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991.
With a linear relativistic method we calculated the band structure of gold. A comparison with the results of a RAPW calculation shows that the deviation is about 3%. The effort of computational time is for the linear method considerably smaller than for the RAPW method. 相似文献
992.
A general method of determination of the mean square amplitudes of lattice oscillations (MSA) for crystals with sphalerite structure is described and applied to InP. The linearity of suitable functions of the measured integral BRAGG intensities of sin2 θ/λ2 is used for the verification of the parameters selected for the correction of extinction and DTS. In this way the accuracy of the results is increased. The MSAs of the InP-sublattices are evaluated. According to theoretical expectations the MSAs of the P-sublattice are larger because of the greater contributions of optical phonons. 相似文献
993.
L. M. Khalilov E. A. Paramonov A. Z. Khalilova V. N. Odinokov A. A. Muldashev U. A. Baltaev U. M. Dzhemilev 《Chemistry of Natural Compounds》2001,37(4):339-342
The components of fragrance from four wormwood species of theArtemisiaL. genus were analyzed by GC-MS. The major and minor components of volatile essential oils typical of the studied plant species were determined. 相似文献
994.
995.
With the binucleating ligand 1-oxy-2,6-di [(N,N-biscarboxymethyl)aminomethyl]- 4-chlorobenzol (H5L) complexes of formulae FeH2L · 2H2O; FeH3L(C1O4) · H2O; Fe2L(OH) · 2H2O; M2HL · nH2O (M = Co, Cu, n = 2; M = Ni, n = 4); FeCuL · 3H2O; FeCrL(OH) · 3H2O were prepared and characterized by elemental analysis, IR and electronic spectra and magnetic moment determinations. In addition, thermal analysis data of the complexes and Mössbauer effect spectra of the iron containing complexes are also given and discussed. 相似文献
996.
N-Benzyl-2-naphthohydroxamic acid extracts vanadium(V) selectively and quantitatively into chloroform from 2-8.5M hydrochloric acid in the presence of Mo(VI), Zr(IV) and Ce(IV). The extraction takes place quickly and gives a stable reddish-violet extract which shows an absorption maximum at 505 nm with molar absorptivity of (5.34 +/- 0.05) x 10(3) 1.mole(-1).cm(-1). The optimum range for the determination is 2.2-7.4 ppm of vanadium(V) in the final solution. The method has been used for the determination of vanadium in steels. 相似文献
997.
A. Müller W. Plass E. Krickemeyer S. Dillinger H. Bögge A. Armatage C. Beugholt U. Bergmann 《Monatshefte für Chemie / Chemical Monthly》1994,125(5):525-533
Summary The X-ray crystal structure of the compound Na3(NH4)12[Mo57Fe6(NO)6O174(OH)3(H2O)24]·76H2O (3) [P63/mmc;a=2380.6(5),c=2763.4(7),Z=2], the giant cluster anion of which has the shape of a doughnut, shows remarkable details: The cluster [{Fe(H2O)2}6{Mo(-H2O)2(-OH)Mo}3{ Mo15(MoNO)
2
3+
O58(H2O)2}3]15– can be described as being composed of three transferable {Mo17} ligands bridged by cationic centers and contains a novel nanodimensional central cavity. 相似文献
998.
Characterization of porosity in vapor-deposited amorphous solid water from methane adsorption 总被引:2,自引:0,他引:2
We have characterized the porosity of vapor-deposited amorphous solid water (ice) films deposited at 30-40 K using several complementary techniques such as quartz crystal microgravimetry, UV-visible interferometry, and infrared reflectance spectrometry in tandem with methane adsorption. The results, inferred from the gas adsorption isotherms, reveal the existence of microporosity in all vapor-deposited films condensed from both diffuse and collimated water vapor sources. Films deposited from a diffuse source show a step in the isotherms and much less adsorption at low pressures than films deposited from a collimated source with the difference increasing with film thickness. Ice films deposited from a collimated vapor source at 77 degrees incidence are mesoporous, in addition to having micropores. Remarkably, mesoporosity is retained upon warming to temperatures as high as 140 K where the ice crystallized. The binding energy distribution for methane adsorption in the micropores of ice films deposited from a collimated source peaks at approximately 0.083 eV for deposition at normal incidence and at approximately 0.077 eV for deposition at >45 degrees incidence. For microporous ice, the intensity of the infrared bands due to methane molecules on dangling OH bonds on pore surfaces increases linearly with methane uptake, up to saturation adsorption. This shows that the multilayer condensation of methane does not occur inside the micropores. Rather, filling of the core volume results from coating the pore walls with the first layer of methane, indicating pore widths below a few molecular diameters. For ice deposited at 77 degrees incidence, the increase in intensity of the dangling bond absorptions modified by methane adsorption departs from linearity at large uptakes. 相似文献
999.
U. Pandey A. Mukherjee G. Samuel S. Banerjee H. D. Sarma M. Venkatesh 《Journal of Radioanalytical and Nuclear Chemistry》2008,275(2):243-246
Lanreotide, a somatostatin analogue, was radioiodinated with 125I to explore the possibility of using 123I labeled lanreotide as a diagnostic radiopharmaceutical for tumors overexpressing somatostatin (SST) receptors. Radioiodination
was carried out with 125I using chloramine T as the oxidant. The labeling yield was >90%. Characterization of 125I-Lanreotide was carried out by paper electrophoresis as well as HPLC. 125I-Lanreotide was purified by chromatography using a C18 Sep-Pak column. Radiochemical purity of the purified 125I-Lanreotide thus obtained was >99%. Significant tumor uptake of 125I-Lanreotide was observed in C57BL/6 mice bearing melanoma. 相似文献
1000.
A. Srivastava K. K. Swain B. Vashisht P. Aggarwal U. Mete R. Acharya D. N. Wagh A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):191-194
Four kidney stones collected from patients being treated in the Advance Urology Centre of PGIMR, Chandigarh were characterized using instrumental neutron activation analysis (INAA), energy dispersive X-ray fluorescence (EDXRF) and X-ray diffraction (XRD) techniques. For INAA, samples were irradiated in tray rod facility of Dhruva reactor, Mumbai and pneumatic fast transfer system of KAMINI reactor, IGCAR, Kalpakkam. Radioactive assay was carried out using HPGe detector coupled to 8k channel analyzer. Elements determined in the samples by INAA are Zn, Sr, Co, Fe, Cr, Sc, Se, Na and Mn. EDXRF was used for the quantification of Ca. XRD patterns showed that three of the kidney stones are calcium oxalate stone and the other one is uric acid stone. The concentrations of trace elements in general were found to be higher in calcium oxalate stones and positive correlation was observed in the concentrations of Ca with Sr and Zn. 相似文献