Results are given for a study of the TiL, TiL, and NK x-ray emission bands in TiC1–xNx compounds (x from 0.038 to 0.930). These spectra served as the basis for a discussion of the structure of the energy bands of TiC–TiN solid solutions and the evaluation of the validity of various theoretical models. The possibility of determining the composition of solid carbonitride alloys by analysis of the intensity of the x-ray emission bands was examined.Institute of Metal Physics, Urals Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 6, pp. 75–78, November–December, 1989. 相似文献
Present work describes investigations of a two-step process consisting of galvanostatic anodising in a 1 M H2SO4 solution at 100 mA cm−2 up to the limiting voltages of 20, 60, 80, 100 and 120 V, directly after which potentiostatic regime was employed and the current was allowed to drop. The total treatment time (5 min) was held constant for all samples. The treatment was carried out to improve the corrosion resistance of zirconium in physiological conditions, which was determined by electrochemical evaluation in Ringer’s solution. XPS studies revealed that after anodising sulphur was incorporated into the oxide film in the form of sulphated zirconia. The maximum content of sulphate in the oxide layer was observed after anodising at 80 V. Anodising at higher voltages resulted in formation of coatings with decreasing amount of sulphur. It was found that there is a strong correlation between the sulphur content in the oxide layers and the measured corrosion current density. On the other hand, the pitting corrosion resistance seemed to be unaffected by the presence of S and it was improving with the increasing limiting voltage of the treatment.
Russian Physics Journal - Studies of K-shell plasma radiation sources were performed on the GIT-12 generator (4.7 MA, 1.7 μs). In the experiments, a new type of load configuration was used to... 相似文献
The catalytic activity of the systems based on titanium(iv) alkoxides (Ti(OPri)4, Ti(OPri)2(OCH(CF3)2)2, and Ti(OCH(CF3)2)4) and mixtures of alkylaluminum chlorides (Et2AlCl or Et3Al2Cl3) with dibutylmagnesium in ethylene polymerization and ethylene copolymerization with propylene and 5-ethylidene-2-norbornene was studied. Ultrahigh-molecular-weight polyethylene with the molecular weight reaching 4.9 · 106 Da was found to be formed in the homopolymerization reaction, whereas copolymerization gives ter-copolymers containing propylene (up to 35 mol.%) and 5-ethylidene-2-norbornene (4.3 mol.%) units.
Non-resonant V L2,3 and OKα X-ray emission spectra of a new series of (Cu,V)Sr2Can−1CunOy (n=3-7) superconductors are presented. We have found that oxygen atoms surround V-atoms in the given compounds, form a (VO4)3− tetrahedrons and have a pentavalent state. This induces holes due to the substitution of divalent copper by pentavalent vanadium ions providing a hole-doping mechanism of superconductivity in this series of compounds. A spectral estimation of the oxygen concentration shows that the oxygen content under high-pressure/high-temperature synthesis conditions is not changed considerably from the start to the final product. 相似文献
JETP Letters - The results of full study of X-ray photoelectron spectra (XPS) of spin-liquid candidate CuAl2O4 including the measurements of high-energy resolved core level (Cu $$2p$$ , Al $$3p$$ ,... 相似文献
A numerical simulation was done to check the possibility of using planar C/C/C multilayers with density contrast 0.2 and 0.7 g/cm3 as an X-ray waveguide. After an optimization procedure, suitable waveguide layer thicknesses were found which provide a high degree of resonant standing wave field intensity enhancement in the core layer at incident beam energy of 13 keV. The obtained results were compared with those of the Mo/Be/Mo waveguide, whose high waveguiding capability at the same energy value was reported in the 1990s. The comparison shows that standing wave field intensity resonant enhancement provided by C/C/C planar multilayers is very high and, consequently, a guided beam can be well detected. 相似文献
2,3 X-ray emission spectra of porous silicon (P-Si) and of spark-processed silicon (sp-Si). Both types of Si-structure display strong photoluminescence in the visible range of the spectrum. Porous
samples were prepared by anodization of n-- and p+-Si-wafers. Whereas for the P-Si processed from p+-Si the presence of some amorphous silicon is detected, the X-ray emission spectra of porous Si prepared from n--Si display a higher content of SiO2. For spark-processed Si the Si L2,3 X-ray emission spectra reveal a much stronger degree of oxidation which extends to depths larger than 10000 Å. Furthermore,
the chemical state of silicon atoms of sp-Si measured at the center of the processed area is close to that of silicon dioxide,
and it has an influence on the photoluminescence energy. Specifically, green photoluminescent sp-Si shows a higher degree
of oxidation than the blue luminescent specimen. However, the depth of oxidation consistently decreases in areas with weak
or no PL. Possible origins of the observed photoluminescence are discussed.
Accepted: 6 March 1997 相似文献
