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71.
In this study the authors examine the effects of procedures adapted from the cognitive interview of R. E. Geiselman, R.P. Fisher, D.P. MacKinnon, and H.L. Holland (1985) on children's recall following exposure to misleading suggestions. Children aged 5-7 years and 9-11 years saw a videotaped story and were presented with misleading or neutral information concerning story details. All were later given free- and cued-recall tests preceded by standard interview instructions or instructions that reinstated the encoding context and encouraged exhaustive reporting. Increased recall accuracy was found following cognitive interview instructions. Both age groups were susceptible to misleading suggestions, but susceptibility was unaffected by interview type. The authors discuss the implications for interviewing child witnesses.  相似文献   
72.
In the course of isolating and analyzing the fatty acid methyl esters (FAME) from steelhead trout (Salmo gairdneri) eggs and sac fry, a component was found on gas liquid chromatography to have a retention time longer than any characteristic polyunsaturated fatty acid previously encountered in trout. Subsequent purification and analysis demonstrated this component to be cholesterol. Thus, cholesterol and related compounds can interfere in the analysis of FAME when the methyl esters are prepared by transesterification.  相似文献   
73.
Between November 1979 and November 1981, 17,086 test-day milk samples were collected from individual Holstein cows in 62 Quebec herds. Samples were analyzed for protein, fat, casein, serum protein, somatic cell count, and the relative percentages of β-lactoglobulin, α-lactalbumin, bovine serum albumin, and the immunoglobulins. Cows included in the study were phenotyped with respect to β-lactoglobulin. Unadjusted means ± standard error for the relative percentages of β-lactoglobulin, α-lactalbumin, bovine serum albumin, and immunoglobulins were 64.80 ± .07%, 21.54 ± .05%, 6.51 ± .02%, and 7.15 ± .04%. Least-square analyses showed that month of test, stage of lactation, age of cow, somatic cell count, and phenotype of the cow for β-lactoglobulin had significant effects on the relative percentages of β-lactoglobulin, α-lactalbumin, bovine serum albumin, and immunoglobulins. Test-day milk yield, fat percent, protein percent, casein percent, casein number, and serum protein percent, when included in a statistical model as covariates, had a significant effect on the relative percentage of Ig. Relative proportion of β-lactoglobulin and α-lactalbuminim were not significantly affected by serum protein and total protein contents. For bovine serum albumin, only the covariates fat percent and serum protein percent were not significant.  相似文献   
74.
Rapid detection of airborne fungal and bacterial spores would enable public agencies to respond quickly and appropriately to intentional releases of hazardous aerosols. Automated analysis of microscope images and automated detection of near-monodisperse peaks in aerosol size distribution data offer complementary approaches to traditional methods for the identification and counting of fungal and bacterial spores. First, spores of the fungus Scopulariopsis brevicaulis were aerosolized in a chamber and then collected with a slit impactor; later, digital microscope images were analyzed manually to determine spore cluster distributions. The images also were analyzed with ImageJ, a program that automatically outlined objects and measured Feret's diameter, area, perimeter, and circularity. These characteristics were used to identify spore clusters automatically using two data analysis methods. Second, a computer program was developed to discriminate near-monodisperse bioaerosol peaks from those for polydisperse ambient particulate matter (PM) and was successfully tested using simulated and real aerosol mixtures. The observed agreement between manual and automated spore counts and the ability to detect spore peaks suggest that it may be possible to develop a system to recognize intentional releases rapidly through examination of particle morphology and size distributions. The peak detection procedure is potentially the fastest technique when used with real-time instrument data, but assumes that intentional releases would consist of large numbers of uniformly sized particles in the respirable size range.

Copyright 2012 American Association for Aerosol Research  相似文献   
75.
Cleland LG  Gibson RA  Pedler J  James MJ 《Lipids》2005,40(10):995-998
Flaxseed, echium, and canola oils contain α-linolenic acid (18∶3n−3, ALA) in a range of concentrations. To examine their effect on elevating cardiac levels of long-chain n−3 FA, diets based on these n−3-containing vegetable oils were fed to rats for 4 wk. Sunflower oil, which contains little ALA, was a comparator. Despite canola oil having the lowest ALA content of the three n−3-containing vegetable oils, it was the most potent for elevating DHA (22∶6n−3) levels in rat hearts and plasma. However, the relative potencies of the dietary oils for elevation of EPA (20∶5n−3) in heart and plasma followed the same rank order as their ALA content, i.e., flaxseed>echium>canola>sunflower oil. This paradox may be explained by lower ALA intake leading to decreased competition for Δ6 desaturase activity between ALA and the 24∶5n−3 FA precursor to DHA formation.  相似文献   
76.
