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161.
Oilseeds are important sources of edible proteins. Their varieties varied in oil and protein content; sesame and rapeseeds had the highest oil content, but soybean and glandless cottonseeds had the highest protein content. Foaming properties of oilseed proteins are important for the domestic market to be used in the preparation of various food products. Whole rapeseed had the highest foam capacity followed by soybean, sunflower, safflower, glandless cottonseed, peanut and finally sesame. The extraction of lipids from oilseeds caused a significant improvement in their foam capacity and foam stability. High positive correlation was found between soluble proteins and foam capacity of oilseeds. The foam capacity was high at pH 7, and decreased below it reaching a minimum at pH 4. The foam stability also varied with pH; being maximum at the isoelectric point and minimum at pH 7. The foam capacity of oilseed protein isolates decreased with the prolongation of heating time at 100 °C. 相似文献
162.
Marwa A. A. Mohamed Azza El‐Maghraby Mona Abd El‐Latif Hassan Farag Kyriaki Kalaitzidou 《Polymer Composites》2014,35(12):2343-2352
The focus of this study is to improve the dispersion state of nanocrystalline (nc) Fe‐Ni particles in polyamide 6 (PA6) matrix and the filler‐matrix interfacial interactions to provide Fe‐Ni alloy/PA6 nanocomposites of remarkable mechanical performance for engineering applications. nc Fe40Ni60 particles were chemically synthesized. Then Fe40Ni60/PA6 nanocomposites of various nanofiller loading were prepared by compounding via a newly modified master batch technique called ultrasound assisted master batch (UMB), followed by injection molding (IM). Their mechanical properties, morphology and structural parameters were characterized and compared with the corresponding properties of Fe40Ni60/PA6 nanocomposites made by solution mixing (SM) and IM. The study reveals that the UMB process is more cost effective and time efficient, simpler and easier to scale up compared with the SM process. In addition, UMB nanocomposites exhibit superior mechanical properties and distinctive morphology compared with the corresponding SM ones. Moreover, structural analyses indicate that physical structural changes occurred in PA6 due to presence of alloy particles are affected differently by the different compounding methods, profound understanding of such phenomenon is focused throughout the article. These distinctive advantages recommend that UMB technique can be of great potential in commercial production of polymer nanocomposites (PNCs). It is concluded that the sonication of nc Fe40Ni60 particles in dilute polymer solution during UMB compounding, a new step that is incorporated for the first time in the master batch process, is mainly responsible for the good wetting between nanoparticles and polymer chains, strong filler‐matrix interactions and consequently the remarkable mechanical performance of UMB PNCs. POLYM. COMPOS., 35:2343–2352, 2014. © 2014 Society of Plastics Engineers 相似文献
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164.
Youssuf A. Gherbawy Ismail M. Shalaby Mahmoud Syed Abd El-sadek Hesham M. Elhariry AbdelElah A. Banaja 《International journal of molecular sciences》2013,14(11):21887-21898
Recently, new strains of Fasciola demonstrated drug resistance, which increased the need for new drugs or improvement of the present drugs. Nanotechnology is expected to open some new opportunities to fight and prevent diseases using an atomic scale tailoring of materials. The ability to uncover the structure and function of biosystems at the nanoscale, stimulates research leading to improvement in biology, biotechnology, medicine and healthcare. The size of nanomaterials is similar to that of most biological molecules and structures; therefore, nanomaterials can be useful for both in vivo and in vitro biomedical research and applications. Therefore, this work aimed to isolate fungal strains from Taif soil samples, which have the ability to synthesize silver nanoparticles. The fungus Trichoderma harzianum, when challenged with silver nitrate solution, accumulated silver nanoparticles (AgNBs) on the surface of its cell wall in 72 h. These nanoparticles, dislodged by ultrasonication, showed an absorption peak at 420 nm in a UV-visible spectrum, corresponding to the plasmon resonance of silver nanoparticles. The transmission electron micrographs of dislodged nanoparticles in aqueous solution showed the production of reasonably monodisperse silver nanoparticles (average particle size: 4.66 nm) by the fungus. The percentage of non hatching eggs treated with the Triclabendazole drug was 69.67%, while this percentage increased to 89.67% in combination with drug and AgNPs. 相似文献
165.
Alkaline and acidic media have been used in the textile dye industry, depending on the fabric nature. The bioremoval of textile direct violet dye by Aspergillus niger fungal strain was studied. The effect of pH on dye bioremoval was investigated at a pH range from 2 to 11. The direct violet dye bioremoval reached maximum with 92.4%, 64.0%, 91.4%, and 62.3 % at pH values of 2, 3, 8, and 9, respectively, at 24 h of incubation. The percentages of removal rate after 72 h incubation were 98.9, 97.3, 94.0, 95.0, 97.0, and 97.3 at pH 2, 3, 6, 7, 8, and 9, respectively. The optimum pH values were 2, 3, 8, and 9 for direct dye removal. At the end of the experiments, the treatment with fungal strain could reduce COD value of synthetic dye solution by 76-91%. Pseudo first and second order kinetic models were applied to evaluate differences in the biosorption rates and uptakes of textile dye. Pre-equilibrium biosorption of direct violet dye onto fungus under different dye concentrations followed a pseudo second order kinetic model with a high degree of correlation coefficients (R2 > 0.99), and the calculated values of qe nearly matched the experimental values of textile dye during the biotreatment process. 相似文献
166.
