检索结果-南通市图书馆

Dynamic synthetic analysis of circulation field of tropical cyclones affecting Shanghai

Frontiers of Earth Science 2024年第2期18卷 347-363页

作者： Wen GU Caijun YUE Zhihui HAN yanqing gao Yuqi TANG Xiangyu AO Yao YAO Shanghai Ecological Forecasting&Remote Sensing Center Shanghai 200030China Shanghai Marine Meteorological Centre Shanghai 200030China Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030China Key Laboratory of Numerical Modeling for Tropical Cyclone(China Meteorological Administration) Shanghai 200030China

Eleven tropical cyclones(TCs)affected Shanghai and crossed the same latitude as Shanghai from 2007 to *** to similar tracks from best-track data,TCs that cause significant precipitation in Shanghai can be divided into three types:landfall TCs,nearshore northward TCs,and western *** on ERA5 reanalysis data,the dynamic synthesis method was used to synthesize TC circulation situations to compare thermal,dynamic,water vapor,and stability conditions within TC circulations during the period when they affected *** conclusions are as follows.1)When the three TC types are at the same latitude as Shanghai,they are all in the divergent field in the upper *** the landfall type,the subtropical high at 500 hPa is stronger and farther north than usual,and there is a high-pressure dam on the north side of the TCs.2)The warm advection of the three TC types at 925 hPa is located in the northern quadrant of the *** dynamic and water vapor conditions are good in the north-western quadrant of landfall and western TCs,and more favorable in the eastern quadrant of nearshore northward TCs.3)The favorable effects of all three types on precipitation in Shanghai come from the boundary *** vapor,upward motion,and instability conditions of landfall TCs are superior to the other two TC *** best water vapor,dynamic,and convective instability conditions are at the northern boundary in Shanghai during landfall TCs,and the main sources of water vapor in Shanghai come from the eastern and northern *** nearshore northward TCs,the main contribution to precipitation is from the eastern boundary,while better dynamic and water vapor conditions come from the western and northern boundaries during western *** above findings provide scientific and technical support for operational forecasting precipitation from TCs affecting mega-cities.

关键词： tropical cyclones dynamic synthetic analysis ERA5 reanalysis Shanghai similar track

来源：

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

Convection Initiation of a Heavy Rainfall Event in the Coastal Metropolitan Region of Shanghai on the South Side of the Meiyu Front

引用

Journal of Meteorological Research 2023年第2期37卷 149-173页

作者： yanqing gao Xiaofeng WANG Ying XIE Wen GU Shanghai Ecological Forecasting and Remote Sensing Center Shanghai 200030

Accurate prediction of the convection initiation(CI)in urban areas is still a challenge.A heavy rainfall event,missed by the 9-km regional operational modeling system,occurred in the coastal urban area of the Shanghai metropolitan region(SMR)in the late morning on 28 July 2020 on the warm side to the south of the Meiyu *** this study,observational analyses and convection-permitting simulations with a resolution of 3 km were conducted to investigate the CI mechanism of this rainfall *** results showed that the CI was due to the interaction of urban heat island(UHI),northwesterly outflows from the Meiyu front precipitation system(MFPS),and northeasterly sea ***,the UHI created a lifting condition producing adiabatic cooling and the vertical moisture transport in the urban ***,the mesolow generated by the UHI induced and enhanced local low-level convergence near the CI region and accelerated the northwesterly outflows and the northeasterly sea winds as they converged to the *** convection was triggered as a result of the strengthened low-level convergence when the enhanced northwesterly outflows and northeasterly sea winds approached the updraft zone caused by the UHI *** experiments with either the urban area of the SMR removed or the MFPS suppressed further revealed that the enhancement of the low-level convergence was mainly contributed by the *** outflows and sea winds transported cold and moist air to the CI region and partly offset the negative contribution of the urban drying effect to the low-level relative humidity to facilitate the development of the deep moist absolute unstable layer during the *** addition,the MFPS also contributed to the enhancement of the northeasterly sea winds by influencing the land–sea pressure contrast on the north of the SMR.

