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Highly Heat-Resistant Materials for Microelectronics:Hydrodynamic,Optical,and Conformational Properties of Fluorine Containing Poly(Amido-ortho-Hydroxy Amide)

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 223-230页

作者： Irina A Strelina Liudmila I Rudaya Ol’ga V Okatova Maxim N Bol’shakov aleksey yumarfichev Galina K Lebedeva Yuliya V Shagayko Stanislav M Ramsh Institute of Macromolecular Compounds Russian Academy of SciencesBolshoi pr.VO 31St Petersburg199004 Russia Saint-Petersburg State Institute of Technology(Technical University) Moskovskii pr.26St Petersburg190013 Russia

The polycondensation of the mixture of diamines 5,5-methylene bis(2-aminophenol) and 4,4-(hexafluoroisopropylidene)dianiline(molar ratio 0.8:0.2) with isophthaloyl dichloride was used to synthesize poly(amido-o-hydroxy amide)(POA-F)-new heat resistant binder of the composites for microelectronics. The copolymer was fractionated, its hydrodynamic, optical, and conformational properties were researched, and molecular masses(ММ) of the fractions were defined. The polydispersity index was estimated. Based on experimental data, calculation of the size of a segment of Kuhn characterizing degree of an intramolecular orientation order and value of coefficients of the equation of Mark-Kuhn-Hauvink for viscometric and diffusion data were performed. It was demonstrated that introducing 20 mol % of the monomer with-CF3-groups does not lead to any changes in conformational properties of the macromolecules and does not change the degree of intramolecular orientational order(the Kuhn segment length). Optical characteristics of POA-F solutions are virtually similar to the corresponding values for POA prepared with the use of single amine-containing component-5,5-methylene bis(2-aminophenol). The received MM distribution for POA-F(prepolymer) provided the solubility of its films in alkaline solutions. The heat resistance(τ5 and τ10-temperatures corresponding to 5% and of 10% PBO-F mass loss of a polymer) of the powders and the films of PBO, PBO-F were determined. The electrophysical parameters-dielectric permittivity(ε) and dielectric loss tangent(tan δ) of the PBO-F films decreased down to 3.30 and 0.017, in comparison 3.40 and 0.025 for PBO respectively.

关键词： poly(o-hydroxy amide) 4,4-(hexafluoroisopropylidene) dianiline Kuhn segment Mark-Kuhn-Houwink equations translational diffusion intrinsic viscosity flow birefringence

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The effect of the concentration of plastic waste on the formation of reaction products of the Ti–PET system

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Green Chemical Engineering 2024年第3期5卷 374-382页

作者： aleksey E.Matveev Tomsk Scientific Center of the Siberian Branch of the Russian Academy of Sciences

The paper presents research results of the synthesis, phase composition, and structure of products obtained by highly exothermic reactions between Ti and C10H8O4mixture components, depending on the plastic waste concentration and Ti powder dispersiveness, density of initial samples, and synthesis medium. The dependence of the phase composition and structure of the synthesis products on the concentration of the polymer（plastic）component in the initial Ti-PET(C10H8O4) system was found. When the plastic waste content is 20 wt% to 25 wt%, synthesis products contain TiC0.5O0.5–TiC0.6–0.75particle agglomerates. Further growth in the polyethylene terephthalate content from 30 wt% to 45 wt% leads to the formation of synthesis products consisting of titanium carbide(TiC0.6–1.0). The gaseous byproduct composition of the exothermic reaction is investigated for the Ti–-C10H8O4mixture composition. It is found that the gaseous by-product mostly contains hydrogen and carbon monoxide as well as impurities of different hydrocarbons（methane, acetylene, ethane, ethene） and carbon dioxide. The maximum adiabatic temperature of the gas combustion temperature is 2080℃, which demonstrates the possibility of using gas as a fuel for energy generation devices. Based on the data obtained, it is possible to create a basis for a new plastic waste technology to fabricate carbide-containing materials.

