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31.
In this study, antioxidant and antihemolytic activities of ethanolic extract of flowers, leaves, and stems of Hyssopus officinalis L. Var. angustifolius were investigated employing different in vitro assay systems. Extracts showed good antioxidant activity. IC50 for 1,1-diphenyl-2-picryl hydrazyl radical-scavenging activity were 148.8 ± 4.31 μg mL?1 for flowers, 79.9 ± 2.63 μg mL?1 for stems, and 208.2 ± 6.45 μg mL?1 for leaves. All extracts showed moderate iron (II) chelating ability. Extracts exhibited good antioxidant activity in the hemoglobin-induced linoleic acid model and also they were capable of scavenging hydrogen peroxide in a concentration dependent manner. Extracts showed good antihemolytic activity againts hydrogen peroxide-induced hemolysis (IC50 were 48.51 ± 2.27 μg mL?1 for flowers, 19.47 ± 0.73 μg mL?1 for leaves, and 63.1 ± 2.65 μg mL?1 for stems). The total amount of phenolic compounds in the extracts was determined as gallic acid equivalents and total flavonoid content was calculated as quercetin equivalents from a calibration curve.  相似文献   
32.
Powder Metallurgy and Metal Ceramics - In this study, the effects of molar ratio of the raw materials (TiO2 and Al) and the addition of Mg on the titanium aluminide–alumina composite...  相似文献   
33.
Atherosclerosis is a major cause of human cardiovascular disease, which is the leading cause of mortality around the world. Various physiological and pathological processes are involved, including chronic inflammation, dysregulation of lipid metabolism, development of an environment characterized by oxidative stress and improper immune responses. Accordingly, the expansion of novel targets for the treatment of atherosclerosis is necessary. In this study, we focus on the role of foam cells in the development of atherosclerosis. The specific therapeutic goals associated with each stage in the formation of foam cells and the development of atherosclerosis will be considered. Processing and metabolism of cholesterol in the macrophage is one of the main steps in foam cell formation. Cholesterol processing involves lipid uptake, cholesterol esterification and cholesterol efflux, which ultimately leads to cholesterol equilibrium in the macrophage. Recently, many preclinical studies have appeared concerning the role of non-encoding RNAs in the formation of atherosclerotic lesions. Non-encoding RNAs, especially microRNAs, are considered regulators of lipid metabolism by affecting the expression of genes involved in the uptake (e.g., CD36 and LOX1) esterification (ACAT1) and efflux (ABCA1, ABCG1) of cholesterol. They are also able to regulate inflammatory pathways, produce cytokines and mediate foam cell apoptosis. We have reviewed important preclinical evidence of their therapeutic targeting in atherosclerosis, with a special focus on foam cell formation.  相似文献   
34.
This study investigates the performance and hidden hydrogen consuming metabolic pathways of a fermentative side stream dynamic membrane (DM) bioreactor using flux balance analysis (FBA). The bioreactor was inoculated with untreated methanogenic seed sludge. It was found that fouling rate aggravated with increasing COD concentration (10–30 g/L) and was positively correlated to it rather than to the applied solid flux on the DM module. Due to increased fouling rate the hydraulic retention time (HRT) could not be reduced less than 0.82 ± 0.02 d. An increase in the organic loading rate (OLR) led to an increase in H2 yield from 0.01 to 0.76 mol H2/mol of sucrose. FBA revealed that homoacetogenesis was the main H2-consuming pathway at lower OLRs (corresponding to 10 and 15 g COD/L), while for the OLR corresponding to 30 g COD/L, homoacetogens were suppressed. More importantly, caproic acid production pathway was identified for the first time as another H2-consuming pathway at high OLR which was not significant at lower OLRs during fermentative dynamic membrane bioreactor operations.  相似文献   
35.
36.
A growing number of diseases in association with gluten intake, such as coeliac disease, have led to increasing demand for gluten-free products as a crucial economic and health issue. Gluten-free products, because of the absence of gluten, usually have a poor texture, taste and appearance. Therefore, the production of good quality gluten-free products with substances that can somehow mimic the viscoelastic properties of gluten is an important challenge. Recently, hydrocolloids are widely used to improve the quality and shelf-life of gluten-free products. In this study, the effect of hydrocolloids on the production of gluten-free cereal-based products, such as breads, cakes and muffins, biscuits and cookies, pasta and noodles, has been reviewed as well as their nutritional values. In general, this study could suggest key factors in the improvement of gluten-free products.  相似文献   
37.
As the complexity of software systems grows, it becomes increasingly difficult for developers to be aware of all the dependencies that exist between artifacts (e.g., files or methods) of a system. Change recommendation has been proposed as a technique to overcome this problem, as it suggests to a developer relevant source-code artifacts related to her changes. Association rule mining has shown promise in deriving such recommendations by uncovering relevant patterns in the system’s change history. The strength of the mined association rules is captured using a variety of interestingness measures. However, state-of-the-art recommendation engines typically use only the rule with the highest interestingness value when more than one rule applies. In contrast, we argue that when multiple rules apply, this indicates collective evidence, and aggregating those rules (and their evidence) will lead to more accurate change recommendation. To investigate this hypothesis we conduct a large empirical study of 15 open source software systems and two systems from our industry partners. We evaluate association rule aggregation using four variants of the change history for each system studied, enabling us to compare two different levels of granularity in two different scenarios. Furthermore, we study 40 interestingness measures using the rules produced by two different mining algorithms. The results show that (1) between 13 and 90% of change recommendations can be improved by rule aggregation, (2) rule aggregation almost always improves change recommendation for both algorithms and all measures, and (3) fine-grained histories benefit more from rule aggregation.  相似文献   
38.
We propose a proof-of-principle experiment to encode one logical qubit in noise protected subspace of three identical spins in a methyl group. The symmetry analysis of the wavefunction shows that this fermionic system exhibits a symmetry correlation between the spatial degree of freedom and the spin degree of freedom. We show that one can use this correlation to populate the noiseless subsystem by relying on the interaction between the electric dipole moment of the methyl group with a circularly polarized microwave field. Logical gates are implemented by controlling both the intensity and phase of the applied field.  相似文献   
39.
Alkoxides are the most common precursors used for the production of alumina nanopowders. These materials are, however, expensive and corrosive. This paper introduces a new method for the production of alumina nanopowders by rapid cooling of a synthetic caustic sodium aluminate solution (Bayer liquor), followed by calcination in the presence of a surface-stabilizing agent like 1,2-dihydroxy-3,5-benzene disulfonic acid disodium salt (Tiron). The powders produced are characterized by differential thermal analysis, XRD, transmission electron microscopy, scanning electron microscope, and Brunauer–Emmet–Teller. A nanopowder of α-alumina with an average crystallite size of 27.7 nm and an average particle size of 50 nm is produced.  相似文献   
40.
1,4-Diazabicyclo[2.2.2]octane (DABCO) has been used as an efficient and reusable solid base catalyst for the rapid and green synthesis of pyran annulated heterocyclic ring systems by the condensation reaction of various activated CH-acids and tetracyanoethylene under conventional heating and microwave irradiation in solvent-free conditions. Excellent yield, very short reaction time (2–5 min), operatinal simplity, easy work-up procedure, avoidance of hazardous or toxic catalysts, and organic solvents are the main advantages of this green methodology which makes it more economic than the other conventional methods.  相似文献   
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