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81.
Varietal wines are defined as made primarily from a single variety of grape, which is identified on the label. However the inclusion of other varieties in their production is permitted under defined percentages. The fact that different grape varieties/varietal wines present far different economical values can attract fraudulent practices. Thus the development of methods, which allow the quantification of those varieties, is of crucial importance. The first approach to the method for the relative quantification of must containing two varieties based on microsatellite DNA analysis is presented. Quantification was achieved by densitometry measurements of the amplification products of the pooled varieties, obtained with loci VVMD6 and VVMD7, after their separation and staining on polyacrilamide gels. We have found that a good correlation between the proportion of each variety in must and the signal intensity of the alleles are dependent on the variety (varietal effect) and the microsatellite locus used. The relative quantification of musts can be accomplished by the presented method depending on the presence of overlapping alleles, and the composition of the varieties and their relative amounts.  相似文献   
82.
83.
Using a specially constructed apparatus, diffusion bonding of SU 263 alloy was studied in the temperature range of 1123–1323 K and compressive stress of 90% of its yield strength at the corresponding temperatures to determine the relative importance of the process parameters, the mechanism(s) responsible for bonding and the joint characteristics. Bond quality was assessed by optical metallography and lap shear testing. The mechanism of bonding was evaluated by grain growth equation. The experimental results were compared with a model developed by Pilling [Pilling, J., 1988. The kinetics of isostatic diffusion bonding in superplastic materials. Mater. Sci. Eng. 100, 137–144] in which the void closure by creep flow and diffusion are considered. Quantified EPMA line scan analysis was carried out to confirm the bonding mechanism and to determine the composition at the interface.  相似文献   
84.
The photoluminescence (PL), radioluminescence (RL) and thermoluminescence (TL) of KMgF3 doped at several Sm concentrations have been investigated. The maximum TL and RL yield under beta irradiation has been observed in KMgF3:Sm 0.02 mol%. The glow curve of this doped perovskite is made up of at least five peaks located at 95, 120, 160, 270, and 330 °C. The third peak appears to be the most convenient for personal or environmental dosimetry, since it shows no fading and good linearity within the investigated dose range (0.020-200 Gy). From the RL and PL spectra it has been found that most of KMgF3:Sm emission is located at wavelengths higher than 650 nm. This emission, which is characteristic of Sm2+, makes this doped compound attractive for fiber-optic dosimetry.  相似文献   
85.
The control of gelato powder mixture production usually is carried out evaluating the gelato liquid phase. The rheological measurements from the present study were conduced on gelato unfrozen liquid phase in order to indirectly evaluate its rheological properties by FT-NIR spectroscopy applied on gelato powders. The calibration set was composed by samples obtained from different recipes having increasing percentage of thickeners, maintaining the proportions of the others compounds constant. After the NIR acquisitions the powders were mixed with warm milk, blended and than settled in order to obtain the unfrozen liquid phase needed for the rheological measurements. For each of the 60 tested recipes three batches with the same thickeners concentration were prepared. The flow curves were obtained with a rotational viscosimeter and were evaluated by using the Ostwald de Waele’s equation and the goodness of fit was evaluated by the R2, which was above 0.95. Predictive models of rheological parameters were set up by means of PLS regressions in order to predict the apparent viscosity (η), the consistency coefficient (K) and the flow behaviour index (n) from spectral acquisitions. A high correlation of calibration was found between NIR spectra and apparent viscosity with R2 of 0.943. A good correlation was also found between the NIR spectra and the consistency coefficient (K) and flow behaviour index (n), with a determination coefficient (R2) of 0.895 and 0.874, respectively.The good prediction of the models encourages applying them to reduce significantly the time of the powder mixing control during production.  相似文献   
86.
The physical and structural evolution of alumina films deposited by ALCVD annealed at high temperatures in N2 has been studied.Low temperature post deposition treatments in NH3 (PDN) have been performed to evaluate the impact of nitrogen incorporation in the alumina film on its thermal stability. Thermal evolution has been studied by deep UV spectroscopic ellipsometry and grazing X-ray reflectance techniques. AFM measurements were also performed to confirm and complete the ellipsometric and GXR analysis.The change of the crystalline structure was detected by ellipsometry by the different UV refractive index, while the GXR provided a unique thickness evaluation.It was therefore possible to determine the layer densification after the thermal treatment and the impact of the PDN on the transition temperature.  相似文献   
87.
