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991.
Cross HR  West RL  Dutson TR 《Meat science》1981,5(4):261-266
The objective of the study was to compare the precision of the laser method for measuring sarcomere length with the precision of two oil-immersion microscope methods. Eighteen semitendinosus muscles were assigned to one of three post-mortem treatments to provide a wide range in sarcomere length. Two 5·0cm sections were removed from the centre of each muscle. Each section was subdivided into six equal-size pieces and randomly allotted to each of three participating institutions. Analysis of variance revealed that sarcomere length measurement was not significantly affected by the method of measurement or by the technician. For 99% precision, the laser method required 34 measurements, whereas the two microscope methods required 45 and 66 measurements, respectively.  相似文献   
992.
The mineral composition-iron (Fe), zinc (Zn), copper (Cu), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), fluoride (F), and phosphorus (P) (New Zealand lamb only)-of lean tissue from lamb retail cuts was studied. Twenty-four US lamb carcasses of different ages (5 to 11 months), geographical regions (Texas, Colorado and Montana) and USDA quality grades (Prime and Choice) and 27 New Zealand lamb carcasses from three weight groups (11 to 12·5 kg, 13 to 14·5 kg, and 16·5 to 18 kg), age rangining from 7 to 8 months, were selected for use in this study. Mineral concentrations were influenced more by retail cut and age than by quality grade or weigth group. Foreshank and shoulder cuts from both the US and New Zealand group consistently had the highest (P < 0·05) Zn content among the cuts. The K content of the muscle in US lambs increased as age increased, while the level of Ca and Zn in New Zealand lambs decreased as carcass weight increased. Except for Ca, the mineral concentrations of the lean tissue from US lambs were higher than the New Zealand lambs, although the differences were not always significant. US lambs had approximately 20%, 30% and 37% more Fe, Zn and Mg, respectively, but 27% less Ca than lean tissue from the New Zealand lambs.  相似文献   
993.
Attention has recently become focused on the performance advantages of nanocomposites, and particularly polymerbased nanocomposites with respect to incumbent “neat” polymers or metallic materials for lightweighting initiatives. In the interest of sustainability, the specific use of bioreinforced nanocomposite parts and nanostructured coatings within automotive, aerospace, construction, medical, and packaging applications is accelerating. These “green” nanocomposites can provide high mechanical strength at low density, low weight, and potentially low cost. However, there are interfacial surface adhesion challenges with these and other nanocomposites, in addition to particle distribution and stability issues, which can inhibit full realization of their mechanical performance advantages. This paper will profile polymeric nanocomposites and nanocoatings, as well as define surface modification protocols using atmospheric pressure plasma technologies to optimize interfacial adhesion to similar and dissimilar materials.  相似文献   
994.
This work aims to validate the design assumptions by the California Department of Transportation in order to better define the strategies used to design concrete structures with adequate corrosion mitigation and thus a “maintenance-free” service life. To this end, various laboratory tests were conducted to investigate the compressive strength of and chloride diffusivity in mortar and concrete samples with cement partially replaced by various minerals (class F and class N fly ash, ultra-fine fly ash, silica fume, metakaolin, and ground granulated blast-furnace slag), the porosity of mineral concretes, the freeze–thaw resistance of mineral mortars in the presence of deicers, and the effect of supplementary cementitious materials on the chloride binding and chemistry of the pore solution in mortar.  相似文献   
995.
A process for deposition of silicon oxycarbonitride films from poly(urea)methyl vinyl silazane (PUMVS) by spin coating precursor solutions onto a substrate, followed by polymerization, cross-linking and pyrolysis has been developed. The cross-linked polymer films (350 nm thick), deposited on variety substrates (e.g., silicon, sapphire, zirconia), were pyrolyzed in nitrogen or ammonia environments either in a hot isostatic press or in a tube furnace. Their microstructure was characterized using infrared and Raman spectroscopy. The tribological (friction and wear) behavior was evaluated in dry nitrogen and air with 50% relative humidity using a unidirectional linear wear tester in a ball-on-disk configuration. Wear surfaces, transfer films and wear debris were analyzed by scanning electron micrograph (SEM)/energy dispersive spectroscopy (EDS).  相似文献   
996.
The raspberry cane midge, Resseliella theobaldi, is a widespread pest of cultivated red raspberry in Europe. Pheromone-baited traps could provide a much-needed, accurate means to monitor the pest. Volatiles collected separately from virgin female and male midges were analyzed by gas chromatography (GC) coupled to mass spectrometry (MS) to reveal four female-specific components. In analyses by GC coupled to electroantennographic (EAG) recording from the antennae of a male midge, at least three of these components elicited responses. Based on its GC retention indices and mass spectrum, we propose that the major component is 2-acetoxy-5-undecanone and confirm this by synthesis of the racemic compound in seven steps and 63% yield from 4-pentenoic acid. The three minor components were each present at approximately 30% of the major component and were identified as 2-undecanone, (S)-2-acetoxyundecane, and (S)-2-undecanol by comparison of GC retention times and mass spectra with those of synthetic standards. GC analyses of the female-produced volatiles on an enantioselective column showed that only one enantiomer of 2-acetoxy-5-undecanone was present, and this was found to be the S-enantiomer by hydrolytic kinetic resolution of an epoxide intermediate in the synthesis and also by enantioselective hydrolysis of the racemic acetate with a lipase enzyme. The two enantiomers were also separated by high-performance liquid chromatography on an enantioselective column for field tests. In two field trapping tests, (S)-2-acetoxy-5-undecanone was highly attractive to male R. theobaldi; the R-enantiomer was not attractive. The racemic compound was just as attractive as the S-enantiomer, and addition of the three minor components in racemic form at two different loads did not affect catches. The pheromone could be dispensed from both rubber septa and polyethylene vials for at least 1 month under field conditions, but the former was preferred as it gave more uniform release. 2-Acetoxy-5-undecanone belongs to a new group of pheromone structures in the Cecidomyiidae, most others being mono- or diesters.  相似文献   
997.
    
