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1.
This paper presents the results of a test program for flexure reinforcing characteristics of gless fiber-rein forced polymer(GFRP) sheets bonded to masonry beams. A total of eight specimens subjected to monotonic four-point bending were tested up to failure. These specimens were constructed with two different bond patterns. Six of these specimens were reinforced by using GFRP sheets prior to testing, and the remaining two were not reinforced. The test results indicate a significant increase in both load-bearing capacity and ductile performance of the reinforced walls over the unreinforced ones.  相似文献   

2.
InfluenceofPredeformationonShapeMemoryEffectinaFe-Mn-Si-NiPolycrstallineAlloyWANGYongqian;LAIZhonghong;YANGJianhua;ZHAOLianch...  相似文献   

3.
A discretization precision control method based on the second-order osculating surface is proposed. The discretization precision of 3-D solid is controlled according to the error between the discrete solid surface and its second-order osculating surface. The global maximal error has been gotten after analyzing all the extremums of the error function. It can be used in controlling and optimizing the discretization precision of 3-D solid in computer 3-D modeling and NC milling path generation.  相似文献   

4.
FurtherInvestigationforNonlinearFreeVibrationofElasticCircularPlatewithLargeAmplitudeGAIBingzheng;CUIGuangyu(盖秉政,崔光育)(Dept.of...  相似文献   

5.
In order to safely exploit coal resource, protection coal pillars must be prepared in coal mines. Some correlative parameters of protection coal pillar are calculated by Drop face and Drop line methods. Models of protecting surface objects and coal pillars are established by TIN modeling and object-oriented technique. By using ACCESS2000as the database and the VC++ and OpenGL as the language, the calculation of protective coal pillars is realized and the 3D-visulizaiton system for protected objects on ground surface and for coal pillars is developed. The system can obtain the data of characteristic points on the surface interactively from the digitized mine topography map, constructing 3D model automatically. It can also obtain the interrelated parameters of the coal seam and drill hole data from existing geolog!cal surveying database to calculate the location, surface area and the total coal columns. The whole process can be computed quickly and accurately. And the 3D visualization system was applied in a mine, showing that the system solve the problem of complex calculation, not only realized the automatic 3D mapping and visualization of coal pillars for buildings protection, but also greatly improves the working efficiency.  相似文献   

6.
ExperimentalInvestigationoftheDeformationofHelicalGearswithDouble-Circular-ArcToothProfileUsingLinearVariableDifferentialTran...  相似文献   

7.
ManufactureofEnd-micro-manipulatorwithTwoDegreesofFreedomanditsDrivingSystemforRobot¥(刘劲松)(蔡鹤皋)LIUJinsong;CAIHegao(RobotReset...  相似文献   

8.
0 INTRODUCTIONTheacidogenicphasereactoroftwo phaseanaerobictreatmentsystemhasremarkableadvantagesfortreatingsulfate ladenorganicwastewater[1] ,anditisacontrolledmicrobialecosystem[2 ] .Therestrictiveecologicalfactorsin cludingCOD/SO4 2 - ratio ,sulfateloadingrat…  相似文献   

9.
The surface properties of kaolinite were determined using density functional theory discrete variational method (DFT-DVM) and Gaussian 03 program. A SiO4 tetrahedral hexagonal ring with two A1 octahedra was chosen to model the kaolinite crystal. The total density of states of the kaolinite cluster are located near the Fermi level at both sides of the Fermi level. Both the highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO) of kaolinite indicate that kaolinite system can not only readily interact with electron-acceptor species, but also readily interact with electron-donor species on the edge surface and the gibbsite layer surface, and thus, shows amphoteric behavior. Substitution of Al3^+ for Si4+ in the tetrahedral site linking the vacant Al3^+ octahedra does not increase the surface chemical reactivity of kaolinite, while substitution of Al3^+ for Si^4+ in the tetrahedral site with the apex O linking Al3^+ octahedra increase the surface chemical reactivity of the siloxane surface of kaolinite, especially acting as electron donors. Additionally, substitution of Al3^+. for Si^4+ in the tetrahedral site results in the re-balance of charges, leading to the increase of negative charge of the coordinated O atoms of the AlO4 tetrahedra, and therefore favoring the formation of ionic bonds between cations and the surface O atoms in the basal plane.  相似文献   

