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Abietane diterpenoids and iridoids from Caryopteris mongolica

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Chinese Journal of Natural Medicines 2023年第12期21卷 927-937页

作者： ZHANG Shanshan MAO Xudong XU Hongtao WEI Xiaohui CHOU guixin Institute of Chinese Materia Medica Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai R&D Center for Standardization of Chinese Medicines Shanghai 201203China State Key Lab of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 201203China

Six new abietane diterpenoids(1−6)and five undescribed iridoids(7−11)have been isolated from the aerial parts of Caryopteris *** intricate structural characterization of these compounds was meticulously undertaken using an array of advanced spectroscopic *** process was further enhanced by the application of DP4+probability analyses and electronic circular dichroism(ECD)*** isolation and structural elucidation,the cytotoxicity of these compounds was *** them,compound 3 stood out,displaying significant cytotoxic activity against HeLa cells with an IC50 value of 7.83±1.28μmol·L^(−1).Additionally,compounds 1,2,4,9,and 10 manifested moderate cytotoxic effects on specific cell lines,with IC50 values ranging from 11.7 to 20.9μmol·L^(−1).

关键词： Caryopteris mongolica Abietane diterpenoids Spectroscopic analysis Cytotoxicity

Soil microbial activity and community structure as affected by exposure to chloride and chloride-sulfate salts

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Journal of Arid Land 2018年第5期10卷 737-749页

作者： ZHANG Qianqian Steven A WAKELIN LIANG Yongchao CHU guixin College of Life Science Shaoxing University Department of Resources and Environmental Science College of Agriculture/the Key Laboratory of Oasis Eco-agriculture of the Xinjiang Production and Construction Corps Shihezi University College of Resources and Environmental Sciences Nanjing Agricultural University Department of Forest Systems Scion Research Ministry of Education Key Laboratory of Environment Remediation and Ecological Health College of Environmental & Resource Sciences Zhejiang University

Mixed or chloride salty ions dominate in saline soils, and exert wide-ranging adversely affect on soil biological processes and soil functions. The objectives of this study were to（1） explore the impacts of mixed（0, 3, 6, 10, 20 and 40 g Cl–/SO42–salt/kg dry soil） and chloride（0, 1.5, 3, 5, 8 and 15 g Cl– salt/kg dry soil） salts on soil enzyme activities, soil physiological functional（Biolog） profiles and microbial community structure by using soil enzymatic, Biolog-Eco microplates as well as denaturing gradient gel electrophoresis（DEEG） methods, and（2） determine the threshold concentration of soil electronic conductivity（EC1：5） on maintaining the functional and structural diversity of soil microbial community. The addition of either Cl– or mixed Cl–/SO42–salt obviously increased soil EC, but adversely affected soil biological activities including soil invertase activity, soil microbial biomass carbon（MBC） and substrate-induced respiration（SIR）. Cl– salt showed a greater deleterious influence than mixed Cl–/SO42–salt on soil enzymes and MBC, e.g., the higher soil MBC consistently appeared with Cl–/SO42–instead of Cl– treated soil. Meanwhile, we found that SIR was more reliable than soil basal respiration（SBR） on explaining the changes of soil biological activity responsive to salt disturbance. In addition, microbial community structures of the soil bacteria, fungi, and Bacillus were obviously affected by both salt types and soil EC levels, and its diversity increased with increasing of mixed Cl–/SO42–salt rates, and then sharply declined down after it reached critical point. Moreover, the diversity of fungal community was more sensitive to the mixed salt addition than other groups. The response of soil physiological profiles（Biolog） followed a dose-response pattern with Cl–（R2=0.83） or mixed Cl–/SO42–（R2=0.89） salt. The critical threshold concentrations of salts for soil physiological function were 0.45 d S/m for Cl– and 1.26 d S/m for Cl–/SO42–, and those for soil

关键词： soil biological activity microbial diversit3T chloride salt mixed salt threshold concentration

3种寄主植物对白刺夜蛾生长发育、繁殖和寿命的影响

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植物保护 2024年第1期50卷 110-115,136页

作者：胡桂馨勾文山马维新孔建宏唐玲孙尧德甘肃农业大学草业学院国家林业和草原局高寒草地鼠害防控工程技术研究中心兰州730070 甘肃省武威市民勤县草原工作站武威733399

白刺夜蛾Leiometopon simyrides是荒漠植物白刺的重要害虫,为明确寄主植物对白刺夜蛾生长发育的影响,以便对其进行科学监测和防控,本研究在27℃下,利用3种寄主植物(大果白刺、泡泡刺、唐古特白刺)饲养白刺夜蛾,观察记录白刺夜蛾幼虫的... 详细信息

