检索结果-南通市图书馆

Research on conductive-material-filled electrodes for sidewall insulation performance in micro electrochemical machining

引用

Advances in Manufacturing 2023年第3期11卷 509-522页

作者： guo-dong Liu Yu-Lan Zhu Sheng-Gui Liu Chao-Jiang Li School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081People's Republic of China Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People's Republicof China

In micro electrochemical machining(ECM)processes,stray corrosion causes undesired metal dissolution and the deterioration of shape *** a sidewall-insulated electrode is an effective approach to suppressing stray *** sidewall-insulated electrodes are made of metal substrate and non-metallic thin ***,the thin-film insulating materials attached to a metal substrate are susceptible to damage in an electrolytic *** study presents a novel concept of the conductive-material-filled electrode for better sidewallinsulation *** micro-scale quartz tube serves as the insulating *** available conductive fillers including metal wire,molten metals,and silver powder are filled inside the working cathode of the quartz ***,the metal-wire-filled electrode,moltenmetal-filled electrode,and nano-powder-filled electrode are designed and *** the verification results of electrode toughness,material removal rate,and surface topography,the metal-wire-filled electrode and moltenmetal-filled electrode exhibit the same performance as a traditional metal-based electrode and much better *** contrast,the nano-powder-filled electrode is unable to withstand long-term ECM processes because of the loss of cured powder *** ECM experiments,microstructures with steep sidewalls(taper angle<9.7°)were machined using the metal-wire-filled electrode and molten-metal-filled electrode,which could replace the traditional electrode,achieving a longer service life and superior sidewall-insulation performance.

关键词： Electrochemical machining(ECM) Conductive-material-flled electrode Stray corrosion Sidewall insulation Quartz substrate

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

Effects of spinning parameters on microstructures of ellipsoidal heads during marginal-restraint mandrel-free spinning

引用

Advances in Manufacturing 2020年第4期8卷 457-472页

作者： Jia-Yang Chen Yong-Cheng Lin guo-dong Pang Xin-He Li School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083People's Republic of China State Key Laboratory of High Performance Complex Manufacturing Changsha 410083People's Republic of China

Marginal-restraint mandrel-free spinning is an advanced technology for manufacturing ellipsoidal heads with large diameter-thickness *** effects of spinning parameters on the forming accuracy of ellipsoidal heads have been studied,and optimized spinning parameters have been *** microstructure evolution of a workpiece is usually very complicated in the spinning *** this work,the influence of spinning parameters on the microstructures of two-pass spun ellipsoidal heads is *** is found that the forming angle and feed rate of the first pass,angle between passes,and feed rate of the second pass significantly affect the ***,the evolution rule of the microstructures near the inner and outer surfaces of the spun parts is almost consistent.A large forming angle,large angle between passes,or large feed rate of the second pass are beneficial to obtain uniform microstructures.A small or large feed rate of the first pass reduces the microstructure *** improve the microstructure uniformity between the inner and outer surfaces,the optimized spinning parameters are determined.

关键词： Spinning Thin-walled ellipsoidal heads Spinning parameters Microstructure evolution

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

Fluid Mud Measurement and Siltation Analysis in A Trial Excavated Channel in the Approach Channel of the Xiangshan Port

引用

China Ocean Engineering 2020年第3期34卷 421-431页

作者： DING Jian HU guo-dong WANG Zhen-xiang SHI Jian WU De-an Key Laboratory of Coastal Disasters and Defence Ministry of EducationHohai UniversityNanjing 210098China Yangtze River Estuary Investigation Bureau of Hydrology and Water Resource Shanghai 200136China

In order to clarify the distribution and variation of silt and fluid mud in the Waiganmen shallow section of the 50000-ton intake channel of the Xiangshan Port,and to understand the influence of the channel excavation on the surrounding flow conditions and the strength of the backsilting,especially the impact of typhoon on the sudden silting of the channel,so as to demonstrate the feasibility and stability of the channel *** fluid mud,hydraulic,sediment and topographic measurements were carried out in the study area,and the thickness of the fluid mud layers,tidal current,sediment and topographic data were ***-frequency sounder,gamma-ray densitometer and SILAS navigational fluid mud measurement system were used to monitor the fluid mud,and the results were compared and *** adaptability and accuracy of the three methods were *** SILAS navigational continuous density measurement system and gamma-ray fixed-point fluid mud measurement are used to detect the density,thickness and variation of the fluid mud *** on the hydrological observation data,the process of erosion and deposition in excavation channel and its influence mechanism are analyzed,and the distribution characteristics and evolution law of siltation in engineering area are given in the form of empirical *** research shows that the super typhoon can produce large siltation,which results in sudden siltation of the *** tidal current is the main dynamic factor of the change of erosion and siltation of the excavation *** the influence of reciprocating tidal current and excavation topography,the trial excavation trench is silted on the *** is fluid mud in the monitoring area of the trench,and the distribution of fluid mud is different in *** thickness of the fluid mud at the bottom of the trench is generally larger than that outside the trench and the slope of the trench,and the siltation of the trench tends to be *** re

