检索结果-南通市图书馆

维普期刊数据库博看期刊

在线全文

学校读者我要写书评

暂无评论

推-拉技术对松材线虫病防控效果研究

生物灾害科学 2024年第2期47卷 243-248页

作者：江雪峰陈凤毛柴演初徐明许嘉麟柴忠心休宁县林业有害生物防治检疫站安徽黄山245499 南京林业大学南方现代林业协同创新中心江苏南京210037 江苏省林业科学研究院江苏南京210053 南京生兴有害生物防治技术股份有限公司江苏南京211112

【目的】在林间连年设置6种引诱剂和5种驱避剂,使用推-拉技术,比较和实现其对松褐天牛成虫和松材线虫病的防控效果。【方法】拟利用课题组开发的驱避剂和引诱剂,把松褐天牛成虫驱赶(推)到适当位置,再用引诱剂(拉)集中消灭,大量诱杀松褐... 详细信息

【目的】在林间连年设置6种引诱剂和5种驱避剂,使用推-拉技术,比较和实现其对松褐天牛成虫和松材线虫病的防控效果。【方法】拟利用课题组开发的驱避剂和引诱剂,把松褐天牛成虫驱赶(推)到适当位置,再用引诱剂(拉)集中消灭,大量诱杀松褐天牛及其携带的病原松材线虫,实现对松材线虫病的精准防控,保护松树免受其危害。【结果】复配引诱剂SY1和SY4对林间松褐天牛成虫的引诱效果最好,且无显著差异,引诱率分别达64.41%和66.29%。2019—2021年使用的复配驱避剂对天牛成虫的林间驱避率分别为81.82%、73.74%和74.30%,显著高于单剂的驱避效果(53.85%、60.75%和61.70%,F0.01=11.3),说明复配驱避剂对松褐天牛成虫有显著的林间驱避效果。随着林间连年使用复配驱避剂把松褐天牛驱赶(推)到一定区域,驱避剂挂设点20 m外东南西北四向的引诱剂诱捕器诱捕(拉)大量天牛成虫,同时结合连年彻底清理病死树,使3年的驱避剂点外平均每诱捕器诱捕松褐天牛成虫数分别为(149.33±19.43)、(23.88±5.52)和(7.17±2.00)头,林间天牛成虫的虫口密度大幅降低。林间松树平均病死率逐年降低,分别为(12.70±3.20)%、(7.30±2.40)%和(5.30±2.20)%。【结论】通过林间推-拉技术的成功实施,大量诱杀了林间松褐天牛成虫,减少了病害的传播原,大幅降低林间的病死树率,实现了对松材线虫病的有效防控。

关键词：松褐天牛松材线虫病推-拉技术引诱剂驱避剂

Obesity and colorectal cancer risk: A meta-analysis of cohort studies

在线全文

学校读者我要写书评

暂无评论

World Journal of gastroenterology 2007年第31期13卷 4199-4206页

作者： Zhe Dai Yan-Cheng xu Li Niu DepartmentofEndocrinology ZhongnanHospitalWuhanUniversityWuhan430071HubeiProvinceChina

TO evaluate the association between obesity and colorectal cancer risk. METHODS： We searched PubMed, EMBASE, and the cochrane Library up to January 1, 2007. cohort studies permitting the assessment of causal association between obesity and colorectal cancer, with clear definition of obesity and well-defined outcome of colorectal cancer were eligible. Study design, sample size at baseline, mean follow-up time, co-activators and study results were extracted. Pooled standardized effect sizes were calculated.

关键词： Obesity colorectal cancer Waist-to-hipratio Waist circumference Weight cohort study Metaanalysis

脑电双频谱指数指导下七氟烷吸入复合静脉麻醉对老年股骨颈骨折患者应激反应、苏醒质量及认知功能的影响

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

老年医学与保健 2024年第4期30卷 1135-1139页

作者：肖兵周峰强徐仁毅江油市人民医院麻醉科四川江油621700

目的观察脑电双频谱指数(BIS)指导下七氟烷吸入复合静脉麻醉对老年股骨颈骨折患者应激反应、苏醒质量及认知功能的影响。方法回顾性分析2022年1月—2024年3月在江油市人民医院行人工髋关节置换术的113例老年股骨颈骨折患者临床资料,根... 详细信息

