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Copyright of Refrigeration Engineering & Technology is the property of Odesa National University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper considers taxes related to passenger cars and possibilities of their use in order to reduce carbon dioxide and other greenhouse gas emissions. Therefore, this paper considers ecological potential of non-recurrent taxes in connection with the purchase and registration of passenger cars, periodically charged taxes on the use of passenger car and excises in the European union. At the end, the author presents legislation related to motor vehicles taxes in Serbia and analyzes their ecological functions, and points out the shortcomings of the existing legislative solutions. [ABSTRACT FROM AUTHOR]

Decreasing negative impact of industrial emissions to the atmosphere and prolonging fossil fuel usage period are urgent issues of fuel and energy sector. In view of this problem, injection of flue gases into oil fields to increase oil recovery may be considered as environmentally safe and economically rational way for beneficial use of greenhouse gas emissions. To effectively displace oil with flue gases it is important to consider many factors: influence of composition of the flue gases and oil, miscibility conditions, injection regimes, etc. Flue gases, a product of fuel combustion in air, can be produced as a result of oil self-ignition when air is injected into a reservoir with light oil (thermal gas method). Flue gases from natural gas, fuel oil or coal combustion in power plants or other processes that burn fossil fuels can also be used for injection into the reservoir. This paper presents an analysis of the world laboratory and industrial experience in studying efficiency of oil displacement using flue gases. Conclusions are presented about optimal criteria for implementation of this process and directions for further research.

The paper describes for the first time the method of contact ureteral lithotripsy in gaseous (CO2) medium. It presents the results of a comparative study of urolithiasis patients treated with this treatment modality (study group, n=30) and with traditional contact ureteral lithotripsy in liquid medium (control group, n=30). The incidence of retrograde migration of calculus in the kidney in the study group was 0%, while it was 16.6% in the control group. Acute or exacerbation of chronic pyelonephritis was diagnosed in only 3 (10%) patients in the control group. The suggested method of contact ureteral lithotripsy is safe and provides several advantages over traditional contact ureteral lithotripsy in a fluid medium, such as: physiologic validity, absence of calculus hypermobility (increased mobility), improved visualization during surgery and high cost effectiveness.

Acid treatment is one of the main methods of stimulating the near wellbore area of the wells opening the carbonate reservoirs. Despite the extensive experience of using this technology both in Russia and abroad, as well as a significant number of studies, the success rate is hardly ever estimated at over 30%. One of the reasons for the low success rate is neglect to the changes in the physical properties of fluids during injection, interaction with the rock and the properties of the reaction products in the wellbore and the near wellbore area during the acid treatment planning. This paper discusses the main chemical reactions occurring during the interaction of hydrochloric acid with limestones and dolomites. The quantities of the substances resulting from a chemical reaction between 15% aqueous solution of acid and the carbonates have been determined. The properties (phase state, solubility, dependences of viscosity and density on pressure and temperature) of water, carbon dioxide, nitrogen, 15% aqueous solution of acid, solutions of calcium and magnesium chloride salts in the range of possible pressures and temperatures during the acid treatment were evaluated. Due to the diversity of additives used in acid solutions, the paper proves the necessity of conducting laboratory experiments to evaluate their properties under the conditions expected during the acid stimulation. Based on laboratory studies, the reaction time of 15% solution of hydrochloric acid with calcium carbonate was estimated. The impact of the chemical diverter used for primary treatments at the Badra oilfield (Iraq) on the properties of the acid solution and the reaction time was determined. The changes in the solution viscosity depending on the acid temperature and concentration were determined. The results provided in the work were used for the purposes of forecasting and evaluating the efficiency of acid treatment performed on the wells of the Badra oilfield.

Although many recently published original papers and reviews deal with plant matter decomposition rates and their controls, we are still very short in understanding of these processes in boreal and high latiude plant communities, especially in permafrost areas of our planet. First and foremost, this is holds true for winter period. Here, we present the results of 2-year field observations in south taiga and south shrub tundra ecosystems in European Russia. We pioneered in simultaneous application of two independent methods: classic mass loss estimation by litter-bag technique, and direct measurement of CO2 emission (respiration) of the same litter bags with different types of dead plant matter. Such an approach let us to reconstruct intra-seasonal dynamics of decomposition rates of the main tundra litter fractions with high temporal resolution, to estimate the partial role of different seasons and defragmentation in the process of plant matter decomposition, and to determine its factors under different temporal scale.

