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排序方式: 共有224条查询结果,搜索用时 12 毫秒
41.
Applied Intelligence - In the present study, we present an intelligent earthquake signal detector that provides added assistance to automate traditional disaster responses. To effectively respond...  相似文献   
42.
Sudo  Yui  Itoyama  Katsutoshi  Nishida  Kenji  Nakadai  Kazuhiro 《Applied Intelligence》2021,51(11):8245-8259
Applied Intelligence - This paper proposes a multichannel environmental sound segmentation method. Environmental sound segmentation is an integrated method to achieve sound source localization,...  相似文献   
43.
Homogeneous and stoichiometric crystalline LiNbO3 fibers were successfully prepared above 450°C by sol-gel processing with metal alkoxides. Controlling the concentration of alkoxide solution and the amount of water used for partial hydrolysis made it possible to draw gel fibers having uniform diameters (10 to 100 μm) from the metal alkoxide solution. The gel fibers withdrawn crystallized directly to single-phase LiNbO3 fibers by heating from 450° to 600°C. The density of the crystalline LiNbO3 fibers was higher than 4.22 g/cm3, and the dielectric constant at room temperature was about 10 at 10 MHz.  相似文献   
44.
Cross-section images of MeV energy X-ray CT have been simulated with the Monte Carlo method taking into account the flux and energy spectrum of the photons emitted from the X-ray sources. The simulation reveals the theoretical limit of the performance of MeV energy CT systems. The simulated attenuation characteristics, signal-to-noise ratio and the modulation transfer function of the simulated images agree well with the experimental ones, showing the validity of the calculations. The simulation technique allows the image quality of an arbitrary object to be checked with an arbitrary energy source in advance. One of the example simulations presented shows that the CT systems have a theoretical capability to discriminate a density difference of 2–3% in the rotate-only mode as long as the size of an object is within the penetration capability of the X-ray source.  相似文献   
45.
The extraction equilibrium of mercury(II) from aqueous ammonium thiocyanate solution with triisobutyl-phosphine sulfide(=TIBPS=S¯) in toluene has been measured at 303 K. It was found that mercury(II) is extracted according to a solvation reaction by TIBPS as a mercurydl) :TIBPS 1:2 complex, Hg(SCN)2S2, as follows:

The extraction equilibrium constant, Ke, was evaluated as Ke = 1.8 × 106 (dm3/mol)2.  相似文献   
46.
Distribution equilibria of lead(II) in the extraction with di(2-ethylhexyl)phosphoric acid and 2-ethylhexyl 2-ethylhexylphosphonic acid in toluene from aqueous ammonium nitrate solutions were measured at 303 K to elucidate the concentration dependencies of the reactant species on the distribution ratio. It was found that lead(II) is extracted as the mononuclear complex, PbR22HR, with the former extrac-tant while it is extracted not only as the complex, PbR22HR, but also as the complex, Pb(NO3)R;HR, accompanied by simultaneous transfer of nitrate anion with the latter ex-tractant. The extraction equilibrium constants of these complexes were evaluated as well as the stability constants of lead(II) -nitrato complexes, Pb(NO3)+, Pb(NO3)2and Pb(NO3)? 3.  相似文献   
47.
A biomass waste of microalgae was chemically modified by immobilizing the functional group of polyethyleneimine to prepare a new type of adsorbent. The adsorption test revealed that this adsorbent exhibited remarkably high selectivity for Pd(II) and Pt(IV) over base metal ions in HCl solution. From the adsorption isotherm, its maximum adsorption capacity for Pd(II) and Pt(IV) was evaluated as 2.0 and 0.8 mmol/g, respectively. This adsorbent also exhibited high affinity and selectivity for Pd(II) and Pt(IV) even in the presence of high concentrations of base metals in actual leach liquor.  相似文献   
48.
Novel, anionic surface-active monomers, sodium di(10-undecenyl)sulphosuccinate (DUSS) and sodium n-undecyl 10-undecenylsulphosuccinate (MUSS) were prepared. The monomers were soluble in both water and apolar organic solvents on heating. DUSS and MUSS in water exhibited Kraft points at about 39°C and 48°C, respectively. The critical micelle concentrations for aqueous solutions of DUSS and MUSS at 50°C were determined to be 2.4 × 10−5 and 1.2 × 10−5 mol l−1, respectively. Polymerization of the monomers in darkness and under u.v. irradiation at 50°C were studied using three different solvents, namely water, n-hexane and dioxane, giving aqueous micelles (or vesicles), reversed micelles and isotropic solution, respectively. Only traces of polymers were formed for the polymerizations in darkness, while the polymerizations under u.v. irradiation gave polymers, except for the polymerization of MUSS in dioxane. The solvents used for the polymerization were observed to exert an effect on the solubility of the polymers of DUSS and only the polymer obtained from the polymerization in water was soluble in solvents such as water and N,N-dimethylformamide. Thus, the monomer aggregation, especially for the aqueous system, was found to affect the structure of the resulting polymers.  相似文献   
49.
Interleukin-2 (IL-2) is a potent activator of cellular immunityand has been utilized as an immunotherapeutic agent. We stablyimmobilized human IL-2 to collagen by covalently binding itto the N-terminus of human type III collagen (3A1) as IL2-3A1chimeric protein using recombinant technology. The present studywas aimed at liberating IL-2 from the immobilized chimeric proteinby treating the chimera with bacterial collagenase. These IL2-3A1chimeras were synthesized in insect cells which had been infectedwith baculovirus vectors carrying IL2-3A1 cDNA. The IL2-3A1protein produced was shown to be in a pepsin-resistant triplehelical structure and exhibited IL-2 activity to a similar extentas IL-2 itself. IL2-3A1 could be immobilized on the surfaceof plastic dishes by incubating it in the dishes. The IL-2 regionof the immobilized IL2-3A1 was liberated to culture media bycollagenase treatment and this freed IL-2 stimulated the growthof lined T cells. Thus, IL2-3A1 chimeric protein could be utilizedas an IL-2 deliverer whose T cell mitogenic activity can beliberated by a collagenolytic environment.  相似文献   
50.
BACKGROUND: This research provides a new approach to the effective use of microalgal biomass waste generated by biofuel conversion processes. In this study, a novel adsorbent for Au(III) recovery was prepared by treating microalgal residues with concentrated sulfuric acid. RESULTS: The prepared adsorbent, crosslinked microalgae, exhibited high affinity and selectivity for Au(III) over other precious and base metal ions in a hydrochloric acid medium. From the adsorption isotherms, the maximum adsorption capacity of the crosslinked microalgae for Au(III) was estimated to be 3.25 mol kg?1 (640 g kg?1), which was about eight times higher than the adsorption capacity of the microalgal residue. Microphotographs, scanning electron microscopy, and X‐ray diffraction confirmed the formation of metallic Au, suggesting that a redox reaction had taken place between the adsorbent and Au(III) ions during adsorption. Comparison of Fourier‐transform infrared spectra before and after adsorption indicated that hydroxyl groups as well as ether oxygen atoms in the crosslinked microalgae participated in the Au(III) uptake mechanism. It also suggested that the reduction of Au(III) to Au(0) was facilitated by hydroxyl groups in the crosslinked microalgae. CONCLUSION: The results presented in this paper are very promising for the practical use of microalgal residues for the recovery of Au(III) because of good selectivity and favorable adsorption capacity for Au(III). Copyright © 2011 Society of Chemical Industry  相似文献   
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