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Arctic sea.i.e extent: No record minimum in 2023 or recent years

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Atmospheric and Ocea.i. Science Letters 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea.i.e extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correla.i.n between the long-term decrease in sea.i.e extent and the increa.i.g CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea.i.e in September, while the remainder is caused by natural va.i.bility.

关键词： Sea.i.e Arctic Minimum ice Climate

isometry Groups of Some Dunwoody Ma.i.olds

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Algebra Colloquium 2016年第1期23卷 117-128页

作者： F. Spaggia.i.a.i. Telloni Dipartimento di Matema.i.a Universit& di Modena e Reggio E. Via Campi 213/B 41100 Modena Italy

Dunwoody ma.i.olds are an interesting class of closed connected orientable 3-ma.i.olds, which are defined by means of Heegaard diagrams ha.i.g a rota.i.nal symmetry. They are proved to be cyclic coverings of lens spaces （possibly S3） branched over （1, 1）-knots. Here we study the Dunwoody ma.i.olds which are cyclic coverings of the 3-sphere branched over two specified fa.i.ies of Montesinos knots. Then we determine the Dunwoody parameters for such knots and the isometry groups for the considered ma.i.olds in the hyperbolic case. A list of volumes for some hyperbolic Dunwoody ma.i.olds completes the paper.

关键词： Dunwoody ma.i.old Montesinos knot branched covering isometry group

Coarse to Fine: The Role of Severe Plastic Deforma.i.n in Advancing Tita.i.m-Based Medical implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan i Međo ivana Lj Cvijović-Ala.i. Veljko R Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča.i.stitute of Nuclear Sci-ences-Na.i.nal institute of the Republic of Serbia University of Belgrade11001BeogradSerbia innova.i.n Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deforma.i.n(SPD)procedures,which are utilized to form an ultra.i.e-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deforma.i.n and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultra.i.e-grained tita.i.m-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,prima.i.y hydrosta.i. pressure,and number of revolutions during torsion,on the grain size and physical and mecha.i.al characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompa.i.ility of the tita.i.m-based biomaterials.A review of the literature indicates that tita.i.m-based materials obtained by the SPD process show improved mecha.i.al and physical properties without losing biocompa.i.ility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultra.i.e-grained tita.i.m-based materials electrochemical anodiza.i.n physical properties mecha.i.al properties

^(13)C NMR and structural study of solid state naphthol-1 and naphthol-2 arylazo-deriva.i.es

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Chinese Journal of Chemistry 1991年第3期9卷 245-250页

作者： FEDOROV L.A. REBROV a.i. REBROV a.i. institute of Geochemistry and Analytical Chemistry Academy of Sciences of USSR Institute of Geochemistry and Analytical ChemistryAcademy of Sciences of USSR

Solid state ^(13)C NMR spectra of a series of naphthol-1 and naphthol-2-arylazo--deriva- tives were studied and compared with respective results in *** of carbon nuclei of naphthalene ring were *** forms of compounds were *** was shown that 4-(p-NO_2C_6H_4)-azonaphthol-1 and 1-(p-NO_2C_6H_4)-azonaphthol-2 in solid state existed ex- clusively in quinohydrazone *** other two compounds——1-(C_6F_5)-azonaphthol-2 and 2-(p- CH_3C_6H_4)-azonaphthol-1 in solid state were not found in the form of individual tautomeric mixtures but in respective tautomeric equilibrium ***,during transition from liquid to solid state, the tautomeric equilibrium was practically *** solid state it was found that rota.i.n around aryl-N bond was hindered in the time scale of NMR spectroscopy.

关键词： C NMR and structural study of solid state naphthol-1 and naphthol-2 arylazo-deriva.i.es NMR

Multisensory mecha.i.ms of gait and balance in Parkinson’s disease:an integra.i.e review

