Magnetization of carbonaceous asteroids by nebular fields and the origin of CM chondrites

The solar nebula carried a strong magnetic field that had a stable intensity and direction for periods of a thousand years or more1. The solar nebular field may have produced post-accretional magnetization in at least two groups of meteorites, CM and CV chondrites [1–3], which originated from planetesimals that may have underwent aqueous alteration before gas in the solar nebula dissipated [1,3]. Magnetic minerals produced during aqueous alteration, such as magnetite and pyrrhotite [4], could acquire a chemical remanent magnetization from that nebular field [3]. However, many questions about the size, composition, formation time, and, ultimately, identity of the parent bodies that produced magnetized CM and CV chondrites await answers—including whether a parent body might exhibit a detectable magnetic field today. Here, we use thermal evolution models to show that planetesimals that formed between a few Myr after CAIs and ~1 Myr before the nebular gas dissipated could acquire from the nebular field, and retain until today, a chemical remanent magnetization throughout nearly their entire volume. Hence, in-situ magnetometer measurements of C-type asteroids could help link magnetized asteroids to magnetized meteorites. Specifically, a future mission could search for a magnetic field as part of testing the hypothesis that 2 Pallas is the parent body of the CM chondrites [5]. Overall, large carbonaceous asteroids might record ancient magnetic fields in magnetic remanence that produces strong modern magnetic fields, even without a metallic core that once hosted a dynamo.

Hydraulic Planning in Insular Urban Territories: The Case of Madeira Island—São Vicente

This study aims to examine the flood propensity of the main watercourse of São Vicente drainage basin and, if relevant, to propose two methodologies to alleviate the impacts, i.e., detention basin sizing and riverbed roughness coefficient adjustment. Geomorphological data were obtained from the watershed characterization process and used through the SIG ArcGIS software for the flood propensity assessment and then for the calculation of the expected peak flow rate for a return period of 100 years through the Gumbel Distribution. Subsequently, the drainage capacity of the river mouth was verified using the Manning-Strickler equation, in order to establish whether the river mouth of the watershed has the capacity to drain the entire volume of rainwater in a severe flood event. In summary, it was possible to conclude that São Vicente’s watershed river mouth is not able to completely drain the rain flow for the established return period. Thus, its drainage capacity was guaranteed by modifying the walls and streambed roughness coefficient and by sizing the detention basin using the Dutch and the Simplified Triangular Hydrograph methods.

3D Visualization of the Results of Using Modern Ofa Technology on the Example of Real Boiler

The leading place in the world for environmental protection is currently occupied by the protection of the air basin. And the main sources of atmospheric pollution are industrial enterprises, motor transport and thermal power plants. Thus, there is an obvious need to increase attention to the problems of the innovation sector, mainly in the areas of technical improvement of heat and power industry enterprises. Therefore, the study of the problems of reducing the amount of harmful emissions into the atmosphere, control and regulation of its quality, as well as the study of new various methods of innovative development of thermal power is an urgent task at present, requiring a serious scientific approach. In the proposed work, computer experiments were carried out in the field of innovative energy production technologies (the use of modern "sharp blast" OFA technology) at a specific thermal power facility of the enterprise of the Republic of Kazakhstan. During the experiment, various ways of supplying additional air through OFA nozzles were investigated: OFA=0% (basic version without additional air supply), OFA=10% and OFA=18%. For these three modes, a comparative analysis of the aerodynamics of the furnace part of the boiler was performed according to the obtained distributions of the temperature and concentration fields of nitrogen oxide NO over the entire volume of the combustion chamber. The results obtained were compared with experimental data obtained during experiments conducted directly at the CHP.

