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161.
In this paper, silicon nanocrystals (Si-NCs) fabricated by Chemical Vapor Deposition (CVD) are successfully integrated in a 32 Mb ATMEL NOR Flash memory product, processed in a 130 nm technology platform. Different Si-NC deposition conditions are explored and the threshold voltage distributions of the arrays are correlated to the Si-NC size/dispersion. Main reliability characteristics, as endurance and data-retention after cycling, are studied. Results obtained on large arrays are related to single cell characteristics. The large set of data measured on arrays clearly demonstrates the robustness of our process and integration scheme.  相似文献   
162.
Investigations have been conducted on some samples of naturally desiccated horse-chestnuts (Aesculus hippocastanum), representative of the two most common mediterranean varieties: the pure species (AHP, giving white flowers), and a hybrid (AHH, giving pink flowers). Different experimental techniques have been used to gain more information on morphological structure and chemical composition of these complex matrices. Surface analysis by SEM showed no differences in such floured samples (wild type), while thermal behaviour (DSC) outlines some significant differences between them. Chemical composition reveals some differences in residual moisture (AHP = 6.97%; AHH = 6.59%), proteins (AHP = 2.64%; AHH = 1.82%), lipids (AHP = 4.13%; AHH = 5.10%), glucides (AHP = 15.2%; AHH = 14.3%), and ashes (AHP = 2.51%; AHH = 2.19%). Most likely, these characters modulate other undifferentiated chemical parameters, such as cold water solubility (CWS:AHP = 53.9%; AHH = 48.6%), and total inorganic soluble salts (TISS:AHP = 2.18%; AHH = 1.92%). Principal component analysis was applied to differentiate the two horse-chestnuts varieties. In particular, the first principal component effectively distinguish and discriminates AHH and AHP samples in two well-separated categories, giving, at the same time, some information on the influence of the whole set of chemical compositional parameters.  相似文献   
163.
The aim of this study was to investigate the relationship between the sensory characteristics of beer and food that harmonically complement each other respectively from the consumer or the sommelier point of view. With this in view, the most desirable beer and everyday Italian food combinations were explored. Eighteen beer samples, easily available in the off‐premise chain in Italy, and 9 dishes of Italian cuisine, were selected. The level of match of each beer and food combination was determined by a group of 51 consumers and by seven food experts using a 9‐point Likert‐like scale of suitability. Agreements and disagreements between food professionals and consumers were studied and discussed. Generally speaking, most of the dishes were poor complements to the beers selected for this study, for both regular consumers and experts. In particular, seafood salad, spaghetti with tomato sauce and creamed vegetable soup were inappropriate to nearly all of the beer samples overall. However, both consumers and experts found appropriate and interesting beer and food pairing choices, despite usually indicating different ideal beer samples and different levels of match for the same food. This confirmed that certain flavours of food and beer mix together better than others and indicates that consumers may have a different perception of the level of match between beer and food from experts. For regular consumers, the suitability to food was found to positively correlate with the sensory liking of beer. Furthermore the pairing suitability was not equivalent across consumer gender and age class, although these differences had a moderate to weak effect on the level of the final match. Correlations between sensory properties of food and beer samples are reported and discussed.  相似文献   
164.
Pistachio kernels were extracted with n-hexane and the oil obtained was saponified with methanolic KOH. The extracted unsaponifiable matter was fractionated on Thin Layer Chromatography (TLC) plates. The band with Rf = 0.47, analysed by Gas Chromatography–Mass Spectrometry (GC–MS), showed the presence of long-chain alkylphenols: this is the first time that alkylphenols are reported in pistachio kernels. To elucidate the structures, Nuclear Magnetic Resonance (NMR) and GC–MS analyses (on the trimethylsilyl derivatives) were used. Sixteen different 3-alkylphenols (cardanols) with a saturated, monounsaturated and diunsaturated chain were detected. A reaction with dimethyl disulphide was successfully used to determine the double bond position in the monounsaturated compounds. Three phenols were new natural compounds. The most abundant cardanols were 3-(8-pentadecenyl)-phenol, 3-(10-pentadecenyl)-phenol, 3-pentadecyl-phenol and 3-(10-eptadecenyl)-phenol. Total amount of cardanols in the oils (mean of five samples) was roughly evaluated as 440 ± 95 mg kg−1.  相似文献   
165.
