检索结果-南通市图书馆

SYNTHESIS AND CHARACTERIZATION OF AMINO FUNCTIONALIZED LADDER-LIKE POLYSILSESQUIOXANES AND THEIR HYBRID FILMS WITH POLYIMIDE

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer science 2013年第3期31卷 427-433页

作者： Qiu-shuang gao guo-feng Tian Sheng-li Qi Zhan-peng wu 武德珍 State Key Laboratory of Chemical Resource engineering Beijing University of Chemical Technology

Ladder-like polysilsesquioxanes （LPSQs） with different amino contents have been synthesized by controlling of the dosage of Pd/C catalyst. The concentration and activity of amino groups were investigated by Fourier transform infrared spectroscopy. Polyimide （PI）/LPSQ hybrid films have been prepared by incorporating of the obtained LPSQs with different amino contents into PI matrix, respectively. The interfacial interactions between PI matrix and LPSQ were studied with scanning electron microscopy and X-ray photoelectron spectroscopy, meanwhile the thermal and mechanical properties of the hybrid films were studied using dynamic mechanical analysis and tensile tests. The results indicate that the functionality of LPSQ has great effects on the interfacial interactions and the properties of hybrid films. With the increase of amino content, both the interracial interactions and the cross-linking density of hybrids enhanced, which results in the decline of surface silicon concentration, increase of Young＇s modulus and drop of elongation at break. Excessive amino content makes the hybrid films brittle and leads to incomplete imidization.

关键词： Organic-inorganic Hybrid Amino functionalized ladder-like polysilsesquioxane Polyimide.

Using the traditional model to evaluate the active force of the human lateral rectus muscle

在线全文

学校读者我要写书评

暂无评论

science china(Physics,Mechanics & Astronomy) 2014年第5期57卷 983-987页

作者： gao ZhiPeng CHEN WeiYi JING Lin FENG PengFei wu XiaoGang guo HongMei Institute of Applied Mechanics and Biomedical engineering Taiyuan University of Technology Impact Mechanics Laboratory Department of Mechanical EngineeringNational University of Singapore

The information on the force of extraocular muscles(EOMs)is beneficial for strabismus diagnosis and surgical planning,and a direct and simple method is important for surgeons to obtain these *** on the traditional model,a numerical simulation method was proposed to achieve this aim,and then the active force of the lateral rectus(LR)muscle was successfully simulated when the eye rotated every angle from 0°to 30°in the horizontal plane from the nasal to the temporal *** order to verify these simulations,the results were compared with the previous experimental *** comparison shows that the simulation results diverged much more than the experimental data in the range of 0°–10°.The errors were corrected to make the simulation results closer to the experimental ***,a general empirical equation was proposed to evaluate the active force of the LR muscle by fitting these data,which represent the relationship between the simulation forces and the contractive amounts of the LR muscle.

关键词： force extraocular muscles lateral rectus muscle eye movement model

南昌地铁地下多管线近邻地铁人行通道的施工影响分区

在线全文

学校读者我要写书评

暂无评论

科学技术与工程 2024年第11期24卷 4679-4688页

作者：吴波郑卫强郭方雨徐世祥万友生覃君朱文华东华理工大学土木与建筑工程学院南昌330013 广西大学土木建筑工程学院南宁530004 南昌轨道交通集团有限公司地铁项目管理分公司南昌330038 中铁二局第六工程有限公司成都610083

针对地下地铁人行通道暗挖施工对近邻多管线扰动影响问题,依托南昌地铁3号线邓埠站1号出入口人行通道暗挖工程,采用数值计算与理论分析相结合的方法,系统研究了通道暗挖施工扰动作用下近邻多管线的力学特性,总结关键因素对管线力学行为... 详细信息