关键词： Plastic waste Titanium carbide Green technology Hydrogen synthesis

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Normal Crossings Singularities for Symplectic Topology:Structures

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Acta Mathematica Sinica,English Series 2024年第1期40卷 107-160页

作者： Mohammad FARAJZADEH-TEHRANI Mark MCLEAN aleksey ZINGER The University of Iowa MacLean HallIowa CityIA 52241 Department of Mathematics Stony Brook UniversityStony BrookNY 11794

Our previous papers introduce topological notions of normal crossings symplectic divisor and variety,show that they are equivalent,in a suitable sense,to the corresponding geometric notions,and establish a topological smoothability criterion for normal crossings symplectic *** present paper constructs a blowup,a complex line bundle,and a logarithmic tangent bundle naturally associated with a normal crossings symplectic divisor and determines the Chern class of the last *** structures have applications in constructions and analysis of various moduli *** a corollary of the Chern class formula for the logarithmic tangent bundle,we refine Aluffi’s formula for the Chern class of the tangent bundle of the blowup at a complete intersection to account for the torsion and extend it to the blowup at the deepest stratum of an arbitrary normal crossings divisor.

关键词： Normal crossings divisor Chern class Logarithmic tangent bundle

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Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Journal of Forestry Research 2024年第2期35卷 70-80页

作者： aleksey S.Ilintsev Elena N.Nakvasina Alexander P.Bogdanov Northern Research Institute of Forestry 13 Nikitova Str.Arkhangelsk 163062Russian Federation Department of Silviculture and Forest Management Northern(Arctic)Federal University Named After M.V.LomonosovSevernoy Dviny Emb.17Arkhangelsk 163002Russian Federation

This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of *** study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess *** the rooting layer,240 soil samples were taken to determine physical *** study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina ***,reduced soil moisture was noted,particularly in mounds,resulting in increased *** Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the *** treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration *** the Myrtillus and Polytrichum sites,patch scarification had no effects on physical *** Polytrichum sites,survival rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to *** Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil *** conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.

关键词： Boreal forests Mechanical site preparation Patch scarification Mounding Soil properties Containerised seedlings Bareroot seedlings

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Time for a New Paradigm in Oncology? Viewpoint of the Radiobiologist

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Open Journal of Biophysics 2024年第1期14卷 11-55页

作者： aleksey N. Shoutko Department of Transplantation and Cells Technologies Russian Research Center of Radiology and Surgical Technologies Named after A. M. Granov Saint-Petersburg Russia

The current immunooncology artificially ignores the connection with lymphopoiesis, though is only its derivative. Hematopoietic stem cells (HSC) provide physiological regeneration of biomass of the host, fetus, and malignant tumors, as well, as the cells’ reparation after sub-lethally injuring in any tissues and their renewal. HSC, especially of lymphoid lineage, are the most vulnerable of those, which are responsible for viability of organism. Natural and artificial deficits of HSC determine aging, multi-organs syndromes and death of the host, because their current proliferative resource (CPR) is individually limited at birth, and is spending irreversibly during wounds’ healing, pregnancy, tumor growth, and on. CPR, being an integral value of the number of stem cells along the length of their telomeres, is a “shagreen skin”, for which the tumor competes with normal tissues as a quasi-embryonic favorite and winner, especially in the final period of a shortening the life. The primary approach to cancer treatment must prioritize the preservation of CPR remnants, rather than their destruction, in order to temporarily halt the malignant process. The re-targeting of HSC from tumors in favor of normal tissues is the immediate objective of competitive therapy, which allows for preserving the rest of the CPR host’s resources, especially in patients with advanced cancer. However, the contradictory and insignificant practically, the dogma of antitumor cellular immunity continues to dominate and hinder progress in oncology.