Alternaria molds are known to cause the contamination of food with their secondary metabolites, a chemically very heterogeneous group of compounds. Yet, after decades of research on the occurrence and the toxicity of Alternaria toxins in academia, no regulation has been implemented yet, thus leaving these potential food contaminants in the status of so-called “emerging mycotoxins”. However, research on this topic has been far from static, leading to the European Food Safety Authority repeatedly calling for more data on the occurrence and toxicity of genotoxic metabolites such as alternariol (AOH) and its monomethyl ether (AME). To give an overview on recent developments in the field, this comprehensive review summarizes published data and addresses current challenges arising from the chemical complexity of Alternaria’s metabolome, mixture effects and the emergence of novel biological targets like cell membranes or the interaction with different receptors. Besides toxicodynamics, we review recent research on toxicokinetics, including the first in vivo studies which incorporated the rarely investigated—but highly genotoxic—perylene quinones. Furthermore, a particular focus lies on the advances of liquid chromatography/tandem mass spectrometry (LC-MS/MS)-based analytical tools for determining a broader spectrum of Alternaria toxins including modified/masked forms and assessing exposure via human biomonitoring (HBM).  相似文献   
166.
Flavonoids present in skin extracts of red seedless table grape varieties Summer Royal, Autumn Royal, and Crimson, and white seedless varieties Carati and Thompson were analyzed by HPLC-DAD-MS, in 3 y of study (2006 to 2008). The anthocyanins, delphinidin-3-O-glucoside, cyanidin-3-O-glucoside, petunidin-3-O-glucoside (with their corresponding p-coumaroyl derivatives), peonidin-3-O-glucoside, and malvidin-3-O-glucoside (with their corresponding acetyl, caffeoyl, and p-coumaroyl derivatives) were found. In addition the flavonols quercetin-3-O-glucuronide, quercetin-3-O-rutinoside, quercetin-3-O-glucoside, kaempferol-3-O-glucoside, kaempferol-3-O-galactoside, and the flavan-3-ols procyanidin B1, procyanidin B2, and catechin were also detected. Anthocyanins were the main flavonoids in red grapes ranging from 24 (Crimson) to 500 (Summer Royal) mg/kg fresh weight of grapes; consistent levels of flavonols and flavan-3-ols were also quantified in all varieties. To determine the effective climatic influence on flavonoids content in field conditions, viticultural practices have been developed, that could exclude the effects of direct solar radiation from confounding the assessment of those related to thermal conditions alone. A strong positive correlation was determined between flavonoids and temperature data that seem to be responsible for the difference of these metabolites along the years; furthermore, it has been possible to define a linear relationship (R(2) = 0.6871, P = 0.0057) between thermal amplitude and total flavonoids values in the red grapes. PRACTICAL APPLICATION: Grapes are economically the most important fruit species in the world and approximately 30% of its production is used as fresh fruit. Because of the very important role of flavonoids in food quality as well as their health-promoting properties, and considering that our experiments were performed along 3 consecutive years, gathered results in this research are quite promising to give a useful information on the flavonoid contents and their evolution in 5 seedless table grapes that are widespread in Mediterranean regions but also in California and South America, and are grown in a viticultural climate (Apulia, South Italy) very close to some regions of Spain, Turkey, Tunisia, and Israel.  相似文献   
167.
