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61.
This paper reviews studies on the basic principles of biostimulation of wound healing by various low-energy lasers. It looks at the mechanism of action of biostimulation as well as the laser's effect on cell proliferation, collagen synthesis, and would healing. 相似文献
62.
Choon-Ling Sia Hock-Hai Teo Tan B.C.Y. Kwok-Kee Wei 《Engineering Management, IEEE Transactions on》2004,51(3):253-267
Uncertainty in the external environmental context has been shown to affect organizational change and innovation. Distributed work arrangement is an organizational innovation that has the potential to enable a firm to meet the challenges of an uncertain environment more effectively. With the emergence of virtual organizations, such work arrangements are likely to gain increasing popularity. This exploratory empirical study employs a structural model to examine how environmental uncertainty affects organizational predisposition (adoption intention) toward distributed work arrangements. Environmental uncertainty has two different dimensions: environmental complexity (heterogeneity) and environmental variability (dynamism). In this paper, environmental dimensions are modeled to influence adoption of distributed work arrangements through shaping the organizational perceptions of three innovation characteristics: perceived relative advantage, compatibility and complexity. Data analyses using partial least squares statistical technique revealed that environmental complexity is negatively associated with perceived relative advantage, and perceived compatibility. Perceived relative advantage and perceived compatibility are in turn positively related to adoption intention for distributed work arrangements. However, environmental variability has no significant effect on the three innovation characteristics. Contrary to past findings that suggest organizations are more predisposed toward innovations in a complex environment, our study found that organizations in an environment of lower, rather than higher complexity are more likely to adopt distributed work arrangements. Implications for organizations are discussed. 相似文献
63.
64.
JY Kang KG Yeoh KY Ho R Guan TP Lim SH Quak A Wee D Teo YW Ong 《Canadian Metallurgical Quarterly》1997,12(9-10):655-659
The aim of this study was to determine, first, whether racial differences exist in the seroprevalence of Helicobacter pylori infection in Singapore, and second, whether these differences correlate with racial differences in peptic ulcer frequency. A commercial serological test for immunoglobulin (Ig)G antibody to H. pylori which was 90% sensitive and 83% specific in our population was used to screen 403 adult blood donors of Chinese, Malay and Indian origin, aged between 15-60 years. Serum specimens from 84 paediatric patients admitted to the Paediatrics Department, National University of Singapore, with non-gastroenterological illnesses were also tested. In all three races, seroprevalence of H. pylori increased with age. Indians have the highest prevalence of infection followed by Chinese and Malays. Peptic ulcer prevalences are known to be highest in Chinese, followed by Indians and Malays. The Malays have the lowest prevalence of H. pylori and peptic ulcer among the three races in Singapore. Indians have a higher prevalence of H. pylori antibodies but a lower frequency of peptic ulcer than the Chinese. Racial differences in peptic ulcer frequency between Chinese and Indians are not explained by the prevalence of H. pylori infection; other environmental or genetic factors may be involved. 相似文献
65.
An important aspect in successfully implementing instructional technology in educational settings is user acceptance, which is greatly influenced by users’ attitudes towards computers. Today, computers have become an integral part of instruction at all levels of education and it is important for educators and policy makers to understand how various factors interact with the user’s characteristics to influence the teaching and learning process involving the use of computers. Over the years, many scales have been developed to measure computer attitudes of secondary students and adults. Few have been develop to be used for students in the primary schools. The aim of this study is to develop and validate a computer attitude measure for young students (CAMYS). The revised 12-item CAMYS was piloted with 256 students aged 10–12 with a mean of 11.9 years (SD = 0.31). Several statistical analyses were performed to assess the reliability and validity of the measure. The measure, together with suggestions for administration and scoring are included. 相似文献
66.
Two new series representations for the Rice functionIe (k, x) are presented. One of the series involves the modified Struve functions and the other involves the modified Bessel functions. These two series complement each other in their convergence speeds as functions of the values ofk andx . The truncation error bounds are derived for both series. Therefore, they can be used alternatively with high efficiency and known precision. 相似文献
67.
Although many developing and developed countries have major initiatives to promote the use of information technology (IT), Singapore is one of the few countries which not only has a comprehensive IT2000 vision, but which is also taking proactive steps to make the vision a reality. This paper examines how Singapore is currently leveraging IT applications to achieve the IT2000 vision. It also explores some of the uses of IT that will be deployed in the near future. Specifically, this paper discusses the use of IT applications to provide one-stop, non-stop government and business services, promote cashless transactions, provide more options for leisure, and facilitate easy commuting. 相似文献
68.
A suite of five representative samples from a freshly opened adit in the Fording River Coal Deposits, BC was taken at selected distances from the surface to the 45.7 m depth of the seam to provide material for studying the progress of coal oxidation under natural conditions. The ‘as-mined’ < 28 US mesh material from each sample was subjected to standard proximate, ultimate and free swelling index (FSI) analyses, followed by quantitative evaluation of surface oxidation states, using several techniques concurrently. Correlation of the results indicates a progressive decrease in oxidation from a very high level for the surface sample, with FSI 1, to a relatively low oxidation level for samples taken at 22.9 m and 45.7 m distances. Solvent extracts show a progressive decrease in the ratio of soluble aliphatic-to-aromatic compounds from surface to deep coal and in the amount of carboxylate groups. Oxidized coals require pretreatment with dilute acids in order to convert phenolate and carboxylate salts into phenols and carboxylic acids respectively; the analytical results for the latter are then increased by a factor of 4–6. 相似文献
69.
V Dzavik DS Beanlands RF Davies D Leddy JF Marquis KK Teo TD Ruddy JR Burton DP Humen 《Canadian Metallurgical Quarterly》1994,73(12):856-861
The effect of late percutaneous transluminal coronary angioplasty (PTCA) of an occluded infarct-related artery on left ventricular ejection fraction was studied in patients with a recent, first Q-wave myocardial infarction in a prospective, randomized study. Forty-four patients (31 men and 13 women, mean age 58 +/- 12 years) with an occluded infarct-related coronary artery were randomized to PTCA (n = 25) or no PTCA (n = 19). Patients received acetylsalicylic acid, a beta blocker and an angiotensin-converting enzyme inhibitor unless contraindicated. Left ventricular ejection fraction was determined at baseline and 4 months. Coronary angiography was repeated at 4 months. Baseline ejection fraction measured 20 +/- 12 days after myocardial infarction was 45 +/- 12% in both groups. PTCA was performed 21 +/- 13 days after the event. The primary PTCA success rate was 72%. One patient in each group died before angiographic follow-up, which was completed in 37 of the remaining 42 patients (88%; 21 with and 16 without PTCA). At 4 months, the infarct-related artery was patent in 43% of PTCA patients and in 19% of no PTCA patients (p = NS). Reocclusion occurred in 40% of patients after successful PTCA. Secondary analyses showed that the change in left ventricular ejection fraction was significantly greater in patients with a patent infarct-related artery (+9.4 +/- 6.2%) than in those with an occluded artery (+1.6 +/- 8.8%; p = 0.0096). Baseline ejection fraction also independently predicted improvement in left ventricular ejection fraction (p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
70.