3,457 research outputs found
Pattern Transitions in Unstable Viscous Convective Medium
Convection in a thin layer of liquid (gas) with temperature dependent
viscosity between poorly heat conducting boundaries is studied within framework
of the Proctor-Sivashinsky model. This model is examined in order to study both
the flow pattern formation and the second-order structural phase transitions as
between patterns with translational invariance as well as between structures
with broken translational invariance but keeping a long-range order. The
spatial spectrum of arising patterns and estimation of their visual
defectiveness are analyzed. The relation between the density of pattern defects
and spectral characteristics of the pattern is found. We also discuss the noise
effects on the formation of pattern defects. The influence of temperature
dependence of viscosity on the process of pattern formation and structure
transformations is also discussed. It is shown that the temperature dependence
of viscosity inhibits structural transition from regular rolls to square cells
Mechanically deboned poultry meat and its role in rational and efficient use of raw materials
The growth in poultry meat production is a worldwide trend. Industrial poultry meat processing is also developing with production of a wide range of products. The technology of mechanical deboning of poultry meat and carcass parts is widely used in complex non-waste production. Mechanically deboned poultry meat (MDPM) is believed to be of inferior quality and its use is restricted by certain rules in different countries of the world. At the same time, hand separated meat is accepted as conventional meat and is not subjected to any restrictions. Over the last decades, the technology and equipment have been created that allow approximating MDPM to the category “meat” in terms of quality characteristics and reducing risks in its use upon reduction of pressure in the process of its production. However, costs of new equipment that enables producing a product with higher quality do not provide the expected efficiency, and a positive effect will be achieved only in the case of clear legal solutions regarding separation of MDPM types and methods of their classification and identification. The volume of scientific publications concerning a solution to this problematic theme is significant and scientists from many countries search for approaches to its realization differently. The difficulty in finding a solution is caused by the multifaceted nature of the problem, the character of non-standardized raw materials, a type of equipment being used to obtain different MDPM types, and various methods of investigations. Nevertheless, the performed studies create conditions for improvement of the approach to classification of different MDPM types by the production method and maximum allowable threshold values of the main standardized parameters, assessment methods, detection of their characteristics and substantiation of terminology
Development and technique of application of the multimedia technology at lectures on physics
Сформулированы основные требования, предъявляемые к презентациям на лекции. Описаны методические особенности применения мультимедийных технологий. Указаны основные проблемы внедрения данных технологий.Main requirements, which are shown to presentations at lecture, are formulated. Methodical especially of application of the multimedia technology are described. Main problems of introduction of giver technology are indicated
The influence of anomalous skin-effect no the discharge sustained by surface wave
In the present work the non self-consistent theory of the discharge sustained by SW. In the approximation of the set field analytical ratio for EEDF are found. The approached distributions of discharge parameters, such as plasma density, spatial diffusion coefficient, frequencies of elementary processes (excitation, ionization, etc.), and quantities of inelastic processes are received. It is shown, that under certain conditions the contribution to them from bounce electrons can become determining.В даній роботі побудовано самоузгоджену теорію розряду, що підтримується ПХ. У наближенні заданого поля знайдено аналітичні рішення для ФРЕЕ. Отримано наближені розподіли характеристик розряду, таких як густина плазми, коефіцієнт просторової дифузії, частоти елементарних процесів (збудження, іонізації та ін.) та кількості процесів. Показано, що за певних умов bounce електрони можуть відігравати визначну роль.В данной работе построена несамосогласованная теория разряда, поддерживаемого ПВ. В приближении заданного поля найдены аналитические решения для ФРЭЭ. Получены приближенные распределения разрядных характеристик, таких как плотность плазмы, коэффициент пространственной диффузии, частоты элементарных процессов (возбуждения, ионизации и т.п.) и количество неупругих процессов. Показано, что при определенных условиях вклад от bounce электронов может стать определяющим
Use of open electronic courses in educational activity
The use of open electronic courses is a relatively new tendency in education and it is not yet fully discovered by researchers. With its introduction a change in the structure of the educational system happens. Therefore, the article studies the specifics of the introduction of online courses, including requirements to them, as well as factors that slow down their active development. Due to it, the following methods of investigation were used as: analysis, synthesis, deduction, induction.
As an example, Kozma Minin Nizhny Novgorod State Pedagogical University - Minin University was used. Based on the study of the "Regulations on the use of open courses in the educational activities of Minin University", it was noted, in addition to the functions of the coordination group on open education, that for the trainee at the end of the course, in the case of unsatisfactory result, the possibility of the recalculation is established. This paragraph is used not by every university.
