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Thin Li3±xPO4±yNzLi+- electrolyte films prepared by reactive rf-magnetron sputtering of Li3PO4 incorporate a certain amount of nitrogen which is made responsible for increased Li+-conductivity as well as at least kinetic stability with lithium metal. A possible change of the oxidation state +5 of phosphorus
as a result of the sputter process has not yet been considered for explanation. We have found out that it cannot be generally
assumed that reactive low power rf-magnetron sputtering of Li3PO4 results in fully oxidized films, even when pure O2 is employed as sputtering gas. Our films immediately react with H2O releasing a garlic smelling gas. The reaction area is surrounded by a white crust afterwards. CuSO4 and AgNO3 aqueous solutions become reduced. Impedance measurements yield an ionic conductivity of 2·10−6 S/cm at 25 °C and an activation energy of 0.62 eV. 相似文献
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Structure and visible photoluminescence of Sm3+, Dy3+ and Tm3+ doped c-axis oriented AlN films
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Visible photoluminescence (PL) has been observed from rare earth (Tm, Sm and
Dy)-doped AlN films grown by radio-frequency magnetron reactive sputtering. X-ray
diffraction indicates that the films are c-axis-oriented hexagonal wurtzite type
structure with an average crystal size of about 80--110nm. Room-temperature PL
spectra indicate that the blue emission is due to the transition of 1D2 to
3F4 and 1G2 to 3H6 intra 4f electron of Tm3+, the
yellow emissions of AlN:Sm are due to 4G5/2 to the 6HJ (J =
5/2, 7/2, 9/2, 11/2) and the reddish emissions of AlN:Dy correspond to the
4F9/2 to 6HJ (J = 15/2, 13/2, 11/2 and 9/2) and
6F11/2 transitions. 相似文献
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硫代碱基作为一类免疫抑制性药物被广泛关注,由于硫原子的取代,硫代碱基可以吸收UVA波段紫外光,并通过系间窜越至激发三重态敏化氧气生成广泛应用于光动力学治疗的活性氧物质单态氧(~1O_2).然而,硫代碱基容易与自身敏化产生的~1O_2氧化发生反应,导致光毒性.在已有关于硫代碱基与~1O_2反应机理的研究基础上,本文采用瞬态光谱方法直接测得~1O_2在1270 nm处磷光信号的衰减动力学,得到硫代碱基与单态氧反应的速率常数.通过比较6-硫代鸟嘌呤、4-硫代尿嘧啶、2,4-二硫代尿嘧啶分别在水、乙腈以及二者混合溶剂中与~1O_2的反应,发现硫代碱基与单态氧反应速率常数受溶剂的极性影响.随着溶剂极性增大,反应速率常数则减小.此外,通过对比研究,发现硫代嘧啶类碱基与~1O_2的反应速率小于硫代嘌呤类碱基,说明在光动力学治疗中以硫代嘧啶类药物作为光敏剂是较为合适的选择. 相似文献
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A. Rodríguez B. Morana J. Sangrador T. Rodríguez A. Kling M.I. Ortiz C. Ballesteros 《Superlattices and Microstructures》2009,45(4-5):343-348
SiGeO films were deposited by LPCVD using Si2H6, GeH4 and O2 as reactive gases and furnace annealed to segregate the possible excess of Si and Ge in the form of nanocrystals embedded in an oxide matrix. For low GeH4:Si2H6 flow ratios and deposition temperatures of 450 °C or lower, the deposited film consists of a SiO2 matrix incorporating Ge. No Ge oxides and no nanocrystals are detected. After annealing of the samples with SiO2 matrices at temperatures of 600 °C or higher, quasi-spherical isolated Ge nanocrystals with diameters ranging from 4.5 to 9 nm and homogeneously distributed throughout the whole film thickness are formed. In the samples deposited with low GeH4:Si2H6 flow ratios, the original SiO2 matrix holds its composition. 相似文献
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An atmospheric-pressure plasma jet (APPJ) was directly irradiated at a gas-liquid interface under ambient conditions. The reactive oxygen species (ROS) like hydroxyl radicals (•OH), hydrogen peroxide (H2O2) and ozone (O3) and also reactive nitrogen species (RNS) such as nitrogen oxides (NOx) and nitric acid (HNO3) formed during the plasma discharge were quantified under various experimental parameters. In a chemical dosimetry method, terephthalic acid (TA) was employed for the quantification of •OH and titanium sulfate was used to quantify the H2O2. Quantitative determination of NO3− was carried out by using Ion chromatography (IC). The changes in the solution pH were studied during the plasma treatment. Strong acidification along with the production of dominant reactive nitrogen species and ozone formation were observed with air. The effect of various gases, gas flow rate, various applied voltage and catalyst were studied to optimize the experimental conditions for the best performance. The influence of catalyst Fe2+ salt, TiO2 on the formation of reactive species were studied. The efficiency of the plasma device for the degradation of crystal violet (CV) was also investigated with TiO2 and Fe2+ salt. 相似文献
