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101.
Electronic Transport of the Adsorbed Trigonal Graphene Flake: A First Principles Calculation 下载免费PDF全文
In recent years, electronic transport through molecular devices has attracted much attention due to the progress in experimental techniques for ma- nipulating individual molecules and the availabil- ity of the first-principles method to describe the elec- trical properties of devices. Graphene, a two- dimensional (2D) network of sp2 hybridized carbon atoms, has stimulated great research interest due to its unique electronic transport properties and its pro- found potential for future device applications. Chemical doping with foreign atoms is generally cho- sen to modify the electronic transport properties of carbon materials. The possibility of functionalizing graphene with radicals such as O, F, and H atoms has been experimentally demonstrated. One- dimensional GNRs and zero-dimensional graphene quantum dots (GQDs), including triangular, rectangular and hexagonal shapes, which can be ob- tained through the geometry cutting method, pro- vide the possibility to explore low-dimensional trans- port properties for carbon-based nanoelectronics. The trigonal graphene flake (TGF), a kind of representa- tive zero-dimensional GQD, is prominent in electronic and magnetic properties due to its n-fold degenerated half-filled zero-energy states. This novel property was revealed by both experimental and theoretical studies. 相似文献
102.
分析了捷联惯性导航系统姿态解算中不可交换性误差产生原因,提出并分析了一种旋转矢量误差估计模型,并从该模型出发推导了几种高精度的捷联姿态算法,提出了由角速度提取角增量的梯形算法。以船舶为应用对象,进行了数字仿真和算法精度分析比较,结果表明:等效旋转矢量法和梯形算法可以提高系统的姿态解算精度。 相似文献
103.
Hadronic Decays of the Spin-Singlet Heavy Quarkomium under the Principle of Maximum Conformality 下载免费PDF全文
The principle of maximum conformality (PMC) provides a way to eliminate the conventional renormalization scale ambiguity in a systematic way. By applying the PMC scale setting, all non-conformal terms in a perturbative series are summed into the running coupling, and one obtains a unique, scale-fixed prediction at any finite order. In this study, we make a detailed PMC analysis for the spin-singlet heavy quarkoniums decay (into light hadrons) at the next-to-leading order. After applying the PMC scale setting, the decay widths for all those cases are ahnost independent of the initial renormalization scales. The PMC scales for ηc and he decays are below 1 GeV; to achieve a confidential pQCD estimation, we adopt several low-energy running coupling models to carry out the estimation. By taking the MPT model, we obtain Г(ηc → LH) = 25.09 -4.28^+5.52 MeV, F(ηb →LH) 14.34-0.84^+0.92 feV, Г(hc →LH) = 0.54-0.04^+0.06 MeV and Г(hb →LH) = 39.89-0.46^+0.28 keV, where the errors are calculated by taking mc E[1.4OGeV, 1.60GeV] and mb C[4.50GeV, 4.70GeV]. These decay widths agree with the principle of minimum sensitivity estimations, in which the decay widths of ηc,b are also consistent with the measured ones. 相似文献
104.
<正>反比例函数y=k x中,我们印象最深的莫过于其图像上的每一点对x轴、y轴所构成的矩形的面积相等,都为|k|,就是这条重要特性,我们还可以提示出反比例函数图像的另外两个特征.图1我们知道反比例函数图像关于原点中心对称,直线与反比例函数图像交于A,B两点,若直线AB过原点时,则必有OA=OB.如图1.那么,若直线AB不过原点,还会有相等的情况吗?首先,在平面几何中,我们知道如下基本性质. 相似文献
105.
采用分步合成法成功合成了CdS-ZnSe(Ⅰ型)和CdSe-ZnS(Ⅱ型)核-壳结构量子点.并首次构建了CdS-ZnSe/CdSe-ZnS结构F(o)rster能量转移对.利用吸收光谱(UV-Vis),光致发光谱(PL),时间分辨光致发光谱(TRPL),透射电子显微镜(TEM)对比研究了不同配比的CdS-ZnSe/CdSe-ZnS结构Fö rster能量转移.分析结果表明:在能量转移发生时,CdS-ZnSe荧光强度显著下降,荧光寿命明显缩短,F(o)rster能量转移确实存在于CdS-ZnSe/CdSe-ZnS量子点之间. 相似文献
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108.
Using the US National Aeronautics and space Administration (NASA) Earth Observing-1 Mission (EO-1) hyperion hyperspectral remote sensing data, we study the shallow-water bathymetry inversion in Smith Island Bay. The fast line-of-sight atmospheric analysis of spectral hypercubes module is applied for atmospheric correction, and principal component analysis method combined with scatter diagram and maximum likelihood classification is used for seabed classification. The diffuse attenuation coefficient Kd is derived using quasi-analytical algorithm (QAA), which performs well in optically deep water. Kd obtained from QAA requires correction, particularly those derived in some coastal areas with optically shallow water and calculated by direct inversion based on radiative transfer theory to obtain the bathymetry. The direct inversion method derives the water depth quickly, and matches the results from optimized algorithm. 相似文献
109.
IC用高纯试剂中金属杂质分析 总被引:6,自引:0,他引:6
对HCl,HF和HNO3三种MOS级高纯试剂中18种金属杂质用发射光谱进行分析研究,取20ml样品,加入适量甘露醇络合硼杂质,在有机玻璃防尘罩内低温挥发基体富集杂质,最后将杂质溶液转移到一对平头电极上,用电弧光谱进行测定。检测限为0.2-4.0(ng/ml),加入标准的回收率绝大部分在90%以上。 相似文献
110.
从高考阅卷的角度谈规范化解题 总被引:1,自引:0,他引:1
高考答题的规范化要求有很多方面:答题工具、答题规则与程序、答题位置、答题过程及书写格式要求等等.了解高考答题要求和阅卷教师的一些心态,养成良好的答题习惯,可以帮助学生在高考中多得分,至少不会失去一些应得分. 相似文献