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Copyright of Eurasian Physical Technical Journal is the property of E.A. Buketov Karaganda 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.)

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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.)

Background. In conditions of deficiency of thermal phosphoric acid, liquid complex fertilizers can be obtained based on extraction phosphorus (EPA) and nitric acids. Purpose. Study and development of the composition of liquid balanced NP fertilizers based on ammoniation of EPA and HNO3. Methodology. An I-130M ion meter was used, nitrogen was determined by the Kjeldahl method, phosphorus - photocalorimetrically. The degree of clarification of the suspensions was set depending on the duration of storage. Originality. Data on the properties of liquid NP fertilizers based on low-concentrated EPA were obtained. It has been established that the suspensions have good rheological properties and uniformity of composition. Received data. It has been shown that, depending on the pH of the pulps (4.5, 5.5 and 6.5) and the N:P2O5 ratio (1:0.5, 1:0.7 and 1:1), the products contain from 10.13 to 14.13% N and from 6.90 to 10.16% P2O5 total. of which 98.21-99.57 and 87.84-95.94% are in digestible and soluble forms. The density of liquid NP fertilizers is in the range of 1.222-1.284 g/cm³, viscosity is 2.64-6.61 cP. Their electrical conductivity is close to that of known fertilizers (47.6-54.2 mS/cm), and the saturated vapor pressure is 0.34-23.29 Pa. [ABSTRACT FROM AUTHOR]

Background. When extracting oil, groundwater is extracted mixed with it. When separating this water from oil, demulsifiers, that is, surfactants, are used. Purpose. Study of the colloidal chemical properties of the resulting new surfactant. Methodology. Based on the stalagmometric method (drop counting method), a surface tension isotherm was obtained and the adsorption characteristics of the surfactant were determined by studying the electrical conductivity. Originality. The adsorption efficiency and adsorption energy of surfactants synthesized from oleic acid were studied. Findings. Based on the dependence of surface tension on the concentration of the synthesized surfactant, it was found that its adsorption at the air/water interface has higher spontaneity than the formation of micelles. [ABSTRACT FROM AUTHOR]

Перспективными катодными материалами для среднетемпературных твердооксидных топливных элементов на основе протон- или кислородионпроводящих твердых электролитов являются слоистые двойные пероскиты (СДП) на основе редкоземельных элементов, бария и 3d-металлов, обладающие высокой электропроводностью и электрокаталитической активностью в реакции восстановления кислорода. Для улучшения функциональных характеристик СДП используют различные стратегии: а) создание композитов на основе СДП, б) частичное замещение катионов и в) создание дефицита катионов в различных позициях структуры СДП. Достоинством последней стратегии является то, что она не требует усложнения химического и, как правило, фазового состава СДП. Целью настоящего исследования явилось изучение влияния дефицита неодима и бария на структурные и электротранспортные характеристики СДП NdBaFeCo0.5Cu0.5O6–d. Образцы были получены керамическим методом и охарактеризованы при помощи рентгенофазового анализа, ИК-спектроскопии поглощения, иодометрии, электронной микроскопии, термического анализа, а также методов исследования электропроводности и термо-ЭДС. Создание до 10 мол. % вакансий в подрешетках неодима или бария слабо сказывается на величинах индекса кислородной нестехиометрии (d) и параметров элементарной ячейки производных NdBaFeCo0.5Cu0.5O6–d, однако приводит к увеличению размера кристаллитов (определенного по методам Шеррера, Уильямсона–Холла и размеранапряжения) и термической стабильности этих фаз. Величины удельной электропроводности и коэффициента Зеебека керамики, в целом, возрастают, а энергий активации процесса электропереноса уменьшаются при создании дефицита неодима или бария в ее структуре. В интервале температур 300–700 К взвешенная подвижностьносителей заряда («дырок») изменяется в пределах 0.04–0.8 см2/(В·с) и увеличивается с ростом температуры, что характерно для поляронного механизма проводимости, а их концентрация варьируется в пределах (0.1–3)·1020 см–3, экспоненциально растет с увеличением температуры и, в целом, при создании дефицита неодима или бария в структуре NdBaFeCo0.5Cu0.5O6–d

Copyright of Eurasian Physical Technical Journal is the property of E.A. Buketov Karaganda 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.)

