EFFECT OF POLYATOMIC ALCOHOLS ON CHROME CURRENT OUTPUT AT ELECTROCHEMICAL WASTE WATER PURIFICATION

Waste water is generated in almost all industrial enterprises and is contaminated with various organic and inorganic impurities and some heavy metals to varying degrees. The aim of this study is to study the effect of polyhydric alcohols on the current efficiency in the electrochemical method of purification of industrial wastewater contaminated with various heavy metals, in particular chromate ions. The current efficiency of chromium does not exceed 18% during the electrolysis of wastewate, during the process in the presence of xylitol in an amount of 0,16%, the current efficiency increased by 21,9%, in the presence of glycerin in an amount of 0,18%, the current efficiency increased by 23,1%, in the presence of ethylene glycol in the amount of 0,20%, the current efficiency increased by 24,2%

The interfacial energy of metallic nanoparticles on the boundary with polyatomic alcohols

The interface energy is general factor, which has determined the critical size and equilibrium shape of nanoparticles, velocity of its growth and stability. The electron-statistical method, based on the Thomas-Fermi theory taking into account its current state, allows one to calculate the interfacial energy of metallic objects of different dimensions at the boundary with various media. Based on this method, we have developed a variant for calculating the interfacial energy of the system « low-dimensional metallic phase - polar dielectric film». The polyatomic alcohols (diols), used, for example, as non-aqueous media for the synthesis of metal nanoparticles, were chosen as the external medium. Also we have chosen cobalt nanocrystals as a low-dimensional metallic phase. Expressions are obtained for the external and internal contributions to the interfacial energy of the system, including the polarization correction, due to the presence of a dielectric fluid in the external region of the system. The effect of a limited dielectric fluid layer on the Gibbs boundary coordinate is analyzed. The presence of a dielectric leads to a shift of the Gibbs boundary to the external region of the system, that is, the so-called effect of «pulling the tail» of the electron density is observed. It is shown that with increasing dielectric constant, the magnitude of the polarization contribution increases rapidly in magnitude. The interface energy of a cobalt nanocrystal at the interface with polar polyatomic alcohols is calculated. The interfacial energy of the faces of cobalt nanocrystals decreases nonlinearly with an increase in the linear dimensions of the metal phase. It is shown that the dielectric coating changes the character of the dimensional and orientational dependence in comparison with the interfacial energy of macrocrystals and thin films at the interface with vacuum. With a constant size of the metal phase and an increase in the thickness of the dielectric coating, the interface energy of faces and anisotropy increase. It has been established that 1,2-ethanediol is the most effective surfactant for cobalt particles of the polyatomic alcohols considered in this paper. The dependencies obtained in this work are consistent with the literature data for the thin films of alkaline metals and other system.

Infusion therapy in the perioperative period

Background. Inadequate volume of perioperative infusion therapy (IT) is one of the predictors of postoperative complications. There are different types of infusion solutions on the pharmaceutical market: albumin, dextrans (Reopoliglukin), polyatomic alcohols (Reosorbilact, Sorbilact), hydroxyethyl starch preparations (Gekodez), modified gelatin (Volutenz), balanced colloid-hyperosmolar solution (Gekoton), etc (all listed solutions are produced by “Yuria-Pharm”). Objective. To describe the main features of perioperative IT. Materials and methods. Analysis of literature sources on this topic. Results and discussion. Inadequate IT can cause hypo- and hypervolemia, as well as slow the recovery after surgery, so the choice of infusion solution should be made very carefully. To eliminate endothelial dysfunction, which often accompanies the perioperative period, it is advisable to prescribe L-arginine (Tivortin, “Yuria-Pharm”), which acts as a substrate for the synthesis of nitric oxide. Tivortin has the following properties: membrane stabilizing, antioxidant, cytoprotective, detoxifying, endothelioprotective, anabolic, hepatoprotective, antihypoxic. L-arginine (Tivortin) also helps to correct acid-base balance, neutralizes and removes ammonia, promotes insulin synthesis and regulates blood glucose, reduces the activation and adhesion of leukocytes and platelets to the vascular endothelium. The position paper of the International Fluid Optimization Group (2015) states that in planned operations without blood loss, crystalloids can be prescribed (2 ml/kg/h for surgeries lasting >4 hours, up to 10 ml/kg/h for surgeries lasting up to 1 hour). However, the disadvantages of the most famous crystalloid (0.9 % saline) are the risk of hyperchloremic acidosis and the development of edema in case of overdose, so it is advisable to use ion-balanced solutions instead of 0.9 % NaCl. The ideal electrolyte solution should be isovolemic, isohydric, isooncotic, isoionic, and isotonic to the blood plasma. Elimination of the metabolic acidosis is an important task of perioperative IT. Soda-Bufer (“Yuria-Pharm”) can be used for this purpose, as the administration of sodium bicarbonate reduces mortality in patients with severe metabolic acidosis and acute kidney damage. To eliminate the intoxication syndrome, drugs of polyatomic alcohols (Reosorbilact) have been successfully used. Efficiency of Reosorbilact in the treatment of sepsis, peritonitis, pneumonia, burns, etc. was confirmed in the numerous studies. In addition to detoxification, Reosorbilact supports hemodynamics and microcirculation, corrects metabolic acidosis and water-electrolyte disorders, stimulates diuresis, normalizes the rheological properties of blood, which makes it the main drug for low-volume IT in the perioperative period. In turn, Xylate is the main solution in diabetes because it has antiketogenic and lipotropic properties, improves hemodynamics and microcirculation, corrects metabolic acidosis and has an osmodiuretic effect. In shock settings IT should be administered according to the ROSE concept (R (rescue) – aggressive IT; O (optimization) – support of tissue perfusion; S (stabilization) – supportive IT; E (evacuation) – deresuscitation, restoration of body functions). Conclusions. 1. Optimal IT improves the consequences of the surgery. 2. To eliminate endothelial dysfunction, it is advisable to prescribe L-arginine (Tivortin). 3. Reosorbilact is successfully used to eliminate the intoxication syndrome, which also supports hemodynamics and microcirculation, corrects metabolic acidosis and water-electrolyte disorders, which makes it the main drug for low-volume IT in the perioperative period. 4. Xylate is the main solution in diabetes because it has antiketogenic and lipotropic properties, improves hemodynamics and microcirculation. 5. In shock settings IT should be administered according to the ROSE concept (rescue, optimization, stabilization, evacuation).

