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61.
Well crystallized and homogeneous LiFePO4/C (LFPO) thin films have been grown by pulsed laser deposition (PLD). The targets were prepared by the sol-gel process at 600 °C. The structure of the polycrystalline powders was analyzed with X-ray powder diffraction (XRD) data. The XRD patterns were indexed having a single phase olivine structure (Pnma). LFPO thin films have been deposited on three different substrates: aluminum (Al), stainless steel (SS) and silicon (Si) by pulsed laser deposition (PLD). The structure of the films was analyzed by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). It is found that the crystallinity of the thin films depends on the substrate temperature which was set at 500 °C. When annealed treatments were used, secondary phases were found, so, one step depositions at 500 °C were made.Stainless steel is demonstrated to be the best choice to act as substrate for phosphate deposition. LiFePO4 thin films grown on stainless steel plates exhibited the presence of carbon, inducing a slight conductivity enhancement that makes these films promising candidates as one step produced cathodes in Li-ion microbatteries. 相似文献
62.
Dr. Yogesh Somasundar Iris C. Lu Dr. Matthew R. Mills Lisa Y. Qian Ximena Olivares Prof. Dr. Alexander D. Ryabov Prof. Dr. Terrence J. Collins 《Chemphyschem》2020,21(11):1083-1086
Understanding the catalysis of oxidative reactions by TAML activators of peroxides, i. e. iron(III) complexes of tetraamide macrocyclic ligands, advocated a spectrophotometric procedure for quantifying the catalytic activity of TAMLs for colorless targets (kII′, M−1 s−1), which is incomparably more advantageous in terms of time, cost, energy, and ecology than NMR, HPLC, UPLC, GC-MS and other similar techniques. Dyes Orange II or Safranin O (S) are catalytically bleached by non-excessive amount of H2O2 in the presence of colorless substrates (S1) according to the rate law: −d[S]/dt=kIkII[H2O2][S][TAML]/(kI[H2O2]+kII[S]+kII′[S1]). The bleaching rate is thus a descending hyperbolic function of S1 : v=ab/(b+[S1]). Values of kII′ found from a and b for phenol and propranolol with commonly used TAML [FeIII{o,o′-C6H4(NCONMe2CO)2CMe2}2(OH2)]+ are consistent with those for S1 (phenol, propranolol) obtained directly by UPLC. The study sends vital messages to enzymologists and environmentalists. 相似文献
63.
《International Journal of Infrared and Millimeter Waves》2007,28(10):821-829
This work presents a fullwave analysis for annular ring microstrip antennas on uniaxial anisotropic substrates. The effect
of the anisotropic substrates on the antenna performance at the millimeter wave band is investigated. The analysis is performed
in the Hankel transform domain using Hertz vector potentials and Galerkin Method. Numerical results are presented for the
antenna main characteristics such as resonant frequency and radiation pattern. 相似文献
64.
Sheng-Po Chang Shoou-Jinn Chang Chien-Yuan Lu Yu-Zung Chiou Ricky W. Chuang Hung-Chieh Lin 《Journal of Crystal Growth》2009,311(10):3003-3006
Nitride-based metal–semiconductor–metal ultraviolet (UV) photodetectors prepared on Si (1 1 1) substrate with stacked buffer layers were proposed and prepared. With 5 V applied bias, it was found that dark current of the fabricated device was only 7.95×10−12 A. With an applied bias of 10 V, it was found that peak responsivity was 0.06 A/W, corresponding to quantum efficiency of 21.2% while UV/visible rejection ratio was 244. With 5 V applied bias, it was found that noise equivalent power, NEP and detectivity, D*, of our detector were 1.70×10−13 W and 1.18×1013 cm Hz0.5 W−1, respectively. 相似文献
65.
表面抛光可能给K9基片带来额外的杂质和吸收,分离K9基片的表面吸收率与体吸收率有助于改进基片的加工质量和抛光工艺,对抗损伤能力研究具有重要意义。分析了激光量热法测量弱吸收的原理,采用符合ISO 11551要求的激光量热计测量K9基片的弱吸收。对相同工艺抛光的不同厚度K9基片进行了弱吸收表征,实验发现K9基片的弱吸收随着厚度增加近似线性增大。推导了表面吸收率和体吸收率的计算式,实验得出本样品的表面吸收率为1.2110-5,体吸收率远大于表面吸收率,体吸收系数为1.7210-3/cm。实验结果显示所用K9样品的吸收主要来自于材料本身,改善抛光工艺对降低其吸收率作用不大。 相似文献
66.
