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Liquid superlubricity of lubricants containing hydroxyl groups and their aqueous solution under rolling/sliding conditions

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Friction 2024年第1期12卷 164-173页

作者： Tomáš POLÁČEK Petr ŠPERKA ivan KŘUPKA Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic

Macroscale rolling/sliding conditions are in the superlubricity,a little-studied topic so *** purpose of this paper is to examine the formation of elastohydrodynamic lubrication(EHL)films by water-based lubricants(glycerol and polyethylene glycol(PEG)),providing superlubricous *** were carried out on an optical ball-on-disc tribometer under rolling/sliding *** film thickness was measured by the thin film colorimetric interferometry,and the viscosity of liquids was measured by rotational and high-pressure falling body *** results show that tribochemical reactions are not the mandatory reason for friction to reach the superlubricity level when using the water-based *** studied liquids themselves are almost *** the addition of water,the signs of shear thinning behavior disappear even *** conditions for this type of lubricant can be predicted using the known Hamrock–Dowson *** anomaly in the thickness of the lubricants was observed as an abrupt change at certain *** more PEG there is in the lubricant,the higher the thickness at the beginning of the jump.

关键词： macroscale superlubricity super low traction water-based lubricants elastohydrodynamic lubrication(EHL) film thickness

Simple experimental procedures to distinguish photothermal from hot-carrier processes in plasmonics

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Light(Science & Applications) 2020年第1期9卷 974-989页

作者： Guillaume Baffou ivan Bordacchini Andrea Baldi Romain Quidant Institut Fresnel CNRSAix Marseille UniversityCentrale MarseilleMarseilleFrance ICFO-Institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology08860CastelldefelsBarcelonaSpain DIFFER-Dutch Institute for Fundamental Energy Research De Zaale 205612 AJ EindhovenThe Netherlands Vrije Universiteit Amsterdam De Boelelaan 10811081 HV AmsterdamThe Netherlands ICREA-Institucio Catalana de Recerca i Estudis Avancats 08010 BarcelonaSpain Nanophotonic Systems Laboratory Department of Mechanical and Process EngineeringETH Zurich8092ZurichSwitzerland

Light absorption and scattering of plasmonic metal nanoparticles can lead to non-equilibrium charge carriers,intense electromagnetic near-fields,and heat generation,with promising applications in a vast range of fields,from chemical and physical sensing to nanomedicine and photocatalysis for the sustainable production of fuels and *** the relative contribution of thermal and non-thermal contributions in plasmon-driven processes is,however,*** temperature measurements are technically challenging,and macroscale experiments are often characterized by collective heating effects,which tend to make the actual temperature increase *** work is intended to help the reader experimentally detect and quantify photothermal effects in plasmon-driven chemical reactions,to discriminate their contribution from that due to photochemical processes and to cast a critical eye on the current *** this aim,we review,and in some cases propose,seven simple experimental procedures that do not require the use of complex or expensive thermal microscopy *** proposed procedures are adaptable to a wide range of experiments and fields of research where photothermal effects need to be assessed,such as plasmonic-assisted chemistry,heterogeneous catalysis,photovoltaics,biosensing,and enhanced molecular spectroscopy.

关键词： collective photochemical intense

Farinose fiavonoids are associated with high freezing tolerance in fairy primrose (Primula malacoides) plants

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Journal of Integrative Plant Biology 2014年第2期56卷 181-188页

作者： Ryutaro Isshiki ivan Galis Shigemi Tanakamaru Institute of Plant Science and Resources Okayama University

The deposition of surface （farinose） flavonoids on aerial parts of some Primula species is a well-documented but poorly understood phenomenon. Here, we show that flavonoid deposition on the leaves and winter buds may contribute strongly to preventing freezing damage in these plants. The ice nucleation temperature of fairy primrose （Primula malacoides） leaves covered with natural flavone was approximately 6~C lower compared to those that had their flavone artificially removed. Additionally, farinose flavonoids on the leaves reduced subse- quent electrolyte leakage （EL） from the cells exposed to freezing temperatures. Interestingly, exogenous application of flavone at 4 mg/g fresh weight to P. malacoides leaves, which had the original flavone mechanically removed, restored freezing tolerance, and diminished EL from the cells to pretreatment values. Our results suggest that farinose flavonoids may function as mediators of freezing tolerance in P. malacoides, and exogenous application of flavone could be used to reduce freezing damage during sudden but predictable frost events in other plant species.

