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排序方式: 共有773条查询结果,搜索用时 46 毫秒
31.
Dr. Jakob Franke Dr. Jeongwoon Kim John P. Hamilton Dr. Dongyan Zhao Gina M. Pham Krystle Wiegert-Rininger Emily Crisovan Linsey Newton Brieanne Vaillancourt Dr. Evangelos Tatsis Prof. Dr. C. Robin Buell Prof. Dr. Sarah E. O'Connor 《Chembiochem : a European journal of chemical biology》2019,20(1):83-87
Genome mining is a routine technique in microbes for discovering biosynthetic pathways. In plants, however, genomic information is not commonly used to identify novel biosynthesis genes. Here, we present the genome of the medicinal plant and oxindole monoterpene indole alkaloid (MIA) producer Gelsemium sempervirens (Gelsemiaceae). A gene cluster from Catharanthus roseus, which is utilized at least six enzymatic steps downstream from the last common intermediate shared between the two plant alkaloid types, is found in G. sempervirens, although the corresponding enzymes act on entirely different substrates. This study provides insights into the common genomic context of MIA pathways and is an important milestone in the further elucidation of the Gelsemium oxindole alkaloid pathway. 相似文献
32.
Ana C. LorenaAuthor Vitae Ivan G. CostaAuthor Vitae Newton SpolaôrAuthor Vitae 《Neurocomputing》2012,75(1):33-42
Currently, cancer diagnosis at a molecular level has been made possible through the analysis of gene expression data. More specifically, one usually uses machine learning (ML) techniques to build, from cancer gene expression data, automatic diagnosis models (classifiers). Cancer gene expression data often present some characteristics that can have a negative impact in the generalization ability of the classifiers generated. Some of these properties are data sparsity and an unbalanced class distribution. We investigate the results of a set of indices able to extract the intrinsic complexity information from the data. Such measures can be used to analyze, among other things, which particular characteristics of cancer gene expression data mostly impact the prediction ability of support vector machine classifiers. In this context, we also show that, by applying a proper feature selection procedure to the data, one can reduce the influence of those characteristics in the error rates of the classifiers induced. 相似文献
33.
34.
Tom F. OCallaghan David T. Mannion Deirdre Hennessy Stephen McAuliffe Maurice G. OSullivan Natasha Leeuwendaal Tom P. Beresford Pat Dillon Kieran N. Kilcawley Jeremiah J. Sheehan R. Paul Ross Catherine Stanton 《Journal of dairy science》2017,100(8):6053-6073
The purpose of this study was to investigate the effects of pasture-based versus indoor total mixed ration (TMR) feeding systems on the chemical composition, quality characteristics, and sensory properties of full-fat Cheddar cheeses. Fifty-four multiparous and primiparous Friesian cows were divided into 3 groups (n = 18) for an entire lactation. Group 1 was housed indoors and fed a TMR diet of grass silage, maize silage, and concentrates; group 2 was maintained outdoors on perennial ryegrass only pasture (GRS); and group 3 was maintained outdoors on perennial ryegrass/white clover pasture (CLV). Full-fat Cheddar cheeses were manufactured in triplicate at pilot scale from each feeding system in September 2015 and were examined over a 270-d ripening period at 8°C. Pasture-derived feeding systems were shown to produce Cheddar cheeses yellower in color than that of TMR, which was positively correlated with increased cheese β-carotene content. Feeding system had a significant effect on the fatty acid composition of the cheeses. The nutritional composition of Cheddar cheese was improved through pasture-based feeding systems, with significantly lower thrombogenicity index scores and a greater than 2-fold increase in the concentration of vaccenic acid and the bioactive conjugated linoleic acid C18:2 cis-9,trans-11, whereas TMR-derived cheeses had significantly higher palmitic acid content. Fatty acid profiling of cheeses coupled with multivariate analysis showed clear separation of Cheddar cheeses derived from pasture-based diets (GRS or CLV) from that of a TMR system. Such alterations in the fatty acid profile resulted in pasture-derived cheeses having reduced hardness scores at room temperature. Feeding system and ripening time had a significant effect on the volatile profile of the Cheddar cheeses. Pasture-derived Cheddar cheeses had significantly higher concentrations of the hydrocarbon toluene, whereas TMR-derived cheese had significantly higher concentration of 2,3-butanediol. Ripening period resulted in significant alterations to cheese volatile profiles, with increases in acid-, alcohol-, aldehyde-, ester-, and terpene-based volatile compounds. This study has demonstrated the benefits of pasture-derived feeding systems for production of Cheddar cheeses with enhanced nutritional and rheological quality compared with a TMR feeding system. 相似文献
35.