Copyright of Refrigeration Engineering & Technology is the property of Odesa National University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The stages of creating a circuit-cycle design of a heat-energized refrigeration machine using carbon dioxide as a working fluid are considered in the paper. The purpose of the machine development is to get cold using a low-temperature heat of enterprises, as a way of saving energy and material resources. The thermodynamic analysis for generating a machine circuit using the "cycle method", the energy and exergy analysis of parts and the machine in general, in a wide range of temperatures and pressure in the gas heater, was conducted. The analysis showed that the machine can work in a wide range of the heating source and different pressures in the gas heater, but their change affects the effectiveness of other machine parts, which affects the exergy efficiency of the machine and its parts. The obtained results of the analysis are useful for further implementation of the machine, namely modeling, design and selection of machine parts for the maximum efficiency. [ABSTRACT FROM AUTHOR]

Changing pharmacokinetics of muscle relaxants with the organ-dependent metabolism (pipecuronium), which is related with the effect exerted by carboxyperitoneum on the patient-body temperature hemostasis and on the renal function are under discussion in the paper. It was demonstrated that carboxyperitoneum affects independently the decreasing body temperature and prolonged effect duration of pipecuronium. The conclusion is that the use of muscle relaxants with the prevailing organ-dependent elimination (atracurium and cysatracurium) is more preferable versus pipecuronium in laparoscopic surgery.

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper deals with a permissible level of gas supersaturation (SS) of the body fluids and tissues used on the calculations of the decompression profiles on the basis of the features of a group set of superficially active substances skin-stabilized gas nuclei containing in the fluids. Based on the biophysical laws, there developed a criterion and relation of critical SS of the body fluids and tissues which is a specific case of an allowable SS for prolonged decompression and for that one following excursion and repeat dives. The comparison of a computed cubic relation of critical SS has of ambient pressures with linear and quadratic dependences as well as with continuous SS revealed greater adequacy of the cubic relation over a wide range of pressures.

This paper presents hygienic evaluation of carbon dioxide absorbers (zeolites KA-SM and M-11) and water absorbers (silica gel KCM-6B). It has been shown that these agents contain no toxic components, produce smell of no more than 1-2 scores at normal and high temperature, exert no stimulating effect on atmospheric microorganisms, and are safe for man. In view of this, the above absorbers can be used to purify an enclosed atmosphere.

This paper presents an overview of investigations of blood coagulation of man exposed to hypoxic hypoxia or hypoxia combined with hypercapnia. Blood coagulation changes were related to the level of hypoxia and correlated with variations in blood gases and acid-base characteristics. Prognostic criteria associated with increased coagulation in response to hypoxia were formulated. It was found that hypoxia of any degree reduced significantly the stimulation effect of epinephrine on blood coagulation and fibrinolysis. The paper discusses the relationship between respiratory and hemostatic functions of blood and mechanisms regulating its aggregation during hypoxia of various degree. It is recommended to add carbon dioxide in moderate concentrations to the hypoxic environment in order to prevent blood hypercoagulation and to increase its resistance to acute hypoxia and epinephrine-induced lesions. It is concluded that the functional state of the blood coagulation system is controlled by the concentration and proportion of oxygen and carbon dioxide, i. e. biologically active gases, in inhaled air and blood.

Accumulation of carbon dioxide in the Earth's atmosphere leads to an increase in the greenhouse effect and, as a consequence, to significant climate change. Thus, the demand to develop effective technologies of carbon dioxide conversion grows year to year. Additional reason for research in this direction is the intention of Mars exploration, since 96% of the Martian atmosphere is just carbon dioxide, which can be a source of oxygen, rocket fuel, and raw materials for further chemical utilization. In the present paper, the plasma conversion of carbon dioxide have been studied in the dc glow discharge at the gas pressure of 5 Torr in a chamber with distributed gas injection and evacuation from the same side for the case of narrow interelectrode gap. The conversion coefficient and the energy efficiency of the conversion were determined using mass spectrometry of the exhaust gas mixture in dependence on CO2 flow rate and the discharge current and voltage. Maximum conversion rate was up to 78% while the energy efficiency of the conversion was always less than 2%. It was found that the discharge at this pressure can operate in normal and abnormal modes and the transition between the modes corresponds just to the maximum value of the conversion coefficient for a given gas flow. It was shown that even in anomalous regime, when the cathode is completely covered by the discharge, the discharge contraction occurs in whole range of parameters studied. The anode glow and the plasma column outside the cathode layer occupy the central part of the discharge only that reduces the conversion efficiency. Optical emission spectra from the carbon dioxide plasma were measured in the range of 200-1000 nm, which allowed to make a conclusion that the Oxygen atom emission is mostly origins from the exited atoms appearing after dissociation rather than after electron impact excitation.

