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31.
Neural Computing and Applications - Inefficient scheduling of a pipeline system may lead to severe degradation and substantial economic losses. Earlier studies mostly focussed on corrosion and...  相似文献   
32.
New nanocomposite hybrid films of a well dispersed cerium disulphate Ce(SO4)2 nanoparticles into the polyvinylpyrrolidone (PVP) matrix were prepared by a casting technique. The nanostructural nature and complex formation were investigated using the transmission electron microscopy (TEM), the nuclear magnetic resonance (NMR), and the Infrared (IR) spectroscopy. The magnetic measurements at room temperature, using a vibrating sample magnetometer (VSM), and the obtained magnetic parameters revealed that the investigated nanocomposites belong to a category of magnetically soft materials that find widespread applications in contemporary fine technologies. Optical absorption spectra were measured in the ultraviolet (UV)–visible region and the fundamental absorption edge Ea, the energy gap Eg and width of the tail of localized states Ee were evaluated and discussed in terms of the solid band theory. The monotonic increase of these optical parameters with the dopant concentration may be attributed to probable segregation effects occurring in the amorphous host matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
33.
Solid particles were dried in the riser of circulating fluidized bed with internals to study the drying kinetics. Experiments were conducted in a circulating fluidized bed, having perforated plates as internals covering wide range in the operating parameters. The effects of various operating parameters, i.e., initial moisture content, temperature, and flow rate, of the heating medium and solid circulation rate on the rate of drying have been critically examined. It has been observed from the present investigation that the presence of internals enhances the solids holdup in the riser of circulating fluidized bed. The drying efficiency of a circulating fluidized bed with internals has been compared with the drying performance of a circulating fluidized bed without internals under the same operating conditions.  相似文献   
34.
The microwave-assisted styrene epoxidation reaction with molecular O2 as an oxidant was studied over a sulfated Co–Y-doped ZrO2 solid catalyst. The microwave irradiation (400 W) resulted in similar styrene conversion and styrene oxide selectivity, in reduced time, as compared to conventional thermal heating. Higher power (800 W) of microwave irradiation decreased the styrene oxide selectivity as well as leading to the formation of styrene glycol. DMF was found to be the most suitable solvent for epoxidation of styrene with molecular O2 under microwave irradiation and yielded maximum oxide selectivity (91%) at 120 °C. The microwave-assisted oxidation reaction resulted in time saving and is energy conserving method.  相似文献   
35.
Wireless Sensor Network (WSN) technology is the real-time application that is growing rapidly as the result of smart environments. Battery power is one of the most significant resources in WSN. For enhancing a power factor, the clustering techniques are used. During the forward of data in WSN, more power is consumed. In the existing system, it works with Load Balanced Clustering Method (LBCM) and provides the lifespan of the network with scalability and reliability. In the existing system, it does not deal with end-to-end delay and delivery of packets. For overcoming these issues in WSN, the proposed Genetic Algorithm based on Chicken Swarm Optimization (GA-CSO) with Load Balanced Clustering Method (LBCM) is used. Genetic Algorithm generates chromosomes in an arbitrary method then the chromosomes values are calculated using Fitness Function. Chicken Swarm Optimization (CSO) helps to solve the complex optimization problems. Also, it consists of chickens, hens, and rooster. It divides the chicken into clusters. Load Balanced Clustering Method (LBCM) maintains the energy during communication among the sensor nodes and also it balances the load in the gateways. The proposed GA-CSO with LBCM improves the lifespan of the network. Moreover, it minimizes the energy consumption and also balances the load over the network. The proposed method outperforms by using the following metrics such as energy efficiency, ratio of packet delivery, throughput of the network, lifetime of the sensor nodes. Therefore, the evaluation result shows the energy efficiency that has achieved 83.56% and the delivery ratio of the packet has reached 99.12%. Also, it has attained linear standard deviation and reduced the end-to-end delay as 97.32 ms.  相似文献   
36.
