34 research outputs found
Opportunities for the use of the small-size accelerator VGIK-1
The experimental data on modification of the surface of metals, alloys and materials coated using the method of irradiation by a heavy-current electron beam with the energy of 300 keV have been given. The specimen surface structure was studied before and after the irradiation using the method of optic microscopy and the surface layer microhardness measurement. The method of electron microscopy was used to analyze the structure and the sizes of dispersed anode material. The films consisting of the crystals with the size of 6 to 8 nm were obtained. The mass transfer processes that occur in the material of metal targets made of Cu, Ti, Mo, Al were studied. The spatial map was compiled for the X-ray field of the plant. The experiments were carried out to define the action of X-ray radiation on the different types of conditionally pathogenic microflora, in particular such bacteria as Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. The fields of application of the plant were defined.Представлено експериментальні результати по модифікації поверхні металів, сплавів і матеріалів з нанесеними покриттями методом опромінення потужнострумовим електронним пучком з енергією до 300 кеВ. Вивчена структура поверхні зразків до і після опромінення методом оптичної мікроскопії та вимірювання мікротвердості в поверхневому шарі. Методом електронної мікроскопії проведено аналіз структури і розмірів розпорошуваного матеріалу анода. Отримано плівки, що складаються з кристалів розміром 6…8 нм. Досліджено процеси масопереносу матеріалу металевих мішеней Cu, Ti, Mo, Al. Складено об'ємну карту рентгенівського поля установки. Проведено експерименти з впливу рентгенівського випромінювання на різні типи умовно патогенної мікрофлори: бактерії типу Escherichia coli, Staphylococcus aureus, Bacillus subtilis. Визначено подальші напрямки застосування установки.Представлены экспериментальные результаты по модифицированию поверхности металлов, сплавов и материалов с нанесенными покрытиями методом облучения сильноточным электронным пучком с энергией до 300 кэВ. Изучены структура поверхности образцов до и после облучения методом оптической микроскопии и измерения микротвердости в поверхностном слое. Методом электронной микроскопии проведен анализ структуры и размеров распыляемого материала анода. Получены пленки, состоящие из кристаллов с размером 6…8 нм. Исследованы процессы массопереноса материала металлических мишеней Cu, Ti, Mo, Al. Составлена объемная карта рентгеновского поля установки. Проведены эксперименты по воздействию рентгеновского излучения на различные типы условно патогенной микрофлоры: бактерии типа Escherichia coli, Staphylococcus aureus, Bacillus subtilis. Определены дальнейшие направления применения установки
Experimental results of microprobe focusing by quadruplet with four independent lens power supplies
Application of Electron Beam for Wastewater Disinfection
AbstractThe objective of the study is to consider the possibility of applying the nanosecond electron beam for disinfecting wastewater. The advantages of this method have been illustrated. The mechanism of influence of ionizing radiation on cells has been described. The microbial suspension has been irradiated with the electron accelerator, and then the effectiveness of the electron beam as a disinfecting agent has been assessed. In most cases there has been a bactericidal effect, while in some cases a bacteriostatic effect has been observed. On the example of E. coli culture, it has been shown that the nanosecond electron beam is an effective disinfecting agent for the of wastewater treatment
Realization of narrow-band SC-filters with low power consumption
Synthesis of a narrow band switched-capacitor (SC) filter is discussed. Design is based on element simulation method when inductors of the filter prototype have been realized by 4-phase controlled single OpA SC-imitator that gives a possibility to decrease power consumption of the device. A six order Chebyshev type bandpass SC-filter with a middle frequency 1980 Hz and a frequency band 200 Hz has been synthesized and practically implemented in 0.35 um CMOS process. The input referred RMS noise is 140 uV while HD2 and HD3 are -45, -53 dB consequently when the input signal amplitude is equal to about 90 mV. The total current consumption of the filter is 420 uA with 3.3 V voltage supply. The active area of the filter is 800 um x 500 um
IMPACT OF BETALACTOGLOBULIN HYDROLYSATE ON STRUCTURAL AND MECHANICAL PROPERTIES OF ALLERGENIC POTENCY-RESTRICTED YOGURT
