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1-xS Ternary Compound Thin Films
Published in R D Tomlinson, A E Hill, R D Pilkington, Ternary and Multinary Compounds, 2020
Ryo Inoue, Masahiko Kitagawa, Takayoshi Nishigaki, Kunio Ichino, Hiroshi Kobayashi, Masakazu Ohishi, Hiroshi Saito
The film thickness was measured by optical interference. The film thickness was fixed at about 2 µm/h. The composition x of the ZnxMg1-xS:Mn thin films has been determined by energy dispersive X-ray (EDX) analysis. The lattice constant is estimated by X-ray Diffraction (XRD) measurement using Cu-Kα(λ=1.5418A) radiation. Optical absoption edge was estimated by α-hv plot from the optical transmission spectra. Photolummescence (PL) and photoluminescence excitation (PLE) spectra were measured using a deuterium lamp as an excitation source.
Miscellaneous
Published in Dan Zwillinger, CRC Standard Mathematical Tables and Formulas, 2018
b2=bTb $ \left\| b \right\|_{2} = \sqrt {b^{T} b} $ . The size of the basis, in the full rank case, is the volume det(BTB) $ \sqrt { {\text{det }}(B^{T} B)} $ . This is constant for a given lattice (up to sign) and is called the lattice constant. The figure shows a lattice with basis V=[v1v2] $ V = [v_{1} v_{2} ] $ and a “shorter”basis U=[u1u2]. $ U = [u_{1} u_{2} ]. $
not metals
Published in DAVID K. FERRY, Semiconductor Transport, 2016
In all of the discussion above, it was assumed that the alloy can be grown lattice matched to a suitable substrate. Is this what one wants to do? Certainly, it has been argued that one should try to lattice match the heterojunction interface so as not to introduce defects and dislocations arising from release of local strain. On the other hand, it has been found in non- lattice-matched heterostructures that there is a critical thickness of the overgrown layer, below which the strain is not released. Rather, the grown layer is distorted so that its lattice constant along the interface matches the substrate. This results in a distortion of the basic cubic cell in that the cell is compressed (extended) along the interface and therefore is extended (compressed) in the direction normal to the interface (or vice versa depending upon which lattice constant is larger). Yet these layers can be grown quite easily with modem growth techniques such as molecular-beam epitaxy or metal- organic vapor-phase epitaxy. The resulting "strained-layer heterojunction" is a high-quality interface in which the lattice of the grown layer is purposely mismatched to that of the substrate. The layer can be grown as long as it is sufficiently thin (here, this is usually thought to be of the order of 20 nm or less) (Matthews and Blakeslee, 1974). The reason for doing this lies in the dependence of the band structure on the lattice constant. The built-in strain modifies the band structure to produce desirable properties as part of the overall concept of band-gap engineering.
Bandgaps and topological interfaces of metabeams with periodic acoustic black holes
Published in Mechanics of Advanced Materials and Structures, 2022
Figure 1(c) exhibits the geometric details of the unit cell for MODEL I. The unit cell is symmetrical with respect to the and and represents the lattice constant. Each curve of the ABH branch is driven by the power law function In this analysis, the specific geometric parameters are set as: The ABH structure is made of steel with Young’s modulus of 210 GPa, Poisson’s ratio of 0.3, and the density of The material parameters are used in theoretical models and numerical analysis unless otherwise specified.
Research on preparation of nano-Sb2O3@Br-VERs core-shell composite particles
Published in Particulate Science and Technology, 2022
Jianlin Xu, Tao Wang, Shibo Ren, Chenghu Kang, Lei Niu, Jiliang Fan, Chengsi Li
Figure 1 displays the XRD spectrum of nano-Sb2O3 and its composite particles. The curve (a) in Figure 1 is the diffraction patterns of nano-Sb2O3. It can be seen from curve (a) that there are some feature diffraction peaks at 13.74°, 27.6°, 32.0°, 46.0° and 54.6° of 2-Theta corresponding to (111), (222), (400), (440) and (622) crystal planes of Sb2O3 with a face-centered cubic lattice. It shows the crystal structure of nano-Sb2O3 is face centered cubic crystal with lattice constant of 1.115 nm. The curve (b) and curve (c) in Figure 1 are the diffraction patterns of PhMe-nano-Sb2O3@Br-VERs and ST-nano-Sb2O3@Br-VERs composite particles, respectively. It can be seen from the two curves that the crystal structure of nano-Sb2O3 particles is not changed when Br-VERs and nano-Sb2O3 form composite particles. And the diffraction peak intensity of PhMe-nano-Sb2O3@Br-VERs composite particles is significantly lower than that of nano-Sb2O3, which indicates that there are some amorphous microstructures in the composite particles. However, the account of amorphous microstructures in ST-nano-Sb2O3@Br-VERs composite particles is lower, resulting in that the diffraction peak intensity of the composite particles does not change significantly compared with that of nano-Sb2O3 particles.
Improve the structure through pH-control to improve the photocatalytic performance of cubic silver phosphate photocatalyst
Published in Journal of Dispersion Science and Technology, 2022
Jin Wang, Yongfeng Cai, Hanxiao Du, Yi Shen, Fengfeng Li, Zuotao Liu, Yunfeng Liu, Chao Peng
To determine the crystal structure of the sample, an XRD phase analysis was performed. Figure 1 shows the XRD pattern of a series of Ag3PO4 photocatalyst. All the patterns can be indexed to cubic Ag3PO4 with the space group P-43n (No. 218) according to JCPDF card 06-0505. The high activity crystal surface and three major diffraction peaks of the Ag3PO4 photocatalyst can be obtained through XRD images. The lattice constant is calculated by MDI-jade software. The lattice constant is calculated by specifying the crystal system and inputting the crystal surface index of the corresponding peak. The lattice constant at the precise peak position can be calculated by the spectrum peak separation. Calculate the peak offset value according to the following formula: