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1.
Structural Chemistry - The crystal and molecular structure of tris(tetrabutylammonium) pentanitratoplumbate(II) was determined and characterized by single-crystal and powder X-ray diffraction and...  相似文献   
2.
Russian Journal of Applied Chemistry - Organo-inorganic composite materials based on films of polytetrafluoroethylene and tetrafluoroethylene–hexafluoropropylene copolymer, modified with...  相似文献   
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Journal of Radioanalytical and Nuclear Chemistry - In the present paper the development and application of a novel somatostatin radioimmunoassay are described. 125I-labeling of...  相似文献   
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The restrictions Bspq() and Fspq() of the Besov and Triebel–Lizorkinspaces of tempered distributions Bspq(Rn) and Fspq(Rn) to Lipschitzdomains Rn are studied. For general values of parameters (sR,p>0, q>0) a ‘universal’ linear bounded extensionoperator from Bspq() and Fspq() into the corresponding spaceson Rn is constructed. The construction is based on a new variantof the Calderón reproducing formula with kernels supportedin a fixed cone. Explicit characterizations of the elementsof Bspq() and Fspq() in terms of their values in are also obtained.  相似文献   
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Crystals of maleates of three amino acids with hydrophobic side chains [L‐leucenium hydrogen maleate, C6H14NO2+·C4H3O4, (I), L‐isoleucenium hydrogen maleate hemihydrate, C6H14NO2+·C4H3O4·0.5H2O, (II), and L‐norvalinium hydrogen maleate–L‐norvaline (1/1), C5H11NO2+·C4H3O4·C5H12NO2, (III)], were obtained. The new structures contain C22(12) chains, or variants thereof, that are a common feature in the crystal structures of amino acid maleates. The L‐leucenium salt is remarkable due to a large number of symmetrically non‐equivalent units (Z′ = 3). The L‐isoleucenium salt is a hydrate despite the fact that L‐isoleucine is a nonpolar hydrophobic amino acid (previously known amino acid maleates formed hydrates only with lysine and histidine, which are polar and hydrophilic). The L‐norvalinium salt provides the first example where the dimeric cation L‐Nva...L‐NvaH+ was observed. All three compounds have layered noncentrosymmetric structures. Preliminary tests have shown the presence of the second harmonic generation (SGH) effect for all three compounds.  相似文献   
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The process of uranium precipitation from nitrate-sulfuric acid eluates by a 25% aqueous solution of ammonia was investigated. The effect of precipitation pH value on the impurity composition, particle size and bulk density of the yellow cake was studied. It was found, that precipitation should be carried out at pH 6.7 to obtain a high-purity concentrate. The method makes it possible to obtain a concentrate with an uranium content of 71.79%, a high bulk density of 970 kg m?3, an average particle diameter of 10.3 μm. The impurity composition of concentrate obtained at pH 6.7 meets the requirements of ASTM C967-13.  相似文献   
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Characterizations via convolutions with smooth compactly supported kernels and other distinguished properties of the weighted Besov–Lipschitz and Triebel–Lizorkin spaces on ℝn with weights that are locally in Ap but may grow or decrease exponentially at infinity are investigated. Square–function characterizations of the weighted Lp and Hardy spaces with the above class of weights are also obtained. A certain local variant of the Calderón reproducing formula is constructed and widely used in the proofs.  相似文献   
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