The use of immunomodulators in the surgical treatment of complicated gastric disease

While examination of 83 patients it was established that in the presence of complicated gastric and duodenal ulcer disease the secondary immune deficiency is developing, which deepens after the surgical intervention conduction. Tiotriazolin, promoting the immune system state and the blood biochemistry indexes normalization, the immune system state and the blood biochemistry indexes stimulation, hemopoiesis stimulation, the treatment results improvement, was applied for immunomodulation.     

Using gas ducts made of glass-reinforced plastic for drawing off sulfur dioxide

A gas duct for sulfur dioxide in a unit for preparing sulfuric acid is studied under production conditions. A multilayer construction for the gas duct wall is considered and results are provided for examination of the gas duct inner and outer surfaces. Favorable experience is noted for the first year of controlled operation, i.e., the glass-reinforced plastic gas duct retains safety and reliability, and this guarantees a life (up to 19 years) predicted from the results of laboratory tests. __________ Translated from Khimicheskoe i Neftegazovoe Mashinostroenie, No. 6, pp. 48–49, June, 2007.     

Multilayer AlN/AlGaN/GaN/AlGaN heterostructures for high-power field-effect transistors grown by ammonia MBE

The results of the optimization of the ammonia MBE technology of AlN/AlGaN/GaN/AlGaN heterostructures for high-power microwave field-effect transistors (FETs) are presented. The creation of technological systems of the EPN type for the deposition of group III nitrides by ammonia MBE, in combination with the development of optimum growth and postgrowth processes, make it possible to obtain AlN/AlGaN/GaN/AlGaN based heterostructures for high-power microwave FETs with the output static characteristics on the world best level. One of the main fields of application of the semiconductor heterostructures based on group III nitrides is the technology of high electron mobility transistors (HEMTs). Most investigations in this field have been devoted to the classical GaN/AlGaN structures with a single heterojunction. An alternative approach based on the use of double heterostructures with improved two-dimensional electron gas (2DEG) confinement offers a number of advantages, but such structures are usually characterized by a lower carrier mobility as compared to that in the single-junction structures. We succeeded in optimizing the double heterostructure parameters and growth conditions so as to obtain conducting channels with a 2DEG carrier mobility of 1450, 1350, and 1000 cm²/(V s) and a sheet electron density of 1.3 × 10¹³, 1.6 × 10¹³, and 2.0 × 10¹³ cm^?2, respectively. Experimental HEMTs with 1-μm-long gates based on the obtained multilayer heterostructure with a doped upper barrier layer exhibit stable current-voltage characteristics with maximum saturation current densities of about 1 A/mm and a transconductance of up to 180 mS/mm.     

Restriction polymorphism of the APOB locus in residents of the city of Tomsk

Restriction fragment length polymorphism (RFLP) of the apolipoprotein B locus was investigated in the population of Tomsk. The frequencies of alleles and haplotypes of polymorphic restriction sites XbaI, MspI, and EcoRI were determined. The parameters of linkage disequilibrium and polymorphism information content (PIC) were estimated. Comparative data on various regions of the world are shown.     

Estimation criteria for energy consumption by mining equipment in quarries

The regularities of fuel consumption by mining equipment during opencast mining are established. The criteria and procedure are proposed for calculating the rates of fuel consumption for mining equipment with diesel drive.Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 67–71, July–August, 2004.The study was conducted with financial support from the Siberian and Ural Branches of the Russian Academy of Sciences, Integration Project No. 60.     

Cracking of light hydrocarbons in the presence of electrically heated metal wires

The cracking of С₁–С₄ associated petroleum gases to ethylene and propylene in the presence of electrically heated metal wires in a tubular quartz reactor in the temperature range of 300–600°С has been studied, while providing the heating by passing an electric current at a voltage of 25–40 V, a current intensity of 7.0–9.5 A, and a power of 200–350 W through a metal wire in the form of a tungsten, molybdenum, or nichrome coil contacting with the flowing gas stream. It has been found that the coil materials are arranged in the following order with respect to the alkene yield: tungsten > molybdenum > nichrome.