3D visualization of the results of using modern OFA technology on the example of real boiler

The leading place in the world for environmental protection is currently occupied by the protectionof the air basin. And the main sources of atmospheric pollution are industrial enterprises, motor transport andthermal power plants. Thus, there is an obvious need to increase attention to the problems of the innovationsector, mainly in the areas of technical improvement of heat and power industry enterprises. Therefore, thestudy of the problems of reducing the amount of harmful emissions into the atmosphere, control and regulationof its quality, as well as the study of new various methods of innovative development of thermal power is anurgent task at present, requiring a serious scientific approach. In the proposed work, computer experimentswere carried out in the field of innovative energy production technologies (the use of modern "sharp blast"OFA technology) at a specific thermal power facility of the enterprise of the Republic of Kazakhstan. Duringthe experiment, various ways of supplying additional air through OFA nozzles were investigated: OFA=0%(basic version without additional air supply), OFA=10% and OFA=18%. For these three modes, a comparativeanalysis of the aerodynamics of the furnace part of the boiler was performed according to the obtaineddistributions of the temperature and concentration fields of nitrogen oxide NO over the entire volume of thecombustion chamber. The results obtained were compared with experimental data obtained during experimentsconducted directly at the CHP.

SEPARATION OF PARTICLES IN POLYDISPERSE NANOSUSPENSION IN THE LASER RADIATION FIELD

На основе стационарного решения уравнения диффузии изучена сепарация наночастиц в прозрачной полидисперсной водной суспензии с различными типами распределений по размерам под действием силы светового давления, возникающей в поле лазерного излучения интенсивностью 0,5 - 500 кВт/см. Установлено, что на дно кюветы преимущественно будут осаждаться частицы радиусом более 100 нм, а концентрация более мелких наночастиц во всем объеме суспензии останется без изменений. В случае симметричного начальное распределения наночастиц по размерам воздействие интенсивного светового пучка на суспензию приводит к нарушению симметрии кривой функции распределения, а также смещению максимума в область меньших размеров частиц на облучаемой поверхности. Если начальное распределение по размерам имеет несимметричный характер, исходное одномодовое распределение частиц по размерам трансформируется в двумодовое. Данная методика может быть использована для выделения наночастиц определенных размеров в зависимости от плотности мощности излучения. On the basis of a stationary solution of a diffusion equation separation of nanoparticles in a transparent polydisperse aqueous suspension with different types of size distributions was studied under the action of the light pressure arising in the laser radiation field with the intensity of 0,5 - 500 kW/cm. It was found that particles with a radius of more than 100 nm will mainly be precipitated at the bottom of the cell, and the concentration of smaller nanoparticles in the entire volume of the suspension will remain unchanged. In the case of a symmetrical initial distribution of nanoparticles size, the effect of a light beam with high intensity on the suspension leads to a violation of the symmetry of the distribution function curve, as well as a shift of the maximum to the region of smaller particle sizes on the irradiated surface. If the initial size distribution is asymmetric, the initial single-mode particle size distribution is transformed into a two-mode one. This technique can be used to isolate nanoparticles of certain sizes depending on the power density of the radiation.

Introduction: Why a Social Representations Perspective?

This chapter introduces the social representations perspective that forms the background of the entire volume, presenting the social-psychological gaze (regard psychosocial): the acknowledgment that the knowledge of a social object necessarily requires the mediation of an Alter, a “thirdness.” From this premise, specific ways of studying change and continuity in meaning-making derive, putting change at the forefront as well as concerns about the role of the researcher along the path. After considering these features, the chapter briefly presents the various parts that compose the book and the single chapters. From a social representations stance or from cognate perspectives, several keywords and topics are encountered, both on a theoretical side and with empirical examples, addressing social issues in domains such as health, aging, inequalities, environment, and community.

Root CT Segmentation Using Incremental Learning Methodology on Improved Multiple Resolution Images

The real-time issue of reliability segmenting root structure while using X-Ray Computed Tomography (CT) images is addressed in this work. A deep learning approach is proposed using a novel framework, involving decoders and encoders. The encoders-decoders framework is useful to improve multiple resolution by means of upsampling and downsampling images. The methodology of the work is enhanced by incorporating network branches with individual tasks using low-resolution context information and high-resolution segmentation. In large volumetric images, it is possible to resolve small root details by implementing a memory efficient system, resulting in the formation of a complete network. The proposed work, recent image analysis tool developed for root CT segmented is compared with several other previously existing methodology and it is found that this methodology is more efficient. Quantitatively and qualitatively, it is found that a multiresolution approach provides high accuracy in a shallower network with a large receptive field or deep network in a small receptive field. An incremental learning approach is also embedded to enhance the performance of the system. Moreover, it is also capable of detecting fine and large root materials in the entire volume. The proposed work is fully automated and doesn’t require user interaction.

