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   433篇
  免费   4篇
  国内免费   1篇
电工技术   5篇
综合类   2篇
化学工业   54篇
金属工艺   6篇
机械仪表   17篇
建筑科学   32篇
矿业工程   1篇
能源动力   1篇
轻工业   196篇
无线电   6篇
一般工业技术   32篇
冶金工业   14篇
自动化技术   72篇
  2019年   2篇
  2016年   2篇
  2014年   3篇
  2013年   97篇
  2011年   9篇
  2010年   4篇
  2009年   4篇
  2008年   7篇
  2007年   9篇
  2006年   14篇
  2005年   9篇
  2004年   11篇
  2003年   11篇
  2002年   10篇
  2001年   6篇
  2000年   6篇
  1999年   2篇
  1998年   10篇
  1997年   17篇
  1996年   10篇
  1995年   13篇
  1994年   14篇
  1993年   8篇
  1992年   3篇
  1991年   5篇
  1990年   7篇
  1989年   6篇
  1988年   8篇
  1987年   6篇
  1986年   10篇
  1985年   6篇
  1984年   7篇
  1983年   8篇
  1982年   2篇
  1981年   7篇
  1980年   3篇
  1979年   2篇
  1978年   5篇
  1977年   8篇
  1976年   4篇
  1975年   5篇
  1974年   8篇
  1973年   5篇
  1972年   2篇
  1971年   5篇
  1968年   9篇
  1967年   10篇
  1964年   3篇
  1962年   3篇
  1960年   2篇
排序方式: 共有438条查询结果,搜索用时 15 毫秒
101.
The influence of trypsin action in yoghurt milk on the release of caseinophosphopeptide (CPP)-rich fractions was studied and the physical properties of the fermented products determined. Trypsin treatment of skim milk led to increased fermentation times and a substantially lowered production of l -lactic acid as well as to delayed and reduced proteolysis caused by peptidases of the starter cultures. The functional properties of the milk proteins were decreased and the sensory properties less pronounced in yoghurt from trypsin-treated milk, but were described as less bitter than samples from nontreated milk. The CPP sequences β-CN(1–25)-4P and α s1 -CN(43–79)-7P were released during enzyme treatment.  相似文献   
102.
正集聚的目的是使纤维在即将加捻之前彼此既平行又非常接近地排列,这种设置纤维的方式将使集聚纺纱具有其特有的性能,纺纱三角区的消除仅仅是这种设置的一个结果。以下尝试解释在集聚区发生的实际情况。所有成功的集聚纺纱系统都具有以下特点:a)在正常的三罗拉牵伸系统的出口与钳口线之间有一个集聚区;b)这个区域由一个带集聚槽的吸风管组成,集聚槽倾斜于纱线路径的方向,集聚槽内施加了负压;c)一个带网眼器材的输送方法(如网格圈或  相似文献   
103.
Field vines of cv. Sultana, grown either on their own roots, or grafted to a range of rootstocks, were drip‐irrigated at three salinity levels (0.40, 1.75 and 3.50 dS/m) over a five‐year period. Rootstocks comprised Ramsey, 1103 Paulsen, J17‐69 and 4 hybrids (designated R1, R2, R3 and R4) derived from parentage involving Vitis champini, V. berlandieri and V. vinifera. Concentrations of Cl, Na+, K+, Ca2+ and Mg2+ were measured in petioles at flowering, and in laminae and grape juice at harvest, in each year of the trial. Vines on all rootstocks accumulated less chloride in either petioles at flowering or in laminae and juice at harvest compared with vines on own roots at all salinity treatments. By inference, all rootstocks behaved as chloride excluders relative to the roots of own‐rooted vines. 1103 Paulsen was the best chloride excluder based on lowest concentrations of accumulated Cl in petioles, laminae and grape juice at high salinity. Sultana on R3 rootstock at high salinity accumulated more Na+ in both laminae and grape juice (at harvest) than did Sultana on own roots or on any of the other rootstocks. Laminae K+ at harvest time was reduced at high salinity in Sultana on own roots and on all rootstocks. Concentrations of both Cl and Na+ in petioles at flowering and in laminae and grape juice at harvest showed no significant correlation with either yield (as kg of fresh grapes per vine) or vigour (as measured by fresh weight of one‐year‐old pruning wood per vine) for any salinity treatment. There was however, a strong positive correlation between yield and the subsequent weight of one‐year‐old pruning wood for all salinity treatments. There was also a negative correlation between Na+ concentrations in petioles at flowering and the subsequent weight of one year‐old‐pruning wood from the 0.40 dS/m treatment. Similar negative correlations were found between Na+ concentration in both laminae and grape juice at harvest time, and the subsequent weight of one‐year‐old pruning wood from the 0.40 dS/m treatment (but not from either the 1.75 or 3.50 dS/m treatments). Based on these findings and those from Walker et al. 2002a we conclude that a high innate vigour of a rootstock combined with moderate to high chloride and sodium exclusion ability represents the best combination for salt tolerance in Sultana grapevines as measured by yield at moderate to high salinity.  相似文献   
104.
