Специальные подборки
Издания подборки 21 - 30 из 1777
21.

Количество страниц: 8 с.

The process of the paraffin type asphaltene-resin-paraffin deposits dissolution in the alkane base gas condensate, hexane-benzene mixture (HBM) and hexane at 10 and 25°C is investigated. These deposits are formed during oil production in the Irelyakh field. The comparative effectiveness evaluation of studied solvents is performed by the widely used in practice "baskets" method and the results of kinetic studies.

Ivanova, I. K. Use of a kinetic study for the effectiveness evaluation of asphaltene-resin-paraffin deposits (ARPD) solvents / I. K. Ivanova, E. Yu. Shitz // Нефтегазовое дело. - 2012, N 3. - С. 353-359.

22.

Количество страниц: 10 с.

Peculiarities of the distribution of high-molecular normal alkylbenzenes in the Vendian-Cambrian oils of the Siberian platform are studied according to the data of chromatomass-spectrometry. The predominance of high-molecular homologues with the odd number of carbon atoms in a molecule is established. The possible biochemical precursors and the probable mechanism of the formation of “odd” monoalkylbenzenes are suggested.

Ivanova, I. K. Monoalkylbenzenes in oils of the Vendian-Cambrian deposits / I. K. Ivanova // Нефтегазовое дело. - 2008, N 1. - С. 23.

23.

Количество страниц: 6 с.

This paper uses the plasma data from Cluster and TC-1 and geomagnetic data to study the geomagnetic signatures of current wedge produced by fast-flow braking in the plasma sheet. The three fast flows studied here occurred in a very quiet background and were accompanied by no (or weak) particle injections, thus avoiding the influences from other disturbances. All the geomagnetic signatures of a substorm current wedge can be found in geomagnetic signatures of a current system produced by the braking of fast flows, indicating that the fast flows can produce a complete current wedge which contains postmidnight downward and premidnight upward field-aligned currents, as well as a westward electrojet. The Pi2 precursors exist not only at high latitudes but also at midlatitudes. The starting times of midlatitude Pi2 precursors can be identified more precisely than those of high-latitude Pi2 precursors, providing a possible method to determine the starting time of fast flows in their source regions. The AL drop that a bursty bulk flow produces is proportional to its velocity and duration. In three cases, the AL drops are 200 nT, whether a substorm can be triggered depends mainly on the conditions of the braking regions before fast flows. The observations of solar wind before the three fast flows suggest that it is difficult for the fast flows to trigger a substorm when the interplanetary magnetic field Bz of solar wind is weakly southward.

Geomagnetic signatures of current wedge produced by fast flows in a plasma sheet / Jin-Bin Cao, Chunxiao Yan, Malcolm Dunlop, Henri Reme, Iannis Dandouras, Tielong Zhang, Dongmei Yang, Alexey Moiseyev, Stepan I. Solovyev, Z. Q. Wang, A. Leonoviche, N. Zolotukhina, and V. Mishin // Journal of Geophysical Research: Space Physics. – 1978. – 2010 (August), vol. 115, N 8. – P. A08205.

24.

Количество страниц: 4 с.

Long-lasting ground based measurements of a polarization jet (PJ) by the latitudinal chain of ionospheric stations in Yakutia (3 < L < 5; MLT = UT + 9 h) and by 5 subauroral Russian stations were analyzed. A number of cases were found when PJ was recorded simultaneously with energetic ion observations by AMPTE/CCE and INTERBALL 2. The data comparison shows that at least in the considered cases of strong magnetic substorms, PJ was accompanied by strong injection of ions with the energy of ~20-50 keV and intensity of ~10 cm-² c-¹ sr-¹keV-¹. Close to the injection region in the near midnight sector no ion dispersion was observed, but in the evening sector nose events were detected. In accordance with the mechanism suggested by Southwood and Wolf (JGR, 1978, 83, 5227) PJ was observed near the equatorial boundary of energetic ion penetration into the magnetosphere. Measurements by ionosonds at different longitudes show that the westward velocity of the frontt of PJ development is close to the gradient drift velocity of 20 keV ions (forming nose events). Thus, the physical mechanism of PJ formation due to energetic ion injection during a strong substorm burst is experimentally confirmed. Satellite measurements show that in the near midnight sector energetic ions reach the shell L=3.0 in 20-30 minutes after a substorm commencement with AE>500 nT.

Formation of polarization jet during injection of ions into the inner magnetosphere / V. L. Khalipov, Yu. I. Galperin, A. E. Stepanov, E. D. Bondar // Physics of auroral phenomena : proceedings of the 25th annual seminar, Apatity, 26 February – 1 March 2002. – 2002. – P. 43-46.
DOI: 10.1016/S0273-1177(03)00016-4

25.

Количество страниц: 4 с.

Обобщены сведения о современном составе фауны пауков (Araneae) Якутии. Приведены виды из статей по Якутии, опубликованных после обобщающего списка видов [Marusik et al., 1993], а также некоторые номенклатурные изменения. В настоящее время фауна пауков насчитывает 446 видов из 20 семейств; за последние 20 лет 22 вида представлены как новые для региона, пять из них - новые для науки. В северной Якутии для некоторых видов были указаны самые северные точки распространения.