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Neural Regenera.i.n Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico i.Bohnen Department of Ra.i.logy University of MichiganAnn ArborMIUSA Department of Neurology University of MichiganAnn ArborMIUSA Morris K.Udall Center of Excellence for Parkinson’s Disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia Department of Health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Founda.i.n Research Center of Excellence University of MichiganAnn ArborMIUSA Department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century transla.i.nal neuroscience due to the profound impact that falls and mobility disturbances have on our a.i.g *** and gait control does not happen automa.i.ally,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory informa.i.n,including visual,vestibular,and somatosensory *** mecha.i.ms which underpin the integra.i.n of these multisensory signals are the principal topic of the present *** multisensory integra.i.n theories focus on how failure of cognitive processes thought to be involved in multisensory integra.i.n leads to falls in older *** empha.i.,however,has been placed on specific contributions of individual sensory moda.i.ies to multisensory integra.i.n processes and cross-modal interactions that occur between the sensory moda.i.ies in rela.i.n to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular moda.i.ies,along with their multisensory intersections to gait and balance in older adults and pa.i.nts with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mecha.i.ms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography ima.i.g)and at the level of electrophysiology(concerning electroencephalography).We hope that this integra.i.e review,dra.i.g influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and pa.i.nts with neurodegenera.i.e diseases.

关键词： a.i.g balance encephalography functional magnetic resonance ima.i.g gait multisensory integra.i.n Parkinson’s disease positron emission tomography somatosensory vestibular visual

Screening the insecticidal Efficacy of Nano ZnO Synthesized via.i.-situ Polymeriza.i.n of Crosslinked Polyacrylic a.i. as a Template

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Journal of Materials Science & Technology 2012年第11期28卷 961-968页

作者： M. Mekewi Ahmed Shebl a.i. imam M.S. a.i. T. Albert Chemistry Department Faculty of Science Ain Shams University Plants Protection Department Desert Research Center

Nano zinc oxide （ZnO） is a very useful and important material in many industrial and biological applica.i.ns. in the present work, ZnO was synthesized by post thermal degrada.i.n of the precursor ＂zinc acetate di-hydrate＂ templated in crosslinked polyacrylic a.i. （PAA）. The crosslinked PAA template was prepared through an in-situ polymeriza.i.n process adopted in presence of ammonium per sulphate, as an initiator, and N, Nt- methylene bis-acryla.i.e as the crosslinker. Va.i.tion of prepara.i.n parameters and their impact on the oxide stoichiometry, crystal structure, crystallite size and surface texture of the oxide were investigated. Energy dispersive X-ray technique （EDX）, X-ray diffraction （XRD） and scanning electron microscopy （SEM） were convincingly used to reveal the oxide structural features and characteristics. The performed bioassay tests indicated the efficacy of this method of prepara.i.n to produce nano ZnO with novel insecticidal activity against the greater wax moth, Galleria rnellonella.

关键词： Nano ZnO in-situ polymeriza.i.n Polymer template insecticide Bioassay Galleria mellonella

Nano-Enhanced Dairy Scum Biodiesel Blends:Unleashing the Power of Aluminium Oxide for Sustainable and Efficient Engine Performance

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Journal of Thermal Science 2025年第1期34卷 283-302页

作者： Veeranna MODi Prasad B.RAMPURE Sunil Kumar SHETTY Madeva NAGARAL Channa Keshava NAiK N Johar MGM Muhammad irsyad ABDULLAH Abdullah i.AL-MANSOUR Shamshad ALAM KLE College of Engineering and Technology ChikodiVisvesvaraya Technological University Nitte (Deemed to be University) NMAM Institute of Technology (NMAMIT)Department of Mechanical Engineering Aircraft Research and Design Centre HAL Department of Mecha.i.al Engineering BGS College of Engineering and TechnologyBengaluruAffiliated to Visvesvaraya Technological University Management and Science University Department of Civil Engineering College of EngineeringKing Saud University

This study investigates the effect of aluminium oxide nanoparticlesaddition to biodiesel blends made from dairy milk scum on performance and combustion characteristics of the diesel *** dispersion of Al2O3nanoparticles in B20 blends at different concentra.i.ns was done with the help of *** number of blends were prepared for the *** Machine learning algorithms(Random Forest（RF）and CatBoost) was used for the *** results show that in compa.i.on to biodiesel blends without nanoparticles,the kinema.i. viscosity and density is higher for fuel blends with *** these Fuel blends have higher calorific *** blends exhibited reduced Brake Specific Fuel Consumption（BSFC） of2.85% than the blends without nano particles(Dairy Scum Methyl Ester Biodiesel 20%+Neat Diesel 80%（in volume）,DSMEB20),57.14% less CO,40.8% less hydrocarbon,and increased NOxemissions compared to conventional diesel,contributing to the development of environmentally friendly and renewable biofuel blends with *** B20NP30 is the optimal blend for performance and emission *** study concludes with findings on enhanced Brake Thermal Efficiency（BTE） of 26.29% in 3×10-5（in volume） Al2O3nanoparticle-blended DSME B20 and other DSME B20 fuel blends,empha.i.ing the importance of optimal nanoparticle *** correla.i.n matrix shows how engine load,efficiency measures（BTE,BSFC）,and emissions（CO,CO2,NOx,Smoke） are connected in complex *** results help us understand the complicated dyna.i.s of engine performance and emission characteristics ***'s diagram for BTE and BSFC shows that CatBoost-based BTE models perform superior to RF-based models during the training as well as testing *** results were obtained for CO and CO2emission results.