Background. Lithium salts are obtained mainly from lithium-containing minerals. But since the lithium content in them is extremely low, the actual problem is the search for new raw sources of lithium, among which some natural brines in Uzbekistan attract attention. Purpose: To study the conditions of precipitation of lithium ions by sodium hydrogen phosphate from salt waters on the territory of Uzbekistan. Methodology. Precipitation of lithium ion by sodium hydrogen phosphate from saline waters, determination of interfering factors by conductometry and densitometry. Originality. A method has been developed for the precipitation of lithium ions from brines with sodium hydrogen phosphate at 60-70°C from a mixture of sodium, potassium, and magnesium ions. Findings. It has been established that from 0.3 N (according to sodium and potassium ions) solutions, at temperatures above 35°C, and also above 60°C, lithium ions can precipitate in the form of lithium phosphate. [ABSTRACT FROM AUTHOR]

The degree of salinization of agricultural lands in Etchmiadzin region of the Republic of Armenia was assessed. The soil samples intended for the study were taken at the end of the 2022 irrigation season their electrical conductivity was measured as the main indicator characterizing the degree of salinization. The results of the study demonstrated that depending on the area, irrigation and/or high groundwater levels caused an intensive accumulation of soluble salts in the upper horizons of agricultural soils, leading to the risk of declining soil productivity and soil degradation. Given this fact, it is very important to continuously monitor of the land in the region and suggest ways to improve it as a tool for implement a sustainable land management system. [ABSTRACT FROM AUTHOR]

The article deals with the issue of CO2 utilization by sodium hydroxide absorption. Sodium hydroxide (NaOH) is able to react with CO2 under atmospheric conditions to form carbonate or bicarbonate ions in solution. This study focuses on the absorption of CO2 by an alkaline solvent in a bubble column. Carbonate or bicarbonate ions were measured during carbonization using pH, conductivity and titration. [ABSTRACT FROM AUTHOR]

Background It is known that the low solubility of starch causes a number of problems when working with it. For this reason, obtaining a water-soluble derivative of starch, carboxymethyl starch (CMC) and its important derivatives, as well as studying its colloidal chemical properties, solves this problem. Purpose. To study the electrochemical properties of new derivatives of carboxymethyl starch in solution, their solubility, as well as their conformational changes during the transition from one state to another. Methodology Physico-chemical parameters of aqueous solutions, including electrical conductivity (in a conductometer), solution medium (in a pH meter), and swelling coefficient (by gravimetric method) of hydrogels, have been studied. Originality. It has been established that during the ionization of hydrogels, intramolecular associations are formed with the participation of metal cations and carboxylate anions, which are stabilized due to the hydrophobic interaction of the network structure of a rarely interconnected polyelectrolyte. Findings. It is shown that the process changes with a sharp change in the pH values of the medium, with an increase in the electrical conductivity of the hydrogel and the absorption coefficient. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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 aim of the paper was to research the influence of the content of polyvinyl alcohol Arkofil PPL (Archroma, Switzerland) in the electrospinning solution on the structure of nanofibrous material for medical and cosmetic purposes. As a result of an experimental study it was found that with an increase in the PVA content from 10 to 14 % the viscosity of the spinning solution increases 5 times and significantly exceeds the recommended values. Surface tension and specific volumetric electrical conductivity are almost independent on the concentration of polyvinyl alcohol and correspond to the recommended values. Experimental production of samples of nanofiber coatings and analysis of electronic images of their structure have proved that the material formed from a solution containing 14 % PVA does not contain visible defects and has a uniform distribution of nanofibers over the diameter. This indicates the advisability of using it as a fiber-forming composition for obtaining materials by the method of electrospinning. Целью работы явилось изучение влияния содержания ПВС марки Arkofil PPL (Archroma, Швейцария) в формовочном растворе и его физико-химических свойств на структуру нано- волокнистого материала медицинского, косметологического назначения. В результате экспериментального исследования установлено, что с увеличением содержания ПВС от 10 до 14 % вязкость формовочного раствора возрастает в 5 раз и значительно превышает рекомендуемые значения. Поверхностное натяжение и удельная объемная электропроводность практически не зависят от концентрации поливинилового спирта и соответствуют рекомендуемым значениям. Опытно-экспериментальная наработка образцов нановолокнистых покрытий и анализ электронных снимков их структуры доказали, что материал, сформированный из раствора со- держащего 14 % ПВС, не содержит видимых дефектов и имеет равномерное распределение нановолокон по диаметру, что свидетельствует о целесообразности его использования в качестве волокнообразующего состава для получения материалов методом электроформования.

