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41.
A range of blackberry genotypes harvested in different seasons and regions in Mexico (Michoacan) and in the United States (Pacific Northwest) were collected to determine their antioxidant capacity using oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays. Total acidity, ascorbic acid, soluble solids, total phenols, and total anthocyanins, as well as the correlation between all these parameters, were determined for all treatments. Total acidity ranged from 4.22% in wild blackberry from Patzcuaro, Mexico, to 1.02% in ‘Evergreen’ from Woodburn, Oreg. These treatments were also the outliers in terms of ascorbic acid content. Cultivar ‘Brazos’ did not exhibit any significant differences in acidity or ascorbic acid as a consequence of the geographic origin or harvest season. The highest concentration of soluble solids was recorded for ‘Evergreen’ from Woodburn and relatively low soluble solids levels were recorded for all the Mexican treatments. Wild blackberry from Patzcuaro exhibited the highest values for ORAC, FRAP, total phenolic and anthocyanin content. Other relatively high antioxidant capacity values were detected for ‘Marion’ and ‘Evergreen’, both produced in Oregon. Different cultivars grown in the same region/season consistently showed differences in antioxidant capacity. There was little effect of harvest season on phenolic levels. We conclude that levels of total acidity, ascorbic acid, soluble solids, antioxidant capacity, and polyphenols mainly depended on the genotype and not on the climate or the season. ORAC and FRAP values were both highly correlated with each other, and with total phenols and anthocyanin content.  相似文献   
42.
Cranberry pomace is a byproduct of cranberry processing and is comprised of seeds, skins and stems of the cranberry fruit. While cranberry pomace contains beneficial polyphenols, including proanthocyanidins and anthocyanins, it is not a palatable source of these compounds and is typically discarded. In this study, we have developed and optimized a method to extract polyphenols from cranberry pomace using aqueous ethanol, a food grade solvent. Biochemical characterization of the pomace extract showed the presence of a broad range of polyphenols also present in cranberry juice concentrate. By co-drying cranberry pomace extract with a protein-rich food matrix, such as soy protein isolate (SPI), we have developed a method to produce a cranberry polyphenol–SPI complex (CBP-SPI) containing 10% cranberry polyphenols. Unlike dried cranberry pomace extract alone, proanthocyanidins, anthocyanins and total polyphenols were found to be highly stable at 37 °C in the CBP-SPI powder. The extraction and stabilization of cranberry pomace polyphenols using SPI provides an innovative approach for utilizing pomace in the development of novel food ingredients.  相似文献   
43.
In solid oxide fuel cells (SOFC) for operating temperatures of 800 °C or below, the interconnection plates can be made from stainless steel. This is a big economic advantage, but energy losses can be caused by undesirable reactions between the alloys and other SOFC components. The use of coatings on interconnect stainless steels can reduce this degradation. A MnCo1.9Fe0.1O4 (MCF) spinel not only significantly decreases the contact resistance between a La0.8Sr0.2FeO3 cathode and a stainless steel interconnect, but also acts as a diffusion barrier to prevent Cr outward migration through the coating. The level of improvement in electrical performance depends on the ferritic substrate composition. For Crofer22APU and F18TNb, with a Mn concentration of 0.4 and 0.12 wt%, respectively, the reduction in contact resistance is significant. In comparison, limited improvement is achieved by application of MCF on IT-11 and E-Brite containing no Mn. No influence of the minor additions of Si or Al is observed on contact resistance. The MCF protection layer bonds well to the stainless steel substrates under thermal cycling, but the thermal expansion difference is too large between the La0.8Sr0.2Co0.75Fe0.25O3 contact layer used and Crofer22APU and IT-11.  相似文献   
44.
Diets high in bioactive compounds, such as polyphenols, have been used to mitigate metabolic syndrome (MetS). Polyphenols are a large group of naturally occurring bioactive compounds, classified into two main classes: non-flavonoids and flavonoids. Flavonoids are distributed in foods, such as fruits, vegetables, tea, red wine, and cocoa. Studies have already demonstrated the benefits of flavonoids on the cardiovascular and nervous systems, as well as cancer cells. The present review summarizes the results of clinical studies that evaluated the effects of flavonoids on the components of the MetS and associated complications when offered as supplements over the long term. The results show that flavonoids can significantly modulate several metabolic parameters, such as lipid profile, blood pressure, and blood glucose. Only theaflavin and catechin were unable to affect metabolic parameters. Moreover, only body weight and body mass index were unaltered. Thus, the evidence presented in this systematic review offers bases in support of a flavonoid supplementation, held for at least 3 weeks, as a strategy to improve several metabolic parameters and, consequently, reduce the risk of diseases associated with MetS. This fact becomes stronger due to the rare side effects reported with flavonoids.  相似文献   
45.
