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计算了不同Al掺杂浓度下ZnO体系电子结构和光学属性.分析了掺杂对AZO(ZnO:A1)晶体结构、能带、态密度、光学性质的影响.所有计算都是基于密度泛函理论框架下的第一原理平面波赝势方法.计算结果表明:Al掺杂ZnO在导带底引入了大量由掺杂原子贡献的导电载流子,明显提高了体系的电导率.费米能级进入导带.同时,光学性质的计算表明光学带隙明显展宽,且向低能方向漂移;AZO透明导电材料的光学透过率在可见光范围内高达85%,紫外吸收限随着掺杂浓度的增加而发生蓝移.所有计算表明AzO材料可作为优良的透明导电薄膜材料.  相似文献   
2.
Well-confined uniform polyaniline (PANI) nanofibers were synthesized by using photo-assisted chemical oxidative polymer- ization of aniline in the presence of different dopant acids,and the radical scavenging ability of the produced PANI nanofibers was determined by the DPPH assay.It was found that the antioxidant activity of PANI nanofibers was higher than conventional PANI, and increased with decreasing of averaged diameter of the nanofibers.The enhanced antioxidant activity was concerned with increased surface area of PANI nanofibers.  相似文献   
3.
钾搀杂对叠氮化亚铜晶体能带结构影响的DFT研究   总被引:1,自引:0,他引:1  
朱卫华  张效文  卫涛  肖鹤鸣 《中国化学》2008,26(12):2145-2149
运用广义梯度近似(GGA)密度泛函理论(DFT)方法对钾搀杂叠氮化亚铜晶体的原子和电子结构以及缺陷形成能进行了研究。结果表明,钾搀杂破坏了叠氮酸根的对称性,导致不对称的原子位移。随着搀杂钾浓度的增加,搀杂叠氮化亚铜晶体的带隙逐渐增大。热力学上,杂质钾很容易被搀杂到叠氮化亚铜晶体中,而且钾还充当了缺陷团簇的成核中心。最后,从电子结构角度理解了搀杂钾浓度对叠氮化亚铜晶体感度的影响。  相似文献   
4.
Bismuth-promoted (1% and 3%) vanadyl pyrophosphate catalysts were prepared by refluxing Bi(NO3)3·5H2O and VOPO4·2H2O in isobutanol. The incorporation of Bi into the catalysts lattice increased the surface area and lowered the overall V oxidation state. Profiles of temperature programmed reduction (TPR) in H2 show a significant shift of the maxima of major reduction peaks to lower temperatures for the Bi-promoted catalysts. A new peak was also observed at the low temperature region for the catalyst with 3% of Bi dopant. The addition of Bi also increased the total amount of oxygen removed from the catalysts. The reduction pattern and reactivity information provide fundamental insight into the catalytic properties of the catalysts. Bi-promoted catalysts were found to be highly active (71% and 81% conversion for 1% and 3% Bi promoted catalysts, respectively, at 703 K), as compared to the unpromoted material (47% conversion). The higher activity of the Bi-promoted catalysts is due to that these catalysts possess highly active and labile lattice oxygen. The better catalytic performance can also be attributed to the larger surface area.  相似文献   
5.
聂海  张波  唐先忠 《中国物理》2007,16(3):730-734
This paper reports that the polymer/organic heterojunction doped light-emitting diodes using a novel poly-TPD as hole transport material and doping both hole transport layer and emitter layer with the highly fluorescent rubrene and DCJTB has been successfully fabricated. The basic structure of the heterostructure is PTPD/Alq3. When hole transport layer and electron transport layer are doped simultaneously with different dopant, the electroluminescence quantum efficiencies are about 3 times greater than that of the undoped device. Compared with undoped device and conventional TPD/Alq3 diode, the stability of the doping device is significantly improved. The process of emission for doped device may include carrier trapping as well as F\"{o}rster energy transfer.  相似文献   
6.
搀杂六铝酸盐LaMxAl12-xO19+δ上甲烷催化燃烧研究   总被引:4,自引:1,他引:4  
采用共沉淀法制备了系列金属Mn搀杂的六铝酸盐LaMnxAl12-xO19+δ(x分别为0, 0.5, 1.0, 1.5, 2.0, 5.0)催化剂, 采用BET, TG-DTA, XRD进行了物性表征, 并以甲烷催化燃烧为目标反应, 研究了Mn搀杂量对催化剂活性的影响. 结果表明 LaAl12O19+δ催化活性较低, 随着Mn的引入, 催化活性逐步提高. 当x=1.5时, 催化活性达到最大值, 为理想搀杂量. 焙烧温度对晶型及催化活性有重要影响, 1200 ℃时可以形成完整的六铝酸盐晶型, 并具较高的催化性能. 所得较好催化剂起燃温度T10%为418 ℃, T90%为663 ℃.  相似文献   
7.
pacc:7850E Thegeneralcharacteristicsoff-fandf-d emissionspectraoflanthanideionsininsulators arediscussed.Thecurrentstatusofenergylevel andintensitycalculationsisevaluated.Taking typicalexamples,themethodsofsynthesisoflan thanideion-dopedinsulatingnanomate…  相似文献   
8.
Several Mo-V-Te-O mixed metal oxides catalysts with different dopant were prepared and used for catalytic oxidation propane to acrolein. It was revealed that the addition of P could greatly improve the performance of the Mo-V-Te-O catalyst. The catalysts were examined by XRD and H2-TPR. The XRD characteristic of the Mo-V-Te-P-O showed that the addition of P could aggrandize the (V0.07Mo0.93)5O14 phase. H2-TPR illuminated that the MoV0.3Te0.23P0.15On catalyst took on the best redox ability.  相似文献   
9.
The TiO2, MoO3, PEO doped four-member tungstic acid sols were prepared for the first time. The stability of different doped content sols were investigated and optimized with rotational viscometer. The four-member doped tungstic acid sol was very stable which could be stored more than two months at room temperature. The WO3 electrochromic film prepared from this doped four-member tungstic acid sol had excellent performance and longevity of service.  相似文献   
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