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61.
Traditional methods of economic analysis to justify equipment selection and use are based on several methods such as the Net Present Value, Break-Even Analysis, Pay-Back Period, Return on Investment, among others. However, with the introduction of automation, Flexible Manufacturing Systems (FMS), and Computer Integrated Manufacturing Systems (CIMS), such economic analyses have often resulted in decisions that management did not like to support but did not have much choice to avoid on account of pressure from manufacturing engineers, design engineers and others in the operations areas. The real problem of equipment selection and justification lies in the methodologies used.

This paper presents a unique approach to equipment justification by applying Sumanth's TOTAL PRODUCTIVITY MODEL, whereby the anticipated impact of the proposed equipment on profitability is assessed from the point of total productivity and the five partial productivities. Then, only if the equipment increases the total productivity level beyond its break even point, the equipment is selected or justified.

This method offers a non-traditional approach to justifying and selecting equipment in all types of environment. A numerical example is presented by using LOTUS 1-2-3TM on an IBM PC. Advantages and limitations to this approach are discussed to provide a balanced perspective on the important issue of equipment selection and justification.  相似文献   

62.
Olive trees (Olea europaea L. Cv. Cobrançosa) from the northeast of Portugal were sprayed with three different copper formulations [bordeaux mixture (copper sulphate + calcium hydroxide − 20% Cu), copper hydroxide (40% Cu) and copper oxychloride (50% Cu)] to control olive fungal diseases. The residues of copper in olive leaves, harvested at different times, were evaluated by atomic absorption spectrometry. At all the collection times, treated olive leaves had significantly higher copper contents, compared to the control. The different copper amounts in pesticide formulations lowered the leaves contents in total phenols and hence their antioxidant properties. Olive leaves sprayed with copper oxychloride possessed the highest copper levels and the lowest content in phenols, which influenced its antioxidant activity (higher EC50 values for reducing power, scavenging effect on DPPH radicals and inhibition of erythrocyte hemolysis). Leaves without copper residues proved to be a good natural source of antioxidants, giving values comparable to the reference compounds.  相似文献   
63.
Flavonoids are a group of polyphenolic compounds with health-related properties. Citrus fruits are rich in flavonoids and their extracts are being used as functional ingredients for several industrial products. A new high performance liquid chromatography technique with an UV photodiode-array detector was used to analyze flavonoids of an extract of Citrus species. To our knowledge this is the first study that reports isoquercitrin presence at a level of 77.3 mg/100 g in a sample made of Citrus fruits; four other flavonoids were quantified as rutin (326.59 mg/100 g), naringin (338.36 mg/100 g), quercetin (96.35 mg/100 g) and naringenin (2.35 mg/100 g). Identification was confirmed by a liquid chromatography mass spectrometer system. Method validation was achieved, providing an analytical technique that can be used to detect trace amounts of these compounds in Citrus extracts with an extremely rapid sample preparation.  相似文献   
64.
In this paper, solar radiation obtained from different frequently used databases is compared in some different locations. In the analyzed databases, the data come from ground measurement networks, or from different models and with different resolutions. The proposed methodology assumes the hypothesis that the uncertainty of the databases is approximately the same as the meteorological uncertainty of the location. Therefore the heterogeneity of the observations is due to different observations. A weighted average is proposed taking into account different time and spatial characteristics of each database, and the estimation of standard deviation of weighted observations that derives the meteorological variability expected.  相似文献   
65.
Summary The mineral composition of 113 samples of ewes', cows', and goats' milk and 68 samples of different types of pure-milk cheeses made from the milks of these species was analysed. Stepwise discriminant analysis of the milk samples yielded the variables K/Mg, Na/Ca, Zn, Cu/Zn, and Cu/Na as the most useful in differentiating the samples, achieving correct classification in 98.2% of cases. The most useful variables for the cheese samples were Fe/K, Na/Ca, Zn/Cu, Na/Mg, and Zn, which yielded correct classification in 97.1% of cases. The three goat's milk cheeses were successfully distinguished using the variables K/Zn, Fe/Cu, and P.
Unterscheidung zwischen verschiedenen Milch- und Käsesorten anhand ihrer Mineralstoff-Zusammensetzung