Creation and development of low-allergenic food products in sour-milk drink groups is the urgent trend in dairy industry development. By the results of patent search, one of challenging methods to reduce the dairy product allergenicity has been identified. To produce such products, the method involves using whey protein hydrolysates, in particular, β-lactoglobulin hydrolysate obtained by using enzyme preparations Flavorpro 750MDP and Promod 439L. The research aimed to study normalized milk mixtures fermented with β-lactoglobulin hydrolysate with the resulting changes in the chemical composition, as well as to select starter microorganisms that provide the required stability and structure of the milk coagulum by producing exopolysaccharides. The researches were carried out at the base of several laboratories as follow: The Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences, Christian Hansen LLC, the Voronezh State University of Engineering Technologies and the Federal Research Centre of Nutrition and Biotechnology. This work is based on standard and conventional research methods. Advanced tools and information technologies were used to assess the properties of raw materials, semi-finished products and food products. By the results of studies completed, it was found unreasonable to replace over 20% of whole milk with β-lactoglobulin hydrolysate during normalization, since such replacement resulted in an increase in the mixture acidity and prevented the normal growth and development of Streptococcus thermophilus, the basic exopolysaccharide producer. At the same time, the length of fermentation increased up to 5-6 h as the mass fraction of β-lactoglobulin hydrolysate increased. The viscosity of the resulting coagulum increased due to the reaction of exopolysaccharides with the protein gel mesh and fixation thereof on the surface of protein matrix. The residual antigenicity of the finished product decreased to 48.5% relative to that of sour-milk drinks produced as per traditional technology
Radiocarbon Dates of Late Quaternary Mammals in the Archangelsk Region and Their Contribution to Reconstructions of the Last Glaciation in Eastern Europe
Twelve new AMS (Accelerator Mass Spectrometry) dates of large Quaternary mammal remains were reported: mammoth (Mammuthus primigenius), bison (Bison priscus), and musk ox (Ovibos pallantis) found in the Archangelsk Region. The absolute age of the identified samples varies from 46 000 to 22 000 calibrated years ago. These data suggest that a substantial part of the Archangelsk Region was not covered by ice during the indicated time interval.
Late Holocene small mammals from localities of Sharyu River Valley (Chernyshev's Ridge)
Bioarchaeolog
The History of Formation of Recent Small Mammal Communities in the Nether-Polar Urals
The results of studies on small mammal bone assemblages from seven cave-type sites on the Shchugor and Kozhim rivers are presented. Four stages in the development of small mammal fauna in the Nether-Polar Urals are described, which correspond to the Alleröd, Younger Dryas, Early Holocene, and Subatlantic periods. The moderately cryohydrophilic fauna of the Alleröd was replaced by an atypically “mild” xerophylic community in the Younger Dryas. In the Early Holocene, its structure still included considerable proportions of tundra species, which, along with forest species, were also found in the subfossil assemblage from the Subatlantic. It is shown that the transformation of the small mammal fauna in the above sites had a specific pattern, compared to that in other regions of northeastern Europe and to the dynamics of the natural environment and climate.
New data on changes in the European distribution of the mammoth and the woolly rhinoceros during the second half of the Late Pleistocene and the early Holocene
The PALEOFAUNA database developed by the authors contains information on more than 5500 Eurasian localities that yielded Late Pleistocene and Holocene mammalian fossils. The database is used to analyze the changes in the geographical distribution during the second half of the Late Pleistocene and the Holocene of two significant species – the mammoth Mammuthus primigenius and the woolly rhinoceros Coelodonta antiquitatis. Based on the geographical information, combined with (new) radiocarbon data, a correlation has been established between the observed shifts in the ranges of the two species and the climatic changes that occurred during the past 50 000 years. The results indicate that both species changed their distribution repeatedly; the expansion of the ranges increased during stadial intervals and decreased during most interstadials. Both species reached their maximum expansion during the Denekamp (=Bryansk) Interstadial, a relatively long interval that includes a number of cold phases. Later, the ranges in Europe of both mammoth and rhinoceros were reduced, a process that started before the end of the LGM. Progressive warming from the end of the Pleistocene onwards resulted in dramatic changes in the environment that appeared to be critical for the distribution of those animals. Mammoth and woolly rhinoceros ranges disintegrated into isolated spots, and later they disappeared completely from Eurasia. Relict populations of small mammoths persisted longer on isolated islands such as Wrangel Island. However, not only climate change had an impact on the distribution of the two species. Late Paleolithic and Mesolithic hunters might also have affected the size of the mammoth and woolly rhinoceros populations. Their impact was probably particularly high when the species were close to extinction.