关键词： Lymphopoiesis Proliferating Resource Morphogenesis Cancer-Fetus Reparation-Regeneration Competitive Therapy

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Porous Shish-Kebab Structure Prepared from Oriented UHMWPE Films by Processing in Supercritical CO_(2)

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Chinese Journal of Polymer Science 2024年第1期42卷 97-104,I0009页

作者： Sergey A.Lermontov aleksey V.Maksimkin Nataliya A.Sipyagina Tarek Dayyoub Alena N.Malkova Evgeniy A.Kolesnikov Elena A.Straumal Inna O.Gozhikova Saidkhodzha G.Nematulloev Dmitry V.Telyshev Institute of Physiologically Active Compounds of the Russian Academy of Sciences Chernogolovka 142432Russia Institute for Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 19991Russia National University of Science and Technology"MISIS"Moscow 119049 Russia Institute of Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia

For the first time, a highly crystalline porous shish-kebab structure with a high degree of crystallinity was obtained by using a combination of two methods for the formation of porous polymeric materials. A treatment procedure using supercritical carbon dioxide(sc CO_(2))was carried out for oriented ultrahigh molecular weight polyethylene(UHMWPE) films, which provided special conditions for the crystallization of dissolved UHMWPE macromolecules on the surface of oriented UHMWPE crystals. The prepared porous materials were investigated by scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). The particularity of the obtained porous shish-kebab is the absence of the amorphous phase between lamellar crystals(kebabs). The obtained pores had an oval shape, and they were oriented in the orientation direction of the UHMWPE macromolecules. The pore size ranged from 0.05 μm to 4 μm. Controlling the conditions for the crystallization of the UHMWPE macromolecules using supercritical CO_(2) gives the possibility to control the size of both lamellar disks and pores formed.

关键词： UHMWPE Supercritical CO_(2) Porous shish-kebab structure

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Comprehensive,Continuous,and Vertical Measurements of Seawater Constituents with Triple-Field-of-View High-Spectral-Resolution Lidar

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Research 2024年第2期2023卷 191-201页

作者： Kai Zhang Yatong Chen Hongkai Zhao Zhongping Lee Emmanuel Boss Iwona Stachlewska Davide Dionisi Cedric Jamet Paolo D.Girolamo aleksey Malinka Chengchong Jiang Hongda Wu Lingyun Wu Feitong Chen Xiaolei Zhu Nanchao Wang Chuxiao Chen Qun Liu Lan Wu Yudi Zhou Weibiao Chen Dong Liu Ningbo Research Institute State Key Laboratory of Modern Optical InstrumentationCollege of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China ZJU-Hangzhou Global Scientific and Technological lnnovation Center Zhejang UniversityHangzhou 311200China Donghai Laboratory.Zhoushan 316021 China State Key Lab of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China School of Marine Sciences University of MaineOronoME 04469-5741USA Faculty of Physics University of WarsawWarsaw 02093Poland institute of Marine Sciences Italian National Research CouncilRome 00133Italy Universitédu Littoral Cote d'Opale CNRSUniv.LilleIRDUMR 8187-LOG-Laboratoire d'Oceanologie et de GéosciencesWimereux F-6293 Francen Institute Scuola di Ingegneria Universita della BasilicataPotenza 85100Italy Institute of Physics National Academy of Sciences of BelarusMinsk 220072Belarus Key Laboratory of Space Laser Communication and Detection Technology Shanghai lnstitute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Inteligent Optics&Photonics Research Center Jiaxing Research Institute Zhejiang UniversityJiaxing 314000China Jiaxing Key Laboratory of Photonic Sensing&Intelligent Imaging Jiaxing 314000China

Measuring the characteristics of seawater constituent is in great demand for studies of marine ecosystems and ***,existing techniques based on remote sensing or in situ samplings present various tradeoffs with regard to the diversity,synchronism,temporal-spatial resolution,and depth-resolved capacity of their data ***,we demonstrate a novel oceanic triple-field-of-view(FOV)high-spectral-resolution lidar(HSRL)with an iterative retrieval *** technique provides,for the first time,comprehensive,continuous,and vertical measurements of seawater absorption coefficient,scattering coefficient,and slope of particle size distribution,which are validated by simulations and field ***,it depicts valuable application potentials in the accuracy improvement of seawater classification and the continuous estimation of depth-resolved particulate organic carbon *** triple-FOV HSRL with high performance could greatly increase the knowledge of seawater constituents and promote the understanding of marine ecosystems and biogeochemistry.