The paper analyzes and proves the feasibility of improving the energy performance of low-temperature refrigeration machines operating on R744 using cascade design with R134a, R1234yf and R717 as refrigerants based on data the scientific study of two-stage schemes analysis. At present, it is given the existing environmental prohibitions and the growing interest in the creation of low-temperature refrigeration machines operating on carbon dioxide (R744) in two-stage and cascade schemes, the presented research supplements the scientific literature on justifying the use of each of them.

Sustainable development of regions, territories, and industrial complexes is becoming increasingly important in the context of global environmental challenges. The practical realization of the sustainability challenges depends more on the implementation of specific technologies, including greenhouse emission mitigation technologies. Today, the development and scaling out of CC(U)S (carbon capture, utilization and storage) technologies seems to be one of the most realistic ways to reduce CO2 emissions. The role of CO2 is changing in the context of circular economy principles, it is no longer considered as industrial waste, but as a valuable resource. The aim of this paper is to analyze and assess the prospects for carbon dioxide utilization, as well as the cost-effectiveness of CC(U)S initiatives (using the example of a CO2-based methanol production project in Iceland) in order to explore the prerequisites and opportunities for the development of such projects in the Arctic. In order to assess the spread of technology worldwide, an analysis of foreign experience in implementing such initiatives is presented, as well as the main promising ways of carbon dioxide utilization and their key features are identified. The economic efficiency of the CO2-based methanol production project (by the example of a commercial project in Iceland) is substantiated. A general vision of the prerequisites and opportunities for the implementation of CC(U)S initiatives in the Arctic regions is presented.

During operation, concrete and reinforced concrete structures are exposed to the aggressive environment of carbon dioxide. During the reconstruction and overhaul of the berthing facilities in the coastal zone of the seas of the Far East, a weak bond strength of the “old” carbonated and “new” repair concrete has been established in the paper. The reason that prevents reliable adhesion of concrete is the formation of fragile corrosion products in the pores and on the surface of “old” concrete. Accelerated tests of concrete carbonization from exposure to carbon dioxide have been carried out in the course of the study. The structure of the carbonized cement stone has been examined using a scanning electron microscope. The research results have made it possible to assess the structure of a “healthy” cement stone and affected by carbonization. The performed analysis of concrete carbonization process, including micrographs of the samples, has shown that under the action of carbon dioxide, the surface layer with a thickness of 4 mm and more undergoes structural restructuring. Fibrous formations are destroyed, and the carbonized volume is a heap of loosely bound loose new formations and films blocking the entrances to the capillary system of concrete. They are not a reliable basis for adhesion of “new” and “old” concrete and prevent the penetration of liquid containing cement dissolution products from “new” concrete into the capillaries of the healthy structure of the “old” concrete for their reliable connection.

The use of transcritical R744 systems has become increasingly popular in recent years in a variety of different applications. For applications that span a wide temperature range between the heat source and heat sink, the use of two-stage compressor results in numerous advantages in terms of efficiency and compressor discharge temperature. This paper presents experimental data for a transcritical R744 compressor system operating at high heat rejection temperatures. A comprehensive system model was developed and validated with the experimental results. Based on this, the simulation tool was used to further optimize the system design specifically to accommodate the two-stage compression process. The optimum heat transfer area distribution has been determined to simultaneously ensure efficient intercooling at intermediate pressure and gas cooling at the high-pressure level. Simultaneously, the system was also optimized with respect to optimal intermediate pressure and the results show that for this particular system, the optimum intercooler pressure deviated substantially from the standard design approach that uses the geometric mean between suction and discharge pressures

The paper presents data on the effect of CO2 dissolved in the fermentation broth on biosynthesis of tetracycline. It was shown that there was optimal concentration of CO2 for the tetracyline-producing organism. As a result of the experiments the ranges of the optimal concentrations within 2 to 8 ml of CO2 per 100 ml of the fermentation broth were determined.