C. Yahaya M. S. Abd Latiff A. B. Mohamed 《International Journal of Communication Systems》2013,26(3):315-336
The exact contribution of this paper is a review of existing state‐of‐the‐art routing strategies for optical burst switched networks developed by researchers to deal with burst contention before it happens. Routing schemes are implemented in space domain, which make them simple and cost effective. Additionally, the paper points out the importance of routing as an effective way to deal with burst contention compared to other solutions. It also underlines the main differences between contention avoidance schemes and contention resolution techniques for optical burst switched networks. We believe that this review will help different optical burst switched researchers involved in the development of route optimization algorithms to control burst contention. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
167.
168.
Mohamed Emam Abd El-Razek 《Canadian Metallurgical Quarterly》1999,125(4):233-241
Diaphragm walls are built to exclude earth and water from an area so that work may be performed under reasonably dry conditions. The range of applications for diaphragm walls includes earth-retaining and load-bearing walls for a variety of constructs such as underpasses, deep basements, underground stations, tunnels docks, and pump houses. In traditional construction methods, the concrete diaphragm wall consists of separate panels, which are not formed as a continuous monolithic construction. Vertical joints are used to divide the wall into panels, and horizontal reinforcement is not continuous from one panel to the next. Recently, a diaphragm wall, believed to be one of the largest ever built, was successfully constructed in Egypt with a continuous horizontal reinforcement. This paper describes in detail a new construction method for a diaphragm wall system. In addition, the difficulties encountered during construction are highlighted. Movements of the wall during excavation are reported. A comparison between the new and traditional construction methods is carried out in terms of cost and schedule. Applying the method presented in this paper offers substantial opportunity for reducing the steel reinforcement requirement and eliminating the use of shoring systems or ground anchors. 相似文献
169.
Norhan Elassy Shady ElDafrawy Amira O. Abd ElAzim Om Ali Y. ElKhawaga Amr Negm 《IET nanobiotechnology / IET》2020,14(8):680
This study evaluated the biochemical, molecular, and histopathological mechanisms involved in the hypoglycaemic effect of zinc oxide nanoparticles (ZnONPs) in experimental diabetic rats. ZnONPs were prepared by the sol–gel method and characterised by scanning and transmission electron microscopy (SEM and TEM). To explore the possible hypoglycaemic and antioxidant effect of ZnONPs, rats were grouped as follows: control group, ZnONPs treated group, diabetic group, and diabetic + ZnONPs group. Upon treatment with ZnONPs, a significant alteration in the activities of superoxide dismutase, glutathione peroxidase, and the levels of insulin, haemoglobin A1c, and the expression of cluster of differentiation 4+ (CD4+), CD8+ T cells, glucose transporter type‐4 (GLUT‐4), tumour necrosis factor, and interleukin‐6 when compared to diabetic and their control rats. ZnONPs administration to the diabetic group showed eminent blood glucose control and restoration of the biochemical profile. This raises their active role in controlling pancreas functions to improve glycaemic status as well as the inflammatory responses. Histopathological investigations showed the non‐toxic and therapeutic effect of ZnONPs on the pancreas. TEM of pancreatic tissues displayed restoration of islets of Langerhans and increased insulin‐secreting granules. This shows the therapeutic application of ZnONPs as a safe anti‐diabetic agent and to have a potential for the control of diabetes.Inspec keywords: nanoparticles, transmission electron microscopy, cellular biophysics, sugar, nanomedicine, nanofabrication, zinc compounds, molecular biophysics, biochemistry, tumours, enzymes, biomedical materials, biological organs, blood, diseases, patient treatment, II‐VI semiconductors, wide band gap semiconductors, scanning electron microscopy, sol‐gel processing, semiconductor growthOther keywords: molecular mechanisms, histopathological mechanisms, zinc oxide nanoparticles, experimental diabetic rats, hypoglycaemic effect, antioxidant effect, control group, diabetic group, CD4+, CD8+ T cells, glucose transporter type‐4, control rats, GLUT‐4 expression, streptozotocin‐induced diabetic rats, biochemical mechanisms, safe antidiabetic agent, inflammation response, sol‐gel method, transmission electron microscopy, scanning electron microscopy, SEM, TEM, superoxide dismutase, glutathione peroxidase, insulin levels, haemoglobin A1c, differentiation 4+ T cells, tumour necrosis factor, interleukin‐6, blood glucose control, pancreas functions, glycaemic status, therapeutic effect, pancreatic tissues, Langerhans islets, insulin‐secreting granules, ZnO 相似文献
170.
Mourad Hebatallah M. Al-Bassiouni Abd El-Aziz M. Emam Sherief S. Al-Hussaini Emad K. 《Wireless Personal Communications》2003,25(4):263-275
The effect of block, convolutional and Turbo coding on the probability of error and the capacity are investigated for CDMA Low Earth Orbit (LEO) Satellite systems. The model employed assumes a contaminated Gaussian traffic model to be more compatible with different population areas. The conventional Gaussian distribution can be considered as a special case. 相似文献