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Phase preservation of orbital angular momentum of light in multiple scattering environment

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Light(Science & Applications) 2024年第10期13卷 2263-2275页

作者： Igor Meglinski ivan Lopushenko Anton Sdobnov Alexander Bykov College of Engineering and Physical Sciences Aston UniversityBirmingham B47ETUK Optoelectronics and Measurement Techniques University of OuluOulu FI-90014Finland

Recent advancements in wavefront shaping techniques have facilitated the study of complex structured light’s propagation with orbital angular momentum(OAM)within various *** introduction of spiral phase modulation to the Laguerre–Gaussian(LG)beam during its paraxial propagation is facilitated by the negative gradient of the medium’s refractive index change over time,leading to a notable increase in the rate of phase twist,effectively observed as phase retardation of the *** approach attains remarkable sensitivity to even the slightest variations in the medium’s refractive index(∼10−6).The phase memory of OAM is revealed as the ability of twisted light to preserve the initial helical phase even propagating through the turbid tissue-like multiple scattering *** results confirm fascinating opportunities for exploiting OAM light in biomedical applications,*** as non-invasive trans-cutaneous glucose diagnosis and optical communication through biological tissues and other optically dense media.

关键词： scattering momentum light

Applying the Shearlet-Based Complexity Measure for Analyzing Mass Transfer in Continuous-Flow Microchannels

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Fluid Dynamics & Materials Processing 2024年第8期20卷 1743-1758页

作者： Elena Mosheva ivan Krasnyakov Institute of Continuous Media Mechanics UB RAS Perm614013Russia Department of Applied Physics Perm National Research Polytechnic UniversityPerm614990Russia

Continuous-flow microchannels are widely employed for synthesizing various materials,including nanoparticles,polymers,and metal-organic frameworks(MOFs),to name a *** technology allows precise control over reaction parameters,resulting in purer,more uniform,and structurally stable products due to more effective mass transfer ***,continuous-flow synthesis processes may be accompanied by the emergence of spatial convective structures initiating convective *** the one hand,convection can accelerate reactions by intensifying mass *** the other hand,it may lead to non-uniformity in the final product or defects,especially in MOF microcrystal *** ability to distinguish regions of convective and diffusive mass transfer may be the key to performing higher-quality reactions and obtaining purer *** this study,we investigate,for the first time,the possibility of using the information complexity measure as a criterion for assessing the intensity of mass transfer in microchannels,considering both spatial and temporal non-uniformities of liquid’s distributions resulting from convection *** calculate the complexity using shearlet transform based on a local *** contrast to existing methods for calculating complexity,the shearlet transform based approach provides a more detailed representation of local *** analysis involves experimental images illustrating the mixing process of two non-reactive liquids in a Y-type continuous-flow microchannel under conditions of double-diffusive convection *** obtained complexity fields characterize the mixing process and structure formation,revealing variations in mass transfer intensity along the *** compare the results with cases of liquid mixing via a pure diffusive *** analysis,it was revealed that the complexity measure exhibits sensitivity to variations in the type of mass transfer,establishing its feasibility as an ind

关键词： Shearlet analysis complexity measure entropy measure convection microchannels double-diffusive instability

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

A theoretical justification of the slip index concept in fretting analysis

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Friction 2023年第7期11卷 1265-1275页

作者： ivan I.ARGATOV Young S.CHAI Institut für Mechanik Technische Universität Berlin10623 BerlinGermany School of Mechanical Engineering Yeungnam UniversityGyeongsan 712-749Republic of Korea

Fretting in the partial-slip and gross-slip regimes under a constant normal load is *** tangential force-displacement relations for the forward and backward motions are described based the generalized Cattaneo-Mindlin theory of tangential contact and Masing's hypothesis on modelling the force-displacement hysteretic *** the critical force and displacement parameters(characterizing the triggering of sliding),the model includes one dimensionless fitting parameter that tunes the tangential contact stiffness of the friction-contact *** expressions are derived for the main tribological parameters of the fretting loop,including the slip index and the signal *** presented phenomenological modelling approach has been applied to the analysis of two sets of experimental data taken from the *** has been shown that the experimentally observed simple relation of a rational type between the slip index and the slip ratio corresponds to the gross-slip asymptotics of the corresponding model-based predicted *** known quantitative criteria for the transition from the partial slip regime to the gross slip regime are expressed in terms of the stiffness parameter,and a novel geometric transition criterion is formulated.

关键词： fretting wear slip index signal index partial slip energy ratio

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

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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

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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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