关键词： convection initiation urban heat island outflows Meiyu front precipitation system heavy rainfall

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

On Frequency Sensitivity and Mode Orthogonality of Flexible Robotic Manipulators

引用

IEEE/CAA Journal of Automatica Sinica 2016年第4期3卷 394-397页

作者： Fei-Yue Wang yanqing gao IEEE State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences Research Center of Computational Experiments and Parallel Systems the National University of Defense Technology Department of Manufacturing & Mechanical Engineering & Technology Oregon Institute of Technology

This paper presents sensitivity analysis of vibration frequencies of flexible manipulators with respect to variations of systems parameters such as rotational inertia of hub, and mass, moment, and side of tip load. Both Euler-Bernoulli and Timoshenko dynamical models of flexible manipulators are discussed. By using variational method, sensitivity indices are obtained with explicit expressions for measuring the sensitivity of frequencies. Based on variational formulations, a novel method for deriving the orthogonal relations among vibration modal shape functions of flexible manipulators is introduced. With this method, the orthogonal relations can be derived easily without invoking the tedious process of differentiation and integration by part, as commonly used in their derivation. © 2014 Chinese Association of Automation.

关键词： Dielectric waveguides Flexible manipulators Manipulators Orthogonal functions Vibration analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Magnetic properties and structure of Ni_80Fe_20/Ni_48Fe_12Cr_40 bilayer films deposited on SiO_2/Si(100) by electron beam evaporation

引用

Rare Metals 2007年第2期26卷 176-181页

作者： WU Ping gao yanqing QIU Hong PAN Liqing TIAN Yue Wang Fengping Department of Physics University of Science and Technology Beijing Beijing 100083 China

Ni80Fe20/Ni48Fe12Cr40 bilayer films and Ni80Fe20 monolayer films were deposited at room temperature on SiO2/Si（100） substrates by electron beam evaporation. The influence of the thickness of the Ni48Fe12Cr40 underlayer on the structure, magnetization, and magnetoresistance of the Ni80Fe20/Ni48Fe12Cr40 bilayer film was investigated. The thickness of the Ni48Fe12Cr40 layer varied from about 1 nm to 18 nm while the Ni80Fe20 layer thickness was fixed at 45 nm. For the as-deposited bilayer films the introducing of the Ni48Fe12Cr40 underlayer promotes both the （111） texture and grain growth in the Ni80Fe20 layer. The Ni48Fe12Cr40 underlayer has no significant influence on the magnetic moment of the Ni80Fe20/Ni48Fe12Cr40 bilayer film. However, the coercivity of the bilayer film changes with the thickness of the Ni48Fe12Cr40 undedayer. The optimum thickness of the Ni48Fe12Cr40 underlayer for improving the anisotropic magnetoresistance effect of the Ni80Fe20/Ni48Fe12Cr40 bilayer film is about 5 nm. With a decrease in temperature from 300 K to 81 K, the anisotropic magnetoresistance ratio of the Ni80Fe20 （45 nm）/Ni48Fe12Cr40 （5 nm） bilayer film increases linearly from 2.1% to 4.8% compared with that of the Ni80Fe20 monolayer film from 1.7% to 4.0%.

关键词： Ni80Fe20 films Ni48Fe12Cr4o seed layer structure magnetic properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deviation Inequality for the Number of k-Cycles in a Random Graph

引用

Wuhan University Journal of Natural Sciences 2009年第1期14卷 11-13页

作者： WANG yanqing gao Fuqing School of Mathematics and Statistics Wuhan UniversityWuhan 430072 Hubei China

We study the number of k-cycles in a random graph G（n, p）. We estimate the probability that a random graph contains more k-cycles than expected. In this case, the usual martingale inequality with bounded difference is not effective. By construct- ing a variable that approximates to the number of k-cycles in a random graph and using a new and extensive martingale inequality, we get the results in this paper.

关键词： random graph deviation inequality k-cycles

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

硅油取出联合巩膜扣带术对预防视网膜再脱离的疗效分析

引用

实用防盲技术 2024年第3期19卷 93-96页

作者：刘晓丹任雁鹏高延庆郑州市第二人民医院眼科河南郑州450000

目的评估硅油取出术中联合巩膜扣带术在预防前部增殖性玻璃体视网膜病变(PVR)或视网膜裂孔患者硅油取出术后视网膜再脱离的疗效分析。方法回顾性分析2021年1月-2023年1月在我院诊治的43例前部增殖性玻璃体视网膜病变患者(43只眼),均为... 详细信息