关键词： lidar Vertical seawater

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Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet N.Toksumakov Olga G.Matveeva Dmitriy V.Grudinin Kirill V.Voronin Arslan Mazitov Konstantin V.Kravtsov Alexander V.Syuy Dmitry M.Tsymbarenko Mikhail S.Mironov Sergey M.Novikov Ivan Kruglov Davit A.Ghazaryan Andrey A.Vyshnevyy aleksey V.Arsenin Valentyn S.Volkov Kostya S.Novoselov Moscow Center for Advanced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene Institute(NGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

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Polyhydroxybutyrate/Hydroxyapatite Highly Porous Scaffold for Small Bone Defects Replacement in the Nonload-bearing Parts

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Journal of Bionic Engineering 2017年第4期14卷 648-658页

作者： Fedor Senatov Natalia Anisimova Mikhail Kiselevskiy aleksey Kopylov Viktor Tcherdyntsev aleksey Maksimkin National University of Science and Technology MISIS Leninskiy pr. 4 Moscow 119049 Russian Federation N.N. Blokhin Russian Cancer Research Center Kashirskoye sh. 23 Moscow 115478 Russian Federation

In the present work, Polyhydroxybutyrate （PHB）/Hydroxyapatite （HA） porous composites （10%, 20%, 30 %, 40%, 50% weight HA） were obtained by sintering. PHB/20% HA optimally combines satisfactory mechanical properties with a high content of the bioactive component （HA）. Porous PHB/20% HA scaffolds have shown high mechanical properties （compressive strength of 106 MPa and Young＇s modulus of 901 MPa）. A high volume fraction of interconnected pores （〉 50 vol.%） was achieved with pore size of 50 grn - 500 gm. Biocompatibility of porous pure PHB and PHB/20%HA, as its osseointegration were assessed in vitro and after implantation in laboratory animals. PHB/20% HA （-5% ＋ 0.9%） and pure PHB ~3% ~ 1.4%） samples after 24 hours of incubation with human leucocytes showed no significant level of cytotoxicity when p = 0.648 （p-value）. In vitro massive adhesion of mouse Multipotent Mesenchymal Stromal Cells （MMSC） to the surface of both porous samples was shown. PHB/20% HA induced more intensive MMSC proliferation compared to pure PHB, which are 31% ＋ 6.1% and 20% ＋ 5.7 % respectively when p = 0.039. We observed the resorption （implant surface area was reduced by 49 %） and integration of the porous PHB/20% HA samples into surrounding tissues after 30 days of implantation. The signs of osteoclasts accumulation, neo-angigenesis and new bone formation were observed, which make PHB/20% HA promising for bone tissue engineering.

关键词： polyhydroxybutyrate hydroxyapatite scaffold porous structure implant bone regeneration

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Composite Control of Nonlinear Singularly Perturbed Systems via Approximate Feedback Linearization

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International Journal of Automation and computing 2020年第4期17卷 610-620页

作者： aleksey Kabanov Vasiliy Alchakov Sevastopol State University Sevastopol 299053Russian Federation

This article is devoted to the problem of composite control design for continuous nonlinear singularly perturbed(SP)system using approximate feedback linearization(AFL)*** essence of AFL method lies in the feedback linearization only of a certain part of the original nonlinear *** to AFL approach,we suggest to solve feedback linearization problems for continuous nonlinear SP system by reducing it to two feedback linearization problems for slow and fast subsystems *** resulting AFL control is constructed in the form of asymptotic composition(composite control).Standard procedure for the composite control design consists of the following steps:1)system decomposition,2)solution of control problem for fast subsystem,3)solution of control problem for slow subsystem,4)construction of the resulting control in the form of the composition of slow and fast *** main difficulty during system decomposition is associated with dynamics separation condition for nonlinear SP *** overcome this,we propose to change the sequence of the design procedure:1)solving the control problem for fast state variables part,2)system decomposition,3)solving the control problem for slow state variables part,4)construction of the resulting composite *** this way,fast feedback linearizing control is chosen so that the dynamics separation condition would be met and the fast subsystem would be *** application of the proposed approach is illustrated through several examples.

关键词： Approximate feedback linearization(AFL) composite control nonlinear singularly perturbed system order reduction decomposition

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