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101.
The State of Paraiba in Northeastern Brazil ranks as the fourth poorest state in the country. The objectives of this study are to conduct the psychometric validation of the Brazilian Household Food Insecurity Scale (EBIA), to assess the household food insecurity (HFI) prevalence, and to identify the association between HFI, poverty and dietary intake in a representative sample of Paraiba’s 14 poorest municipalities (N = 4533). All municipalities included had fewer than 50,000 inhabitants. EBIA had strong internal consistency (Cronbach’s alpha = 0.93 and 0.90 in households with and without children, respectively). The percentage of affirmative responses for each item was inversely associated with household income and the item curves were parallel across socio-economic strata. Rasch modeling indicated that: a) scale items severities followed theoretical expectations, b) all items had an adequate fit to the scale confirming its unidimensionality, and c) items ‘functioned’ similarly across key subpopulation characteristics including: urban/rural; men/women; younger/older; poor/less poor; Bolsa Familia enrollment (yes/no). HFI prevalence was higher in rural than in urban areas (55.5 % vs. 49.9 %, p < 0.0005) and severe food insecurity was substantially higher in rural areas (14.0 % vs. 9.0 %, p < 0.0005). HFI severity was inversely associated with household income, positively associated with daily sugar consumption and inversely associated with daily consumption of bread and nutrient dense foods (fruits, vegetables, and dairy). In conclusion, EBIA had strong internal and external validity at the municipal level. Findings are particularly relevant for Brazil where 89.1 % of municipalities (4,957 out of 5,565 municipalities) have less than 50,000 inhabitants.  相似文献   
102.
103.
Estolides are bio-based oils synthesized from fatty acids or from the reaction of fatty acids with vegetable oils. Estolides have many advantages as lubricant base oils, including excellent biodegradability and cold flow properties. Promising applications for estolides include bio-lubricant base oils and in cosmetics. In this review, the synthesis of estolides from fatty acids using four different types of catalysts, namely, mineral acids, solid acids, lipases, and ionic liquids, is summarized. The summary includes the yield of estolide obtained from varying synthetic conditions (time, temperature, catalyst). Also reviewed are studies comparing the physical properties of estolides synthesized from refined fatty acids against those synthesized from fatty acid mixtures obtained from vegetable oils such as coconut, castor, Physaria, etc. By varying the structure of the fatty acids, estolides with a wide range of pour point, cloud point, and viscosity are synthesized to meet a wide range of application requirements. Currently, estolide products are being commercialized for personal care and lubricant base oils for automotive, industrial, and marine applications. The application areas and the demand for estolides is expected to grow as the drive for switching from petroleum to bio-based products keeps growing.  相似文献   
104.
The link between impaired maternal behavior (MB) and cocaine treatment could result from drug-induced decreases in maternal reactivity to offspring, prenatal drug exposure (PDE) in offspring that could alter their ability to elicit MB, or the interaction of both, which could subsequently impair MB of the 1st-generation dams. Following chronic or intermittent cocaine or saline treatment during gestation, rat dams rearing natural or cross-fostered litters were compared along with untreated dams for MB. Untreated 1st-generation females with differentially treated rearing dams and PDE were tested for MB with their natural litters. The authors report disruptions in MB in dams and their 1st-generation offspring, attributable to main and interaction effects of maternal treatment, litter PDE, and rearing experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Caddisfly larvae (Limnophilus spp.) are important predators of eggs of the rough-skinned newt (Taricha granulosa). Newts may possess extremely large quantities of the neurotoxin tetrodotoxin (TTX) in their skin, and females may provision this toxin in their eggs. Using a competitive inhibition enzymatic immunoassay, we examined TTX-resistant caddisflies, sympatric with the known most toxic population of newts, for the presence of TTX. We found that caddisflies sequester TTX after consuming eggs in the laboratory. Caddisfly larvae that were frozen immediately after collecting in the wild possessed TTX. Finally, wild-caught larvae reared on a TTX-free diet in the laboratory retained TTX for up to 134?days, through metamorphosis and into the adult stage.  相似文献   
106.