Проведены геофизические исследования методами магнитотеллурического (МТЗ) и аудиомагнитотеллурического (АМТЗ) зондирований на территории Больше-Банной гидротермальной системы. Выполнена обработка совместно с данными полученными в ходе работ в 2015 г, что позволило уточнить структуру электропроводности района работ

Синтезированы керамические образцы нанокомпозитов состава NdBaCoFeO6–δ+ х мас. % УНТ (углеродных нанотрубок) (х = 0,5; 1,0; 2,0), в интервале температур 300–1100 К изучены их электропроводность и термо-ЭДС. Найдено, что полученные материалы являются полупроводниками p-типа, характер электропроводности которых в интервале температур 500–700 К изменяется на металлический. Установлено, что введение в NdBaCoFeO6–δ УНТ приводит к уменьшению электропроводности и увеличению коэффициента термо-ЭДС образующихся при этом нанокомпозитов, а также к увеличению энергии активации возбуждения и уменьшению энергии активации миграции основных носителей заряда в этих материалах – поляронов малого радиуса. Найдено, что значения фактора мощности керамики при температурах, близких к комнатной, возрастают, а при высоких – уменьшаются при введении в нее УНТ.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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.)

При изучении электропроводности земных недр по четырем геотраверсам Среднего Зауралья общей протяженностью ~1000 км, получен новый экспериментальный материал, демонстрирующий возможности геоэлектрики на современном уровне развития аппаратурно-методического обеспечения. По исследуемым геотраверсам построены геоэлектрические разрезы (модели) в диапазоне глубин от первых метров до 300 км. Представлена карта суммарной продольной проводимости литосферы рассматриваемой территории. Получены новые данные о расслоенности коры и верхней мантии по электрическим параметрам, позволяющие дополнить, а в ряде случаях уточнить имеющуюся геолого-геофизическую информацию о строении литосферы приуральской части Западно-Сибирской платформы.

Gallium polyphosphate was synthesized using the method of solid-phase reaction between Ga(NO3)3 and NH4H2PO4. Some properties of gallium polyphosphate and compound on its basis, such as index of refraction, density, conduct- ivity were studied. New composition of semiconductor film is developed, and the properties semiconductor film at the base of gallium polyphosphate.

Purpose. Development of the basics of technology for obtaining electrically conductive coatings using ultrasonic dispersion of carbon materials. Methods. The following methods were used in the work: ultrasonic dispersion of materials, optical microscopy, four-electrode method of measuring the electrical conductivity of coatings. The shielding effectiveness of materials was performed following ASTM D4935. The research results were processed using computer programs Microsoft office Excel and ImageJ. Results. The ultrasound treatment of carbon materials with a high specific surface area was performed. The influence of ultrasonic treatment on the efficiency of dispersion of carbon black in ethanol was established. The parameters of the process of destruction of natural graphite particles under the action of ultrasonic treatment are determined. The mechanism of structure formation into the composite material after ultrasonic treatment was proposed. The process of forming a spatial electrically conductive grid in a suspension by dispersed carbon black was established. It was shown that the use of ultrasonic treatment in the production of electromagnetic shielding materials allows to obtain oriented particles of the carbon component in the polymer matrix of the carrier and to get samples with high surface conductivity and shielding efficiency. Scientific novelty. The influence of ultrasonic treatment of carbon materials on the fabrication process, structure, and properties of shielding materials was established. Practical significance. The basics of the technology of the manufacturing process of shielding materials based on carbon materials pre-dispersed using ultrasonic treatment were developed. The optimal parameters of ultrasonic treatment of carbon materials for manufacturing shielding materials were substantiated. [ABSTRACT FROM AUTHOR]