Zusammenfassung An 113 Milchproben und 68 mit Schafmilch, Kuhmilch und Ziegenmilch hergestellten Käseproben wurde die Mineralstoff-Zusammensetzung analysiert. Die Anwendung der schrittweisen Diskriminatoriusanalyse bei den Milchproben ergab die Auswahl der Veränderlichen K/Mg, Na/Ca, Zn, Cu/Zn und Cu/Na als beste Unterschiedlichkeitsparameter mit einer zu 98,2% einwandfreien Klassifizierung. Die bei Käse ausgewählten Veränderlichen waren Fe/K, Na/Ca, Zn/Cu, Na/Mg und Zn mit einer zu 97,1% einwandfreien Klassifizierung. Die Unterscheidung zwischen den 3 geprüften Ziegenmilch-Käsesorten wurde durch die Veränderlichen K/Zn, Fe/Cu und P ermöglicht.
  相似文献   
66.
The antibacterial activity of human lactoferrin from milk (hLF), recombinant human lactoferrin from Aspergillus awamori (rhLF) and their hydrolysates obtained with pepsin was investigated against Escherichia coli O157:H7, Salmonella Enteritidis and Listeria monocytogenes. The minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC) were determined for all the bacteria and the proteins assayed. Taking into account the MICs found for both lactoferrins studied, we can say that they behave very similarly, except for L. monocytogenes for which rhLF was more active. We studied the effect that heat treatments exerted on the antibacterial activity of the two types of lactoferrin and the only heat treatment that had a negative effect on that activity was 85 °C for 10 min. The activity of hLF and rhLF in UHT milk and whey against E. coli O157:H7 and L. monocytogenes, was also assayed. Our results showed a reduction in the number of viable cells for both microorganisms when were incubated with rhLF or hLF, but this decrease was lower than in broth media.  相似文献   
67.
This paper is a first attempt at documenting efficiency levels in Africa's electricity firms, their evolution and the sources of this evolution. The analysis is based on a sample of 12 operators providing services in the 12 country members of the Southern Africa Power Pool. We focus on the changes in total factor productivity (TFP) of the largest operators in each country between 1998 and 2005. We then rely on a data envelopment analysis (DEA) decomposition to identify the sources of the changes in TFP. The results suggest fairly comparable levels of efficiency in the region and performance levels and evolution quite independent of the degree of vertical integration, the presence of a private actor or the main sources of energy supply. The analysis suggest that although the companies have not made significant improvements during the period of analysis in using their capital and human assets, they have done much better in adopting better technologies and better commercial practices. No clear correlation could be associated with the adoption of reforms during the last decade and data limitations impede a more refined assessment of the impact of reforms on efficiency at this stage.  相似文献   
68.
The Tinto River (Iberian Pyritic Belt) is a unique ecosystem characterized by extreme acidity and abnormally high concentrations of heavy metals in water, sediments and alluvium, with high microbial diversity and low plant diversity. The low pH value, a direct consequence of the high amount of Fe and S derived from the bedrock, promotes the dispersion of heavy metals. Less mobile elements (Fe, As, Pb, Ag and Ti) show the highest concentrations in the mid stretches of the river while easily mobile metals (Cu, Zn and Cd) accumulate in the estuarine sediments. Tinto River soils show a scarcity of nutrients (Ca, K, P, Mg and Na) due to the lack of lithologic sources and to loss by acid washing. Sea water and phospho-gypsum deposits near Huelva contribute to increase the Na, Mg and P concentrations in the estuarine soils. As a whole these features represent an extreme habitat to which plants must adapt.  相似文献   
69.
The popularity of herbal products, especially plant food supplements (PFS) and herbal medicine is on the rise in Europe and other parts of the world, with increased use in the general population as well as among specific subgroups encompassing children, women or those suffering from diseases such as cancer. The aim of this paper is to examine the PFS market structures in European Community (EC) Member States as well as to examine issues addressing methodologies and consumption data relating to PFS use in Europe. A revision of recent reports on market data, trends and main distribution channels, in addition an example of the consumption of PFS in Spain, is presented. An overview of the methods and administration techniques used to assess individual food consumption as a starting point, including their uses and limitations, as well as some examples of studies that collect Food Supplement (FS) information, including herbal/botanical/plant-derived products are also discussed. Additionally, the intake estimation process of food nutrients is described and used to propose the PFS ingredients intake estimation process. Nationally representative PFS consumption data is scarce in Europe. The majority of studies have been conducted in Scandinavia and the UK. However the heterogeneity of definitions, study design and objectives make it difficult to compare results and extrapolate conclusions.  相似文献   
70.
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