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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

Olefin Polymerization Behavior of Titanium(Iv) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： vladislav A.Tuskaev Kasim F.magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia v.Nelyubina Evgenii K.Golubev.m.ria D.Evseeva viktor G.vasil'ev Galina G.Nikiforova mikhail I.Buzin vyacheslav S.bogdanov Boris m.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(mmAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(m_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHmWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(Iv) (Co)polymerization Al/mg co-catalyst Ultra-high molecular weight polyethylene

Effect of Ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on mg-alloy

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Journal of magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： D.v.m.shtalyar I.m.Imshinetskiy v.v.Kashepa K.v.Nadaraia m.A.Piatkova A.I.Pleshkova K.A.Fomenko A.Yu.Ustinov S.L.Sinebryukhov S.v.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Dermatovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on mA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

Photoluminescence,structural and antibacterial properties of co-dopedβ-Ca_(3)(PO_(4))_(2)-type phosphates Ca_(8)CuRE(PO_(4))_(7)(RE=Eu-Er)

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Journal of Rare Earths 2024年第9期42卷 1658-1668,I0002页

作者： Ivan v.Nikiforov Ekaterina v.Iliin Bogdan I.Lazoryak Sergey m.Aksenov Pavel v.Slukin Dina v.Deyneko Department of Chemistry Lomonosov Moscow State University119991MoscowRussia Laboratory of Arctic mineralogy and material Sciences Kola Science CentreRussian Academy of Sciences184209ApatityRussia Geological Institute Kola Science CentreRussian Academy of Sciences184209ApatityRussia State Scientific Center of Applied microbiology and Biotechnology of Rospotrebnadzor 24 Block A142279ObolenskRussia

Novel Ca_(8)CuRE(PO_(4))_(7)where RE^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Ho^(3+)and Er^(3+)were synthesized by a solid-state method in *** structures of the samples were characterized by powder X-ray diffraction using Rietveld refinement to determine the occupation of crystal *** samples are found to have a centrosymmetric structure with space group R3c,as shown by dielectric *** synthesized Ca_(8)CuRE(PO_(4))_(7)samples have multifunctional *** Cu^(2+)ions provide antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and theβ-Ca_3(PO_(4))_(2)-type host is *** photoluminescence properties of RE^(3+)ions were studied and compared with other simmilar Ca_(8)mRE(PO_(4))_(7)phosphates,where m is a divalent *** photoluminescence intensity quenching in terms of energy transfer from RE^(3+)to Cu^(2+)is *** bioactive properties were studied in relation to antibacterial activity against *** and *** syntesized Ca_(8)CuRE(PO_(4))_(7)samples demonstrate very high and stable inhibition of bacteria *** correlation between crystal structure and properties is *** combining multiple approaches to the directio nal design of such materials,several important properties within a single chemical compound to achieve biovisualization and bioactive properties simultaneously can be combined.

关键词： β-Ca_(3)(PO_(4))_(2) Whitlockite-type structure Bioactive phosphates TCP Photoluminescence Rare earths

Antibacterial HA-coatings on bioresorbable mg alloy

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Journal of magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.v.Nadaraia D.v.m.shtalyar m.A.Piatkova A.I.Pleshkova I.m.Imshinetskiy m.S.Gerasimenko E.A.Belov v.v.Kumeiko D.N.Kozyrev K.A.Fomenko v.v.m.stovaya B.R.Torpanov A.R.Biktimirov I.S.Osmushko S.L.Sinebryukhov S.v.Gnedenkov Institute of Chemistry FEB RAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia Far Eastern Federal University 10 Ajax BayRussky IslandVladivostok 690922Russia A.v.Zhirmunsky National Scientific Center of marine Biology FEB RAS 17 St.PalchevskogoVladivostok 690041Russia Regional Clinical Dermatovenerological Dispensary 18 V St.GamarnikaVladivostok 690033Russia NmIC“Treatment and Rehabilitation Center” 3 Ivankovskoe highwayMoscow 125367Russia

In this study,a calcium-phosphate coating was formed on a mg-mn-Ce alloy by the plasma electrolytic oxidation(PEO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(***),was impregnated into the *** with vancomycin showed high bactericidal activity against *** mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were *** to SEm,EDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high *** analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the *** electrochemical tests,an increase in corrosion resistance by more than two times after the application of PEO coatings was *** to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by *** release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day *** the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility mg alloy Plasma electrolytic oxidation Hydroxyapatite vancomycin

