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1.
The entrenched position now taken by participatory planning in urban planning practice has made the call for community participation in the planning process now higher than ever. Community participation has been well-acknowledged to give local people a voice in planning decisions. This paper assessed the level of participation by local people in the management of urban green spaces. Using a case study research approach, Kumasi city, once the garden city of Africa was selected as the study area. The Kumasi city authorities, and residents including opinion leaders, and officials of allied bodies on green spaces constituted the study’s target population. A blend of qualitative research techniques such as in-depth interviews, focus group discussion, and personal observation was employed whilst theoretical sampling technique was adopted. It was found out that the participation of the local people in the management of green space was low. The local people were neither consulted nor informed on green space projects (parks and gardens) by the city authorities. They were also not empowered to self-facilitate initiatives on green spaces and passively involved in final decisions on green spaces. To correct the situation, it is recommended that features of the communicative planning theory such as dialogue, consensus building, and facilitative leadership should be given attention in the urban planning system of Kumasi especially on green space projects.  相似文献   
2.
The majority of active pharmaceutical ingredients (APIs) found in oral dosage forms have a bitter taste. Masking the unpleasant taste of bitter, APIs is a major challenge in the development of such oral dosage forms. Taste assessment is an important quality-control parameter for evaluating taste-masked formulations of any new molecular entity. Hot-melt extrusion (HME) techniques, have very recently, been accepted from an industrial compliance viewpoint in relation to both manufacturing operations and development of pharmaceuticals. HME achieves taste masking of bitter APIs via various mechanisms such as the formation of solid dispersions and inter-molecular interactions and this has led to its wide-spread use in pharmaceutical formulation research. In this article, the uses of various taste evaluation methods and HME as continuous processing techniques for taste masking of bitter APIs used for the oral delivery of drugs are reviewed.  相似文献   
3.
Results are reported for corrosion fatigue of Type 304 stainless steel in boiling (140 C) 17.5M NaOH (46 wt pct) solution. Specimens, of the smooth round bar type, were cycled sinusoidally at 1.0 Hz in tension-tension about mean stresses of 248 MPa (36 ksi) and 124 MPa (18 ksi). Both solution annealed and sensitized specimens cracked readily in a transgranular mode. Sensitization did not increase the environmental effect. The caustic solution drastically shortened cyclic life and eliminated the endurance limit observed in air. Cyclic stress was a more important variable than mean stress as the lower mean stress did not significantly improve life. Anodic passivation did not increase cyclic life as it did for constant load SCC. Comparison of the SCC tests results with those of corrosion fatigue indicates that cyclic stresses, even when confined to the elastic region, accelerate failure more than sustained loads in the plastic region; this accelerative effect was most intense under anodic passivation. R. W. STAEHLE, formerly Professor of Metallurgical Engineering, and Director of The Fontana Corrosion Center, Ohio State University  相似文献   
4.
A novel topology of the bidirectional energy storage photovoltaic grid-connected inverter was proposed to reduce the negative impact of the photovoltaic grid-connected system on the grid caused by environmental instability. Using the proposed Inverter as a UPS power supply in case of a grid failure, storage electrical energy and regulating the energy delivered to the grid for reducing the pressure on the grid. A new artificial fish-swarm algorithm and variable step voltage perturbation method were presented to track the maximum power point of the solar panels. Analysis was done to reduce the output ripple of the inverter and sinusoidal pulse width modulation (SPWM) was selected to control the inverter. Model simulation was performed using PSpice software to obtain the volt-ampere characteristic curve of the solar panel output. The solar array simulator was used to verify the effect of maximum power point tracking at different light intensities. The study concludes that the maximum power point tracking (MPPT) efficiency of the bidirectional energy storage photovoltaic grid-connected inverter designed was as high as 99.9%. The distortion rate of the grid-connected current waveform was within 2% and the DC current component was less than 0.5%. The output voltage and power were in full compliance with the grid connection standard.  相似文献   
5.
