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31.
在教育领域中,命名实体识别在机器自动提问和智能问答等相关任务中都有应用。传统的中文命名实体识别模型需要改变网络结构来融入字和词信息,增加了网络结构的复杂度。另一方面,教育领域中的数据对实体边界的识别要十分精确,传统方法未能融入位置信息,对实体边界的识别能力较差。针对以上的问题,该文使用改进的向量表示层,在向量表示层中融合字、词和位置信息,能够更好地界定实体边界和提高实体识别的准确率,使用BiGRU和CRF分别作为模型的序列建模层和标注层进行中文命名实体识别。该文在Resume数据集和教育数据集(Edu)上进行了实验,F1值分别为95.20%和95.08%。实验结果表明,该文方法对比基线模型提升了模型的训练速度和实体识别的准确性。  相似文献   
32.
高动态范围(high dynamic range,HDR)视频算法计算复杂度高,硬件实现需要大量逻辑和存储资源,且现有的算法难以满足高分辨率下的实时性要求.针对上述问题,提出一种优化的HDR视频流水线算法,同时利用FPGA的并行可重构特性,完成该算法的硬件实现.算法首先将相机响应函数内置于FPGA的查找表(look-up table, LUT)中,对3帧低动态范围(low dynamic range, LDR)图像进行合并,转换后的数据通过多路并行流水缓存在FPGA的BRAM中; 然后使用快速的全局色调映射算法将结果实时显示输出.最终算法在Xilinx Kintex-7开发板上实验通过,在120 MHz系统时钟频率下,对于1 920×1 080分辨率的视频流,处理速度达到65 f/s,满足了实时性要求.  相似文献   
33.
A cheap and magnetic Ni/Cu/Al/Fe catalyst for the selective hydrogenation of LA into GVL catalysts was prepared by sol-gel method. The reaction pathway was systematically studied by examining the reaction conditions, such as reaction pressure, catalyst loadings, water content, and reaction temperature. Higher reaction pressure and catalyst loadings were prior to form HA, then MHV, finally GVL; ML was easily to form with a higher reaction temperature. Water, as a key role, which was in favor to form HA, then MHV, finally GVL; more important, a higher LA conversion could be obtained in methanol as the solvent with some certain content of water. And, it can give a reference for future new clean energy vehicles' application.  相似文献   
34.
以新型磷羧酸共聚物RP-92(A)为主剂的复合水稳剂RP-92处理高盐水质的循环冷却水,实验室动态模拟试验结果为碳钢试管的腐蚀速率小于0.015mm/a,结垢粘附速率小于3.6mg/(cm2·月)。经现场8000h连续运行,现场监测换热器碳钢试管的平均腐蚀速率小于0.061mm/a,结垢粘附速率小于11.0mg/(cm2·月),且无孔蚀现象,处理效果优于传统无机聚磷配方,水中总磷含量也有较大幅度下降。RP-92经毒性评价,属低毒,对环境基本无影响。  相似文献   
35.
陶瓷涂层隔热无冷机的试验研究   总被引:2,自引:0,他引:2  
本文系统地介绍了6135无冷柴油机的研制过程,针对其无水冷却后出现的问题,采取了一系列措施,解决了工作可靠性问题并使发动机性能得到了明显的改善.  相似文献   
36.
37.
