41 research outputs found

    Ultradispersion microstructure and phase composition formation during intensive metal forming

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    It was shown in this paper how rate, speed and temperature of forming influence on core size, as well as influence of the cooling speed on phase composition of construction steels. Different ways of intensive deformation achievement during metal forming and in particular a flat shaped condition: equal channel angular extrusion, drawing, cross-rolling, are considered in this paper. It should be also noted that for the receipt of the required structure and mechanical properties of steel apart from the use of rational speed-temperature process parameters of forming a metal damage limit should be taken into account

    Computational power of one-way turing machines with sublogarithmic memory restrictions

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    This paper considers the well-known Turing machine model, the nondeterministic real-time Turing machine. The author proves the existence of nonregular complexity classes of languages that can be recognized by nondeterministic one-way Turing machines with sublogarithmic memory restrictions. And these complexity classes form a strict hierarchy. The author defines a special language family and shows its properties to prove that hierarchy. © 2014 Allerton Press, Inc

    Littoral phytocenoses of marshes located in different tidal conditions of the White Sea

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    This paper describes the distribution of plant communities from various associations, identified from the standpoint of the ecological-phytocenotic approach, occupying the tidal flat of low and medium marshes, which are under the influence of tide range, different values of pH and water salinity. According to the degree of pH influence, we identified acidotrophic, alkalotrophic, and indifferent phytocenoses, combined into different associations. Most associations of the estuaries with different tide range are alkalotrophic, there are noticeably fewer acidotrophic ones; a few eurytopic communities from the Phragmitetum australis, Bolboschoenetum maritimae, and Caricetum aquatilis associations are classified as indifferent. The study shows that the coastal vegetation of the marshes of the mesotidal estuaries of the White Sea develops in stable pH conditions in the range from 7.2 to 7.6. The formation of coastal vegetation is less stable in the macrotidal estuaries of the Mezen Bay, most of them form at pH = 7.0-8.3. Halophyte vegetation forms in the widest range of pH (6.2-8.3) in the marshes of microtidal estuaries in the Dvina Bay of the White Sea, which are more affected by floods than other estuaries. The halophytic vegetation of the White Sea develops in a wide range of salinity fluctuations from brackish to marine waters. However, the majority of plant associations in the rivers estuaries occupy the habitats of weakly saline waters with 10 to 25% salinity

    Определение остаточных количеств гербицида Аденго в кукурузе методом диссоциативной экстракции

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    Distribution of thiencarbazone-methyl and cyprosulfamide between chloroform and aqueous buffer solutions at pH = 3-10 has been studied at 20 ± 1 °С. Based on the experimental data obtained, the extraction sample preparation method has been developed for the determination of thiencarbazone-methyl and cyprosulfamide in corn grain and corn green mass by high performance liquid chromatography. The sample preparation method provides chromatograms where no peak interferes with the peaks of substances being determined. The recoveries of thiencarbazone-methyl and cyprosulfamide from plant matrices are in the range of 72-88%. The method allows determination of thiencarbazone-methyl and cyprosulfamide at concentrations of the maximum residue limit for corn in Republic of Belarus or below.При 20 ± 1 °С изучено распределение тиенкарбазон-метила и ципросульфамида между хлороформом и водными буферными растворами с рН 3-10. Основываясь на полученных экспериментальных данных, разработана экстракционная методика пробоподготовки зерна и зеленой массы кукурузы для последующего определения в них тиенкарбазон-метила и ципросульфамида методом высокоэффективной жидкостной хроматографии. Методика пробоподготовки обеспечивает получение хроматограмм без пиков, интерферирующих с пиками определяемых веществ, и характеризуется 72-88% извлечением тиенкарбазон-метила и ципросульфамида. Методика позволяет определять тиенкарбазон-метил и ципросульфамид на уровне, равном или ниже максимально допустимого для кукурузы, утверженного в Республике Беларусь

    Экстракция органических неэлектролитов н-гексаном из водных растворов гидрофосфата и ацетата калия

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    At a temperature of 20 ± 1 °C, the distribution of model substances of various classes of organic non-electrolytes in n-hexane – aqueous solutions of dipotassium phosphate and potassium acetate was studied. The increments of the methylene and functional groups of organic non-electrolytes are calculated. It has been shown that in case of dipotassium phosphate, the nature of the salting out effect is enhancing the structure of the salt solution and the growth of the methylene group increment. For potassium acetate, the increment of the methylene group slightly increases with increasing salt concentration, and for most functional groups it increases significantly. An explanation of the dependences of the increment values on the nature and composition of the salt solution is given.При температуре 20±1 °Cизучено распределение модельных веществ различных классов органических неэлектролитов в системах н-гексан–водные растворы гидрофосфата и ацетата калия. Рассчитаны инкременты метиленовой и функциональных групп органических неэлектролитов логарифма константы распределения. Показано, что в случае гидрофосфата калия природа эффекта высаливания в первую очередь заключается в усилении структуры солевого раствора и росте инкремента метиленовой группы. Для ацетата калия инкремент метиленовой группы незначительно растет с увеличением концентрации соли, а для большинства функциональных групп заметно увеличивается. Дано объяснение полученных зависимостей значений инкрементов от природы и состава солевого раствора

