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Application of Coulometric Titration for the Certification of Primary Reference Materials of Pure Substances

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American Journal of Analytical Chemistry 2014年第9期5卷 559-565页

作者： gennady I. Terentiev Alena v. Sobina Alexandr J. Shimolin veniamin M. Zyskin Ural Scientific and Research Institute for Metrology Ekaterinburg Russia

In this article, the block scheme and metrological characteristics of the State primary standard of the mass (molar) fraction and mass (molar) concentration of the component in the liquid and solid substances and materials based on coulometric titration GET 176-2010 are given. Primary reference materials certified by coulometric titration in the Ural Scientific and Research Institute for Metrology include eight certified reference materials (CRMs) of pure solid substances (mostly salts of sodium or potassium) and one hydrochloric acid solution CRM. The metrological characteristics of these reference materials and the scheme of their application in titrimetric analysis are shown. The expanded uncertainty of the certified value (mass fraction for the solid substances or molar concentration for the solution) is in the range from 0.018% to 0.05%. Information about two primary reference materials of high purity iron and lead nitrate certified by controlled-potential coulometry with expanded uncertainty from 0.04% to 0.07% is also given.

关键词： Coulometric Titration Controlled-Potential Coulometry Primary Reference Materials High Purity Substances State Primary Standard

Influence of Cathode Plasma on Breakdown Formation in Plasma-Anode Explosive-Emission Source

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Journal of Energy and Power Engineering 2012年第6期6卷 999-1004页

作者： Eduard N. Abdullin gennady P. Bazhenov Yury P. Bazhenov Alexander v. Morozov Microwave Electronics Laboratory Institute of High Current Electronics SB RAS Tomsk 634055 Russia

Breakdown formation in an explosive-emission electron source is related to the interelectrode gap filling with plasma propagating from the cathode and formed at the anode and in the interelectrode gap under the electron beam action. Plasma anode is used to increase the beam current density. Preliminary interelectrode gap filling with plasma in the explosive-emission source decreases the influence of uncontrolled plasma arrival from the anode on the diode processes, promotes current density increase and duration of generated electron beams. The paper considers the influence of the cathode geometry on the breakdown formation in the plasma-anode explosive-emission electron source. The data on obtaining of microsecond electron beams with current density of 30 A/cm^2 and 1.5-2 kA/cm^2 are presented.

关键词： Explosive-emission electron source plasma anode high-current phase of vacuum discharge.

Glucose transporters expression in the placental terminal villi of preeclampsia and intrauterine growth retardation complicated pregnancies

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Health 2013年第7期5卷 100-104页

作者： Elena A. Dubova Konstantin A. Pavlov Galina v. Kulikova Alexander I. Shchegolev gennady T. Sukhikh Department of Pathology Research Center for Obstetrics Gynecology and Perinatology Moscow Russia

Introduction: Transmembrane sodium-independent glucose transporters (GLUTs) play an important role in both placental and fetal development by the providing transplacental glucose transport. Abnormal GLUT-1 and GLUT-3 placental expression could play a role in such late pregnancy complications development as preeclampsia and intrauterine growth retardation. Materials and Methods: Immunohistochemistry was performed to reveal patterns of GLUT-1 and GLUT-3 expression in the placental terminal villi compartments. Results: GLUT-1 syncytial expression in the terminal villi of severe PE cases (both with and without IUGR) was significantly lower in compare to control group. We also report about GLUT-3 both syncytial and endothelial expression in the near term and term placental terminal villi without significant difference between the study and control groups. Conclusion: other study should be performed to establish the nature of GLUT-1 downregulation in severe preeclampsia cases and whether GLUT-3 is expressed in the syncytiotrophoblast of near term and term placentas or not.

关键词： Preeclampsia Placenta GLUT-1 GLUT-3

variations of vLF radio signals and atmospherics during the deep earthquake with M = 8.2 occurred on 24 May 2013 near Kamchatka peninsula

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Natural Science 2014年第3期6卷 144-149页

作者： viktor A. Mullayarov gennady I. Druzhin vyacheslav v. Argunov Larisa M. Abzaletdinova Aleksander N. Mel’nikov Institute of Cosmophysical Research and Radiowaves Propagation FEB of RAS Paratunka Russia Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy SB of RAS Yakutsk Russia

To detect seismic disturbances in the lower ionosphere, we have used the signals of very-lowfrequency radio transmitters and natural radio signals—electromagnetic emission of lightning discharges—atmospherics. On earlier results of observation of atmospherics, it was obtained that the earthquake effects are displayed as weight-hourly amplitude increases on the day of event or within 3 days after them. Possible earthquake precursors are also manifested as one-day (within one to several hours) increases in the amplitude of atmospherics on average 5 - 12 days before the event. Analysis shows that seismic effects in the amplitude of atmospherics have been observed in the case of sufficiently strong (magnitude M > 4.5) and not very deep (usually no deeper than 50 km) earthquakes. The effects of the events of the earthquake with magnitude of 8.2 occurring in the Sea of Okhotsk on 24.05.13 not far from the Kamchatka Peninsula at a depth of 609 km considered in this work have shown that even deep earthquakes may have precursors in the form of disturbances in the lower ionosphere.

