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In vivo degradability and biocompatibility of a rheo-formed Mg–Zn–Sr alloy for ureteral implantation

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Journal of Magnesium and Alloys 2022年第6期10卷 1631-1639页

作者： Di Tie Renguo Guan Huinan Liu Minfang Chen Sviatlana A.Ulasevich ekaterina v.Skorb Patricia Holt-Torres Xiaopeng Lu Norbert Hort Engineering Research Center of Continuous Extrusion Ministry of EducationDalian Jiaotong UniversityDalian 116028China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Department of Bioengineering University of CaliforniaRiversideCA 92521USA School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China Infochemistry Scientific Center ITMO UniversitySt.Petersburg 192007Russia Magnesium Innovation Center-MAGIC Helmholtz Zentrum GeesthachtGeesthacht D-21502Germany

The introduction of biodegradable implant materials has significantly improved the postoperative subjective feelings of patients within the past few decades,among which magnesium alloy is widely considered a favorable choice as its appropriate biodegradability and evident antibacterial ***,we reveal a semisolid rheo-formed Mg–Zn–Sr alloy ureteral implant that displayed suitable degradability and biocompatibility in a pig *** non-dendritic microstructure was observed in the rheo-formed alloy,which led to ca.47%increase in ultimate tensile strength(from 195.0 MPa to 288.1 MPa)and more homogeneous degradation process compared with the untreated *** post-interventional inflammation or pathological changes of the test animals were observed during the implantation period,and the corrosion rate(0.22±0.04 mm·y^(-1))perfectly fitted the clinical ureteral stent indwelling *** urine bacteria numbers decreased from 88±13 CFU·mL^(-1)at 7 weeks post operation to 59±8 CFU·mL^(-1)at 14 weeks post operation,which confirmed the evident antibacterial activity of the *** study demonstrates that the Mg–Zn–Sr alloy is clinically safe for urinary system,enabling its efficacious use as ureteral implant materials.

关键词： In vivo Biodegradability Biocompatibility Mg–Zn–Sr alloy Ureteral implant

Facile Synthesis of Amino Acid Decorated Water-Soluble Fullerene Derivatives with Anti-influenza Activity

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Chinese Journal of Chemistry 2023年第15期41卷 1803-1808页

作者： valeriya S.Bolshakova ekaterina O.Sinegubova Yana L.Esaulkova Alexander S.Peregudov ekaterina A.Khakina Nikita A.Slesarenko Alexander F.Shestakov vladimir v.Zarubaev Pavel A.Troshin Olga A.Kraevaya Federal Research Center for Problems of Chemical Physics and Medicinal Chemistry of RAS Academician Semenov ave.1Chernogolovka142432Russia Higher Chemical College of RAS D.1.Mendeleev University of Chemical Technology of RussiaMiusskaya square 9Moscow125047Russia St.Petersburg Pasteur Institute Mira st.14St.Petersburg197101Russia A.N.Nesmeyanov Institute of Organoelement compounds of RAS Vavylova St.28B-334Moscow119991Russia National Research University Higher School of Economics Vavylova St.7Moscow101000Russia Department of Fundamental Physics&Chemical Engineering M.V.Lomonosov Moscow State UniversityLeninskie Gory 1/51Moscow119991Russia Zhengzhou Research Institute Harbin Institute of TechnologyLongyuan East 7th 26Jinshui DistrictZhengzhouHenan 450003China Harbin Institute of Technology West Dazhi Street 92Nan Gang DistrictHarbinHeilongjiang 150001China

Comprehensive Summary Herein,we present a facile synthesis of amide-type water-soluble fullerene derivatives decorated with five residues of amino *** compared to the previously developed approaches,the proposed method enables usage of a broad range of amino acids,including those unstable under Friedel-Crafts reaction ***,it is fully tolerant to the nature of the sixth addend X in C60R5X precursor compounds and allows one to obtain fullerene derivatives with X=Cl,H,*** synthesized amide-type water-soluble fullerene derivatives demonstrated promising antiviral activities against rimantadine-resistant influenzaА/Puerto Rico/8/34(Н1N1)virus in vitro.

