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排序方式: 共有200条查询结果,搜索用时 15 毫秒
1.
This study used different metals to modify Rh/Al2O3 catalysts for NO reduction in a simulated waste incineration flue gas containing 6% O2. The characteristics of the modified catalysts were analyzed using BET, TEM and XRD. The results of the experiment reveal that Na addition can significantly affect the properties of Rh/Al2O3 catalysts on the BET surface area and Rh metal dispersion. Furthermore, Na addition was found to significantly enhance the NO conversion of Rh/Al2O3 at 250–350 °C. On the contrary, Cu, Ni, and Co addition was found to have slight suppression effects. 相似文献
2.
Bing-Shun HuangMing-Yen Wey 《International Journal of Hydrogen Energy》2011,36(16):9479-9486
The effect of calcination temperature on the properties and H2 production ability of nitrogen-doped (N-doped) titanium dioxide (TiO2) photodeposited with 0.2 wt% Pt (platinum) was studied. The increase in crystallinity of pre-calcinated N-doped TiO2 initiated at temperatures higher than 131 °C transformed the morphology from anomalous nanostructure to texture composed of nanoparticles and enhanced the specific surface areas. At 200-400 °C, the anatase peaks gradually became sharper and the visible light absorption region decreased due to the growth of crystallites and the decrease of N-doping content, respectively. Maximum H2 production was reached when N-doped TiO2 was calcined at 200 °C followed by Pt photodeposition. The maximum condition is brought about by the formation of textures consisting of nanoparticles and a broad absorption region, thus creating superior active sites for photocatalytic H2 production. 相似文献
3.
SO2 and HCl are major pollutants emitted from waste incineration processes. Both pollutants are difficult to remove completely and can enter the catalytic reactor. In this work, the effects of SO2 and HCl on the performance of Rh/Al2O3 and Rh-Na/Al2O3 catalysts for NO removal were investigated in simulated waste incineration conditions. The characterizations of the catalysts were analyzed by BET, SEM/EDS, XRD, and ESCA. Experimental results indicated the 1%Rh/Al2O3 catalyst was significantly deactivated for NO and CO conversions when SO2 and HCl coexisted in the flue gas. The addition of between 2 and 10 wt.% Na promoted the activity of the 1%Rh/Al2O3 catalyst for NO removal, but decreased the CO oxidation and BET surface area. The catalytic activity for NO removal was inhibited by HCl as a result of the formation of RhCl3. Adding Na to the Rh/Al2O3 catalyst decreased the inhibition of SO2 because of the formation of Na2SO4, which was observed in the XRD and ESCA analyses. SEM mapping/EDS showed that more S was residual on the surface of the Rh-Na/Al2O3 catalyst than Cl. 相似文献
4.
P McLaughlin AJ Grillo-López BK Link R Levy MS Czuczman ME Williams MR Heyman I Bence-Bruckler CA White F Cabanillas V Jain AD Ho J Lister K Wey D Shen BK Dallaire 《Canadian Metallurgical Quarterly》1998,16(8):2825-2833
PURPOSE: The CD20 antigen is expressed on more than 90% of B-cell lymphomas. It is appealing for targeted therapy, because it does not shed or modulate. A chimeric monoclonal antibody more effectively mediates host effector functions and is itself less immunogenic than are murine antibodies. PATIENTS AND METHODS: This was a multiinstitutional trial of the chimeric anti-CD20 antibody, IDEC-C2B8. Patients with relapsed low grade or follicular lymphoma received an outpatient treatment course of IDEC-C2B8 375 mg/m2 intravenously weekly for four doses. RESULTS: From 31 centers, 166 patients were entered. Of this intent-to-treat group, 48% responded. With a median follow-up duration of 11.8 months, the projected median time to progression for responders is 13.0 months. Serum antibody levels were sustained longer after the fourth infusion than after the first, and were higher in responders and in patients with lower tumor burden. The majority of adverse events occurred during the first infusion and were grade 1 or 2; fever and chills were the most common events. Only 12% of patients had grade 3 and 3% grade 4 toxicities. A human antichimeric antibody was detected in only one patient. CONCLUSION: The response rate of 48% with IDEC-C2B8 is comparable to results with single-agent cytotoxic chemotherapy. Toxicity was mild. Attention needs to be paid to the rate of antibody infusion, with titration according to toxicity. Further investigation of this agent is warranted, including its use in conjunction with standard chemotherapy. 相似文献