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： D A Baghdasaryan v A Harutynyan E m Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Intertype superconductivity evoked by the interplay of disorder and multiple bands

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Frontiers of physics 2024年第4期19卷 81-89页

作者： P.m.marychev A.A.Shanenko A.v.vagov HSE University 101000 MoscowRussia Center for Advanced mesoscience and Nanotechnology MIPTDolgoprudny141700Russia

Nonmagnetic impurity scattering is known to shift up the Ginzburg-Landau parameter k of a *** this case,when the system is initially in type I,it can change its magnetic response,crossing the intertype domain with k~1 between the two standard superconductivity types and arriving at type *** the present work we demonstrate that the impact of disorder can be much more profound in the presence of the multiband structure of the charge carrier *** particular,when the band diffusivities differ from each other,the intertype domain tends to expand significantly,including points with k>>1 that belong to deep type-Ⅱ in conventional single-band *** finding sheds light on the nontrivial disorder effect and significantly complements earlier results on the enlargement of the intertype domain in clean multiband superconductors.

关键词： superconductivity disorder intertype superconductivity twoband model

Lithium:A review of applications,occurrence,exploration,extraction,recycling,analysis,and environmental impact

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Geoscience Frontiers 2024年第5期15卷 1-46页

作者： v.Balaram m.Santosh m.Satyanarayanan N.Srinivas Harish Gupta CSIR-National Geophysical Research Institute(NGRI) Hyderabad 500007India School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaide SA 5005Australia Department of Environmental Studies GITAM Institute of ScienceGandhi Institute of Technology&Management(GITAM)Visakhapatnam 530045India Department of Civil Engineering Osmania UniversityHyderabad 500007India

The energy transition challenges faced by modern civilization have significantly enhanced the demand for critical metals like lithium resulting in improved methods to explore,extract,and utilize these *** this comprehensive review,we discuss the different types of lithium resources,factors,and mechanisms controlling lithium enrichment in various geological settings including terrestrial and marine *** exploration strategies including geological,geophysical,mineralogical,geochemical,and remote sensing techniques including drone-based techniques for lithium exploration studies in different terranes are *** overview of the mining techniques,including beneficiation and extraction,and their principles,mechanisms,operations,and comparison of the various approaches and compatibility with different types of lithium deposits for obtaining maximum yield are *** isotopic studies are useful in understanding geological processes such as past weathering events and riverine input into the oceans,as well as in understanding the source of lithium in diverse types of *** also highlight the recent developments in other areas such as recycling,environmental impact,and state-of-the-art analytical techniques for determining lithium in different lithium ore deposits and other geological *** overview provides the latest developments and insights in the various sectors related to lithium and prompt further developments to meet the growing demand for this valuable metal as the world transforms to clean energy.

关键词： Lithium minerals Pegmatite Lithium brine deposits Lithium sedimentary deposits Exploration techniques

millimetric devices for nerve stimulation:a promising path towards miniaturization

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Neural Regeneration Research 2024年第8期19卷 1702-1706页

作者： Ryan m.Dorrian Anna v.Leonard Antonio Lauto Spinal Cord Injury Research Group School of BiomedicineThe University of AdelaideAdelaideSAAustralia School of Science Western Sydney UniversityPenrithNSWAustralia

Nerve stimulation is a rapidly developing field,demonstrating positive outcomes across several *** potential benefits,current nerve stimulation devices are large,complicated,and are powered via implanted pulse *** facto rs necessitate invasive surgical implantation and limit potential *** nerve stimulation devices to millimetric sizes would make these interventions less invasive and facilitate broader therapeutic ***,device miniaturization presents a serious engineering *** review presents significant advancements from several groups that have overcome this challenge and developed millimetricsized nerve stimulation *** are based on antennas,mini-coils,magneto-electric and optoelectronic materials,or receive ultrasound *** highlight key design elements,findings from pilot studies,and present several considerations for future applications of these devices.

关键词： biomedical engineering deep brain stimulation electrical engineering electrical stimulation neuromodulation peripheral nerve stimulation