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排序方式: 共有381条查询结果,搜索用时 15 毫秒
31.
Acid Mine Drainage (AMD) originates from the oxidation and leaching of sulphide minerals present in coal and metalliferrous ore bodies and gives rise to several environmental degradation problems. An investigation has been carried out to combat the acidic water problems. Results of this investigation indicate that application of anionic surfactant (sodium lauryl sulphate) and food preservatives (sodium benzoate and potassium sorbate) effectively abate the acid formation at low concentration levels (15–40 ppm) as tested in laboratory as well as at pilot-scale levels. Acidity, sulphate and iron concentrations are found to reduce by over 70 percent and remained low for more than three months after treatment. Thus this investigation demonstrates the management of these problems in an environmentally safe manner by controlling acid formation at its source. 相似文献
32.
AI El-Sakka HM Hassoba RM Chui RS Bhatnagar R Dahiya TF Lue 《Canadian Metallurgical Quarterly》1997,158(6):2284-2290
PURPOSE: Transforming growth factor beta (TGF-beta) is involved in numerous vital processes including tissue fibrosis. Our objective was to study the role of TGF-beta in the induction of a Peyronie's-like condition and to produce an animal model for the further study of Peyronie's disease. MATERIALS AND METHODS: Twenty-four adult male Sprague-Dawley rats were divided into two groups. Different concentrations of cytomodulin, a synthetic heptopeptide with TGF-beta-like activity, were injected into the tunica of each rat from the first group (n = 18). Rats in the second group (n = 6) received saline injections as a control. The tunical tissues were taken after 3 days, 2 weeks, and 6 weeks and were examined using Hart and Trichrome stains. In the same tissue samples, TGF-beta mRNA and protein expression were studied. RESULTS: Histological alterations were observed in 15 out of 18 cytomodulin-injected rats, especially in tissue examined after 6 weeks. The most prominent changes were chronic cellular infiltration, focal and diffuse elastosis, thickening, disorganization and clumping of the collagen bundles. Results from immunoblot revealed remarkable TGF-beta1 protein expression in all the cytomodulin-injected rats only after 2 and 6 weeks. No remarkable TGF-beta2 or TGF-beta3 protein expression was observed. TGF-beta1 mRNA expression in the cytomodulin-injected rats was noticed in rats injected with higher concentrations after 3 days, while it was expressed in all rats after 2 weeks. There was no expression in the control group after either 3 days or 2 weeks. CONCLUSIONS: Cytomodulin can induce Peyronie's-like condition in the rat penis, which may explain the role of TGF-beta in the pathogenesis of Peyronie's disease. 相似文献
33.
T. Saud D.P. SinghT.K. Mandal Ranu GadiH. Pathak M. SaxenaS.K. Sharma R. GautamA. Mukherjee R.P. Bhatnagar 《Biomass & bioenergy》2011,35(2):932-941
Biomass is widely used as energy source in rural households in India. Biomass samples and socio-economic data have been collected at district level in the rural areas of Indo-Gangetic plain (IGP), India to determine the emissions of trace gases and aerosols from domestic fuels. Dung cake, fuelwood and crop residue are main sources of energy in rural areas of the IGP. Dung cake is the major domestic fuel (80-90%) in the rural areas of Delhi, Punjab, Haryana, Uttar Pradesh, Bihar and West Bengal, whereas, 99% of rural households in Uttarakhand use wood as the main energy source. Using crop production data and usage of crop residues as energy, new consumption values have been estimated (21.13 Mt). Present information on the domestic fuel usage would be helpful in determining budgets estimates of trace gases and aerosols for India. 相似文献
34.
Alkyl and aromatic mercaptans are among important organic sulfur compounds distributed in petroleum products. The mercaptans cause foul odor and are corrosive toward metals. In addition, mercaptans may cause oxidative deterioration as well as inhibit the performance of various additives (TEL, antioxidants) in finished products. Therefore, it is necessary to remove them, either by extractive processes or by converting them into innocuous disulfides. Such processes are usually referred to as “sweetening.” 相似文献
35.
