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Food Science and Biotechnology - During tempeh production, boiling was considered as heat treatment that could significantly reduce or eliminate bacterial population in soybean before fungal...  相似文献   
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This paper studies the applicability of extrusion-based 3D printing for constructing novel shapes from potato puree and the effects of four additives (agar, alginate, lecithin, and glycerol) added separately at three concentrations (0.5, 1, 1.5%) on the internal strength, mechanical properties, microstructure, and color of potato puree. The printability of the potato puree and the mixtures was assayed by examining the consistency of the extrusions and the stability and accuracy of the printed patterns. The results indicate that better printing was achieved at a nozzle height of 0.5 cm and a nozzle diameter of 4 mm, with concentrations of alginate and agar between 0.5–1.5% and 0.5–1%, respectively, providing the best printability and end product stability, which was attributed to their respective high mechanical characteristics and specific mechanical energy (SME) values. Scanning electron microscopy (SEM) revealed that more convolutions were induced in the potato puree upon the addition of agar or alginate, which increased the puree stability. 3D printing did not significantly affect the surface color parameters of the final product. This study showed that the 3D printing process is a critical factor for initializing the production of customized healthy products.  相似文献   
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Electrical generators of renewable electricity resources are quiet, clean and reliable. Optimal placement of renewable electricity generators (REGs) results in reduction of objective functions like losses, costs of electrical generation and voltage deviation. Because of recent technology developments of photovoltaic units, wind turbine and fuel cell units, only these generators are considered in this paper. This work presents a multiobjective optimization algorithm for the siting and sizing of renewable electricity generators. The objectives consist of minimization of costs, emission and losses of distributed system and optimization of voltage profile. This multiobjective optimization is solved by the Improved honey bee mating optimization (HBMO) algorithm. In the proposed algorithm, an external repository is considered to save non-dominated (Pareto) solutions found during the search process. Since the objective functions are not the same, a fuzzy clustering technique is used to control the size of the repository within the limits. This algorithm is executed on a typical 70-bus test system. Results of the case study show the proper siting and sizing of REGs are important to improve the voltage profile, reduce costs, emission and losses of distribution system. The main feature of the algorithm refers to its accuracy and calculation speed.  相似文献   
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A new technique for optimal planning of MV and LV segments of a distribution system is presented in this paper. The main goal is to find optimally distribution transformer and substation locations and ratings, as well as, the route and type of Medium Voltage (MV) and Low Voltage (LV) feeders. The proposed technique is applicable to both uniform and non-uniform load densities areas. In this method, the planning area is divided into regions with relatively uniform load density such as urban, semi-urban, sub-urban. Each of regions is divided into zones, called LV zone. Each LV zone is supplied by an MV/LV transformer. The dimensions of LV zones are found based on the average load of each region. The placement and rating of MV/LV transformers, the type and route of LV conductors in an LV zone all depend on its loads’ location and power. Regarding the placement and rating of MV/LV transformers in planning area and the space of regions, the dimensions of a zone which is supplied by a HV/MV transformer, called MV zone, is determined. Additionally, the location and rating of HV/MV transformers as well as the feeder's routes and types are calculated. Since the dimensions of an LV zone influence the associated length of MV feeder, the MV feeder cost needs to be included in the total cost associated with the LV zone. This requires the MV feeder type to be known to calculate the corresponding cost. However, the MV feeder type is determined as an output from MV zone planning. As a result, an iterative based method is proposed to consider this common element in computations to develop integrated planning of both LV and MV zones. It is observed that the iterative technique quickly converges to the same results as the exhaustive search method.Discrete particle swarm optimization (DPSO) method is employed for solving the planning problem. The results are compared with nonlinear programming, genetic algorithm and exhaustive search methods. It is observed that DPSO is as accurate as the exhaustive search method for integrated planning of MV-LV distribution systems while its computation time is significantly lower.  相似文献   
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In this research, the corrosion resistance and adhesion property of a synthetic rubber-based primer reinforced with different ratios of micaceous iron oxide (MIO) pigments were studied. Coatings were applied on carbon steel panels and also on steel pipes of 219.1 mm outer diameter. Scanning electron microscopy (SEM) was used to investigate the dispersion of MIO particles in the rubbery matrix. The anticorrosion performance of the coatings was studied, using electrochemical impedance spectroscopy (EIS) and salt spray tests. In addition, the adhesion of primers to carbon steel substrates was evaluated by pull-off test. In order to investigate the effect of MIO particles on the flexibility of the pigmented primers, a cupping test was conducted. The adhesion of cold-applied tape to the formulated primers was assessed by peel adhesion test using hanging mass method. The results indicated that adding 5, 10, and 15 wt% of MIO pigments into the primer improved corrosion resistance of the coatings. An increase in the MIO loading up to 10 wt%, improved the adhesion of the primer to both steel substrate and cold-applied tape.  相似文献   
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In the present study, a magnetic niosomal nanocarrier for co-delivery of curcumin and letrozole into breast cancer cells has been designed. The magnetic NiCoFe2O4 core was coated by a thin layer of silica, followed by a niosomal structure, allowing us to load letrozole and curcumin into the silica layer and niosomal layer, respectively, and investigate their synergic effects on breast cancer cells. Furthermore, the nanocarriers demonstrated a pH-dependent release due to the niosomal structure at their outer layer, which is a promising behavior for cancer treatment. Additionally, cellular assays revealed that the nanocarriers had low cellular uptake in the case of non-tumorigenic cells (i.e., MCF-10A) and related high viability but high cellular uptake in cancer cell lines (i.e., MDA-MB-231 and SK-BR-3) and related low viability, which is evidenced in their high cytotoxicity against different breast cancer cell lines. The cytotoxicity of the letrozole/curcumin co-loaded nanocarrier is higher than that of the aqueous solutions of both drugs, indicating their enhanced cellular uptake in their encapsulated states. In particular, NiCoFe2O4@L-Silica-L@C-Niosome showed the highest cytotoxicity effects on MDA-MB-231 and SK-BR-3 breast cancer cells. The observed cytotoxicity was due to regulation of the expression levels of the studied genes in breast cancer cells, where downregulation was observed for the Bcl-2, MMP 2, MMP 9, cyclin D, and cyclin E genes while upregulation of the expression of the Bax, caspase-3, and caspase-9 genes was observed. The flow cytometry results also revealed that NiCoFe2O4@L-Silica-L@C-Niosome enhanced the apoptosis rate in both MDA-MB-231 and SK-BR-3 cells compared to the control samples. The findings of our research show the potential of designing magnetic niosomal formulations for simultaneous targeted delivery of both hydrophobic and hydrophilic drugs into cancer cells in order to enhance their synergic chemotherapeutic effects. These results could open new avenues into the future of nanomedicine and the development of theranostic agents.  相似文献   
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The simultaneous effect of particle size and concentration on the total gas holdup of slurry bubble column reactors was investigated in this work. The total gas holdup was measured for air–water–glass beads systems. Three solid concentrations and three particle diameters were used. It was found that increasing particle size at high constant concentration decreases gas holdup. Moreover, increasing solid concentration decreases gas holdup and this decreasing effect is higher for larger particles. Also, solid particles have two effects on hydrodynamics, namely, changing the viscosity and density of the liquid phase as well as hindering the bubbles from rising within the column by the collision phenomenon. Therefore, a novel correcting factor was introduced to correct the gas holdup. The hindering factor considers both the collision efficiency affected by the particle size as well as the solid concentration. A novel correlation was developed to predict the experimental data of the three-phase gas holdup.  相似文献   
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