105.
The objective of this study was to examine the effect of reducing sodium chloride (salt) on sensory and processing properties of chunked and formed ham. Chunked and formed hams were made with 0, .5, 1, 1.5 and 2% added salt. Results indicate that the 1.5% salt treatment possessed characteristics closely resembling the 2.0% salt treatment; however, the 1.5% salt treatment had slight reductions in yield, breaking force, and visual acceptability. Reduction of salt from 2.0% to 1.0% resulted in lower yield and sensory characteristics. Additional reductions in the level of salt below 1.0% further depressed yield and sensory characteristics.  相似文献   
106.
A brief review of the reproductive system of the grapevine is presented. Phases discussed include floral induction and initiation during early spring, inflorescence primordium growth during summer to dormancy, flower formation at budburst in the subsequent growing season, and finally flowering and berry development. Difficulties in clearly defining and describing some of these developmental stages will be outlined, especially the complex bud system, the morphology of buds at budburst, and the course of flowering. The course of floral development during dormancy and at the time of budburst requires further attention, especially the reported effect that low temperature at budburst leads to increased numbers of flowers. Also, the recent finding that 'intercarpellar' floral organs can be induced by applying auxin is of particular interest and will be described. Case studies from Burgundy vineyards with Chardonnay, Pinot Noir and Gamay ovaries and berries will be included.
A detailed analysis of what constitutes a grape bunch will be presented from observations of Chardonnay inflorescences and bunches collected at random after set and at harvest in two seasons from spur-pruned, cane-pruned and hedged vines growing on two sites varying in climate and productivity (Adelaide Hills and Southern Vales of South Australia). This analysis covered variability in numbers of branches and flowers and in per cent berry set, as well as relationships between branch numbers and flower numbers. Relationships between flower numbers and per cent set, per cent set and berry size along the inflorescence, and berry size and seed complement are outlined. Likely implications of inter-bunch and intra-bunch variability for bunch compactness, berry composition and yield components are discussed.  相似文献   
107.
No Resistance     
In 2006, Peter Lynch (USA) and Gustavo Crembil (Argentina/USA) established THEM, an architectural partnership, after several years of a collaborative practice drawing upon the fields of design, architecture, performance art, communication, and social and ecological activism. The "Pleasure Garden," THEM's proposal for the 2008 YAP PS1/MoMA competition, continues an exploration of "craft in the age of globalization" and suggests what such an architecture might look like.  相似文献   
108.
A five parameter semi-empirical model is developed describing the apparent viscosity of a cooking dough as a function of applied shear rate, temperature, and time-temperature history. Such a model will be useful in the mathematical simulation of the extrusion cooking process. Other factors which can affect the apparent viscosity of a cooking dough are also discussed. The viscosity model is verified and the constants evaluated for a typical dough by combining the results of Amylograph and capillary viscometer experiments.  相似文献   
109.
This paper presents the theoretical and methodological background and main findings of the research project “A System Dynamics Model of Slovakia,” which was financed by the Austrian Ministry of Science and Research. It was performed by cooperative efforts of scientists at INFO-STAT, Bratislava, and the Department for Design and Assessment of Technology/Social Cybernetics at the Vienna University of Technology. The model deals with the transition of Slovakia from a centrally planned to a market economy for the period 1990 to 1996. As examples of its application, the standard run and a scenario to fight unemployment are discussed.  相似文献   
110.
Abstract

Studies on microwave surface scattering in The Netherlands have indicated the need for accurate radar systems for applications in remote sensing. An SLAR system with digital recording was developed and is now being used for several programmes. This system was designed with special attention to speckle reduction and system accuracy. The digital data are processed in a computer with algorithms for geometric and radiometric corrections. In the future aircraft position and attitude measurements will also be used in these correction algorithms. Examples of the results are shown.  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