Change in the Functional Chemical Composition of the Surface and Technological Properties of Natural Quartz under the Influence of High-Voltage Nanosecond Pulses

2019 ◽  
Vol 83 (6) ◽  
pp. 668-672 ◽  
Author(s):  
I. Zh. Bunin ◽  
V. A. Chanturiya ◽  
M. V. Ryazantseva ◽  
N. E. Anashkina
2018 ◽  
Vol 82 (7) ◽  
pp. 781-785 ◽  
Author(s):  
V. A. Chanturiya ◽  
I. Zh. Bunin ◽  
M. V. Ryazantseva ◽  
E. L. Chanturiya ◽  
E. V. Koporulina ◽  
...  

2018 ◽  
Vol 82 (5) ◽  
pp. 561-566 ◽  
Author(s):  
I. Zh. Bunin ◽  
V. A. Chanturiya ◽  
M. V. Ryazantseva ◽  
E. V. Koporulina ◽  
N. E. Anashkina

Author(s):  
Pankaj Deb ◽  
Bijayalaxmi Sethi ◽  
Laxman Rongali ◽  
Manraj Meena ◽  
Rishi Verma ◽  
...  

1986 ◽  
Vol 57 (10) ◽  
pp. 2634-2635 ◽  
Author(s):  
Roberto Gratton ◽  
Sergio Mangioni ◽  
Jorge Niedbalski ◽  
Roberto Valent

2021 ◽  
Vol 2144 (1) ◽  
pp. 012004
Author(s):  
P V Panin ◽  
I A Bogachev ◽  
E A Lukina

Abstract Chemical composition, structure, and technological properties have been investigated for metal powder compositions (MPCs) of a new six-component TiAl-based alloy with Gd microadditions: Ti-31.0Al-2.5V-2.5Nb-2.5Cr-0.4Gd, wt.% (Ti-44.5Al-2V-1Nb-2Cr-0.1Gd, at.%). Three MPCs fractions (10–63, 40–100, 80–120 μm) were produced by electrode induction melting and inert gas atomization technique and targeted for the additive synthesis of parts. It is shown that the chemical composition of the MPCs for the main elements corresponds to that of the electrode. In contrast, a 1.5-fold increase of the oxygen content in the MPCs was observed, which is being the result of natural oxidation of powder particles upon air environment due to developed specific surface. It has been determined that the phase composition of the MPCs (γ+α(α2)+β) differs from the equilibrium phase composition of the electrode (γ+α2)+β0/B2) and corresponds to a rapidly quenched metastable state, which indicates high solidification rates in the atomization process, exceeding critical cooling rates of the alloy. The technological properties, specifically the powder flowability, were found to be improved for 40–100 and 80–120 μm fractions, making them applicable for additive synthesis of parts from the studied alloy by selective electron-beam melting method


