell apotosis complete transection injury high throughput sequencing inflammation ischemia related factor vof-16 long non-coding RNA secondary damage spinal cord TNF signaling transcriptomes

Wettability of different clay mineral surfaces in shale:Implications from molecular dynamics simulations

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2023年第2期20卷 689-704页

作者： Kan-Yuan Shi Jun-Qing chen Xiong-Qi Pang Fu-jie jiang Sha-Sha Hui Zhen-cheng Zhao di chen Qi Cong Tong Wang Hui-Yi Xiao Xiao-Bin Yang Yu-Ying Wang State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China College of Geosciences China University of PetroleumBeijing102249China Basic Research Center for Energy Interdisciplinary College of ScienceChina University of PetroleumBeijing102249China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas College of ScienceChina University of PetroleumBeijing102249China

Shale contains a lot of clay minerals. Clay minerals mainly exist in nano- and micro-meter sized particles, and the pore structure is complex, which leads to its extremely complex wettability. The surface wettability of clay minerals significantly affects the oil and gas-bearing capacity of shale reservoirs. Therefore, studying the wettability of common clay minerals in shale at the nanoscale is of great significance for shale hydrocarbon exploration and development. In this study, the wetting behavior of water in n-hexane and toluene on different clay mineral surfaces at the nanoscale was systematically studied using Molecular dynamics (MD) simulation. And the influencing factors of wettability were analyzed. Through the analysis of the morphological changes of water, relative concentration of water, RDF and interaction energy, it is concluded that the following order of water wettability on the surfaces of clay minerals: montmorillonite > chlorite > kaolinite > illite. Through the analysis of interaction energy, it is concluded that the hydrophilicity of four clay minerals is stronger than that of lipophilicity. And the main interactions between water and oil and the mineral surfaces were van der Waals force and electrostatic force. In addition, the temperature, liquid hydrocarbon type, and mineralization of water affected the wettability of clay minerals. The concentration of water on the surfaces of montmorillonite, kaolinite, and illite decreased with increasing temperature, and the water wettability decreased. At 298 K, the hydrophilicity of the surfaces of the clay minerals in toluene follows the order montmorillonite > chlorite > kaolinite > illite. The higher the NaHCO3 concentration in water, the weaker the wettability of the clay mineral surfaces to water. By comparing the previous experimental results with the MD simulation results, similar wetting characteristics were obtained, and the reliability of the simulation results was verified. MD simulation wa

关键词： Shale Molecular dynamics Nanoscale Wettability Clay minerals

Copper-Catalyzed direct Oxyphosphorylation of Enamides with P（O）-H Compounds and dioxygen

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2017年第9期35卷 1378-1382页

作者： Wu Liang Zhijie Zhang Dong Yi Qiang Fu Suyuan chen Lu Yang Fengtian Du jianxin ji Wei Wei chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan 610041 China University of the Chinese Academy of Sciences Beijing 100049 China School of Chemistry and Chemical Engineering Qufu Normal University Qufu Shandong 273165 China

A simple and convenient copper-catalyzed direct oxyphosphorylation of enamides with P（O）-H compounds and dioxygen has been developed under mild conditions. This methodology can allow the synthesis of a series of valuable β-ketophosphine oxides β-ketophosphonates in moderate to good yields with a broad substrate scope simply by using readily-available starting materials.

关键词： oxyphosphorylation enamides P(O)-H compounds radical reaction dioxygen

战略变革情境中的组织多层级悖论网构建--基于经典扎根理论的研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

管理科学学报 2024年第7期27卷 56-83页

作者：林海芬曲廷琛大连理工大学经济管理学院大连116000 大连理工大学平台治理研究院大连116000

战略变革情境中充斥着各种悖论问题,这些悖论问题相互交错、影响、撬动、传递,形成复杂、混沌的战略变革情境特征,增加了决策者剥离情境探寻制定新战略根源性依据的难度,使得归纳各悖论之间链接规律并系统性刻画战略变革情境成为迫切需... 详细信息

