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排序方式: 共有3632条查询结果,搜索用时 15 毫秒
71.
Copetti MV Iamanaka BT Mororó RC Pereira JL Frisvad JC Taniwaki MH 《International journal of food microbiology》2012,155(3):158-164
The acidic characteristics of cocoa beans have influence on flavor development in chocolate. Cocoa cotyledons are not naturally acidic, the acidity comes from organic acids produced by the fermentative microorganisms which grow during the processing of cocoa. Different concentrations of these metabolites can be produced according to the fermentation practices adopted in the farms, which could affect the growth and ochratoxin A production by fungi. This work presents two independent experiments carried out to investigate the effect of some fermentation practices on ochratoxin A production by Aspergillus carbonarius in cocoa, and the effect of weak organic acids such as acetic, lactic and citric at different pH values on growth and ochratoxin A production by A. carbonarius and Aspergillus niger in culture media. A statistical difference (ρ<0.05) in the ochratoxin A level in the cured cocoa beans was observed in some fermentation practices adopted. The laboratorial studies demonstrate the influence of organic acids on fungal growth and ochratoxin A production, with differences according to the media pH and the organic acid present. Acetic acid was the most inhibitory acid against A. carbonarius and A. niger. From the point of view of food safety, considering the amount of ochratoxin A produced, fermentation practices should be conducted towards the enhancement of acetic acid, although lactic and citric acids also have an important role in lowering the pH to improve the toxicity of acetic acid. 相似文献
72.
Supercritical fluid extraction of fish oil from fish by-products: A comparison with other extraction methods 总被引:4,自引:0,他引:4
Nuria Rubio-RodríguezSara M. de Diego Sagrario Beltrán Isabel JaimeMaría Teresa Sanz Jordi Rovira 《Journal of food engineering》2012,109(2):238-248
Fish and fish by-products are the main natural source of omega-3 polyunsaturated fatty acids, especially EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), both of them with a great importance in the food and pharmaceutical industries. Comparing to conventional fish oil extraction processes such as cold extraction, wet reduction or enzymatic extraction, supercritical fluid extraction with carbon dioxide under moderate conditions (25 MPa and 313 K) may be useful for reducing fish oil oxidation, especially when fish oil is rich in omega-3 such as salmon oil, and the amount of certain impurities, such as some species of arsenic. Furthermore, taking profit of the advantages of supercritical carbon dioxide as extractive solvent, a coupled extraction-fractionation process is proposed as a way to remove free fatty acids and improve fish oil quality, alternatively to physical and chemical refining procedures. 相似文献
73.
Morcilla de Burgos is the most famous blood sausage in Spain. However, while producers are interested in extending its shelf life, the consumer is increasingly demanding more natural food. This situation has led to the current search for new and mild preservation technologies. Two batches of four different products: control without any treatment, control with organic acid salts (CnOAS; a 3% mixture of potassium/sodium l-lactate), control with high hydrostatic pressure processing (CnHPP; 600MPa-10min), and a combination of both treatments (OAS+HPP), were carried out to evaluate any synergistic effect that occurs when combining OAS and HPP, and the influence of different preservative treatments on the spoilage bacterial population and their evolution. HPP (with or without addition of OAS) can be considered the most suitable method for preserving morcilla de Burgos as it does not produce negative changes in sensory attributes. No clear selective effect of different treatments on the composition of the spoilage bacteria was seen and similar spoilage patterns were observed independently of the preservation treatment used. 相似文献
74.
Maria Eliza de Castro Moreira Rosemary Gualberto Fonseca Alvarenga Pereira Danielle Ferreira Dias Vanessa Silva Gontijo Fabiana Cardoso Vilela Gabriel de Oliveira Isac de Moraes Alexandre Giusti-Paiva Marcelo Henrique dos Santos 《Journal of Functional Foods》2013,5(1):466-474
Green coffee contains a large quantity and variety of polyphenols and flavonoids. The roasting affects the composition of the polyphenols in coffee, due to the formation of compounds generated by Maillard reaction, which can have anti-inflammatory or antioxidant potential. The anti-inflammatory and antioxidant effects of aqueous extracts of green (AGCa) and roasted (ARCa) coffee beans were investigated in animal models and using a DPPH radical scavenging test. In the formalin test the extracts reduced licking activity only in the late phase. The inhibitory values of oedema at 3 h post-carrageenan were 53% and 74% for 100 and 300 mg/kg of the AGCa extract and 36% for ARCa (300 mg/kg). Leukocyte recruitment into the peritoneal cavity was inhibited by the extracts. The antioxidant activities of the extracts were higher than the reference antioxidants, ascorbic acid and butylated hydroxytoluene. These results indicate that coffee extracts exhibit anti-inflammatory and antioxidant properties. 相似文献
75.