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用射频/直流磁控溅射法制备了CeO2/Nb2O5双层氧敏薄膜,利用X射线光电子能谱(XPS),描述并解释了单层CeO2薄膜中氧随温度变化的动力学行为,以及CeO2/Nb2O5薄膜界面对氧敏特性的影响.通过对Ce3d XPS谱的高斯拟合,计算了Ce3+浓度并给出了判定Ce4+还原的标志.结果表明,界面效应可以提高CeO2/Nb2O5薄膜中Ce4+的还原能力,使之远远高于单层CeO2薄膜,这对薄膜的氧敏特性是极为有利的.
关键词: 相似文献
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Ricardo Salazar P. A. Navarrete‐Encina J. A. Squella C. Camargo Luis J. Nú?ez‐Vergara 《Journal of Physical Organic Chemistry》2009,22(6):569-577
Reactivity of two new C4‐indolyl substituted 1,4‐dihydropyridines (1,4‐DHPs) toward superoxide anion (O2? ) in dimethylsulfoxide (DMSO) is reported. Reactivity was followed by electrochemical and spectroscopic techniques. Gas chromatography‐mass spectrometry (GC–MS) was used to identify the final products of the reaction. C4 indolyl‐substituted‐1,4‐DHPs reacted toward O2? at significant rates, according to the calculated kinetic rate constants. Results are compared with 4‐phenyl‐DHP and the commercial 1,4‐DHPs, nimodipine, nisoldipine, and amlodipine. Indolyl‐substituted 1,4‐DHPs were more reactive than the commercial derivatives. The direct participation of proton of the 1‐position of the secondary amine in the quenching of O2? was demonstrated. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Abstract As part of an infrared investigation of the kinetics of the reactions of KMnO4 in a KI disk and of KIO4 in a KI disk, the stoichiometry of the two reactions was needed. A previous study1 has shown that MnO4 ? reacts in a KI matrix to produce IO4 ? (which then reacts further to form IO3 ?) and MnO2. Iodate ion is the only observable product in the reaction of IO4 ? in a KI matrix1. The infrared absorption at 740cm?1, which is due to the presence of IO3 ?, was found to obey the Beer-Lambert Law. However, calibration curves for KMnO4 in KI and for KIO4 in KI could not be obtained because both species reacted with the dispersing medium during the preparation of the disk1. It was also observed that no immediate reaction occurred when KBr or KC1 disks containing KMnO4, or KIO4 were prepared. Thus, an extrapolation method was sought which would permit the estimation of calibration curves for the reactive species. 相似文献
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Epitaxial ultrathin NiFe2O4 films were deposited on 1 wt% Nb-doped SrTiO3 (0 0 1) substrates by reactive cosputtering to form junctions with an area of ∼2 mm2, and current-voltage curves show rectifying and asymmetrical hysteresis characteristics. The resistance calculated from the current-voltage curves is strongly voltage dependent, and the hysteretic loops with high and low resistive states were observed. The hysteretic loops are considered to stem from the capacitance effect of the highly resistive NiFe2O4 layer, which leads to charge accumulation at the interfaces. The results show that the interfaces of the junctions have a large areal capacitance of ∼100 nF/mm2 from 300 to 120 K. 相似文献
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G. CHAMBAUD H. GRITLI P. ROSMUS H.-J. WERNER P. J. KNOWLES 《Molecular physics》2013,111(21):1793-1802
The potential energy surfaces (PESs) for several electronic states involved in the reaction O+ (4S) + N2(X1Σ+) → NO+ (X1Σ +, v′) + N(4S) and the role of the ionic N2O+ intermediate have been investigated by ab initio calculations. The 4A″ PES, which correlates with the ground state educts, has a barrier of about 1 eV, and therefore at low collision energies the reaction cannot take place adiabatically on this surface. However, the spin-orbit coupling in the entrance channel allows the system to pass into the Renner-Teller system of the X2 Π electronic ground state of the N2O+ intermediate. The reaction then proceeds on these surfaces up to the region in the exit channel where a similar coupling allows it to reach the product quartet asymptote. At collision energies higher than about 1 eV, the reaction proceeds mainly on the adiabatic PES of the 4A″ state. The A2Σ+ state of N2O+ predissociates via a vibronic coupling with the B2Π state, and in bent structures via a spin-orbit coupling with the 4A″ component of the 4II state. The electronic structure of the B2Π state is found to be of crucial importance for the understanding of the reactive processes in low lying electronic states of N2O+. 相似文献