关键词： excavation trench fluid mud backsilting measurement tidal current dynamic mechanism

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

Effect of the particle temperature on lift force of nanoparticle in a shear rarefied flow

引用

Chinese Physics B 2021年第7期30卷 324-331页

作者： Jun-Jie Su Jun Wang guo-dong Xia MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation Beijing Key Laboratory of Heat Transfer and Energy ConversionBeijing University of TechnologyBeijing 100124China

The nanoparticles suspended in a shear flow are subjected to a shear lift force,which is of great importance for the nanoparticle *** previous theoretical analysis on the shear lift,it is usually assumed that the particle temperature is equal to the temperature of the surrounding gas ***,in some particular applications,the particle temperature can significantly differ from the gas *** the present study,the effect of particle temperature on the shear lift of nanoparticles is investigated and the corresponding formulas of shear lift force are derived based on the gas kinetic *** extremely small nanoparticles(with radius R20 nm),the influence of the particle temperature can be *** the intermediate particle size,the relative error induced by the equal gas–particle temperature can be *** findings can bring an insight into accurate evaluation of the nanoparticle transport properties.

关键词： shear lift force nanoparticle temperature effect gas kinetic theory

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

Simulation and experiment analysis on thermal deformation of tool system in single-point diamond turning of aluminum alloy

引用

Journal of Central South University 2016年第9期23卷 2223-2229页

作者： ZHANG Yuan-jing dong guo-jun ZHOU Ming School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

The aim of this work is to simulate thermal deformation of tool system and investigate the influence of cutting parameters on it in single-point diamond turning(SPDT) of aluminum alloy. The experiments with various cutting parameters were conducted. Cutting temperature was measured by FLIR A315 infrared thermal imager. Tool wear was measured by scanning electron microscope(SEM). The numerical model of heat flux considering tool wear generated in cutting zone was established. Then two-step finite element method(FEM) simulations matching the experimental conditions were carried out to simulate the thermal deformation. In addition, the tests of deformation of tool system were performed to verify previous simulation results. And then the influence of cutting parameters on thermal deformation was investigated. The results show that the temperature and thermal deformation from simulations agree well with the results from experiments in the same conditions. The maximum thermal deformation of tool reaches to 7 μm. The average flank wear width and cutting speed are the dominant factors affecting thermal deformation, and the effective way to decrease the thermal deformation of tool is to control the tool wear and the cutting speed.

关键词： ultra-precision cutting tool wear diamond thermal deformation form accuracy

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

Interdecadal changes in the western Siberian summer mean and extreme rainfall during 1982-2021

引用

Atmospheric and Oceanic Science Letters 2024年第3期17卷 37-41页

作者： Yali Zhu Fangwu Song dong guo Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjingChina Carbon Neutrality Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

本文研究发现,西西伯利亚夏季降水在1995年后显著增加,2012年后又有所减少,极端降水日数和强度呈现一致的变化特征.伴随这两次降水的年代际增加/减少,西西伯利亚上空出现异常气旋/反气旋和水汽幅合/幅散.极端降水发生时的区域环流特征... 详细信息

本文研究发现,西西伯利亚夏季降水在1995年后显著增加,2012年后又有所减少,极端降水日数和强度呈现一致的变化特征.伴随这两次降水的年代际增加/减少,西西伯利亚上空出现异常气旋/反气旋和水汽幅合/幅散.极端降水发生时的区域环流特征在三个时段基本一致:西西伯利亚低空出现气旋性异常,高空为西北-东南向的异常气旋-反气旋偶极子型.1995-2011年期间,极端降水日数更多,强度更强,上述异常环流型也更强.

关键词：西伯利亚夏季降水年代际变化乌拉尔高压北大西洋波流相互作用

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

Anatomical Study on the Multi-Ovule Development and Abortion of Hanfu Apple

引用

Journal of Integrative Agriculture 2014年第4期13卷 770-777页

作者： YANG Xu-yuan MA Huai-yu LIU guo-cheng Lü De-guo QIN Si-jun DU guo-dong College of Horticulture Shenyang Agricultural University/Key Laboratory for Northern Fruit Trees Cultivation and Physio-Ecology of Shenyang City

The terminal flower buds of 6-yr-old Hanfu apple were used to study the ovule development, ovular characteristics, cell death of abortive ovules, and dynamic change of starch grain quantity in the embryo sac with paraffin slices and terminal deoxynucleotidyl transferase-mediated fluorescein deoxyuridine triphosphate nick-end labeling （TUNEL） system. Four anatropous ovules in each ventricle could be observed before flowering. With the developing of floral organ, the bulk of normal ovules enlarged in each ventricle, the mature embryo sac differentiated into nucellus, and the egg cell developed into zygote by double fertilization. A large number of starch grains were observed during pollen tube growth and double fertilization, which guaranteed basic nutrient supply in the normal development of ovules. Moreover, abortion phenomenon of runtish ovules emerged at the stages of mature embryo sac, double fertilization and zygote development. The abortion characteristics included deformity of ovule development, degradation of nucellus tissue, separation between funiculus and ovule, abnormality of four-nucleate embryo sac, as well as development interruption of mature embryo sac. TUNEL analysis proved that ovule abortion was programmed cell death.