白刺夜蛾Leiometopon simyrides是荒漠植物白刺的重要害虫,为明确寄主植物对白刺夜蛾生长发育的影响,以便对其进行科学监测和防控,本研究在27℃下,利用3种寄主植物(大果白刺、泡泡刺、唐古特白刺)饲养白刺夜蛾,观察记录白刺夜蛾幼虫的取食量、各阶段的发育历期、存活率、羽化率、雌雄性比和成虫寿命等生物学特性,同时测定各寄主植物叶片的营养和次生代谢物质含量。结果表明,白刺夜蛾幼虫取食大果白刺叶片的总量最少,取食唐古特白刺的量最多。取食唐古特白刺的白刺夜蛾幼虫发育历期最短,其次为取食泡泡刺,取食大果白刺时历期最长。取食泡泡刺和唐古特白刺后,白刺夜蛾幼虫的存活率和羽化率较高,取食大果白刺存活率最低,且无成虫羽化。在唐古特白刺上,白刺夜蛾雌虫占比较高,成虫寿命较长。大果白刺的叶片总酚含量和简单酚含量最高,各营养物质含量最低,不利于白刺夜蛾的生长发育;唐古特白刺和泡泡刺酚类物质含量较低,营养物质含量较高,较适宜白刺夜蛾的生长发育和繁殖。唐古特白刺为白刺夜蛾的最适宜寄主植物,其次为泡泡刺。

关键词：白刺白刺夜蛾生长发育取食量营养物质次生代谢物质

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深埋竖井高富水层高压旋喷止水帷幕施工技术

中国水能及电气化 2024年第4期 12-17,39页

作者：王梓任乔桂鑫张路明北京金河水务建设集团有限公司北京102206

富水砂层竖井倒挂井壁法施工时,受地下水影响,施工过程中会出现涌砂涌水现象,给竖井施工安全带来巨大风险。文章以南水北调配套工程大兴支线施工十三标段为例,通过采用高压旋喷桩旋喷套接的施工方式,将桩体插入井底以下相对不透水层,形... 详细信息

富水砂层竖井倒挂井壁法施工时,受地下水影响,施工过程中会出现涌砂涌水现象,给竖井施工安全带来巨大风险。文章以南水北调配套工程大兴支线施工十三标段为例,通过采用高压旋喷桩旋喷套接的施工方式,将桩体插入井底以下相对不透水层,形成竖井周边封闭的止水帷幕。实施该技术后,成功解决了竖井施工中出现井壁流水流砂、井底涌水涌砂、井边地面塌陷及开挖支护困难等安全问题。文章总结了富水砂层竖井高压旋喷桩止水帷幕施工技术要点,供类似工程借鉴和参考。

关键词：富水砂层高压旋喷桩止水帷幕

Giant enhancement of second-harmonic generation from a nanocavity metasurface

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Science China(Physics,Mechanics & Astronomy) 2021年第9期64卷 75-81页

作者： Xuecai Zhang Junhong Deng Mingke Jin yang Li Ningbin Mao Yutao Tang Xuan Liu Wenfeng Cai Yao Wang Kingfai Li Yanjun Liu guixin Li Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China Materials Characterization and Preparation Center Southern University of Science and TechnologyShenzhen 518055China

Nonlinear plasmonic metasurfaces are compatible with complementary metal oxide semiconductor technology and highly promising for on-chip optical switching and modulations and nanoscale frequency ***,the low nonlinearoptical response of metasurface devices limits their practical *** circumvent this constraint,we propose the design of a nanocavity plasmonic metasurface,in which the strong light localization in the nanocavity can be used to boost the efficiency of second-harmonic *** with the single-layer counterpart,experimental results show that the intensity of the second-harmonic waves in the nanocavity metasurface is enhanced by~790 *** proposed nanocavity plasmonic metasurfaces in this work may open new routes for developing highly efficient nonlinear metacrystals for on-chip nonlinear sources,nonlinear image encryption,information processing,and so on.

关键词： metamaterials nonlinear optics nanostructures

某顶部楼层竖向收进的超限高层建筑结构抗震性能分析

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山西建筑 2024年第21期50卷 59-62页

作者：施尽波黄桂新练有为深圳市东大国际工程设计有限公司广东深圳518042

结合某顶部楼层竖向收进的超限高层建筑结构,首先分析了结构在小震和风荷载作用下的各项指标;其次采用弹性时程补充分析了顶部楼层竖向收进后的地震放大效应;再次对竖向收进前后框架柱受力重分布、收进区域楼板应力进行了重点分析;最后... 详细信息

