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181.
BACKGROUND: Rocket salads (Diplotaxis tenuifolia and Eruca vesicaria) are presently highly appreciated salad vegetables. Related species are consumed as food plants in several regions, and may contribute to differentiation in the fresh food supply chain. Glucosinolates are well‐known healthy phytochemicals and responsible for positive and negative sensory properties of edible Brassicaceae. To investigate the potential for exploitation of new crops, Diplotaxis and Eruca germplasm was subject to sensory evaluation and glucosinolate analysis. RESULTS: Typical rocket salad flavour and pungency were perceived as positive sensory traits. Bitter, and especially herbaceous notes, characterised the groups of less accepted accessions. The groups classified as significantly unpleasant were characterised by high glucosinolate content, with either sinigrin (strong perceived pungency, flavour and several other additional sensory notes), or sinalbin/gluconapin (strong herbaceous note, low flavour perceived), as the dominant components. CONCLUSIONS: Low glucosinolate content, and a composition rich in recognised health‐promoting components (glucoerucin, glucoraphanin) were associated with higher acceptance. In relation to food uses, moderate glucosinolate content and high acceptance may be a better option to enhance the intake of healthy phytochemicals than high glucosinolates and potential rejection. High glucosinolate types may find better perspectives in the field of food integrators. Copyright © 2009 Society of Chemical Industry  相似文献   
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183.
The consumption of synthetic cannabinoids (SCs) has significantly increased in the last decade and the analysis of SCs and their metabolites in human specimens is gaining interest in clinical and forensic toxicology. A pilot study has been carried out using a combination of an initial last generation gas chromatography-mass spectrometry (GC-MS) screening method for the determination of JWH-122, JWH-210, UR-144) in oral fluid (OF) of consumers and an ultra-high performance liquid chromatography high resolution mass spectrometry (UHPLC-HRMS) confirmatory method for the quantification of the parent compounds and their metabolites in the same biological matrix. OF samples were simply liquid-liquid extracted before injecting in both chromatographic systems. The developed methods have been successfully validated and were linear from limit of quantification (LOQ) to 50 ng/mL OF. Recovery of analytes was always higher than 70% and matrix effect always lower than 15% whereas intra-assay and inter-assay precision and accuracy were always better than 16%. After smoking 1 mg JWH-122 or UR-144 and 3 mg JWH-210, maximum concentration of 4.00–3.14 ng/mL JWH-122, 8.10–7.30 ng/mL JWH-210 ng/mL and 7.40 and 6.81 ng/mL UR-144 were measured by GC-MS and UHPLC-HRMS respectively at 20 min after inhalation. Metabolites of JWH 122 and 210 were quantified in OF by UHPLC-HRMS, while that of UR144 was only detectable in traces. Our results provide for the first time information about disposition of these SCs and their metabolites in consumers OF. Last generation GC-MS has proven useful tool to identify and quantify parent SCs whereas UHPLC-HRMS also confirmed the presence of SCs metabolites in the OF of SCs consumers.  相似文献   
184.
Renal transplantation represents the most favorable treatment for patients with advanced renal failure and it is followed, in most cases, by a significant enhancement in patients’ quality of life. Significant improvements in one-year renal allograft and patients’ survival rates have been achieved over the last 10 years primarily as a result of newer immunosuppressive regimens. Despite these notable achievements in the short-term outcome, long-term graft function and survival rates remain less than optimal. Death with a functioning graft and chronic allograft dysfunction result in an annual rate of 3%–5%. In this context, drug toxicity and long-term chronic adverse effects of immunosuppressive medications have a pivotal role. Unfortunately, at the moment, except for the evaluation of trough drug levels, no clinically useful tools are available to correctly manage immunosuppressive therapy. The proper use of these drugs could potentiate therapeutic effects minimizing adverse drug reactions. For this purpose, in the future, “omics” techniques could represent powerful tools that may be employed in clinical practice to routinely aid the personalization of drug treatment according to each patient’s genetic makeup. However, it is unquestionable that additional studies and technological advances are needed to standardize and simplify these methodologies.  相似文献   
185.
Micropatterned collagen scaffold with axially oriented pores embedded with poly(lactide-co-glycolide) nanoparticles (PLGA NPs) was synthesized and characterized. Two different concentrations of PLGA nanoparticles have been tested and the experimental results indicate that the concentration affects the release kinetic, whereas the stiffness, the crosslink density, and the degradation rate of the collagen matrix are comparable to bare scaffold. Further, the proposed crosslinking procedure provides a resistance to thermal and enzymatic degradation, thereby promoting the persistence of scaffold for a period of time compatible with nerve regeneration.  相似文献   
186.