关键词： Earthquake Precursor Ionosphere Atmospherics Radio Signals

Structure and Thermoelectric Properties of Nanostructured (Bi, Sb)2Te3(Review)

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Advances in Materials Physics and Chemistry 2013年第2期3卷 119-132页

作者： Igor A. Drabkin vladimir v. Karataev vladimir B. Osvenski Aleksandr I. Sorokin gennady I. Pivovarov Natalie Yu. Tabachkova Department of dielectric and semiconductor materials National University of Science and Technology “MISIS” Moscow Russia Department of functional and structural materials Technological Institute of Superhard and New Carbon Materials Troitsk Russia Department of semiconductor materials Giredmet Ltd. Moscow Russia

The investigation of the structure and thermoelectric properties of nanostructured solid solutions (Bi, Sb)2Te3 p-type has been carried out. The samples were obtained by grinding of original compositions in a planetary ball mill and by spark plasma sintering (SPS). Initial powder has an average particle size of 10 - 12 nm according to transmission electron microscopy, and the size of the coherent scattering region (CSR) obtained by X-ray line broadening. During sintering at Ts = 250°C - 400°C, the grain size and CSR increased, which was associated with the processes of recrystallization. The maximum of size distribution of CSR shifts to larger sizes when Ts increases so that no broadening of X-ray lines at Ts = 400°C can take place. At higher Ts, the emergence of new nanograins is observed. The formation of nanograins is conditioned by reducing of quantity of the intrinsic point defects produced in the grinding of the source materials. The study of the electrical conductivity and the Hall effect in a single crystal allows to estimate the mean free path of the holes-L in the single crystal Bi0.5Sb1.5Te3 which at room temperature is 2 - 5 nm (it is much smaller than the dimensions of CSR in the samples). The method for evaluation of L in polycrystalline samples is proposed. At room temperature, L is close to the mean free path in single crystals. Scattering parameter holes in SPS samples obtained from the temperature dependence of the Seebeck coefficient are within the measurement error equal to the parameter of the scattering of holes in a single crystal. The figure of merit ZT of SPS samples as a function of composition and sintering temperature has been investigated. Maximum ZT, equal to 1.05 at room temperature, is obtained for the composition Bi0.4Sb1.6Te3 at Ts = 500°C and a pressure of 50 MPa. The causes of an apparent increase in thermoelectric efficiency are discussed.

关键词： Solid Solutions (Bi Sb)2Te3 P-Type Nanostructure Spark Plasma Sintering Conductivity Hall Effect Hole Free Path Seebeck Coefficient Thermal Conductivity Figure of Merit

Spontaneous Changes of Solid 5,7-di-tert-butylspiro(2,5)octa-4,7-diene-6-one in Storage Conditions at Room Temperature

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Advances in Chemical Engineering and Science 2015年第3期5卷 299-304页

作者： Alexandre A. volodkin gennady E. Zaikov Lydia N. Kurkovskaja Sergey M. Lomakin Irina M. Levina Elena v. Koverzanova Federal State Budgetary Establishment of a Science of Institute of Biochemical Physics of N. M. Emanuelja of Russian Academy of Sciences Moscow Russia Federal State Budgetary Establishment of a Science of Institute of Chemical Physics of N. N. Semenov of Russian Academy of Sciences Moscow Russia

On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-butyl-4'-hydroxy-phenyl)-ethyloxy-p-cresole is produced as result of a structure transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one in a solid phase at room temperature except a single crystal at transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one a new substance is formed too. Spectrums 1Н and 13С NMR differ from similar spectrums of initial compound and the single crystal. New substance represents an admixture of isomeric compounds, capable reversible to be transformed in initial 5,7-di-tert-butylspiro(2,5) octa-4,7-diene-6-one and 2-(3’, 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole.

关键词： Solid-Phase Reactions 5 7-Di-tert-butylspiro(2 5)octa-4 7-diene-6-one 2-(3’ 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole NMR and IR Spectroscopy

Multipotent stromal cells stimulate liver regeneration by influencing the macrophage polarization in rat

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World Journal of Hepatology 2018年第2期10卷 287-296页

作者： Andrey Elchaninov Timur Fatkhudinov Natalia Usman Irina Arutyunyan Andrey Makarov Anastasia Lokhonina Irina Eremina viktor Surovtsev Dmitry Goldshtein Galina Bolshakova valeria Glinkina gennady Sukhikh National Medical Research Center for Obstetrics Gynecology and Perinatology named after Academician V.I.Kulakov of Ministry of Healthcare of Russian FederationMoscow 117997Russia Peoples Friendship University of Russia(RUDN University) Moscow 117198Russia Scientific Research Institute of Human Morphology Moscow 117418Russia Pirogov Russian National Research Medical University Ministry of Healthcare of the Russian FederationMoscow 117997Russia Research Center of Medical Genetics Moscow 115478Russia

