Silica - Titania Support for HVOC's Combustion Catalysts

Preparation of support series for catalysts of combustion of halogenated volatile organic compounds (H-VOC's) was carried out. It was stated that all they allow preparing active catalysts however their main drawback is the lack of hardness against products of H-VOC's combustion e.g. hydrogen chloride and chlorine. Laboratory tests showed that titania and silica - titania supports were characterized by the highest hardness against chlorine derivatives. In comparison to the titania supports, low content (ca. 10 wt.%) silica-containing supports have better mechanical properties, i.e. mechanical strength and attrition resistance. In this paper the method of preparation, composition and physicochemical properties of silica - titania support are presented. This revised version was published online in June 2006 with corrections to the Cover Date.     

Interaction of oxygen-sensitive luminescent probes Ru(phen)(3)(2+) and Ru(bipy)(3)(2+) with animal and plant cells in vitro. Mechanism of phototoxicity and conditions for non-invasive oxygen measurements.

Understanding the role of oxygen in the physiology, pathophysiology and radio- and chemosensitivity of animal cells requires accurate and non-invasive measurements of oxygen concentrations in the range of 0-2x10(-4) M, in cells in vitro or in vivo. High resolution 3D imaging techniques could be particularly useful in investigating tissue oxygenation in vivo and in model tissues (multicellular spheroids) in vitro. The goals of this work were to develop microscopy techniques and (i) to define conditions under which two oxygen-sensitive luminescent dyes, Ru(bipy)(3)(2+) (tris(2,2'-bipyridyl)ruthenium(II) chloride hexahydrate) and Ru(phen)(3)(2+) (tris(1,10-phenanthroline)ruthenium(II) chloride hydrate) can be used to probe oxygen concentrations within viable cells in vitro, when no phototoxic effects are evident, and (ii) to investigate the mechanism of phototoxicity once cell damage occurs. This report demonstrates that Ru(bipy)(3)(2+) and Ru(phen)(3)(2+) do not pass through intact biological membranes, do not cause measurable photodamage to plasma membranes at a concentration of 0.2 mM and, when loaded into endosomes, yield a strong luminescent signal. However, at an extracellular concentration of 1 mM, in the presence of 457-nm light, detectable amounts of both complexes accumulate at the plasma membrane and cause a loss of membrane integrity via a mechanism which may involve the generation of singlet oxygen.     

Three‐Dimensional Information on the Phase Domain Structure of Thin Films of Polymer Blends Revealed by Secondary Ion Mass Spectrometry

We describe the technique of dynamic secondary ion mass spectrometry developed to determine three‐dimensional phase domain structures of films of polymer blends. The polymers are composed of light elements or are labeled with deuterium or heavy elements. The applicability of this method to various polymer blends forming thin and ultrathin films with flat and undulated air/film interface is discussed.     

Photochemical ring opening of barbital

Photolysis of barbital yields derivatives of urea and biuret. The mechanism of ring opening involves an isocyanate intermediate.     

Differential density matrix overlap: an index for assessment of electron correlation in atoms and molecules

Summary A new index, called the differential density matrix overlap (DDMO), is proposed for assessment of the electron correlation effects in atoms and molecules. DDMO can be easily calculated as the negative value of the correlation energy derivative with respect to the relative position of the occupied and virtual orbitals. DDMO is transparent to physical interpretation. It can serve as a tool for analyzing the accuracy of approximate electron correlation methods and the validity of the Hartree-Fock wavefunction as the zeroth-order approximation. The properties of DDMO are discussed using test calculations on 11 atoms and molecules as an example.     

Ortho effect in the mass spectrometric behaviour of N(pyrimidin-4-yl)aminobenzoic acids and their methyl esters

Ortho-. meta- and para-isomers of N-(pyrimidin-4-yl)aminobenzoic acid and their methyl esters were investigated by electron impact mass Spectrometry. Their fragmentation was found to be strongly dependent on the position of the substituent in the aminobenzoic moiety. Two different kinds of ortho effect were studied and confirmed with the aid of deuterium-labelled derivatives.     

The synthesis of the africane-type sesquiterpenoid, 1,5,8,8-tetramethyl-tricyclo[8,1,0,02,6]undec-5-en-9-ol-4-one

One of the alcohols derived from rearrangement of humulene-4,5-epoxide has been converted into a keto-alcohol, the angelate ester of which is a naturally-occurring sesquiterpenoid.     

A nontrivial vacuum state in D = 10, N = 1 supergravity

We find a ground state of D = 10, N = 1 supergravity of the form (AdS(3) × R¹) × S³ × T³ which preserves all supersymmetries and should provide a gauged D = 4, N = 4 supergravity coupled to supermatter after dimensional reduction.