Distribution of Zinc Oxide Nanocrystals in a Polymer Film

The structure of polymer films modified with zinc oxide nanocrystals was studied by the optical absorption and small-angle X-ray scattering methods. Small-angle X-ray scattering allows determination of the nanoparticle size distribution function, which is the decisive factor in predicting the optical properties of heterophase materials, including filled polymer films. The optical absorption spectrum of an acrylate polymer film doped with 1.6 wt % zinc oxide nanocrystals approaches the ideal absorber spectrum, which allows this material to be recommended for use as a protective color filter.     

Deposition of protective-decorative coatings onto aluminum alloys

Technique for deposition of a nickel coating onto various aluminum alloys was developed. This coating can be used both independently and as a sublayer under multilayer coatings and, in particular, under those of nickel, tin–bismuth, lustrous nickel, and lustrous chromium. The technique includes anodization, chemical treatment, and electrodeposition of nickel in a special solution. The working modes of the anodization electrolyte were chosen and the necessity for a preliminary chemical treatment of the oxide film being formed was substantiated. A composition of the acid electrolyte for the subsequent nickel plating was developed with buffer and improving additives. The thus deposited electroplated nickel coatings exhibit a high adhesion to the aluminum base without additional thermal treatment. This makes it possible not only to reduce the technological time for deposition of the subsequent multilayer coatings, but also to fully automate the whole process.     

Physicochemical properties and specific features of crystal formation for complex compounds based on boric acid

New procedure for synthesis of new complex compounds on the basis of boric, aminoacetic, and citric acids was developed. Specific features of the crystal formation for boron-based complex compounds were studied. The supposed application area of these compounds is associated with their biocide activity toward pathogenic microorganisms, such as Eschericia coli (intestinal bacterium), Staphylococcus aureus (aurococcus), and Candida albicans (yeast-like fungi of Candida genus).     

Chemical transformations of tetracyclo[3.3.1.1<Superscript>3,7</Superscript>.0<Superscript>1,3</Superscript>]decane (1,3-dehydroadamantane): II. Reaction of 1,3-dehydroadamantane with <Emphasis Type="Italic">N,N</Emphasis>-dialkylcarboxamides

Alkylation of N,N-dialkylcarboxamides with 1,3-dehydroadamantane has been accomplished for the first time. The reaction involves the C–H bond in the α-position with respect to the carbonyl group and provides a convenient one-step preparation of substituted carboxylic acid amides containing an 1-adamantyl substituent and a pharmacophoric group in the amide moiety.     

Synthesis of 2-(5-aryl-4-methyl-2-oxo-1,2-dihydro- 3<Emphasis Type="Italic">H</Emphasis>-pyrrol-3-ylidene)malononitriles

4-Oxoalkane-1,1,2,2-tetracarbonitriles in the presence of an equimolar amount of morpholine were converted to previously unknown 2-(5-aryl-4-methyl-2-oxo-1,2-dihydro-3H-pyrrol-3-ylidene)malononitriles.     

Study of the mechanism of formation of heterocyclic disulfonium dications from 1,3-benzothiazole-2-thiol and 1-iodopropan-2-one

The potential energy surface for the formation of heterocyclic disulfonium dications from 1,3-benzothiazole-2-thiol and 1-iodopropan-2-one has been analyzed at the DFT B3LYP level of theory. The reaction involves oxidation of 1,3-benzothiazole-2-thiol to the corresponding disulfide, followed by alkylation of the exocyclic sulfur atoms. Stabilization of the salt with iodide anion is initiated by thermodynamically controlled reaction with molecular iodine, leading to the formation of stable structure with triiodide anion.     

New chalcones containing carbazole and 3,4-ethylenedioxythiophene fragments

Russian Journal of Organic Chemistry - Acylation of 9-(2-ethylhexyl)carbazole with acetyl bromide in the presence of tin(IV) chloride gave 3-acetyl- and 3,6-diacetyl-9-(2-ethylhexyl)carbazoles...     

Halocyclization of 2-allyl(propargyl)sulfanyl-6-aminopyrimidin-4(3H)-ones

Russian Journal of Organic Chemistry - The alkylation of 6-amino-2-thiouracil with allyl, methallyl, and propargyl halides in the presence of bases gave 2-[allyl(methallyl,...     

Application of thermal analysis for evaluating the digestion of microwave pre-treated sewage sludge

The effect of microwave pre-treatment (MwP) on anaerobic digestion of sewage sludge was studied by means of thermal analysis and evolved gas analysis. The effect of the pre-treatment at low energy input (<1000 kJ L^?1) on sludge solubilisation was studied with the aid of response surface methodology. The pre-treatment process was subsequently studied at energies of 488–2700 kJ L^?1 to evaluate the improvement in biogas production under mesophilic conditions. Organic matter modifications were studied using a Setaram TGA92 analyser at atmospheric pressure coupled to an MSC200 quadrupole mass spectrometer from Balzers. Particle size analysis was carried out using a Laser Diffraction Particle Size Analyser LS 13 320 Beckmann Coulter for evaluating the effect of MwP on sludge particles. Results showed an increase in organic matter solubilisation with the increase in the energy applied. Modifications in the specific surface area of the organic matter due to the MwP resulted in increments in methane yields. However, an accumulation of complex compounds was observed in thermal profiles at the maximum energy input (2700 kJ L^?1). Semi-continuous digestion experiments were evaluated using as substrate pre-treated sludge at the optimum energy value (975 kJ L^?1). Results showed a significant increase in methane yield (43 %) when evaluating the process at hydraulic retention times (HRTs) of 25–10 days.     

An improved solvent-free synthesis of flunixin and 2-(arylamino) nicotinic acid derivatives using boric acid as catalyst

A simple solvent-free protocol for the preparation of flunixin, a potent non-narcotic, non-steroidal anti-inflammatory drugs is reported using boric acid as catalyst. Its salt, flunixin meglumine are then prepared under reflux in EtOH. This sustainable method are then extended for the synthesis of a series of 2-(arylamino) nicotinic acid derivatives. The present protocol combines non-hazardous neat conditions with associated benefits like excellent yield, straightforward workup, and use of readily available and safe catalyst in the absence of any solvent, which are important factors in the pharmaceutical industry. The pathway for catalytic activation of 2-chloronicotic acid with boric acid was also investigated using Gaussian 03 program package.

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