针对地下地铁人行通道暗挖施工对近邻多管线扰动影响问题,依托南昌地铁3号线邓埠站1号出入口人行通道暗挖工程,采用数值计算与理论分析相结合的方法,系统研究了通道暗挖施工扰动作用下近邻多管线的力学特性,总结关键因素对管线力学行为的影响规律,提出了通道暗挖下近邻密集管线影响分区计算方法与控制措施。结果表明:结合Peck曲线分布规律确定出以控制值的60%与20%作为强影响分区、弱影响分区、无影响分区的阈值;采用多元非线性函数进行拟合得出的线竖向位移与多因素的关系函数,对影响分区划分效果较好;建立的地铁隧道暗挖对近邻密集管线强弱影响分区方法,可通过有效的措施将密集管线强影响区转变为弱影响区和无影响区,进而保障施工安全。

关键词：通道暗挖多管线数值模拟影响区控制措施

江苏省直播稻种植主要问题与对策——基于“农技耘”APP问答数据的调查研究

在线全文

学校读者我要写书评

暂无评论

中国稻米 2024年第3期30卷 78-83页

作者：张耀元胡星晨孙冬杨谦吴慧扬郭威徐强高辉窦志农业农村部长江流域稻作技术创新中心/江苏省粮食作物现代产业技术协同创新中心/扬州大学水稻产业工程技术研究院/江苏省作物栽培生理重点实验室江苏扬州225009

随着经济的快速发展,农村优质劳动力逐渐往城市迁移。直播稻作为一种轻简化种植方式,近年来种植规模迅速扩增。“农技耘”是江苏农业科技服务大数据平台,集“农技推广专业知识库、专家问诊、视频诊断、信息采集发布”为一体。本研究以... 详细信息

随着经济的快速发展,农村优质劳动力逐渐往城市迁移。直播稻作为一种轻简化种植方式,近年来种植规模迅速扩增。“农技耘”是江苏农业科技服务大数据平台,集“农技推广专业知识库、专家问诊、视频诊断、信息采集发布”为一体。本研究以“农技耘”水稻专家王才林和李刚华6年间3 557条问答为调查样本,整理出涉及直播稻的问题308条,并进一步划分为杂草防治、直播稻品种选择和性状咨询、水肥等综合管理、长势诊断与决策、水稻播种环节、种植地块选择等六大类问题。针对其中的具体问题提出了相关对策。

关键词：直播稻江苏省 “农技耘”APP

维普期刊数据库博看期刊

Stability of NiCrAlY coating/titanium alloy system under pure thermal exposure

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2017年第8期36卷 659-665页

作者： Xiao-Min Peng An-Ru wu Li-Jun Dong You-Rui Tao Wei-guo gao Xiang-Lin Zhou State Key Laboratory of Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China school of mechanical engineering Hunan Institute of EngineeringXiangtan 411101China

In this paper,NiCrAlY coating was deposited on TC4 titanium alloy using arc ion plating,and the stability of NiCrAlY coating/TC4 substrate system under pure thermal exposure was analyzed in a wide temperature *** the thermal exposure,β→γ′→γphase transformation takes place in the NiCrAlY *** NiCrAlY coating phases totally decompose above the allotropic transformation temperature of *** allotropic transformation ofα-Ti to β-Ti of the substrate significantly influences the stability of NiCrAlY coating/TC4 substrate *** coating elements are mainly consumed by interfacial reactions below the allotropic transformation temperature of *** the allotropic transformation temperature of TC4,NiCrAlY coating elements are mainly consumed by element dissolution in β-*** NiCrAlY coating totally degrades for the dissolution of coating elements in the substrate to form thickβ-Ti stabilized layer.

