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This study assessed 1500 adolescents from the National Longitudinal Study of Youth to test the hypothesis that African American mothers differentially socialize their girls and boys. The results showed that later-born boys had fewer chores, argued more with their mothers, lived in less cognitively stimulating homes, and were not allowed to make the same decisions as were the girls or firstborn boys at the same age. The later-born boys were also lowest in achievement and highest in externalizing behaviors. Parenting differences accounted for the achievement differences but not for the externalizing behavior differences. It was concluded that the later-born boys would achieve at the same rates as their siblings if they were socialized in the same manner as their siblings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Geotrichum candidum is a ubiquitous yeast and an essential component in the production of many soft cheeses. We developed a multilocus sequence typing (MLST) scheme with five retained loci (NUP116, URA1, URA3, SAPT4 and PLB3) which were sufficiently divergent to distinguish 40 sequence types (STs) among the 67 G. candidum strains tested. Phylogenetic analyses defined five main clades; one clade was restricted to environmental isolates, three other clades included distinct environmental isolates and dairy strains, while the fifth clade comprised 34 strains (13 STs), among which all but two were isolated from milk, cheese or the dairy environment. These findings suggest an adaptation to the dairy ecosystems by a group of specialized European G. candidum strains. In addition, we developed a polymerase chain reaction inter‐long terminal repeat scheme, a fast and reproducible random amplification of polymorphic DNA‐like method for G. candidum, to type the closely related dairy strains, which could not be distinguished by MLST. Overall, our findings distinguished two types of dairy strains, one forming a homogeneous group with little genetic diversity, and the other more closely related to environmental isolates. Neither regional nor cheese specificity was observed in the dairy G. candidum strains analysed. This present study sheds light on the genetic diversity of both dairy and environmental strains of G. candidum and thus extends previous characterizations that have focused on the cheese isolates of this species. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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The availability of total phenolics of date flesh (Pheonix dactylifera) in aqueous and acidified methanol and in vitro synergism of their antimutagenic and antioxidant activities were investigated. The antimutagenic activities of date flesh extracts tested against Salmonella strains TA-98 and TA-100 using Ames bacterial testing were in the range of 36.47 to 79.74% against the standard mutagens potassium dichromate and sodium azide. The antioxidant activities assessed as maximal inhibitory concentrations (IC50) for DPPH radicals and linoleic acid peroxidation inhibition were 812.90 to 2,076.10 μg/mL and 54.43 to 80.89%, respectively. The total phenolic contents of date flesh extracts (35.76 to 114.09mg/g of gallic acid equivalents) were found to be correlated with the biological activities. Use of 0.5 N acidified methanol was efficient for extraction of phenolic compounds with retained antioxidant and antimutagen activities. Dates are a good candidate as a source for development of chemotherapeutic drugs, nutracueticals, and functional food ingredients. 相似文献
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European Journal of Wood and Wood Products - Surface tension of solid wood surfaces affects the wettability and thus the adhesion of various adhesives and wood coatings. By measuring the contact... 相似文献
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Paula Emília Nunes Ribeiro Bellot Melissa Nunes Moia Bruna Zavarize Reis Lucia Fatima Campos Pedrosa Ljubica Tasic Fernando Barbosa Jr Karine Cavalcanti Maurício Sena-Evangelista 《Molecular nutrition & food research》2023,67(7):2200568
Phosphatidylcholines (PCs) are the major components of biological membranes in animals and are a class of phospholipids that incorporate choline as a headgroup. Lysophosphatidylcholines (LPCs) are a class of lipid biomolecules derived from the cleavage of PCs, and are the main components of oxidized low-density lipoproteins (oxLDLs) that are involved in the pathogenesis of atherosclerosis. Since obesity is associated with a state of chronic low-grade inflammation, one can anticipate that the lipidomic profile changes in this context and both PCs and LPCs are gaining attention as hypothetically reliable biomarkers of obesity. Thus, a literature search is performed on PubMed, Latin American and Caribbean Health Science Literature (LILACS), and Excerpta Medica DataBASE (Embase) to obtain the findings of population studies to clarify this hypothesis. The search strategy resulted in a total of 2403 reports and 21 studies were included according to the eligibility criteria. Controversial data on the associations of PCs and LPCs with body mass index (BMI) and body fat parameters have been identified. There is an inverse relationship between BMI and most species of PCs, and a majority of studies exhibited negative associations between BMI and LPCs. Other findings regarding the differences between PCs and LPCs in obesity are presented, and the associated uncertainties are discussed in detail. 相似文献
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Fatima Dayras Nicolas Chauvin 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2004,530(3):391-403
Compared to other alpha-particle emitting nuclides, for those with long half-lives (T1/2>106 years), there is generally some inconsistency and inaccuracy in the associated nuclear data. However, these radionuclides play a major role in modern society and, for a number of reasons, are the subject of widespread interest. The study of their alpha decay, which is more difficult than in the case of the other nuclides, enables knowledge of their nuclear data to be increased. In the present paper, we accordingly consider one of the most well known ones: 235U. Using a quasi mono-isotopic deposit of 235U obtained by electromagnetic separation, we have studied the alpha-particle decay of 235U using a high-energy resolution spectrometer developed in our laboratory. The stability of the spectrometer made it possible to perform long measurements which is crucial in the case of 235U. The Colégram program, with a new fit criterion to better take into account peaks of low statistical significance, was used to extract the data (alpha-particle emission probabilities and energies). Monte-Carlo simulations carried out in the context of this work were also used to corroborate the data obtained. Finally, thirteen alpha-particle emissions from 235U were measured, from which only ten were previously observed and measured. This work has substantially reduced the uncertainty concerning alpha-particle emission probability and energy values and has resolved some of the ambiguities concerning the 235U disintegration scheme to 231Th. 相似文献