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Christof Maul Mikhail Poretskiy Jörg Grunenberg 《Journal of Molecular Spectroscopy》2009,256(1):80-85
The possibility of simultaneous characterization of N2O and N2O van der Waals complexes in supersonic jet expansions is demonstrated for neat N2O samples. Room temperature and jet-cooled spectra of the Rydberg transitions 3pπ1Δ ←← X1Σ+ and 3pσ1Π ←← X1Σ+ are presented. Theoretical calculations support the assignment of the Rydberg transitions used. For stagnation pressures above 2 bar, a hitherto unreported broad spectral feature at 84 650 cm−1 is observed, where calculations predict absorption of the (N2O)2 dimer essentially due to excitation of the 4sσ and 3pπ Rydberg orbitals. Consequences for the use of N2O as a precursor for O(1D) atoms in reactive scattering experiments are discussed. 相似文献
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A. Scheibe 《Surface science》2005,577(1):1-14
The kinetics of ammonia oxidation with oxygen have been investigated in the 10−5 and 10−4 mbar range on Pt(5 3 3) and Pt(4 4 3). Only N2 and NO but no N2O were detected as reaction products. The dependence of product formation on temperature and on the partial pressures of the reactants has been studied under steady state conditions. The reactive sticking coefficients were determined under reaction conditions with sreac of ammonia reaching nearly 0.2. The Pt(5 3 3) surface was found to be catalytically more active than Pt(4 4 3) by a factor of 2-4. 相似文献
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The spectroscopic properties in UV-excitable range for the phosphors of Sr3La2(BO3)4:RE3+ (RE3+=Eu3+, Ce3+, Tb3+) were investigated. The phosphors were synthesized by conventional solid-state reactions. The photoluminescence (PL) spectra and commission international de I'Eclairage (CIE) coordinates of Sr3La2(BO3)4:RE3+ were investigated. The f-d transitions of Eu3+, Ce3+ and Tb3+ in the host lattices are assumed and corroborated. The PL and PL excitation (PLE) spectra indicate that the main emission wavelength of Sr3La2(BO3)4:Eu3+ is 611 nm, and Sr3La2(BO3)4:Ce3+ shows dominating emission peak at 425 nm, while Sr3La2(BO3)4:Tb3+ displays green emission at 487, 542, 582 and 620 nm. These phosphors were prepared by simple solid-state reaction at 1000 °C. There are lower reactive temperature and more convenient than commercial phosphors. The Sr3La2(BO3)4:Tb3+ applied to cold cathode fluorescent lamp was found to emit green light and have a major peak wavelength at around 542 nm. These phosphors may provide a new kind of luminescent materials under ultraviolet excitation. 相似文献
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Karthik Nuthalapati Raviraj Vankayala Chi-Shiun Chiang Kuo Chu Hwang 《Particle & Particle Systems Characterization》2020,37(5):2000001
Development of simple, robust, and noninvasive therapeutic approaches to treat cancers and improve survival rates is a grand challenge in clinical biomedicine. In particular, the sizes and shape of the nanomaterials play a vital role in dictating their biodistribution and clearance pathways. It remains elusive how the size and shape of a nanomaterial affect its therapeutic efficacy in cancer diagnosis and treatments. To tackle the above problem, the effects of size and shape of Cu2(OH)PO4 nanostructures (nanosheets and quantum dots) on the photodynamic therapy (PDT) in destroying malignant drug-resistant lung tumors and on combating the tumor hypoxia problem are investigated and compared. The