Congenital cataracts (CC) are responsible for approximately one-tenth of childhood blindness cases globally. Here, we report an African American family with a recessively inherited form of CC. The proband demonstrated decreased visual acuity and bilateral cataracts, with nuclear and cortical cataracts in the right and left eye, respectively. Exome sequencing revealed a novel homozygous variant (c.563A > G; p.(Asn188Ser)) in GJA3, which was predicted to be pathogenic by structural analysis. Dominantly inherited variants in GJA3 are known to cause numerous types of cataracts in various populations. Our study represents the second case of recessive GJA3 allele, and the first report in African Americans. These results validate GJA3 as a bona fide gene for recessively inherited CC in humans.  相似文献   
77.
Isothermal conduction calorimetry has been used to monitor the early hydration of Portland–blastfurnace slag (BFS)-blended cements. Portland:BFS composite cements with ordinary Portland cement replacements from 0 to 90 wt% were studied at curing temperatures from 12° to 90°C. Peak II, principally associated with alite (Ca3SiO5) hydration, was accelerated with increasing temperature for all blends. Peak S, associated with BFS hydration, was particularly noticeable at 40° and 60°C. At higher curing temperatures, peak S merged with peak II, indicating thermal activation of BFS. Novel plots of total heat output against percentage replacement show that BFS contributes to the heat of hydration, even at temperatures below its thermal activation.  相似文献   
78.
Diffraction prevents the focusing of ultraviolet and visible radiations within nanoscaled volumes and, as a result, the imaging and patterning of nanostructures with conventional far-field illumination. Specifically, the irradiation of a fluorescent or photosensitive material with focused light results in the simultaneous excitation of multiple chromophores distributed over a large area, relative to the dimensions of single molecules. It follows that the spatial control of fluorescence and photochemical reactions with molecular precision is impossible with conventional illumination configurations. However, the photochemical and photophysical properties of organic chromophores can be engineered to overcome diffraction in combination with patterned or reiterative illumination. These ingenious strategies offer the opportunity to confine excited chromophores within nanoscaled volumes and, therefore, restrict fluorescence or photochemical reactions within subdiffraction areas. Indeed, information can be "read" in the form of fluorescence and "written" in the form of photochemical products with resolution down to the nanometre level on the basis of these innovative approaches. In fact, these promising far-field optical methods permit the convenient imaging of biological samples and fabrication of miniaturized objects with unprecedented resolution and can have long-term and profound implications in biomedical research and information technology.  相似文献   
79.
Fructose oleate, an environmentally-friendly biobased surfactant, was prepared using solvent-free suspensions of saccharide in a mixture of acyl donor and monoester (the latter present at ≥5 wt% initially) continuously recirculated through a closed-loop packed bed bioreactor (PBBR)-based system at 53 °C, with the PBBR containing immobilized Rhizomucor miehei lipase (Lipozyme®IM, Novozymes, Franklinton, NC, USA). To replenish the acyl acceptor consumed during the time course of reaction, the medium was isolated, fructose added, and a suspension formed by rigorous stirring at 80 °C for 6 h followed by centrifugation to remove larger particles, with the placement of the acyl acceptor replenishment treatments during the time course of reaction were optimized. Water removal via free evaporation was augmented during the latter portion of the time course (using a molecular sieve packed column, N2 bubbling, vacuum pressure, or a combination of the latter two), with an optimal performance achieved when initiating N2 + vacuum (\( 2. 1 6\,{\text{mg}}_{{{\text{H}}_{ 2} {\text{O}}}} \,{\text{h}}^{{^{ - 1} }} \) removal rate) upon reaching 60% ester, to maintain the liquid-phase water content near 0.40 wt%. When employing the above-mentioned conditions, 92.6 wt% fructose oleate was produced within 132 h, yielding a productivity of \( 0. 2 9 7\,{\text{mmol}}_{\text{Ester}} \,{\text{h}}^{ - 1} \, {\text{g}}_{\text{lipase}}^{ - 1} \).  相似文献   
80.
The results of an experimental and computational investigation of the selective separation of carbohydrates on nano‐membranes in cross‐flow filtration are reported. Two commercial membranes (NF270‐400 and TFC‐SR3) were characterised in terms of permeability and rejection of carbohydrate solutions. It is shown that the membranes can be used to recover glucose and galactose from their mixtures with lactose. The permeate flux is shown to depend on sugar concentration, with permeate flux decreasing as the concentration increases. Quantitative evaluation using numerical analysis of the above flow and separation process showed that the performance of nano‐membranes can be captured and reproduced with sufficient accuracy, thereby reducing the number of experiments require to evaluate the suitability of membranes in different applications. A Fickian approach is adopted to model the separation, and is shown to be effective.  相似文献   
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