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981.
用磁控溅射方法制各纯Fe薄膜,并硫化合成FeS2. 采用同步辐射X射线近边吸收谱与X射线光电子能谱研究了薄膜的电子结构. 结果表明,合成的FeS2薄膜,在费米能级附近,有较强的Fe 3d态密度存在,同时,在价带谱中2—10eV处有强度较大的S 3p态密度存在;Fe的3d轨道在八面体配位场作用下分别为t2g和eg轨道,实验中由Fe的吸收谱计算得到两分裂能级之差为2.1eV;实验测得FeS2价带结构中导带宽度约为2.4eV,导带上方仍存在第二能隙,其宽度约为2.8eV.
关键词:
磁控溅射
二硫化铁
X射线吸收近边结构
电子结构 相似文献
982.
重力场中的大气处于非平衡态,其温度是空间的函数,不同的等温面之间要产生热流,从而改变熵的空间分布。本文推导出重力场中的熵产生公式,并描绘出熵产生随高度变化的近似曲线。 相似文献
983.
The recognition capabilities of two molecular receptors 2,7-di(3′-pyridyl)-1,8-naphthyridine (DPN) and 2,7-di(3′-quinolyl)-1,8-naphthyridine (DQN) toward monosaccharides in chloroform were evaluated. Both DPN and DQN possess a naphthyridine core moiety, in which two pyridinic nitrogen atoms serve as the proton acceptors. Attached to the C2 and C7 positions of naphthyridine are two identical arms, each of which consists of pyridine (DPN) or quinoline (DQN) moiety that also acts as the proton acceptor. The arrangement of hydroxyl groups in monosaccharides offers the proton donors complementary to the proton acceptors of DPN (or DQN) to form a quadruply hydrogen bonds complex. The binding processes were studied by UV-vis, fluorescence and 1H NMR spectrophotometric titrations as well as electrospray ionization mass spectroscopy. The binding strength between DPN (or DQN) and examined monosaccharides was comparable to that for many other hydrogen-bonding host molecules previously reported. 相似文献
984.
985.
986.
The problem of “rate of change” for fractal functions is a very important one in the study of local fields. In 1992, Su Weiyi has given a definition of derivative by virtue of pseudo-differential operators [Su W. Pseudo-differential operators and derivatives on locally compact Vilenkin groups. Sci China [series A] 1992;35(7A):826–36. Su W. Gibbs–Butzer derivatives and the applications. Numer Funct Anal Optimiz 1995;16(5&6):805–24. [2] and [3]]. In Qiu Hua and Su Weiyi [Weierstrass-like functions on local fields and their p-adic derivatives. Chaos, Solitons & Fractals 2006;28(4):958–65. [8]], we have introduced a kind of Weierstrass-like functions in p-series local fields and discussed their p-adic derivatives. In this paper, the 3-adic Cantor function on 3-series field is constructed, and its 3-adic derivative is evaluated, it has at most order. Moreover, we introduce the definition of the Hausdorff dimension [Falconer KJ. Fractal geometry: mathematical foundations and applications. New York: Wiley; 1990. [1]] of the image of a complex function defined on local fields. Then we conclude that the Hausdorff dimensions of the 3-adic Cantor function and its derivatives and integrals on 3-series field are all equal to 1.There are various applications of Cantor sets in mechanics and physics. For instance, E-infinity theory [El Naschie MS. A guide to the mathematics of E-infinity Cantorian spacetime theory. Chaos, Solitons & Fractals 2005;25(5):955–64. El Naschie MS. Dimensions and Cantor spectra. Chaos, Solitons & Fractals 1994;4(11):2121–32. El Naschie MS. Einstein’s dream and fractal geometry. Chaos, Solitons & Fractals 2005;24(1):1–5. El Naschie MS. The concepts of E infinity: an elementary introduction to the Cantorian-fractal theory of quantum physics. Chaos, Solitons & Fractals 2004;22(2):495–511. [9], [10], [11] and [12]] is based on random Cantor set which takes the golden mean dimension as shown by El Naschie. 相似文献
987.
