High-Temperature Electrochemical Refining of Secondary Lead

The present chapter is devoted to the analysis of the obtained data on the high-temperature electrolytic production of high-purity lead from secondary lead in chloride melts. Kinetic parameters of electrode reactions were calculated, and the sequences of the metal dissolution from the double lead-antimony (Pb-Sb), lead-bismuth (Pb-Bi), and antimony-bismuth (Sb-Bi) alloys were determined. A long-term electrolysis of the antimony (battery scrap), bismuth (lead-bismuth), and lead-containing raw materials in the electrolytic cell of original construction with a porous ceramic diaphragm impregnated with the eutectic KCl-PbCl2 chloride electrolyte was performed. The anode lead alloy, containing 57.0 wt% of antimony and 36.0 wt% of bismuth, and cathode grade lead were obtained as a result of the electrolysis. The values of lead, antimony, and bismuth separation coefficients were calculated according to the values of the equilibrium potentials of the Pb-Sb, Pb-Bi, and Sb-Bi alloys. The values of separation coefficients were found to be 6.5·106–1.5·108 for a single stage at the lead extraction from the Pb-Sb and Pb-Bi alloys, which proves the possibility of a highly effective lead extraction. The value of Sb-Bi alloy separation coefficient ranges from 5.5 to 6.5, which testifies the complexity and low effectiveness of the separation process. An electrolytic refining of lead-bismuth and secondary lead, obtained from the battery scrap, was performed

Визначення максимальних охолоджуючих можливостей двокаскадних охолоджувачів при варіації геометрії гілок у каскадах

A model of the relationship between the reliability indices of two-stage TECs of various designs with the geometry of the branches of thermoelements in cascades in the ΔTmax mode with electrical series of cascades (stages) is proposed and analyzed. Relations are obtained for determining the optimal geometry of the branches of thermoelements in cascades corresponding to the maximum temperature difference. The expression allows to estimate both the maximum cooling capacities and the reliability indices of two-stage thermoelectric cooling devices of various designs. The possibility of increasing the maximum temperature drop to 4 % is shown by choosing the optimal geometry of the branches of thermoelements in cascades (stages). This is achieved under the condition that the ratio of the length to the cross-sectional area of the elements of the first stage is greater than the ratio of the length to the cross-sectional area of the second stage, which differs from the traditional equality of these ratios for a given working current. The proposed approach makes it possible to estimate the maximum temperature drop and to predict the reliability indices of two-stage thermoelectric coolers of various designs for various operating conditions and to conduct an optimized design of radio electronic equipment using cascade thermoelectric cooling devices.Рассмотрено влияние геометрии ветвей термоэлементов в каскадах на параметры и показатели надежности двухкаскадных термоэлектрических охладителей различных конструкций при последовательном электрическом соединении каскадов в режиме максимального перепада температуры. Получены соотношения для определения оптимальной геометрии ветвей термоэлементов в каскадах, соответствующей наибольшему значению перепада температуры для различных конструкций охладителей при заданном рабочем токе.Розглянуто вплив геометрії гілок термоелементів в каскадах на параметри і показники надійності двокаскадних термоелектричних охолоджувачів різних конструкцій при послідовному електричному з’єднані каскадів в режимі максимального перепаду температури. Одержані співвідношення для визначення оптимальної геометрії гілок термоелементів в каскадах, що відповідає найбільшому значенню перепаду температури для різних конструкцій охолоджувачів при заданому робочому струмі

Synthesis and Applications of Dirhodium Metallopeptides

The work describes the development of a new class of synthetic metallopeptides that features a dirhodium metal center. Combination of peptide and dirhodium properties leads to unique effects on peptide structure, peptide-protein interactions, and metal catalytic activity aimed at small molecule as well as protein substrates. Dirhodium is directly bound to carboxylate side chains of aspartate or glutamate yielding kinetically inert coordination complexes. This improves stability, allows purification and provides enhanced biocompatibility. Bridging of two side chains in the same sequence enables control of the peptide secondary structure. Dirhodium metallopeptides are applied to regulate coiled coil dimerization, stabilize and induce helical secondary structure, catalyze enantioselective organometallic transformation, and serve as ligands for proteins. These results lead to the development of hybrid organic-inorganic therapeutic agents, biological probes for study of protein-protein interactions, and enantioselective metallopeptide catalysis

Opening of Nitride Spent Nuclear Fuel

Nitride nuclear fuel (UN + 10-20% PuN) is considered a promising alternative to the widely used oxide nuclear fuel (UO2). Thermal conductivity and density of nitride fuel are ∼ 7 times and 1.3 times higher than that of oxide fuel, respectively. Nitride fuel demonstrates a good compatibility with the cladding of fuel rods made of stainless steel. Along with the development of new fuel, methods for its subsequent processing are being developed. Various options for the initial opening of nitride spent nuclear fuel (SNF) are considered in this article. The use of gaseous chlorine is technologically inconvenient and dangerous when working with radioactive substances. The electrochemical dissolution of nitride SNF cannot be realized due to the formation of a by-product - UNCl. Uranium nitride chloride is an insulator and it blocks the electrochemical process. It was found that the chlorination of nitride SNF with cadmium or lead chlorides makes it possible to carry out 100% UN → UCl3 conversion. The use of voloxidation (oxidation of nitride SNF to oxides) as the first stage of processing will make the entire technology universal, suitable for processing both nitride and oxide SNF. The choice of the method for opening SNF depends on the choice of the subsequent stages of its processing. Keywords: nitride spent nuclear fuel, SNF, chlorination, anodic dissolution, UNCl, “soft” chlorination, voloxidation, processin

