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1.
Projects are inherently uncertain and face unexpected events, from small changes in scope to unforeseen client’s bankruptcy. This paper studies how project managers respond to such events and how successful and unsuccessful responses differ from the perspective of the practitioner. We analysed 44 unexpected events faced by 22 experienced project managers in defence and defence-related organisations. The project managers compared two unexpected events that they faced, one that they considered the response successful and the other unsuccessful. We identified three pillars supporting successful responses to unexpected events: (1) responsive and functioning structure at the organisational level, (2) good interpersonal relationship at the group level and (3) competent people at the individual level. The events and respective responses analysed suggest that improvement in project management can be achieved by better managing these three pillars, allowing project and programme managers to “create their own luck”. 相似文献
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Joana T. Martins Ana I. Bourbon Ana C. Pinheiro Bartolomeu W. S. Souza Miguel A. Cerqueira António A. Vicente 《Food and Bioprocess Technology》2013,6(8):2081-2092
The aims of this work were to evaluate the physical and antimicrobial properties of biodegradable films composed of mixtures of κ-carrageenan (κ-car) and locust bean gum (LBG) when organically modified clay Cloisite 30B (C30B) was dispersed in the biopolymer matrix. Film-forming solutions were prepared by adding C30B (ranging from 0 to 16 wt.%) into the κ-car/LBG solution (40/60 wt.%) with 0.3 % (w/v) of glycerol. Barrier properties (water vapour permeability, P vapour; CO2 and O2 permeabilities), mechanical properties (tensile strength, TS, and elongation-at-break, EB) and thermal stability of the resulting films were determined and related with the incorporation of C30B. Also, X-ray diffraction (XRD) was done in order to investigate the effect of C30B in film structure. Antimicrobial effects of these films against Listeria monocytogenes, Escherichia coli and Salmonella enterica were also evaluated. The increase of clay concentration causes a decrease of P vapour (from 5.34?×?10?11 to 3.19?×?10?11 g (m s?Pa)?1) and an increase of the CO2 permeability (from 2.26?×?10?14 to 2.91?×?10?14 g (m s?Pa)?1) and did not changed significantly the O2 permeability for films with 0 and 16 wt.% C30B, respectively. Films with 16 wt.% clay exhibited the highest values of TS (33.82 MPa) and EB (29.82 %). XRD patterns of the films indicated that a degree of exfoliation is attained depending on clay concentration. κ-car/LBG–C30B films exhibited an inhibitory effect only against L. monocytogenes. κ-car/LBG–C30B composite films are a promising alternative to synthetic films in order to improve the shelf life and safety of food products. 相似文献
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A SYBR Green real-time PCR assay to detect and quantify pork meat in processed poultry meat products 总被引:3,自引:0,他引:3
Species identification in meat products has grown in interest in recent years since these foodstuffs are susceptible targets for fraudulent labelling. In this work, a real-time PCR approach based on SYBR Green dye was proposed for the quantitative detection of pork meat in processed meat products. For the development of the method, binary meat mixtures containing known amounts of pork meat in poultry meat were used to obtain a normalised calibration model from 0.1 to 25% with high linear correlation and PCR efficiency. The method revealed high specificity by melting curve analysis, being successfully validated through its application to blind meat mixtures, which confirmed its adequacy for pork meat determination. The fully applicability of the method was further demonstrated in commercial meat products, allowing verification of labelling compliance and identification of meat species in processed foods. 相似文献
6.
