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31.
The cubic-tetragonal martensitic transition of V3Si and its precursor have been investigated in the temperature range from 13 K to 80 K using a 1 MV electron microscope with
a double-tilting cold stage. Below the transition temperature Tm = 19 K, fine twin lamellae appear parallel to {110} plane
traces, being connected continuously with mottled striations having the same orientation. Fine striations along {110} traces
or so-called tweeds are observed below 50 K at the precursor of the structural phase transition. The image contrast of mottled
striations and tweed patterns is attributed to the presence of lattice distortion owing to the softening of the shear modulus.
Reversible changes of the patterns recorded with a TV-VTR system during cooling and heating processes were discussed briefly.
This paper is based on a presentation made in the symposium “Pretransformation Behavior Related to Displacive Transformations
in Alloys” presented at the 1986 annual AIME meeting in New Orleans, March 2–6, 1986. under the auspices of the ASM-MSD Structures
Committee. 相似文献
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33.
The type and magnitude of urinary symptoms, the behavioral adjustments necessitated by such symptoms, and the degree of patient satisfaction with treatment and current health were evaluated in 102 men with symptomatic benign prostatic hyperplasia (BPH) who had been receiving finasteride for 9 to 12 months. We also evaluated these variables in a group of 109 men who had undergone transurethral resection of the prostate (TURP) for symptomatic BPH 9 to 12 months before the study. A validated, patient-directed telephone questionnaire was used to solicit information. Men with BPH who continued to receive finasteride therapy for at least 9 months experienced considerable symptomatic relief during the first year of therapy, and reported a high degree of satisfaction with their urinary condition. Urinary symptoms either resolved or occurred only rarely in the majority of men treated with finasteride. Most of the BPH patients taking finasteride (78%) indicated that urinary symptoms did not restrict their participation in normal activities. Fifty-four percent of finasteride patients rated their current health as excellent or very good, and 87% indicated that their current condition represented an improvement over their pretreatment state. Responses in the men treated with TURP reinforced previous observations about the effectiveness of this treatment in men with symptomatic BPH. Thus in the appropriate patient group, finasteride represents an effective management option for symptomatic BPH. 相似文献
34.
N Uchida T Ezaki S Hirabayashi A Minami H Fukuma H Matsuoka M Yachida K Kurokohchi SA Morshed M Nishioka M Matsuoka T Nakatsu 《Canadian Metallurgical Quarterly》1997,92(9):1440-1443
OBJECTIVE: In 21 patients, our objective was the endoscopic removal of common bile duct stones by sphincter dilation with the application of sublingual nitroglycerin. METHODS: Nitroglycerin 0.3-0.6 mg was needed for proper dilation of the orifice and for successful cannulation of the Dormia basket into the bile duct. Cannulation of the Dormia basket was simplified by placing the guidewire in the common bile duct beforehand. Because of possible stone impaction, a mechanical lithotriptor was applied smoothly in two patients. RESULTS: Complete stone removal was successful in 18 of the 21 (86%) patients. One patient who developed a mild form of acute pancreatitis recovered in a few days by conservative management with drip infusion of protease inhibitor. Blood pressure dropped transiently in a patient receiving nitroglycerin, but the general condition of the patient was stable. CONCLUSIONS: This procedure was found to be safe, easy, and effective in extracting common bile duct stones. 相似文献
35.
36.
A series of resol-type phenol-formaldehyde resins with varying phenol/formaldehyde (P/F) molar ratio were investigated by infrared spectroscopy. The infrared spectroscopic data suggest that absorbance ratio of D2920, D1610, D1150, D1010, and D760 based on 1 590 cm?1 band can be used for the determination of phenol/formaldehyde molar ratio of the resins. 相似文献
37.
Recent development of superconducting accelerator dipole magnets in Japan is described. A series of NbTi/Cu dipoles in the region of 5 to 10 T is being developed at KEK. The maximum field will depend on the maximum proton energy of the TRISTAN ring from 300 to 600 GeV. On the other hand, development of a special Nb3 Sn/Cu dipole magnet in the region of 10 T has been started for the future multi-TeV pp andbar{p}p colliding beam accelerator. 相似文献
38.
We have improved the sonic spray interface to enable the analysis of multiply charged ions of protein from a solution at a flow rate of 1 mL/min using a conventional liquid chromatograph/mass spectrometer. In this interface, we added a multihole plate in front of the sampling orifice of a mass spectrometer. This plate does not have a hole coaxial to the sampling orifice but has small holes around the central region of the plate. The plate reduces the density of the solvent molecules in the sprayed gas introduced into the vacuum region through the sampling orifice from the atmosphere and prevents the ions from being solvated and becoming charged droplets due to the cooling that follows adiabatic expansion of the sprayed gas. With this improvement, multiply charged ions whose charge distribution ranged from 11+ to 16+ were analyzed from a 1 μM cytochrome c solution at a high flow rate of 1 mL/min without using a splitter. 相似文献
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40.
Yamamoto N Muramoto A Yoshinaga J Shibata K Endo M Endo O Hirabayashi M Tanabe K Goto S Yoneda M Shibata Y 《Environmental science & technology》2007,41(18):6357-6362
We compared the status of carbonaceous aerosols in Tokyo before and after the implementation of a diesel vehicle regulation intended to reduce the quantity of particulate carbon from diesel engines in one of the largest scale ever attempts at vehicle exhaust control. Radiocarbon (14C) in elemental carbon (EC) and total carbon (TC) were analyzed to identify fossil fuel carbonaceous particles emitted from diesel-powered vehicles. One-sided paired-month t-tests showed no distinct difference in the absolute concentrations of particles in terms of total mass (19.5 to 18.0 microg m(-3); p = 0.321), EC (3.6 to 3.3 microg m(-3); p = 0.272), and TC (6.3 to 6.2 microg m(-3); p = 0.418) for the finest particles (d(a) < 1.1 microm) after the implementation of the regulation. The ratios of the concentrations of the chemical constituents were, however, altered after the regulation. EC/TC was significantly decreased from 56.7% to 50.2% (p = 0.039). Although it was not statistically significant, the percentage of fossil carbon in EC also decreased (67.8% to 63.8%; p = 0.104). Since EC is predominantly of combustion origin, the observed decrease was likely due to the decrease in fossil EC emissions from diesel-powered vehicles. The decrease in EC/TC after the implementation of the regulation was also likely to have resulted from attachment to diesel vehicle exhaust systems of particulate filters as required as part of the regulation by the Tokyo Metropolitan Government. The EC/TC of fossil carbon of the finest particles decreased from 66.2% to 55.2% (p = 0.066), but EC/TC of biomass carbon did not decrease but rose slightly from 43.6% to 44.5% (p > 0.5). Thus, the relative ratios of components of carbonaceous aerosol particles, such as 14C, could provide a better understanding of the atmospheric pollution status, despite short-term fluctuations, than do measurements of absolute concentrations. 相似文献