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101.
The complexity of a social group may influence the vocal behavior of group members. Recent evidence in Carolina chickadees, Poecile carolinensis, indicated that one component of social complexity, group size, influenced the complexity of the "chick-a-dee" call, a vocalization functioning in social cohesion. Individuals in larger social groups used calls with greater information than did individuals in smaller social groups. Here, the authors review this earlier work, and describe a recent study indicating that social interactions between females and males within female-male pairs of chickadees were associated with rates of chick-a-dee call production in the males. Together, these studies suggest that the nature and complexity of social interactions among members of chickadee social groups influence chick-a-dee calling behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Loraine Van Der Colff Ellen Podivinsky 《International Journal of Food Science & Technology》2008,43(12):2105-2112
The ability to detect GM material in otherwise unprocessed foods cooked using domestic methods is important should ‘ready‐to‐eat’ foods require labelling. This study addresses the issue of DNA degradation in foods as a result of cooking. A number of ‘domestic’ cooking methods were shown to affect the length of DNA sequences able to be PCR amplified from potato samples and the degree of degradation was treatment‐specific. However, a. real‐time PCR assay was developed and. GM material was positively identified in all cooked GM potato samples. This confirms that GM material should be able to be detected in otherwise unprocessed food samples cooked using domestic methods, even if the cooking process has partially degraded the DNA. Results indicate, however, that there may be implications of the cooking process on the ability to accurately quantify GM content in some cooked samples. 相似文献
103.
Janneke de Jonge Hans van Trijp Ellen Goddard Lynn Frewer 《Food quality and preference》2008,19(5):439-451
A thorough understanding of consumer confidence in the safety of food and the factors by which this is influenced is necessary for the development of adequate and effective risk management and communication regarding food safety issues. As food chains become globalized, risk management and communication are increasingly applied at international levels. As a consequence, cross-culturally valid theoretical models are needed to investigate consumer confidence in the safety of food. In this study, consumer confidence in the safety of food in Canada and the Netherlands was systematically compared. On the basis of two nationally representative samples, it was examined to what extent differences in consumer confidence between the two countries resulted from differences in the relative importance of the determinants of confidence, and differences in the means of the constructs. No differences between Canada and the Netherlands were found regarding the relative importance of the determinants, which provides support for the generalizability of the framework. However, results indicated that Dutch consumers had a higher level of optimism and a lower level of pessimism regarding the safety of food, which appeared to be mainly related to Dutch consumers’ lower level of concern about factors related to production. The results also indicated cross-national differences in consumer recall of food safety issues in the media. 相似文献
104.
Silver Ellen J.; Bauman Laurie J.; Coupey Susan M.; Doctors Shelley R.; Boeck Marjorie A. 《Canadian Metallurgical Quarterly》1990,59(2):305
To examine the effects of chronic illness on the psychological growth process known as ego development, scores were compared on the Sentence Completion Test for 36 teens (16 boys, 20 girls) with chronic illness and 50 teens (16 boys, 34 girls) without chronic illness. Their ages ranged from 13 to 21 years, with a mean of 17.4 years. Most were Black (37%) or Hispanic (41%) and lived in poor or working-class neighborhoods. When age, sex, and Peabody Picture Vocabulary Test (PPVT) scores were controlled in multiple regression analyses, no direct association between ego development stage and presence of chronic illness, severity of illness, age at onset, or duration of illness was found. Analysis of the chronically ill group alone revealed a significant PPVT?×?Severity interaction, indicating that ego development in chronically ill teens is lower when illness is more severe and verbal IQ is higher. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
The durability of a commercially available injection molding grade polylactide (PLA) was assessed by exposure to conditions of elevated temperature and humidity over a period of several weeks. Moisture absorption, molecular weight, and mechanical performance were monitored over time and as a function of crystallinity level. At 50°C and 90% relative humidity, both amorphous and crystalline samples of PLA showed significant moisture absorption, allowing hydrolysis to occur. The study showed that while crystalline content had an effect on the initial moisture absorption behavior, the overall longer term effects on degradation were surprisingly minor. A cumulative damage model was used to relate the overall degradation due to moisture uptake and hydrolysis to long‐term durability in environments typical of automotive interiors. The study showed that the injection molding grade PLA resins that are currently commercially available are not suitable for use in applications that require long‐term durability in environments subject to elevated temperature and humidity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
106.