Joana Oliveira Jennifer Mahony Laurens Hanemaaijer Thijs R.H.M. Kouwen Douwe van Sinderen 《Journal of dairy science》2018,101(1):96-105
In the current study, we characterized 137 Lactococcus lactis bacteriophages that had been isolated between 1997 and 2012 from whey samples obtained from industrial facilities located in 16 countries. Multiplex PCR grouping of these 137 phage isolates revealed that the majority (61.31%) belonged to the 936 group, with the remainder belonging to the P335 and c2 groups (23.36 and 15.33%, respectively). Restriction profile analysis of phage genomic DNA indicated a high degree of genetic diversity within this phage collection. Furthermore, based on a host-range survey of the phage collection using 113 dairy starter strains, we showed that the c2-group isolates exhibited a broader host range than isolates of the 936 and P335 groups. 相似文献
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Desirrê Morais Dias Neuza Maria Brunoro Costa Marilia Regini Nutti Elad Tako Hércia Stampini Duarte Martino 《Critical reviews in food science and nutrition》2018,58(13):2136-2146
ABSTRACTBiofortification aims to improve the micronutrient concentration of staple food crops through the best practices of breeding and modern biotechnology. However, increased zinc and iron concentrations in food crops may not always translate into proportional increases in absorbed zinc (Zn) and iron (Fe). Therefore, assessing iron and zinc bioavailability in biofortified crops is imperative to evaluate the efficacy of breeding programs. This review aimed to investigate the advantages and limitations of in vitro and in vivo methods of iron and zinc bioavailability evaluation in the assessment of biofortification program effectiveness. In vitro, animal and isotopic human studies have shown high iron and zinc bioavailability in biofortified staple food crops. Human studies provide direct knowledge regarding the effectiveness of biofortification, however, human studies are time consuming and are more expensive than in vitro and animal studies. Moreover, in vitro studies may be a useful preliminary screening method to identify promising plant cultivars, however, these studies cannot provide data that are directly applicable to humans. None of these methods provides complete information regarding mineral bioavailability, thus, a combination of these methods should be the most appropriate strategy to investigate the effectiveness of zinc and iron biofortification programs. 相似文献
8.
Joana Costa Isa Silva António A. Vicente 《Critical reviews in food science and nutrition》2019,59(4):546-562
Pistachio nut (Pistacia vera) is highly appreciated for its organoleptic characteristics and potential health benefits. However, this tree nut is also responsible for triggering moderate to severe IgE-mediated reactions in allergic individuals. Currently, pistachio nut allergy has gained some special attention, mainly due to its intrinsic relation with cashew nut allergy. Like for other nuts, the prevalence of pistachio nut allergy seems to be increasing at a global scale. Until now, there are five allergenic proteins officially listed for pistachio nut (Pis v 1, Pis v 2, Pis v 3, Pis v 4 and Pis v 5). Relevant data on their biochemical classification has become available, enabling establishing a correlation with the respective clinical symptoms. The establishment of an effective allergen risk assessment is a key issue for the food industry, policy makers and regulatory agencies. Thus, the availability of fast, specific and sensitive methods to detect trace amounts of allergens in processed foods is crucial. In the specific case of pistachio nut, there are some protein- and DNA-based methods for its detection/quantification in foods, which can aid to verify label information. Accordingly, all relevant research advances on this topic were summarised, updated and critically discussed in this review. 相似文献
9.
Nuno Mateus Joana Oliveira João Pissarra Ana M. González-Paramás Julian C. Rivas-Gonzalo Celestino Santos-Buelga Artur M.S. Silva Victor de Freitas 《Food chemistry》2006
A new pyranoanthocyanin–vinylphenol pigment was detected in an aged Port red wine. The UV–Vis spectrum of this pigment was found to have a λmax of 538 nm that is bathochromically shifted from that of original anthocyanins, exhibiting a more purple hue in acidic solution. This newly formed pigment was synthesized in model solution through the reaction between malvidin 3-O-glucoside–pyruvic acid adduct and vinylphenol and its structure was assigned by NMR and mass spectrometry. This pigment is reported herein for the first time. 相似文献
10.
E.N. Andrade A. Polizel Neto R.O. Roça M.H. Faria F.D. Resende G.R. Siqueira R.S.B. Pinheiro 《Meat science》2014
This work evaluated the beef quality parameters of 108 bulls randomly administered to three treatments during rearing in pastures and two treatments during fatting in feedlots, including mineral and rumen-protected lipids. Meat and fat color, cooking yield, shear force, sensorial traits and chemical and fatty acid compositions were evaluated. Generally, the beef quality parameters were not affected by the rumen protected lipids; however, supplementation with rumen-protected lipids during the rearing period yielded darker beef and brighter fat and increased beef tenderness in meat aged for 28 days compared to the meat from animals that received only mineral supplementation. In addition, the percent of meat polyunsaturated fatty acids was negatively affected by the inclusion of protected lipids, yielding 5.58 and 3.72% in animals fed with and without rumen-protected lipids, respectively, during the fatting period. 相似文献