结合某顶部楼层竖向收进的超限高层建筑结构,首先分析了结构在小震和风荷载作用下的各项指标;其次采用弹性时程补充分析了顶部楼层竖向收进后的地震放大效应;再次对竖向收进前后框架柱受力重分布、收进区域楼板应力进行了重点分析;最后采用大震弹塑性时程分析方法验算了结构薄弱层层间塑性位移角。分析结果表明:顶部楼层竖向收进后,楼层地震动反应增大较为明显,当采用振型分解反应谱法设计时,应对顶部收进后楼层地震力予以放大,并对收进后的楼层采用弹性动力时程补充验算层间位移角是否满足规范要求;对于顶部框架局部竖向收进结构,在水平荷载作用下,刚度相对较大的未收进框架在收进上两层可能存在内力突变,需要进行特别加强;体型收进部位上、下层结构的楼板均应加厚并加强配筋。

关键词：局部收进超限高层结构弹性时程分析受力重分布弹塑性时程分析

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落实四个回归一流本科专业建设探究

中国中医药现代远程教育 2024年第6期22卷 177-181页

作者：鞠文雪尚东林敏隋华张桂信杨琦姚娓大连医科大学附属第二医院中医科辽宁大连116023 大连医科大学中西医结合学院/研究院辽宁大连116044 大连医科大学附属第一医院普外科辽宁大连116023

基于一流本科专业背景,国家全面实施“六卓越一拔尖”计划2.0,启动一流本科专业建设“双万计划”,各大高校开展了教育改革的探索和实践。此文以大连医科大学中西医结合学院教育教学改革研究为例,从“四个回归”着手,围绕人才培养制度、... 详细信息

基于一流本科专业背景,国家全面实施“六卓越一拔尖”计划2.0,启动一流本科专业建设“双万计划”,各大高校开展了教育改革的探索和实践。此文以大连医科大学中西医结合学院教育教学改革研究为例,从“四个回归”着手,围绕人才培养制度、人才培养定位和目标、人才培养教学平台、教师队伍和教育保障机制5个方面构建中西医临床医学专业一流本科教育人才培养体系,推动教学管理和教学质量的提升,进一步探索如何实施一流本科教育的建设路径这一迫切问题。

关键词：一流本科专业教学改革复合应用型人才中西医临床医学专业

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基于麻雀搜索算法的涡喷发动机控制研究

广西大学学报（自然科学版） 2024年第3期49卷 553-562页

作者：梁建国黄豪中龙回归雷柏钧陈桂薪广西大学机械工程学院广西南宁530004

为了改善微型涡喷发动机的控制性能,针对传统比例积分微分(PID)控制器难以进行在线调参和参数优化的问题,提出了一种基于麻雀搜索算法(SSA)的控制方法。首先,利用实验获取的涡喷发动机数据进行系统辨识,建立涡喷发动机的数学模型;其次,... 详细信息

为了改善微型涡喷发动机的控制性能,针对传统比例积分微分(PID)控制器难以进行在线调参和参数优化的问题,提出了一种基于麻雀搜索算法(SSA)的控制方法。首先,利用实验获取的涡喷发动机数据进行系统辨识,建立涡喷发动机的数学模型;其次,采用模糊控制设计了模糊PID控制器;最后,利用SSA对模糊PID控制器的参数进行优化。仿真结果表明:基于SSA的模糊PID控制方法在涡喷发动机转速控制系统中性能显著提升,上升时间为0.22 s,超调量为8.02%,干扰调整时间为1.05 s。相较于传统PID和模糊PID控制方法,该方法的响应速度分别提高了64.1%和43.9%,超调量分别减少了18.08%和7.58%,干扰调整时间分别缩短了52.3%和34.4%。

关键词：控制系统麻雀搜索算法模糊控制涡喷发动机数学建模

The pathogenicity on legumes of Cucumber mosaic virus was determined by 243 nucleotides on 2a polymerase gene of viral RNA2

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Chinese Science Bulletin 2002年第9期47卷 748-750,794页

作者： TAO Xiaorong ZHOU Xueping LI guixin YU Jialin Institute of Biotechnology Zhejiang UniversityHangzhou 310029China National Key Laboratory on Agrobiotechnology China Agriculture UniversityBeijing 100094China

We had isolated and identified two Cucumber mosaic virus (CMV) isolates, the CMV red bean (CMV-RB) isolate and the CMV pea (CMV-P1) isolate. CMV-RB induces necrotic local lesions on inoculated leaves of broad bean, pea, cowpea and bean, and could not infect these hosts systemically. However, CMV-P1 was able to infect these legumes systemically. To study the difference of pathogenic-ity on the legumes induced by these two CMV isolates, the full-length infectious cDNA clones of CMV-Fny, which induced similar symptoms as CMV-RB in the four legumes, were used. The 243 nucleotides fragment, which encodes highly conserved GDD amino acid motif on 2a replicase gene of CMV-Fny RNA2, was replaced with that of CMV-P1. The constructed chimeric virus FP could infect these legumes systemically. The exchange of this region changes the virus symptoms on the legumes, indicating that this 243 nucleotides fragment has major effect on pathogenicity of CMV on the legumes.

关键词： Cucumber mosaic virus legumes replicase gene patho-genicity.