全文获取类型
收费全文 | 175篇 |
免费 | 3篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 11篇 |
金属工艺 | 38篇 |
机械仪表 | 5篇 |
建筑科学 | 2篇 |
轻工业 | 13篇 |
无线电 | 16篇 |
一般工业技术 | 44篇 |
冶金工业 | 35篇 |
原子能技术 | 5篇 |
自动化技术 | 7篇 |
出版年
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 3篇 |
2013年 | 13篇 |
2012年 | 11篇 |
2011年 | 11篇 |
2010年 | 8篇 |
2009年 | 13篇 |
2008年 | 10篇 |
2007年 | 7篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 6篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 8篇 |
1997年 | 2篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1966年 | 1篇 |
1963年 | 1篇 |
1959年 | 1篇 |
1957年 | 2篇 |
1954年 | 1篇 |
排序方式: 共有178条查询结果,搜索用时 15 毫秒
61.
Blood and milk samples from Holstein cows were examined for total blood leucocyte count, differential blood leucocyte count, milk quality test, and somatic cell count in milk while the cows were stressed by corticotropin injection, confinement in a heat-humidity chamber, or environmental-heat stress by exposure during the hot summer months of June through November in southern Arizona. All three stressing conditions resulted in a moderate blood leucocytosis. Modest increases in somatic cell counts of milk were associated with corticotropin injection and environmental-heat stress. Positive correlations were recorded between blood leucocytes and somatic cell counts of milk in mastitis-free cows injected with corticotropin and between percent blood neutrophils and somatic cell counts of milk in environmental-heat stressed cows with no evidence of current mastitis. 相似文献
62.
H. Schuh 《Forschung im Ingenieurwesen》1954,20(2):37-47
Zusammenfassung Es wird eine Integralform der Grenzschichtgleichung sowohl für Str?mungs- als auch für Temperaturgrenzschichten verwendet,
zu deren L?sung nur Quadraturen vorzunehmen sind. Die Neuheit des Verfahrens besteht in der Wahl der abh?ngingen Ver?nderlichen
beim Berechnen des Temperaturfeldes. Behandelt wurden F?lle konstanter und ver?nderlicher Wandtemperatur sowie vorgegebenen
W?rmeflussen an der Wand unter der Voraussetzung, da? die Stoffwerte konstant sind und da? von der Reibungsw?rme abgesehen
werden kann; jedoch ist es m?glich, diese Vernachl?ssigungen durch eine passende Wahl der Bezugstemperaturen zu berücksichtigen.
Beispiele und Vergleiche mit Versuchen werden gegeben.
Gekürzte Fassung eines Berichtes aus dem Flugtechnischen Institut der Technischen Hochschule Stockholm: A new method for calculating
laminar heat transfer on cylinders of arbitrary cross-section and on bodies of revolution at constant and variable wall temperature.
Roy. Inst. Technol. Div. Aero., KTH AERO TN. 33. Stockholm 1953. 相似文献
63.
T. Schenkel C.C. Lo A. Schuh J. Bokor 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(16):2563-2566
The formation of quantum computer test structures in silicon by ion implantation enables the characterization of spin readout mechanisms with ensembles of dopant atoms and the development of single atom devices. We briefly review recent results in the characterization of spin dependent transport and single ion doping and then discuss the diffusion and segregation behaviour of phosphorus, antimony and bismuth ions from low fluence, low energy implantations as characterized through depth profiling by secondary ion mass spectrometry (SIMS). Both phosphorus and bismuth are found to segregate to the SiO2/Si interface during activation anneals, while antimony diffusion is found to be minimal. An effect of the ion charge state on the range of antimony ions, 121Sb25+, in SiO2/Si is also discussed. 相似文献
64.
A feed preference agent, Firanor-242, was added (0, 50, or 100 ppm) to whole milk and starter ration to determine if association of it with milk would enhance starter intake and weaning performance in dairy calves. Thirty 1-day-old Holstein calves (six males, four females per treatment) each received 1.6 kg of milk twice daily to 30 days of age and starter ration from 7 to 40 days of age. There were no differences from treatments in daily feed intake or body weight gains.In a paired comparison preference test for Firanor-24 in milk, two groups of five unnursed newborn calves were preconditioned to 0 or 100 ppm Firanor-24 in colostrum at birth and in milk twice daily for 6 days. In the 5-day test period each calf was offered a choice of milk with 0 or 100 ppm randomized in two adjoining buckets. No differences in milk preference were observed. 相似文献
65.
One or the main challenges for production enterprises is succeeding in the dynamic competitive environment with its rapidly changing requirements. A strategy for the individual factory to cope with these turbulent market and technological developments is to focus itself on a specific set of competencies and capacities and to offer these within the framework of temporary production networks which can be rapidly configured to meet changing requirements. Therefore, the individual factory must be able to integrate itself into temporary partnerships for changing production tasks but at the same time retain a stable basis for the efficient utilisation and sustainable development of its own capacity and competence. The developed object oriented explanation model is based on object oriented software engineering principles and describes an approach for the initial configuration and reconfiguration of factories within the framework of collaborative production networks. 相似文献
66.
Today’s turbulent economic environment confronts Germany’s tooling industry with new challenges. To compete with China and
with the new eastern members of the European Union, German companies must come up with innovative products and services to
stand out from their competitors. New types of business models shall offer individual solutions to the customers, integrating
product and accompanying product-services to a product-service-system. 相似文献
67.
In this study, the author describes the nature and occurrence of knowledge-construction links (KCLs) in 3 6th-grade classrooms that varied in degree of learner centeredness. KCLs are operationalized as prior learning that students bring to their current classroom experiences and include school and nonschool experiences. They are hypothesized to facilitate a knowledge-construction process that values prior learning. In the more learner-centered classroom, KCLs occurred in conjunction with open and divergent dialogue, positive reactions to students' use of prior learning, and opportunities within the classroom that allowed students to gain new experiences on which they could draw in further knowledge-construction efforts. In contrast, KCLs were ignored or viewed as inappropriate in the least learner-centered classroom, dialogue about content was convergent, and performance goals were the norm. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
The differences between shame and guilt are explored, with a focus on experiential and developmental factors and on behavioral reactions to these emotions. The role of shame as a motive for suicidal behavior is illustrated with examples of suicidal behavior in Greek tragedy, Asian cultures, and jails, and among contemporary suicides, such as that in 1996 by Admiral Mike Boorda, Chief of U.S. Naval Operations. 相似文献
69.
G. Schuh 《CIRP Annals》2004,53(1):167-170
This paper presents an innovative approach to augment R&D effectiveness and manage increasing system complexity. Release-Engineering is a principle of software engineering which can be transferred to complex automotive systems. Simulations based on features show significant reduction of internal complexity. Without reduction of necessary marketwise diversity, a time wise bundling of component changes exponentially lowers system complexity. The approach represents a major step towards more significant innovation programmes through suitable, dedicated R&D efforts on system variants. Another meaningful implication of Release-Engineering is its impact on innovation frequency by providing significant increases in innovation rates. 相似文献
70.