关键词： Al2O3 concentra.i.n Ci engine Dairy Scum Methyl Ester Biodiesel

Reduction of the residual stresses in cold expanded thick-walled cylinders by plastic compression

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Defence Technology（防务技术） 2016年第6期12卷 473-479页

作者： V.F. SKVORTSOV A.O. BOZNAK A.B. KiM A. Yu ARLYAPOV a.i. DMiTRiEV Department of Automated Engineering Technology Tomsk Polytechnic University Lenin Av. 30 Tomsk Russia institute of Strength Physics and Materials Science SB RAS Akademicheski 2/4 Tomsk Russia

We suppose that in order to maintain high accuracy of holes and to lower residual stresses after cold expansion of thick-walled cylinders, which undergo cross-section plastic deforma.i.n, it is necessary to perform a.i.l plastic compression and subsequent cold expansion with small interferences. To test this hypothesis, we studied hoop, ra.i.l and a.i.l residual stresses in cylinders made of carbon steel AiSi 1050 with hole diameter of 5 mm, outer diameter of 15 mm and length of 30 mm by Sachs method as well as accuracy of expanded holes. it is found that double cold expansion with total interference equal to 5.1% generates hoop residual stresses with largest absolute value equal to 284 MPa and ensures high holes accuracy(iT7). After plastic compression with strain equal to 0.5 and 1% the mentioned stresses reduced to 120 and 75 MPa respectively,and accuracy of the holes reduced as well. Subsequent cold expansion with small interference equal to 0.9% helps to restore holes accuracy(iT7)gained by double cold expansion and ensure that absolute value of hoop residual stresses(177 MPa) is lower compared to double cold expansion.

关键词： Thick-walled cylinders Cold expansion Plastic compression Residual stresses

Effects of small additions of Zn on the microstructure, mecha.i.al properties and corrosion resistance of WE43B Mg alloys

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interna.i.nal Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 858-868页

作者： A.V. Koltygin V.E. Bazhenov R.S. Khasenova A.A. Komissarov a.i. Bazlov V.A. Bautin Foundry Department National University of Science and Technology “MISiS” Moscow 119049 Russia Laboratory of Hybrid Nanostructured Materials National University of Science and Technology “MISiS” Moscow 119049 Russia Laboratory of Advanced Green Materials National University of Science and Technology “MISiS” Moscow 119049 Russia Department of Metallurgy Steel New Production Technologies and Protection of Metals National University of Science and Technology “MISiS” Moscow 119049 Russia

Zn is a commonly used alloying element for Mg alloys owing to its beneficial effects on mecha.i.al properties. To improve the mecha.i.al and corrosion properties of WE43B Mg alloys, the effects of 0–0.7wt% Zn addition on the microstructure and properties of sample alloys were investigated. Addition of Zn to as-cast WE43B alloy promoted the forma.i.n of the Mg12Nd phase;by contrast, after T6 heat treatment, the phase composition of WE43B alloys with and without Zn addition remained mostly the same. A long-period stacking ordered phase was predicted by CALPHAD calcula.i.n, but this phase was not observed in either the as-cast or heat-treated Zn-containing WE43B alloys. The optimum temperature and dura.i.n of T6 heat treatment were obtained using CALPHAD calcula.i.ns and hardness measurements. Addition of Zn resulted in a slight reduction in the average grain size of the as-cast and T6 heat-treated WE43B alloys and endowed them with increased corrosion resistance with little effect on their mecha.i.al properties.

关键词： magnesium alloys corrosion resistance mecha.i.al properties Zn addition