74 research outputs found

    Estimating the contribution from different ionospheric regions to the TEC response to the solar flares using data from the international GPS network

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    This paper proposes a new method for estimating the contribution from different ionospheric regions to the response of total electron content variations to the solar flare which uses the effect of partial shadowing of the atmosphere by the terrestrial globe. The study uses GPS stations located near the boundary of the shadow on the ground in the nightside hemisphere. The beams between the satellite-borne transmitter and the receiver on the ground for these stations pass partially through the atmosphere lying in the region of total shadow and partially through the illuminated atmosphere. The analysis of the ionospheric effect of a powerful solar flare of class X5.7/3B that was recorded on July 14, 2000 (10:24 UT, N22W07) in quiet geomagnetic conditions (Dst=-10 nT) has shown that about 20% of the TEC increase correspond to the ionospheric region lying below 100 km, about 5% refer to the ionospheric E-region (100-140 km), about 30% correspond to the F1-region (140-200 km), and about 30% to regions lying above 300 km.Comment: LaTeX, 6 pages, 4 figures, 1 tabl

    The response of the ionosphere to faint and bright solar flares as deduced from global GPS network data

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    Results derived from analysing the ionosphere response to faint and bright solar flares are presented. The analysis used technology of a global detection of ionospheric effects from solar flares as developed by the authors, on the basis of phase measurements of the Total Electron Content (TEC) in the ionosphere using an international GPS network. The essence of the method is that use is made of appropriate filtering and a coherent processing of variations in the TEC which is determined from GPS data, simultaneously for the entire set of visible GPS satellites at all stations used in the analysis. This technique is useful for identifying the ionospheric response to faint solar flares (of X-ray class C) when the variation amplitude of the TEC response to separate line-on-sight to GPS satellite is comparable to the level of background fluctuations. The dependence of the TEC variation response amplitude on the bright flares location on the Sun is investigate

    GPS detection of the instantaneous response of the global ionosphere to strong magnetic storms with sudden commencement

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    Using a new technology for global GPS detection of ionospheric disturbances, GLOBDET, it has been established that a drastic increase in the time derivative of the magnetic field strength during magnetic storms is accompanied by an almost simultaneous decrease in mid-latitude total electron content on the entire dayside. The corresponding correlation coefficient is not below -0.8; the delay with respect to the time of a magnetic storm sudden commencement is about 3-10 min. This is most pronounced for magnetic storms with a well-marked sudden storm commencement. The sudden storm commencements presented in the paper were observed during the initial storm phase. The analysis reported here was made for a set of from 90 to 300 GPS stations for 10 days in 1998-2001 with a different level of geomagnetic activity (Dst from -6 nT to -295 nT, and K p from 0 to 9). The «simultaneous» total electron content response for the events under consideration was 0.1-0.4 TECU, and the travel velocity of the disturbance from the dayside to the nightside was in the order of 10-20 km/s. Results obtained are consistent with earlier ionospheric parameter measurements obtained using high temporal resolution methods

    Metabolic syndrome and pancreatic lesions

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    Aim of investigation. To study features of pancreatic involvement in patients with metabolic syndromeMaterial and methods. Overall 720 patients were investigated who have admitted to the clinic with referral diagnosis «chronic pancreatitis» (CP). Of them steatosis of pancreas (SP) was diagnosed in 49 and in 290 – chronic pancreatitis. Original investigation algorithm was based on tasks of the study and included careful inquiry and physical investigation of patients. Laboratory and instrumental studies included: total and biochemical blood tests, lipid profile, coprological test, transabdominal and (under specific indications) endoscopic abdominal US, esophagogastroduodenoscopy (EGDS), computer tomography (CT) of abdominal organs, magnetic-resonance investigation (MRI).Results. According to diagnostic criteria of metabolic syndrome, the latter was detected in 48 patients. Abdominal CT was considered as non-invasive method of investigation allowing to reliably diagnose SP. At CT in 49 cases SP was revealed. Direct CT signs of SP include decrease in pancreatic density score (<30 HU), lobulated pattern of the gland with pronounced fatty layers. Diagnosis of chronic pancreatitis was made according to conventional clinical, laboratory and radiological criteria. The metabolic syndrome was significantly more frequent (р<0,05) in patients with SP, than at chronic inflammatory pancreatitis: in 29 of 49 cases (59,2%) and in 29 of 147 cases (19,7%) respectively. The issue of application of new phospholipid drug Resalut in patients with SP, associated to hepatic steatosis and lipidemia is discussed. Conclusion. Steatosis of the pancreas can be considered as diffuse development of fatty tissue in all parts of the organ, developing mainly on the background of metabolic syndrome and combined to smoldering pancreatic inflammation under influence of pancreatoxic factors – alcohol, gallstone disease. Efficacy of new phospholipid drug Resalut in patients with steatosis of the pancreas associated to hepatic steatosis and lipidemia is demonstrated

