全文获取类型
收费全文 | 226篇 |
免费 | 7篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 33篇 |
金属工艺 | 1篇 |
机械仪表 | 1篇 |
建筑科学 | 25篇 |
能源动力 | 8篇 |
轻工业 | 33篇 |
水利工程 | 4篇 |
无线电 | 24篇 |
一般工业技术 | 26篇 |
冶金工业 | 27篇 |
自动化技术 | 50篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 7篇 |
2013年 | 13篇 |
2012年 | 9篇 |
2011年 | 25篇 |
2010年 | 12篇 |
2009年 | 7篇 |
2008年 | 20篇 |
2007年 | 11篇 |
2006年 | 10篇 |
2005年 | 12篇 |
2004年 | 14篇 |
2003年 | 8篇 |
2002年 | 12篇 |
2001年 | 8篇 |
2000年 | 3篇 |
1999年 | 8篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1982年 | 2篇 |
1978年 | 1篇 |
排序方式: 共有233条查询结果,搜索用时 15 毫秒
11.
Kees van Malssen Arjen van Langevelde René Peschar Henk Schenk 《Journal of the American Oil Chemists' Society》1999,76(6):669-676
A complete isothermal phase-transition scheme of cocoa butter under static conditions is presented, based on time-resolved
X-ray powder diffraction experiments. In contrast to what is known from literature, not only β V, but also β VI can be obtained
directly through transformation from β′. Another remarkable result is that β′ exists as a phase range rather than as two separate
phases. Within this β′ phase range no isothermal phase transitions have been observed. More detailed information concerning
the observed cocoa butter polymorphs was obtained by determination of melting ranges, using time-resolved X-ray powder diffraction.
Also standard X-ray powder diffraction patterns of the γ, the α, and the two β phases and parts of the β′ phase range have
been recorded. The observed phase behavior of cocoa butter has been explained based on the concept of individual crystallite
phase behavior of cocoa butter 相似文献
12.
Van Roosbroeck S Hoek G Meliefste K Janssen NA Brunekreef B 《Environmental science & technology》2008,42(4):1337-1344
The validity of traffic intensity near the home as an estimate for the personal long-term exposure to traffic-related air pollution in an adult population was tested. Personal and near-home outdoor exposure to PM2.5, soot, NO, NO2, and NOx was monitored four to five times during 48 h periods in older adults. A group of 23 participants lived in high traffic intensity streets (>10000 vehicles/(24 h)), and 22 lived in low traffic intensity streets. The relation between average personal exposure and traffic intensity at the residential address was explored by taking indoor sources into account. Large differences in the measured outdoor concentrations between locations in high traffic and low traffic intensity streets were found for soot (68%), NO (127%), and NOx (35%). Differences were smaller for PM2.5 (14%) and NO2 (22%). Slightly elevated ratios were found for personal exposure to soot (1.15; 95% confidence interval (CI), 1.01-1.30)when comparing adults living in high traffic intensity streets with adults living in low traffic intensity streets. For NO, increased personal exposure (1.16) was seen for the same comparison, but this difference failed to reach statistical significance (CI, 0.80-1.66). Traffic intensity on the street of residence predicted personal exposure to soot but not to PM2.5 or nitrogen oxides. Traffic intensity may not correlate well to personal exposure and accordingly substantial misclassification of exposure may occur when traffic intensity is used as an exposure indicator in epidemiological studies. Time spent in traffic and spending time outdoors were associated with increased personal exposure of soot and PM2.5, but not NOx. 相似文献
13.
Abstract This paper analyzes the transformation of river basin management in South Africa by focusing on the political processes involved in the creation of new water management bodies and irrigation infrastructure in the Lower Komati sub-basin. Institutional reform is described and analyzed in terms of the collaboration theory of Gray (1985). Attention is paid to the absence of mutual collaboration in the water domain through the analysis of three phases that are characteristic of collaborative management: problem setting, direction setting, and structuring. The perceptions and strategies of stakeholders in the change process are informed by the skewed access to land and water, the protracted struggle for redress of historical inequities, the quest for autonomy in water management by commercial farmers, and large political power differentials. This has resulted in differential access to decision making and political influence and in the materialization of these skewed relations in water control technology. The reluctance of stakeholders to explicitly recognize their interdependence and the role of the state as the convener of the change process has hampered the emergence of a shared appreciation of the problems in the water domain. Despite efforts by government to move towards equitable and inclusive water management, little redress of past inequities has taken place, and the majority of small farmers are uninformed and excluded from the change process. This suggests that the proposed Catchment Management Agency will not be representative nor attain equitable water management unless a well-conceived redistribution of water entitlements and land rights is carried out as part of an encompassing program to strengthen political democracy. 相似文献
14.
