A novel stereospecific synthesis of muscalure,the sex pheromone of house fly (musca domestica)

Partial ozonolysis of 1Z,5Z-cyclooctadiene followed by selective transformation of ester and acetal groups in methyl ester of 8,8-dimethoxy-4Z-octen-1-oic acid, and by a two step elongation of carbon chain of the latter by means of tosyloxy groups teplacement under action of decyl- and pentyl magnesium bromides leads to musculare - the sex pheromone of house fly.     

Li,Cs||F,NO<Subscript>3</Subscript> ternary reciprocal system

The Li, Cs||F, NO₃ ternary reciprocal system was for the first time described and experimentally studied by differential thermal analysis and differential scanning calorimetry. Phase equilibrium states were determined, and so were the compositions and melting points of two ternary eutectics. Reactions describing the chemical interaction in the system were presented.     

Electronic properties of A<Subscript>2</Subscript>B<Subscript>6</Subscript> quantum dots incorporated into Langmuir–Blodgett films

An experimental and theoretical study is performed for features of the electronic spectrum of CdSe/CdS/ZnS quantum dots incorporated into Langmuir–Blodgett films. Analysis of the investigated samples assesses the state of the first three levels of the electron spectrum for a quantum object. Good qualitative and quantitative agreement is achieved between the experimental results and theoretical estimates. It is shown that the mechanism of the observed field emission current through a quantum dot is described satisfactorily by the Morgulis–Stratton theory under the considered experimental conditions.     

Phase transitions and dielectric relaxation in (1 − <Emphasis Type="Italic">x</Emphasis>)SrTiO<Subscript>3</Subscript>-<Emphasis Type="Italic">x</Emphasis>BiFeO<Subscript>3</Subscript> (0 ≤ <Emphasis Type="Italic">x</Emphasis> ≤ 0.04)

The dielectric and acoustic properties of (1 − x)SrTiO₃-xBiFeO₃ (0 ≤ x ≤ 0.04) solid solutions have been studied in the temperature range 10–300 K. The polar state exhibiting permittivity dispersion and dielectric hysteresis loops has been revealed at temperatures of 40–100 K. At 20–40 K, we have observed one more dielectric relaxation, which is not associated with the polar state and vanishes at a concentration of the second solid-solution component x = 0.04. The antiferrodistorsive transition has been found to vary with increasing concentration x. At temperatures below the antiferrodistorsive transition point, the polar (relaxor) state has been shown to persist in all the measured solid solutions.     

Adsorption interactions of humic acids with biocides

The chemical composition of humic acids from brown coal (Aldrich) was determined by element analysis, ¹³C NMR spectroscopy, and potentiometric titration. The adsorption ability of humic acids with different biocides (cyproconasol, propiconasol, tebuconasol, irgarol 1051, and DCOIT) was studied. The adsorption ability of a mixture of biocides in aqueous solutions was higher than that of the individual components. The limiting concentration of humic acids at which adsorption of biocides was maximum was determined. Adsorption constants were calculated by the Freundlich equation for each biocide in aqueous solution.     

The forms of azeotropic rule for multidimensional diagrams of equilibrium distillation

Linear independent forms of the azeotropy rule applicable to diagrams of distillation (reaction distillation) and their fragments are established and presented as simple polyhedra of arbitrary dimensions.     

Effect of the type of molecular nonplanar structure on the chemical reactivity of NH bonds in the coordination center of porphyrin molecule

Russian Journal of General Chemistry - Effect of out-of-plane screwing of the porphyrin macrocycle (H2P) by means of tetra-meso-substitution and intracyclic N-substitution on the state of NH bonds...     

Molecular structure and mesomorphism in the series of discotic esters derived from benzene,triazine, biphenyl,and triphenylene

New mesogenic discotic triazine-based esters were synthesized and shown to form a low-temperature monotropic columnar mesophase. Using as examples the newly synthesized compounds and previously prepared discotic esters on the basis of benzene, biphenyl, and triphenylene, the effects of the nature and size of the central fragment and the number, position, length, and rigidity of peripheral substituents therein on the mesomorphic properties (in particular, the ability to form columnar and nematic mesophases) were examined. The main structural factors stabilizing columnar and nematic mesophases were revealed. Nematic mesomorphism was shown to be favored by increased size of the central fragment of the discogen molecule and by the presence of cyclohexane fragments in peripheral substituents.