Review of biodiesel composition, properties, and specifications   总被引:4,自引:0,他引:4  
Biodiesel is a renewable transportation fuel consisting of fatty acid methyl esters (FAME), generally produced by transesterification of vegetable oils and animal fats. In this review, the fatty acid (FA) profiles of 12 common biodiesel feedstocks were summarized. Considerable compositional variability exists across the range of feedstocks. For example, coconut, palm and tallow contain high amounts of saturated FA; while corn, rapeseed, safflower, soy, and sunflower are dominated by unsaturated FA. Much less information is available regarding the FA profiles of algal lipids that could serve as biodiesel feedstocks. However, some algal species contain considerably higher levels of poly-unsaturated FA than is typically found in vegetable oils.Differences in chemical and physical properties among biodiesel fuels can be explained largely by the fuels’ FA profiles. Two features that are especially influential are the size distribution and the degree of unsaturation within the FA structures. For the 12 biodiesel types reviewed here, it was shown that several fuel properties - including viscosity, specific gravity, cetane number, iodine value, and low temperature performance metrics - are highly correlated with the average unsaturation of the FAME profiles. Due to opposing effects of certain FAME structural features, it is not possible to define a single composition that is optimum with respect to all important fuel properties. However, to ensure satisfactory in-use performance with respect to low temperature operability and oxidative stability, biodiesel should contain relatively low concentrations of both long-chain saturated FAME and poly-unsaturated FAME.  相似文献   
107.
Delineation of tumor margins is a critical and challenging objective during brain cancer surgery. A tumor-targeting deep-blue nanoparticle-based visible contrast agent is described, which, for the first time, offers in vivo tumor-specific visible color staining. This technology thus enables color-guided tumor resection in real time, with no need for extra equipment or special lighting conditions. The visual contrast agent consists of polyacrylamide nanoparticles covalently linked to Coomassie Blue molecules (for nonleachable blue color contrast), which are surface-conjugated with polyethylene glycol and F3 peptides for efficient in vivo circulation and tumor targeting, respectively.  相似文献   
108.
This research investigated how voters select, process, are affected by, and recall political information in a dynamic campaign environment. It was hypothesized that voters' information selection, processing, and recall are subject to a negativity bias (i.e., negative information dominates over positive information), a congruency bias (i.e., positive information about the preferred candidate and negative information about the opponent candidate dominate over negative information about the preferred candidate and positive information about the opponent), and a candidate bias (i.e., information about the preferred candidate dominates over information about the opponent). Motivated by an initial candidate preference, participants were also expected to develop more polarized candidate evaluations over time. Participants were exposed to quickly changing information in the form of newspaper-style headlines on a dynamic, computer-based information board. The results generally supported negativity bias and candidate bias, whereas congruency bias was only found during information recall. At the information selection and processing stages, participants with a strong initial candidate preference showed a disproportionate preference for negative information about the preferred candidate. However, they developed more positive attitudes at the evaluation and recall stage. This finding suggests that participants were engaged in motivated information processing by counterarguing negative information about their preferred candidate.  相似文献   
109.
Clinical lore abounds when discussing the issue of treating trauma-related symptoms in substance-dependent clients. Historically, clinicians have wondered whether they should wait until the client has gained substantial abstinence from abused substances before initiating trauma treatment or if trauma treatment should be conducted during substance use treatment. Furthermore, questions arise with regard to exactly how trauma-related symptoms should be addressed and how trauma treatment should be incorporated into the recovery process. In this article, the growing literature suggesting that posttraumatic stress disorder (PTSD) can be treated concurrently with substance use disorders is reviewed. In addition, the unique challenges of implementing treatment for PTSD with substance-dependent clients seeking treatment in a residential treatment facility are discussed. Specifically, we provide concrete suggestions about how to utilize prolonged exposure, a very effective treatment for PTSD, with clients in a residential substance use treatment facility, including use of the internet to facilitate exposure therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Research on the typical development of reading comprehension, individual differences in comprehension, and reading comprehension interventions is less common than research on word reading. The authors present an overview of research on the development of reading comprehension skills and sources of individual differences in comprehension with reference to cognitive models of comprehension. Methodological issues particular to developmental and individual difference research on comprehension are also described. The article ends with a selective review of research programmes that illustrate effective comprehension interventions for typically developing children and for children who struggle to understand what they read. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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