10.
Experiment of synthesizing a disperser for coal water slurry (CWS) by using fractions of anthracene oil from high-temperature coal tar was performed. The orthogonal test was used to investigate the influence of temperature, time, quantity of sulfonation agent and condensation agent and the interaction of these factors on properties of the disperser. The result shows that the influence of temperature, time, quantity of sulfonation agent and condensation agent, and the interaction of sulfonation time and sulfonation agent has a significant influence on the properties of disperser. The optimal condition of synthesis is that in 150g of the fractions of anthracene oil, 40 mL of sulfonation agent is added and sulfonated for 3 h at 130℃, then, 10 mL of condensing agent is added and condensated for 1.5 h at 115℃  相似文献   

11.
对精密、超精密加工时PCD刀具后刀面的熨压作用进行了分析,建立了后刀面错位熨压的理论模型,并通过实验研究了后刀面的错位熨压作用,对提高加工表面质量有指导意义。  相似文献   

12.
通过切削实验,研究PCD刀具铣削SiC颗粒尺寸较大、体积比含量较高的SiCp/Al复合材料时,切削速度、每齿进给量、切削深度对已加工表面粗糙度的影响,根据对实验结果分析得出切削用量对已加工表面粗糙度的影响规律.  相似文献   

13.
单点金刚石车削表面粗糙度的研究   总被引:1,自引:0,他引:1  
为了进一步研究单点金刚石车削加工所获得的工件表面粗糙度,在前人工作的基础上,详细阐述了现有的具有代表性的单点金刚石车削表面粗糙度的研究方法及其优缺点,主要包括基于切削理论的方法、谱分析方法和人工智能方法.研究表明,最有前途的方法是将上述几种方法结合起来,以发挥各自的优点.  相似文献   

14.
在高速切削过程中,切削速度、进给速度是影响加工表面粗糙度的决定性因素.用PCD刀具对铝合金孔进行高速切削时,对不同切削参数下的表面粗糙度变化规律进行了理论分析和试验研究.通过试验确定的合理参数值可提高产品的加工质量.  相似文献   

15.
用板状试样研究了形成光滑铸件表面的一般规律,提出了合理的涂料层结构及浇注、冷却条件,通过几种典型铸件试制,表明铸件表面粗糙度容易达到0.8~1.6μm,得到了满意的结果。  相似文献   

16.
借助于切屑形成过程的动态观察研究,分析了金钢石刀具切削非晶态聚合物时的切屑形成形式和相应的切削力比值变化规律。在此基础上提出了相应的已加工表面形成模型,并用SMM(ScanningMechanicalMicroscope)对已加工表面形貌进行了微观观察和表面平面特征分析,拟阐明金钢石刀具切削非晶态聚合物的已加工表面形成机理。  相似文献   

17.
引入一种新型的在线电解连续修整砂轮磨削方法-ELID磨削,对钢结硬质合金进行精密镜面磨削,得到了Rz=0.091μm的良好镜面表面,一次磨削成形,效率高,可取代目前的多级研磨工艺。  相似文献   

18.
对表面粗糙度检查记录仪进行虚拟仪器化改造,确定模块化的改造方案.设计调试测量电路;选择USB采集卡实现A/D转换和计算机接口,并实现计算机监控零位与测量控制;根据表面粗糙度最新国家标准中各参数的定义和各项预实现功能,利用VB6.0软件平台构建测量软件;对整体测量系统进行调试和测量误差测试,表明改造后的表面粗糙度检测仪可方便地进行各项指标的检测.  相似文献   

19.
针对复杂型面电解加工流场设计难的问题,根据磁场和电场相互作用的原理,在电解加工装置中安置磁路,使磁场作用于作为导电介质和反应介质电解加工间隙中的流体,影响间隙中离子的分布,进而影响流场,以简化流场设计.为了提高电解加工间隙的实际磁感应强度,在夹具和阴极中的磁铁两头安置轭铁;同时分别采用磁感应强度不同的铁氧体和钕铁硼,以修正零件两头与中部流场的差异.试验表明磁场配置对减轻型面的杂散腐蚀有一定影响.  相似文献   

20.
聚晶金刚石热稳定性的研究   总被引:5,自引:0,他引:5  
通过对3种聚晶金刚石在空气中差热和热重曲线的分析,了解了其在空气中的氧化方式.通过扫描电镜对高频感应加热的复合片进行了形貌观察,以了解其热损伤的程度.结合聚晶金刚石的差热曲线和SEM照片,确定以差热曲线的起始氧化温度作为其热稳定性的表征温度.结果表明:对应于复合片SYNDITE CTB002、CTB010、CTB025,热稳定性表征温度分别为650、690、720℃.  相似文献   

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