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41.
A novel terpolymer acts as an effective chelating ion exchanger which was synthesized using 2-amino-6-nitro-benzothiazole and semicarbazide with formaldehyde (BSF) by solution condensation technique. Its ion exchange properties was determined against certain metal ions viz. Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Pb2+ using batch equilibrium technique with different electrolyte concentrations, pH ranges and time intervals. The results of batch studies revealed that the separation of the selected metal ions from the aqueous solution by the terpolymer is found to be excellent compared to the available commercial resins and earlier reported resins. The order of metal ion uptake at higher concentrations by the BSF terpolymer at lower pH is Cu2+ > Ni2+ > Fe3+ and at lower concentration at higher pH is Zn2+ > Co2+ > Pb2+. The reusability of the resin was also reported for its effective ion-exchange behaviour for several cycles. The adsorption isotherm model was evaluated and the results are in good agreement with each other. The order of kinetics was also determined and the resin follows pseudo-second-order kinetics. Moreover, the physico-chemical analysis gives strong evidence for the effective metal ion removal compared with the earlier reported and commercial resins. Earlier, the structure and the properties of the synthesized novel chelating resin were clearly elucidated by elemental, FTIR, UV–Vis, 1H & 13C NMR spectra, GPC, SEM and XRD.  相似文献   
42.
This study reports the conversion of Jatropha curcas oil to biodiesel catalyzed by sulphated zirconia loaded on an alumina catalyst using response surface methodology (RSM). Specifically, it studies the effect of interaction between process variables on the yield of biodiesel. Jatropha is found to be survived in different locations in South-East Asia. Jatropha oil is favoured to palm oil for its cold filter plugging the point (CFPP) values, making it a better option for use in cold climates. The increasing industrialization and modernization of the world have to a steep rise for the demand of petroleum products. Economic development in developing countries has led to huge increase in the energy demand. The crude oil demand of the country is met by imparting about 80%. Thus, the energy security has become a key issue for the nation as a whole. Petroleum-based fuels are limited. This article is an attempt to present the prevailing fossil-fuel scenario with respect to petroleum diesel, fuel properties of biodiesel of biodiesel resources for biodiesel production, processes for its production, purification, etc. At last, a discussion of stability of biodiesel is described here.  相似文献   
43.
Multimedia Tools and Applications - Maintaining the optimum growth rate and estimating the concentration of microalgae are critical in improving microalgae production. An efficient concentration...  相似文献   
44.
The Journal of Supercomputing - Rapid communication of viral sicknesses is an arising public medical issue across the globe. Out of these, COVID-19 is viewed as the most critical and novel...  相似文献   
45.
Fischer-Tropsch (FT) process has great potential to accomplish energy security but also for utilizing greenhouse gases to address the energy problem. Different kinds of feedstocks like coal, biomass (via gasification), CO2, methane (via reforming), and nonconventional energy sources are used to obtain the syn-gas (CO and H2). The formation of hydrocarbons in the FT process follows ASF distribution over the majority of the catalysts. It can be overcome by the application of a suitable catalyst, controlling the active metal interaction with the support and interaction of formed hydrocarbon with the support. The ratio of syn-gas is important to maintain the desired conversion and to have more selectivity towards C5+ products. Increase in the H2: CO ratios in the feed increases C5+ products and methane decreases. Whereas with the decrease in the ratios increases undesirable reactions and methane formation. In this article, we have discussed the recent literature from the viewpoint of increasing the C5+ selectivity. Support has a profound influence on product distribution. With the application of suitable support and controlling the interaction of the active sites yields the good CO conversion with fewer lighters and higher C5+ hydrocarbons.  相似文献   
46.
47.
