全文获取类型
收费全文 | 166篇 |
免费 | 11篇 |
专业分类
化学工业 | 61篇 |
金属工艺 | 1篇 |
机械仪表 | 2篇 |
建筑科学 | 10篇 |
能源动力 | 8篇 |
轻工业 | 16篇 |
石油天然气 | 12篇 |
无线电 | 4篇 |
一般工业技术 | 13篇 |
冶金工业 | 23篇 |
自动化技术 | 27篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 8篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 17篇 |
2012年 | 6篇 |
2011年 | 7篇 |
2010年 | 6篇 |
2009年 | 14篇 |
2008年 | 6篇 |
2007年 | 13篇 |
2006年 | 7篇 |
2005年 | 2篇 |
2004年 | 6篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1989年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1964年 | 1篇 |
1958年 | 1篇 |
1933年 | 2篇 |
排序方式: 共有177条查询结果,搜索用时 15 毫秒
171.
Lovaas O. Ivar; Koegel Robert L.; Schreibman Laura 《Canadian Metallurgical Quarterly》1979,86(6):1236
Reviews a series of investigations that suggest that autistic children show "stimulus overselectivity," a response to only a limited number of cues in their environment, and discusses how such overselectivity may relate to several of the behavioral deficits in autism. These include failure to develop normal language or social behavior, failure to generalize newly acquired behavior to new stimulus situations, failure to learn from traditional teaching techniques that use prompts, and a general difficulty in learning new behaviors. Several studies that suggest possible remedial procedures are discussed, and the concept of stimulus overselectivity is related to the literature on attentional or response deficits in adult schizophrenia, mental retardation, learning disabilities, and autism. (2? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
172.
Politically speaking, the most striking feature of the planned reorganization of Swedish broadcasting is a further decentralization and localization of production. 相似文献
173.
Enhanced fracture toughness in nonstoichiometric magnesium aluminate spinel through controlled dissolution of second phase alumina
下载免费PDF全文
![点击此处可从《Journal of the American Ceramic Society》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jesse A. Miller Ivar E. Reimanis Marc R. Du Merac 《Journal of the American Ceramic Society》2018,101(2):812-820
Dissolution of Al2O3 particles into a MgAl2O4 (spinel) matrix is accompanied by a volumetric expansion that is predicted to lead to a compressive stress field upon cooling, resulting in a promising microstructure for enhanced toughening of transparent spinel. This study explores the conditions to form such a microstructure by hot‐pressing powders of Al2O3 and spinel, at temperatures that promote dissolution of the Al2O3. Tough, particulate‐reinforced composites were formed under lower temperatures and shorter times, but single phase, cubic spinel was formed at 1700°C for 10 hours. The single phase spinel made in this way exhibited a toughness of 2.26 ± 0.17 MPa√m, significantly higher than the equivalent nonstoichiometric spinel made by traditional methods, 1.72 ± 0.06 MPa√m. X‐ray diffraction measurements revealed lattice parameter changes consistent with the dissolution of Al2O3 into spinel. Mechanics modeling reveals that toughening arises due to the volume expansion as Al2O3 dissolves into the spinel matrix. 相似文献
174.
Autofluorescence spectra have been obtained on beef longissimus dorsi muscles (n=151), and the spectra regressed against Warner-Bratzler (WB) peak values. The spectra obtained depended on the method used, and it is suggested that the difference is related to the use of two different types of Xenon lamps (a pulsed versus a continuous light source) and the inherent kinetic differences in the collection of the fluorochromes' emitted light. Poor to good (R=0.45-0.84) correlations between WB peak values and the emission spectra were obtained. This relationship is established using chemical information originating largely from collagens. Minor differences in predictability were observed using either excitation wavelengths 332 or 380?nm. The emission wavelengths containing the most relevant information about WB peak values were between 360 and 500 nm. Wavelengths around 375 nm, excitation 332 nm, were in particular important and were related to a component in the perimysial tissue, most likely being present in collagen I or III. Excitation at 380?nm revealed the wavelength range 460-480?nm as important presumed due to collagens in the perimysium. An experiment, simulating industrial routines, using 45 samples collected at the slaughterhouse two days post mortem, was carried out. However, for those samples no model was observed between the emission spectra and WB peak values. Only when some samples having very low (1.45?μm) sarcomere lengths were removed, could a significant model be obtained. It is concluded that with the prevailing early post mortem routines in slaughterhouses with, among other things, wide variation in chilling rates between muscles and carcasses, the technique of autofluorescence has limited industrial potential as a sole, rapid non-destructive method for measuring tenderness of the longissimus dorsi muscle (LD). 相似文献
175.
Tomas Isaksson Geir Tgersen Arve Iversen Kjell Ivar Hildrum 《Journal of the science of food and agriculture》1995,69(1):95-100
Near infrared (NIR) diffuse spectroscopy was used to determine the fat, moisture and protein contents in whole and ground farmed atlantic salmon fillets. A remote fibre-optic probe was used for NIR measurements on 50 whole salmon fillets. The constituent ranges were: 91-205 g kg?1 fat, 599-709g kg?1 moisture and 186-209 g kg?1 protein. Principal component regression resulted in the following prediction errors for ground salmon fillets, expressed as root mean square error of cross validation: 6.6 g kg-1 fat, 3.8 g kg?1 moisture and 2.0 g kg?1 protein. The corresponding prediction errors for non-destructive measurements on whole salmon fillets were 10.8 g kg?1 fat, 8.5 g kg?1 moisture and 3.7 g kg?1 protein. Regression models using the 760-1100 m range gave lower prediction errors than models using the 1100-2500 mm or 760-2500 nm ranges. The results show that fibre-optic probe NIR instruments are suited to determine fat and moisture in whole salmon fillets non-destructively. 相似文献
176.
Bente Kirkhus Amandine Lamglait Ivar Storrø Gjermund Vogt Elisabeth Olsen Frank Lundby Håkon Standal 《Journal of the American Oil Chemists' Society》2015,92(2):215-223
The thermal stability of liquid margarine and vegetable oils was investigated by measuring the oxidative stability index (OSI) at temperatures ranging from 90 to 180 °C, whereas total polar compounds (TPC) and tocopherols (vitamin E) were measured during heating at 180 °C in frying trays. Results showed that the OSI of liquid margarine was in the same range as the OSI of vegetable oils at lower temperatures, but at 160 and 180 °C, liquid margarine had significantly higher thermal stability, close to that observed for hard margarine and butter. The increased stability was confirmed by lower levels of TPC and a smaller relative reduction in vitamin E content during heating. Variations between different vegetable oils could partly be explained by differences in degree of saturation and level of vitamin E, with high oleic sunflower oil being the most stable oil at all temperatures. The water in liquid margarine vaporized within 1.5 min at 160 °C, and it is hypothesized that volatile pro‐oxidants are removed with the water, inducing a delay in deterioration. The results indicate a role for water in preventing lipid oxidation and decomposition in fat emulsion products at 160–180 °C, suggesting that liquid margarine, low in saturated fat, may be the healthier and preferable alternative for pan‐frying compared to other liquid vegetable oils. 相似文献
177.