首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   26篇
  免费   3篇
  国内免费   4篇
电工技术   1篇
综合类   1篇
金属工艺   3篇
机械仪表   5篇
建筑科学   1篇
轻工业   7篇
无线电   2篇
一般工业技术   6篇
冶金工业   1篇
原子能技术   2篇
自动化技术   4篇
  2023年   1篇
  2017年   1篇
  2016年   3篇
  2014年   1篇
  2013年   5篇
  2012年   1篇
  2010年   3篇
  2009年   4篇
  2008年   2篇
  2007年   1篇
  2006年   1篇
  2004年   2篇
  1998年   1篇
  1997年   1篇
  1994年   1篇
  1993年   1篇
  1989年   1篇
  1979年   1篇
  1978年   2篇
排序方式: 共有33条查询结果,搜索用时 62 毫秒
1.
Heat-induced Gelation of Chicken Gizzard Myosin   总被引:2,自引:0,他引:2  
Chicken gizzard myosin solution formed a gel when heated above 40°C. The rigidity of the gel was constant above 65°C. Maximum pH for gel formation was 5.9 at 0.6M and 5.7 at 0.15M KCl. Higher rigidity of the myosin gel was observed at low ionic strength than at high ionic strength. Rigidities of myosin at 0.6M KCl increased by (mg/mL)2.5 and at 0.15M (mg/mL)1, 4 myosin concentration. The strength of gizzard myosin gels was comparable to that of myosin gels from chicken breast muscle under similar conditions.  相似文献   
2.
目的 解决ADC12铝合金汽车发动机支架在挤压铸造成形工艺下的缺陷问题。方法 利用ProCAST模拟软件对该汽车发动机支架的挤压铸造充型和凝固过程进行模拟,对挤压铸造工艺参数进行正交试验设计并模拟得到最佳工艺参数,对铸件浇注远端厚壁部位采取局部加压优化措施,并对厚壁部位进行X-Ray探伤,观察铸件的缺陷情况。结果 对挤压铸造的工艺参数进行正交试验极差分析后,发现各工艺参数按对铸件凝固后质量的影响程度从大到小的顺序依次为挤压比压、浇注温度、模具温度。通过正交试验得到优化后的工艺参数为浇注温度730 ℃、模具温度300 ℃、挤压比压150 MPa。局部加压时挤压销的最佳激活时间为4 s,此时可以完全消除铸件内部的缩孔缩松缺陷。选择优化后的工艺参数生产该汽车发动机支架,产品外观完整,没有出现表面裂纹等缺陷。在X-Ray探伤下无明显缺陷,内部质量良好。结论 选择合理的浇注温度、模具温度和挤压比压可以有效减少铸件内部的缩孔缩松缺陷,采用局部加压并合理控制挤压销的激活时间可以完全消除缩孔缩松缺陷。  相似文献   
3.
由于对环境的关注和废料的处理问题,近些年对工业废料进行了积极的回收.回收废料作为混合材被广泛应用在GRC混凝土中.本文对使用了工业废料混合材的GRC的基本物理性能和耐久性所进行了研究.我们的结论是:粉煤灰、矿渣和硅灰的使用可以提高GRC的耐久性.在这些结论的基础上,提出将耐久性好的GRC配合比与回收废料结合在一起.经加速老化试样的抗折强度相当于暴露在日本室外10年时间的试件的强度,高于最初的强度,等于传统GRC的强度.由于火山灰反应消耗了基体中的Ca(OH)2,分别通过热分析和X射线衍射分析,在加速老化的含有矿渣和硅灰的砂浆中没有发现Ca(OH)2.  相似文献   
4.
The effects of modes of heat transfer (radiation or convection) on the baking color development of food were studied. An experimental baking oven that could be altered to two heat transfer modes was designed; the ratio of heat by radiative transfer to total heat transferred was about 30% or 70%. The glucose-glutamate solutions were heated at different air temperatures to measure the browning rates to calculate the activation energies. Cookies were baked at 200°C to measure the lightness of color on the surface and the surface temperature. It was clarified that the development of color depended on the temperature only.  相似文献   
5.
