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101.
Compared the MMPI performances of 15 male dysphasic brain-damaged adults with the performances of 15 matched control brain-damaged Ss without specific language impairment. A significant overall difference on the 9 clinical scales combined was shown by multivariate analysis, with higher scores obtained by dysphasic Ss. Further univariate analysis showed significantly higher scores on the Pd and Sc scales. Results are discussed in terms of (a) evidence for a closer relation between MMPI variables and behavioral measures than between MMPI variables and neurological measures of lesion laterality, and (b) the interpretive limitations implied by uncritical transference of MMPI findings based on psychiatric patients and normals to patients with central nervous system lesions. The need for validation studies investigating social behavior correlates of MMPI results in brain-damaged samples is emphasized. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
103.
Magnetic filtration effectively removed bacteriophage T7 from water. The removal was undertaken by adsorbing the virus onto magnetite in the presence of calcium chloride and by passing the mixture through a filter placed in a magnetic field. 相似文献
104.
Schellenberger EA Weissleder R Josephson L 《Chembiochem : a European journal of chemical biology》2004,5(3):271-274
The many uses of chemically modified annexin Vs necessitate an understanding of the optimal degree of modification and modification sites of the protein. When reacted with the N-hydroxysuccinimide ester of Cy5.5, annexin V with one modification per mole of protein retained its affinity for phosphatidylserine of apoptotic cells, whereas modification with two dyes per mole of protein caused a complete loss of activity. A tryptic digest LC/MS method was used to identify the modification sites as either of two closely spaced lysine residues, in position 286 or 290. The crystal structure indicated the location of these lysines was distal to the phosphatidylserine binding sites on annexin V. These results can be used to develop active or inactive fluorescent control annexin V proteins and to suggest strategies for attaining higher levels of modification with retention of bioactivity. 相似文献
105.
Estimation of safe exposure time from an ophthalmic operating microscope with regard to ultraviolet radiation and blue-light hazards to the eye 总被引:2,自引:0,他引:2
Michael R Wegener A 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(8):1388-1392
Hazards from the optical radiation of an operating microscope that cause damage at the corneal, lenticular, and retinal levels were investigated; we considered, in particular, ultraviolet radiation (UVR) and blue light. The spectral irradiance from a Zeiss operation microscope OPMI VISU 200 was measured in the corneal plane between 300 and 1100 nm. Effective irradiance and radiance were calculated with relative spectral effectiveness data from the American Conference for Governmental and Industrial Hygienists. Safe exposure time to avoid UVR injury to the lens and cornea was found to be 2 h without a filter, 4 h with a UVR filter, 200 a yellow filter, and 400 h with a filter combination. Safe exposure time to avoid retinal photochemical injury was found to be 3 min without a filter and with a UVR filter, 10 min with a yellow filter, and 49 min with a filter combination. The effective radiance limit for retinal thermal injury was not exceeded. The hazard due to the UVR component from the operating microscope is not critical, and operation time can be safely prolonged with the use of appropriate filters. The retinal photochemical hazard appears critical without appropriate filters, permitting only some minutes of safe exposure time. The calculated safe exposure times are for worst-case conditions and maximal light output and include a safety factor. 相似文献
106.
Appearance-based face recognition and light-fields 总被引:7,自引:0,他引:7
Gross R Matthews I Baker S 《IEEE transactions on pattern analysis and machine intelligence》2004,26(4):449-465
Arguably the most important decision to be made when developing an object recognition algorithm is selecting the scene measurements or features on which to base the algorithm. In appearance-based object recognition, the features are chosen to be the pixel intensity values in an image of the object. These pixel intensities correspond directly to the radiance of light emitted from the object along certain rays in space. The set of all such radiance values over all possible rays is known as the plenoptic function or light-field. In this paper, we develop a theory of appearance-based object recognition from light-fields. This theory leads directly to an algorithm for face recognition across pose that uses as many images of the face as are available, from one upwards. All of the pixels, whichever image they come from, are treated equally and used to estimate the (eigen) light-field of the object. The eigen light-field is then used as the set of features on which to base recognition, analogously to how the pixel intensities are used in appearance-based face and object recognition. 相似文献
107.