Solid photocatalysts in which the 2,4,6-triphenylpyrylium (TP) or 2,4,6-triphenylthiapyrylium cation (TTP) are encapsulated within zeolite Y or deposited on mesoporous silica are used as photosensitizers for the oxidation of sulfides, both aromatic and aliphatic, in solvents of various polarity. Contrary to the same cations in solution, these solid sensitizers are not significantly degraded during operation. An effective oxygenation takes place leading to sulfoxides, disulfides, sulfinic and sulfenic esters as well as sulfonic acids. This large scope method shows a limited dependence on the substrate structure and on conditions and is suitable for the abatement of sulfur-containing pollutants.  相似文献   
88.
Exogenous melatonin is used in a number of situations, first and foremost in the treatment of sleep disorders and jet leg. However, the hypnotic, antinociceptive, and anticonvulsant properties of melatonin endow this neurohormone with the profile of a drug that modulates effects of anesthetic agents, supporting its potential use at different stages during anesthetic procedures, in both adults and children. In light of these properties, melatonin has been administered to children undergoing diagnostic procedures requiring sedation or general anesthesia, such as magnetic resonance imaging, auditory brainstem response tests and electroencephalogram. Controversial data support the use of melatonin as anxiolytic and antinociceptive agents in pediatric patients undergoing surgery. The aim of this review was to evaluate available evidence relating to efficacy and safety of melatonin as an analgesic and as a sedative agent in children. Melatonin and its analogs may have a role in antinociceptive therapies and as an alternative to midazolam in premedication of adults and children, although its effectiveness is still controversial and available data are clearly incomplete.  相似文献   
89.
The tetrasaccharide 4, a substructure of ganglioside GQ1balpha, shows a remarkable affinity for the myelin-associated glycoprotein (MAG) and was therefore selected as starting point for a lead optimization program. In our search for structurally simplified and pharmacokinetically improved mimics of 4, antagonists with modifications of the core disaccharide Galbeta(1-3)GalNAc, as well as the terminal alpha(2-3)- and the internal alpha(2-6)-linked neuraminic acid were synthesized and tested in target-based binding assays. Compared to the reference tetrasaccharide 4, the most potent antagonist 17 exhibits a 360-fold improved affinity. Furthermore, pharmacokinetic parameters such as stability in the cerebrospinal fluid, logD and permeation through the BBB indicate the drug-like properties of antagonist 17.  相似文献   
90.
A rapid Fourier transformed infrared (FTIR) attenuated total reflectance (ATR) spectroscopic method was applied to the determination of water content (WC), total phenol amount (TP) and antioxidant activity (ABTS . +) of virgin olive oils (VOO) and olive oils. Calibration models were constructed using partial least squares regression. Oil samples with WC ranging from 289 to 1402 mg water/kg oil, with TP from 46 to 877 mg gallic acid/kg oil and with ABTS . + from 0 to 5.7 mmol Trolox/kg oil were considered for chemometric analysis. Better results were obtained when selecting suitable spectral ranges; in particular, from 2260 to 1008 cm?1 for WC, from 3610 to 816 cm?1 for TP and from 3707 to 1105 cm?1 for ABTS . +. Satisfactory LOD values by the FTIR‐chemometric methods were achieved: 9.4 (mg/kg oil) for WC; 12.5 (mg gallic acid/kg oil) for TP, and 0.76 (mmol Trolox/kg oil) for ABTS . +. The evaluation of the applicability of these analytical approaches was tested by use of validation sample sets (n = 16 for WC, n = 11 for TP and n = 14 for ABTS) with nearly quantitative recovery rates (99–114%). The FTIR–ATR method provided results that were comparable to conventional procedures. Practical applications : The presented method is based on ATR–FTIR in combination with multivariate calibration methodologies and permits a simultaneous evaluation of important quality parameters of VOO (WC, TP and ABTS . +). This approach represents an easy and convenient means for monitoring olive oil quality with the advantage of ease of operation, speed, no sample pretreatment and no consumption of solvents. The data obtained with this method are comparable to those obtained using the official reference method. Therefore, the technique is highly plausible as an alternative to the standard procedure for routine analysis or control at‐line of production processes.  相似文献   
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