目的观察脑电双频谱指数(BIS)指导下七氟烷吸入复合静脉麻醉对老年股骨颈骨折患者应激反应、苏醒质量及认知功能的影响。方法回顾性分析2022年1月—2024年3月在江油市人民医院行人工髋关节置换术的113例老年股骨颈骨折患者临床资料,根据麻醉方案分为对照组(n=53,BIS指导下全凭静脉麻醉)和观察组(n=60,BIS指导下七氟烷吸入复合静脉麻醉)。比较2组应激反应[收缩压(SBP)、舒张压(DBP)、心率(HR)、皮质醇(cor)水平、丙二醛(MDA)水平]、苏醒质量(自主呼吸恢复时间、定向力恢复时间、苏醒时间)、认知功能、视觉模拟评分(VAS法)及并发症发生情况。结果2组插管即刻(T1)、切皮后10 min(T2)、手术结束时(T3)的SBP、DBP、HR较麻醉诱导前(T0)降低(均Pcor、MDA水平较术前升高,但观察组术后即刻、术后24 h、术后72 h的cor、MDA水平显著低于对照组,差异均有统计学意义(均P0.05)。结论BIS指导下七氟烷吸入复合静脉麻醉可减轻老年股骨颈骨折手术患者术中应激反应,提高苏醒质量,改善术后认知功能,缓解术后疼痛,具有一定的临床应用价值。

关键词：老年股骨颈骨折脑电双频谱指数七氟烷静脉麻醉应激反应苏醒质量认知功能

color-tunable circularly polarized electroluminescence from a helical chiral multiple resonance emitter with B–N bonds

在线全文

学校读者我要写书评

暂无评论

中国科学:化学英文版 2023年第9期66卷 2612-2620页

作者： Li Yuan Zhen-Long Tu Jun-Wei xu Hua-Xiu Ni Zhi-Ping Mao Wen-Ye xu You-xuan Zheng State Key Laboratory of coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Shenzhen Institute of Information Technology Shenzhen 518172China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China guangzhou Research&Creativity Biotechnology co.Ltd. Guangzhou 510700China

Chiral B,N-doped polycyclic aromatic hydrocarbons with circularly polarized luminescence(CPL) and small full-width at halfmaxima(FWHM) are promising multiple resonance(MR) emitters for CP organic light-emitting diodes(CP-OLEDs).This work presents a pair of chiral MR enantiomers,P/M-o[B-N]_(2)N_(2),featuring B–N bonds incorporated within a[7]-helicene *** enantiomers exhibit narrow 0-0 and 0-1 electronic transition bands,whose relative intensity can be fine-tuned by increasing doping concentrations,resulting in redshifts of the emission peak from 542 to 592 *** enantiomers show mirrorsymmetric CPL spectra with an asymmetry factor(|g_(PL)|) of 1.0×10^(-3).The hyperfluorescent CP-OLEDs with double-sensitized emitting layers display a FWHM of 33 nm,an external quantum efficiency of 25.1%,and a|g_(EL)|factor of 7.7×10^(-4).Notably,the CP-OLEDs realize color-tunable CP electroluminescence peak from 553 to 613 nm by regulating the vibrational *** work provides a novel concept for the design of helical CP-MR materials and CP-OLEDs,highlighting their potential for future applications in advanced optoelectronic devices.

关键词： chiral multiple resonance material helical chirality circularly polarized luminescence narrowband emission color-tunable circularly polarized electroluminescence

同方期刊数据库

ReaxFF molecular dynamic simulation of primary and secondary reactions involving in sub-bituminous coal pyrolysis for tar production

在线全文

学校读者我要写书评

暂无评论

Carbon Resources conversion 2021年第1期4卷 230-238页

作者： Yanan Qian Jin-Hui Zhan Wei xu Zhennan Han Xiaoxing Liu guangwen xu State Key Laboratory of Safety and control for Chemicals SINOPEC Research Institute of Safety Engineering Co.Ltd.Qingdao 266071China State Key Laboratory of Multiphase complex System Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Key Laboratory on Resources Chemicals and Materials of Ministry of Education of China Shenyang University of Chemical TechnologyShenyang 110142China

ReaxFF molecular dynamic simulation combined with experimental verification was performed to understand the overall reaction mechanism,especially the primary and secondary reactions involving in tar formation of sub-bituminous coal *** relationship at atomic level is clarified between bond breakage of functional groups and products generation,revealing that the amount and order in forming each product are subject to the number of corresponding functional groups and their bond energies *** primary breakage of-C-O-and-C-C-bridge-bonds present in initial coal macromolecular generates molecular of heavy tar,whereas heavy tar can be converted into light tar through cracking side chain of aromatic rings and cyclic hydrocarbons at increased pyrolysis *** very high temperatures the cracking of short-chain hydrocarbons and residual atoms connecting to aromatic rings further occurs to generate light tar and *** remaining aromatic-ring fragments of heavy tar are likely cross-linked to form ***,the simultaneous evolution tendency of tar yield and tar quality under different pyrolysis temperatures and heating rates is obtained at molecular *** obtaining high yield and quality of tar,appropriately high temperature as well as suitable heating rate are needed to compromise the high yield of primary tar and high quality of secondarily upgraded products.

