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91.
Wiktor Oktaba 《Applications of Mathematics》1998,43(2):119-131
The aim of this paper is to characterize the Multivariate Gauss-Markoff model (MGM) as in (2.1) with singular covariance matrix and missing values. MGMDP2 model and completed MGMDP2Q model are obtained by three transformations D, P and Q (cf. (3.21)) of MGM. The unified theory of estimation (Rao, 1973) which is of interest with respect to MGM has been used.The characterization is reached by estimation of parameters: scalar 2 and linear combination
as in (4.8), (4.6), (4.7) as well as by the model of the form (5.1) (cf. Th. 5.1). Moreover, testing linear hypothesis in the available model MGMDP2 by test function F as in (6.3) and (6.4) is considered.It is known (Oktaba 1992) that ten quantities in models MGMDP2, and MGMDP2Q are identical (invariant). They permit to say that formulas for estimation and testing in both models are identical (Oktaba et al., 1988, Baksalary and Kala, 1981, Drygas, 1983).An algorithm and the UMGMBO program for calculations concerning estimation and testing in MGM have been presented by Oktaba and Osypiuk (1993). 相似文献
92.
P. Gluziński J. W. Krajewski St. Kasprzyk J. Bleidelis A. Mishnyov A. Kemme 《Journal of chemical crystallography》1987,17(4):495-504
trans-1,4,10,13-Tetraoxa-7,16-diazacyclooctadecano-7-acetatocopper(II) chloride has been investigated by X-ray diffraction methods. The compound crystallises in the orthorhombic system, space groupPbca (No. 61), with cell dimensionsa=12.734(2),b=11.965(2),c=23.252(3) Å, andZ=8. The structure was solved by the heavy-atom method, and refined by full-matrix least squares to giveR=0.049 for 2749 observed reflections. The 18-membered heteroring, when considered without the acetate group, has approximateC
2 symmetry. The copper atom in the cavity of the macrocycle has an irregular octahedral coordination sphere, with two elongated coordination distances. 相似文献
93.
K. Samochocka G. Mroczkowska M. Czauderna J. Szymendera M. Kasprzyk 《Journal of Radioanalytical and Nuclear Chemistry》1986,106(3):159-166
The reaction of platinum-methionines and platinum-selenomethionine complexes with ytterbium chloride was studied. The biodistribution of these organic platinum complexes labelled with169Yb was examined in animals bearing Ehrlich tumor. It was found that the retention of radioactivity from labelled monomethionin- and monoselenomethioninplatinum complexes in animals after 72 h was about 60% while the retention from dimethioninplatinum complex was about 6%. 相似文献
94.
95.
96.
St. J. v. Przylecki und K. Kasprzyk 《Fresenius' Journal of Analytical Chemistry》1938,115(5-6):216-217
Ohne Zusammenfassung 相似文献
97.
Mateusz Galica Wiktor Kasprzyk Szczepan Bednarz Dariusz Bogdał 《Chemical Papers》2013,67(9):1240-1244
This work deals with catalytic activity of tetrabutylammonium decatungstate(VI) in the oxidation of selected alcohols with hydrogen peroxide as an oxidant using 1,2-dichloroethane/water or acetonitrile/water as a solvent system. Different forms of heating were compared. The highest conversions of substrates were achieved in the two phase system acetonitrile/water using microwave irradiation combined with elevated pressure. Finally, optimum parameters for these reactions in a microwave pressurised reactor were established and discussed. 相似文献
98.
The influence of the substrate structure and concentration on the yield of the Passerini reaction was studied. A new, solvent‐free methodology for a convenient preparation of α‐acyloxyamides 4 was established and compared to the classical methodology. A higher reaction yield was obtained in shorter time, especially in the case of aromatic aldehydes. 相似文献
99.
The possibility of the application of non-covalently functionalized graphene as a sensing membrane for the potentiometric determination of zinc ions was examined. A graphene carboxylic derivative was functionalized with 1-(2-pyridylazo)-2-naphthol, the Zn(2+) ions complexing ligand, simply by adsorption of ligand molecules due to π-π interactions. This approach has resulted in a potentiometric sensor characterized with significant selectivity for Zn(2+) ions present in solution. 相似文献
100.
Dr. Suresh Babu Kalidindi Hyunchul Oh Dr. Michael Hirscher Dr. Daniel Esken Christian Wiktor Dr. Stuart Turner Prof. Dr. Gustaaf Van Tendeloo Prof. Dr. Roland A. Fischer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(35):10848-10856
Three‐dimensional covalent organic frameworks (COFs) have been demonstrated as a new class of templates for nanoparticles. Photodecomposition of the [Pd(η3‐C3H5)(η5‐C5H5)]@COF‐102 inclusion compound (synthesized by a gas‐phase infiltration method) led to the formation of the Pd@COF‐102 hybrid material. Advanced electron microscopy techniques (including high‐angle annular dark‐field scanning transmission electron microscopy and electron tomography) along with other conventional characterization techniques unambiguously showed that highly monodisperse Pd nanoparticles ((2.4±0.5) nm) were evenly distributed inside the COF‐102 framework. The Pd@COF‐102 hybrid material is a rare example of a metal‐nanoparticle‐loaded porous crystalline material with a very narrow size distribution without any larger agglomerates even at high loadings (30 wt %). Two samples with moderate Pd content (3.5 and 9.5 wt %) were used to study the hydrogen storage properties of the metal‐decorated COF surface. The uptakes at room temperature from these samples were higher than those of similar systems such as Pd@metal–organic frameworks (MOFs). The studies show that the H2 capacities were enhanced by a factor of 2–3 through Pd impregnation on COF‐102 at room temperature and 20 bar. This remarkable enhancement is not just due to Pd hydride formation and can be mainly ascribed to hydrogenation of residual organic compounds, such as bicyclopentadiene. The significantly higher reversible hydrogen storage capacity that comes from decomposed products of the employed organometallic Pd precursor suggests that this discovery may be relevant to the discussion of the spillover phenomenon in metal/MOFs and related systems. 相似文献