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111.
The aim of this work was preparation of the macroporous titania coatings with the use of the sol–gel process and poly(methylmetacrylate) beads as a template. The effectiveness of the Langmuir–Blodgett (LB) and dip-coating (DC) methods in deposition of polymer beads on the silicon wafers was compared. Resulted polymer layers and final porous titania coatings were analyzed with the use of the atomic force microscope. It was found, that application of the LB is possible only when arachidic acid is present in the subphase. It should be highlighted, that the application of the LB method is the novelty between the methods of the polymer beads arrangement having the diameter of 200–300 nm. Main factors which influence the structure and the arrangement of polymer templates were the concentration of the polymer suspension and the rate of the substrate immersion/withdrawal from the suspension. We established, that the optimal concentrations for preparation of polymer templates, exhibiting good arrangement of individual beads, were 0.5 and 6 % for LB and DC methods, respectively. The size of pores of the obtained macroporous titania (200–330 nm) corresponds well with the size of the polymer beads used as the template (200–235 nm).  相似文献   
112.
Clear and cloudy apple juices from Idared and Champion varieties were studied for their radical‐scavenging effects. The polyphenolic content and composition of the juices before and after thiolysis were determined by high‐performance liquid chromatography with diode array detection. Cloudy juices, especially that prepared from Champion variety, had a higher content of procyanidins than clear juices. Radical‐scavenging activity was measured by electron paramagnetic resonance (EPR) spectroscopy using the stable 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical. All juices showed long‐lasting radical‐scavenging activity, and EPR spectra were recorded over time to follow the reaction kinetics. Scavenging of DPPH showed pseudo‐first‐order kinetics, which might be expected in the presence of polymerised antioxidants that prevent closer contact between the DPPH radical and hydroxyl groups. The content of polymeric procyanidins showed a linear dependence on the rate constant, suggesting that these compounds are mainly responsible for time‐extended radical‐scavenging activity. The antioxidant properties of apple juices were much better reproduced by EPR spectroscopy than by UV–visible measurements. The former method is especially sensitive to the concentration of polymerised or bound procyanidins, whilst the latter method requires transparent (clear) samples. Apple juices, especially cloudy ones, are a rich source of natural antioxidants that may be used in the pharmaceutical or food industry. Copyright © 2006 Society of Chemical Industry  相似文献   
113.
Although several meta‐analysis studies have been published comparing the quality of food derived from organic and non‐organic origin, it is still not clear if food from organic production per se can guarantee product‐related added value to consumers. This paper aims to summarize the status quo in order to identify research gaps and suggest future research challenges. Organic food is described according to a quality model already published. The influence of organic production on food quality is structured in primary production and processing. Furthermore, organic food authentication is discussed. Organic food seems to contain fewer pesticide residues and statistically more selected health‐related compounds such as polyphenols in plant products and polyunsaturated fatty acids in milk and meat products, but the health relevance for consumers is not clear yet. Comparing food from organic origin with so called ‘conventional’ food seems not to be appropriate, because ‘conventional’ is not defined. In organic food quality research a system approach is needed from which systemic markers can be selected. Research on the impact of processing technologies on the quality according to organic principles seems of high relevance, since most of the food is processed. © 2014 Society of Chemical Industry  相似文献   
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Flavonoid compounds are known for their antibacterial, anti-inflammatory, and anticancer properties. Therefore, they can influence membrane properties that interest us, modifying both their structure and functions. We used kaempferol (K) and myricetin (M) as representatives of this group. We investigated the influence of the abovementioned compounds on model cell membranes’ properties (i.e., Langmuir monolayers and liposomes). The basic research methods used in these studies were the Langmuir method with Brewster angle microscopy and microelectrophoresis. The π–A isotherms were registered for the pure components and mixtures of these compounds with phosphatidylcholine (PC) in appropriate volume ratios. Using mathematical equations, we established that kaempferol, myricetin, and the lipids formed complexes at 1:1 ratios. We derived the parameters characterizing the formed complexes, i.e., the surfaces occupied by the complexes and the stability constants of the formed complexes. Using the microelectrophoretic method, we determined the dependence of the lipid membranes’ surface charge density as a function of the pH (in the range of 2 to 10) of the electrolyte solution. The presented results indicate that the PC membrane’s modification with kaempferol or myricetin affected changes in the surface charge density and isoelectric point values.  相似文献   
117.
