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131.
Genetic algorithms (GAs) are search procedures for combinatorial optimization problems. Because GAs are based on multipoint search and use the crossover operator, they have an excellent global search ability. However, GAs are not effective for searching the solution space locally due to crossover-based search, and the diversity of the population sometimes decreases rapidly. In order to overcome these drawbacks, we propose a new algorithm called immunity-based GA (IGA), combining features of the immune system with GAs. IGA is expected to improve the local search ability of GAs and to maintain the diversity of the population. We apply IGA to the VLSI floor-plan design problem. Experimental results show that IGA performs better than GAs. 相似文献
132.
Koji Ouchi Akihiko Mikami Hironori Itoh Masataka Makebe 《Fuel Processing Technology》1985,11(3):231-240
Yubari coal vitrite was extracted with quinoline at 420° C for 0–4 h and the products were separated into several fractions. Quinoline solubles (QS) and insolubles (QI) increased with time and the total recovered weight became nearly 200% of the original weight of the coal. A large part of this weight increase was due to the contribution of the formation of biquinoline and to quinoline addition to coal. Depolymerization to smaller molecules and polymerization to QI took place simultaneously via the addition of quinoline and the production of biquinoline. 相似文献
133.
Hironori Oda 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1988,41(4):287-295
The photofading behaviour of Crystal Violet Lactone was investigated in solution. The contribution of singlet oxygen to that fading was suggested. UV absorbers containing nickel sulphonate quenching groups were prepared and the protecting effect of these compounds towards the photofading of colour materials derived from colour formers was examined in solution and in solid state. It was proposed that nickel salts of 2,2′-dihydroxy-4,4′-dimethoxybenzophenone-5-sulphonic acid and its derivative can be applied as effective stabilisers against the photofading of indicator dyes in pressure (or heat) sensitive recording systems. 相似文献
134.
Hironori Yamazoe Kiyoshi Yamauchi Toshizumi Tanabe 《Materials science & engineering. C, Materials for biological applications》2009,29(4):1105-1108
Recently, large-scale production of the pharmaceutical grade recombinant human serum albumin was achieved, and several clinical trials have proved its safety and efficacy. Albumin is thought to be a candidate for a safe biopolymer sources for application to biomaterials. In this study, we treated albumin with sodium sulfite and sodium tetrathionate to give S-sulfo albumin, which was found to loose native albumin structure by CD spectra analysis and dye-binding assay. A water-insoluble S-sulfo albumin films were prepared by drying S-sulfo albumin solution and subsequent reformation of disulfide bonds by the oxidation with iodine. Ultimate strength, ultimate elongation and Young's modulus of S-sulfo albumin film prepared at room temperature were 3.3 ± 0.4 MPa, 30.8 ± 3.2% and 40.8 ± 3.3 MPa before oxidative treatment and changed to 13.8 ± 4.2 MPa, 5.6 ± 2.8% and 401.7 ± 15.3 MPa after oxidative treatment. When the film was prepared at 60 °C, similar tendency was observed. Thus, the disulfide bonds formation between albumin molecules by oxidative treatment converted the film stronger and stiffer. Cell adhesion and proliferation on the films were evaluated using mouse L929 fibroblast cells. Cell adhesion largely depended on the albumin structure; that is, cells did not attach to native albumin coated surfaces, while cell adhesion and proliferation occurred on the S-sulfo albumin films which lost their native albumin structure. Eighty percent of seeded cells were adhered on S-sulfo albumin films and proliferated well in a similar manner to those on the conventional culture dish. Our results indicate that S-sulfo albumin is a favorable cell culture substrate. 相似文献
135.
Removal of calcium and magnesium ions in a salt solution with the macroreticular chelating resin containing aminomethylphosphonic acid groups was investigated. The resin (RMT-P) exhibited high affinity for calcium and magnesium ions in a salt solution containing 200 g/dm3 of sodium chloride. In the column method, calcium and magnesium ions in a salt solution were preferentially absorbed on the RMT-P, when the salt solution containing 100 mg/dm3 of calcium or magnesium ion was passed through the RMT-P column at a space velocity of 15 h?1. The calcium and magnesium ions adsorbed were eluted by allowing 1 mol/dm3 hydrochloric acid to pass through the column. The recycle of adsorption and elution was found to be satisfactory. 相似文献
136.
Japanese Taiheiyo coal (75.9%C) was oxidized with air at 250 °C for 3–40 h and at 300 °C for 3–10 h. The weight decreased from 16.3 to 46.5% at 250 °C and from 21.7 to 41.3% at 300 °C. Carbon loss and yield of NaOH soluble were obtained. The resultant oxidation products were hydrogenated at 370 °C for 1 h under 10 MPa hydrogen pressure using red mud with sulphur as catalyst and wash oil as solvent. Conversion to pyridine, benzene and n-hexane soluble fraction shows a minimum for the coal oxidized 10 h at 250 °C and for the coal oxidized for 3 h at 300 °C. Initial oxidation makes a network structure which contributes to a reduction in conversion, but in later stages of oxidation, splitting of bridge linkages and/or ring opening of aromatic structures, contribute to increases in conversion. 相似文献
137.