Business Process Re-engineering (BPR) is being used to improve the efficiency of the organizational processes, however, a number of obstacles have prevented its full potential from being realised. One of these obstacles is caused by an emphasis on the business process itself at the exclusion of considering other important knowledge of the organization. Another is due to the lack of tools for identifying the cause of the inefficiencies and inconsistencies in BPR. In this paper we propose a methodology for BPR that overcomes these two obstacles through the use of a formal organizational ontology and knowledge structure and source maps. These knowledge maps are represented formally to facilitate an inferencing mechanism which helps to automatically identify the causes of the inefficiencies and inconsistencies. We demonstrate the applicability of this methodology through the use of a case study of a university domain.  相似文献   
46.
47.
ABSTRACT

Knowledge sharing can be hindered by barriers that prevent the free flow of information, especially across organizational and other boundaries. Therefore information produced at one location might not be available to entities elsewhere even if there are benefits to sharing this information. This can often lead to 'reinventing the wheel' and wasted investments in duplicating resources and ultimately will lead to the development of knowledge silos. Information technologies can be used to address this problem as they provide opportunities to lower the barriers to knowledge sharing and increase collaboration. This need for knowledge sharing and collaborative technologies can be important for Small Island Developing States (SIDS) within particular regions that are exposed to similar environmental and economic issues that can hinder their development. Although each SIDS may have Knowledge Resources that it uses to address its own issues, there would be benefits to collaborating and sharing these resources to collectively tackle these regional issues. Even when there is a willingness to share and collaborate and entities have been established to foster this collaboration, there is a void in the availability of tools and technologies needed to support collaboration and sharing of resources. This paper describes the research that has been done to help fill this void by designing and developing a technological solution, a Knowledge Broker, for the identification and sharing of Knowledge Resources that may be spread across various locations (e.g. countries). The Design Science Research methodology was used to develop the Knowledge Broker architecture, which provides a single point of access to the knowledge resources within a particular domain. A critical component of this Knowledge Broker is a common, online interactive vocabulary of the domain of interest which provides the terms which are used to describe and search for the knowledge resources available. The Knowledge Broker was evaluated using informed arguments and an illustrative scenario in the Comprehensive Disaster Management domain in the Caribbean region. The initial evaluations that have been reported in this paper indicates that the Knowledge Broker has the potential to increase the efficiency of solving regional issues through the sharing of knowledge resources.  相似文献   
48.
The in-mold coating (IMC) process nowadays is well accepted by the sheet molding compound industry. The currently used IMC contains 2.8 wt% carbon black (CB) to provide enough electrical conductivity for maximum paint transfer efficiency (PTE) for electrostatic painting. Due to its relatively large viscosity, this formulation makes use of more than one injection gate for coating some large parts necessary. Our previous research investigated the possibility to replace the CB with higher conductivity carbon-based nanoparticles, namely carbon nanofibers (CNFs), multi-wall carbon nanotubes (MWCNTs), industrial graphene (grapheneblack [G]), and single-wall carbon nanotubes (SWCNTs) and found that the IMC with 11.3 wt% G has the best processability among all IMC formulations. To improve this formulation, herein, we study the use of a second reinforcement in combination with G, i.e., CB, CNF, and MWCNT. Results from this study suggest that most G/CB-reinforced IMC formulations have a better performance than the G-reinforced IMC formulations, and IMC with 1 wt% CB and 6 wt% G is the best among all G/CB-reinforced IMC formulations. To be specific, the new formulation allows parts to be painted to have a 300% increase in size when compared with the standard IMC.  相似文献   
49.
L. Sueiro    G.G. Yousef    D. Seigler    E.G. de Mejia    M.H. Grace    M.A. Lila 《Journal of food science》2006,71(8):C480-C488
ABSTRACT:  European plantation-bred (cultivated) and local Illinois (wild) Aronia melanocarpa (chokeberry) fruits were extracted with 70% aqueous acetone and separated into 6 fractions using vacuum liquid chromatography (VLC) over a Toyopearl (TP) polymer column. TP fractions 2 through 6 were recombined and further subfractionated using silica gel (SG) into 22 subfractions. Crude extract, TP fractions, and SG subfractions were screened in a L1210 murine leukemia cell assay and a human DNA catalytic topoisomerase II assay in order to gauge the cancer chemopreventive potential of each genotype. SG subfraction 6 from the cultivated genotype showed >90% inhibitory activity at 25 μg/mL, and a similar fraction from the wild genotype showed >95% inhibitory activity to L1210 leukemia cells at a concentration of 50 μg/mL. On the basis of topoisomerase inhibition, it can be concluded that all TP fractions of the wild genotype act as catalytic inhibitors. Similar anthocyanins and oligomeric proanthocyanidins were identified from both Aronia genotypes; however, HPLC-ESI-MS spectra indicated higher flavonoid concentration in the wild Aronia and a predominance (up to 67%) of nonphenolic compounds in the berries from the cultivated genotype. Both cultivated and wild genotypes exhibited promise toward chemoprevention, but differed in levels of activity in the assays used to determine chemoprotective potential.  相似文献   
50.
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