Nutritional value and physical and sensory quality characteristics of medium-grounded model canned meat products containing barley fibre preparation Vitacel BG300 (0.0%, 3.0% and 6.0%) were assessed. The results showed that regardless of the type of thermal treatment (pasteurisation and sterilisation), the addition of barley fibre did not significantly (P > 0.05) alter the content of the main nutrients (protein, fat and chlorides) in the block of canned meat product. Increasing the dose of barley fibre from 3.0% to 6.0% significantly increased (P < 0.05) the thermal loss in both pasteurised and sterilised canned meat products. The colour of the blocks of both pasteurised and sterilised canned meat products with barley fibre was significantly (P < 0.05) darker, and the instrumental hardness differed from the corresponding control products. Despite the beneficial nutritional effect of the Vitacel BG300 barley fibre preparation, its use significantly deteriorated the sensory quality of canned meat products.  相似文献   
118.
Heart failure (HF) is one of the major causes of morbidity and mortality worldwide and represents an escalating problem for healthcare systems. The identification of asymptomatic patients with underlying cardiac subclinical disease would create an opportunity for early intervention and prevention of symptomatic HF. Traditional biomarkers are very useful as diagnostic and prognostic tools in the cardiovascular field; however, their application is usually limited to overt cardiac disease. On the other hand, a growing number of studies is investigating the diagnostic and prognostic potential of new biomarkers, such as micro-RNAs (miRNA), long non-coding RNAs, and exosome cargo, because of their involvement in the early phases of cardiac dysfunction. Unfortunately, their use in asymptomatic phases remains a distant goal. The aim of this review is to gather the current knowledge of old and novel biomarkers in the early diagnosis of cardiac dysfunction in asymptomatic individuals.  相似文献   
119.
Novel bone substitutes such as highly porous ceramic scaffolds can serve as platforms for delivering active molecules. A common problem is to control the release of the drug, therefore, it is beneficial to use a drug-functionalized polymer coating. In this study, β-tricalcium phosphate-based porous scaffolds were obtained and coated with diclofenac-functionalized biopolymer – poly(3-hydroxyoctanoate) – P(3HO). To the best of our knowledge, studies using P(3HO) as a component in ceramic-polymer based drug delivery system for bone tissue regeneration have not yet been reported. Presented materials were comprehensively investigated by various techniques such as powder X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, hydrostatic weighing and compression tests, pH and ionic conductivity measurements, high-performance liquid chromatography and in vitro cytotoxicity studies. The obtained diclofenac-loaded composite was not only characterised by controlled and sustained drug release, but also possessed improved mechanical properties. Moreover, the precipitation of apatite-like forms on its surface was observed after incubation in simulated body fluid, which indicates its bioactive potential. After 24 hours no cytotoxic effect on MC3T3-E1 mouse preosteoblastic cells was confirmed using indirect cytotoxicity studies. Thus, this promising multifunctional composite scaffold can be a promising candidate as an anti-inflammatory drug-delivery system in bone tissue engineering.  相似文献   
120.
The treatment of memory impairments associated with the central nervous system diseases remains an unmet medical need with social and economic implications. Here we show, that a multi-target ligand of aminergic G protein-coupled receptors with antipsychotic activity in vivo (D2AAK1) stimulates neuron growth and survival and promotes neuron integrity. We focused on the multilevel evaluation of the D2AAK1-related effects on neurons in terms of behavioral, cellular, molecular, and biochemical features in vivo and in vitro, such as memory-related responses, locomotor activity, tissue sections analysis, metabolic activity, proliferation level, neurons morphology, and proteins level involved in intracellular signaling pathways. In silico studies indicate that activation of calcium/calmodulin-dependent protein kinase I (CaMKI) may underline some of the observed activities of the compound. Furthermore, the compound increases hippocampal neuron proliferation via the activation of neurotrophic factors and cooperating signals responsible for cell growth and proliferation. D2AAK1 improves memory and learning processes in mice after both acute and chronic administration. D2AAK1 also causes an increase in the number of hippocampal pyramidal neurons after chronic administration. Because of its neuroprotective properties and pro-cognitive activity in behavioral studies D2AAK1 has the potential for the treatment of memory disturbances in neurodegenerative and mental diseases.  相似文献   
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