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451.
A top fermented beer was brewed from 100% buckwheat malt and sensory and analytical characterisation was carried out. Difficulties with lautering and filtration were encountered during the brewing process, which resulted in problems during fermentation and beer filtration. The beer was evaluated in the fresh and forced aged state for the following attributes: odour, purity of taste, mouthfeel, tingling, and bitterness. Analytical results indicated that the buckwheat beer compared quite closely to a typical wheat beer with regard to pH, FAN, fermentability and total alcohol. However, the extract of the buckwheat wort was lower, resulting in a final extract yield of 54.5%. GC analysis of the resultant beer revealed commonly encountered levels of the esters that give beer a fruity character. A low level of fusel alcohols, in comparison to a typical wheat beer, was detected. A high level of ethyl caprinate (coconut flavour) and lauric acid (fatty odour) was detected. Sensory analysis indicated that the buckwheat beer was acceptable with regard to odour, purity of taste, mouthfeel, tingling and bitterness. In conclusion, results of this study prove buckwheat's qualification as a gluten‐free brewing material and with process optimisation, its readiness for marketing.  相似文献   
452.
Lacrima di Morro d’Alba is a red DOC (controlled designation of origin) wine, which is produced in the region of Marche (Italy) using the homonymous grape cultivar of Vitis vinifera. Lacrima di Morro contains the diglucosides of malvidin, petunidin, peonidin, whereas cyanidin and its derivatives were not detected with high performance liquid chromatography coupled with an ion trap mass spectrometer. Among anthocyanins, only the coumaroyl derivatives of peonidin and petunidin were positively related to copigmentation and color intensity, unlike malvidin-3-coumarylglucoside. Tannins (ranging only from less than 50–224 mg/L) and large polymeric pigments were indifferent with regard to copigmentation, whereas gallic acid and quercetin were the non-pigmented phenolics positively related to copigmentation and color intensity. (+)-catechin was related with a brown, oxidized hue and with non-copigmented anthocyanins. Copigmentation was positively related to the sour taste of the wine, but was negatively related to the astringent taste.  相似文献   
453.
Cauda  Emanuele  Fino  Debora  Saracco  Guido  Specchia  Vito 《Topics in Catalysis》2004,30(1-4):299-303
Topics in Catalysis - Perovskite-type catalysts have been investigated for diesel soot combustion: (i) the LaCr0.9O3?δ substoichiometric perovskite, (ii) K–La partially substituted...  相似文献   
454.
A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is a promising therapeutic approach to reduce gastrointestinal symptoms associated with irritable bowel syndrome (IBS). However, a shift toward a more sustainable, healthy diet with higher inclusion of whole-grain cereals (i.e., wheat, rye, barley) and pulses, naturally rich in FODMAPs, poses a severe challenge for susceptible individuals. Dietary restriction of fermentable carbohydrates (commonly called the “low FODMAP diet”) has received significant consideration. Hence, the development of functional low FODMAP products is emerging in food science and the food industry. In this review, we evaluate the most promising yet neglected (bio)-technological strategies adopted for modulating the FODMAP contents in complex food systems and the extent of their uptake in the global food market. We extensively investigated the global low FODMAP market, contrasted with the status quo in food science and discussed the key principles and concomitant challenges of targeted FODMAP reduction strategies. Powerful tools are available which are based either on the use of ingredients where FODMAPs have been physically removed (e.g., by membrane filtration) or biotechnologically reduced during the food processing, mediated by added enzymes, microbial enzymes during a fermentation process, and seed endogenous enzymes. However, <10% of the small market of functional products with a low FODMAP claim (total ∼800 products) used any of the targeted FODMAP reduction techniques. The global market is currently dominated by gluten-free products, which are naturally low in FODMAPs and characterized by inferior sensory attributes.  相似文献   
455.
Different pathogenic variants in the same protein or even within the same domain of a protein may differ in their patterns of disease inheritance, with some of the variants behaving as negative dominant and others as autosomal recessive mutations. Here is presented a structural analysis and comparison of the molecular characteristics of the sites in fibrinogen γ-module, a fibrinogen component critical in multimerization processes, targeted by pathogenic variants (HGMD database) and by variants found in the healthy population (gnomAD database). The main result of this study is the identification of the molecular pathogenic mechanisms defining which pattern of disease inheritance is selected by mutations at the crossroad of autosomal recessive and negative dominant modalities. The observations in this analysis also warn about the possibility that several variants reported in the non-pathogenic gnomAD database might indeed be a hidden source of diseases with autosomal recessive inheritance or requiring a combination with other disease-causing mutations. Disease presentation might remain mostly unrevealed simply because the very low variant frequency rarely results in biallelic pathogenic mutations or the coupling with mutations in other genes contributing to the same disease. The results here presented provide hints for a deeper search of pathogenic mechanisms and modalities of disease inheritance for protein mutants participating in multimerization phenomena.  相似文献   
456.