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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 article is devoted to the results of electrical surveying carried out in the Northern Ladoga region in 2015 and 2017 by a joint team of the Geological Institute of the Kola Science Center of the Russian Academy of Sciences and the Institute of Geology of the Karelian Research Centre RAS. The set of methods included DC electrical profiling and audio-magnetotelluric sounding (AMTS). A major part of the work was electrical profiling by the method of external sliding dipole (MESD) with a 500 m step along a 130.5 km long profile crossing the entire width of the Lake Ladoga conductivity anomaly from the village of Hijtola in the west to the village of Suistamo in the east. The average depth of penetration of the MESD profiling was 150–200 m. The MESD output has enabled identification of two well conducting objects. One of them, 200 m wide, is located in the eastern margin of the Ladoga anomaly, in the area of the Janisjarvi fault zone, situated at the contact of the Northern Ladoga Proterozoic formations and Archaean rocks of the eastern frame. The second conducting object with a visible thickness of 7 km Grand anomaly is located in the middle part of the profile, on the traverse line of the settlements Elisenvaara and Ikhala. At both objects the apparent resistivity goes down to few ohm-meters or even decimal fractions. They can therefore be classified into the electronically conducting type of conductors associated with the presence of graphite- and sulfide-bearing rocks. The area of the revealed electrical conductivity anomalies was surveyed in detailed by the methods of internal sliding contact (MISK), median gradient (MG), and audio-magnetotelluric sounding (AMTS). Some outcrops were sampled for determination of the specific electrical resistance of the rocks. The article gives a consistent description of the observation technique, the results of observations and their discussion.

The article considers the influence of various parameters on the efficiency of ion exchange process to improve the quality of softening and desalination of water. It presents the dependence of the process on the duration and different characteristics of solutions by varying the concentration and nature of solute. On the basis of the results obtained the authors drawn a conclusion about the applicability of ion exchange for water purification.

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) 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.)

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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 presents the results of studies into physical-chemical and electrophysical properties of alloys of the (2Bi2O3·B2O3)100-x - (2 Bi2O3·3GeO2)x system. Frequency dependences of electrical impedance (R), dielectric permittivity (ε') and dielectric losses (tg σ) in alternating current and different temperatures were studied. It found that in samples the conductivity is mainly hopping conductivity with lengths varied between localized states. [ABSTRACT FROM AUTHOR]

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

Background. Liquid complex fertilizers (LCF) hold key position as in industry and so in agriculture. NP-fertilizers are an concentrated solution of ammonium phosphates that are necessary for greenhouse economy especially for foliar by drip irrigation. However, high cost of concentrated LCF can be clarified by application of valuable raw material such as superphosphoric acid or purified orthophosphoric acid, which are absent in Uzbekistan. One of the ways to reduce manufacture of LCF production is to apply Kyzylkum wet process of phosphoric acid (WPA). Purpose. To get liquid balanced NP-fertilizers based on ammonization WPA (17% Р2О5) by ammonia with addition ammonium nitrate and to investigate their composition and properties (density, viscosity, vapour pressure, conductivity, and degree of clarification). Methodology. The process of WPA preparation was performed through gaseous ammonia until pH 4.51 to 6.56. In order to obtain LCF brand N : P2O5 = 1 : 0.5, 1 : 0.7 and 1 : 1 in ammophos slurry ammonium nitrate was added. In the liquid NP- fertilizers content of nitrogen was determined by Kjeldahl while various forms of phosphorus was evaluated using UV-spectroscopy. Meanwhile, the density was measured with pycnometric, viscosity, kinematic methods, specific conductivity - with conductometric, vapour pressure - with dynamic methods. Whereas, degree of clarification was studied depending upon the storage time. Originality. The novel findings on physicochemical properties of liquid NP-fertilizers were obtained based on low concentrated WPA. It was established that these types of the fertilizers in comparison with standard ones have good rheological properties, homogeneous composition when adding bentonite suspension and low fluidity in a hot conditions. Findings. It was shown that depending on pH value and weight ratio of N : Р2О5 in liquid NР- fertilizers, content of N varied in a range from 12.55 to 19.20%, Р2О5total. from 9.22 to 13.07%. In them there is a high indicator of Р2О5water : Р2О5total equal to 91.37-94.31%. Increasing рН from 4.51 to 6.56 leads to raise of both density and viscosity of the slurry but weight ratio of N : Р2О5 from 1 : 0.5 to 1 : 1 and temperature from 20 to 80°С, contrary to decreasing. However, at all cases the slurries are liquid and fluid (1.241-1.363 g/сm³ and 1.20-4.99 сps). Their conductivity is (41.0-65.4 сm/m) closer to known liquid fertilizers. In a range 20-70°С vapour pressure over LCF constitutes 1.26-24.03 Pа that evidences concern low volatility in a hot condition. [ABSTRACT FROM AUTHOR]