The paper deals with dynamics of antibody formation in rats. Tetanic anatoxin independently of doses and methods of administration manifests weak immunogenic properties. A complete Freind adjuvant stimulates considerably the biosynthesis of antitetanic antibodies in the primary and secondary immune responses. Electrophoresis of tetanic anatoxin polyacrylamide gel permits isolating two protein fractions, one of them migrates in the immunoglobulin G zone and its mass constitutes 73%, the other-more low-molecular and contains 27% of protein. Dynamics of the acid-base blood state indices and of antibody biosynthesis is studied on models of chronic compensated alkalosis and metabolic acidosis in rats. It is established that during the experiment, simultaneously with an insignificant increase in the total carbonic acid concentration blood, there occurs a 25-60% increase in the titres of antitetanic antibodies as compared to the control. In rats with acidosis there occurs a simultaneously decrease in the intensity of antibody biosynthesis as compared to the control (43-54%) and in the total CO2 content in blood.

The paper deals with a review of the data available in literature on the regulation of the metabolic processes in microorganisms with CO2 fixation. The main function of CO2 is traced as exemplified by different types of microorganism nutrition. The carboxylation reactions in their main forms are observed in all heterotrophic microorganisms. The experimental data relative to the heterotrophic fixation of CO2 in yeast assimilating oil carbohydrates are presented as an example. The degree of CO2 fixation under these conditions may reach 30%. Carbon of CO2 is utilized for the biomass biosynthesis.

The paper deals with studies of the effect of the 10-day complex therapy with carbostimulin application on the content of the tricarboxylic cycle and glycolysis metabolites, total lipids, cholesterol, triglycerides in blood and potassium and sodium in blood serum of patients with diabetes mellitus. It is established that under the effect of carbostimulin the content of oxaloacetate, lactate and alpha-glycerophosphate becomes normal, the lactate/pyruvate ratio elevated in diabetes decreases, which evidences for intensification of reduction processes in the cytoplasm.

The paper emphasizes common and distinctive features of carbonic acid fixation (carboxylation) in autotrophic and heterotrophic organisms as well as metabolic significance of the carboxylation reaction in the synthesis of lipids, amino acids, sugars, purine and pyrimidine nucleotides and in the functioning of a tricarboxylic cycle as an energy source in biosynthetic processes and of precursors of many vital metabolites in the organism. The paper also gives a short description of effective preparations created at the laboratory on the basis of a close dependence of biosynthetic processes in the organism on the carbonic acid fixation and the ways of their stimulation by intensifying carboxylation established by the author and his collaborators. The preparations are used for raising the productivity of farm animals, poultry and fish as well as for accelerating of blood regeneration with post-hemorrhagic and other anemias, regeneration of damaged soft and bone tissues.

The paper deals with the effect of changes in the concentration of carbonic acid in the medium on the reaction rate catalyzed with enzymes of various spectrum of the action. It is shown that the presence of carbonic acid in the medium reaction increases the rate of reactions catalyzed with lactate dehydrogenase of the rabbit liver soluble fraction, with glucose-6-phosphate dehydrogenase from yeast and trypsin. Under the same conditions the reaction rate catalyzed with glucose-6-phosphate dehydrogenase of the rabbit liver soluble fraction and with ATP-citrate (pro-3S)-lyase is considerably decreased. Changes in the carbonic acid concentrations within the physiological limits are found to have no effect on lactate dehydrogenase from the cattle heart and chymotrypsin.

The paper discusses the emergence of spontaneous hypocapnia in real aircraft flights. The flying personnel were taken under study. The hypocapnic state was diagnosed on the basis of the CO2 concentration in the alveolar air measured by a special device. In flight the CO2 concentration in the alveolar air decreased insignificantly (by 5 min Hg on the average). In emergency situations the external respiration was activated to a greater extent. It is suggested that the alveolar Pco2 level is indicative of the emotional stress.

The paper describes an automatic gas exchange control system for the autotrophic component in the life support system of heterotrophic organisms. The paper shows how the automatic control system of the autotrophic component (wheat) can be combined with that of the heterotrophic component (four white rats). The study has demonstrated a high efficiency of the automatic gas exchange control system of plants integrated with animals. The study has also provided balance characteristics of the integrated gas exchange in the plant-animal system.

The paper is concerned with a study of the sodium bicarbonate, carboxylin and hydrochloric acid effect on certain indices of acid-base balance in blood and on dynamics of antibody formation in chickens. The sodium bicarbonate or carboxylin feeding increases the carbon dioxide total content and intensity of antipseudoplague antibodies biosynthesis in the blood by 12-21 or 12.5-40%, respectively, as compared with the control. The hydrochloric acid feeding causes a decrease in the total amount of CO2 in the blood and inhibition of antibody formation by 12.7-32.8 % as compared with the control.