Phenol‐enriched olive oils modify paraoxonase‐related variables: A randomized,crossover, controlled trial 下载免费PDF全文
76.
Eva Giralt-Steinhauer Joan Jimnez-Balado Isabel Fernndez-Prez Lucía Rey lvarez Ana Rodríguez-Campello ngel Ois Elisa Cuadrado-Godia Jordi Jimnez-Conde Jaume Roquer 《International journal of molecular sciences》2022,23(12)
Intracerebral hemorrhage (ICH) is a complex and heterogeneous disease, and there is no effective treatment. Spontaneous ICH represents the final manifestation of different types of cerebral small vessel disease, usually categorized as: lobar (mostly related to cerebral amyloid angiopathy) and nonlobar (hypertension-related vasculopathy) ICH. Accurate phenotyping aims to reflect these biological differences in the underlying mechanisms and has been demonstrated to be crucial to the success of genetic studies in this field. This review summarizes how current knowledge on genetics and epigenetics of this devastating stroke subtype are contributing to improve the understanding of ICH pathophysiology and their potential role in developing therapeutic strategies. 相似文献
77.
Ricardo Cambraia Parreira Diana Paola Gmez‐Mendoza Itamar Couto Guedes de Jesus Rafael Pereira Lemos Anderson Kennedy Santos Cristiana Perdigo Rezende Henrique Csar Pereira Figueiredo Mauro Cunha Xavier Pinto Frank Kjeldsen Silvia Guatimosim Rodrigo Ribeiro Resende Thiago Verano‐Braga 《Proteomics. Clinical applications》2020,14(4)
78.
This study investigated the short-term effects of daily recovery, that is, impaired psychological detachment from work and various actigraphical indicators of sleep quality, on near-accidents when commuting to work the next morning. Furthermore, the mediating effect of actigraphically assessed sleep quality on the relationship between impaired psychological detachment from work and near-accidents when commuting to work was analysed. Fifty-six full-time employees of a Swiss assurance company participated in the one-week study. Multilevel analyses revealed that impaired detachment was highly related to a decrease in sleep duration. Furthermore, impaired daily recovery processes, such as impaired psychological detachment from work and disturbed sleep quality, were related to commuting near-accidents. Impaired sleep quality mediated the effect of impaired psychological detachment from work on these near-accidents. Our results show that occupational safety interventions should address both impaired psychological detachment from work and sleep quality in order to prevent near accidents when commuting to work.
Practitioner Summary: Commuting accidents occur frequently and have detrimental effects on employees, organisations and society. This study shows that daily lack of recovery, that is, impaired psychological detachment and impaired sleep quality, is related to near-accidents when commuting to work the next morning. Primary prevention of commuting accidents should therefore address daily lack of recovery. 相似文献
79.
Jordi Mongay Batalla Constandinos X. Mavromoustakis George Mastorakis Daniel Négru Eugen Borcoci 《The Journal of supercomputing》2017,73(3):993-1016
Critical applications which need to deliver multimedia through the Internet, may achieve the required quality of service thanks to the Content-Aware Networks (CAN). The key element of CAN is an efficient decision algorithm responsible for the selection of the best content source and routing paths for content delivery. This paper proposes a two-phase decision algorithm, exploiting the Evolutionary Multiobjective Optimization (EMO) approach. It allows to consider valid information in different time scales, adapting decision-maker to the evolving network and server conditions as well as to get the optimal solution in different shapes of Pareto front. The simulation experiments performed in a large-scale network model, confirm the effectiveness of the proposed two-phase EMO algorithm, comparing to other multi-criteria decision algorithms used in CAN. 相似文献
80.
Karina T. Magalhães Giuliano Dragone Gilberto V. de Melo Pereira José M. Oliveira Lucília Domingues José A. Teixeira João B. Almeida e Silva Rosane F. Schwan 《Food chemistry》2011
Cheese whey (CW) and deproteinised cheese whey (DCW) were investigated for their suitability as novel substrates for the production of kefir-like beverages. Lactose consumption, ethanol production, as well as organic acids and volatile compounds formation, were determined during CW and DCW fermentation by kefir grains and compared with values obtained during the production of traditional milk kefir. The results showed that kefir grains were able to utilise lactose from CW and DCW and produce similar amounts of ethanol (7.8–8.3 g/l), lactic acid (5.0 g/l) and acetic acid (0.7 g/l) to those obtained during milk fermentation. In addition, the concentration of higher alcohols (2-methyl-1-butanol, 3-methyl-1-butanol, 1-hexanol, 2-methyl-1-propanol, and 1-propanol), ester (ethyl acetate) and aldehyde (acetaldehyde) in cheese whey-based kefir and milk kefir beverages were also produced in similar amounts. Cheese whey and deproteinised cheese whey may therefore serve as substrates for the production of kefir-like beverages similar to milk kefir. 相似文献