Jing Yang Xiao-Min Zhang Dong-Xia Hu Wen-Yi Wang Jing-Qin Su Feng Jing Sheng-Zhi Zhao 《Optics & Laser Technology》2007,39(1):123-128
We have discussed the optical and laser properties of different laser glass types. According to the properties of the gain and the B integral in the high-power laser amplifier chain, an optimal configuration is pointed out to improve the output capability at short pulses based on reducing nonlinear refractive index n2. In this way, high gain glasses and low n2 glasses are used in different amplifier stages simultaneously. The simulated results show that on the condition that the maximal output energies of both the configurations are same at 3 and 5 ns, the maximal output capability growth ratio of 30.48% () and 42.24% () for the optimal configuration can be obtained at 1 ns, respectively. 相似文献
988.
We employ angle-resolved photoemission to characterize the electronic band structure of the Pb "nanowire" array self-assembled on a stepped Si(111) surface. Despite the highly oriented nanowires observed in scanning tunneling microscopy images, we find essentially two-dimensional Fermi contours modulated one dimensionally perpendicular to the wires. This strong two-dimensional and quasi-one-dimensional nature of the band structure explains the stability and anisotropy of the metallic phase down to 4 K as reported recently. A simple tight-binding model with each Si nanoterrace covered by a densely packed Pb overlayer successfully reproduces this modulated band structure and quantifies the electron coupling within the "nanostripes" and the step-edge potential. 相似文献
989.
Fei Su Yaofeng Sun Cheng Yun Audrey Wong Hui Leong Ho Xiaoqi Chen 《Optics and Lasers in Engineering》2007,45(12):1177-1185
We have developed an integrated optical system to measure the warpage of a microdisplay product at post-packaging die-attach temperature and to test its hermeticity after manufacturing. This system is constructed based on the principle of Twyman/Green (T/G) interferometry and Newton interferometry. T/G interferometry is used to characterize warpage of the microdisplay's base-plate, while Newton interferometry is used to characterize the gap variance between face-plate and base-plate of the microdisplay. With these measurements, deformation and shape of the microdisplay can be comprehensively determined during its manufacturing process, which is critical for its quality test and reliability evaluation. Delicate mechanical system was designed to facilitate the optics integration and alignment. To evaluate the performance of the optical system itself, warpage of a sample was re-measured with Tailor–Hobson profilometer whose resolution is 10 nm, the results from these two testing systems agree well with each other. Some application examples of the integrated testing system were presented to verify its work efficiency. 相似文献
990.
Weimin Hou Li Chen Maoyou Yang Mingjian Zhang Junmei Wang Jiakuo Shi Shuo Su Duo Zhang Hongping Wu 《Annalen der Physik》2023,535(7):2300061
Based on the first-principles calculation, the effect of intercalated LiF on the contact characteristics of the interface between Au electrode and MoS2 layer is studied. It is found that adding LiF film can change the contact type between metal electrode Au and MoS2 layer from Schottky contact to ohmic contact, which is accompanied by interfacial charge transfer from LiF layer to MoS2 layer and the downward movement of d (dxy and dz2) orbital of Mo atom and p (px and py) orbital of S atom to Fermi level. And the interlayer spacing between LiF layer and Au electrode has a great impact on the interface contact characteristics. The electric field effect and stress effect of interface contact of Au, LiF and MoS2 (Au/LiF/MoS2)is more obvious than that of interface contact of Au and MoS2 (Au/MoS2). Au/LiF/MoS2 shows ohmic contact with the interlayer spacing between Au layer and LiF layer less than 3.05 Å and with the electric field less than 0.15 VÅ−1, respectively, while Au/MoS2 still shows N-type Schottky contact. These findings are helpful to control the contact resistance and have guiding significance for high performance MoS2 field effect transistor and other electronic components. 相似文献