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Silica-based nanoarchitecture for an optimal combination of photothermal and chemodynamic therapy functions of Cu2–xS cores with red emitting carbon dots

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 2144-2155页

作者： alexey Stepanov Svetlana Fedorenko Kirill Kholin Irek Nizameev alexey Dovzhenko Rustem Zairov Tatiana Gerasimova Alexandra Voloshina Anna Lyubina Guzel Sibgatullina Dmitry Samigullin Asiya Mustafina Arbuzov Institute of Organic and Physical Chemistry FRC Kazan Scientific Center of RASKazan 420088Russia Department of Physics Kazan National Research Technological UniversityKazan 420015Russia Department of Nanotechnology in Electronics Kazan National Research Technical University named after A.N.Tupolev-KAIKazan 420111Russia Kazan(Volga region)Federal University Kazan 420008Russia Kazan Institute of Biochemistry and Biophysics FRC Kazan Scientific Center of RASKazan 420111Russia

This study introduces multifunctional silica nanoparticles that exhibit both high photothermal and chemodynamic therapeutic activities,in addition to *** activity of the silica nanoparticles is derived from their plasmonic properties,which are a result of infusing the silica nanoparticles with multiple Cu2-xS *** infusion process is facilitated by a recoating of the silica nanoparticles with a cationic *** key factors that enable the internal incorporation of the Cu2-xS cores and the external deposition of red-emitting carbon dots are *** Cu2-xS cores within the silica nanoparticles exhibit both self-boosting generation of reactive oxygen species and high photothermal conversion efficacy,which are essential for photothermal and chemodynamic *** silica nanoparticles’small size(no more than 70 nm)and high colloidal stability are prerequisites for their cell *** internalization of the red-emitting silica nanoparticles within cells is visualized using fluorescence microscopy *** chemodynamic activity of the silica nanoparticles is associated with their dark cytotoxicity,and the mechanisms of cell death are evaluated using an apoptotic *** photothermal activity of the silica nanoparticles is demonstrated by significant cell death under near-infrared(1064 nm)irradiation.

关键词： copper sulfide nanoparticles chemodynamic therapy photothermal therapy carbon dots silica nanoparticles

The ecosystem of Lake Kenon:past and present(Transbaikal Territory,Russia)

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Chinese Journal of Oceanology and Limnology 2016年第3期34卷 507-516页

作者： alexey P.KUKLIN Gazhit Ts.TSYBEKMITOVA Evgenia P.GORLACHEVA Balzhit B.BAZAROVA alexey V.AFONIN Institute of Natural Resources Ecology and Cryology Siberian Branch of Russian Academy Science

Present-day conditions of the Lake Kenon ecosystem are determined by a combination of natural and anthropogenic factors. We have estimated the effects of a complex of factors on the condition of the abiotic environment and on specific biological components in the lake ecosystem. Change in biogenic load has caused an increase in the role of phytoplankton in the general balance of organic matter during the high-water period. Charophytes are the main dominants of bottom vegetation. Anthropogenic load has caused a decrease in both fish species and fish capacity. The lake application as a water reservoir-cooler has influenced the average annual water mineralization （from 420 mg/L to 530.0 mg/L with a maximum 654 mg/L in 1993） and fluctuations in its hydrochemical composition. The present composition of the lake is sulfate-hydrocarbonate-chloride calcium-sodic-magnesium in character. S（Y44 content is twice as much as the maximum permissible concentration in fishery waters. Water drainage from an ash disposal area to the lake has caused an increase in chemical-element concentrations including the heavy metals. Hg concentration in Perca fluviatilis muscles is 0.5 9g/g dry wt. Thus, understanding directions in the ecosystem of the water reservoir-cooler under changing hydrological conditions will let us forecast the consequences of new combined heat and power plant operation.

关键词： water reservoir-cooler of combined heat and power plant (CHP) hydrochemistry ichthyofauna biodiversity the chemical elements

A Global Perspective on Crustal Structure and Evolution based on A New Crustal Classification

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Acta Geologica Sinica(English Edition) 2021年第S1期95卷 48-50页

作者： Irina M.ARTEMIEVA alexey SHULGIN School of Earth Sciences China University of GeosciencesWuhan 430074China Marine Geodynamics GEOMAR Helmholtz Center for Ocean ResearchKielGermany Department of Geophysics Stanford UniversityCAUSA CEED University of OsloNorway

Knowledge of the crustal structure is the key for understanding physical and chemical conditions of its formation and later modification by geodynamic *** has long been recognized that crustal structure is controlled by tectonic settings,and that the crustal thickness is one of the most important parameters that reflects the geodynamic origin of the crust.A long tectonic life of continental crust leads to its significant reworking by plate tectonics processes and crust-mantle interaction,which include mechanical extension.

