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81.
Diagnosis of small B-cell lymphomas is sometimes difficult without fresh tissue for flow cytometry (FC) or immunohistochemistry (IHC). Therefore, we examined the usefulness of a paraffin section IHC panel consisting of antibodies to CD5, CD10, CD20, CD23, CD43, and cyclin D1. We tested 55 formalin-fixed small B-cell lymphomas, including 16 small lymphocytic lymphomas (SLLs), 10 mantle cell lymphomas (MCLs), 25 follicle center lymphomas (FCLs), and 4 mantle zone lymphomas (MZLs). Seventeen cases had B5-fixed sections that were stained in the same manner. The findings were correlated with FC immunophenotyping when available. All of the SLLs and 90% of the MCLs expressed CD5 by IHC, with occasional weak expression in some MCLs. All of the FCLs and MZLs lacked CD5 expression. These results were comparable to those obtained by FC. CD43 expression was seen in 100% of the SLLs, 90% of the MCLs, and 75% of the MZLs. CD23 expression was seen in 94% of the SLL; of these, 100% also showed expression of CD23 by FC. Cyclin D1 was detected in all of the MCLs by IHC but also in 3 of the 16 SLLs. CD23 was absent in all of the MCLs. CD10 expression was present in 21 (95%) of 22 FCLs. All of the 17 cases fixed in B5 showed a decreased immunoreactivity for CD5 in the neoplastic cells. In contrast, CD10 immunoreactivity was judged better in B5-fixed sections. We concluded, therefore, that anti-CD5 and -CD10 were useful tools in the differential diagnosis of B-cell lymphomas of small lymphocytes and that a paraffin-section IHC panel consisting of antibodies to CD5, CD10, CD20, CD23, CD43, and cyclin D1 was a useful ancillary technique that compared favorably with FC.  相似文献   
82.
In this study, the economic and technological benefits of the usage of alder wood instead of beech wood as a raw material in plywood and laminated veneer lumber (LVL) manufacturing were compared, besides the conservation of national forest resources. For this aim, some technological properties of plywood and LVL panels manufactured from beech and alder logs were determined, and then compared with the values indicated in related standards. According to the results of this study, mechanical strength values of beech plywood and LVL panels were higher than those of alder panels. Bending strength mean values of plywood panels were higher than the limit values indicated in DIN 68705-3 and DIN 68792. Shear strength mean values obtained for the plywood panels manufactured from alder logs were above the limit value (1.0 N/mm2) indicated in EN 314-2 standard. Mechanical strength values of beech LVL panels were also higher than those of alder LVL panels. When the annual increments of beech and alder trees in 1 ha and the time they need to reach suitable diameters for the manufacturing rotary cut veneers were taken into consideration, it was calculated that alder trees allow 3.82 times additional physical harvesting than beech trees.  相似文献   
83.
By composing (Eudragit S) with fatty acids (stearic acid (SA), palmitic acid (PA), and myristic acid (MA)), form‐stable phase change materials (PCMs), which can retain the same shape in a solid state even when the temperature of the PCMs is over the melting points of the fatty acids, are prepared. The compatibility of fatty acids with the Eudragit S is proved by microscopic investigation and infrared (FTIR) spectroscopy. The melting and crystallization temperatures and the latent heats of melting and crystallization of the form‐stable PCMs are measured by Differential Scanning Calorimetry (DSC) method. The maximum mass percentage of all fatty acids in the form‐stable PCMs is found as 70%, and no leakage of fatty acid is observed at the temperature range of 50–70°C for several heating cycles. Thermal properties obtained from the DSC analysis indicate that the Eudragit S/fatty acid blends as form‐stable PCM have great potential for passive solar latent heat thermal energy storage (LHTES) applications in terms of their satisfactory thermal properties and utility advantage. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1402–1406, 2006  相似文献   
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In this study, we present the results and implications of an experimental study into the effect of gold-ion implantation on the actuation performance of ionic-type conducting polymer actuators, represented here by cantilevered tri-layer polypyrrole (PPy) actuators. We implant gold ions beneath the outer surfaces of PPy-based conducting polymer layers of the actuators in order to increase the conductivity of these layers, and therefore improve the overall conductivity of the actuators. A Filtered Vacuum Cathode Arc (FVCA) ion source was used to implant gold particles into the conducting polymer layers. Electrode resistance and capacitance, surface resistance, current response, mechanical work output of the actuator samples were measured and/or calculated for the actuator samples with and without gold implantation in order to demonstrate the effect of the gold-implantation. The current passing through the conducting polymer electrodes during their ‘electrochemomechanical’ actuation was measured to determine the charging time constant of the actuators. The mechanical displacement output of the actuators was recorded. The results demonstrate that the conductivity of the actuators increases noticeably, which has a flow on effect on the current response (i.e., charge injected into the polymer layers) and the mechanical work output. While the gold implanted actuators had a higher mechanical stiffness therefore a smaller displacement output, their time constant is smaller, indicating a higher response speed. The gold-implanted actuators generated a 15% higher mechanical work output despite the adverse effects on the polymer of the vacuum processing needed for the ion implantation.  相似文献   
87.
Conjugated polymers are promising actuation materials for bio/micromanipulation systems, biomimetic robots, and biomedical devices. For these applications, it is highly desirable to have predictive models available for feasibility study and design optimization. In this paper a scalable model is presented for trilayer conjugated polymer actuators based on J. Madden's diffusive-elastic-metal model. The proposed model characterizes actuation behaviors in terms of intrinsic material parameters and actuator dimensions. Experiments are conducted on polypyrrole actuators of different dimensions to validate the developed scaling laws for quasi-static force and displacement output, electrical admittance, and dynamic displacement response.  相似文献   
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In this study, we used depth-sensing indentation (DSI) technique to investigate some mechanical properties (reduced elastic modulus, indentation hardness, and creep) of polypyrrole (PPy) conducting polymer obtained with different support electrolyte concentration. The influence of support electrolyte concentration on these parameters was also determined. The order of doping degree of the samples was determined by cyclic voltammetry. The indentation load–displacement curves of the samples were obtained under different peak load levels with a 70 s holding time at maximum load. Reduced elastic modulus and hardness values were determined by analysis of these curves using the Feng–Ngan (F–N) and Tang–Ngan (T–N) methods, respectively. Both reduced elastic modulus (E r) and indentation hardness (H) exhibited significant peak load dependence, i.e., indentation size effect (ISE). It was found that both E r and H values decreased as the support electrolyte concentration was increased. This was explained by an increase in the free volume as the doping degree was raised. The creep behavior of the samples was monitored from the load holding segment of the load–unload curves. It was found that creep increases with the increasing support electrolyte concentration.  相似文献   
90.
A hybrid nanostructure with partially reduced graphene oxide (rGO) and carbon nanofibers (CNFs) was fabricated and used as supercapacitor electrodes. A straightforward, environmentally friendly, and low‐cost microwave‐assisted reduction process was developed for the synthesis of rGO/CNF hybrid structures. The fabricated supercapacitor devices showed a specific capacitance of 95.3 F g?1 and a superior long‐term cycling stability. A capacitance retention of more than 97% after 11 000 galvanostatic charge discharge cycles was obtained. These and other results reported in this paper indicate that high‐rate, all‐carbon, rGO/CNF hybrid nanostructures are highly promising supercapacitor electrode materials.  相似文献   
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