Koponen, S. Current knowledge of spider fauna (Araneae) of Yakutia / S. Koponen, N. K. Potapova, A. P. Burnasheva // Евразиатский энтомологический журнал. – 2014, Т. 13, N 5. – С. 430-433.

26.

Издательство: [s. n.]

Год выпуска: 1988

Количество страниц: 14 с.

The influence of continious CO2-laser processing on structure, composition and microhadness of plasma sprayed Ni-Cr-Si-B, Fe-C-Cr-V, Ni-Al coatings was studied. The change of chemical and phase compositions of the coatings compared with the initial sprayed ones due to alloying with elements of substrate, depending on the processing operation (input power) was determined. Laser processing of plasma sprayed coatings allows to improve substantially their adhesion and in combination with high speed cooling, gives the possibility to regulate the processes of structure formation, dispersion, phase formation, and hence, the properties of forming coatings by means of processing operation.

Laser processing of plasma sprayed coatings / Dr. V. P. Larionov, Cand. N. P. Bolotina, Eng. T. V. Argunova, Cand. V. D. Tyunin, Eng. M. P. Lebedev. — [S. l. : s. n.], 1988. — 6 c.

27.

Количество страниц: 14 с.

Lazarev, N. P. Equilibrium problems for Kirchhoff–Love plates with nonpenetration conditions for known configurations of crack edges / N. P. Lazarev, H. Itou // Математические заметки СВФУ. — 2020. — Т. 27, N 3 (107), июль-сентябрь. — С. 52-65
DOI: 10.25587/SVFU.2020.75.68.005

28.
Автор:

Количество страниц: 5 с.

Климат в Якутии характеризуется низкими зимними и высокими летними температурами, что является причиной высокой степени сухости воздуха, достигающей 30 % в отдельные периоды. Поэтому насекомые, обитающие в таких условиях, выработали в процессе эволюции определенные механизмы адаптации. В данном исследовании оценка водного баланса для нескольких морозотолерантных видов (Aporia crataegi L., Upis ceramboides L., Pieris rapae L., Delia floralis Fallen, личинки, принадлежащие Diptera) была основана на измерении скорости потери воды, скорости метаболизма и содержания воды в организме. В соответствии с полученными данными, Upis ceramboides, Pieris rapae, Delia floralis, личинки, принадлежащие к Dipera, характеризуются высокой проницаемостью клеточной стенки тела. Это связано с тем, что биологический цикл развития этих видов сопровождается низкой степенью экспозиции по отношению к сухому воздуху. Для них замерзание клеточной жидкости, инициированное лёд-нуклеирующими белками, вероятно, является существенной частью водосохраняющего механизма в зимний период. В противоположность этим видам, гусеницы Aporia crataegi L. обитают в условиях высокой степени экспозиции к сухому воздуху и поэтому имеют низкую кутикулярную водопроницаемость, сравнимую с таковой для африканских жуков. Этот механизм позволяет данному виду сохранять до 70 % воды в организме, несмотря на экстремально низкую влажность воздуха в окружающей их среде. В соответствии с данным исследованием, другой механизм поддержания водного баланса в зимний период, связанный с продукцией лёд-нуклеирующих белков, не является существенным для данного вида. Наконец, кокон, в котором гусеницы находятся с осени, всю зиму и весной, также защищают их от дегидратации в "сухие" сезоны года.

Li, N. G. Water balance of freeze-tolerant insect larvae inhabiting arid areas in Eastern Siberia (Yakutia, Russia) / N. G. Li // Евразиатский энтомологический журнал. – 2015, Т. 14, N 1. – С. 37-41.

29.

Количество страниц: 4 с.

The geomagnetic manifestation of sudden impulse (SI) caused by a sharp decrease of the solar wind dynamic pressure due to the plasma density reduction is considered. The observational data of the magnetometer world network have been analysed. The propagation velocities of the SI signal in the meridional direction by using data of the horizontal component of geomagnetic field in the high-latitude region have been calculated. It is found that at a sharp decrease of the solar wind density the meridional propagation of the SI signal is in the northern direction. In this case, on the day side the propagation velocity is constant but there is a tendency of its increasing in the MLT morning sector. It has been established that the meridional propagation velocity of the SI signal at a sharp decrease of the solar wind density depends on the geomagnetic latitude, i.e. with the rise of latitude the velocity in the auroral zone decreases and in the polar cap it increases.

High-latitude peculiarities of the geomagnetic SI impulse propagation meridional velocity during sharp decrease of solar wind density / G. A. Makarov, D. G. Baishev, A. V. Moiseyev, S. I. Solovyev, V. A. Pilipenko, M. J. Engebretson, K. Yumoto // Proceedings of the Fifth International Conference on Substorms : 16-20 May 2000 Congress Centre of the Arctic and Antarctic Research Institute, St. Petersburg, Russia. − Noordwijk, Netherlands : European Space Agency, 2000. − P. 523-526.

30.

Количество страниц: 1 с.

Makarov, G. A. Propagation velocities of geomagnetic sudden impulses caused by sharp changes jf solar wind dinamic pressure at high latitudes / G. A. Makarov, V. Moiseev, and S. I. Solovyev // The First S-Ramp Conference, October 2-6, 2000: Sapporo, Japan. – Sapporo, 2000. – P. 122.