Brittle materials have been widely employed for industrial applications due to their excellent mechanical, optical, physical and chemical properties. But obtaining smooth and damage-free surface on brittle materials by traditional machining methods like grinding, lapping and polishing is very costly and extremely time consuming. Ductile mode cutting is a very promising way to achieve high quality and crack-free surfaces of brittle materials. Thus the study of ductile mode cutting of brittle materials has been attracting more and more efforts. This paper provides an overview of ductile mode cutting of brittle materials including ductile nature and plasticity of brittle materials, cutting mechanism, cutting characteristics, molecular dynamic simulation, critical undeformed chip thickness, brittle-ductile transition, subsurface damage, as well as a detailed discussion of ductile mode cutting enhancement. It is believed that ductile mode cutting of brittle materials could be achieved when both crack-free and no subsurface damage are obtained simultaneously.  相似文献   
6.
Scholarship on immigrant entrepreneurship tends to focus on those in the developed world. In this paper, I attempt to shift the balance by focusing on Nigerian immigrant entrepreneurs in contemporary Ghana, specifically their locational and sectoral niches as well as inter-generational continuities and discontinuities. I do these by examining the outcomes of broad-based field work employing in-depth interviews and observations of these immigrant entrepreneurs in Accra - the capital, Kumasi—the second largest city after Accra, and Ashaiman—a sprawling sub-urban settlement. What emerges from analysis and discussion of empirical data is that, among other things, the activities of Nigerian immigrant entrepreneurs in contemporary Ghana reveal both old and new strands of sectoral participations, and the dynamics of locational and sectoral participations also evincing elements of precinctization (albeit incipient in form) and specialisation. Further, the nature of sectoral participation appears to embody shapes of continuity and discontinuity with those of their earlier generations in Ghana. These findings provide introductory glimpse to the unexplored phenomenon of Nigerian immigrant entrepreneurship in contemporary Ghana and further chart a way to compare to their predecessors.  相似文献   
7.
A dye‐sensitized solar cell (DSC) made of nanoporous ZnO film on aluminum‐doped zinc oxide (ZnO/AZO) transparent substrate has higher solar‐to‐electric energy conversion efficiency than a DSC consisting of nanoporous ZnO film deposited on conventional fluorine‐doped tin oxide (ZnO/FTO) transparent substrate. The ZnO/AZO DSC gave an overall conversion efficiency of 7.2% whereas the ZnO/FTO yielded a conversion efficiency of 4.5%. The film‐substrate orientation and higher light harvesting of the nanoporous ZnO film on the AZO after heating in air are mainly attributed to the higher energy conversion efficiency of the ZnO/AZO DSC. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
8.
Atomic force microscopy and nanoindentation have been applied to the study of thin molecularly templated polymer films. The template was chosen to be the readily hydrogen‐bonded cotinine molecule and three different polymer hosts, Elvamide® nylon, Nylon‐6, and poly(4‐vinylphenol) were compared. The host polymer was shown to affect the nature of the template‐host interaction resulting in varying surface morphologies and differences in the nanohardness. These observations were shown to reflect differences in the underlying interaction chemistry, specifically, whether or not the polymer may be imprinted in the film production process. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 877‐883, 2013  相似文献   
9.
Investigations concerning the behaviour of Gmelina arborea wood growing in a plantation in Ghana by the Kraft delignification process were carried out in the St. Petersburg (formerly Leningrad) Academy of Forest Technology and Engineering in the Commonwealth of Independent States (Russia).

The basic kinetic data such as the rate constant, order of reaction, temperature dependence and the energy of activation were calculated. The kinetic data obtained indicate that the dielignification of G. arborea is by a process similar to that of diffusion as occurs during chemical reactions. Consequently, the delignification process at temperature which was carried out at selected cooking conditions is not solely controlled by kinetic processes.  相似文献   
10.
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