The aim of this research was to genetically and technologically characterize Candida zemplinina strains isolated from different sources of enological interest. Phenotypic and genotypic subtyping, as well as enological characterization, were carried out on 36 C. zemplinina isolates collected from grapes, must and wines of different regions of Italy. RAPD-PCR fingerprinting of the isolates revealed a high genetic heterogeneity. At physiological level, yeasts were grouped into different clusters on the basis of sugar and ethanol tolerance. Common enological characteristics were examined and strains resulted to be highly fructophilic while presenting low ethanol and acetic acid production, high glycerol production, capacity to metabolize malic acid and slower fermentation kinetics when compared to Saccharomyces cerevisiae.The genetic and phenotypic intraspecies biodiversity of C. zemplinina gave useful data to understand its potential technological role in winemaking. This research represents a first step for the selection of C. zemplinina strains to be used as a starter in co-culture or in sequential inoculation with S. cerevisiae to improve the complexity and to enhance the particular characteristic of wines.  相似文献   
168.
The growth of selected, indigenous Saccharomyces cerevisiae added as starters (SRS1, MS72 and RT73) was monitored during Montepulciano d'Abruzzo wine production. In all the fermentations the addition of the starter, caused a decrease of the non-Saccharomyces yeasts. When strains MS72 and RT73 were used as starters they were detected in the first phases of fermentations, while strain SRS1 competed successfully with native yeasts during all the process. Wines obtained by fermentation with the indigenous starters showed some different characteristics, according to the chemical and sensory analyses. This study highlighted that among selected starters with high fermentative capacity, some are able to dominate better than other natural wine yeast biota, whereas some strains can interact and survive besides native yeast populations during the fermentation. As a consequence, the dominance character can have a positive or negative effect on wine quality and has to be considered in the frame of yeast selection in order to improve or characterize traditional wines. Winemakers could choose among different degrees of yeast dominance to modulate the interaction among starter and native wine yeast population.  相似文献   
169.
Near-infrared spectroscopy (NIRS) has been widely used to determine various composition traits of many dairy products in the industry. In the last few years, near-infrared (NIR) instruments have become more and more accessible, and now, portable devices can be easily used in the field, allowing the direct measurement of important quality traits. However, the comparison of the predictive performances of different NIR instruments is not simple, and the literature is lacking. These instruments may use different wavelength intervals and calibration procedures, making it difficult to establish whether differences are due to the spectral interval, the chemometric approach, or the instrument's technology. Hence, the aims of this study were (1) to evaluate the prediction accuracy of chemical contents (5 traits), pH, texture (2 traits), and color (5 traits) of 37 categories of cheese; (2) to compare 3 instruments [2 benchtop, working in reflectance (R) and transmittance (T) mode (NIRS-R and NIRS-T, respectively) and 1 portable device (VisNIRS-R)], using their entire spectral ranges (1100–2498, 850–1048, and 350–1830 nm, respectively, for NIRS-R, NIRS-T and VisNIRS-R); (3) to examine different wavelength intervals of the spectrum within instrument, comparing also the common intervals among the 3 instruments; and (4) to determine the presence of bias in predicted traits for specific cheese categories. A Bayesian approach was used to develop 8 calibration models for each of 13 traits. This study confirmed that NIR spectroscopy can be used to predict the chemical composition of a large number of different cheeses, whereas pH and texture traits were poorly predicted. Color showed variable predictability, according to the trait considered, the instrument used, and, within instrument, according to the wavelength intervals. The predictive performance of the VisNIRS-R portable device was generally better than the 2 laboratory NIRS instruments, whether with the entire spectrum or selected intervals. The VisNIRS-R was found suitable for analyzing chemical composition in real time, without the need for sample uptake and processing. Our results also indicated that instrument technology is much more important than the NIR spectral range for accurate prediction equations, but the visible range is useful when predicting color traits, other than lightness. Specifically for certain categories (i.e., caprine, moldy, and fresh cheeses), dedicated calibrations seem to be needed to obtain unbiased and more accurate results.  相似文献   
170.
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