关键词： Fullerenes Amino acids Regioselectivity Water-solublel Influenza Antiviral

Bifurcations and the penetrating rate analysis of a model for percussive drilling

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Acta Mechanica Sinica 2010年第3期26卷 467-475页

作者： Qing-Jie Cao Marian Wiercigroch ekaterina Pavlovskaia Shao-Pu Yang Centre for Nonlinear Dynamics Research Shijiazhuang Railway Institute Shijiazhuang 050043 China School of Astronautics Haerbin Institute of Technology Haerbin 150001 China Department of Engineering Centre for Applied Dynamics Research King's College University of Aberdeen Aberdeen AB24 3UE Scotland UK

In this paper, we investigate a low dimensional model of percussive drilling with vibro-impact to mimic the nonlinear dynamics of the bounded progression. Non- holonomity which arises in the stick-slip caused by the impact during drilling fails to be correctly identified via the classical techniques. A reduced model without non-holono- mity is derived by the introduction of a new state variable, of which averaging technique is employed successfully to detect the periodic motions. Local bifurcations are presented directly by using C-L method. Numerical simulations and the penetrating rate analysis along different choices of parame- ters have been carried out to probe the nonlinear behaviour and the optimal penetrating rate of the drilling system.

关键词： Bifurcation Chaos Non-holonomity Percussive drilling

Evidence for polarization-induced phase transformations and degradation in CH_(3)NH_(3)PbI_(3)

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Nano Research 2023年第7期16卷 9435-9442页

作者： Aleksei Yu.Grishko Maria A.Komkova ekaterina I.Marchenko Alexandra v.Chumakova Alexey B.Tarasov Eugene A.Goodilin Andrei A.Eliseev Department of Materials Science MSU-BIT UniversityShenzhen 517182China Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia Department of Materials Science Lomonosov Moscow State UniversityMoscow 119991Russia European Synchrotron Radiation Facility F-38042 GrenobleFrance

In solar cells,hybrid halide perovskites operate under constant bias,thus their stability towards electric field-induced degradation is of key *** we report on evidence of previously unidentified electric field-induced transitions and degradation path of CH_(3)NH_(3)PbI_(3)(MAPbI_(3))using elemental and phase *** films of MAPbI_(3) were deposited onto 1-2μm-pitch interdigitated electrodes and subjected to direct current(DC)-*** MAPbI_(3) layer polarized withv/μm DC electric field undergoes pronounced ion redistribution to methylammonium-rich MAPbI_(3)-y(yvokes degradation of MAPbI_(3).Using nanofocus grazing-incidence wide-angle X-ray scattering(GIWAXS),we unambiguously showed that the bias voltage induces the transformation ofβ-MAPbI_(3) to metastableδ-MAPbI_(3) polymorph via alignment of polar organic cation with the electric *** transformation is partially reversible upon field ***,once formed,δ-MAPbI_(3) disrupts the morphology of pristine film and undergoes decomposition toβ-MAPbI_(3)(β-MAPI)and PbI_(2).With the aforementioned compositional and phase changes,only MA-rich part serves as the charge separation layer,while the I-rich excitation is blocked with the PbI_(2) barrier serving as holes trapping *** observations reveal the intermediate steps in electric-field-driven degradation of halide perovskites and show the role of polar cations in the process,which is instructive for further material design with higher stability metrics.

关键词： halide perovskites stability degradation electric field ionic conductivity stoichiometry

Monoribbed-Functionalized Macrobicyclic Iron(Ⅱ) Complexes Decorated with Terminal Reactive and vector Groups: Synthetic Strategy, Chemical Transformations and Structural Characterization

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Chinese Journal of Chemistry 2022年第17期40卷 2089-2105页

作者： Ilya P.Limarev Genrikh E.Zelinskii Svetlana A.Belova Pavel v.Dorovatovskii Anna v.vologzhanina ekaterina G.Lebed Yan Z.voloshin Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences 28 Vavilova stMoscow119991 Russia Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences 31 Leninsky prMoscow119991 Russia National Research Center Kurchatov Institute 1 Kurchatova plMoscow123098 Russia

