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991.
Methanolic extracts of processed fruiting bodies of six edible mushroom species (Basidiomycota) - Armillaria mellea, Boletus badius, Boletus edulis, Cantharellus cibarius, Lactarius deliciosus collected from natural habitats and Pleurotus ostreatus of commercial origin - were analysed for the presence of non-hallucinogenic indole compounds. Thermal processing was designed in such a way that it mimicked conditions used for cooking of mushroom dishes, since only a narrow group of mushrooms can be eaten raw, while indole compounds are thermolabile. All processed extracts were shown to contain l-tryptophan (up to 8.92 mg/100 g dw). The contents of the remaining compounds, 5-methyltryptophan, tryptamine, melatonin, indoleacetonitrile and indole, varied in different species (from 0.71 to 6.55 mg/100 g dw). Extract of processed C. cibarius fruiting bodies contained l-tryptophan, 5-methyltryptophan, tryptamine, melatonin, indoleacetonitrile and indole (1.96-4.94 mg/100 g dw) whereas l-tryptophan (2.78 mg/100 g dw) and tryptamine (2.77 mg/100 g dw) were the only indole compounds identified in the processed fruiting bodies of A. mellea. 相似文献
992.
The reaction of CaO with CO(2) is a promising approach for separating CO(2) from hot flue gases. The main issue associated with the use of naturally occurring CaCO(3), that is, limestone, is the rapid decay of its CO(2) capture capacity over repeated cycles of carbonation and calcination. Interestingly, dolomite, a naturally occurring equimolar mixture of CaCO(3) and MgCO(3), possesses a CO(2) uptake that remains almost constant with cycle number. However, owing to the large quantity of MgCO(3) in dolomite, the total CO(2) uptake is comparatively small. Here, we report the development of a synthetic Ca-rich dolomite using a coprecipitation technique, which shows both a very high and a stable CO(2) uptake over repeated cycles of calcination and carbonation. To obtain such an excellent CO(2) uptake characteristic it was found to be crucial to mix the Ca(2+) and Mg(2+) on a molecular level, that is, within the crystalline lattice. For sorbents which were composed of mixtures of microscopic crystals of CaCO(3) and MgCO(3), a decay behavior similar to natural limestone was observed. After 15 cycles, the CO(2) uptake of the best sorbent was 0.51 g CO(2)/g sorbent exceeding the CO(2) uptake of limestone by almost 100%. 相似文献
993.
Marek Kociszewski Cezary Gozdecki Arnold Wilczyński Stanis?aw Zajchowski Jacek Mirowski 《Holz als Roh- und Werkstoff》2012,70(1-3):113-118
Wood-polyvinyl chloride (PVC) composites were prepared using industrial wood particles used for manufacturing three-layer particleboards. The effect of particle size (0.25–0.5, 0.5–1, 1–2, and 2–4?mm) on the mechanical properties of the composites was investigated. The effect of cross-section size (4×10, 6×15 and 8×20?mm2) of composite pieces made by an injection moulding method was also studied. Both the particle size and specimen cross-section area significantly influenced these properties. The tensile and flexural properties as well as the impact strength in general increased with increasing particle size, and decreased with increasing cross-section size. 相似文献
994.
Puppel K Nałecz-Tarwacka T Kuczyńska B Gołebiewski M Kordyasz M Grodzki H 《Journal of the science of food and agriculture》2012,92(12):2494-2499
BACKGROUND: So far, in research studies, the age of cows has not been considered as a factor that may influence the changes in the content of milk ingredients with antioxidant properties modified by the feed supplementation. The aim of this study was to determine the influence of supplementation on the content of ingredients having antioxidant properties and to determine the influence of the age of cows taking part in the experiment on these changes. The experiment was conducted using 20 Polish Holstein Friesian cows, 10 primiparous and 10 multiparous. The combined supplementation of fish oil and linseed constituted the experimental factor. RESULTS: The milk of primiparous cows after 21 days of supplementation was characterised by a higher content of C18:1 trans ‐11, C18:2 cis ‐9, trans ‐11, α‐retinol, α‐tocopherol and β‐lactoglobulin compared to the milk of multiparous cows, in which a higher level of lactoferrin, C20:5 and β‐carotene was recorded. In both groups an increase in the total antioxidant status was noted (a higher level in the milk of primiparous cows). CONCLUSIONS: Modification of the diet of cows with fish oil and linseed significantly influenced antioxidant properties of their milk; however, the response of multiparous and primaparous cows was noticeably different to the supplement introduced. Copyright © 2012 Society of Chemical Industry 相似文献
995.
以蔷薇果为研究对象,芦丁作为标准物质,采用不同的提取方法对蔷薇果中总黄酮进行分离制备。采用紫外见光分光光度法绘制标准曲线。在此基础上对6种提取物的吸光度进行了测定。根据实验结果确定了最佳提取方法。结果表明,提取温度80℃,提取溶剂80%乙醇,料液比1∶20(g/mL),提取时间240 min,作为最佳提取条件。在此条件下,蔷薇果中黄酮类化合物的提取率为1.897%。 相似文献
996.