Background. Direct emulsions (oil in water) have good, and the reverse-very low electrical conductivity. Therefore, in the study of stable water-oil emulsions (WOE) often the specific volume electrical resistance, which indirectly characterizes their colloid-chemical properties are used. Purpose. The purpose of the study is to assess the specific volume resistance as a parameter characterizing the colloid-chemical properties of oil-water emulsions. Methodology. This article concerns electrophysical research methods, in particular, the measurement of the specific volume resistance of the installation WOE. Originality. It has been established that indicators of specific volume electrical resistance (Рν) can, serves as a parameter for indirect assessment of the content of mineral salts in WOE and selection of an effective method of its destruction. Findings. The possibility of measuring the specific volume electrical resistance (Pν) for indirect assessment of the content of water, mineral salts in the WOE and the selection of an effective method of its destruction is shown. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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 article discusses the structure of the diffuse layer of colloidal particles of the soil. The authors present analytical expressions for the concentration distributions for the exchange of ions and electric potential through the thickness of the water film covering the particles. Also given the expression for the specific surface conductivity of colloidal particles. The dependence of the conductivity of the soil moisture obtained in the experiment is compared with the calculated dependence.

In the technologies of green fodder production from freshly harvested grass the moisture content control plays the important role in maintenance of high quality and decrease in losses of prepared fodder. The main field technique of moisture control is the dielectric measuring providing rapidity, comprehensible accuracy, simplicity of use and relatively low cost. The experimental measuring device for investigation of wet grasses dielectric properties based on the capacitive sensor and Agilent 4294А Precision Impedance Analyzer, over the electromagnetic field frequency range of 1-30 MHz, used for measurement of grass moisture content, was presented. Parameters of the flat ring capacitive sensor are studied, and a choice of it was proved. The necessary compacting pressure upon grass samples at calculation of their dielectric characteristics was determined. The problem of conversion the measured by the precision impedance analyzer parameters of a cable with the connected capacitive sensor into parameters of tested material has been solved. The preparation procedure of wet grasses to measuring was developed. The geometrical constant of the sensor was determined in the range of the used frequencies. It was determined the penetration depth of an electromagnetic field of the sensor into the tested material according to which the minimum thickness of the studied material layer under the sensor is limited. Dependences of grasses dielectric permittivity and electrical conductivity in the chosen frequency range were experimentally investigated at various values of moisture content and compacting pressure. By results of researches of dielectric properties of grass plants in 2013-2014 a choice of working frequency of measurements in the range of 10-15 MHz and compacting pressure of the studied grasses of 0.31-0.5 N per square meter created by the device was proved.

