Fluoroaliphatic esters of fluorosulfonic acid. 4. Reactions of α-fluorosulfatoperfluoro ketones with nucleophilic reagents

-Fluorosulfatoperfluoroethyl isopropyl ketone I and fluorosulfatopentafluoroacetone II react with alkali metal chlorides and bromides to form the corresponding -haloperfluoro ketones as a result of direct nucleophilic substitution.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2066–2069, September, 1990.     

Magnetic resonance studies of the deuteration effect on intersystem crossing in the anthracene molecule

The intersystem crossing decay constants from the ³B_2u state into the ground state of anthracene-d₁₀ in a phenazine crystal have been determined by magnetic resonance techniques at 1.5°K both at high magnetic field and, by a parameterization procedure, at zero magnetic field. A comparison of the anthracene-d₁₀ zero-field results with those for anthracene-h₁₀ show the effects of deuterium substitution to be largest for the in-plane spin levels of the anthracene triplet state.     

Synthetic studies in the field of the porphyrins. synthesis of a mesoporphyrin and of a diacetyldeuteroporhyrin

A method is proposed for the synthesis of porphyrins based on the cyclization of a tetrapyrrole system with methyl and formyl groups at the ends of the molecule. The synthesis of mesoporphyrin IX and diacetyldeuteroporphyrin IX has been effected.     

Mathematical model of substance active transport via cytoplasmic membrane of microbial cell along concentration gradient

Applied Biochemistry and Biotechnology - Considering the process of methane generation by methanogenic bacteria as an example, the model describes the distribution of methane concentration inside...     

Adsorption and thermodynamic properties of active sites of a pyrogenic aluminium oxide surface

Differential isosteric adsorption heats and entropies of adsorption of both n-pentane and diethyl ether on hydrated and dehydrated surfaces of pyrogenic alumina (S=140 m²/g) in the coverage range of 0.15–1.0 have been calculated from the adsorption isotherms.     

Laser photolysis study of the triplet states of nitroaromatic amides

The spectrokinetic indices of the triplet states of nitroaromatic amides were established. The quenching of triplet states by tertiary aromatic amines in apolar solvents leads to the formation of triplet exciplexes. A charge transfer state makes the major contribution to the structure of these exciplexes. Hydrogen atom transfer proceeds efficiently in the case of secondary aromatic amines, leading to the formation of the corresponding neutral radicals.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1912–1915, August, 1989.     

Electrocatalysis by foreign metal monolayers: Oxidation of formic acid on platinum

It was demonstrated that some foreign metal monolayers formed by underpotential deposition have pronounced catalytic effects on the oxidation of formic acid on platinum. The explanation of these effects was sought within the framewor of existing data on the formic acid oxidation and the underpotential deposition. It was found that the catalytic effect of foreign metal monolayers originates in the decrease of hydrogen adsorption thus preventing the formation of the main poisoning species COH. At the same time these experiments confirm the previously postulated mechanism of formation of the poisoning species involving adsorbed hydrogen.     

High-tech breakthrough DNA scanner for reading sequence and detecting gene mutation

The 17″×14″ X-ray film, gels, and blots are widely used in DNA research. However, DNA laser scanners are costly and unaffordable for the majority of surveyed biotech scientists who need it. The high-tech breakthrough analytical personal scanner (PS) presented in this report is an inexpensive 1 lb hand-held scanner priced at 2–4% of the bulky and costly 30–95 lb conventional laser scanners. This PS scanner is affordable from an operation budget and biotechnologists, who originate most science breakthroughs, can acquire it to enhance their speed, accuracy, and productivity. Compared to conventional laser scanners that are currently available only through hard-to-get capital-equipment budgets, the new PS scanner offers improved spatial resolution of 20 μm, higher speed (scan up to 17″×14″ molecular X-ray film in 48 s), 1–32,768 gray levels (16-bits), student routines, versatility, and, most important affordability. Its programs image the film, read DNA sequences automatically, and detect gene mutation. In parallel to the wide laboratory use of PC computers instead of mainframes, this PS scanner might become an integral part of a PC-PS powerful and cost-effective system where the PS performs the digital imaging and the PC acts on the data.