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Christian L.A. Sze Wey Chua Tian Yeong Sim Ling Xiang Liu 《IEEE transactions on instrumentation and measurement》2001,50(2):259-262
We have measured the hysteresis in output voltage arising from loss of power for three Fluke 732B dc voltage references. Continuously powering the internal temperature-controlled oven provides the best accuracy with such Zener-diode-based dc voltage references. Batteries are used to provide power continuity when shipping between laboratories. We have shown that for these particular instruments, an apparent hysteresis induced by humidity is likely to dominate any hysteresis arising from loss of battery power when transit between laboratories takes three days or more. Our conclusion is that as much, if not more, care needs to be taken when dealing with humidity than with loss of battery power when shipping between laboratories. When the highest accuracy of dc voltage comparison is required, it becomes necessary to apply voltage corrections using the measured values of humidity coefficients and the relative humidity occurring during transit 相似文献
8.
Wey Yang Teoh Frans Denny Rose Amal Donia Friedmann Lutz Mädler Sotiris E. Pratsinis 《Topics in Catalysis》2007,44(4):489-497
A comparative photocatalytic analysis was carried out on TiO2 made in a Flame Spray Pyrolysis (FSP) process and flame-made Degussa P25. Both have similar crystallinity, phase composition,
phase segregation and a non-porous surface. Hence comparison was made based on their difference in specific surface area,
organic adsorption and the amount of OH• generated upon illumination. The photocatalytic activity tests were carried out using
the following series of organic compounds: sucrose, glucose, fructose, maleic acid, glyoxylic acid, oxalic acid, isobutyric
acid, phenol and methanol. FSP-made TiO2 outperformed P25 for saccharides mineralisation, while for phenol and methanol mineralisation P25 was better than FSP-made
TiO2. Similar mineralisation rates were observed for both FSP-made and P25 TiO2 for the mineralisation of carboxylic acids. This shows that the relative performance of the photocatalysts depends on the
type of organic compounds to be degraded. The high surface area and possibly a more efficient interfacial charge transfer
of FSP-made TiO2 provided an efficient pathway for saccharides mineralisation. As for phenol and methanol, the mineralisation rates were higher
when using P25 due to the greater amount of OH• radicals generated by this photocatalyst. The fast mineralisation rates of
carboxylic acids made degradation of these organic compounds to be less affected by the TiO2 photocatalyst properties and conditions tested in this work. 相似文献
9.
Phase transformation and morphology evolution of ZrO2/Al2O3/ZrO2 laminate induced by the post-deposition NH3 annealing at 480 °C were studied and the effect on the electrical property of the TiN/ZrO2/Al2O3/ZrO2/TiN capacitor module was evaluated in dynamic random access memory cell. Experimental results indicated N could indeed be incorporated into the dielectric laminate by the low-temperature NH3 annealing, resulting in tetragonal-to-cubic phase transformation and small crystallites in the ZrO2 layers. The C residue and Cl impurity in the ZrO2/Al2O3/ZrO2 laminate, which derived from the dielectric film formation and capping TiN layer deposition, respectively, could also be reduced by the nitridation process. As a result of the better surface morphology and less impurity content, lower dielectric leakage current and longer reliability lifetime were observed for the nitrided ZrO2/Al2O3/ZrO2 capacitor. This study demonstrates the low-temperature NH3 annealing on ZrO2/Al2O3/ZrO2 dielectric can be applicable to the metal-insulator-metal capacitor structure with nitride-based electrode, which brings advantages over mass production-wise property improvements and extends the practical applicability of the ZrO2/Al2O3/ZrO2 dielectric. 相似文献
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