Teresa Wood Mary Ellen Wewers Judith Groner Karen Ahijevych 《Nicotine & tobacco research》2004,6(5):853-862
Adolescent smoking prevalence is a major health concern, with 24.4% reporting smoking in the past 30 days and 15.8% considered daily smokers. The purpose of this study was to characterize biobehavioral nicotine dependence, smoke constituent exposure and smoking topography in adolescent daily smokers. Relationships among biological markers of nicotine dependence (nicotine boost, carbon monoxide [CO] boost and cotinine levels) with existing self-report measures (modified Fagerstr?m Tolerance Questionnaire [mFTQ] and the motivations for smoking scale) were examined. Gender differences were characterized. Fifty adolescents 13-18 years old were recruited for the study, 50% female. CO, plasma nicotine levels pre- and postcigarette, cotinine, and smoking topography were measured during a smoking bout with participant's usual cigarette. Average CO boost, pre- to postcigarette was 7.2 + 3.6 ppm, baseline cotinine level averaged 224.0 +/- 169.6 ng/ml and nicotine boost averaged 23.4 +/- 21.7 ng/ml. Mean puffs per cigarette was 14.2 +/- 6.3. Males had significantly higher total puff volumes, but similar smoke constituent exposure to females, and higher handling of cigarettes as smoking motive. In regression analysis, 35% of variance in tobacco use, as indicated by baseline cotinine concentration, was explained by maximum puff duration, postcigarette CO level, and nicotine dependence, as measured by the mFTQ. Results indicated adolescents had considerable smoke constituent exposure and nicotine dependence suggesting the importance of appropriate smoking cessation treatment. 相似文献
107.
Abstract: Smoked salmon (Salmo salar L.) processing may generate large amounts of small pieces of trimmed flesh that has little economic value. Opportunities exist to develop new added‐value foods from this by‐product. Brining was compared with dry salting for the production of formed salmon jerky‐style strips that were then smoked. The formulations also contained brown sugar and potato starch. Salted samples had higher salt concentrations and required less force to break using a TA‐XT2 Texture Analyzer. Brined samples contained more fat and were darker, redder and more yellow than the salted samples. Processing concentrated omega‐3 fatty acids compared with raw salmon, and the brined jerky had the highest omega‐3 fatty acid content. A panel of 57 consumers liked the appearance and aroma of both samples equally (approximately 6.7 for appearance and 6.3 for aroma on the 9‐point hedonic scale. Higher acceptability scores for taste, texture, and overall quality were given to the brined product (6.7 to 6.9 against 6.2 to 6.3). Practical Application: Salmon trim from smoking facilities can be utilized to produce a jerky that is a good source of omega‐3 fatty acids, simultaneously adding value and reducing the waste stream. 相似文献
108.
Application of proteomics to understand the molecular mechanisms behind meat quality 总被引:1,自引:0,他引:1
The proteome is expressed from the genome, influenced by environmental and processing conditions, and can be seen as the molecular link between the genome and the functional quality characteristics of the meat. In contrast to traditional biochemical methods where one protein is studied at a time, several hundred proteins can be studied simultaneously. Proteomics is a promising and powerful tool in meat science and this is reflected by the increasing number of studies emerging in the literature using proteomics as the key tool to unleash the molecular mechanisms behind different genetic backgrounds or processing techniques of meat. Thus understanding the variations and different components of the proteome with regard to a certain meat quality or process parameter will lead to knowledge that can be used in optimising the conversion of muscles to meat. At present, there has been focus on development of techniques and mapping of proteomes according to genotypes and muscle types. In the future, focus should be more towards understanding and finding markers for meat quality traits. This review will focus on the methods used in the published proteome analyses of meat, with emphasis on the challenges related to statistical analysis of proteome data, and on the different topics of meat science that are investigated. 相似文献
109.
Rintala Diana H.; Young Mary Ellen; Hart Karen A.; Fuhrer Marcus J. 《Canadian Metallurgical Quarterly》1994,39(1):15
140 adults (aged 19–77 yrs) were randomly selected from a sampling frame of 661 persons with spinal cord injury. They completed a questionnaire assessing amount of social support, degree of reciprocity with supporters, and satisfaction with relationships with supporters; the Center for Epidemiologic Studies Depression Scale; a self-report version of the Functional Independence Measure; and the Craig Handicap Assessment and Reporting Technique. A physician assessed the degree of paralytic impairment by means of the ASIA Total Motor Index Score. Relationships in which the supporter gave more than the participant were associated with more satisfaction with the relationship and more social support. The number of reciprocal relationships was positively associated with more desirable outcomes in the handicap dimensions of mobility, occupation, social integration, and economic self-sufficiency. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
The influence of Arnheim's work on the author's research began with an experiment on the perception of visual balance. Two later research projects emerged from the profound influence of Arnheim's stance toward creation in the visual arts as a serious, cognitive endeavor. A series of meta-analyses were first conducted to test the claim that learning in the arts transfers to nonarts cognitive domains, but little evidence was found. Past research on the transfer hypothesis was found to be lacking because of its failure to assess learning in the parent domain. Therefore, a new research project was carried out to identify kinds of learning in the parent domain of visual arts. We identified eight thinking dispositions developed in serious visual arts classes, setting the stage for more plausible transfer studies. This study demonstrates that the visual arts inculcate basic skills in perception and cognition that exist both in the arts and sciences. All of the skills the authors describe can, with some modification, be transferred to the science laboratory. As Rudolf Arnheim has taught us, visual thinking is everywhere. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献