关键词： crustal delamination granitization basin subsidence orogenic processes continental rifting hotspots continental shelves failed oceans oceanic crust

Evaluating grant proposals:lessons from using metrics as screening device

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数据与情报科学学报:英文版 2023年第2期8卷 66-92页

作者： Katerina Guba alexey Zheleznov Elena Chechik Center for Institutional Analysis of Science and Education European University at Saint PetersburgGagarinskaya 6/1A Saint Petersburg 191178Russian Federation

Purpose:This study examines the effects of using publication-based metrics for the initial screening in the application process for a project *** key questions are whether formal policy affects the allocation of funds to researchers with a better publication record and how the previous academic performance of principal investigators is related to future project ***/methodology/approach:We compared two competitions,before and after the policy raised the publication threshold for the principal *** analyzed 9,167 papers published by 332 winners in physics and the social sciences and humanities(SSH),and 11,253 publications resulting from each funded ***:We found that among physicists,even in the first period,grants tended to be allocated to prolific authors publishing in high-quality *** contrast,the SSH project grantees had been less prolific in publishing internationally in both periods;however,in the second period,the selection of grant recipients yielded better results regarding awarding grants to more productive authors in terms of the quantity and quality of *** was no evidence that this better selection of grant recipients resulted in better publication records during grant ***:This study contributes to the discussion of formal policies that rely on metrics for the evaluation of grant *** Russian case shows that such policy may have a profound effect on changing the supply side of applicants,especially in disciplines that are less suitable for metric-based *** spite of the criticism given to metrics,they might be a useful additional instrument in academic systems where professional expertise is corrupted and prevents allocation of funds to prolific researchers.

关键词： Grant funding Research evaluation Publication-based metrics Funding allocation

Low-frequency laboratory measurements of the elastic properties of solids using a distributed acoustic sensing system

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2330-2338页

作者： Vassily Mikhaltsevitch Maxim Lebedev Roman Pevzner alexey Yurikov Konstantin Tertyshnikov Curtin University GPO Box U1987PerthWA 6845Australia Centre for Sustainable Energy and Resources Edith Cowan University270 Joondalup DrJoondalupWA 6027Australia

In recent decades,low-frequency(LF)experiments based on the forced-oscillation(FO)method have become common practice in many rock physics laboratories for measuring the elastic and anelastic properties of ***,the use of the electronic displacement sensors in traditional acquisition systems of FO devices such as conventional capacitive transducers or strain gauges seriously limits both the efficiency and productivity of LF measurements,and,due to the limited contact area of the displacement sensors with a sample under test,increases the requirements for sample *** this paper,we present the first results obtained in the development of a new laboratory method elaborated to measure the elastic properties of *** method is a further development of the FO method where traditional data acquisition is replaced by acquisition based on fiber-optic distributed acoustic sensing(DAS)*** new method was tested in a laboratory study using two FO setups designed for measurements under uniaxial and confining *** study was carried out on a sample made from polymethyl methacrylate(PMMA)and an aluminium standard,first under uniaxial pressure at FO frequencies of 1,10,30,60 and 100 Hz,and then under confining pressure at an FO frequency of 1 *** uniaxial and confining pressures were equal to 10 MPa,and the strain in the PMMA sample in all measurements did not exceed 4×10^(-8).The performance of DAS acquisition was compared with the measurements conducted at a strain of 1×10^(-6) using the traditional FO method based on the use of semiconductor strain gauges and the ultrasonic *** results of the DAS measurements are in good agreement with the FO measurements carried out using semiconductor strain gauges and with the literature data.

关键词： Elasticity and anelasticity Acoustic properties Fourier analysis Wave propagation

Fast Square Root Calculation without Division for High Performance Control Systems of Power Electronics

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CES Transactions on Electrical Machines and Systems 2022年第2期6卷 145-152页

作者： Anton Dianov Alecksey Anuchin alexey Bodrov Daeyoung R&D center 16954YonginKorea National Research University“Moscow Power Engineering Institute” 111250MoscowRussia School of Engineering the University of ManchesterManchesterUK

The calculation of square roots is a frequently used operation in control systems of power electronics for different applications:motor drives,power converters,*** the same time,the execution of this procedure significantly loads microcontrollers and uses its power,which can be utilized for performing other important ***,it restricts the size of code,which can be processed by the microcontroller and compels developers to limit the number of functions,or to decrease execution frequency of a ***,the calculation of square roots is a bottle-neck in implementation of high-performance control systems,thus effective optimization of this task is extremely important in modern and efficient *** respect that many applications do not need precise calculation of square roots,the optimization of execution time can be achieved by decreasing of precision of the *** proposed technique is based on the approximation of parabola with hyperbola,which allows you to rapidly find the approximate value of a square *** into account that many digital signal processors(DSP)are not equipped with an effective divider,the developed algorithm does not use divisions,so it can be executed *** payback for this optimization is approximation error with a maximum of 0.5%,however,it is acceptable for the overwhelming majority of control systems.