General and straightforward synthetic strategy towards the iron(Ⅱ)clathrochelates with functionalizing substituents in their apical capping and one of the three chelate ribbed fragments was *** hexachloroclathrochelate precursors were prepared by the direct template condensation of dichloroglyoxime with a suitable boronic acid on the Fe^(2+) ion as a matrix and underwent a stepwise nucleophilic substitution with S_(2)-,N_(2)- or O_(2)-bis-nucleophiles,forming the alicyclic or aromatic N_(2)-,S_(2)-or O_(2)-six-membered *** on the reaction conditions and precursor-to-dinucleophile molar ratios,iron(Ⅱ)clathrochelates with one(S,O and N),two(S,O and N)or three(S and O)X_(2)-six-membered ribbed substituent(s)were *** reactivity substantially decreases in a row:Cl_(6)-Cage>Cl_(4)X_(2)-Cage(where X=S,O or,especially,N)>Cl_(2)X_(4)-Cage(where X=S or O).The reactive monoribbed-functionalized clathrochelates underwent further chemical transformations giving the target macrobicyclic complexes with terminal vector *** follows from the single crystal XRD data,their FeN_(6)-coordination polyhedra possess the geometry intermediate between a trigonal prism and a trigonal antiprism(φ=21.3°—25.20°).Fe-N distances vary from 1.887(6)to 1.933(8)Å.Their 3D-molecules,the hydrophobic–hydrophilic balance in which can be tuned using a ribbed functionalization,form in the crystals the intermolecular specific halogen bonds and/or hydrophobic interactions.

关键词： Macrocyclic compounds Clathrochelates Iron complexes Ligand reactivity Targetdelivery

Postglacial incision-infill cycles at the Borisoglebsk Upland: Correlations between interfluve headwaters and fluvial network

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International Soil and Water Conservation Research 2019年第2期7卷 184-195页

作者： Yuliya v.Shishkina ekaterina v.Garankina vladimir R.Belyaev Ilya G.Shorkunov Pavel v.Andreev Aleksey I.Bondar viktoria I.Potapova Tatiana A.verlova Faculty of Geography Department of Geomorphology and Palaeogeography and Laboratory for Soil Erosion and Fluvial ProcessesLomonosov Moscow State UniversityLeninskie Gory1Moscow 119991Russia Institute of Geography Department of Soil Geography and EvolutionRussian Academy of SciencesStaromonetnyj Lane29Moscow 119017Russia Institute of Earth Sciences of Saint-Petersburg State University St.PetersburgUniversitetskaya nab.7-9 199034Russia

The article discusses postglacial landscape transformation in the Northern Hemisphere Middle Pleistocene glaciation area located in the center of the Russian *** attempted to verify the regional paleogeographic model by reconstructing the Late Pleistocene incision-infill cycles at the Eastern Borisoglebsk Upland based on a comparison of inactive interfluves headwaters and actual fluvial network *** study was also aimed to determine the past extent of fluvial *** research of the actual and buried topography,Ethology and pedogenic properties of surface deposits was carrid out with remote sensing data interpretation,DGPS survey,and detailed description of geological cores *** study was followed by analysis of grain size,chemical and organic contents,microstructure,and numerical *** the available results,we propose a scenario of the fluvial network transformation at the Eastem Borisoglebsk Upland over the last 150 *** least four fluvial incision stages were determined while network extent has significantly changed through the Late *** can be generally associated with the regional base level decrease-Late Moscow,Late valdai and Late Holocene and accompanying isolation of the Nero Lake terraces of 130 m,100-105 m and 95-98 *** stages were separated by landscape stability or aggradation periods those were asynchronous at the middle and upper parts of the fluvial *** main agent of initial valley infill appears to be local lacustrine sedimentation altered by alluvial and colluvial deposition towards the second half of *** landscape conditions variability emphasize the importance of comprehensive local correlations for regional retrospective models.