Anton N. Sidorov Grzegorz W. Sławiński A.H. Jayatissa Francis P. Zamborini Gamini U. Sumanasekera 《Carbon》2012,50(2):699-705
We describe a simple method for decorating graphene (1–5 layers) with Au and Ag nanostructures (nanoparticles, nanorods, and nanoplates). We deposit graphene electrostatically from highly-oriented pyrolytic graphite onto Si/SiO2 surfaces functionalized with (aminopropyl)trimethoxysilane and grow the metal nanostructures by a seed-mediated growth method from hexanethiolate-coated Au monolayer-protected cluster “seeds” that are attached to graphene by hydrophobic interactions. Scanning electron microscopy reveals the selective growth of Au or Ag nanostructures on the graphene surface. In the case of Au, the low pH 2.8 growth solution causes etching of the graphene and formation of scroll-like structures. For Ag, the high pH 9.3 solution does not seem to affect the graphene. Raman spectroscopy is consistent with the graphene morphology and reveals that the presence of Au and Ag nanostructures increases the Raman scattering from the graphene by a factor of about 45 and 150, respectively. This work demonstrates a simple method for decorating graphene with noble metal nanostructures that may have interesting optical, electronic, and chemical properties for applications in nanoelectronics, sensing, and catalysis. 相似文献
997.
Stasiak-Ró?ańska Lidia B?a?ejak Stanis?aw 《European Food Research and Technology》2012,235(6):1125-1132
Dihydroxyacetone (1,3-dihydroxy-2-propanone, DHA) is applied in the food and cosmetic industries as well as in pharmacy and medicine. It is produced as a result of incomplete oxidation of glycerol by acetic acid bacteria Gluconobacter oxydans. This reaction is catalyzed by PQQ-dependent membrane-bound glycerol dehydrogenase. The research developed a method of obtaining DHA by oxidation of a 3?% aqueous solution of glycerol (pH 7.5) at a temperature of 23?°C, with the only reaction biocatalyst being an immobilized cell preparation obtained from G. oxydans cells. After 5?days of the process, DHA concentration in the solution accounted for 27.2?g/L and the reaction efficiency for 94?%. After 4?days of the reaction run in culture media with pH 5.0, at a temperature of 28?°C, free or immobilized cells of G. oxydans produced on average 25?g of DHA/L at the reaction efficiency of 87?%. 相似文献
998.
Heat treatments are very popular methods of food preparation in European countries. Phytosterol present in foodstuffs undergoes
oxidative changes during heat treatment, and phytosterol oxides (e.g., 7α-, 7β-hydroxysterol, 5α,6α-, 5β,6β-epoxysterol, 7-ketosterol
and triol) are formed. Phytosterol oxidation products (POPs) have been associated with cytotoxic and pro-apoptotic effects
in humans. On the other hand, several studies conducted on animals revealed that some phytosterol oxides lower serum triacyglycerol
and blood glucose levels. The aim of this study was to evaluate the effect of heat treatment on formation of phytosterol oxidation
products in selected foodstuffs. The following products were taken into considerations: minced meat (pork and beef), frozen
French fries, frozen fish fillets, frozen fish products (e.g., fish sticks), wheat and egg noodles. Sterols and POPs content
was evaluated by GC–MS working in total and selected ion monitoring modes. The phytosterol oxidation rate was higher in French
fries and fish fillets (0.20–1.69% of total phytosterol content) than in noodles, minced meats and readymade fish products
(in 0.04–0.36% range). Method of POPs determination using GC–MS is reported in this study. Results of this study show also
that products of the animal origin might be considered as sources of the phytosterol oxides in the human diet. 相似文献
999.
R.F. Szeloch P. Janus J. Serafińczuk P.M. Szecówka G. Jóźwiak 《Microelectronics Reliability》2012,52(4):711-717
Longitudinal performance and reliability of microelectronic structures is strongly influenced by the condition of interconnects. Degradation processes invoke changes, progressive in time, on the surface, in the body of interconnect layer, in the boundary between interconnect and the Si/SiO2 substrate, and in the area of substrate near Al line. Geometrical scale of these changes may vary in wide range, reaching nanometers. The authors investigate the condition of Al path of a fatigued commercial electronic circuit (memory), using in-house developed scanning thermal microscope (SThM) and commercial high resolution X-ray diffractometer (XRD). Series of SThM images were obtained for varying temperature of Wollaston probe working in active mode. The images, after processing by 2-dimensional spatial FFT, reveal various ingredients of the surface and internal structure of the Al line. FFT power spectrum dispersion is proposed as a measure of the amount of information available from the scan image. This measure may be used to determine the most efficient temperature of Wollaston probe. The result is a preliminary analysis of feasibility of the SThM approach for characterization of degradation process. In general SThM shall be perceived as a new technique for reliability analysis. 相似文献
1000.
Urolithiasis is a common diagnostic and therapeutic problem in small-animal veterinary practice. The traditional diagnostic approach usually consists of clinical, radiological and ultrasonographic examination of the patient. The main diagnostic material is still urine sediment, ignoring the fact that presence of crystalluria is not always of pathological significance. In order to establish the most effective therapeutic and preventative strategies, especially in the case of multicomponent stone, it is crucial to define the exact elemental composition of the given stone including crystallization nidus chemical contents. In the course of the research, the usefulness of scanning electron microscopy combined with X-ray-dispersive spectrometry in analysis of canine mixed and compound stones was investigated. The obtained results indicated that the tested method allows one to trace the dynamics of the crystallization process, including crystallization nucleus detection, and concurrently and quantitatively assess the elemental composition of the given urinary concrement. Moreover, the conducted research showed epidemiological data of urolithiasis occurrence in a population of dogs coming from the southern part of Poland. 相似文献