    НОВЫЕ ПРЕПАРАТЫ ДЛЯ ЗАЩИТЫ ЖИВОТНЫХ ОТ КРОВОСОСУЩИХ ДВУКРЫЛЫХ НАСЕКОМЫХ

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    Development of livestock as well as increase of milk and meat production depends considerably on prompt and qualified veterinary measures. One of the reserves of lifestock profitability rise is prevention of infectious diseases including entomosis, and animals' protection from bloodsucking dipterous insects: deer flies, mosquitos, gadflies and biting midges also known as gnats. In Belorussia dairy cows lost up to 15–20 % of milk and in single seasons up to 30–40 % due to bloodsucking dipterous insects attack. The task of present research is the study of insecticide efficacy of drugs: Delcid, Almet, Fenmet, Breeze 25 % applied as aerosols using ultra low-volume spraying when cattle in pastures are massively attacked by gnats. The repellent efficacy of drugs Breeze-Prof, Polevik, Phytolym, Tobol and Alezan spray against gad-flies are studied. While using of ultra low-volume hitch spraying of young cattle herds: 0,05 % solution of Delcid, Almet, Fenmet, Breeze 25 % at the rate of 10 ml per cattle it is found that the protective action coefficient according to average data related to gadflies family Tabanidae within first 30 minutes makes: for Delcid – 92,49 %, Almet – 100, Fenmet – 100, Breeze 25 % – 95,3 %, and within 24 hours: Delcid – 81,7 %, Almet – 71,4, Fenmet – 56,2, Breeze 25 % – 81,8 %.Изучено действие некоторых репеллентов и ин-сектицидов, рекомендуемых против гнуса. Разрабо-таны режимы их применения, проведены широкие производственные испытания и рекомендованы для практического применения наиболее эффективные и безопасные препараты на основе синтетических пире-троидов. Проведенными исследованиями изучена репеллентная эффективность против слепней семейст-ва Tabanidae новых препаратов, которые показали удовлетворительную эффективность

    Роль природы углеводородного радикала органических неэлектролитов в эффективности гидратации их функциональных групп

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    A comparative analysis of n-octane - water functional group increments (Iƒ) of organic non-electrolytes (hydrocarbons, nitrogen-, oxygen-, halogen- and sulphor-containing compounds containing n-alkyl, allyl, benzyl, vinyl, phenyl, 1-naphthyl, 2-naphthyl and 9-anthryl groups) has been performed. It has been determined that increasing the hydrocarbon chain electronegativity increases Iƒ by up to 3,7 units. For all monosubstituted groups except fluoride, replacing the alkyl group by the aryl one increases Iƒ by 0,6-1,2 units. It has been found that the most important factors determining the increase in Iƒ are the nature and number of hydrocarbon chains, bond polarity in the functional group and its possession of mobile electron pairs.Для экстракционной системы н -октан-вода проведен сравнительный анализ величин инкрементов функциональных групп органических неэлектролитов (Iф) различных классов (углеводороды, азот-, кислород-, галоген-, серосодержащие вещества), в молекулы которых входят различные углеводородные радикалы (н -алкильный, аллиль-ный, бензильный, винильный, фенильный, 1- и 2-нафтильные и 9-антрильный). Найдено, что увеличение электроотрицательности углеводородного радикала ведет к росту Iф, достигающему 3,7 единиц. Для всех монозамещенных групп кроме фтора замена алкильного радикала на арильный приводит к росту Iф на 0,6-1,2 единицы. Наиболее важными факторами, определяющими рост Iф, оказались природа и число углеводородных заместителей, полярность связей между атомами функциональной группы и наличие на этой группе подвижных электронных пар

    Computational power of one-way turing machines with sublogarithmic memory restrictions

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    This paper considers the well-known Turing machine model, the nondeterministic real-time Turing machine. The author proves the existence of nonregular complexity classes of languages that can be recognized by nondeterministic one-way Turing machines with sublogarithmic memory restrictions. And these complexity classes form a strict hierarchy. The author defines a special language family and shows its properties to prove that hierarchy. © 2014 Allerton Press, Inc

    Computational power of one-way turing machines with sublogarithmic memory restrictions

    No full text
    This paper considers the well-known Turing machine model, the nondeterministic real-time Turing machine. The author proves the existence of nonregular complexity classes of languages that can be recognized by nondeterministic one-way Turing machines with sublogarithmic memory restrictions. And these complexity classes form a strict hierarchy. The author defines a special language family and shows its properties to prove that hierarchy. © 2014 Allerton Press, Inc
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