Indices of flow fruit detacher with angular vibrations at inertial threshing of sesame

An experimental stand of flow rotational fruit detacher with asymmetric angular vibrations has been developed at the Agricultural University - Plovdiv (Bulgaria).   It is designed to detach fruits and seeds from the plants via inertial way. The aim of the presented paper was to evaluate the main indices of the flow fruit detacher at inertial threshing of non-dehiscent sesame varieties.  The results indicated that the detacher threshes over 95% of seeds without reducing their germination.   The seed moisture content is from 12.2% to 13.3%, which is two times higher than recommended for harvesting sesame with grain harvester.   The portion of the impurities in the threshed mixture is from 20.99% to 38.41% depending on varieties.   The detacher has reached 225 times higher threshing productivity than single person, but it is 1.4 times lower than the thresher of the grain harvester

An analysis of schools from the perspective of teachers’ affective-emotional zones

An ecological approach to space allows human constructs to become the primary prism through which to view workplaces (Nespor, 2000; Urry, 2005; Murdoch 2006). Human beings create meaning in their environments via the unity of symbolic actions and generalized meaning fields that gain their social usefulness via their affective tone. The resulting personal system becomes projected onto the world via the personal arrangement of things that are important for each person (Valsiner, 2000; Valsiner, 2005). Consequently, individual human beings constantly order parts in their environments through an affective-emotional lens when they encounter ideas, objects and spaces (Hochschild, 2003; Thrift, 2008; Boys, 2011). I use the emotional labour (Hochschild, 1983) concepts of display rules (expectations for emotional display) and feeling rules (expectations for internal affect) together with an ecological approach to space to investigate the existence of affective-emotional zones in schools. My research questions were: How do participants in a school make sense of their work environment through the lens of affective-emotional zones? How are affective-emotional zones characterized in terms of display rules and feeling rules? What challenges do teachers face when they are in particular affective-emotional zones and why? I broadly utilized a case study approach with a European international school to interview six experienced teachers using an active interview technique with open coding (Strauss and Corbin, 1998) and critical event coding (Webster and Mertova, 2007) as the principle methods of analysis. I was able to label and describe four zones that I argued are products of teacher rituals, habits, feelings (feeling rules) and emotions (display rules); the communal zone, the school zone, the student zone and the teacher zone. I further the notion of heretical feelings and emotions and describe how they constitute elements of the teacher condition. I found school affective-emotional zones are temporal as school spaces have the potential to shift from one affective-emotional zone to another as a consequence of time changes in the school day. I outline questions for future research based on my findings.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

АНАЛІЗ ДІАГНОСТИЧНИХ ПАРАМЕТРІВ ІМУНОБЛОТИНГУ ДЛЯ ВИЗНАЧЕННЯ СЕНСИБІЛІЗАЦІЇ ДО ПИЛКОВИХ АЛЕРГЕНІВ У ПАЦІЄНТІВ З РЕСПІРАТОРНИМИ ЗАХВОРЮВАННЯМИ

The aim of the study was to compare the diagnostic parameters of different systems of serological examination by immunoblot method for the determination of sensitization to allergens of pollen group in patients with respiratory allergic diseases – allergic rhinitis and bronchial asthma. Materials and methods. In the study, 88 patients with allergic rhinitis and/or atopic asthma were examined with three different methods of specific allergic diagnosis (in vivo and in vitro). Inclusion criteria were a diagnosis of allergic rhinitis (both intermittent and persistent) and/or atopic asthma. The pre-test was conducted according to the classic test method according to the normative documents with commercial allergen extracts. Western blots for the determination of IgE levels were performed using RIDA AllergyScreen test systems (R-Biopharm AG, Darmstadt, Germany) and Euroline (Euroimmun). Results and conclusions. The results of two systems for determining specific IgE for pollen allergens by the Rida AllergyScreen and Euroline methods do not always agree very well due to the systematic divergence of indicators. The results of determining specific IgE for individual allergens are generally in good agreement with each other and the results of skin testing by the prick test, however, for pollen, birch, hazel and alder pollen allergens, the Euroline system does not always match the results of skin testing by the prick test. negative results. Further analysis of the consistency and diagnostic parameters of the methods for other allergen groups is necessary to summarize all the results of the study.Метою дослідження було порівняти діагностичні параметри різних систем дослідження методом імуноблоту для визначення сенсибілізації до алергенів пилкової групи у пацієнтів з респіраторними захворюваннями – алергічним ринітом та бронхіальною астмою. Матеріали і методи. В ході дослідження 88 пацієнтів з алергічним ринітом і/або атопічною астмою були обстежені трьома різними методами специфічної алергічної діагностики (in vivo та in vitro). Критеріями включення були діагноз алергічного риніту (як інтермітуючого, так і персистуючого) та/або атопічної астми. Прик-тест проводився за класичною методикою тестування відповідно до нормативних документів з комерційними екстрактами алергенів. Вестерн-блот для визначення рівнів IgE проводили з використанням тест-систем RIDA AllergyScreen (R-Biopharm AG, Дармштадт, Німеччина) і Euroline (Euroimmun). Результати та висновки. Результати двох систем визначення специфічного IgE до алергенів пилкової групи методами Rida AllergyScreen та Euroline не завжди добре узгоджуються між собою внаслідок систематичної розбіжності показників. Результати визначення специфічних IgE до окремих алергенів в цілому добре узгоджуються між собою та з результатами шкірного тестування методом прик-тесту, втім до пилкових алергенів полину, берези, ліщини та вільхи система Euroline не завжди узгоджується з даними шкірного тестування методом прик-тесту, даючи хибно-негативні результати. Необхідний подальший аналіз узгодженості та діагностичних параметрів методів за іншими групами алергенів для узагальнення результатів дослідження