    ОСОБЕННОСТИ ПОЛУЧЕНИЯ ЩЕЛОЧНО-СИЛИКАТНЫХ ТЕПЛОИЗОЛЯЦИОННЫХ МАТЕРИАЛОВ

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    The paper presents investigation results pertaining to peculiar features of thermal insulation material production and description of their property study. The production process presupposes  swelling of alkaline-silicate raw materials at temperature 300–500 °C of mixes, are presented. Представлены результаты исследований особенностей получения теплоизоляционных материалов, создаваемых вспучиванием при температуре 300–500 °С щелочно-силикатных сырьевых смесей, и изучения их свойств

    ФИЗИКО-ХИМИЧЕСКИЕ ОСНОВЫ ТЕХНОЛОГИИ РЕМОНТА ЖЕЛЕЗОБЕТОННЫХ КОНСТРУКЦИЙ

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    The paper presents a brief review of new methods for repair of concrete and reinforced concrete products, structures etc. The review demonstrates that the usage of diffusion processes proceeding in the porous materials makes it possible to obtain positive effects while performing  repair works. Представлен краткий обзор новых подходов к ремонту бетонных и железобетонных изделий, конструкций и т. д., из которого следует, что использование диффузионных процессов, протекающих в пористых материалах, позволяет достичь положительных эффектов при проведении ремонтных рабо

    ОСНОВНЫЕ МОДИФИКАЦИИ РАСТВОРОБЕТОННЫХ УЗЛОВ БЛОЧНО-МОДУЛЬНОЙ КОМПОНОВКИ

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    The paper considers a new BNTU development that is concrete complexes having modular-block design. The modular-block approach presupposes to divide the whole technological chain for production of concrete and mortar mixes into separate sections (modules), each of which performs specific functions and can be used separately and independently of others. Then it is necessary to select such set of modules that ensure production of concrete and mortars. The paper presents designs of main modules in the technological chain for preparation of concrete mixes: a concrete mixing module, a storage and supply module of inert materials, a storage and supply module of cement and a number of additional auxiliary modules (a concrete supply module, a module for preparation of chemical additives, an operator module and a module for preparation and supply of air).Two main modifications of ready mix concrete stations developed on the basis of modular-block principle using basic modules are given in the paper. The first modification is a stationary concrete-mortar complex characterized by high productivity, large reserves of aggregates and cement, ability to be operated in winter due to heat insulation and water heating system and inert materials. The second modification is a transportable option that permits to transport the station from place to place due to reduction of time required for its installation and removal and execute production of concrete mixtures in the vicinity of the object construction. This options provides the possibility to reduce expenses on concrete transportation to the place of its deposit and decrease the probability of deterioration of consumer properties of the concrete mix that in its turn entails reduction in final cost of the object construction and improves quality of the construction.Рассмотрена новая разработка БНТУ – растворобетонные комплексы блочно-модульной конструкции. Блочномодульный принцип состоит в том, чтобы разбить всю технологическую цепочку по производству бетонных и растворных смесей на отдельные участки (модули), каждый из которых выполняет отдельные функции и может использоваться независимо от других. Далее набирают комплект таких модулей для обеспечения производства бетонов и растворов. Представлены конструкции основных модулей технологической цепочки по приготовлению бетонных смесей: бетоносмесительный модуль, модуль хранения и подачи инертных материалов, модуль хранения и подачи цемента, а также ряд дополнительных вспомогательных модулей (подачи бетона, приготовления химических добавок, операторской, подготовки и подачи воздуха).Приведены две основные модификации растворобетонных узлов, разработанных по блочно-модульному принципу с использованием основных модулей. Одна является стационарным вариантом растворобетонного комплекса, обладающего высокой производительностью, значительными запасами инертных материалов и цемента, возможностью работы в зимний период за счет утепления и системы подогрева воды и инертных материалов. Вторая – это перебазируемый вариант, позволяющий перевозить установку с места на место за счет сокращения времени монтажа и демонтажа и наладить производство бетонных смесей в непосредственной близости к объекту строительства. Это дает возможность сократить расходы на транспортирование бетона к месту укладки, а также уменьшить вероятность ухудшения потребительских свойств бетонной смеси, что в свою очередь снижает окончательную стоимость и повышает качество объекта строительства
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