BACKGROUND: Conventional biological waste‐water treatment techniques are insufficient to degrade large quantities of dissolved lignin discharged by small‐scale paper mills. The current investigation is aimed at comparing the overall performance of basic electrochemical reactor configurations such as batch, batch recirculation, recycle and single pass systems, in removing the organic part of waste‐water from a small‐scale, agro‐based paper industry. The effect of current density, supporting electrolyte concentration, duration of electrolysis, specific electrode surface and fluid flow rate on the removal of pollutants and energy consumption are critically evaluated. The improvement in biodegradability of the effluent during treatment is also noticed. RESULTS: The batch recirculation mode of operation was found to be superior in comparison with a batch system using the same specific electrode surface for both COD removal (73.3 vs. 64%) and capacity utilization (rate constant 1.112 × 10?3 vs. 1.049 × 10?3 cm s?1). The pollutant removal performance of the batch recirculation system improved considerably with increase in the circulation flow rate. At the best operating point in the recycle system, 59% of COD was removed, corresponding to a current efficiency of 68.9% and specific energy consumption of 18.46 kWh kg?1. The biodegradability index of the waste‐water was improved from 0.18 ± 0.01 to 0.36 ± 0.01. CONCLUSION: A recycle reactor was the best configuration, because of its flexibility of operation. Circulation flow rate and withdrawal flow rate enable the control of transfer coefficients and treatment duration respectively. Electrochemical treatment not only removes the bulk of the organic matter, but also makes the remaining pollutants more easily biodegradable. Copyright © 2009 Society of Chemical Industry  相似文献   
37.
The transport and mixing of contaminants in conduits is governed by advection, dispersion, and decay. Several models are available to trace the transport of such constituents and most assume that the principal mechanisms for transport are advection and reaction only. However in pipes where low velocities prevail, longitudinal dispersion is significant and models that neglect the dispersion effects fail to properly simulate the observed concentrations in low velocity pipes. This work presents a method for simulating the advection-dispersion-reaction process of constituent transport in water networks. A Eulerian–Lagrangian method is employed whereby the dispersion term in the governing equation is approximated using finite differences and the resulting first-order partial differential equation is then integrated using the method of characteristics. Analytical solutions of the transport equation are also derived to quantify the effect of neglecting dispersion at pipe junctions and to assess the accuracy of the proposed method. The Eulerian-Lagrangian method is tested on benchmark networks and on the field study at the Cherry Hill/Brushy Plains network. Results show that the model developed is capable of simulating transport with equal accuracy for low and high velocity flows with and without significant dispersion effects. It also performs better than other models because of the nonuniform grid distribution and the interpolation schemes used.  相似文献   
38.
39.

Abstract  

A series of 3,4,5-trisubstituted 1,2,4-triazoles have been synthesized from N 3-substituted amidrazones and anhydrides using HClO4-SiO2 at 80 °C under solvent-free conditions. The products were obtained in excellent yields within 5–10 min. Therefore, the present method will be of wide application in organic chemistry and medicinal chemistry.  相似文献   
40.
Muscadine grapes (Vitis rotundifolia Michx) are considered as excellent genetic resources for grape breeding programs as they are known for their hardiness and resistance to pests and diseases. However, contrary to popular belief, our study indicated that not all muscadine cultivars are resistant to anthracnose disease. In order to identify a source of genetic tolerance towards anthracnose among muscadine cultivars, a series of in-situ and ex-situ experiments were conducted through strict and sensitive screening processes. Two consecutive years of field evaluation of 54 grape cultivars showed various levels of anthracnose incidence among the cultivars between a scale of 0 (tolerant) to 5 (highly-susceptible). Resistance bioassay by inoculation of different spore densities of Elsinoë ampelina on 40 cultivars presented similar results and was consistent with those obtained from the field test. A real-time PCR analysis was conducted to investigate differences of gene expression between susceptible and tolerant cultivars and to confirm results by phenotypic identification. Expression of genes encoding chalcone synthase, stilbene synthase, polygalacturonase-inhibiting protein, chitinase and lipid transfer-protein was only detected in tolerant cultivars. Resistant muscadine cultivars identified in this study could be excellent candidates for grape disease resistance breeding programs.  相似文献   
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