Complications of the infusion therapy and their prevention

Background. Infusion solutions are divided into several groups: crystalloids, colloids (natural and artificial), polyatomic alcohols, special drugs (infusion antibiotics, analgesics, hemostatics). Each solution type has its own complications. Objective. To identify the main complications of infusions and prevention measures. Materials and methods. Analysis of the available literature on this topic. Results and discussion. After the transfusion of 1 liter of 0.9 % NaCl only 275 ml of this solution remains in plasma, and 725 ml passes into the interstitial space, causing edema. In addition, there is a risk of hyperchloraemic acidosis in case of massive transfusions. 0.9 % NaCl is inadequate in its ionic composition, has no reserve alkalinity, deepens hyperosmolar changes, so it is not used as monotherapy in daily practice. It is used as a solvent only. Ringer’s solution is also easily excreted into the interstitial space with the edema formation. It is hyperosmolar, contains a large number of chlorine ions and is excreted by the kidneys, so it should be used with caution in patients with kidney disease. A number of drugs (aminocaproic acid, amphotericin B, blood products, sodium thiopental) are incompatible with Ringer’s solution and Ringer’s lactate. In turn, 5 % glucose solution is ineffective for detoxification, liver cirrhosis and restoring the circulating blood volume in case of blood loss. Glucose infusions can increase the production of carbon dioxide and lactate, increase ischemic damage to the brain and other organs, and promote tissue edema. At present, the routine use of glucose during surgery and in critically ill patients has been completely abandoned. Preparations of polyatomic alcohols can be divided into the preparations of six-atomic alcohols – mannitol (Mannit) and sorbitol (Sorbilact, Reosorbilact) and five-atomic alcohols (xylitol – Xylate, Gluxyl, Lactoxyl) (all of the listed solutions are made by “Yuria-Pharm”). Side effects of mannitol include tachycardia, thrombophlebitis, chest pain, skin rash, dehydration, dyspepsia, fluid and electrolyte balance, and hallucinations. Hypotension is the most common complication of mannitol usage. Reosorbilact is a modern balanced infusion solution. Its effects include the hypovolemia correction, restoration of electrolyte disturbances, normalization of cardiac activity and nerve conduction, increase of alkaline blood reserve and restoration of energy balance. In case of the significant overdose Reosorbilact can cause alkalosis. Contraindications to its administration include alkalosis, cerebral hemorrhage, pulmonary embolism, and 3 grade hypertension. Xylitol is a five-atom alcohol that is rapidly incorporated into the pentose phosphate metaboliс pathway. Its side effects include the allergic reactions, hypertension, nausea, and lactic acidosis. The main disadvantage of hydroxyethyl starch (HES) drugs is the adverse effect on hemostasis (especially in drugs of the first generation). In addition, HES may impair the renal function, so they should be used in the lowest effective dose for the shortest period of time. In addition to complications associated with infusion solutions, there are complications associated with the injection procedure (hematoma, infiltration, thromboembolism, air embolism, and phlebitis). The thorough monitoring is needed to prevent the complications of all stages of infusion therapy. Such parameters as blood pressure, heart rate, blood gas composition, capillary filling time, mental status, and diuresis should be monitored. It is also necessary to carefully examine the composition of prescribed drugs and instructions for their medical use, to control the infusion rate, and to combine different drugs rationally. Conclusions. 1. There are several classes of infusion solutions, and each of them has its own advantages and disadvantages. 2. Reosorbilact is a balanced drug with the minimal risk of side effects. 3. To prevent complications, it is necessary to monitor the basic physiological parameters, to control the infusion rate, and to rationally combine different tools.