In this paper, we consider the corrosion issues of hot water heating systems that use contact water heaters. We show that the lack of corrosion protection methods after one-year service. It is caused by the increase of corrosivity of the environment due to saturation of the water by carbon dioxide. On the experimental side, we conduct the industrial investigations to check efficiency of the magnesium method of corrosion protection in such systems on the sample of boiler installations of the city of Alexandria. The research results show that magnesium protection allows reducing the corrosion rate to 0,05 mm per year at the starting part of the system under the conditions of the maximum flow of water through SHCHYT unit and the anodic current of magnesium dissolution on the first stages of experiment on the 4 A level. [ABSTRACT FROM AUTHOR]

The problem of intensifying the development of vast highly viscous oil resources is becoming increasingly important, urging oil and gas producers to implement state-of-the-art technologies. The conventional methods used in highly viscous oil production cannot provide a recovery factor better than 15–20 %. Therefore, the key challenge in solving this problem is to select and implement effective technologies enabling the production of such hydrocarbon resources. Some of the current technologies are based on using carbon dioxide as a stimulation agent. These technologies are successfully applied in highly viscous oil fields around the world. This paper reviews and analyses the performance of projects for carbon dioxide injection at highly viscous oil deposits in carbonate reservoirs. It provides information concerning the results of the implementation of the projects for carbon dioxide injection in the domestic and foreign fields. The project performance analysis was based on such indicators as the ratio of injected gas to produced oil volume, the increment of oil recovery factor and the oil production rate per one well. The analysis shows that the ratio of injected carbon dioxide to produced oil volume can vastly vary depending on the geological and physical characteristics of the deposits. Along with that, cyclic СО2 injection requires lesser quantities of the gas compared to dispersed injection. An increment of the oil recovery factor can reach 9.14 % at highly viscous oil production rate growth up to 3.8 m3/day/well on average.

Objectives. The objective of this paper was to compare acetylene oxidative dicarbonylation that leads to maleic anhydride with a side reaction of CO oxidation by oxygen in a PdBr2-LiBr-H2C-CH3CN system and in the presence of insoluble (Co) and soluble (Co, Fe, and Mn) phthalocyaninates (PcM).Methods. To study the oxidation of CO to CO2, a kinetics method was used; UV and IR spectroscopy was used to determine the concentrations of initial and intermediate compounds.Results. The knetics of CO to CO2 oxidation were investigated and the reactivity series of PcM in CO oxidation and maleic anhydride synthesis was characterized. A satisfactory correlation was observed between reaction rates and PcM concentration, as well as the nature of metal, in both processes. The IR measurements of concentrations of Pd(II) and Pd(I) intermediate carbonyl complexes, and CO2 concentrations, have made it possible to hypothesize the mechanism of CO2 generation. The effect of PcM concentration on the concentrations of Pd(II)(CO) in CO oxidation has been shown.Conclusions. Based on the data regarding CO oxidation and acetylene oxidative dicarbonylation, certain conditions have been proposed to effectively produce double-labeled maleic anhydride with 13C (from 13CO).

The study of iron colloid substance destruction in order to obtain the kinetic parameters is relevant for water treatment technologies. The aim of the research is to study the kinetics of iron colloid substance destruction influenced by carbon dioxide for practical use of this method in water treatment technologies for water purification step. Methods: photocolorimeter, chromatography, pH-meter, titrometry. Results: The authors have investigated iron colloid substance destruction while interacting with carbon dioxide. The process consists of the carbon dioxide absorption, destruction colloid substances followed by spontaneous precipitation of a Fe(OH)3 and desorption of CO2 from the solution. It was ascertained that the time of carbon dioxide absorption by iron colloid solution is 30 seconds, while destruction of colloids is 120 min; the time of CO2 desorption at different ways of processing solution was determined. The paper shows the defining role of organic humic substances and silicon compounds in destruction of iron colloid substances.their distabilization at pH of 4,5 allows coagulation occurrence to form a precipitate in the form of iron hydroxide (III). The activation energy of colloid substance destruction is 37,0 kJ/mol. It indicates the simultaneous limitation of this step due to the carbon dioxide diffusion and chemical reaction of its interaction with iron colloid substances.

