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1.
It was shown that nonionic surfactants (NS) can be determined by potentiometry using liquid NS-selective electrodes. The effect of medium acidity and foreign substances on the operation of liquid NS-selective electrodes was studied. Some properties of NS-selective electrodes were determined.  相似文献   
2.
We have used x-ray fluorescence analysis to study the elemental composition of gunshot residues from smooth-bore and rifled-bore guns. We have established that it is possible to differentiate between types of projectiles (jacketed/lead), types of primers (corrosive/noncorrosive), and types of propellant powders (black/smokeless) by analysis of the elemental composition of the gunshot residues. We have shown that the mercury content in gunshot residues on the surface of the object carrying the residues steadily decreases as storage time increases. Despite this fact, mercury can be preserved as a component of gunshot residues on the object (cotton cloth) under room conditions for more than 45 days. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 3, pp. 320–325, May–June, 2006.  相似文献   
3.
We demonstrate experimentally the possibility to create and sustain a strongly ionized plasma at low gas pressures by the electromagnetic radiation of the intensity which is below the conventional breakdown level. The conditions of ignition and sustaining the plasma are found, and the plasma parameters are measured. The necessary condition for the discharge formation is strong preliminary ionization of an initial gas. Significant electron heating in the RF field, which ensures the effective gas ionization takes place due to Coulomb collisions with protoplasma ions. Such collisions are much more frequent than the electron-neutral collisions. We propose a qualitative analytical model of the discharge evolution, which describes the effects observed.  相似文献   
4.
A general form of chronological ordering is proposed, based on introduction of relativistically invariant multipoint step functions (x1, ..., xn). A system of recursive relations is established for these functions, which guarantees that the scattering matrix is unitary, covariant, and causal. The explicit form of the first four -functions is found. A comparative analysis of the known methods of chronological ordering is given.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 70–73, May, 1990.  相似文献   
5.
6.
The use of microwave techniques in scientific research is reviewed. Also some semicommercial-scale microwave units are examined.  相似文献   
7.
The homolytic addition of 1,3-oxathiolane to olefins takes place with the formation of 2-substituted 1,3-oxathiolanes and insignificant amounts of functional derivatives of sulfides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 259–263, February, 1986.  相似文献   
8.
Starting from propargyl alcohol and using the thermal Claisen rearrangement at the stage of constructing the (E)-double bond, we have synthesized trideca-4E, 7Z-dien-1-yl acetate— a component of the sex pheromone of the potato mothPhthorimaea opercucella (Zeller).Scientific-Research Institute of Fine Organic Synthesis, Academy of Sciences of the Republic of Bashkortostan, Ufa. Ufa State University of Petroleum Technology. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 452–455, May–June, 1997.  相似文献   
9.
This review generalizes work on the chemoselective synthesis of racemic methyl-branched insect pheromones and the juvenoid hydroprene from 1,5-bifunctional 3-methylpentanes produced by the acid opening of the ring of 4-methyltetrahydropyran.Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences. Scientific-Research Institute of Fine Organic Synthesis Academy of Sciences of the Republic of Bashkortostan, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 170–177, March–April, 1977.  相似文献   
10.
A new synthesis of hexadeca-7Z,11E-dien-1-yl acetate — a component of the sex pheromones of the pink bollworm (Pectinophora gossypiella) and the Angoumois grain moth (Sitotroga cerealella) — is proposed that is based on a thermal Claisen rearrangement.Scientific-Research Institute of Small-Tonnage Chemical Products and Reagents, Ufa, fax 8-(3472) 43 17 31. Ufa State Petrotechnical University. Institute of Petrochemistry and Catalysis, Academy of Sciences of the Republic of Bashkortistan, Ufa, fax-8(3472) 31 27 50. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 231–234, March–April, 1998.  相似文献   
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