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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

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 ... 详细信息

关键词： ELECTROLYTE

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

COVID-19 and Ecosyndemic Vulnerability: Implications for El Niño-Sensitive Countries in Latin America

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International Journal of Disaster Risk Science 2021年第1期12卷 147-156页

作者： ivan J.Ramírez Jieun Lee Department of Health and Behavioral Sciences University of Colorado DenverDenverCO 80217USA Consortium for Capacity Building Institute of Arctic and Alpine Research(INSTAAR)University of Colorado BoulderBoulderCO 80308USA Department of Geography GISand SustainabilityUniversity of Northern ColoradoGreeleyCO 80639USA

Latin America has emerged as an epicenter of the COVID-19 ***,Peru,and Ecuador report some of the highest COVID-19 rates of incidence and deaths in the *** countries also face synergistic threats from multiple infectious diseases(that is,ecosyndemic)and quasi-periodic El Niño-related hazards every few *** example,Peru,which is highly sensitive to El Niño,already copes with an ecosyndemic health burden that heightens during and following weather and climate extreme *** an ecosyndemic lens,which draws on a multi-disease hazard context of place,this commentary highlights the importance of El Niño as a major factor that not only may aggravate COVID-19 incidence in the future,but also the broader health problem of ecosyndemic vulnerability in Latin America.

关键词： Coronavirus COVID-19 Ecosyndemic El Niño El Niño-Southern oscillation Infectious disease vulnerability Latin America

Solar flares with similar soft but different hard X-ray emissions： case and statistical studies

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Research in Astronomy and Astrophysics 2016年第1期16卷 39-50页

作者： ivan N.Sharykin Alexei B.Struminsky ivan V.Zimovets Wei-Qun Gan Space Research Institute Russian Academy of Sciences Moscow 117997 Russia Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

From the Reuven Ramaty High Energy Solar Spectroscopic Imager （RHESS1） catalog we select events which have approximately the same GOES class （high C - low M or 500-1200 counts s-1 within the RHESSI 6-12 keV energy band）, but with different maximal energies of detected hard X-rays. The selected events are subdivided into two groups：（1） flares with X-ray emissions observed by RHESSI up to only 50 keV and （2） flares with hard X-ray emission observed also above 50 keV. The main task is to understand observational peculiarities of these two flare groups. We use RHESSIX-ray data to obtain spectral and spa- tial information in order to find differences between selected groups. Spectra and images are analyzed in detail for six events （case study）. For a larger number of samples （85 and 28 flares in the low-energy and high-energy groups respectively） we only make some generalizations. In spectral analysis we use the thick- target model for hard X-ray emission and one temperature assumption for thermal soft X-ray emission. RHESSI X-ray images are used for determination of flare region sizes. Although thermal and spatial prop- erties of these two groups of flares are not easily distinguishable, power law indices of hard X-rays show significant differences. Events from the high-energy group generally have a harder spectrum. Therefore, the efficiency of chromospheric evaporation is not sensitive to the hardness of nonthermal electron spectra but rather depends on the total energy flux of nonthermal electrons.

关键词： Sun: flares -- Sun: X-rays -- gamma rays

A Markov chain model of mixing kinetics for ternary mixture of dissimilar particulate solids

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Particuology 2017年第2期15卷 80-86页

作者： Vadim Mizonov ivan Balagurov Henri Berthiaux Cendrine Gatumel Department of Applied Mathematics Ivanovo State Power Engineering University Russia Centre RAPSODEE UMR CNRS 5302 Ecole des Mines d'Albi-Carmaux Campus Jarlard Route de Teillet 81000 Alhi France

This paper presents a simple but informative mathematical model to describe the mixing of three dissimilar components of particulate solids that have the tendency to segregate within one another. A nonlinear Markov chain model is proposed to describe the process. At each time step, the exchange of particulate solids between the cells of the chain is divided into two virtual stages. The first is pure stochastic mixing accompanied by downward segregation. Upon the completion of this stage, some of the cells appear to be overfilled with the mixture, while others appear to have a void space. The second stage is related to upward segregation. Components from the overfilled cells fill the upper cells （those with the void space） according to the proposed algorithm. The degree of non-homogeneity in the mixture （the standard deviation） is calculated at each time step, which allows the mixing kinetics to be described. The optimum mixing time is found to provide the maximum homogeneity in the ternary mixture. However, this “common” time differs from the optimum mixing times for individual components. The model is verified using a lab-scale vibration vessel, and a reasonable correlation between the calculated and experimental data is obtained

关键词： Ternary mixture Segregation Mixing kinetics Markov chain Matrix of transition probabilities Optimum mixing time

Weighted Sum of Gray Gases Model Optimization for Numerical Investigations of Processes inside Pulverized Coal-Fired Furnaces

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Journal of Thermal Science 2017年第6期26卷 552-559页

作者： Nenad Crnomarkovic Srdjan Belosevic ivan Tomanovic Aleksandar Milicevic University of Belgrade Vinea Institute of Nuclear Sciences P. O. Box 522 11001 Belgrade Serbia

The effects of the number of significant figures （NSF） in the interpolation polynomial coefficients （IPCs） of the weighted sum of gray gases model （WSGM） on results of numerical investigations and WSGM optimization were investigated. The investigation was conducted using numerical simulations of the processes inside a pulverized coal-fired furnace. The radiative properties of the gas phase were determined using the simple gray gas model （SG）, two-term WSGM （W2）, and three-term WSGM （W3）. Ten sets of the IPCs with the same NSF were formcd for every weighting coefficient in both W2 and W3. The average and maximal relative difference values of the flame temperatures, wall temperatures, and wall heat fluxes were determined. The investigation showed that the results of numerical investigations were affected by the NSF unless it exceeded certain value. The increase in the NSF did not necessarily lead to WSGM optimization. The combination of the NSF （CNSF） was the necessary requirement for WSGM optimization.

关键词： Furnace Numerical simulation Significant figure Weighted sum of gray gases model Optimization