CRUD resistant fuel cladding materials

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2013."June 2013." Cataloged from PDF version of thesis.Includes bibliographical references (pages 27-29).CRUD is a term commonly used to describe deposited corrosion products that form on the surface of fuel cladding rods during the operation of Pressurized Water Reactors (PWR). CRUD has deleterious effects on reactor operation and currently, there is no effective way to mitigate its formation. The Electric Power Research Institute (EPRI) CRUD Resistant Fuel Cladding project has the objective to study the effect of different surface modifications of Zircaloy cladding on the formation of CRUD, and ultimately minimize its effects. This modification will alter the surface chemistry and therefore the CRUD formation rate. The objective of this study was to construct a pool boiling facility at atmospheric pressure and sub-cooled boiling conditions, and test a series of samples in simulated PWR water with a high concentration of nanoparticulate CRUD precursors. After testing, ZrC was the only material out of six that did not develop dark, circular spots, which are hypothesized to be the beginnings of CRUD boiling chimneys. Further testing will be needed to confirm that it is indeed more CRUD resistant, even under realistic PWR conditions in a parallel testing facility.by Ekaterina Paramonova.S.B

Дебют. Русский язык для начинающих

The guide includes a range of material to give students the essential skills and knowledge they need for basic Russian reading, speaking, and writing (up to A2 Council of Europe language descriptor). This course is intended for a very wide audience of Russian language learners, pursuing various goals (living and studying in those countries where Russian is spoken; short-term Russian courses; traineeship; language credits, etc.).Посібник містить матеріали, що мають на меті формування у студентів базових знань і навичок російського читання, говоріння та письма (до рівня А2 за мовним дескриптором Ради Європи). Посібник призначено для широкого кола студентів, які вивчають російську мову для різних цілей (проживання та навчання в країнах, де говорять російською; короткострокові курси російської мови, стажування, отримання академічних кредитів з іноземної мови і т.д.)

Дебют. Курс русского языка для иностранных студентов.Русско-англо-французский словарь

Vocabulary of the text-book “Debut. A Course of Russian for International Students” is represented. The text-book includes a range of material to give students the essential skills and knowledge they need for Russian reading, speaking, and writing from level A2 (“Russian for beginners”) up to B1 (“Debut 1”) and B2 (“Debut 2”) according to Council of Europe language descriptor. This course is intended for a very wide audience of Russian language learners, pursuing various goals (living and studying in those countries where Russian is spoken; short-term Russian courses; traineeship; language credits, etc.).Репрезентовано лексику уроків підручника “Debut. A Course of Russian for International Students”, який містить матеріали, що мають на меті формування у студентів знань і навичок російського читання, говоріння та письма від рівня А2 (“Russian for beginners”) до рівня В1 (“Debut 1”) та рівня В2 (“Debut 2”) за мовним дескриптором Ради Європи. Призначено для широкого кола студентів, які вивчають російську мову для різних цілей (проживання та навчання в країнах, де говорять російською; короткострокові курси російської мови, стажування, отримання академічних кредитів з іноземної мови і т. ін.)

Optoelectronics and defect levels in hydroxyapatite by first-principles

Hydroxyapatite (HAp) is an important component of mammal bones and teeth, being widely used in prosthetic implants. Despite the importance of HAp in medicine, several promising applications involving this material e.g. in photo-catalysis), depend on how well we understand its fundamental properties. Among the ones that are either unknown or not known accurately we have the electronic band structure and all that relates to it, including the band gap width. We employ state-of-the-art methodologies, including density hybrid-functional theory and many-body perturbation theory within the GW approximation, to look at the optoelectronic properties of HAp. These methods are also applied to the calculation of defect levels. We find that the use of a mix of (semi-)local and exact exchange in the exchange-correlation functional, brings a drastic improvement to the band structure. Important side-effects include improvements in the description of dielectric and optical properties, not only involving conduction band (excited) states, but also the valence. We find that the highly dispersive conduction band bottom of HAp originates from anti-bonding $\sigma^{*}$ states along the $\cdots\textrm{OH-OH-}\cdots$ infinite chain, suggesting the formation of a conductive 1D-ice phase. The choice of the exchange-correlation treatment to the calculation of defect levels was also investigated by using the OH-vacancy as testing-model. We find that donor and acceptor transitions obtained within semi-local DFT differ from those of hybrid-DFT by almost 2 eV. Such a large discrepancy emphasizes the importance of using a high-quality description of the electron-electron interactions in the calculation of electronic and optical transitions of defects in HAp

Дебют. Курс русского языка для иностранных студентов

The text-book includes a range of material to give students the essential skills and knowledge they need for Russian reading, speaking, and writing from level A2 (“Russian for beginners”) up to B1 (“Debut 1”) and B2 (“Debut 2”) according to Council of Europe language descriptor. This course is intended for a very wide audience of Russian language learners, pursuing various goals (living and studying in those countries where Russian is spoken; short-term Russian courses; traineeship; language credits, etc.).Учебник содержит материалы, имеющие целью формирование у студентов знаний и навыков российского чтения, говорения и письма от уровня А2 ("Russian for beginners") до уровня В1 ("Debut 1") и уровня В2 ("Debut 2") по языковому дескриптору Совета Европы. Учебник предназначен для широкого круга студентов, которые изучают русский язык для разных целей (проживание и обучение в странах, где говорят на русском; краткосрочные курсы русского языка, стажировка, получение академических кредитов по иностранному языку и т. д.)

Problems of interpritation signs ans symbols in the process of crosscultural interaction

The article outlines the main differences between the sign and symbol. Examines various scientific approaches to the analysis of the essence of the character. The basic character traits. The attention is paid to the social nature of the origin of the symbol. Identifies the main problems faced by the communication. Discusses aspects of successful cross-cultural communication. Identifies the need for knowledge a reality for the successful sociokulturonoj mezkultutnom interaction.В статье определяются основные различия между знаком и символом. Анализируются различные научные подходы к анализу сущности символа. Рассматриваются основные признаки символа. Акцентируется внимание на социальном характере происхождения символа. Определяются основные проблемы, с которым сталкиваются участники коммуникационного взаимодействия. Рассматриваются аспекты успешной кросс-культурной коммуникации. Определяется необходимость знания иной социокультурной реальности для успешного межкультурного взаимодействия