DE Kuhl S Minoshima JA Fessler KA Frey NL Foster EP Ficaro DM Wieland RA Koeppe 《Canadian Metallurgical Quarterly》1996,40(3):399-410
To map presynaptic cholinergic terminal densities in normal aging (n = 36), Alzheimer's disease (AD) (n = 22), and Parkinson's disease (PD) (n = 15), we performed single-photon emission computed tomography using [123I]iodobenzovesamicol (IBVM), an in vivo marker of the vesicular acetylcholine transporter. We used coregistered positron emission tomography with [18F]fluorodeoxyglucose for metabolic assessment and coregistered magnetic resonance imaging for atrophy assessment. In controls (age, 22-91 years), cortical IBVM binding declined only 3.7% per decade. In AD, cortical binding correlated inversely with dementia severity. In mild dementia, binding differed according to age of onset, but metabolism did not. With an onset age of less than 65 years, binding was reduced severely throughout the entire cerebral cortex and hippocampus (about 30%), but with an onset age of 65 years or more, binding reductions were restricted to temporal cortex and hippocampus. In PD without dementia, binding was reduced only in parietal and occipital cortex, but demented PD subjects had extensive cortical binding decreases similar to early-onset AD. We conclude that cholinergic neuron integrity can be monitored in living AD and PD patients, and that it is not so devastated in vivo as suggested by postmortem choline acetyltransferase activity (50-80%). 相似文献
138.
During the course of our research into the use of cane by-products from sugar manufacturing, we have studied the isolation and structural determination of bioactive compounds present in sugarcane molasses. In this study, dehydrodiconiferylalcohol-9'-O-beta-D-glucopyranoside (1) and isoorientin-7, 3'-O-dimethyl ether (2) were isolated as antibacterial active compounds against cariogenic bacteria. Their structures were elucidated by (1)H-NMR, (13)C-NMR and ESI-MS. The activities of these isolated compounds against Streptococcus mutans and Streptococcus sobrinus were assessed by a minimum inhibitory concentration (MIC) test. The MICs of compounds 1 and 2 against both S. mutans and S. sobrinus were >4 mg/mL and 4 mg/mL, respectively. 相似文献
139.
Paul Smith Tanaka Shiori Hironori Hondoh Joël Wallecan Satoru Ueno 《Journal of the American Oil Chemists' Society》2022,99(8):665-674
There has been much work on polymorphism and crystal habit of quiescently crystallized palm oil. However, researchers have found it difficult to probe the process of sheared crystallization. The effect of surface-active molecules as nucleation agents or habit modifiers was demonstrated in quiescent systems. The aim of this work is to explore the effects of shear and specific lecithins (soy and sunflower) on palm oil crystallization by monitoring crystallization under shear using a synchrotron radiation source, as well as microscopy and DSC. It was found that increasing shear led to increasing β′ stabilization in all situations. Soybean lecithin had little effect on behavior. Sunflower lecithin led to even greater β′ stabilization. The different lecithins interact with the crystallizing fat changing rates of nucleation and crystal growth. Thus, the structure of the overall system can be dramatically altered. Microscopy revealed very different structures even if the polymorphism of the different systems was similar. Consequently, specific interactions can be manipulated in order to control the system. In particular, control of lecithin composition affects the stability of the different polymorphs. Palm oil crystallization under realistic processing conditions has been characterized. Under these conditions, increasing shear rates give higher β′ stability. Specific lecithins have different effects. In particular, soybean lecithin is β′ stabilizing, whereas sunflower lecithin has limited effects. Thus the overall structure of lecithin is important in determining the efficacy. This can be applied to control the structure and properties of different systems such as shortenings or spreads where crystalline interactions create the macro-structure that determines product properties. 相似文献
140.
Constrained optimization using a multipoint type chaotic Lagrangian method with a coupling structure
This article proposes a new constrained optimization method using a multipoint type chaotic Lagrangian method that utilizes chaotic search trajectories generated by Lagrangian gradient dynamics with a coupling structure. In the proposed method, multiple search points autonomously implement global search using the chaotic search trajectory generated by the coupled Lagrangian gradient dynamics. These points are advected to elite points (which are chosen by considering their objective function values and their feasibility) by the coupling in order to explore promising regions intensively. In this way, the proposed method successfully provides diversification and intensification for constrained optimization problems. The effectiveness of the proposed method is confirmed through application to various types of benchmark problem, including the coil spring design problem, the benchmark problems used in the special session on constrained real parameter optimization in CEC2006, and a high-dimensional and multi-peaked constrained optimization problem. 相似文献