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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   
3.
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   
4.
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   
5.
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   
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The use of microwave techniques in scientific research is reviewed. Also some semicommercial-scale microwave units are examined.  相似文献   
8.
Smoothness/defectiveness of the carbon material surface is a key issue for many applications, spanning from electronics to reinforced materials, adsorbents and catalysis. Several surface defects cannot be observed with conventional analytic techniques, thus requiring the development of a new imaging approach. Here, we evaluate a convenient method for mapping such “hidden” defects on the surface of carbon materials using 1–5 nm metal nanoparticles as markers. A direct relationship between the presence of defects and the ordering of nanoparticles was studied experimentally and modeled using quantum chemistry calculations and Monte Carlo simulations. An automated pipeline for analyzing microscopic images is described: the degree of smoothness of experimental images was determined by a classification neural network, and then the images were searched for specific types of defects using a segmentation neural network. An informative set of features was generated from both networks: high-dimensional embeddings of image patches and statics of defect distribution.

Defectiveness of carbon material surface is a key issue for many applications. Pd-nanoparticle SEM imaging was used to highlight “hidden” defects and analyzed by neural networks to solve order/disorder classification and defect segmentation tasks.  相似文献   
9.
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   
10.
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   
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