关键词： NiCrAlY coating Titanium alloy Stability Pure thermal exposure Degradation

人工缺陷下感应淬火重载铁路车轴损伤容限评价

在线全文

学校读者我要写书评

暂无评论

表面技术 2024年第19期53卷 173-185页

作者：吴鹏程高杰维赵海于文坛徐磊郭新凯林鹏飞陈宏韩靖西南交通大学材料科学与工程学院成都610031 西华大学机械工程学院成都610039 电子科技大学广东电子信息工程研究院广东东莞523808 马鞍山钢铁股份有限公司河北马鞍山243000 西华大学材料学院成都610039 中车青岛四方机车车辆股份有限公司山东青岛266111

目的研究不同感应淬火工艺对重载铁路车轴钢试样梯度结构的影响,阐明不同人工缺陷下感应淬火试样的疲劳断裂行为,并评价损伤容限,为重载铁路车轴感应淬火工艺设计和损伤容限评价提供理论基础和评价方法。方法在AAR-CM车轴钢试样表面采... 详细信息

目的研究不同感应淬火工艺对重载铁路车轴钢试样梯度结构的影响,阐明不同人工缺陷下感应淬火试样的疲劳断裂行为,并评价损伤容限,为重载铁路车轴感应淬火工艺设计和损伤容限评价提供理论基础和评价方法。方法在AAR-CM车轴钢试样表面采用不同感应淬火工艺参数制备不同深度淬硬层,采用X射线测量淬硬层残余应力分布,通过电火花和空气炮在正火态和感应淬火试样表面制备不同尺寸的电火花或冲击损伤,采用疲劳试验机研究损伤试样的弯曲疲劳性能,借助光学显微镜和扫描电镜分析试样的损伤机理和疲劳断裂行为,并对其疲劳性能进行评价。结果在3种工艺下感应淬火试样有效淬硬层深度分别为800、1200、1400μm。在电火花缺口尺寸较小时,感应淬火试样的疲劳强度比正火态试样高出50%。在冲击损伤尺寸较小时,感应淬火试样的疲劳强度比正火态试样高出40%。较小的尺寸冲击损伤对正火态和感应淬火处理试样的疲劳强度无影响。结论感应淬火可提高重载铁路车轴钢试样表面强度,进而提高其耐冲击性能,残余压应力减弱了电火花缺口试样和低速冲击损伤对试样疲劳强度的影响,高速冲击破坏了试样表面完整性,并削弱了残余压应力的作用,试样的疲劳强度急剧降低。文中设计的淬硬层深度对感应淬火试样损伤容限的影响较小。

关键词：铁路车轴感应淬火淬硬层深度人工缺陷损伤容限

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

崩塌落石作用下埋地管道力学响应分析

非常规油气 2024年第2期11卷 118-125页

作者：梁平周泽山吴晓霞高春元夏志伟邱旭颜黎张华忠重庆科技大学石油与天然气工程学院重庆401331 重庆科技大学安全工程学院(应急管理学院) 重庆401331

坍塌落石是导致埋地油气管道毁坏的重要地质灾害之一。在落石冲击时管道内部会产生应力和应变,可能导致管道变形、损坏和泄漏,对人们的生命财产造成严重威胁。通过ABAQUS软件建立落石-土体-管道耦合作用的有限元模型,对落石冲击埋地油... 详细信息

坍塌落石是导致埋地油气管道毁坏的重要地质灾害之一。在落石冲击时管道内部会产生应力和应变,可能导致管道变形、损坏和泄漏,对人们的生命财产造成严重威胁。通过ABAQUS软件建立落石-土体-管道耦合作用的有限元模型,对落石冲击埋地油气管道的力学响应问题进行分析,研究管道内压、落石偏心距和落石冲击速度等工程因素对管道应力应变的影响规律。结果表明:1)在冲击过程中,管顶受到土体应力向管道两侧壁面挤压,最大塑性应变出现在管道凹陷边缘,呈椭圆状;2)随着落石冲击速度的减小和偏心距的增加,管道应力变化和变形程度均逐渐减小;随着内压的增大,管道等效应力逐渐增大,而管道应变逐渐减小。分析结果揭示了落石冲击管道的物理本质和特征,为管道敷设和工程检测提供理论依据。

关键词：坍塌落石油气管道应力应变数值模拟

Deformation treatment and microstructure of graphene-reinforced metal matrix nanocomposites: A review of graphene post-dispersion