Daniela Bertacchi Giambattista Giacomin 《Bulletin of the Brazilian Mathematical Society》2003,34(3):401-415
We analyze a model of an interface fluctuating above a
rough substrate. It is based on harmonic crystals, or lattice
free fields, indexed by d ,
d 3. The phenomenon for
which we want to get precise quantitative estimates is the
repulsion effect of the substrate on the interface: the
substrate is itself a random field, but its randomness is
quenched (this generalizes
the widely considered case of a flat deterministic substrate).
With respect to [2] in which the substrate has been taken to be
an IID field, here the substrate is an harmonic crystal, as the
interface, and as such it is strongly correlated. We obtain the
leading asymptotic behavior of the model in the limit of a very
extended substrate: we show in particular that, to leading
order, the effect of an IID substrate cannot be distinguished
from the effect of an harmonic crystal substrate. We observe
however that, unlike in the IID substrate case, annealed and
quenched models display sharply different features. 相似文献
67.
《Arabian Journal of Chemistry》2022,15(12):104315
The green and high-value recycling of shrimp shell and straw remains a worldwide problem. This study aimed to investigate the potential utilization of a fermentation broth (FB) which contains shrimp shell and straw as a new source for preparation of biodegradable films. Aureobasidium pullulans and Photobacterium sp. LYM-1 were used in the fermentation. The cellulase activity was 115.92 U/mL and chitinase activity was 17.89 U/mL in FB. The polysaccharides concentration in FB was 1.05 mg/mL after 7 days of fermentation. An eco-friendly PVA-reinforced FB biodegradable film (FBBF) was successfully prepared and the effect of different plasticizers and surfactants on the mechanical, structural, and impermeability properties of the film was determined. The formation of new bonds between PVA and FB was proved by FTIR spectroscopy. The FBBF containing 0.25 % (w/v) glycerol and 0.01 % (v/v) tween-20 showed better strength properties. Elongation and water-swelling properties were highly improved by adding 0.2 % (m/v) citric acid. According to FE-SEM images, the smooth and tight surface of citric acid added FBBF was observed. Interestingly, the FBBF film showed good heat/moisture capacity, antifungal, and degradation properties. This report reveals a new green, and high-value recycling of straw and shrimp shell by the co-fermentation with A. pullulans and Photobacterium sp. LYM-1. It is also a novel way for the preparation of biodegradable film. 相似文献
68.
Systematic calculations of the structures of the H2CO, F2CO, Cl2CO, HClCO, HFCO, and FClCO molecules in the S0 and T1 states were performed using the B3LYP and MP2 methods with different AO basis sets and also at the CCSD(T)/cc-pV(T+d)Z level
of theory. The saturation of the correlation consistent sequence of basis sets cc-pV(N+d)Z (N = D, T, Q, and 5) and aug-cc-pV(N+d)Z
(N = D, T, and Q) was studied. Recommendations for choosing the calculation method are given. The relativistic corrections
were estimated. The influence of the number and type of halogen atoms on the geometric parameters of the molecules in the
S0 and T1 states and the heights of inversion barriers in the T1 state was investigated.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2625–2635, December, 2005. 相似文献
69.
L. Yu Y. Krockenberger Ingo Fritsch H.-U. Habermeier 《Progress in Solid State Chemistry》2007,35(2-4):545-551
NaxCoO2 [x = 0.51, 0.54, and 0.59] thin films have been grown on SrTiO3 (100)-oriented single crystals with a 5° vicinal cut towards [010] by pulsed laser deposition. We analysed the films by X-ray diffractometry, atomic force microscopy (AFM), and dc-transport measurements. X-ray diffraction patterns of the films show single phase and c-axis textured growth with the film plane closely aligned to the [001]-direction of 5° miscut SrTiO3 (001) substrates. In addition to the structural analysis of these films we performed transport measurements along and perpendicular to the substrate tilt direction and determined the resistivity anisotropy as a function of temperature. The results enable the development of a strategy for the fabrication of NaxCoO2 based thermoelectric thin film devices. 相似文献
70.