The rapid growth of the Internet of Things (IoT) in the industrial sector has given rise to a new term: the Industrial Internet of Things (IIoT). The IIoT is a collection of devices, apps, and services that connect physical and virtual worlds to create smart, cost-effective, and scalable systems. Although the IIoT has been implemented and incorporated into a wide range of industrial control systems, maintaining its security and privacy remains a significant concern. In the IIoT contexts, an intrusion detection system (IDS) can be an effective security solution for ensuring data confidentiality, integrity, and availability. In this paper, we propose an intelligent intrusion detection technique that uses principal components analysis (PCA) as a feature engineering method to choose the most significant features, minimize data dimensionality, and enhance detection performance. In the classification phase, we use clustering algorithms such as K-medoids and K-means to determine whether a given flow of IIoT traffic is normal or attack for binary classification and identify the group of cyberattacks according to its specific type for multi-class classification. To validate the effectiveness and robustness of our proposed model, we validate the detection method on a new driven IIoT dataset called X-IIoTID. The performance results showed our proposed detection model obtained a higher accuracy rate of 99.79% and reduced error rate of 0.21% when compared to existing techniques.  相似文献   
48.
Quantum neural network filters for signal processing have received a lot of interest in the recent past. The implementations of these filters had a number of design parameters that led to numerical inefficiencies. At the same time the solution procedures employed were explicit in that the evolution of the time-varying functions had to be controlled. This often led to numerical instabilities. This paper outlines a procedure for improving the stability, numerical efficiency, and the accuracy of quantum neural network filters. Two examples are used to illustrate the principles employed.  相似文献   
49.
The design, fabrication, and experimental evaluation of an exploratory 8.2 W, microwave FM power amplifier for the 4-GHz band are presented. It operates on a frequency divide, amplify, and multiply scheme receiving about 2-4 dBm of FM signal in the 4-GHz band, divides the frequency coherently by two, amplifies the modulated signal to about 10.4 W, and doubles the frequency coherently, yielding about 8.2 W into standard 50-ω 4-GHz load, with an overall efficiency of about 30 percent. Frequency halving is accomplished by a wideband regenerative frequency divider yielding about 1-2 dBm of signal at 1995 MHz. The signal is amplified by commercial class C amplifiers and is restored to the 4-GHz band by a stacked varactor containing two 0.32 ω, 15-pF chips in a coaxial embodiment. This entire ensemble, with a total breakdown of 160 V, serves as a frequency doubler.  相似文献   
50.
The aim of this study was to evaluate the composition, nutritional and toxicology safety of GM potato Spunta lines compared to that of conventional potato Spunta. Compositional analyses were conducted to measure the proximate chemical composition with references to 14 components, total solid, protein, lipid, crude fibre, ash, carbohydrate, starch, reducing sugar, nonreducing sugar, sodium, calcium, potassium, phosphorus, and ascorbic acid. Some toxins and anti-nutrients compounds were determined. Feeding study of GM potatoes line (G2 and G3) in rats were done for 30 days. Four groups of albino rats were used for studying the effect and the safety assessment of GM potatoes Spunta G2 and G3. Group (I) was fed on control basal diet, group (II) was fed on control diet plus 30% freeze-dried nongenetically modified potato Spunta, group (III) was fed on control diet plus 30% freeze-dried genetically modified potato Spunta, and group (IV) was fed on control diet plus 30% freeze-dried genetically modified potato Spunta GMO G3. There were no significant differences between GM potatoes G2, G3, and Spunta control potato line in the proximate chemical composition. The levels of glycoalkaloids in transgenic potato tubers and nontransgenic were determined and there were also no significant differences between the GM potatoes and conventional potato line, the levels were in agreement with a safety level recommended by FAO/WHO (200 mg/ kg) for acute toxicity. Protease inhibitor activity and total phenol were estimated and no significant differences between the GM potatoes line and conventional potato Spunta line were found. During the period tested, rats in each group (I, II, III, IV) grew well without marked differences in appearance. No statistical difference were found in food intake, daily body weight gain and feed efficiency. But there is a slightly significant difference in finally body weight between the control group and experimental groups. No significant difference were found in serum biochemical value between each groups, and also between relative organs weight (liver, spleen, heart, kidney, testes). From these results, it can be concluded that the GM potatoes Spunta line (G2 and G3) with Cry V gene are confirmed to have nearly the composition and biochemical characteristics as non-GM potato Spunta.  相似文献   
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