关键词： Flavonoids freezing tolerance ice nucleation temperature plant protection

In-hole velocity of detonation(VOD) measurements as a framework for the selection type of explosive

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International Journal of Mining Science and Technology 2015年第4期25卷 675-680页

作者： Mesec Josip Zganec Stjepan Kova ivan University of Zagreb Geotechnical Faculty in Varazdin Minervo d.d.

Velocity of detonation （VOD） is one of the most important properties of explosives and indicates perfor- mances of explosives in real time. With the development of blast monitoring systems, continuous VOD monitoring systems are recently available. The VOD measurement in holes helps in comparing and eval- uating relative performances of explosives. The purpose of this paper is a framework for selecting the type of explosives. This paper analyses the results of VOD measurements, carried out at the limestone quarry （Zrnotiti （~~rni kal）, Slovenia. Experiments were conducted to measure VOD in blast holes which were loaded with ANFO, heavy ANFO and emulsion explosives. The explosives are produced at the point of use with mobile equipment. In this study, resistance wire continuous VOD measurement system MicroTrap, VODSYS-4 from MREL was used and framework for selection the type of explosives has been suggested.

关键词： Explosives Velocity Detonation VOD In-hole measurements

Bright trions in direct-bandgap silicon nanocrystals revealed by low-temperature single-nanocrystal spectroscopy

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Light(Science & Applications) 2015年第1期4卷 179-186页

作者： Katerina Kusova ivan Pelant Jan Valenta Institute of Physics of the ASCR v.v.i.Cukrovarnicka 1016200 Prague 6Czech Republic Faculty of Mathematics and Physics Charles UniversityKe Karlovu 512116 Prague 2Czech Republic

Strain-engineered silicon nanocrystals(SiNCs)have recently been shown to possess direct ***,we report the observation of a rich structure in the single-nanocrystal photoluminescence spectra of strain-engineered direct-bandgap SiNCs in the temperature range of 9–300 *** relationship between individual types of spectra is discussed,and the numerical modeling of spectral diffusion of the experimentally acquired spectra reveals a common origin for most *** intrinsic spectral shape is shown to be a structure that contains three peaks,approximately 150 meV apart,each of which possesses a Si phonon *** spectral lines,reaching ≤ meV at 20 K,are *** observed temperature dependence of the spectral structure can be assigned to the radiative recombination of positively charged trions,in contrast to several previous reports linking a very similar shape to phonons in the surface capping *** result serves as strong additional support for the direct-bandgap nature of the investigated SiNCs.

关键词： direct bandgap low-temperature single-nanocrystal spectroscopy silicon nanocrystals trions

Sustainable and biocompatible Zn-based batteries

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National Science Review 2023年第4期10卷 8-9页

作者： Guanjie He ivan P.Parkin Department of Chemical Engineering University College London Christopher Ingold Laboratory Department of Chemistry University College London

Next-generation and functional batery technologies beyond the Li-ion are emerging [1]. Sustainable and biocompatible bateries are needed for certain applications, including implantable medical devices [2]. Zinc-based bateries(ZBs) are encouraging technologies with low cost, high theoretical capacity and high safety features [3].