Author(s):  
Е.Е. УЛЬЯНЧЕНКО

При производстве табачного сырья важную роль играет сокращение продолжительности сушки табачных листьев. Одним из способов интенсификации сушки свежеубранных табачных листьев является прием прорезания средней жилки (ПСЖ) листьев вдоль волокон. По результатам исследований 2019–2020 гг. была создана база данных табачного сырья, полученного при естественном способе сушки с применением приема ПСЖ, которая может служить информационным материалом для производителей табака. Проведена оптимизация процесса сушки табачного листа ПСЖ по показателям качества табачного сырья для расширенного диапазона сортотипов табака. Объектом исследований были сорта отечественной селекции, включенные в Государственный реестр селекционных достижений, допущенные к использованию: Самсун 85, Вирджиния 202, Юбилейный новый 142, Трапезонд 92, Трапезонд 204, Дюбек 33, Американ 287 и Крупнолистный Ильский (находится в стадии государственных испытаний). Критерием оценки эффективности применения приема ПСЖ на исследованных сортах табака являлся совокупный сравнительный анализ следующих показателей контрольных (без ПСЖ листа) и опытных образцов: уровень интенсификации сушки, показатели товарного качества, технологических свойств и химического состава полученного сырья. Установлено, что ПСЖ позволяет интенсифицировать процесс сушки в 1,3–2,46 раза в зависимости от сорта табака и положительно влияет на технологические свойства сырья, у большинства сортов увеличивается выход волокна и сохраняются объемно-упругие свойства. Динамика сушки оказывает влияние на изменение химического состава сырья. В процессе сушки за счет гидролизации солей никотина и его освобождения путем окисления кислородом воздуха уровень никотина в ряде образцов снижается в пределах 10–30%. Чем выше содержание никотина, тем выше крепость табака, грубее его вкус. Изменения углеводно-белкового соотношения в сторону повышения углеводов улучшают вкусовые характеристики сырья. По каждому исследованному сорту не удалось выявить закономерной зависимости его структуры и характера процесса сушки при ПСЖ с преобразованиями химического состава сырья. На основе анализа технологических и качественных показателей табачного сырья, представленных в разработанной базе данных по интенсификации сушки различных сортов табака с применением приема ПСЖ табачных листьев, можно планировать выбор оптимального способа сушки для каждого сорта табака, позволяющего повысить эффективность использования сырья и улучшить его качественные характеристики. In the production of tobacco raw materials, reducing the drying time of tobacco leaves plays an important role. One of the ways to intensify the drying of freshly harvested tobacco leaves is the method of cutting the middle vein (CMV) of the leaves along the fibers. Based on the results of research in 2019–2020, a database of tobacco raw materials obtained by a natural drying method using CMV reception was created, which can serve as information material for tobacco producers. The optimization of the process of drying the CMV tobacco leaf according to the quality indicators of tobacco raw materials for an expanded range of tobacco variety types was carried out. The object of research was the varieties of domestic selection included in the State Register of Breeding Achievements, approved for use: Samsun 85, Virginia 202, Yubileyny novy 142, Trapezond 92, Trapezond 204, Dubek 33, American 287 and Krupnolistnyy Ilskiy (under state testing). The criterion for evaluating the effectiveness of the use of CMV intake on the studied tobacco varieties was a cumulative comparative analysis of the following indicators of control (without CMV sheet) and experimental samples: the level of drying intensification, indicators of commercial quality, technological properties and chemical composition of the obtained raw materials. It is established that CMV allows to intensify the drying process by 1,3–2,46 times, depending on the tobacco variety and has a positive effect on the technological properties of raw materials, most varieties increase the yield of fiber and retain volume-elastic properties. The dynamics of drying affects the change in the chemical composition of raw materials. During the drying process, due to the hydrolysis of nicotine salts and its release by oxidation with air oxygen, the nicotine level in a number of samples decreases within 10–30%. The higher the nicotine content, the higher the strength of tobacco, it is coarser in taste. Changes in the carbohydrate-protein ratio in the direction of increasing carbohydrates improve the taste characteristics of raw materials. For each studied variety, it was not possible to identify a regular dependence of its structure and the nature of the drying process at CMV with transformations of the chemical composition of raw materials. Based on the analysis of technological and qualitative indicators of tobacco raw materials presented in the developed database on the intensification of drying of various varieties of tobacco using the use of CMV of tobacco leaves, it is possible to plan the choice of the optimal drying method for each variety of tobacco, which allows to increase the efficiency of using raw materials and improve its quality characteristics.


Author(s):  
S V Korotkov ◽  
V V Smorodinov ◽  
Yu V Aristov ◽  
A V Bystrov ◽  
A L Zhmodikov ◽  
...  

2020 ◽  
Vol 1013 ◽  
pp. 19-24
Author(s):  
Ming Yue Lu ◽  
Yang Li ◽  
Qing Song He ◽  
Zhen Dong Dai

Geckos can run swiftly on various surfaces, is not only related to the micro-nanostructure of their setae, but also related to the charged keratin in biological tissues of epidermis. Many gecko-inspired structural materials have been developed in order to obtain desired adhesion property. Much research has been done to improve their adhesion by changing chemical composition and optimizing micro-nanostructure, but little research has been done on the effect of surface charge. Therefore, this study aims to investigate the effect of surface charge on the adhesion of gecko-inspired materials, and to explore a new way to improve their adhesion performance. In this work, the dry adhesive materials made of polyvinylsiloxane (PVS) with mushroom-shaped pillars were polarized under high voltage. The results showed that polarized samples with the mushroom-shaped pillars facing the positive electrode have more negative charge, and the adhesion was improved a lot with increasing charge.


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