The relevance of the research is associated with a new approach to natural gas extraction from the gas hydrate reservoir, which has a number of advantages over the previous methods. In the previously described methods, warm water was injected or pressure was lowered. This leads to high energy costs, the release of associated products (water and sand) and destruction bottom of the sea. The methane carbon dioxide substitution method considered in this paper does not have these drawbacks and can be considered as a method for conservation of carbon dioxide. The main aim is to study the features of methane replacement by carbon dioxide in gas hydrate formation during carbon dioxide injection in a porous reservoir; to carry out a numerical experiment for determining the influence of the system main parameters on pressure and temperature of the reservoir. Objects: gas hydrate reservoir of finite length, pressure and temperature of which at the initial moment of time correspond to the conditions for the stable existence of the gas hydrate. Methods. The authors have constructed a mathematical model for methane replacement by carbon dioxide in gas hydrate, taking into account the finite extent of the formation. To describe the processes of heat and mass transfer in a porous medium, a system of equations is used, including the laws of conservation of masses, energy, Darcy's law, the equation of state. Research results. The authors have constructed the mathematical model for injecting carbon dioxide into the reservoir saturated with methane and its hydrate. The numerical experiment showed that in a certain range of parameters characterizing the injected gas and the initial state of the formation, the obtained reservoir temperature in the region saturated with methane gas hydrate is below the equilibrium decomposition temperature of methane gas hydrate, which corresponds to the calculated pressure distribution. When the pressure of the injected carbon dioxide decreases or the formation pressure increases, the formation temperature rises above the equilibrium decomposition temperature of the methane hydrate. Therefore, it is necessary to introduce a second boundary of phase transitions and, accordingly, an intermediate region saturated with methane and water.

Hydronephrosis (HN) is a disease characterized by progressive distention and dilation of the pyelocaliceal system, which are caused by pelvoureteral segment stenosis and urine outflow problems. Increased hydrostatic pressure in the pyelocaliceal system gives rise to parenchymal atrophy and diminished renal function. Prior to the end of puberty, HN is more common in boys than in girls. In 20-to-40-year-old adults, HN occurs in 1 % of cases; being 1.5 times greater in women than in men. Modern urology has achieved a notable advance in treating patients with HN. Highly informative diagnostic techniques allow the detection of this disease at early stages and the choice of the most effective approach to managing the patients. The first laparoscopic pyeloplasty was performed by W. Schuessler in 1993. Up to date, it is the gold standard for HN surgery. Pelvoureteral segment stenosis and HN are often complicated by secondary lithogenesis. The quest of novel effective procedures for pyelocaliceal litholapaxy is due to technical complexities and a large number of residual calculi. This paper describes the use of flexible pyelocaliceal lithoextraction in a patient with secondary renal calculi during laparoscopic pyeloplasty.

This paper focuses on the development of the criterion of optimality of transients of the control system, based on the minimum of exergy losses in the gas cooler of carbon dioxide heat pump. It is noted that the exergy quality criterion has a clear physical meaning, as compared with the integral quadratic criterion in which the choice of the coefficients in the integrand is not justified. Mathematic model of heat exchanger is obtained using the method of solving differential equations, without going to the irrational transfer functions. The model is reduced to transfer functions of the first and second order with the delay. The continuous temperature control system of heat pump gas cooler is considered. It is shown, that one of the versions of the control system for the minimization of the proposed criterion can be a combined control system using both the principle of the negative feedback and the principle of the invariance related to a number of disturbances affecting the processes of heat transfer in the heat exchanger.

The expansion of production and the use of biofuels are determined by the legal acts of the European Commission and National legal acts encouraging such production and usage. It would be meaningful to use the mixtures of butanol and petrol in Otto engines. It was determined the possibility of producing biobutanol as a biofuel of the second generation from lignocellulose hydrolyzed to C5/C6 carbohydrates. If the 20-30% potential of lignocellulose biomass in Lithuania is used, it would be possible to produce 200-300 thousand t of biobutanol per year. Th e amount of carbon monoxide CO decreases by more than 80% when the engine works using the mixtures of petrol and butanol if compared to the CO amount of the engine working with petrol. When the engine works using the mixture of 30% butanol and petrol, the amount of carbon dioxide CO2 decreases by 4% on average, and in case it works with the mixture of 50% butanol and petrol - by 14% if compared to the CO2 amount of the engine working using petrol. When the engine works using the mixture of 30% butanol and petrol, the amount of hydrocarbons HC decreases by 26% on average, and if it works with the mixture of 50% butanol and petrol, the amount increases by some 4% if compared to the HC amount of the engine working using petrol. To generalize the results of the performed experiment, it is possible to state that the optimal mixture would consist of 70% petrol and 30% biobutanol. [ABSTRACT FROM AUTHOR]