Basic principles of infusion therapy: fundamentals of fluid and electrolyte balance

Background. Infusion therapy (IT) is a method of managing the functions of the organism by influencing purposefully the morphological composition and physiological properties of blood through parenteral administration of organic and inorganic solutions. The main feature of IT is that the drug completely enters the bloodstream. Objective. To describe the main characteristics of fluid and electrolyte balance and the IT principles. Materials and methods. Analysis of the literature sources on this topic. Results and discussion. Fluid comprises about 60 % of the human body (in children – 70-80 %, in adults – 60 %, in elderly – 50-55 %). Total fluid includes intracellular and extracellular. The latter, in turn, is divided into intravascular, interstitial and transcellular. Water balance involves the balance of fluid entering the body and the fluid being excreted. The main sources of water are beverages and food, however, about 300 ml per day is formed endogenously during oxidation processes. The main ways of the fluid excretion are its excretion in urine and stool, and perspiration losses. To calculate the physiological need of water for an adult, the body weight should be multiplied by the coefficient of 30 (up to 65 years), 25 (65-75 years) or 20 (more than 75 years). IT should also take into account the pathological losses of water from fever, vomiting, diarrhea, the presence of large wounds or burns, as well as reduction of the need in water in renal or heart failure. Thus, physiological needs, fluid deficiency, fluid volume as a result of pathological loss should be added, and the oral rehydration subtracted from this sum to calculate IT volume. There are 3 degrees of dehydration severity: I degree – deficiency of 1-2 liters, thirst, oliguria; II degree – deficiency of 4-5 liters, thirst, oliguria, dry skin, mucous membranes and tongue, general weakness; III degree – deficiency of 7-8 liters, consciousness disorders, decrease in arterial pressure, shock. The first degree can be overcome by oral rehydration, the second degree – by 50 % of oral rehydration and 50 % of IT, the third degree – by 70-100 % of IT. IT solutions are divided into crystalloids, colloids, polyatomic alcohols and special drugs. Preparations of polyatomic alcohols include, in particular, Reosorbilact, Sorbilact, Xylate (“Yuria-Pharm”). Complications of IT are divided into complications associated with the violation of the technique of entering the bloodstream (injuries of blood vessels and adjacent organs, hematomas, foreign bodies in the vessels and heart, the solution misplacement out of the vascular space); complications associated with the violation of the technique of drug administration (thromboembolism, air and fat embolism); complications associated with the wrong rate of solutions’ administration (heart overload, hypervolemia, pulmonary edema, cerebral edema); complications associated with the characteristics of infusion solutions (partial hemolysis of blood cells, acid-base imbalance, disorders of blood osmolarity, local cooling of the heart); complications associated with the IT method; complications due to individual intolerance; infectious complications in case of violation of asepsis and antiseptics; infectious diseases. Criteria for IT security include the knowledge of the drug composition and understanding of the instructions for its use; multicomponentity; use of the minimum effective doses; monitoring of the excreted urine and other fluids and infused solutions; strict control of fluid balance and blood circulation parameters. Conclusions. 1. IT is an important tool in treatment of many diseases, which performs a wide range of tasks. 2. The IT solution should be chosen depending on the individual needs of the patient. 3. Criteria for IT safety include the knowledge of drug composition and instructions for its use; multicomponentity; use of the minimum effective doses; monitoring of excreted urine and infused solutions; control of fluid balance and blood circulation parameters.

IMPROVEMENT OF THERMAL OXIDATIVE CHARACTERISTICS OF DIESEL FUELS WITH ESTERS OF CYCLIC POLYATOMIC ALCOHOLS

A number of symmetric, asymmetric and complex esters of 2,2,5,5-tetramethylolcyclopentanol and 2,2,6,6-tetramethylolcyclohexanol were synthesized, their physicochemical, viscosity-temperature and thermo-oxidative properties were studied. With the addition of these esters to hydrotreated diesel fuels 0.004% it was possible to significantly improve the operational properties of fuels: to increase thermal oxidative stability, flash point and lower pour point. Proceeding from these results, the esters of cyclic polyatomic alcohols are recommended as complex additives to diesel fuels

Development and study of new lubricating compositions based on compound esters of cyclic polyatomic alcohols and industrial pentaerithritol ester

The simple and anisometric esters of 2.2.5.5-tetra methylol cyclopenthanole were synthesized with hexanole and heptanoic acids adding these esters to those of pentaerithritol and the mixture of fatty acids of С5-С9 fractions, oil compositions were prepared and studied as well. It was defined that operation characteristics of these compositions are significantly better than those of pentaerithritol ester and B-3W oil based on pentaerithritol ester. According to this data, the compositions based on polyol ester are recommended as new lubricants meeting modern standards.