THERMODYNAMIC PROPERTIES AND THE EQUATION OF STATE OF COPPER

Высокотемпературное уравнение состояния меди получено с использованием экспериментальных данных по термодинамическим свойствам, объемному термическому расширению, сжимаемости, температурной зависимости модуля объемного сжатия. Весь объем экспериментальных данных оптимизирован с использованием температурно-зависящего уравнения Тайта в диапазоне давлений до 2000 кбар и температур от 20-50 K до температуры плавления. Температурная зависимость термодинамических и термофизических параметров описана с использованием расширенной модели Эйнштейна. Полученное уравнение состояния хорошо описывает весь объем экспериментальных данных в пределах погрешности измерений отдельных величин. The high-temperature equation of state of copper is obtained using experimental data on thermodynamic properties, volumetric thermal expansion, compressibility, temperature dependence of the volumetric compression modulus. The entire volume of experimental data is optimized using the temperature-dependent Tate equation in the pressure range up to 2000 kbar and temperatures from 20-50 K to the melting point. The temperature dependence of thermodynamic and thermophysical parameters is described using the extended Einstein model. The resulting equation of state describes well the entire volume of experimental data within the measurement error of individual quantities.

THERMODYNAMIC PROPERTIES AND THE EQUATION OF STATE OF LEAD

Институт проблем химико-энергетических технологий Сибирского отделения Российской академии наук (ИПХЭТ СО РАН), г. БийскВысокотемпературное уравнение состояния (УС) твердого свинца с гранецентрированной кубической структурой решетки получено с использованием экспериментальных данных по термодинамическим свойствам, термическому расширению, сжимаемости, температурной зависимости модуля объемного сжатия. Весь объем экспериментальных данных оптимизирован с использованием температурно-зависящего УС Тайта в диапазоне давлений 0-130 кбар. Температурная зависимость термодинамических и термофизических параметров описана с использованием расширенной модели Эйнштейна. Полученное УС хорошо описывает весь объем экспериментальных данных в пределах погрешностей измерения отдельных величин. The high-temperature equation of state (US) of solid lead with a face-centered cubic lattice structure is obtained using experimental data on thermodynamic properties, thermal expansion, compressibility, and temperature dependence of the volume compression modulus. The entire volume of experimental data is optimized using a temperature-dependent Void in the pressure range 0-130 kbar. The temperature dependence of thermodynamic and thermophysical parameters is described using the extended Einstein model. The obtained US well describes the entire volume of experimental data within the measurement errors of individual quantities.

Study of Ti – Al based high-temperature cermet filters

Operation in corrosive media and/or at high temperatures requires improved characteristics of the performance and durability of filtering equipment. The Ti – Al intermetallic system combines low density with high strength and exhibits high resistance to oxidation and corrosion at elevated temperatures. We present the results of studying high-temperature Ti – Al cermet products (filters) with nanoscale pores. Filters were obtained from a mixture of Ti and Al powders (mass ratio 40:60) by thermal explosion. XRD methods showed that the synthesized material consists of two main phases: TiAl3 and Al2O3. The microstructure analysis revealed the presence of large-sized TiAl3 structures and spherical Al2O3 aggregates enveloped by nanostructured TiAl3. Moreover, nanoscale fibrous TiAl3 compounds forming a multilevel developed cobweb-like structure are observed in the entire volume of the pore space of the material. The open porosity of the material was 48%, the pore size was 0.1 – 0.2 μm, the efficiency of the porous material was 99.999%, the resistance to gas flow was 100 mm of water column, and the filtration index was 0.062. Thermal tests revealed the possibility of effective use of filters under conditions of elevated (up to 800°C) temperatures and corrosive media due to the chemically stable and heat-resistant binary structure of the material. The results obtained can be used to improve the methodology of the development and operation of high-temperature cermet filters based on Ti – Al.