Finding cost-effective and efficient anode materials for solid oxide fuel cells (SOFCs) is of prime importance to develop renewable energy technologies. In this paper, La and Fe co-doped SrTiO3 perovskite oxide, La0.3Sr0.7Ti0.3Fe0.7O3?δ (LSTF0.7) composited with CeO2 is prepared as a composite anode by solution infiltration method. The H2 and CO oxidation behavior and the electrochemical performance (electrochemical impedance spectra, IV and IP curves) of the scandia-stabilized zirconia (ScSZ) electrolyte supported cells fabricated by tape casting with the LSTF0.7–CeO2 composite anode are subsequently measured at various temperatures (700–850 °C). Electrochemical impedance spectra (EIS) of the prepared cells with the LSTF0.7–CeO2|ScSZ|La0.8Sr0.2MnO3 (LSM)–ScSZ configuration illustrate that the anode polarization resistance distinguished from the whole cell is 0.072 Ω cm2 in H2, whereas 0.151 Ω cm2 in CO at 850 °C. The maximal power densities (MPDs) of the cell at 700, 750, 800 and 850 °C are 217, 462, 612, 815 mW cm?2 in H2 and 145, 349, 508, 721 mW cm?2 in CO, respectively. Moreover, a significant decrease of anode activation energy towards H2 oxidation is clearly demonstrated, indicating a better electrochemical performance in H2 than in CO. These results demonstrate an alternative composite anode with high electrocatalytic activity for SOFC practical applications.  相似文献   
38.
The changes in structure and the hardness of two electroless deposited Ni-P alloy coatings (with P content of 1.5 and 9.5 wt pct) with heat treatment have been studied by XRD and TEM. The deposits containing 1.5 wt pct P can be represented as an fcc NiP supersaturated solid solution of 5~10 nm microcrystallites. whereas the deposits containing 9.5 wt pct P are amorphous. The heat treatment process induces crystallization of amorphous Ni to Ni phosphides and fcc Ni.Both of the deposits reach maximum hardness after annealing at 400℃ for 1 h. All coated steel specimens are inferior in fatigue strength to uncoated steel specimens mainly due to the poor fatigue resistance of the coating itself  相似文献   
39.
In this paper, Ni/YSZ and Ni–CeO2/YSZ anodes for a solid oxide fuel cell (SOFC) were prepared by tape casting and vacuum impregnation. By this method, the Ni content in the anode could be reduced compared to the traditional tape casting method. It was found that adding CeO2 into the Ni/YSZ anode by a Ni(NO3)2 and Ce(NO3)3 mixed impregnation could further enhance cell performance. This was investigated in H2 at 1073 K. XRD patterns indicated that CeO2 and Ni were separate phases, and the CeO2 addition could enhance the Ni dispersion on the YSZ framework surface which was observed by SEM images. It was shown that adding CeO2 into the Ni anodes could decrease the cell polarization resistance. The maximum power density for cells with 25 wt.% Ni, 5 wt.% CeO2–25 wt.% Ni/YSZ, or 10 wt.% CeO2–25 wt.% Ni/YSZ anode was 230 mW cm−2, 420 mW cm−2 and 530 mW cm−2, respectively, in H2 at 1073 K. The OCV for these cells was 1.05–1.09 V, indicating that a dense electrolyte film was obtained by co-firing porous YSZ layer and dense YSZ layer.  相似文献   
40.
Bi2O3 doped BaFeO3?δ on the B-site as a cobalt free perovskite cathode for intermediate temperature solid oxide fuel cells is evaluated. The BaFe1?xBixO3?δ (BFBx) powders are synthesized by solid state reaction. It is found that Bi2O3 doping stabilizes the BaFeO3 cubic phase. The new cathode is compatible with Gd0.1Ce0.9O1.95 even calcined at 1000 °C for 10 h. The electronic conductivity shows a transformation from semiconductor to metal conductor, and achieves its maximum value of 28.1 S cm?1 for BFB10 at 800 °C. The δ is as high as 0.408 for BFB10 determined by iodometric titration. This leads to the free volume in crystal lattice of BFB10 21.60% higher than that of BaNb0.05Fe0.95O3?δ. The area specific resistance is only 0.133 Ω cm2 for BFB10 at 750 °C and the average TEC is 26.697 × 10?6 K?1 measured from room temperature to 800 °C. The peak power density of Ni-YSZ|YSZ|GDC|BFB10 cell is 646.28 mW cm?2 at 750 °C, higher than that of single cell using LSCF as cathode. These show that BFBx perovskite oxides with cubic phase are promising cathodes for intermediate temperature solid oxide fuel cells.  相似文献   
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