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Mayboroda I. O. Kolobkova E. M. Grishchenko Yu. V. Chernykh I. A. Zanaveskin M. L. Chumakov N. K. 《Crystallography Reports》2021,66(3):520-524
Crystallography Reports - The formation of β-Si3N4 for subsequent growth of AlGaN and GaN heterostructures of silicon wafers has been studied. It is established that the native oxide layer... 相似文献
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Ezubchenko I. S. Chernykh M. Ya. Mayboroda I. O. Trun’kin I. N. Chernykh I. A. Zanaveskin M. L. 《Crystallography Reports》2020,65(1):122-125
Crystallography Reports - The effect of trimethylaluminum preflow time on the crystalline quality of AlN films grown by metalorganic chemical vapor deposition on Si(111) substrates has been... 相似文献
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In 1977 the celebrated theorem of B. Dahlberg established that the harmonic measure is absolutely continuous with respect to the Hausdorff measure on a Lipschitz graph of dimension in , and later this result has been extended to more general non-tangentially accessible domains and beyond.In the present paper we prove the first analogue of Dahlberg's theorem in higher co-dimension, on a Lipschitz graph Γ of dimension d in , , with a small Lipschitz constant. We construct a linear degenerate elliptic operator L such that the corresponding harmonic measure is absolutely continuous with respect to the Hausdorff measure on Γ. More generally, we provide sufficient conditions on the matrix of coefficients of L which guarantee the mutual absolute continuity of and the Hausdorff measure. 相似文献
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The present paper establishes boundedness of $[m-\frac{n}{2}+\frac{1}{2} ]$ derivatives for the solutions to the polyharmonic equation of order 2m in arbitrary bounded open sets of ${\mathbb{R}}^{n}$ , 2≤n≤2m+1, without any restrictions on the geometry of the underlying domain. It is shown that this result is sharp and cannot be improved in general domains. Moreover, it is accompanied by sharp estimates on the polyharmonic Green function. 相似文献
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Ramautar R Mayboroda OA Derks RJ van Nieuwkoop C van Dissel JT Somsen GW Deelder AM de Jong GJ 《Electrophoresis》2008,29(12):2714-2722
A capillary electrophoresis-time of flight-mass spectrometry (CE-TOF-MS) method for the analysis of amino acids in human urine was developed. Capillaries noncovalently coated with a bilayer of Polybrene (PB) and poly(vinyl sulfonate) (PVS) provided a considerable EOF at low pH, thus facilitating the fast separation of amino acids using a BGE of 1 M formic acid (pH 1.8). The PB-PVS coating proved to be very consistent yielding stable CE-MS patterns of amino acids in urine with favorable migration time repeatability (RSDs <2%). The relatively low sample loading capacity of CE was circumvented by an in-capillary preconcentration step based on pH-mediated stacking allowing 100-nL sample injection (i.e. ca. 4% of capillary volume). As a result, LODs for amino acids were down to 20 nM while achieving satisfactory separation efficiencies. Preliminary validation of the method with urine samples showed good linear responses for the amino acids (R(2) >0.99), and RSDs for peak areas were <10%. Special attention was paid to the influence of matrix effects on the quantification of amino acids. The magnitude of ion suppression by the matrix was similar for different urine samples. The CE-TOF-MS method was used for the analysis of urine samples of patients with urinary tract infection (UTI). Concentrations of a subset of amino acids were determined and compared with concentrations in urine of healthy controls. Furthermore, partial least squares-discriminant analysis (PLS-DA) of the CE-TOF-MS dataset in the 50-450 m/z region showed a distinctive grouping of the UTI samples and the control samples. Examination of score and loadings plot revealed a number of compounds, including phenylalanine, to be responsible for grouping of the samples. Thus, the CE-TOF-MS method shows good potential for the screening of body fluids based on the analysis of endogenous low-molecular weight metabolites such as amino acids and related compounds. 相似文献
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E. I. Mayboroda Yu. L. Slominsky A. V. Turov A. I. Tolmachev 《Chemistry of Heterocyclic Compounds》2008,44(1):78-85
Tetramethylene-2,2′-bis(1,3,3-trimethyl-(3H)-indolium),-3-ethylbenzothiazolium,-1-methyl-quinolinium, and-1-methyl-and-1-butylbenz[c,d]indolium
salts were synthesized starting from them trimethinecyanines containing an ethylene bridging group in the α, α′-positions
of the chromophore have been prepared. These compounds are converted to their analogs containing a vinylene group by the action
of benzoquinones. In the case of thiacarbocyanines the effect of the indicated bridging groups on the conformation and protonation
route of the carbocyanines has been studied. The chromaticity of the dyes has been investigated.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 94–102, January, 2008. 相似文献
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Consider a second order divergence form elliptic operator L with complex bounded measurable coefficients. In general, operators based on L, such as the Riesz transform or square function, may lie beyond the scope of the Calderón–Zygmund theory. They need not be
bounded in the classical Hardy, BMO and even some L
p
spaces. In this work we develop a theory of Hardy and BMO spaces associated to L, which includes, in particular, a molecular decomposition, maximal and square function characterizations, duality of Hardy
and BMO spaces, and a John–Nirenberg inequality.
S. Hofmann was supported by the National Science Foundation. 相似文献
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