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Rosa Raybaudi-Massilia Alexandra Zambrano-Durán Jonathan Mosqueda-Melgar María Isabel Calderón-Gabaldón 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2012,7(4):273-282
In this research, several plant compounds were in vitro evaluated against Salmonella enterica ser. Saintpaul and Escherichia coli O157:H7 through disc’s method. Among them Panax ginseng (PG) showed the highest antimicrobial activity in comparison to other natural antimicrobials. Combinations of PG (2?% v/v) with malic acid (MA) (0.5?% v/v) and/or potassium sorbate (PS) (0.05?% v/v) were made for evaluating their effects on S. Saintpaul and E. coli O157:H7 populations in sterile and fresh mango and orange juices stored at 5?°C. The best combination of antimicrobial compounds on native flora (during 21?days) as well as sensory attributes (0?day) of fresh juices were evaluated. The antimicrobial compounds added into mango and orange juices were more effective against S. Saintpaul than against E. coli O157:H7. The combination of PG (2?% v/v), MA (0.5?% v/v) and PS (0.05?% v/v) showed the highest antimicrobial effectiveness against both pathogenic microorganisms in both juices, in addition to a higher microbiological inhibition during storage (21?days). Sensory attributes such as aroma, color and taste were enhanced, but acidity was notably affected in both juices. In conclusion, the combination of PG, MA and PS could be an effective method in the food industry for ensuring the microbial safety and quality in mango and orange juices. 相似文献
84.
Jonathan Mosqueda-Melgar Rosa M. Raybaudi-Massilia Olga Martín-Belloso 《Food and Bioproducts Processing》2012,90(2):205-214
The effect of combining high-intensity pulsed electric fields (HIPEF) with citric acid or cinnamon bark oil, as antimicrobial substances, on the microbiological shelf life of strawberry, orange, apple, pear and tomato juices was evaluated in addition to the sensory properties of these products. An extension of the microbiological shelf life of fruit juices treated by HIPEF with or without antimicrobial substances was observed in comparison with those juices without processing. Naturally occurring microorganisms in the juices were inactivated by HIPEF treatment. Among the HIPEF treated juices, those from strawberry and orange did not show microbial growth along the 91 days of storage at 5 °C. However, resident microbial populations in apple, pear and tomato juices only were controlled during that time when HIPEF was combined with antimicrobials. Therefore, combinations of those treatments may be a feasible alternative to thermal pasteurization to ensure the microbiological quality and safety in juices, and to avoid the risk of foodborne illness caused by the consumption of these commodities. No significant changes on the sensory attributes in all studied fruit juices processed by HIPEF were found; but, when citric acid or cinnamon bark oil were added, noticeable changes on some sensory attributes such as aroma, taste and sourness of these fruit juices were perceived. 相似文献
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ABSTRACT: BACKGROUND: Food and nutritional care quality must be assessed and scored, so as to improve health institution efficacy. This study aimed to detect and compare actions related to food and nutritional care quality in public and private hospitals. METHODS: Investigation of the Hospital Food and Nutrition Service (HFNS) of 37 hospitals by means of structured interviews assessing two quality control corpora, namely nutritional care quality (NCQ) and hospital food service quality (FSQ). HFNS was also evaluated with respect to human resources per hospital bed and per produced meal. RESULTS: Comparison between public and private institutions revealed that there was a statistically significant difference between the number of hospital beds per HFNS staff member (p = 0.02) and per dietitian (p < 0.01). The mean compliance with NCQ criteria in public and private institutions was 51.8% and 41.6%, respectively. The percentage of public and private health institutions in conformity with FSQ criteria was 42.4% and 49.1%, respectively. Most of the actions comprising each corpus, NCQ and FSQ, varied considerably between the two types of institution. NCQ was positively influenced by hospital type (general) and presence of a clinical dietitian. FSQ was affected by institution size: large and medium-sized hospitals were significantly better than small ones. CONCLUSIONS: Food and nutritional care in hospital is still incipient, and actions concerning both nutritional care and food service take place on an irregular basis. It is clear that the design of food and nutritional care in hospital indicators is mandatory, and that guidelines for the development of actions as well as qualification and assessment of nutritional care are urgent. 相似文献
86.
Paula Rúbia Ferreira Rosa Samantha Christine Santos Edson Luiz Silva 《International Journal of Hydrogen Energy》2014
The fermentation of glucose, cheese whey and the mixture of glucose and cheese whey were evaluated in this study from two inocula sources (sludge from a UASB reactor for swine wastewater treatment and poultry slaughterhouse) for hydrogen production in continuous anaerobic fluidized bed reactors (AFBR). For all fermentations, a hydraulic retention time (HRT) of 6 h and a substrate concentration of 5 g COD L−1 were used. In glucose fermentation, the maximum hydrogen yield (HY) was 1.37 mmol H2 g−1 COD. The co-fermentation of the cheese whey and glucose mixture was favorable for the concomitant production of hydrogen and ethanol, with yields of up to 1.7 mmol H2 g−1 COD and 3.45 mol EtOH g−1 COD in AFBR2. The utilization of cheese whey as a sole substrate resulted in an HY of 1.9 mmol H2 g−1 COD. Throughout the study, ethanol fermentation was evident. 相似文献
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Ciro Vasmara Massimo Pindo Diego Micheletti Rosa Marchetti 《International Journal of Hydrogen Energy》2018,43(18):8707-8717
This study addresses for the first time the influence of initial pH on the evolution of microbial consortia in dark fermentation of scotta permeate, using a high-throughput sequencing approach. Three fermentation phases could be detected: 1) a lag phase with no substantial differences in microbial composition at different initial pH values; 2) an exponential H2 production phase, accompanied by a general increase of Clostridium genus components and higher incidence of Trichococcus genus at neutral and alkaline pH; 3) a final stationary phase, characterized by a general increase of Bifidobacterium and Lactobacillus genera in all reactors. The initial pH value influenced the relative abundance of Trichococcus at 16–48 h of incubation. The metabolic activity of this genus increased the amount of metabolic precursors of H2 so that, when pH lowered to 5.4, clostridia in the reactors with initial alkaline pH become more active H2-producers than those in the others. 相似文献
90.
Rafaela da Rosa Cardoso Edson Pinheiro de Lima Sergio E. Gouvea da Costa 《Journal of Manufacturing Systems》2012
AMT selection and adoption processes have been extensively studied. Topics that include financial and human factors, productivity, and coordination of the AMT implementation establish a substantial content of the present research agenda. The purpose of this paper is to study the organizational factors that influence the AMT implementation, considering a manufacturing strategy context and an analysis based on an organizational design framework. The research strategy is based on ‘empirical iterations’ using survey secondary data, experts’ interviews information and multiple case studies. The results show that there is a set of recommendations, which strongly influence the AMT implementation. Companies require a structured and integrative approach for the AMT implementation in order to take advantage of all their individual and systemic benefits. The set of proposed AMT recommendations for integrating these technologies to the organizational design are framed by structural, process and contextual aspects. 相似文献