An 8-day-old newborn presented with non-bilious vomiting, upper abdominal fullness, and failure to pass meconium. Plain radiographs revealed gastric pneumatosis (GP). At operation, he was found to have a non-obstructive preduodenal portal vein, preampullary duodenal atresia, asplenia, and malrotation. The baby was treated by duodeno-duodenostomy without mobilizing the portal vein and correction of the malrotation according to Ladd's procedure. He made an uneventful recovery and the GP resolved spontaneously. The malformative process was believed to have occurred at or soon after the 5th week of gestation, and the GP probably resulted from intramural air tracking through mucosal tears caused by high intragastric pressure. 相似文献
36.
37.
Ceramic bushings of different geometries and sizes have been developed for drawing continuous glass fibres as reinforcements. Both pure alumina and stabilised zirconia have been used in fabricating such bushings. The characteristics of fibres drawn through these bushings are shown to be similar to those drawn through conventional platinum-rhodium ones. Alumina bushings have poor corrosion resistance properties with respect to E-glass but are satisfactory for A- and C- glass compositions. Stabilised zirconia bushings give superior performance with regard to E-glass. 相似文献
38.
The Thermoelectric emfs of thermocouples formed by amorphous METGLAS 2826 (Fe40Ni40P14B6) and METGLAS 2826B (Fe29Ni49P14B6Si2) with standard thermocouple wires like copper, chromel, alumel, etc., were measured as a function of temperature between
−196° C and 30° C to assess their suitability as thermoelectric temperature sensors. Thermoelectric emfs generated by METGLAS
2826/Cu and METGLAS 2826B/Cu thermocouples at −196° C are about an order of magnitude smaller when compared to thermal emfs
of a standard copper/constantan thermocouple at the same temperature. 相似文献
39.
Anil K Bhatnagar B Bhanu Prasad N Ravi R Jagannathan 《Bulletin of Materials Science》1984,6(6):1059-1062
Mössbauer measurements have been performed on a number of metallic glasses. The temperature dependence of average hyperfine or internal magnetic fieldH eff(T) arises from long wavelength spin wave excitations in these glasses. Values ofB 3/2 andC 5/2 are in general much higher than those observed for crystalline ferromagnets indicating higher density of states for spin waves in amorphous ferromagnets. 相似文献
40.
Arushi Jain Vishal Bhatnagar Annavarapu Chandra Sekhara Rao Manju Khari 《Computational Intelligence》2023,39(6):1088-1111
Artificial intelligence and deep learning have aided ocular disease through experiments including automatic illness recognition from images of the iris, fundus, or retina. Automated diagnosis systems (ADSs) provide services for the benefit of humanity and are essential in the early detection of harmful diseases. In fact, early detection is essential to avoid total blindness. In real life, several diagnostic tests such as visual ocular tonometry, retinal exam, and acuity test are performed, but they are conclusively time demanding and stressful for the patient. To consume time and detect the retinal disease earlier, an efficient prediction method is designed. In this proposed model, the first process is data collection that consists of a retinal disease dataset for testing and training. The second process is pre-processing, which executes image resizing and noise filter for feature extraction. The third step is feature extraction, which extracts the image's form, size, color, and texture for classification with CNN based on Inception-ResNet V2. The classification process is done by using the SVM with the extracted features. The prediction of diseases is classified such as normal, cataract, glaucoma, and retinal disease. The suggested model's performance is assessed using performance indicators such as accuracy, error, sensitivity, precision, and so forth. The suggested model's accuracy, error, sensitivity, and precision are 0.96, 0.962, 0.964, and 0.04, respectively, higher than existing techniques such as VGG16, Mobilenet V1, ResNet, and AlexNet. Thus, the proposed model instantly predicts retinal disease. 相似文献