关键词： Interfluve headwaters Fluvial Incision-Infill Cycle Pleistocene

variable retention forestry in European boreal forests in Russia

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Ecological Processes 2019年第1期8卷 424-434页

作者： ekaterina Shorohova Sergey Sinkevich Aleksandr Kryshen Ilkka vanha-Majamaa Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences Pushkinskaya str.11Petrozavodsk 185910Russia Saint-Petersburg State Forest Technical University Institutsky str.5Saint Petersburg 194021Russia Natural Resources Institute Finland(Luke)Latokartanonkaari 9FI-00790 HelsinkiFinland

We explored whether,and to what extent,variable retention(vR)forestry has been applied in European boreal forests in northwestern *** survey revealed vR since *** 1910 and the 1960s,the statistics showing how much was retained are largely ***,for example,in the 1950s,on a large scale in the Republic of Karelia,up to 200-ha-sized harvesting areas,18–33%,were retention patches with a mean growing stock of 30–40m3 ha−*** the fellings defined as“incomplete clear fellings,”which were the most common final felling type at that time,11–40%of the growing stock was *** the 1960s and the early 1990s,with more efficient harvesting and skidding techniques,conventional clear fellings with a much lower amount of retention were *** about the regeneration of harvested areas gradually led to smaller(maximum 50 ha)harvesting areas and the increase of silvicultural *** now,to ensure natural regeneration,patches of understory and 20–25 seed trees(i.e.,ca.15–25m3)per ha have been left permanently in harvesting ***-scale retention for protecting ecosystem functions and biodiversity was legislated in 1978 by preserving key biotopes up to 1000 ha in *** 2001,promoted by forest certification,the key biotopes,such as paludified forest patches,buffers around water bodies,and habitats of red-listed species,have also been retained in harvesting areas,together with a dispersed retention of different *** estimates of the amount of key biotopes are largely ***,estimates of 1–13%in harvesting areas and 23%in whole managed landscapes have been *** applied during the last century has emulated natural disturbances and created diverse uneven-aged forest structures with high amounts of diverse coarse woody *** conclude that an analysis of past and current retention practices is essential for estimating the global role of Russian *** decisions on the general direction

关键词： Biological legacies Nature conservation Biodiversity Clear felling Key biotopes Coarse woody debris,Silviculture Dispersed and aggregated retention

Lake-margin ecosystems of saline lakes of the Borzya group(Zabaikalsky Krai, Russia) during the initial filling phase

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Chinese Journal of Oceanology and Limnology 2014年第4期32卷 871-878页

作者： Evgenia P.GORLACHEvA Gazhit Ts.TSYBEKMITOvA Alexey v.AFONIN Natalya A.TASHLIKOvA ekaterina Yu.AFONINA Alexey P.KUKLIN Natalia v.SALTANOvA Institute of Natural Resources Ecology and Cryology Siberian Branch of Russian Academy of Sciences16 a Nedorezov St Chita 672014Russia

This article presents the results of hydrochemical and hydrobiological studies of shallow saline lakes of the Borzya group(Zabaikalsky Krai, Russia) at the initial filling phase. The lake-margin ecosystems of the studied lakes are characterized by varying degrees of salinity from polyhaline to brine water. Cyclical variations of meteorological conditions and high salinity determined that the compositions of the aquatic organisms are specific, mostly between stenohaline and euryhaline species, the quantities are low, and the community structures are simple.

关键词： saline lakes hydrochemistry weeds zooplankton zoobenthos

Relaxation of Mechanical Stress in Poly(vinyl alcohol) Cryogels of Different Compositions

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Chinese Journal of Polymer Science 2023年第3期41卷 442-447,I0010页

作者： vladimir N.Manzhai Maria S.Fufaeva ekaterina S.Kashlach Institute of Petroleum Chemistry of the Siberian Branch of the Russian Academy of Sciences Tomsk 634055Russia

The study presents the experimental results of measurements of the relaxation time of cryogels formed from various colloid-dispersed systems based on a poly(vinyl alcohol) aqueous *** is shown that the value of relaxation time,which characterizes the relationship between the viscosity and elasticity of real bodies,describes the rheological properties of materials more objectively than the traditional assessment of their physical and mechanical characteristics only by the elasticity modulus of the samples.

关键词： Cryogel Relaxation processes viscoelasticity Rheological properties