Determination of methionine and selenomethionine in yeast by species-specific isotope dilution GC/MS
A method for the simultaneous determination of methionine (Met) and selenomethionine (SeMet) in yeast using species-specific isotope dilution (ID) gas chromatography/mass spectrometry (GC/MS) is described. Samples were digested by refluxing for 16 h with 4 M methanesulfonic acid. Analytes were derivatized with methyl chloroformate and extracted into chloroform for GC/MS analysis. In addition to use of commercially available 13C-enriched Met and SeMet spikes for species specific ID analysis, a 74Se-enriched SeMet spike was also available for comparison of results. In selective ion monitoring mode, the intensities of ions at m/z 221, 222, 269, 270, and 263 were used to calculate the 221/222, 269/270, and 269/263 ion ratios for quantification of Met and SeMet. Concentrations of 5959 +/- 33 and 3404 +/- 12 microg g(-1) (one standard deviation, n = 6) with relative standard deviations of 0.55 and 0.36% for Met and SeMet, respectively, were obtained using 13C-enriched spikes. A concentration of 3417 +/- 8 microg g(-1) (one standard deviation, n = 6) was obtained using the 74Se-enriched SeMet spike. The concentration of SeMet measured in the yeast is equivalent to 66.43 +/- 0.24% of total Se and 30.31 +/- 0.11% of total Met is in the form of SeMet. Method detection limits (three times the standard deviation) of 3.4 and 1.0 microg g(-1) were estimated for Met and SeMet, respectively, based on a 0.25-g subsample of yeast with 1 mL of extract used for derivatization. A similar concentration of 5930 +/- 29 microg g(-1) (one standard deviation, n = 4) for Met and a lower concentration of 2787 +/- 49 microg g(-1) (one standard deviation, n = 4) for SeMet were obtained for this yeast sample using species-specific ID analysis based on GC/MS with 13C-enriched Met and SeMet spikes when a 2-h open microwave digestion approach using 8 M methanesulfonic acid was used. 相似文献
108.
Thomas RH 《Radiation protection dosimetry》2004,109(4):277-289
The International Commission on Radiological Protection (ICRP) is now reviewing its recommendations with a view to publishing their revision in 2005. The last set of recommendations issued by the ICRP has caused some concern to neutron dosimetrists. This paper attempts to explain these concerns. Technological developments make it likely that exposure to high-linear energy transfer (LET) radiations will increase in the future. It is in the area of the dosimetry of high-LET radiations, particularly neutrons, where some experts feel that ICRP recommendations have been unclear. This paper discusses the process of setting protection limits in toxicology and its application to radiation protection. The development of radiation protection quantities and models is described, and the problems found with effective dose described. Suggestions for improvements are made that would enable effective dose to serve in two modes--both as a limiting quantity and also as the measurable (operational) quantity required by dosimetrists. 相似文献
109.
Suggests guidelines for developing evaluative procedures to fit the needs and constraints of specific treatment settings. The orientation is practical, recognizing that clients and professionals alike must carefully attend to cost–benefit factors. It is felt that psychotherapists can move beyond their current impressionistic, global evaluations and develop procedures with greater value for corrective feedback and communication to both lay and professional audiences. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
The uptake of selected steroids and norsesquiterpenes by live minnows,Pimephales promelas, was studied when the compounds were administered externally in aqueous solution. The gills of minnows absorbed 80% of the steroid removed from solution. Steroid absorption across minnow gills is apparently a nonmediated process as rate saturation could not be demonstrated. Initial absorption rates of test compounds were inversely correlated with (1) the degree of oxygenation, (2) water solubility, and (3) polarity on silica gel thin-layer chromatography. These findings support the Stein model of non-mediated transport. The majority of compounds anesthetic and toxic to minnows exerted their effects at a similar internal concentration. Anesthesia occurred at ca. 10–6–10–5 M and death at 10–4–10–3 M. Since various agents causing membrane stabilization and lysis in in vitro systems act in an identical concentration range, it is proposed that the defensive steroids and norsesquiterpenes of water beetles act via membrane stabilization and lysis. 相似文献