关键词： ReaxFF MD simulation Sub-bituminous coal pyrolysis Reaction paths Primary formation Secondary upgrading

Mixed convection heat transfer in horizontal channel filled with nanofluids

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

Applied Mathematics and Mechanics(English Edition) 2013年第3期34卷 339-350页

作者： Tao FAN Hang xu I. POP State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 P. R. China Post-Doctoral Research Station Jiangnan Shipyard Group Co. Ltd. Shanghai 201913 P. R. China Department of Mathematics Babes-Bolyai University Cluj-Napoca R-400084 Romania

The laminar fully developed nanofluid flow and heat transfer in a horizonal channel are investigated. Highly accurate solutions for the temperature and nanopavticle concentration distributions are obtained. The effects of the Brownian motion parameter Nb, the thermophoresis parameter Nt, and the Lewis number Le on the temperature and nanoparticle concentration distributions are discussed. The current analysis shows that the nanoparticles can improve the heat transfer characteristics significantly for this flow problem.

关键词： nanofluid flow horizontal channel mixed convection heat transfer,homotopy analysis method (HAM)

在线全文

学校读者我要写书评

暂无评论

光伏新能源并网对继电保护的影响分析

科学技术创新 2024年第22期 125-128页

作者：胡永伟徐超张峰中电建新能源集团股份有限公司华东分公司浙江杭州中电建新能源集团股份有限公司甘肃分公司甘肃兰州

我国建设光伏电站规模扩大,更多光伏电站并网,由于短路电流流向、分布与原有配电网不同,对继电保护造成影响,降低配网运行稳定性。为此,文章简要阐述了光伏新能源并网电流助增与电流分流特点,从光伏并网接入位置与并网容量两方面出发,... 详细信息

我国建设光伏电站规模扩大,更多光伏电站并网,由于短路电流流向、分布与原有配电网不同,对继电保护造成影响,降低配网运行稳定性。为此,文章简要阐述了光伏新能源并网电流助增与电流分流特点,从光伏并网接入位置与并网容量两方面出发,分析光伏新能源并网对继电保护的影响,并提出继电保护改进方案,以期为相关工作者提供参考。

关键词：光伏能源新能源并网继电保护影响

Effect of Ca promoter on LPg synthesis from syngas over hybrid catalyst

在线全文

学校读者我要写书评

暂无评论

Journal of Natural gas Chemistry 2012年第6期21卷 615-619页

作者： Xiangang Ma Qingjie ge Chuanyan Fang Hengyong xu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Direct synthesis of liquefied petroleum gas （LPg） from syngas was carried out over hybrid catalyst consisting of methanol synthesis catalyst and modified Y zeolite with Pd and Ca by different methods. The decrease of co conversion was mostly attributable to the sintering of Cu in methanol synthesis catalyst. On the other hand, coke deposition on Y zeolite was the reason for the decrease of LPg selectivity. The introduction of Ca decreased the strong acid sites of Y zeolite, suppressed coke formation, and thus improved the stability of hybrid catalyst.

关键词： liquefied petroleum gas calcium Y zeolite coke deposition coke burning

在线全文

学校读者我要写书评

暂无评论

异步挂篮在波形钢腹板桥梁施工中的受力分析

云南水力发电 2024年第9期40卷 110-113页

作者：郭永芳徐文强中国水利水电第十四工程局有限公司云南昆明650041

为进一步推广波形钢腹板异步挂篮应用范围,以漳河大桥主桥波形钢腹板变截面预应力混凝土连续梁异步挂篮施工为研究对象,对新型异步挂篮在波形钢腹板桥梁悬臂浇筑施工方法中挂篮各构件受力最不利条件进行受力模拟研究,介绍了该施工方法... 详细信息

为进一步推广波形钢腹板异步挂篮应用范围,以漳河大桥主桥波形钢腹板变截面预应力混凝土连续梁异步挂篮施工为研究对象,对新型异步挂篮在波形钢腹板桥梁悬臂浇筑施工方法中挂篮各构件受力最不利条件进行受力模拟研究,介绍了该施工方法中挂篮结构形式、主要性能参数及特点、挂篮设计,并通过有限元对挂篮整个空间的内力进行了分析,采用部分系数设计表达式计算极限状态。结果表明,挂篮结构形式简单、主要技术参数适用性强、挂篮设计受力变形合理。异步挂篮较传统挂篮重量轻,具有良好的社会经济效益。

关键词：漳河大桥异步挂篮波形钢腹板受力分析