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Biogenic Amorphous Silica as Filler for Elastomers

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Journal of Renewable Materials 2018年第4期6卷 402-412页

作者： Nikolay Dishovsky Petrunka Malinova ivan Uzunov University of Chemical Technology and Metallurgy-Sofia 8 St.Kliment Ohridski Blv.1756 SofiaBulgaria Institute of General and Inorganic Chemistry Bulgarian Academy of SciencesAcad.G.Bonchev Str.bl.111113 SofiaBulgaria

Natural products from agricultural wastes are finding importance in the polymer industry due to their many advantages such as being lightweight,low cost and environmentally *** the present study the potential of the two types of rice husk ash(RHA)prepared under different conditions as fillers in natural rubber-based elastomer composites was *** fillers were prepared by rice husks incineration and characterized by means of X-ray powder diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),scanning electron microscope(SEM),Brunauer-Emmett-Teller(BET)specific surface area,Hg-porosimetry and *** evaluation involved determining the vulcanization characteristics of the compounds and their physical and mechanical characteristics,resistance to thermal aging as well as the dynamic properties of the vulcanizates containing *** has been found that the ash from rice husk has good potential as filler in elastomers,especially as a substitute for synthetic commercially available *** improves the grip on ice and snow better than standard silica and may be used in formulations for shoe soles used for winter sports,extreme hiking footwear,ski boot soles,winter tire protectors,*** quality depends on the conditions under which rice husk is *** is recommended to run the process at a temperature not higher than 800°*** particular,cases in which the vulcanizates contain biogenic silica have very interesting characteristics like improved modulus at 300%of elongation,lower residual elongation,higher mechanical loss angle tangent at 0°C and lower at 60°C,and are superior to those of the vulcanizates containing commercially available filler Ultrasil?7000 GR.

关键词： Rice husk ash fillers natural rubber mechanical characteristics dynamic properties

A Stein deficit for the logarithmic Sobolev inequality

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Science China Mathematics 2017年第7期60卷 1163-1180页

作者： LEDOUX Michel NOURDIN ivan PECCATI Giovanni Institut de Mathematiques de Toulouse Universite de Toulouse-Paul-Sabatier Toulouse F-31062 France Institut Universitaire de France UR en Mathematiques-FSTC Luxembourg University Luxembourg City L-1359 Luxembourg

We provide some lower bounds on the deficit in the Gaussian logarithmic Sobolev inequality in terms of the so-called Stein characterization of the Gaussian *** techniques are based on the representation of the relative Fisher information along the Ornstein-Uhlenbeck semigroup by the Minimum Mean-Square Error from information theory.

关键词： deficit logarithmic Sobolev inequality Ornstein-Uhlenbeck semigroup minimum mean-square error Stein kernel

Pre-trained Mol2Vec Embeddings as a Tool for Predicting Polymer Properties

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Chinese Journal of Polymer Science 2024年第12期42卷 2059-2068,I0014页

作者： ivan Zlobin Nikita Toroptsev Gleb Averochkin Alexander Pavlov Center NTI“Digital Materials Science:New Materials and Substances” Bauman Moscow State Technical University2S1 Baumanskaya St.5/1105005MoscowRussia A.N.Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences Vavilova St.28Bld.1119334MoscowRussia

Machine learning-assisted prediction of polymer properties prior to synthesis has the potential to significantly accelerate the discovery and development of new polymer *** date,several approaches have been implemented to represent the chemical structure in machine learning models,among which Mol2Vec embeddings have attracted considerable attention in the cheminformatics community since their introduction in ***,for small datasets,the use of chemical structure representations typically increases the dimensionality of the input dataset,resulting in a decrease in model ***,the limited diversity of polymer chemical structures hinders the training of reliable embeddings,necessitating complex task-specific architecture *** address these challenges,we examined the efficacy of Mol2Vec pre-trained embeddings in deriving vectorized representations of *** study assesses the impact of incorporating Mol2Vec compound vectors into the input features on the efficacy of a model reliant on the physical properties of 214 *** results will hopefully highlight the potential for improving prediction accuracy in polymer studies by incorporating pre-trained embeddings or promote their utilization when dealing with modestly sized polymer databases.

关键词： Properties prediction High dimensional embeddings Machine learning Mol2Vec