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71.
    
Introducing sulfur functionalities is reported as an efficacious route to regulate the electron distribution of single-atomic Fe sites for improving the oxygen reduction reaction (ORR) activity, however, it remains controversial about the role of type of sulfur functionalities in enhancing the ORR activity. Herein, this study revisits the role of sulfur functionalities in regulating the electron distribution of single-atomic Fe sites by the construction of single-atomic Fe-N4 sites with sulfur functionalities (FeSNC) using sulfur-containing molecules with different molecular structures. X-ray absorption spectroscopy and theoretical calculations confirm that thiophene S and oxidized S both possess the electron-donating properties for regulating the electronic distribution of Fe-N4 sites, which is beneficial to weaken the adsorption of the ORR intermediates. As expected, the optimal FeSNC has attractive ORR activity with half-potential of 0.76 V in 0.5 m H2SO4 and 0.91 V in 0.1 m KOH along with remarkable Zn-air battery performance. Moreover, the developed synthetic method has also been extended to construct B and P regulated FeNC catalysts.  相似文献   
72.
    
To achieve a more realistic understanding of how the supply chain's components interact, it is helpful to consider the operational limitations of the underlying supply chain while analyzing cooperative advertising. This paper studies cooperative advertising in a manufacturer–retailer supply chain under the practical operational assumption that the manufacturer's production capacity is limited. The retailer advertises locally, and the manufacturer advertises in national media and supports part of the retailer's promotional costs. Equilibria are determined under two different scenarios. In the first scenario, both retailer and manufacturer move simultaneously, while in the second scenario, they move sequentially, with the manufacturer being the leader. The sales function is a bivariate version of the diminishing returns response function. When the production capacity is unlimited, several important properties can be proven, which cannot be shown analytically for the existing sales functions. Considering the production‐capacity constraint leads to new managerial insights into cooperative advertising. For example, only if the production capacity is large enough, both manufacturer and retailer are better off under the second scenario than the first scenario. In other words, the sequential move is not necessarily Pareto‐improving when the production capacity is limited. It is also observed that, under the first scenario, there are multiple equilibria whenever the production capacity is not too high. Under the second scenario, the manufacturer supports the retailer only when the retailer's margin is relatively small compared to the manufacturer's margin and production capacity.  相似文献   
73.
The aim of this research is inspecting the efficiency of physical-chemical and biological processes with the active sludge method in the wastewater of the Pars Oil Refinery Company. This research was done from 26th, January 2007 and continued up to 27th, May 2007. The main operation in Pars oil refinery is to produce lubricants. This research tries to examine and evaluate the performance of treatment system at the refinery to decrease microorganism in the industrial wastewater in a laboratory scale pilot. The pilot has two sections; physical-chemical section, including Dissolved Air Flotation system, and biological section, including active sludge reactor and clarifier. This investigation carried on a 10 liter Dissolved Air Flotation reactor and an active sludge reactor in a laboratory scale. The volume of the aerireactor (aeration reactor) was 10 liters, and the volume of the secondary sediment was 3.5 liters. The waste water of the refinery was used as inlet flow of the pilot and necessary sludge was obtained at first from the Shahrak Ekbatan waste water treatment system. After analyzing the test results, it was concluded that the average percentage of excluding oil, Chemical Oxygen Demand and Biological Oxygen Demand was 29.7, 49 and 27.8 respectively. This indicates the effective role of physical treatment in decreasing oily emulsion material that would result in decreasing organic density in untreated wastewater. In biological system, the efficiency of excluding Chemical Oxygen Demand and Biological Oxygen Demand is 73.4 and 84.7, respectively. This confirms high efficiency of this unit. The samples taken from entering (influent) and exiting (effluent) wastewater of both units were tested. Standard Methods were applied to determine the considered physical and chemical parameters.  相似文献   
74.
In this research, we aimed at improving the setting properties and biocompatibility of the mineral trioxide aggregate‐like cements while maintaining the main chemical formula. Consequently, chitosan and zirconium oxide were added to the cement instead of bismuth oxide to improve the mechanical behavior, limit the possible toxicity, and enhance the bioactivity of the cements. Adding zirconia resulted in a shorter setting time and adding chitosan contributed to the setting time, mechanical strength, and biocompatibility at the same time. Thus, cements containing both chitosan and zirconia had the shortest setting time, highest compressive strength, and apatite‐forming ability.  相似文献   
75.
Journal of Materials Science: Materials in Electronics - In this paper, (Co–TeO2) nanostructures were synthesized using the microwave-assisted method for the fabrication of...  相似文献   
76.
Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomerat...  相似文献   
77.
78.
    
In this study, microwave hybrid sintering and conventional sintering of Al2O3- and Al2O3/ZrO2-laminated structures fabricated via aqueous tape casting were investigated. A combination of process temperature control rings and thermocouples was used to measure the sample surface temperatures more accurately. Microwave hybrid sintering caused higher densification and resulted in higher hardness in Al2O3 and Al2O3/ZrO2 than in their conventionally sintered counterparts. The flexural strength of microwave-hybrid-sintered Al2O3/ZrO2 was 70.9% higher than that of the conventionally sintered composite, despite a lower sintering temperature. The fracture toughness of the microwave-hybrid-sintered Al2O3 increased remarkably by 107.8% despite a decrease in the relative density when only 3 wt.% t-ZrO2 was added. The fracture toughness of the microwave-hybrid-sintered Al2O3/ZrO2 was significantly higher (247.7%) than that of the conventionally sintered composite. A higher particle coordination and voids elimination due to the tape casting and the lamination processes, the microwave effect, the stress-induced martensitic phase transformation, and the grain refinement phenomenon are regarded as the main reasons for the mentioned outcomes.  相似文献   
79.
80.
Multimedia Tools and Applications - The segmentation of moving objects become challenging when the object motion is small, the shape of object changes, and there is global background motion in...  相似文献   
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