ABSTRACTThis article explores how private owners can protect bodies of water through private property rights. It compares the use of conventional property rights in the Netherlands and New Zealand with a novel approach whereby a New Zealand river owns itself. 相似文献
15.
16.
Marthen L. Ndoen Kees Gorter Peter Nijkamp Piet Rietveld 《The Annals of Regional Science》2002,36(3):421-436
This paper aims to investigate the entrepreneurial migrants' preferences for a location for business activities in developing
countries. In the modelling framework six socio-economic and six socio-cultural variables are used in this study to investigate
the migrants' propensity to stay at a particular region. The empirical research was carried out in East Nusa Tenggara, Indonesia.
It appears that the presence of a supporting informal network is the most critical factor that attracts and keeps the entrepreneurial
migrants in a particular region. Socio-cultural variables like experience and education play a less significant role in the
migrants' decision to stay in a given region.
RID="*"
ID="*" Kees Gorter passed away in October 2001. 相似文献
17.
Emission, fate and effects of soluble silicates (waterglass) in the aquatic environment 总被引:2,自引:0,他引:2
van Dokkum HP Hulskotte IH Kramer KJ Wilmot J 《Environmental science & technology》2004,38(2):515-521
Soluble silicates, commercially known as waterglass, are among the largest volume synthetic chemicals in the world. Silicon from waterglass is rapidly transformed to the biologically active orthosilicic acid (referred to as dissolved silicate). This paper aims to assess the impact of waterglass on the aquatic environment in Western Europe. The emission to surface waters from the four most relevant application areas, household detergents, pulp and paper production, water and wastewater treatment, and soil stabilization, is estimated to be ca. 88-121 kton of SiO2 per year. This is a small fraction (<2%) of the estimated total amount of dissolved silicate transported by rivers to the oceans. Locally, increases in dissolved silicate concentration will decrease the ratios of N:Si and P:Si, which could influence phytoplankton species composition and favor the growth of diatoms over other groups of algae. Significant adverse effects in aquatic ecosystems are not expected. 相似文献
18.
Edzer Huitema Gerwin Gelinck Bas van der Putten Eugenio Cantatore Karel Kuijk Kees Hart Dago De Leeuw 《Journal of the Society for Information Display》2002,10(3):195-202
A 2‐in. active‐matrix display was demonstrated, containing 4096 solution‐processed polymer‐based transistors. By using the polymer‐dispersed liquid‐crystal display (LCD) effect, this results in a reflective, low‐power display with paper‐like contrast. The influence of the transistor parameters on the display performance is analyzed by use of a model for charging and discharging of the pixel capacitors. Good agreement was obtained between the model and the experimental data. Scaling behavior allows estimation of the performance required for transistors in a quarter‐VGA display. These requirements are met by solution‐processed pentacene transistors. 相似文献
19.
Frido E. Smulders Harry Boer Poul H.K. Hansen Ebbe Gubi Kees Dorst 《Creativity & Innovation Management》2002,11(1):62-73
This paper describes and illustrates different configurations of the interface between new product development and production processes, including both intra–firm and inter–firm interfaces. These configurations are partly based on a process view of product innovation and partly on a structural view of product innovation. In addition to this typology of interfaces some integration mechanisms are described. The typology will serve as a basis for further research aimed at identifying consistent configurations of the different types of integration mechanisms that are available for industry to increase the effectiveness and efficiency of product innovation processes. 相似文献
20.
Development of adolescent reading comprehension in language 1 and language 2: A longitudinal analysis of constituent components. 总被引:1,自引:0,他引:1
van Gelderen Amos; Schoonen Rob; Stoel Reinoud D.; de Glopper Kees; Hulstijn Jan 《Canadian Metallurgical Quarterly》2007,99(3):477
This study investigated the relationship between reading comprehension development of 389 adolescents in their dominant language (Language 1 [L1], Dutch) and a foreign language (Language 2 [L2], English). In each consecutive year from Grades 8 through 10, a number of measurements were taken. Students' reading comprehension, their linguistic knowledge (vocabulary and grammar knowledge) and processing efficiency (speed of word recognition and sentence comprehension) in both languages, and their metacognitive knowledge about reading were assessed. The relative strengths of the effects of these components of reading were analyzed to distinguish among 3 hypotheses about the relationship between L1 and L2 reading comprehension: the transfer hypothesis, the threshold hypothesis, and the processing efficiency hypothesis. The transfer hypothesis predicts a strong relationship between L1 and L2 reading comprehension and a strong effect of metacognitive knowledge on L2 reading comprehension, whereas the threshold and processing efficiency hypotheses predict a more important role of language-specific knowledge and processing skills. Results support the transfer hypothesis, although language-specific knowledge and fluency also contribute to L2 reading performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献