In the article we make a conclusion that open courses are a new qualitative step in the development of world education, but online courses would be much more effective as narrow-minded, adult-oriented, and deeply motivated for learning. Taken as the basis of research, Minin University showed that the university is ready for the implementation of online courses. It is one of the few universities that actively use open courses in Russia.peer-reviewe
The RING for gypsy moth control: Topical application of fragment of its nuclear polyhedrosis virus anti-apoptosis gene as insecticide
Data for increase of Lymantria dispar male survival after topical application of single-stranded RING domain fragment of IAP-3 gene of its nuclear polyhedrosis virus
This data article is related to the research article entitled “The RING for gypsy moth control: topical application of fragment of its nuclear polyhedrosis virus anti-apoptosis gene as insecticide” [1]. This article reports on significantly higher survival of gypsy moth Lymantria dispar male individuals in response to topical application of single-stranded DNA, based on RING (really interesting new gene) domain fragment of LdMNPV (L. dispar multicapsid nuclear polyhedrosis virus) IAP-3 (inhibitor of apoptosis) gene and acted as DNA insecticide
STATE FUNCTION IN UNSTABLE CONVECTIVE MEDIUM
Convection in a thin layer of liquid (gas) with temperature independent viscosity between poorly heat conducting boundaries is studied within framework of the Proctor-Sivashinsky model. We have shown by numerical simulation of the Proctor-Sivashinsky model that the state with certain topology can be described by the state function, which is the sum of squared mode of temperature spatial spectrum on the surface. The transitions between these states are characterized by splashes in time-derivative of this function and different meta-stable structures, corresponding to different values of the state function have different visually distinguishable topologies
Measurement of the decay form factors in the OKA experiment
A precise measurement of the vector and axial-vector form factors difference
in the decay is presented.
About 95K events of are selected in
the OKA experiment. The result is .
Both errors are smaller than in the previous measurements.Comment: 9 pages, 8 figure
ЭКСПРЕСС-МЕТОД ОЦЕНКИ ЭФФЕКТИВНОСТИ ПРОТИВОМОРОЗНЫХ ДОБАВОК
Usage of chemical additives while executing concrete works at negative temperatures is considered as a convenient and economical method. Range of the used antifreeze additives is rather wide. A great number of new additives are advertised but their characteristics have not been practically studied. Evaluation of the antifreeze additive efficiency is unfortunately rather long process and it does not provide comprehensive data on concrete structure formation processes. Due to this development of rapid and comprehensive methodology for construction companies is urgently required.Freezing processes of antifreeze additive aqueous solutions and hardening of cement paste with them have been investigated in the paper. The paper proposes a methodology for determination of freezing point for aqueous solutions of chemical additives of various applications. Identity of freezing point for a chemical additive aqueous solution and cement paste with an equal concentration of the additive in the paste pore fluid has been determined while taking calcium nitrate and sodium formate additives as an example. The paper demonstrates the possibility to evaluate efficiency of antifreeze additive action on the basis of kinetics in temperature changes of the cement paste with additives by its consecutive freezing and defrosting. A methodology for operational evaluation in the field of chemical additive application for concreting items at negative temperatures has been offered in the paper. The methodology does not require deficient and expensive test-equipment. It can be applied at ordinary construction companies and it is comprehensible for personnel of low-qualification. The paper shows the possibility to develop an original methodology for designing concrete structure which is based on operating efficiency determinations for single and integrated antifreeze additives.Использование химических добавок в практике ведения бетонных работ при отрицательных температурах – удобный и экономичный метод. Гамма используемых противоморозных добавок весьма широка. Рекламируются многочисленные новые добавки, характеристики которых практически не изучены. Оценка эффективности противоморозных добавок, к сожалению, длительна и не дает исчерпывающей информации о процессах структурообразования бетона, в связи с чем разработка оперативной и доступной для строительных организаций методики настоятельно необходима.Исследованы процессы замерзания водных растворов противоморозных добавок и твердения цементного теста с ними. Предложена методика определения температуры замерзания водных растворов химических добавок различного назначения. На примере добавок нитрата кальция и формиата натрия установлена идентичность температуры замерзания водного раствора химической добавки и цементного теста с равной концентрацией добавки в поровой жидкости теста. Показана возможность оценки эффективности действия противоморозных добавок по кинетике изменения температуры цементного теста с добавками посредством его последовательного замораживания и размораживания. Предложена методика оперативной оценки области применения химических добавок для бетонирования изделий при отрицательных температурах. Методика не требует дефицитного и дорогостоящего испытательного оборудования, применима в рядовых строительных организациях, доступна работникам низкой квалификации. Показана возможность разработки оригинальной методики проектирования состава бетона, основывающейся на оперативных определениях эффективности одинарных и комплексных противоморозных добавок
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