Disabled people want to have the same opportunities and experiences as everyone else, yet owing to a number of barriers they are often excluded from meaningful employment. There are few statistics available in the UK to provide an accurate understanding of the number of disabled people within construction, and there remains a lack of research on employment, disability and construction. The perceptions of, and barriers faced by, young disabled people in considering potential employment in the construction industry were investigated. A participatory research approach was adopted which places disabled people at the heart of the research process. A mix of interviews and mini focus groups was undertaken with a total of 49 participants drawn from the North West of England. The need for inclusive approaches within the construction industry came across strongly, with participants preferring to be treated equally rather than being treated favourably. Disabled young people are unlikely to consider employment within construction without better awareness raising by industry–both employers and professional institutions–of the range and scope of opportunities available, and a dispelling of the myths that construction is for able-bodied, fit, men. 相似文献
36.
Gano-Overway Lori A.; Newton Maria; Magyar T. Michelle; Fry Mary D.; Kim Mi-Sook; Guivernau Marta R. 《Canadian Metallurgical Quarterly》2009,45(2):329
Understanding what factors influence positive youth development has been advocated by youth development researchers (P. L. Benson, 2006; J. S. Eccles & J. A. Gootman, 2002). Consequently, the purpose of this study was to examine whether perceptions of a caring youth sport context influenced prosocial and antisocial behavior through efficacy-related beliefs, that is, positive and negative affective self-regulatory efficacy (ASRE) and empathic self-efficacy (ESE). Multiethnic youths taking part in summer sport programs (N = 395) completed a questionnaire that measured perceptions of the caring climate, ESE, ASRE, and social behavior. Structural equation modeling was used to test whether ASRE and ESE mediated the relationship between caring and social behaviors. Findings revealed that perceptions of caring positively predicted ASRE and ESE. In turn, positive ASRE positively predicted ESE. Prosocial behaviors were positively linked to ESE, whereas antisocial behaviors were negatively predicted by positive ASRE. The results suggest that caring influences prosocial and antisocial behavior because such contexts develop youths' ability to monitor, manage, and control positive affect, which in turn enhances their belief in their ability to empathize. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
Newton K. Amaglo Richard N. Bennett Rosario B. Lo Curto Eduardo A.S. Rosa Vincenzo Lo Turco Angela Giuffrida Alberto Lo Curto Francesco Crea Gladys M. Timpo 《Food chemistry》2010
The purpose of this new study was to determine the types and levels of major phytochemicals (non-nutrients) and nutrients in the different tissues from vegetative and flowering Moringa oleifera L. an important multipurpose crop. Rhamnose and acetyl-rhamnose-substituted glucosinolates were found in all of the M. oleifera tissues with different profiles depending on the tissue. In addition the tissues of M. oleifera had a relatively complex flavonoid profile consisting of glucosides, rutinosides, malonylglucosides and traces of acetylglucosides of kaempferol, quercetin and isorhamnetin. Fatty acid profiling of the different tissues showed that leaves were rich in palmitic (16:0) and linolenic (18:3) acid whereas seeds were predominated by oleic acid (18:1). Roots were rich in palmitic and oleic acid, whereas stems and twigs predominately contained palmitic acid. Potassium, magnesium and calcium were the predominant minerals in all of the tissues. Low levels of selenium were detected only in whole seeds. 相似文献
38.
Susane Moreira Machado Anderson Oliveira Lobo Ariel Bueno Loureiro Sapucahy Fernanda Roberta Marciano Evaldo Jose Corat Newton Soares da Silva 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1614-1617
For the first time, we show that Tritrichomonas foetus can adhere on superhydrophilic vertically aligned carbon nanotubes (VACNT) films. Scanning electron microscopy shows an unusual adhesion with a higher membrane filopodium projection in all directions, directly attached to superhydrophilic VACNT tips. 相似文献
39.
The transport of positively charged redox active species through spiropyran-modified nanopores in silica colloidal films was
controlled using light. The silica colloidal films were comprised of 18 layers of face centered cubic (fcc)-packed 170 nm
silica spheres. The surface of the films was first modified with amines, which were then used to attach the spiropyran moiety
to the surface. The limiting current of a positively charged redox active species through the spiropyran-modified nanopore
decreased after irradiation with UV light at pH 6.6. When the silica colloidal film was subsequently irradiated with visible
light the initial limiting current was restored. 相似文献
40.
P.W. Newton 《Urban Policy and Research》2013,31(4):227-229
Changes over the past twenty-five years in information and communication technology (ICT) are beginning to provide us with a clearer picture of the technical platform that will influence the shape of urban and industrial development into the 21st century. During this period we have experienced a number of key paradigm shifts in computing: from 1960s batch systems to 1970s time sharing systems to 1980s desktop systems (Newton et al. 1988). At the same time, but somewhat independently, communications were evolving from the slow speed analogue public switched telephone network which provided a measure of computer-to-computer interaction (via modems) to the newly emerging high speed broadband digital networks, networks which will provide a truly vast array of value added products and services (discussed more fully in Cavill and Fidler' paper). The dramatic price-performance improvements in these technologies and the synergy which now exists between computers and communications provides us in the 1990s with the core information infrastructure of the future: computers and the networks that interconnect them (Newton etal. 1991). 相似文献