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   180篇
  免费   9篇
  国内免费   7篇
电工技术   20篇
综合类   1篇
化学工业   49篇
金属工艺   15篇
机械仪表   10篇
建筑科学   5篇
能源动力   9篇
轻工业   17篇
无线电   3篇
一般工业技术   28篇
冶金工业   11篇
原子能技术   6篇
自动化技术   22篇
  2022年   1篇
  2021年   1篇
  2019年   1篇
  2018年   6篇
  2017年   3篇
  2016年   6篇
  2015年   4篇
  2014年   5篇
  2013年   26篇
  2012年   5篇
  2011年   13篇
  2010年   7篇
  2009年   6篇
  2008年   8篇
  2007年   6篇
  2006年   11篇
  2005年   7篇
  2004年   8篇
  2003年   5篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1999年   2篇
  1998年   6篇
  1997年   10篇
  1996年   2篇
  1995年   2篇
  1994年   4篇
  1993年   2篇
  1992年   2篇
  1990年   3篇
  1989年   4篇
  1988年   1篇
  1987年   5篇
  1986年   3篇
  1985年   1篇
  1984年   2篇
  1983年   3篇
  1981年   1篇
  1980年   3篇
  1979年   4篇
  1976年   2篇
排序方式: 共有196条查询结果,搜索用时 15 毫秒
31.
Plasma protein was conjugated with galactomannan (GM) in a controlled dry state at 60°C and 79% relative humidity. The covalent attachment of GM to plasma protein was confirmed by SDS-PAGE and gel chromatography. Emulsifying activity of plasma protein-GM complex was 1.4 times and the emulsion stability of the complex was more than 10 times higher than those of plasma protein. In acidic (pH 3) and salt (0.2M NaCl) systems, the complex showed much more effective emulsifying properties than did commercial emulsifiers. Emulsifying properties of the complex were retained after preheating at 80°C for 30 min. Plasma protein-GM complex prepared by Maillard reaction during heating in a dry state could be used for heat-processed foods as a protein emulsifier.  相似文献   
32.
A new method was established to estimate the foaming properties of proteins from the conductivity of foams using a simple apparatus that consisted of a glass column with the conductivity cell. A close correlation was observed between the initial conductivity of foams and the foam volumes of heat-denatured ovalbumins or 11 native proteins, suggesting that the initial conductivity of foams can be used as a measure of foaming power. In addition, a close correlation was obtained between the foam stability determined from changes in the conductivity and foam volume with time of heat-denatured ovalbumins or 11 native proteins, suggesting that foam stability also can be estimated from changes in the conductivity of foams. The advantages of the conductivity measurements are to determine the foaming properties more simply and accurately than the currently used methods.  相似文献   
33.
在测试应力范围内,SiCW/6061Al复合材料在196℃显示循环蠕变加速而在350℃显示循环蠕变减速在0~0.5Hz范围内,随着频率的增加,温度较低时循环蠕变应力指数增加而激活能降低,温度较高时应力指数与激活能同时增加当频率增加到1Hz时则偏离上述趋势  相似文献   
34.
The heat capacity of C70 has been measured by adiabatic calorimetry between 14 and 320 K. The orientational phase transition is observed as a broad hump in the heat capacity curve, which is strongly influenced by small amount of solvent remaining in the sample.  相似文献   
35.
小林贤二,1964年出生于日本长野县,1993年成立小林贤二工作室。他善长运用土、石、水、植物等自然素材创造庭院空间和艺术作品,其设计分布于公共空间、商业设施、公寓和住宅区等领域。小林贤二非常热爱这个由土、石、水和绿色覆盖的地球。在这里,生命感受着风和阳光,在季节更替中生长、变化。  相似文献   
36.
Into neutral : We demonstrate the unique features of a pH click peptide based on an O‐acyl isopeptide method. Under acidic conditions, the click peptide remains in a monomeric form. Upon increase of the pH to 7.4, the click peptide is quickly able to convert into Aβ1–42 through an O‐to‐N intramolecular acyl migration. Further study using this pH click peptide would elucidate the pathological role of Aβ1–42 in Alzheimer's disease.

  相似文献   

37.
Electrical conductivity due to halide ions has been measured for the glasses in the system 30SiO2· (70 − x )PbO · x PbX2 (0 < x < 17.2 mol%; X = F, Cl). The conductivity increases with x by several orders of magnitude for both series of glasses. The contribution of principal factors to the conductivity has been examined. The analysis of the activation energy on the basis of the Anderson-Stuart model shows that the strain energy is a predominant term in the Cl glasses, while both the strain energy and the electrostatic energy have a comparable contribution in the F glasses. The decrease in the activation energy with increasing PbX2 content is related to the decrease in the shear modulus for the Cl glasses and to the increase in the permittivity for the F glasses.  相似文献   
38.
The shell structure of the Bivalvia has been observed with the use of optical and electron microscopes since the early 1900’s. The prismatic structure is one of the more attractive shell structures in bivalved mollusks. This structure is composed of the aggregation of polygonal prisms arranged densely. Each prism is made of small calcite crystallites arranged perpendicular to a growth shell surface. Organic materials, named organic sheaths, accumulate around prisms and stain well with heamatoxylin-eosin. The Bivalvia, which make prismatic structures, are divided into two groups. One group has the inner shell layer made up of a nacreous structure, and the other has the inner shell layer made up of a foliated structure. The aragonite prismatic layer and the prismatic layer are closely related to each other, as is the aragonite prismatic layer to the composite prismatic one.  相似文献   
39.
The Pt coating (Pt-C) process has been developed to lower the recontamination by radioactive elements after chemical decontamination of piping surfaces. In this process, a layer of fine Pt nano particles is formed in an aqueous solution on the base metal of the piping following the chemical decontamination. In this study, we confirmed that the suppression effect by the Pt-C toward 60Co deposition on type 316 stainless steel using a 60Co deposition test under hydrogen water chemistry. Furthermore, we investigated the suppression mechanism of deposition of radioactive elements by a quantum molecular simulation. The deposition amounts of 60Co which were incorporated in oxides after 1000 h with and without the Pt-C process were about 90 and 10.2 Bq/cm2, respectively. The amount of 60Co deposition with Pt-C is about 10% that of non-coated specimens. The 60Co incorporation for the Pt-C specimen was suppressed by decreasing the formation of oxides. We considered this phenomenon using a quantum dynamics calculation and concluded that the Fe–O bonds in oxides were weakened by the effect of Pt and hydrogen radicals which were produced in the reaction between H2 and Pt, and then oxides were dissolved into the water.  相似文献   
40.
松油烯与马来酸酐的Diels-Alder反应的研究   总被引:2,自引:0,他引:2  
研究了松油烯与马来酸酐的分子间Diels-Alder环加成反应和松油烯的异构转化行为。使用相对于α-松油烯过量的马来酸酐,相对于α-松油烯而言,在65~70℃二时有大约15%,在100~105℃下有38%,在135~140℃时有69%的松油烯异构转化率。同样在65~70℃和100~105℃温度下,矾土、活性白土、硅胶、离子交换树脂、对甲基苯磺酸催化下,大约有20%~77%的异构转化率。用异核远距离关联(HMBC)等核磁共振测试手法解析了环加成产物的结构,归属了各原子的化学位移。  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