关键词： Hanfu apple multi-ovule abortion programmed cell death starch grain

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

Expression and antioxidation of Nrf2/ARE pathway in traumatic brain injury

引用

Asian Pacific Journal of Tropical Medicine 2013年第4期6卷 305-310页

作者： Zhen-guo Cheng guo-dong Zhang Peng-Qiang Shi Bao-Shun Du Second Department of Neurosurgery Xinxiang Central Hospital

Objective:To explore the expression of Nrf2/ARE pathway in hindbrain tissue after the traumatic brain injury（TBI） and its anli-oxidative stress effect in the secondary nerve ***: The mice with Nrf2 gene knockout were used for the establishment of brain injury *** experimental animals were divided into four groups:(Nrf2+/+) sham-operation group,(Nrf2+/+) brain injury group,（Nrf2T） sham-operation group and(Nrf2-/-) brain injury *** specimen 24 h after cerebral trauma was *** RT-PCR method was adopted to detect the expression of Nrf2 mRNA in brain;Western blotting method was adopted to detect the levels of Nrf2,HO-1 and NQO1 proteins in brain;EUSA method was adopted to detect the oxidative stress indicators: protein carbonyls,4-hydroxy-2-nonenal（4-HNE） and 8-hydroxy-2’-deoxyguanosine（8-OHdG）. ResuHs:The Nrf2 mRNA and protein of Nrf2-/- mice were not expressed,and the diflerence of the relative amount of Nrf2 mRNA between Nrf2+/+ TBI group and Nrf2+/+ sham-operation group was not statistically significant（P>0.05）;the level of Nrf2 protein in Nrf2+/+ TBI group increased significantly compared with the Nrf2+/+ sham-operation group（P-/- mice decreased obviously compared with the Nrf2+/+ mice（P+/+ mice increased obviously compared with the corresponding sham-operation group（P-/- mice in TBI group had no obvious change compared with the corresponding sham-operation group（P>0.05）;there was only a little amount of expression of protein carbonyls,4-HNE and 8-OHdG proteins in brain tissues in the Nrf2-/+ and Nrf2-/- shamoperation groups,and the difference was not statistically signif

关键词： Traumatic brain injury Nrf2/ARE pathway Gene expression Anti-oxidative stress

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

Research on Rolling Load Distribution Method based on Data Mining

引用

Journal of Iron and Steel Research International 2005年第6期12卷 30-32,53页

作者： ZHANG Yan-hua LIU Xiang-hua WANG guo-dong Northeastern University Shenyang 110004 China Shenyang Institute of Chemical Technology Shenyang 110142 China

A new method of establishing rolling load distribution model was developed by online intelligent information-processing technology for plate rolling. The model combines knowledge model and mathematical model with using knowledge discovery in database （KDD） and data mining （DM） as the start. The online maintenance and optimization of the load model are realized. The effectiveness of this new method was testified by offline simulation and online application.

关键词： rolling load distribution information processing knowledge discovery data mining

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

Gastric metastasis presenting as submucosa tumors from renal cell carcinoma:A case report

引用

World Journal of Clinical Cases 2022年第27期10卷 9805-9813页

作者： Wen-guo Chen guo-dong Shan Hua-Tuo Zhu Li-Hua Chen guo-Qiang Xu Department of Gastroenterology The First Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Gastric metastasis from renal cell carcinoma(RCC) is an extremely rare clinical *** to an easily neglected RCC history,nonspecific symptoms and underrecognized endoscopic presentation may lead to a potential diagnostic pitfall in daily clinical *** SUMMARY We present a case of metastatic gastric tumors arising from RCC 5 years after radical ***,multifocal metastases to the gallbladder,pancreas and soft tissue were *** year previously,a solitary submucosal discoid tumor with a central depression was detected in the gastric fundus in a 65-year-old *** ultrasonography(EUS) showed a 1.12 x 0.38 cm lesion originating from the deeper mucosal layers with partially discontinuous *** year later,the endoscopic findings of the lesion showed various changes.A large lesion of the protruding type(2.5 cm × 2 cm) was found in the fundus at the same *** showed a heterogeneous mass that involved the mucosa and submucosal *** addition,two small similar submucosal lesions 0.4-0.6 cm in size were *** lesions had a central depression,surface mucosal congestion and thickened *** two adjacent lesions in the fundus were resected by endoscopic submucosal *** on the postoperative pathological analysis,the patient was diagnosed with gastric metastasis from *** Gastric metastasis from RCC should be considered in patients with a history of RCC irrespective of the time interval involved.

关键词： Gastric metastasis Renal cell carcinoma Nephrectomy Endoscopic ultrasonography Endoscopic submucosal dissection Case report

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：