A population of 18-year-old males were studied in order to investigate which biohumoral parameters were modified with respect to the so-called "reference values." To achieve our end, we analyzed the distribution curves of some biohumoral parameters, so selected to test various organs and apparatuses. Our results showed a clear incidence of hepatic affections and dislipidemias.  相似文献   
457.
Miners are exposed to silica-bearing dust which can lead to silicosis, a potentially fatal lung disease. Currently, airborne silica is measured by collecting filter samples and sending them to a laboratory for analysis. Since this may take weeks, a field method is needed to inform decisions aimed at reducing exposures. This study investigates a field-portable Fourier transform infrared (FTIR) method for end-of-shift (EOS) measurement of silica on filter samples. Since the method entails localized analyses, spatial uniformity of dust deposition can affect accuracy and repeatability. The study, therefore, assesses the influence of radial deposition uniformity on the accuracy of the method. Using laboratory-generated Minusil and coal dusts and three different types of sampling systems, multiple sets of filter samples were prepared. All samples were collected in pairs to create parallel sets for training and validation. Silica was measured by FTIR at nine locations across the face of each filter and the data analyzed using a multiple regression analysis technique that compared various models for predicting silica mass on the filters using different numbers of “analysis shots.” It was shown that deposition uniformity is independent of particle type (kaolin vs. silica), which suggests the role of aerodynamic separation is negligible. Results also reflected the correlation between the location and number of shots versus the predictive accuracy of the models. The coefficient of variation (CV) for the models when predicting mass of validation samples was 4%–51% depending on the number of points analyzed and the type of sampler used, which affected the uniformity of radial deposition on the filters. It was shown that using a single shot at the center of the filter yielded predictivity adequate for a field method, (93% return, CV approximately 15%) for samples collected with 3-piece cassettes.

Copyright 2013 American Association for Aerosol Research  相似文献   
458.
This paper contributes to the literature on distance and quality by identifying a firm‐based force contributing to explain the observed increase of the quality of shipped goods with the distance of their destination market. This force originates from the influence of distance on firms' strategic behaviour in the presence of consumer heterogeneity, when the quality level of goods is a choice variable for them. Our approach differs from the extant literature because it does not rely on technology or preference/income differentials to identify the determinants and drivers of trade flows. We find that distance has an unambiguously positive effect on the average quality of traded goods. Our results contribute to the analysis of the determinants of firms' trade performance.  相似文献   
459.
In this work, step-index 40/125 μm diameter optical fibers produced from two slightly different lithium phosphate glasses were subjected to mechanical characterization. Tensile tests were carried out on fibers with gage length from 10 to 150 mm, allowing for the determination of the failure stress (ranging from ≈200 to 400 MPa) and the elastic modulus (60 GPa). Some tests were also performed with the fiber “immersed” in water; an important subcritical crack growth effect was pointed out, and a fatigue susceptibility parameter (n) equal to 11.4 was determined. The analysis of fracture mirror allows an estimated fracture toughness equal to 0.5 MPa m0.5.  相似文献   
460.
The aim of this work is to present a circuit model to analyze and design ultra wideband (UWB) radars for the remote monitoring of breath activity. The model includes the impulse signal source, the transceiver antenna, the transmission medium, and the human thorax. First of all, the proposed model has been validated by comparing its responses with those achieved both numerically, with a commercial electromagnetic modeling software, and experimentally, by means of a setup based on an indirect time domain reflectometry system. Then, the model has been used for analyzing the feasibility of a UWB radar operating in the 3–6‐GHz range with an effective isotropic radiated power lower than − 41.3 dBm/MHz, i.e. within the limits issued by the United States Federal Communications Commission for unlicensed UWB imaging systems. The model outlined the possibility of the considered UWB radar of monitoring the breath activity of a subject up to distances of about 10 m in open air. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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