战略变革情境中充斥着各种悖论问题,这些悖论问题相互交错、影响、撬动、传递,形成复杂、混沌的战略变革情境特征,增加了决策者剥离情境探寻制定新战略根源性依据的难度,使得归纳各悖论之间链接规律并系统性刻画战略变革情境成为迫切需求.加上悖论在非变革情境下往往呈隐匿状态,不易被识别,而在战略变革情境中呈凸显状态,容易被识别,因此战略变革情境为系统探究悖论及相互链接关系提供了可能.本研究以十家企业的战略变革数据为样本,采用经典扎根理论和认知地图组成的混合研究方法,从多层级悖论视角分析战略变革情境中的悖论问题,构建组织多层级悖论网模型.研究发现:1)战略变革情境中存在“利益-责任”等18个悖论类型,归属于执行悖论等6种悖论类别,符合“政策导向-需求-目标-方向-价值观-过程”的划分逻辑;2)悖论纵向分布于组织个体层、运营层、战略层、制度层,横向跨越规制、运营、研发、生产、市场五个职能部门,纵横交错,构成组织多层级悖论网的位置形态;3)悖论类型内部由构成悖论四个基本条件的因果或顺次关系构成,同一层级悖论类型之间存在“同层链状顺序”和“同层嵌套”两种关系,跨层级悖论类型之间存在“跨层链状顺序”、“跨层链状共存”和“跨层嵌套”三种关系,构成组织多层级悖论网的关系形态;4)整合组织多层级悖论网的位置形态和关系形态构建组织多层级悖论网模型,系统展示战略变革情境中由悖论的关系和位置构成的复杂状态,表明不同悖论类型之间普遍存在引发性和传递性特征.本研究基于多层级悖论视角,将复杂、混沌的战略变革情境具体化清晰化,为决策者正确认知战略变革情境,准确把握组织困境产生的根源,并做出有效战略决策提供理论参考.

关键词：组织多层级悖论网悖论理论经典扎根理论认知地图战略变革情境

Carbazole alkaloids isolated from the branch and leaf extracts of Clausena lansium

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2018年第7期16卷 509-512页

作者： PENG Wen-Wen ZHENG Li-Xia ji Chang-jiu SHI Xu-Gen XIONG Zhong-Hua SHANGGUAN Xin-chen College of Agriculture Jiangxi Agricultural UniversityNanehang 330045China jiangxi Key Laboratory of Natural Products and Functional Food Jiangxi Agricultural UniversityNanchang 330045China jiangxi Yichun University Yichun 336000China

The present study carried out a phytochemical investigation of the methanol extract of the branches and leaves of Clausena lansium and afforded nine carbazole alkaloids(compounds 1–9) including two new carbazole alkaloids, claulansiums A and B(compounds 1 and 2). The new compounds were elucidated on the basis of extensive spectroscopic data(MS, NMR, IR, and UV) and the known compounds were identified by comparing spectroscopic data with those reported in literature. All the isolated compounds were tested for their cytotoxic activity against A549 and Hela cancer cell lines. Our results showed that compounds 2–6 exhibited varying degrees of cytotoxicity to cancer cells, with IC_(50) values ranging from 8.67 to 98.89 μmol·L^(-1).

关键词： Clausena lansium Carbazole alkaloids Cytotoxic activity

基于SBAS-InSAR技术的高山峡谷区滑坡隐患早期识别

在线全文

学校读者我要写书评

暂无评论

安全与环境工程 2024年第3期31卷 206-216页

作者：陈宏江峻毅纪成亮张伟杨庆义孙旭席文勇张勇刘玉洁李德营国家电力投资集团有限公司安环部北京100029 山东电力工程咨询院有限公司勘测事业部山东济南250100 中国地质大学(武汉)工程学院湖北武汉430074

近年来,高山峡谷区滑坡灾害频发,给人民生命和财产安全带来了严重威胁。滑坡隐患早期识别是高山峡谷区滑坡研究的重点和难点问题之一。以牛栏江中下游河段的象鼻岭水库区域为研究区,基于SBAS-InSAR技术,在分析地形可视性的基础上,通过Se... 详细信息

近年来,高山峡谷区滑坡灾害频发,给人民生命和财产安全带来了严重威胁。滑坡隐患早期识别是高山峡谷区滑坡研究的重点和难点问题之一。以牛栏江中下游河段的象鼻岭水库区域为研究区,基于SBAS-InSAR技术,在分析地形可视性的基础上,通过Sentinel-1A升、降轨数据结合互补的方式,对该区域的滑坡隐患进行早期识别研究。结果表明:升、降轨数据结合有效减小了阴影叠掩区的干扰,能够较全面地识别出高山峡谷区的滑坡隐患点;研究区内雷达视线方向的年平均形变速率为-186~166 mm/a,基于形变结果识别出47个滑坡隐患点;高程在1400~<1600 m、坡度在30°~<40°、坡向在东北和正南方向为滑坡发育的有利地形,大部分滑坡分布在石炭系下统岩关组地层中。研究成果证明了基于SBAS-InSAR技术采用升、降轨数据结合互补方式在高山峡谷区滑坡隐患早期识别中的优势及有效性,具有推广应用的潜力。

关键词：滑坡隐患早期识别高山峡谷区 SARS-InSAR技术地形可视性

维普期刊数据库博看期刊