The aim of this study was to made and characterized a nanostructured surface on titanium mesh for cranioplasty, by adhesion of selenium nanoparticles (SeNPs) in situ, in a hydrothermal reaction. The structural characterization of selenium nanoparticles was performed using DLS and TEM, revealing that the size and morphology of nanoparticles depends on the nature of saccharide reducing agent. In situ hydrothermal reaction revealed that selenium nanoparticles adherence on titanium mesh surface had the best result in the case of starch-derived SeNPs, as demonstrated by SEM/EDX analysis. In vitro hemolysis and RBC osmotic fragility tests suggest that nanostructured surface created upon SeNPs adhesion doesn’t induce damage to RBC membrane; the hemolysis values indicated a good biocompatibility especially in the case of titanium specimens modified with starch-derived SeNPs. Moreover, the nanostructured surface clearly offers the desired biological response of human fibroblasts cells. The proposed improvement of the surfaces in the case of titanium mesh for cranioplasty may offer important benefits in terms of osteointegration, without using additional screws for fixation and closure procedure.  相似文献   
187.
Our recent research efforts identified racemic RC‐33 as a potent and metabolically stable σ1 receptor agonist. Herein we describe the isolation of pure RC‐33 enantiomers by chiral chromatography, assignment of their absolute configuration, and in vitro biological studies in order to address the role of chirality in the biological activity of these compounds and their metabolic processing. The binding of enantiopure RC‐33 to the σ1 receptor was also investigated in silico by molecular dynamics simulations. Both RC‐33 enantiomers showed similar affinities for the σ1 receptor and appeared to be almost equally effective as σ1 receptor agonists. However, the R‐configured enantiomer showed higher in vitro hepatic metabolic stability in the presence of NADPH than the S enantiomer. Overall, the results presented herein led us to select (R)‐RC‐33 as the optimal candidate for further in vivo studies in an animal model of amyotrophic lateral sclerosis.  相似文献   
188.
The adsorption abilites of cotton cellulose fibers are very often modified by alkaline treatments in form of alkaline purification or mercerization using high concentration of NaOH. We tried to determine the correlation between morphological modifications and the adsorption abilities of cotton fibers using several methods: the analysis of microscope images of fibers by image processing and the analysis of the electrokinetic surface properties which express the adsorption behavior of fibers. The longitudinal images and cross-sections of native and modified cotton fibers were analyzed and the parameters: form factor, wall thickness, cross-section area, fiber diameter, lumen area were calculated using image processing. The adsorption behavior of native and NaOH modified polymers was investigated by the determination of electrokinetic properties. The zeta potential (ζ) was calculated from streaming potential measurements as a function of pH and surfactant concentration in the liquid phase. The results indicate that only a correct combination between the morphological modifications and electrokinetic behavior of fibers leads to a desirable adsorption mechanism which causes a specific adsorption of components of the liquid phase.  相似文献   
189.
High-performance alicyclic-containing polyimides for advanced applications, derived from 5-(2,5-dioxotetrahydrofurfuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride or bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and two flexible aromatic diamines, were synthesized by a classical two-step polycondensation reaction and analyzed by rheological method. The results were discussed according to the chemical structure of polyimides and their different properties, such as flexibility, hydrophobicity and surface morphology. It has been showed that the obtained parameters, controlled by the interactions occurring in the polyimide systems, can be correlated with the adhesion/cohesion of blood components and plasma proteins. Thus, the results of the work of spreading proteins on the hydrophobic polyimide surfaces indicated that albumin is not absorbed preferentially, while fibrinogen is characterized by a higher degree of adhesion on the surfaces, and also that selective adsorption of plasma proteins modifies blood compatibility. In addition, these results and the ascertained antimicrobial activity of the studied polyimides contribute to the development of new applications in the bio-technical field.  相似文献   
190.
Despite of the variety of existing techniques, there is still a continuous demand in the development of more efficient recycling technologies, for economic and environmental reasons. A new approach for recycling EPDM rubber waste has been recently introduced utilizing a solvent free activation process by addition of liquid polymers (LP). The present study investigates the influence of the content and varying types of activated rubber waste particles (RWP‐LP) in new composites. By varying the proportion of RWP‐LP in the range from 25 up to 75 v/v % information about optimized compositions of new compounds were obtained. It was found that the ratio and type of RWP‐LP induce significant differences in terms of cure characteristics, mechanical properties, crosslink density and morphology. Promising results with high potential application for the production of seal and sealing systems on the industrial scale were obtained by using up to 50 v/v % of RWP‐LP with low ethylene amount. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42097.  相似文献   
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