关键词： Approximate computing Approximation algorithms Newton method Numerical methods

Late Paleozoic alkaline magmatism in Western Transbaikalia,Russia:Implications for magma sources and tectonic settings

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Geoscience Frontiers 2020年第4期11卷 1289-1303页

作者： Ivan Izbrodin Anna Doroshkevich Mikhail Rampilov alexey Elbaev German Ripp Geological Institute Siberian Branch of the Russian Academy of SciencesRussia V.S.Sobolev Institute of Geology and Mineralogy Siberian Branch of the Russian Academy of SciencesRussia

This paper presents the results of geochronological(40Ar-39Ar,U-Pb SHRIMP Ⅱ),petrological and geochemical studies of the Late Paleozoic complexes of alkaline rocks(Zimovechinsky,Tuchinsky and Koma) located within the Vitim Plateau(the western part of the Mongol-Okhotsk Orogenic Belt).The rocks were formed at 310-280 *** is coeval with Late Paleozoic magmatism within the Central Asian Orogenic *** εNd(T) values show large variations from-2.1 to +3.3 as well as the initial Sr(I) isotopic ratios from 0.7042 to 0.7138,that demonstrate strong isotopic heterogeneity of the magmatic *** geochemical characteristics of the rocks show pronounced positive Pb and negative Ti,Zr-Hf anomalies that can be explained by involvement of the subducted component in primary *** rocks intruded in a setting of extension at the active continental margin of the Siberian Craton during subduction of Mongol-Okhotsk oceanic crust under the Siberian Craton.

关键词： Nepheline-bearing and nepheline-free syenites Geochronological and isotope data Late paleozoic magmatism Sources Central Asian orogenic belt

Asymmetry ratio as a parameter of Eu^3＋ local environment in phosphors

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Journal of Rare Earths 2018年第5期36卷 474-481页

作者： Ilya E. Kolesnikov alexey V. Povolotskiy Daria V. Mamonova Evgeny Yu. Kolesnikov alexey V. Kurochkin Erkki Lahderanta Mikhail D. Mikhailov Saint Petersburg State University 7/9 Universitetskaya nab. 199034 St.petersburg.Russia Lappeenranta University of Technology LUT Skinnarilankatu 34 53850 Lappeenranta Finland Scientific and Technological Institute of Optical Material Science VNTs S. I. Vavilov State Optical Institute Babushkina 36-1 192171 St. Petersburg Russia Volga State University of Technology Lenin Sq. 3 424000 Yoshkar-Ola Russia

Study of the local environment of certain ion is quite a complex problem. Due to the unique luminescent properties, Eu^3＋ ions can be used as a structural probe. In this paper, effect of doping concentration,excitation wavelength and excitation mechanism on asymmetry ratio was systematically studied using Y3Al5O12：Eu^3＋, YVO4：Eu^3＋ and Y2O3：Eu^3＋nanophosphors. The asymmetry ratio gives information about the local surrounding and environmental changes around the Eu^3＋ ions. Asymmetry ratios of YAG：Eu^3＋and YVO4：Eu^3＋ nanopowders were calculated using standard technique and the obtained average values were found to be 0.75 and 8.2, respectively. However, it is found that standard method of asymmetry ratio calculation is suitable only for samples where all Eu^3＋ ions occupy one site. The ＂multisite model＂ of asymmetry ratio calculation was developed and used for Y2O3：Eu^3＋ nanocrystalline powders. Average value of asymmetry ratio for Eu^3＋ ions occupied ＂normal＂ sites is 6.0 and for Eu^3＋ ions occupied ＂defect＂sites is 2.3.

关键词： Eu3+ Oxide powders Luminescence Asymmetry ratio Structural probe Rare earths

Thermal state calculation of chamber in small thrust liquid rocket engine for steady state pulsed mode

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Chinese Journal of Aeronautics 2019年第2期32卷 253-262页

作者： alexey Gennadievich VOROBYEV Svatlana Sergeevna VOROBYEVA Lihui ZHANG Evgeniy Nikolaevich BELIAEV Department of Rocket Engines Moscow Aviation Institute School of Astronautics Beihang University

This paper presents a method of thermal state calculation of combustion chamber in small thrust liquid rocket engine. The goal is to predict the thermal state of chamber wall by using basic parameters of engine: thrust level, propellants, chamber pressure, injection pattern, film cooling parameters, material of wall and their coating, etc. The difficulties in modeling the startup and shutdown processes of thrusters lie in the fact that there are the conjugated physical processes occurring at various parameters for non-design conditions. A mathematical model to predict the thermal state of the combustion chamber for different engine operation modes is developed. To simulate the startup and shutdown processes, a quasi-steady approach is applied by replacing the transient process with time-variant operating parameters of steady-state processes. The mathematical model is based on several principles and data commonly used for heat transfer modeling: geometry of flow part, gas dynamics of flow, thermodynamics of propellants and combustion spices, convective and radiation heat flows, conjugated heat transfer between hot gas and wall, and transient approach for calculation of thermal state of construction. Calculations of the thermal state of the combustion chamber in single-turn-on mode show good convergence with the experimental results. The results of pulsed modes indicate a large temperature gradient on the internal wall surface of the chamber between pulses and the thermal state of the wall strongly depends on the pulse duration and the interval.

关键词： Combustion chamber Film cooling Mathematical model Nonstationary thermal mode Small thrust liquid rocket engine Steady pulse mode Thermal state