AIM To investigate the influence of the umbilical cordderived multipotent stromal cells(MSCs) on recovery of the liver after the subtotal resection, that is, removal of 80% of the organ mass, a renowned model of the small-for-size liver remnant syndrome. METHODS The MSCs were obtained from the intervascular tissue of umbilical cords, dissected from rat fetuses, by the explant culture technique. The vital labeling of MSCs with РКН26 was carried out on the 3 rd passage. The subtotal resection was performed on male Sprague-Dawley rats. The experimental group animals received a transplant 106 MSCs infused into the spleen. Hepatocyte proliferation was assessed by counting of either mitotic figures or Ki67-positive cells in microscopic images. MSC differentiation was assessed with antibodies to hepatocyte-specific marker cytokeratin 18(CK18), cholangiocyte-specific protein CK19, smooth muscle cell-specific protein α-SMA, the endothelial cell marker CD31, or the active fibroblast marker FAPα. Total macrophages of the liver were selectively stained in cryosections incubated with antiCD68 antibodies(1:100, Abcam), while the M2 a and M2 c macrophage populations were selectively stained with anti-CD206 antibodies. Expression of interleukin and growth factor genes was evaluated with *** Intrasplenic allogeneic transplantation of the umbilical cord-derived multipotent stromal cells stimulates reparative processes within the residual liver tissue after subtotal resection(removal of 80% of the organ mass), as indicated by increased rates of hepatocyte proliferation and accelerated organ mass recovery. These effects may result from paracrine influence of the transplanted cells on the resident macrophage population of the liver. The transplantation favors polarization of macrophages to M2 phenotype(the M2-polarized macrophages specifically express CD206; they are known to suppress inflammation and support tissue repair). No differentiation of the transplanted cells into a

关键词： Liver Regeneration Multipotent stromal cells Macrophages

Spectral Investigations of Hybrid Nanostructures Including Modified Fullerene C60 and Carbazole-Derivative Fluorophore

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Advances in Nanoparticles 2014年第3期3卷 77-82页

作者： Evgeny P. Grebennikov Grigory E. Adamov valery N. Charushin Konstantin S. Levchenko gennady L. Rusinov Evgeny v. Zinoviev Roman A. Irgashev Pavel S. Shmelin Institute of Organic Synthesis Urals Branch of Russian Academy of Sciences Ekaterinburg Russia OJSC “CSRIT Technomash” Moscow Russia

Hybrid nanostructures including modified fullerene C60 and fluorophoric (E)-2-Cyano-3-(9-ethyl-9Н-carbazole-3-yl)-acrylic acid (cyanoacrylic acid I) were created. Spectral properties (absorption and luminescence spectra) of the hybrid nanostructures were investigated. It was established what molecules C60 strongly affected spectral properties of cyanoacrylic acid I in the hybrid nanostructures. Luminescence quenching of fluorophore and a change of luminescence features were observed in the hybrid nanostructures.

关键词： Hybrid Nanostructures Water-Soluble Fullerene C60 Luminescence Quenching

Ultrafast Optomechanical Terahertz Modulators Based on Stretchable Carbon Nanotube Thin Films

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Ultrafast Science 2023年第6期3卷 1-9页

作者： Maksim I.Paukov vladimir v.Starchenko Dmitry v.Krasnikov gennady A.Komandin Yuriy G.Gladush Sergey S.Zhukov Boris P.Gorshunov Albert G.Nasibulin Aleksey v.Arsenin valentyn S.volkov Maria G.Burdanova Center for Photonics and 2D Materials Moscow Institute of Physics and TechnologyDolgoprudny.Russia Skolkovo Institute of Science and Technology MoscowRussia Prokhorov General Physics Institute of the Russian Academy of Sciences MoscowRussia Laboratory of Advanced Functional Materials Yerevan State UniversityYerevanArmenia Institute of Solid State Physics of the Russian Academy of Sciences ChernogolovkaRussia.

For terahertz wave applications,tunable and rapid modulation is highly *** studied by means of optical pump-terahertz probe spectroscopy,single-walled carbon nanotube(SWCNT)thin films demonstrated ultrafast carrier recombination lifetimes with a high relative change in the signal under optical excitation,making them promising candidates for high-speed ***,combination of SWCNT thin films and stretchable substrates facilitated studies of the SWCNT mechanical properties under strain and enabled the development of a new type of an optomechanical *** applying a certain strain to the SWCNT films,the effective sheet conductance and therefore modulation depth can be fine-tuned to optimize the designed *** exhibited a photoconductivity change of approximately 2 times of magnitude under the strain because of the structural modification in the SWCNT *** was used to control the terahertz signal with a modulation depth of around 100%without strain and 65%at a high strain operation of 40%.The sensitivity of modulators to beam polarization is also shown,which might also come in handy for the design of a stretchable *** results give a fundamental grounding for the design of high-sensitivity stretchable devices based on SWCNT films.

关键词： strain excitation films