Аналіз моделі взаємозв’язку геометрії гілок термоелементів з показниками надійності каскадного охолоджувача

We examined influence of the geometry of thermoelement branches and the distribution of thermoelements in cascades of the two-cascade thermoelectric cooling devices on the reliability indicators. An analysis was conducted for the operating range of temperature difference, nominal thermal load under the mode of maximum refrigeration capacity at preset current. A mathematical model was constructed, connecting reliability indicators of the cooler and the geometry of thermoelement branches, distribution of thermoelements in the cascades, temperature differential and operating current in the cascades, and thermal load.We ran an analysis of the model, which showed that the failure rates and the probabilities of failure-free operation demonstrate clearly pronounced extrema that can be applied when designing the two-cascade thermoelectric cooling devices with enhanced reliability. The analysis of the obtained model revealed that the variation of the geometry of thermoelements and their distribution in the cascades could be employed to achieve a two-time reduction in the failure rate of a thermoelectric cooler and a corresponding increase in the probability of failure-free operation.Рассмотрено влияние геометрии ветвей термоэлементов и распределения термоэлементов в каскадах двухкаскадных термоэлектрических охлаждающих устройств на показатели надежности. Анализ проведен для рабочего диапазона перепада температур, номинальной тепловой нагрузки в режиме максимальной холодопроизводительности при заданном токе. Показано, что вариацией геометрии термоэлементов и распределением термоэлементов в каскадах можно добиться двукратного снижения интенсивности отказовРозглянуто вплив геометрії гілок термоелементів і розподілу термоелементів в каскадах двокаскадних термоелектричних охолоджуючих пристроїв на показники надійності. Аналіз наведено для робочого діапазону перепаду температур, номінального теплового навантаження в режимі максимальної холодопродуктивності при заданому струмі. Показано, що варіацією геометрії термоелементів і розподілом термоелементів в каскадах можна досягти двократного зниження інтенсивності відмо

Надійнісно-орієнтований аналіз конструкції термоелементів однокаскадного охолоджувача

The object of research is a model of the relationship between the reliability indicators of a single stage thermoelectric cooler and the geometry of the thermoelement, i.e., the ratio of its length to the cross-sectional area. Existing studies are limited to analyzing the influence of the geometry of thermoelements on the performance of cooling capacity, so the aim of the analysis is to determine the possibility of improving reliability in various modes of cooler operation. As a method of research, mathematical modeling is chosen, which allows to predict the reliability of coolers at the design stage. The influence of the geometry of thermoelements in the range from 4.5 to 20 on the power and structural parameters of the thermoelectric cooler is analyzed to select the best option for the criterion of the minimum failure rate. The analysis is performed for temperature differences in the range of the device's operability from 0 K to 60 K and operating modes from the maximum of the cooling capacity to the minimum of the failure rate taking into account energy and design constraints. An example of the use of the proposed analysis using unified thermoelectric modules is presented, which shows the possibility of reducing the relative failure rate of a thermoelectric cooler by more than 3 times due to the choice of the geometry of thermoelements. The main advantage of the proposed approach is that it is possible to increase the reliability of thermoelectric coolers without changing the production technology and used materials.Приведен сравнительный анализ основных параметров и показателей надежности однокаскадного термоэлектрического охлаждающего устройства при вариации отношения длины термоэлемента к его сечению. Анализ выполнен для перепадов температуры в диапазоне работоспособности устройства и различных режимов функционирования с учетом энергетических и конструктивных ограничений. Показана возможность выбора геометрии ветвей термоэлемента по критерию минимума интенсивности отказов.Наведено порівняльний аналіз основних параметрів і показників надійності однокаскадного термоелектричного охолоджуючого пристрою при варіації відношення довжини термоелемента до його перетину. Аналіз виконано для перепадів температури в діапазоні працездатності пристрою і різних режимів функціонування з урахуванням енергетичних і конструктивних обмежень. Показана можливість вибору геометрії гілок термоелементу за критерієм мінімуму інтенсивності відмов