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 888-899页

作者： Yong Mei Pu-zhen Shao Ming Sun guo-qin Chen Murid Hussain Feng-lei Huang Qiang Zhang Xiao-sa gao Yin-yin Pei Su-juan Zhong gao-hui wu State Key Laboratory of Explosion science and technology Beijing Institute of TechnologyBeijing 100081China Institute of Defense engineering AMSPLABeijing 100036China school of Materials science and engineering Harbin Institute of TechnologyHarbin 150001China Department of Chemical engineering COMSATS University IslamabadLahore CampusLahore 54000Pakistan State Key Laboratory of Advanced Brazing Filler Materials&technology Zhengzhou Research Institute of Mechanical Engineering Co.Ltd.Zhengzhou 450001China

Graphene/aluminum(Gr/Al)composites have attracted the attention of researchers all over the world due to their excellent ***,graphene agglomerates easily because of the van der Waals force between graphite sheets,thereby affecting the performance of the *** the agglomeration of graphene and dispersing it uniformly in the Al matrix is a key *** the preparation process,predispersion treatment and deformation treatment can play important roles in graphene *** have conducted a series of research and literature reviews of the graphene predispersion and consolidation of ***,they paid less attention to post-deformation *** review summarizes different deformation treatments involved in the preparation process of Gr/Al composites and the evolution of the microstructure during the *** on deformation parameters is expected to further improve the properties of Gr/Al composites and would provide a deep understanding of the strengthening effect of graphene.

关键词： graphene/aluminum composites deformation treatment dispersion microstructure

Pressure control method and device innovative design for deep oil in-situ exploration and coring

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 1169-1182页

作者： Nian-Han wu Ming-Zhong gao Liang-Yu Zhu Jia-Nan Li Dong Fan Bin You Wei Luo guo-Dong Zhu school of mechanical engineering Sichuan UniversityChengdu610065China State Key Laboratory of Hydraulics and Mountain River engineering College of Water Resource and HydropowerSichuan UniversityChengduSichuan 610065China guangdong Provincial Key Laboratory of Deep Earth sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhenGuangdong 518061China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuan 610500China Xi'an Research Institute China Coal Technology&Engineering Group CorpXi'anShaanxi 710077China Haiwang mechanical Electronic engineering technology Co. LTDWuhanHubei 430064China Zaoshenzhuang Village Hancheng TowuLubei DistrictTangshanHebei 064002China

Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cores and cannot guide the development of deep oil and gas resources on Earth. The fundamental reason is the lack of temperature and pressure control in in-situ coring environments. In this paper, a pressure control method of a coring device is studied. The theory and method of deep intelligent temperature-pressure coupling control are innovatively proposed, and a multifield coupling dynamic sealing model is established. The optimal cardinality three term PID (Proportional-Integral-Differential) intelligent control algorithm of pressure system is developed. The temperature-pressure characteristic of the gas-liquid two-phase cavity is analyzed, and the pressure intelligent control is carried out based on three term PID control algorithms. An in-situ condition-preserved coring (ICP-Coring) device is developed, and an intelligent control system for the temperature and pressure of the coring device is designed and verified by experiments. The results show that the temperature-pressure coupling control system can effectively realize stable sealing under temperature-pressure fields of 140 MPa and 150 °C. The temperature-pressure coupling control method can accurately realize a constant pressure inside the coring device. The maximum working pressure is 140 MPa, and the effective pressure compensation range is 20 MPa. The numerical simulation experiment of pressure system control algorithm is carried out, and the optimal cardinality and three term coefficients are obtained. The pressure steady-state error is less than 0.01%. The method of temperature-pressure coupling control has guiding significance for coring device research, and is also the basis for temperature-pressure decoupling control in ICP-Coring.

关键词： Deep oil exploration Fidelity coring device Temperature-pressure coupling control theory Pressure control algorithm Temperature-pressure field alternating model