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61.
Yung-Sheng Huang Dave E. Mills Ron P. Ward David F. Horrobin Valerie A. Simmons 《Lipids》1989,24(7):565-571
Weanling male spontaneously hypertensive (SHR) and normotensive (WKY) rats were maintained on a fat-free semisynthetic diet
and killed at various intervals. The effects of fat-depletion on the appearance of essential fatty acid (EFA) deficiency symptoms,
the progressive changes of major fatty acids in plasma, liver, heart, and kidney phospholipids (PL), and in skin total lipids
were compared between these two strains. After five weeks on the diet, the slower growth and the appearance of EFA deficiency
symptoms became evident in SHR. In general, fat-depletion reduced the levels of n−6 fatty acids, whereas it increased those
of 20∶3n−9. However, the fat-depletion induced reduction of 18∶2n−6 in heart PL and 20∶4n−6 in kidney, while the elevation
of 20∶3n−9 in plasma, heart, and kidney PL were greater in WKY than in SHR. As a result, the elevation of biochemical EFA
deficiency index—20∶3n−9/20∶4n−6 ratio—was greater in WKY than in SHR. In comparison with WKY, the concentrations of liver
triacylglycerols and the weights of adipose tissues in SHR were reduced to a greater extent, indicating an active catabolism
of triacylglycerols in SHR. This study suggests that the earlier appearance of morphological symptoms of EFA deficiency in
SHR was not associated with the reducing n−6 EFA levels or with an elevation of triene/tetraene ratio, but possibly to a reduced
supply of n−6 EFA for skin prostaglandin synthesis. 相似文献
62.
Microbial hazards related to rice sprouting 总被引:3,自引:0,他引:3
Valerie Piernas & Joseph P. Guiraud 《International Journal of Food Science & Technology》1997,32(1):33-39
The microbiology of rice seeds selected for commercial production of sprouts was studied. Bacteria were numerous but generally nonpathogenic: almost all were gram-negative rods, predominantly pseudomonads. There were also several enterobacteria, in particular Enterobacter and Klebsiella species. Escherichia coli was present in very few samples and its serotype was not enteropathogenic. Moulds were infrequent. Storage of seeds under laboratory conditions did not greatly modify the composition of the microflora but counts decreased with time. When grains were stored in a cold room, the microflora remained almost unchanged quantitatively and qualitatively. After 2 days of germination, mesophilic aerobic plate counts increased by about 2 log cycles; thermotolerant coliforms and faecal enterococci increased by up to 6 log cycles. No foodborne pathogens were detected on sprouts. Moreover, both dry seeds and sprouts were negative for aflatoxins. Experiments with artificially inoculated seeds showed that Bacillus cereus and Listeria sp. could develop without any antagonistic effect from the background flora of germinating rice. 相似文献
63.
Valerie M. Muller Rita V. Burke Helen Arbogast Perla C. Ruiz Nellie M. Nunez Katherine R. San Mateo Francesca Cazzulino Jeffrey S. Upperman 《Accident; analysis and prevention》2014
Background
Child passenger restraint systems have been found to greatly reduce the risk of injury and death among child passengers. However, nearly half of the children who died in 2009 as a result of motor vehicle crashes were completely unrestrained. Our global hypothesis is that parents and other caregivers failed to restrain children due to a lack of child passenger seat education and practice. In this report, we postulate that a car seat class will improve the basic understanding of child passenger safety. The objective of the study was to evaluate the effectiveness of a car seat class in increasing parental knowledge about child passenger safety.Methods
Car seat classes were held at a Level 1 pediatric trauma center every other Tuesday for ten months. The curriculum consisted of: child passenger safety laws discussion, a 21-min video on the use of child safety seats followed by a 15-min discussion about the video, 15 min of discussing the different types of car seats, and hands-on training on how to properly install and use child restraints. Free car seats were provided to eligible parents. The pre-test was administered at the beginning of class and the post-test at the end of the class. McNemar's test and a paired t-test were used to compare pre- and post-test scores. Test scores were also stratified by language spoken.Results
Forty-four classes were held and a total of 491 parents/caregivers attended the classes. An increase in knowledge was found for all survey questions. Mean knowledge score for the post-test was 3.10 points higher compared to the mean knowledge score from the pre-test. Mean difference in knowledge scores for English-speaking participants were higher than Spanish-speaking participants.Conclusion
Lack of knowledge and low risk perception have frequently been cited as barriers for the use of child passenger restraints. Our intervention attempted to eliminate these barriers. We found that this intervention was effective at increasing parental knowledge about child passenger safety. The results of this study may be used to design and implement future interventions in multicultural settings. 相似文献64.
65.
66.
A study of misorientation distributions in recrystallised high-strength IF steel has compared both the disorientation (lowest angle) solution and nearest low-index axis solution. It is shown that consideration of the lowest-angle misorientation distribution alone provides an incomplete and ambiguous distribution of nearest low-index misorientation axes. 相似文献
67.
68.
Manitoba's Rural and Northern Community-Based Training Program for Psychology Interns and Residents.
McIlwraith Robert D.; Dyck Karen G.; Holms Valerie L.; Carlson Torie E.; Prober Nancy G. 《Canadian Metallurgical Quarterly》2005,36(2):164
This article describes a unique internship training experience developed by the Department of Clinical Health Psychology of the Faculty of Medicine of the University of Manitoba. Interns live in and provide services to remote northern communities for half of the internship year and receive supervision from a psychologist in the community, supplemented by telehealth. The department also offers a full-year, postdoctoral rural residency. Ten interns and 4 residents have been trained so far. The community-based generalist training model and responses to the challenges, for both supervisors and trainees, of working in small underserved communities are described. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Werker Janet F.; Cohen Leslie B.; Lloyd Valerie L.; Casasola Marianella; Stager Christine L. 《Canadian Metallurgical Quarterly》1998,34(6):1289
The following experiments were designed to determine the age at which infants can first readily learn word–object pairings with only minimal exposure and without social or contextual support. To address this question, 8- to 14-month-old infants were tested on their ability to form word–object associations in a "switch" design. Infants were habituated to 2 word–object pairings and then tested with 1 trial that maintained a familiar word–object pairing and 1 that involved a familiar word and object in a new combination. Across 6 experiments, only 14-month-old infants formed word–object associations under these controlled testing conditions but appeared to do so only when the objects were moving. Although 8- to 12-month-olds did not form the associations, they appeared to process both the word and the object information. These studies provide strong evidence that 14-month-old infants can rapidly learn arbitrary associations between words and objects, that this ability appears to develop at about 14 months of age, and that the Switch design is a useful method for assessing word–object learning in infancy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Valerie Barr 《Annals of Software Engineering》1997,4(1):171-189
In this paper we discuss ways in which coverage analysis, obtained during execution of test cases over a rule‐base, can be
used to highlight problems in both the test suite and the rule‐base, thereby pointing to areas in which we cannot guarantee
or predict the system’s performance. In particular, we present a series of heuristics which use coverage information and meta‐knowledge
about the larger population to select additional test cases from the population, in the event that the initial test set is
incomplete. This forms the basis of an incremental approach to rule‐base testing which allows us to both increase completeness
of the test set and improve coverage of the rule‐base, thereby increasing the kinds of cases for which the rule‐base has been
executed during testing. We demonstrate this heuristic approach to test data selection using information generated by TRUBAC,
a tool which implements the coverage analysis methods, applied to analyze a prototype system for diagnosis of rheumatological
diseases. 相似文献