photocatalytic mechanism of Cu2(OH)PO4 nanostructures mainly involves the generation of reactive oxygen species (ROS), such as hydroxyl radical (·OH) and singlet oxygen (1O2). Under an oxygen deprivation condition, Cu2(OH)PO4 nanosheets still can generate OH radicals to kill cancer cells upon near-infrared (NIR) light irradiation. Overall, in vitro and in vivo experiments show that Cu2(OH)PO4 nanosheets can overcome tumor hypoxia problems and effectively mediate dual modal PDT and photothermal therapeutic (PTT) effects on destruction of NCI-H23 lung tumors in mice using ultralow doses (350 mW cm−2) of NIR (915 nm) light. 相似文献
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The time-dependent quantum wave packet (TDWP) and quasiclassical trajectory calculations (QCT) are carried out for the Au(2S) + H2(X1∑+g) → AuH(X1∑+g) + H(2S) reaction on a global potential energy surface. The reaction probabilities at a series of J values, integral cross sections (ICSs) and differential cross sections of the title reaction are calculated by the TDWP method. For reaction probabilities, there are a mass of sharp oscillations at low collision energy, which can be attributed to resonances supported by the potential well. Due to the endothermicity of the title reaction, the total ICS shows a threshold about 1.53 eV. In order to further investigate the reactive mechanism, the lifetime of complex is calculated by QCT method. At the low collision energy, most intermediate complexes are long lived, which implies that the reaction is governed by indirect reactive mechanism. With the collision energy increasing, the direct reactive mechanism occupies the dominant position. Due to the change of the reactive mechanism, the angular distribution shifts toward the forward direction with collision energy increasing. The isotopic variant, Au + D2→AuD + D reaction, is also calculated by TDWP method. The calculated reaction probabilities and ICSs show that the isotope effect reduces the reactivity. 相似文献
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Titanium dioxide (TiO2) thin films were deposited on flexible polycarbonate (PC) substrates by radio frequency (RF) reactive magnetron sputtering. The target was metallic titanium, argon was the plasma gas and oxygen was the reactive gas. Taguchi’s method, which uses an L9 (34) orthogonal array, signal-to-noise ratio and analysis of variance (ANOVA), was employed to study the performance of the deposition process. The effects of the deposition parameters on the structure, morphology and photocatalytic performance of the TiO2 films were analyzed using scanning electron microscopy (SEM), X-ray diffraction, and UV-vis-NIR spectroscopy. Experiments varied RF power (50, 100, 150 W), deposition time (2, 3, 4 h), O2/(Ar + O2) argon/oxygen ratios (40, 60, 80%) and substrate temperatures (room, 80, 120 °C), to optimize the photoinduced decomposition of methylene blue (MB). The experimental results illustrate the effectiveness of this approach. 相似文献
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CdIn2O4 thin films were prepared by direct-current (DC) reactive magnetron sputtering. The structure, surface morphology and the chemical composition of the thin films were analyzed by X-ray diffraction (XRD), atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS), respectively. The electrical properties of the films prepared in different oxygen concentration and annealing treatment were determined, and the effects of the preparing conditions on the structure and electrical properties were also explored. It indicates that the CdIn2O4 thin films with uniform and dense surface morphology contain mainly CdIn2O4, In2O3 phases, and CdO phase is also observed. The XPS analysis confirms the films are in oxygen-deficient state. The electrical properties of these films significantly depend on the preparing conditions, the resistivity of the films with the oxygen concentration of 4.29% is 2.95 × 10−4 Ω cm and the Hall mobility is as high as 60.32 cm2/V s. Annealing treatment can improve the electrical performance of the films. 相似文献