An experimental study of electron acceleration with detuning of the bunch repetition frequency from that of an excited wake field

We have experimentally studied the excitation of wake fields in a dielectric structure by a train of relativistic electron bunches and the acceleration of subsequent bunches of the same train due to detuning of the bunch repetition frequency relative to that of the wake field excited in the dielectric structure at the Cherenkov resonance. Electron bunches of the first (leading) part of the train excite the wake wave, and bunches of the second (trailing) part of this train are shifted to the accelerating phase of the wake wave so as to gain additional energy. The possibility of controlling the number (repetition frequency) of bunches exciting the wake field in the dielectric structure and the number of subsequently accelerated bunches has been investigated by changing the value of detuning.     

Stagnating liquid biofuel developments in Russia: Present status andfuture perspectives

It is widely acknowledged that Russia possesses enormous biomass resources (Hoogwijk et al., 2005). Its vast areas devoted to agricultural production and plentiful timber resources suggest good prospects for the development of liquid biofuel production. However, no significant advances in this direction have been reported till now. None of the numerous investment projects announced at the heydays of biofuel excitement in Russia (2006−2008) are at the moment commercially operating. There are no specialised plants for the production of bioethanol and biodiesel in Russia. Little is known of the reasons for this discrepancy between biofuel potential and actual development. In investigating this discrepancy, this article analyses national developments and investigates local dynamics through a case-study in the Omsk region. It is found that the reasons for this discrepancy are not related to technological incapabilities, but are to be found in the low policy and institutional priority given to non-fossil fuel exploitation and lack of market opportunities. Sprouts of second generation liquid biofuel technologies can be identified within the state system, but it remains to be seen how strong and how long these will be supported by the Russian state.     

Stabilized treatment of recycled water in byproduct capture shop

Problems in the cooling-water cycle are addressed. Data are presented regarding the treatment of the recycled cooling water and the coking byproducts by Nalco reagents.     

Improving the life,storage, and recording of spare parts

Conclusions To reduce expenditure on acquiring and making spare parts and units and substantially reduce their consumption it is necessary to carry out more work on the standardization of components, replacing equipment and technical plant both in enterprises and in the industry as a whole. In all enterprises we should compile catalogs of components and equipment units, and determine the minimal required permanent stocks. Over a period of one to two years it will be necessary to carry out the complete centralization of the stocks of spare parts and guarantee their accountancy of consumption. To obtain a return of not less than 35–40% worn-out components for restoration and not less than 40–50% newly produced spare parts it will be necessary to subject them to strengthening by various techniques.Translated from Ogneupory, No. 6, pp. 23–27, June, 1973.     

Determination of the energy of a relativistic electron beam by measuring the thickness of the colored layer in glass

A method for determining the energy of relativistic electrons, which was used in the investigation of electromagnetic fields in plasma and dielectric structures, is described. The electron energy was determined by the extrapolated track of electrons in glass, which was estimated by the thickness of the colored (darkened) layer formed by electrons. The density distribution of the colored layer along the direction of electron motion makes it possible to record the width of the beam energy spectrum and the beam position relative to the axis of the transit channel. A stack of glass plates on which the beam is incident can be installed in the transit channel of the dielectric structure or in plasma. Each plate in the stack is placed in parallel to the beam axis. After irradiation of the plates with relativistic electrons, the colored layer depth and the density distribution are determined. Examples of determining the electron energy of a pulsed relativistic electron beam are presented. The method is insensitive to electromagnetic noise, is inexpensive, simple, and easy to use.     

High affinity recognition of serotonin transporter antagonists defined by species-scanning mutagenesis. An aromatic residue in transmembrane domain I dictates species-selective recognition of citalopram and mazindol

Human and Drosophila melanogaster serotonin (5-HT) transporters (SERTs) exhibit similar 5-HT transport kinetics and can be distinguished pharmacologically by many, but not all, biogenic amine transporter antagonists. By using human and Drosophila SERT chimeras, major determinants of potencies of two transporter antagonists, mazindol and citalopram, were tracked to the amino-terminal domains encompassing transmembrane domains I and II. Species-scanning mutagenesis, whereby amino acid substitutions are made switching residues from one species to another, was employed on the eight amino acids that differ between human and Drosophila SERTs in this region, and antagonist potencies were reassessed in 5-HT uptake assays. A single mutation in transmembrane domain I of human SERT, Y95F, shifted both citalopram and mazindol to Drosophila SERT-like potencies. Strikingly, these potency changes were in opposite directions suggesting Tyr95 contributes both positive and negative determinants of antagonist potency. To gain insight into how the Y95F mutant might influence mazindol potency, we determined how structural variants of mazindol responded to the mutation. Our studies demonstrate the importance of the hydroxyl group on the heterocyclic nucleus of mazindol for maintaining species-selective recognition of mazindol and suggest that transmembrane domain I participates in the formation of antagonist-binding sites for amine transporters.     

Determination of elemental sulfur in viscose precipitation baths by an extraction-spectrophotometric method

Conclusions The proposed extraction-photometric procedure for determining elemental sulfur content using dodecanes as the extractant and with purification of the extracts from surface-active substances with aluminum oxide can be used to determine elemental sulfur content in precipitation baths of viscose manufacture within the range from 10 to 60 mg/dm³ or higher, and also for the analysis of precipitation bath sludges.Scientific and technical documentation has been made up for metrological certification of the procedure.Translated from Khimicheskoe Volokna, No. 3, pp. 57–58, May–June, 1988.     

Study of the wear resistance and choice of the optimum material for facing mold plates

Conclusions The best base for alloys, wear resistant against abrasive action, is unstable residual austenite in combination with certain quantities of martensite. The wear resistance of material with this base is higher the higher the concentration of carbide phase. However, the use of plates made from highly alloyed irons possessing high resistance to wearing is not at present possible because of their brittleness.At present the most promising material for making facing plates for molds is forged steel Kh12 (GOST 5950-63). After tempering from 1075°C this steel contains 72% residual austenite, 16% martensite, and 12% carbides with a hardness of 53 HRC. The life of the plates made from steel Kh12 is 1.5–2 times greater than that of plates made from steel Kh12F1. At the same time steel Kh12 is almost twice as cheap as steel Kh12F1, and the production technology for the facing plates from both these steels is practically identical; we recommend steel Kh12 for wide use in production.Translated from Ogneupory, No. 7, pp. 7–9, July, 1973.