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1.
Alcoholic patients commonly experience cognitive decline. It is postulated that cognitive dysfunction is caused by an alcohol-induced region-selective brain damage, particularly to the prefrontal region, and grey and white matter may be affected differently. We used a proteomics-based approach to compare protein expression profiles of the dorsolateral prefrontal cortex (Brodmann area 9 (BA9)) from human alcoholic and healthy control brains. Changes in the relative expression of 110 protein 'spots' were identified in the BA9 grey matter, of which 54 were identified as 44 different proteins. In our recent article, 60 protein spots were differentially expressed in the BA9 white matter and 18 of these were identified (Alexander-Kaufman, K., James, G., Sheedy, D., Harper, C., Matsumoto, I., Mol. Psychiatry 2006, 11, 56-65). Additional BA9 white matter proteins are identified here and discussed in conjunction to our grey matter results. Thiamine-dependent enzymes transketolase and pyruvate dehydrogenase (E1β ubunit) were among the proteins identified. To our knowledge, this is the first time a disruption in thiamine-dependent enzymes has been demonstrated in the brains of 'neurologically uncomplicated' alcoholics. By identifying protein expression changes in prefrontal grey and white matter separately, hypotheses may draw upon more mechanistic explanations as to how alcoholism causes the structural alterations associated with alcohol-related brain damage and cognitive dysfunction.  相似文献   
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A more reliable and stable method, compared to the previous one developed by the present writers, of stiffness-damping simultaneous identification of shear-type building structures is proposed using stationary random records under limited observation. It is shown that when stationary random horizontal accelerations are recorded at the floors just above and below a specific story in a shear building model, the story stiffness and the damping ratio can be identified uniquely. The viscous damping coefficient and the material damping ratio can also be identified simultaneously in a numerical model structure. It is also shown that unfavorable effects by extraneous noises, including measurement noises, due to wind excitation, building facilities, and the motion of the occupants can be eliminated partially by using the present method. The accuracy of the present identification method is investigated through the actual records under limited observation in a base-isolated building.  相似文献   
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For a simplified model of a structure-pile-soil system, semiexplicit forms of the responses to random earthquake inputs are derived together with sensitivity expressions of the random responses with respect to a certain model parameter. Originally this model has a non-tridiagonal stiffness and damping matrices with single earthquake input. It is shown for the first time that independent treatment of the free-field ground and multiple imposition of the free-field ground response into the structure-pile system allow for a transformation of the governing equations so that the final form has tridiagonal stiffness and damping matrices. Closed-form expressions of the inverse of the tridiagonal matrix lead to semiexplicit expressions of the random responses and their sensitivities with respect to a certain model parameter.  相似文献   
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Metal–organic frameworks (MOFs)/coordination polymers are promising materials for gas separation, fuel storage, catalysis, and biopharmaceuticals. However, most applied research on MOFs is limited to these functional materials thus far. This study focuses on the potential of MOFs as structural adhesives. A sintering technique is applied to a zeolitic imidazolate framework-67 (ZIF-67) gel that enables the joining of Cu substrates, resulting in a shear strength of over 30 MPa, which is comparable to that of conventional structural adhesives. Additionally, systematic experiments are performed to evaluate the effects of temperature and pressure on adhesion, indicating that the removal of excess 2-methylimidazole and the by-product (acetic acid) from the sintered material by vaporization results in a microstructure composed of large spherical ZIF-67 crystals that are densely aggregated, which is essential for achieving a high shear strength.  相似文献   
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Developments in asymmetric hydrogenation from an industrial perspective   总被引:1,自引:0,他引:1  
Examples of developments in asymmetric hydrogenation from various perspectives, in an effort to improve efficiency, are reported. Discussed in this Account are (1) the improved synthesis of BINAP ligands, (2) the design of SEGPHOS ligands for higher enantioselectivity, (3) a new protocol with fewer reaction steps to synthesize beta-aminoesters, and (4) a novel asymmetric hydrogenation mediated by a copper catalyst.  相似文献   
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An efficient and systematic procedure is proposed for finding the optimal damper positioning to minimize the dynamic compliance of a planar building frame. The dynamic compliance is expressed in terms of the transfer function amplitudes of the interstory drifts evaluated at the undamped fundamental natural frequency. The dynamic compliance is minimized subject to a constraint on the sum of the damping coefficients of added dampers. Optimality criteria are derived and the optimal damper positioning is determined via an original steepest direction search algorithm. This algorithm enables one to find an optimal damper positioning sequentially for gradually increasing damper levels. The influences of support-member stiffnesses on the response suppression level and on the optimal damper positioning are also disclosed numerically. Copyright © 1998 John Wiley & Sons, Ltd.  相似文献   
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Heat transfer characteristics and flow patterns were measured over a plate for various separation distances between the nozzle exit and target plate when air issues from a sharp-edged cross-shaped nozzle and impinges on a plate. The local heat transfer coefficients in the radial direction for different circumferential positions were calculated using the wall temperatures measured by means of thermocouples, and flow patterns were observed using an oil-titanium IV oxide method. The isotherms of the infrared images were also measured using an infrared radiometer with a two-dimensional array of indium-antimony (InSb) sensors. The geometric axes were switched as a result of the self-induced velocity of a vortex filament; the convex corners became flat and the concave corners generated outward ejection. The distributions of the iso-heat transfer coefficient contours correspond well to the flow pattern and the isotherm contours. These contours extended diagonally and demonstrated the St. Andrew's cross pattern for short separations, subsequently changing to an octagonal pattern, and then becoming circular at large separations. The correspondence of the heat transfer characteristics to the flow behavior, as well as the heat transfer mechanism are also described. © 1998 Scripta Technica, Heat Trans Jpn Res, 27(3): 192–204, 1998  相似文献   
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