The work deals with the results of analytical review of the development and research of polymer composite materials with improved electro-physical and physical-mechanical properties. It found that the selection of special fillers, their variation by quantity and particle sizes in the polymer matrix can essentially affect the electro-conductivity of material and thereby regulate their electret properties on the whole. It revealed that the use of traditional fillers of carbon-black, graphite, minerals, metals, etc. in the composition of thermoplastics, reactoplastics and rubber makes it possible to prepare antistatic products, electromagnetic protective coatings, resistors, various types of current-conducting materials. The use of various light-weight fillers allows preparing lowdensity composites with higher physical-mechanical and electret properties. The spheroplastics based on siloxane elastomer began gaining a larger popularity. There is the data on carbon-blackfilled composite materials based on polyolefins which, at definite ratios, allow preparing the electroconductive products. A certain place in the review is given to the use of highly dispersed metal powders for the improvement of the electret characteristics of composites. Much attention is paid to the investigation of nanofilled composites with the use of large set of the dispersed minerals. The use of hybride polymer nanocomposites opens up new perspectives for their wider use in the production of current-conductive materials. The possibility of chemical binding of mineral filler particles with polymer matrix using the binders with conjugated double bonds provides innovative approaches to the creation of high-strength and heat-resistant electroconductive composites. It becomes obvious that the most perspective direction of preparation of materials with high electret properties must be based on mechanical-chemical synthesis of composite materials. [ABSTRACT FROM AUTHOR]

The electrical and thermal conductivities of polymer nanocomposites based on ultrahigh molecular weight polyethylene (UHMWPE) and high-density polyethylene (HDPE) were studied with a segregated and random distribution of the nanofiller, which was taken as thermally expanded graphite (TEG). The segregated structure has an ordered 3D distribution of filler particles in a framework in a polymer matrix with a high local concentration φloc, which is significantly higher than the average φ for the entire volume of the composite, φloc » φ. Concentration dependence of electrical conductivity is describedby the percolation equation with percolation thresholds-0.5 and 6.9 vol.%, critical exponent σ0-4.0 and 2.6, parameter ς0 - 530 and 0.43 S/cm for the segregated and statistical systems, respectively. Thermal conductivity for both systems is describedby a parallel model, which can be explained by the lengthy structure of the filler in the volume of the polymer. The segregated structure has a higher thermal conductivity of the filler λ, = 33 W/m-K versus λf = 15 W/m-K for the random distribution of the filler. The higher values of conductivity parameters λf σ0, and lower percolation threshold φc for the segregated structure are explained by the high local concentration of filler particles in the framework, which ensures better transfer of electrical and heat flow through the presence of direct contacts of particles in the framework compared to its random distribution. [ABSTRACT FROM AUTHOR]

Multi-component solid solutions Bi2-x(Sb, Ln)xTe3-y-zSeySz have been synthesized and their thermoelectric properties examined by means of physical-chemical analysis. It revealed that material of Bi1,88Sb0,06Nd0,06Te2,82Se0,09 composition is characterized by high thermoelectric effectiveness (Z=3,52·103 K–1). [ABSTRACT FROM AUTHOR]

Copyright of Sensor Electronics & Microsystems Technologies / Sensorna Elektronika i Microsystemni Tekhnologii is the property of I. I. Mechnikov Odessa National 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.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

Purpose. The purpose of this work was to introduce some physical characteristics of special commercial graphites and to study the properties of a number graphites of the Zavallevsky plant. Methodology. The structure of the samples was studied using optical and scanning electron microscopy with an X-ray fluorescence analyzer. The fractional composition of graphite was determined using fractional sieves, photographic and photo-sedimentation methods. The electrical conductivity was measured by a four-electrode method. Electrochemical characteristics were determined by the impedance method and the cyclic voltamperometry method. Results. A comparative analysis of special graphite natural graphites of a number of commercial firms and graphite of the Zavallievsky plant. Based on this analysis, graphite from the EUZ-M brand was chosen from domestic graphites for electrochemical studies. Originality. Electrochemical properties of electrodes with this graphite are similar to electrodes with commercial graphites. Practical value. Domestic graphite, first of all graphite EUZ-M, after additional purification has the prospect of successful use in the production of electrodes LIA. [ABSTRACT FROM AUTHOR]

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

It can be shown that independently of the individual chemical compositions of coolants, they contain positively charged particles (ions). These are necessary to compensate for the negative charge of the metal surface due to the cathode and anode areas of corrosion in the engine cooling system. These particles can enter into a dense or diffuse part of the electrical double layer formed during the metal corrosion process.