基于微细加工工艺,设计并制备了一种指向性良好的压电复合材料的超声波探测器。该探测器由压电振子、阻尼器、中继板和特高频(UHF)连接器构成。压电振子由4×4个(80μm×80μm×130μm)(长×宽×高)的锆钛酸铅(PZT)压电柱状阵列及阵列缝隙填充环氧树脂而构成。当压电振子施加高频交流电压时,柱状PZT阵列产生纵向伸缩运动,从而产生超声波并向介质辐射。作为填充材料的环氧树脂,能够吸收掉因柱状PZT阵列其他方向振动而引起的噪声,使探测器在纵向上能产生指向性良好的超声波,从而提高了该探测器的灵敏度。测试结果表明,该微压电探测器指向性好,灵敏度高,精度高和抗干扰性好,可应用在泥沙的含水量测量中。  相似文献   
6.
Abstract

A novel method called Visual Q-Analysis (VQA) is proposed to analyze structures of complex systems, where the structure of a system is represented by simplicial complex in topology and analyzed in terms of q-connectivity. Two different types of hierarchies, Q-hierarchy and F-hierarchy, are introduced and algorithms are given. In order to draw these hierarchies in a visually understandable form, SKETCH system is used. By inspecting the combination of the drawings and measures such as Q-vector, eccentricity and concentricity we can grasp readily the structural information embedded in the complex. This method is applied to a structural study of technological development of future computers of Japan in terms of relationships between social needs and technological requirements (seeds). Results of the application not only show the effectiveness of VQA to support in planning technological developments but also suggest wide applicabilities of VQA to various other fields.  相似文献   
7.
高分子材料,如甲基丙烯酸甲酯(polymethyl methacrylate,PMMA),由于其价格相对低廉和容易加工,在集成电路和MEMS研究中受到广泛的关注.本文提出了一种基于PMMA基板的多层同步辐射光刻技术,用于制作微驱动器等有移动部件的设备.设计的多层结构包括140个单元的叉指平行电容器,每个电容器的间隔是2μm,最小尺寸是4μm,厚度是200μm,故深宽比达到50:1.该制造方法具有高深宽比、高产出率及成本低等优点.  相似文献   
8.
Abstract

Visual Q-Analysis (I) proposed in Part I are extended to evaluate strategies of technological developments. The method for extension is based on F-Hieraichies generated by Visual Q-Analysis (I), which is a method for structural analysis. Utility indicators of technologies are first computed by taking account of their relevancy to social needs, and then preferred paths of technological developments are determined by utilizing the indicators. Algorithms to obtain the indicators and the paths are presented and their properties are studied. The method is applied to analyze strategies for developing future computers in Japan.  相似文献   
9.
描述了一种新的亚波长光栅的微细加工技术,即X光光刻得到相应的亚微米级的线宽图形,再利用显影技术获得了高深宽比的立体亚波长光栅.用此纳米加工技术获得了栅距为500nm、250nm、150nm,光栅高度为1900nm的特殊纳米光栅模具,开发了纳米无反射结构,并研制成功了亚波长光栅.该亚微米线宽微细加工技术可用于布拉格光栅、DVD读写头、无反射表面等需要亚微米结构的器件中.  相似文献   
10.
The roles of the rotations in the process of chirality appearance in magnetoelectrodeposition were theoretically clarified.Electrodeposition in a vertical magnetic field induces a macroscopic fluid rotation called vertical MHD flow(VMHDF)over the electrode surface.Inside the rotation,minute numerous micro-vortexes called micro-MHD flow(MMHDF)arise from 2D and 3D nucleation,which interact with the mass flux of metallic ion,yielding chiral deposits with the characteristic features called micro-and nano-mystery circles.Generally,numerous vortexes always keep chiral symmetry,forming four types of vortexes,i.e.,with the combination of upward or downward and clockwise or counterclockwise.However,ionic vacancy acting as an atomic scale lubricant is created in electrodeposition,which gives a restriction to the vortexes;the bottom of an upward vortex covered with ionic vacancies becomes a free surface without friction,whereas the bottom of a downward vortex exposed without ionic vacancies remains rigid with friction.The rotation of VMHDF donates a precession to the upward vortexes to rotate in the same direction,which finally yield a chiral deposit.The similar effect to that of VMHDF can be expected for the system rotation(SR),where an electrolytic cell rotates in a vertical magnetic field.In this case,the SR gives the reverse rotation to the upward vortexes,so that a deposit with reverse chirality is obtained.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号