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998.
999.
    
In response to stimulation with immobilized anti-CD3 antibody, splenocytes from C57BL/6 and BALB/c mice principally produced INF-gamma and IL-4, respectively. However, both splenocytes equally proliferated in response to ConA. We compared the changes after inoculation with BCG (1 mg/mouse) in their capacity to produce IL-4 or IFN-gamma in response to anti-CD3 antibody and to proliferate in response to ConA. Splenocytes from C57BL/6 and BALB/c mice, that had been inoculated with BCG 4 weeks before, produced IFN-gamma with diminished IL-4 production in response to anti-CD3 antibody. Furthermore these splenocytes became anergic to ConA stimulation and died due to cell apoptosis in stead of proliferation. However, we observed the strain difference at 12 weeks after BCG-infection. BCG-primed C57BL/6 splenocytes, that continuously produced IFN-gamma in response to anti-CD3 antibody, failed to proliferate in response to ConA. In contrast, BCG-primed BALB/c splenocytes, that increased IL-4 production but decreased IFN-gamma production when stimulated with anti-CD3 antibody, could proliferate well in response to ConA. Since the splenocytes of BALB/c mice became ConA responsive along with their shifting from Th1 dominant immune response at 4 weeks to Th2 dominant immune response at 12 weeks after BCG-inoculation, IL-4 was assumed to play a crucial role in activation of anergic T cells. Therefore, we stimulated splenocytes from both strains of mice infected with BCG 4 weeks before with ConA in the presence or absence of IL-4. Splenocytes from BCG-infected BALB/c mice showed marked proliferation, while those from BCG-infected C57BL/6 mice failed. We found that IL-4 protected against ConA-induced cell apoptosis in BALB/c splenocytes but not C57BL/6 splenocytes.  相似文献   
1000.
    
BACKGROUND: Erythromycin and its salts belong to the larger class of macrolides. Erythromycin is well tolerated. The most common side effects are gastrointestinal distress, nausea, and vomiting, which are dose related. Allergic and pseudoallergic reactions due to macrolide antibiotics are uncommon. Anaphylaxis and acute respiratory distress appear in the literature as case reports. METHODS: We report a 24-year-old man who presented 12 years ago a systemic allergic reaction to penicillin, confirmed by skin tests and detection of specific IgE (RAST). Since then he had tolerated erythromycin on several occasions. Nine months ago, his general practitioner prescribed erythromycin orally as treatment for a respiratory infection. Thirty minutes after taking the first dose, 500 mg, he developed an anaphylactic reaction. The episode subsided with treatment with high dose corticosteroids, antihistamines, and epinephrine. Skin prick tests and intradermal tests were performed with erythromycin at different concentrations. We also measured total IgE and specific IgE to erythromycin by CAP and Phadezym RAST (Pharmacia, Uppsala, Sweden), respectively. We also performed a Prausnitz-Küstner test (PK test), and oral challenge test. RESULTS: Skin testing to erythromycin was not helpful because of cutaneous hyperreactiviness. No significant levels of specific IgE to erythromycin were detected. The oral challenge and the Prausnitz-Küstner test were positive. CONCLUSIONS: The positive history and oral challenge test suggested an anaphylactic reaction to erythromycin. The positive Prausnitz-Küstner test demonstrated the presence of specific IgE to erythromycin.  相似文献   
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