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981.
The objective of this study was to evaluate the fatty acid profile and glycerol concentration in cachaças aged for 3 years in barrels made from different types of tropical woods and European oak. Glycerol gives body to spirits, whereas the fatty acid profile influences the spirit sensory characteristics. The concentration of these compounds in aged spirits depends on the wood composition. Tropical wood barrels made from amendoim (Pterogyne nitens Tul), araruva (Centrolobium tomentosum), cabreúva (Myrocarpus frondosus), cerejeira (Amburana cearensis), grápia (Apuleia leiocarpa), ipê roxo (Tabebuia heptaphylla), jequitibá (Cariniana estrellensis), jequitibá rosa (Cariniana legalis) and pereira (Platycyamus regnellii), as well as European oak (Quercus petraea), were used in this study. Glycerol concentrations in aged cachaças were measured using colorimetric methods, and fatty acid profiles were determined by GC‐MS analysis. The main fatty acids found were propanoic (C3:0), butanoic (C4:0), pentanoic (C5:0), octanoic (C8:0), decanoic (C10:0), dodecanoic (C12:0), hexadecanoic (C16:0), octadecanoic (C18:0) and octadecenoic (C18:19) acids. Araruva barrels stood out as the major supplier of C4:0 and cabreúva barrels provided greater amounts of C18:0 to cachaça. Carvalho and araruva barrels conferred more complete fatty acid profiles and higher concentrations of glycerol. Copyright © 2016 The Institute of Brewing & Distilling  相似文献   
982.
983.
984.
A highly sensitive micelle-mediated extraction methodology for the preconcentration and determination of trace levels of cadmium by molecular fluorescence has been developed. Metal was complexed with o-phenanthroline (o-phen) and eosin (eo) at pH 7.6 in buffer Tris medium and quantitatively extracted into a small volume of surfactant-rich phase of PONPE 7.5 after centrifugating. The chemical variables affecting cloud point extraction (CPE) were evaluated and optimized. The RSD for six replicates of cadmium determinations at 0.84 μg L−1 level was 1.17%. The linearity range using the preconcentration system was between 2.79 × 10−3 μg L−1 and 2.81 μg L−1 with a correlation coefficient of 0.99. Under the optimal conditions, it obtained a LOD of 8.38 × 10−4 μg L−1 and LOQ of 2.79 × 10−3 μg L−1. The method presented good sensitivity and selectivity and was applied to the determination of trace amounts of cadmium in commercially bottled mineral water, tap water and water well samples with satisfactory results. The proposed method is an innovative application of CPE-luminescence to metal analysis comparable in sensitivity and accuracy with atomic spectroscopies.  相似文献   
985.
A system for visual surveys of bottom fishes, assembled from readily available components, is described. A camera and a depth sounder transducer are mounted on a towed body. The camera captures the images, and the depth sounder measures the distance between the camera and the bottom. A video recorder is used to record the data—the video channel for the image, and the audio channel for distance information, which is dictated from the depth sounder display into a microphone. A relationship between distance and magnification is used to estimate the width of the survey path and the size of surveyed objects. A comparison of round goby (Apollonia melanostoma) density estimated by repeated seining and use of the underwater visual apparatus showed that the smallest individuals are underrepresented by the visual assessment, but the visual method detects about 85% of the 50 mm TL or larger gobies.  相似文献   
986.
Barley starch was oxidized to different levels and the morphological, physicochemical and structural of the resultant oxidized barley starch were determined and compared with oxidized corn starch at the same oxidation level. The amylose content in oxidized starches decreased with increasing oxidation level, and the extent of decrease was similar for both starch types. No evidences of alteration in morphology and X‐ray diffraction pattern were noted after oxidation. The crystallinity of barley starch increased with increasing oxidation but corn starch displayed a reduced crystallinity at 5% NaOCl. The onset and peak gelatinization temperatures of oxidized starches as measured by differential scanning calorimetry showed a slight increase up to 3% NaOCl and then decreased at 5% NaOCl, whereas gelatinization enthalpy gradually decreased with increasing oxidation level. The melting temperature of retrograded oxidized starches increased with increasing oxidation. Both amylose and amylopectin were degraded during oxidation, but a higher degradation in both components as determined by high‐performance size‐exclusion chromatography (HPSEC) was noted for barley starch than for corn starch. Results of amylopectin chain‐length distribution showed that the proportions of A and B1 chains significantly increased while that of B2+ chains significantly decreased. These results suggest that differences in the structure of barley and corn starches affected their responses to oxidation. Barley starch seemed to be more susceptible to oxidation with more significant reduction in pasting temperature, viscosity, and molecular size than corn starch.  相似文献   
987.