目的评估硅油取出术中联合巩膜扣带术在预防前部增殖性玻璃体视网膜病变(PVR)或视网膜裂孔患者硅油取出术后视网膜再脱离的疗效分析。方法回顾性分析2021年1月-2023年1月在我院诊治的43例前部增殖性玻璃体视网膜病变患者(43只眼),均为玻切联合硅油填充术后3个月取硅油患者。术前经过三面镜检查,发现赤道前存在增殖性玻璃体视网膜病变(PVR)、新发网膜裂孔,术中光导直视下检查并定位PVR、裂孔位置,行巩膜外垫压或环扎术,并取出眼内硅油,手术后随访患者3个月,观察硅油取出术中联合巩膜扣带术对视网膜再脱离的预防疗效。结果视网膜复位率95.35%(41/43),术后3个月末患者视力视力指数>0.1者44.19%(19/43),0.06-0.1者51.16%(22/43),指数≤0.05者4.65%(2/43)优于术前的指数>0.1者25.58%(11/43),0.06-0.1者62.79%(27/43),指数≤0.05者11.63%(5/43),差异有统计学意义(U=1.9609,P=0.0499<0.05),所有患者均未出现明显并发症。结论对于存在前部PVR、赤道前视网膜裂孔的眼内硅油填充患者,行硅油取出术中联合巩膜扣带手术,视网膜复位效果良好且有利于患者术后视力的有效恢复。

关键词：硅油取出巩膜扣带术视网膜再脱离疗效分析

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Impulse Transient Characteristic of Grounding Grids

Impulse Transient Characteristic of Grounding Grids

引用

2002 3rd International Symposium on Electromagnetic Compatibility

作者： gao yanqing HE Jinliang ZENG Rong LIANG Xidong Dept.of Electrical Engineering Tsinghua University

ISBN: (纸本)0780372778

＜正＞The lightning transient characteristic of a grounding grid for substation is analyzed in detail,which especially considers the dynamic and nonlinear effects of soil ionization around grounding conductors and the inductance between grounding *** analysis results are calculated by a loss transmission-line model with distributed time-variable *** influences of structure of the grid,location of feed point,and shape of the lightning impulse current on the transient characteristic of grounding grids are discussed.

关键词： transient characteristic grounding grid lightning loss transmission line

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

桧木醇酯类衍生物的设计合成及抑菌活性

引用

农药学学报 2024年第3期26卷 462-471页

作者：叶久辉桂阔殷妮刘新李璇雷鹏冯俊涛马志卿高艳清西北农林科技大学植物保护学院陕西省生物农药工程技术研究中心陕西杨凌712100

为了丰富天然单萜桧木醇的结构多样性、拓宽其活性范围,在前期研究的基础上,以桧木醇为先导化合物,设计并合成了15个新型桧木醇羧酸酯类化合物(3)以及20个桧木醇磺酸酯类化合物(异构体5和6)。抑菌活性测定结果表明,大部分目标化合物在50... 详细信息

为了丰富天然单萜桧木醇的结构多样性、拓宽其活性范围,在前期研究的基础上,以桧木醇为先导化合物,设计并合成了15个新型桧木醇羧酸酯类化合物(3)以及20个桧木醇磺酸酯类化合物(异构体5和6)。抑菌活性测定结果表明,大部分目标化合物在50μg/mL下对苹果树腐烂病菌Valsa mali、水稻纹枯病菌Rhizoctonia solani、番茄灰霉病菌Botrytis cinerea及黄瓜炭疽病菌Colletotrichum orbiculare均表现出良好的抑菌活性,其中羧酸酯类衍生物3a、3f、3g、3o对水稻纹枯病菌的EC50值分别为0.96、1.05、1.29和1.88μg/mL,3a、3e、3j对苹果树腐烂病菌的EC50值分别为3.60、3.28和3.48μg/mL,3d、3f、3g对黄瓜炭疽病菌的EC50值分别为0.77、0.51和0.67μg/mL,均优于桧木醇。总体来说,羧酸酯类衍生物的抑菌活性明显优于磺酸酯类衍生物,但磺酸酯类衍生物酯基位置的异构体抑菌活性存在较大差异,构型为1时抑菌活性更好。

关键词：桧木醇抑菌活性苹果树腐烂病菌水稻纹枯病菌黄瓜炭疽病菌

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

中空介孔二氧化硅负载戊唑醇纳米缓释颗粒的制备及生物活性

引用

农药学学报 2024年第3期26卷 559-569页

作者：桂阔周瑞惠托平刘夷宁张欣茹李文奎雷鹏高艳清马志卿西北农林科技大学植物保护学院陕西杨凌712100 陕西省生物农药工程技术研究中心陕西杨凌712100

本研究以中空介孔纳米二氧化硅(hollow mesoporous nano silica, HMS)为载体负载戊唑醇(tebuconazole, Teb),制备了戊唑醇@中空介孔纳米二氧化硅(Teb@HMS)缓释颗粒。通过扫描电镜(SEM)、透射电镜(TEM)、傅立叶变换红外光谱仪(FTIR)、比... 详细信息

本研究以中空介孔纳米二氧化硅(hollow mesoporous nano silica, HMS)为载体负载戊唑醇(tebuconazole, Teb),制备了戊唑醇@中空介孔纳米二氧化硅(Teb@HMS)缓释颗粒。通过扫描电镜(SEM)、透射电镜(TEM)、傅立叶变换红外光谱仪(FTIR)、比表面积分析仪(BET)及热重分析仪(TGA)等仪器对其形貌、结构与性能进行了表征。通过高效液相色谱(HPLC)分析研究了戊唑醇在缓释颗粒中的释放行为。通过菌丝生长速率法、盆栽试验和田间防效试验测定了Teb@HMS缓释颗粒对立枯丝核菌的抑制活性及对水稻纹枯病的防治效果。通过水稻种子发芽试验和斑马鱼试验对Teb@HMS的安全性进行了评价。结果表明:所制备的纳米二氧化硅载药粒子呈规整的中空介孔结构,对戊唑醇的载药率为52.02%,缓释时间长达400 h;Teb@HMS缓释颗粒降低了戊唑醇对非靶标生物水稻种子及斑马鱼的毒性,抑菌活性明显优于戊唑醇原药;盆栽和田间试验结果显示,施药后第18天Teb@HMS针对水稻纹枯病的保护作用防效分别达61.79%和70.42%。该研究可为中空介孔纳米二氧化硅缓释颗粒在农药减量化和植物病害绿色可持续防控方面提供技术支撑和理论指导。

关键词：中空介孔纳米二氧化硅戊唑醇缓释颗粒水稻纹枯病立枯丝核菌安全性评价生物活性

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation of Amide-Containing Insecticidal Derivatives from the Renewable Natural Productβ-Pinene

引用

Journal of Renewable Materials 2023年第5期11卷 2368-2380页

作者： Jiulong Wang yanqing gao Xiaoping Rao Zongde Wang Shibin Shang Zhanqian Song Hongyan Si Shengliang Liao East China Woody Fragrance and Flavor Engineering Research Center of National Forestry and Grassland Administration Camphor Engineering Research Center of National Forestry and Grassland AdministrationCollege of ForestryJiangxi Agricultural UniversityNanchang330045China College of Plant Protection Northwest Agriculture and Forestry UniversityYangling712100China College of Chemical Engineering Huaqiao UniversityXiamen361021China Institute of Chemical Industry of Forest Products China Academy of ForestryNational Engineering Laboratory for Biomass Chemical UtilizationState Forestry Administration’s Key and Open Laboratory for Forest Chemical EngineeringJiangsu Provincial Key Laboratory for Biomass Energy and MaterialNanjing210042China

The preparation of bioactive derivatives from the renewable natural product pinene is a hot research topic in the deep processing and utilization of *** this study,β-pinene was used to develop novel molecules as a promising new precursor of insecticide.A series of amide-containing derivatives ofβ-pinene were synthesized and *** insecticidal activities of these derivatives against Mythimna separate and Semiaphis heraclei were *** structure characterization results showed that the characterization data of amide-containing derivatives were in full agreement with their proposed *** insecticidal activities evaluation results indicated that amide-containing derivatives exhibited weak insecticidal activity against Mythimna separate,but exhibited moderate to good insecticidal activity against Semiaphis *** testing for 72 h,the corrected mortality against Semiaphis heraclei of compounds 5c,5e,5f,5 h,5j,and 5 m was 100%at 1000 mg/*** structure-activity relationship analysis results showed that the introduction of an amide group into the structure of derivatives improved their insecticidal activity against Semiaphis ***,the amide-containing derivatives containing the F and NO_(2) substituted benzene ring might improve their insecticidal activity against Semiaphis *** study will be helpful for the high value-added utilization of the natural renewable resourceβ-pinene and the development of novel insecticides.

关键词： Turpentine pinene derivative amide insecticidal activity

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：