Children's early approaches to learning (ATL) enhance their adaptation to the demands they experience with the start of formal schooling. The current study uses individual growth modeling to investigate whether children's early ATL, which includes persistence, emotion regulation, and attentiveness, explain individual differences in their academic trajectories during elementary school. Using data from the Early Childhood Longitudinal Study – Kindergarten Cohort (ECLS-K), the present investigation examined the association between ATL at kindergarten entry and trajectories of reading and math achievement across 6 waves of data from kindergarten, 1st, 3rd, and 5th grade (n = 10,666). The current study found a positive link between early ATL and individual trajectories of reading and math performance. Overall, children's early ATL was equally beneficial for children regardless of their race/ethnicity and dimensions of their socioeconomic background. However, links between early ATL and academic trajectories differed by their gender and initial levels of math and reading achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
988.
As sucking habits and eating behavior may be interrelated and also associated with taste, body composition, and sociodemographic factors, the objective was to perform an exploratory analysis to identify groups of children with a high degree of association between intragroup subjects, providing explanation and interpretation of the data. The study initially included 352 prepubertal children (197 girls; 7‐ to 11‐year‐old), from whom information about sociodemographic characteristics, duration of breastfeeding, past bottle‐feeding and non‐nutritive sucking habits, taste sensitivity, body mass index (BMI), and consistency of food ingested were collected. Salivary concentrations of amylase and total protein were also determined. Data were submitted to cluster analysis (hierarchical analysis, K‐means, and silhouette plot), one‐way ANOVA and correlation tests. Cluster analysis included 159 children, generating three reliable and meaningful clusters: Cluster 1 (labeled “good tasters”), was characterized by older children and higher taste sensitivity; Cluster 2 (“softer food consistency”) by longer bottle‐feeding duration and children who eat food with lower consistency, and Cluster 3 (“breastfed”) by longer breastfeeding duration (silhouette coefficient = 0.61). Cluster 3 also showed the higher percentage of normal‐weight children, normal delivery, maternal schooling, and lower rate of past non‐nutritional sucking habit. No correlation was found between salivary amylase and total protein concentrations, taste sensitivity and BMI, although taste sensitivity showed to be higher among girls (p = 0.002; power = 88%). The study identified three clusters, highlighting the relationship between nutritional sucking habits, consistency of food ingested, and sociodemographic characteristics. Most importantly, a close relation between bottle‐feeding and consumption of soft food consistency was observed.  相似文献   
989.
The typology, number, size, and distribution pattern of labellar and palpal sensilla of male and female Lutzomyia longipalpis (Lutz and Neiva, 1912) sand flies were analyzed by scanning electron and light microscopy, contributing to the construction of a gustatory and olfactory map in this important vector species. About 35 trichoid sensilla, sorted into three different classes according to their lengths, are present on the two labellar lobes. Five distinct structures are observed in the maxillary palps, which could be classified as noninnervated (microtrichia and scales) or the following innervated structures: 1) campaniform sensilla, found near the distal end of palpal segments II and III; 2) multiporous capitate peg sensilla, found in reduced number (1-6) on segment II, but located in a group of 15-25 on the distal third part of segment III; and 3) trichoid sensilla, distributed linearly on segment IV and spirally on segment V. Light microscopy analysis of silver-stained specimens indicated the presence of pores in the trichoid sensilla and their chemosensory function is discussed, as well as the possible function of the other sensilla.  相似文献   
990.
The optimization of supercritical fluid extraction using CO2 for the extraction of contaminants in 15 samples of recycled paper and board (P&B) has been studied. An experimental design was used for simultaneous optimization of the variables involved in both the extraction step and the collection of the extract. Methanol was used as modifier. Several plastisizers such as diethyl phthalate, diisobutyl phthalate, di-n-butyl phthalate, dioctyl adipate, and diethylhexyl phthalate (from 2 to 100 microg/g of paper) were found in the recycled P&B samples. A discriminate analysis applied to all results obtained allow us to classify the samples in three different groups according to the content of recycled pulp (0, 10-30, and > 80% of recycled pulp), the sample thickness (from <300 to >600 microm), and the surface treatment of the paper. The analytical behavior and the results are discussed.  相似文献   
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