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Fuel characteristics, loads and consumption in Scots pine forests of central Siberia

Journal of Forestry Research 2020年第6期31卷 2507-2524页

作者： Galina A.Ivanova Elena A.Kukavskaya valery A.Ivanov Susan G.Conard Douglas J.McRae v.N.sukachev institute of forest sb ras-separate subdivision of the federal research center“krasnoyarsk science center of the siberian branch of the russian academy of sciences” krasnoyarskrussia 660036 M.F.reshetnev siberian state university of science and technology krasnoyarskrussia 660049 Emeritus scientist rocky mountain research stationu.s.forest servicemissoulamt 59807usa George mason university fairfaxvausa Canadian forest service natural resources canada1219 queen street eastsault st5.marieon p6a 2e5canada

Forest fuel investigations in central and southern Siberian taiga of Scots pine forest stands dominated by lichen and feather moss ground vegetation cover revealed that total aboveground biomass varied from 13.1 to 21.0 kg/m *** biomass was higher in plots in the southern taiga,while ground fuel loads were higher in the central *** developed equations for fuel biomass(both aerial and ground)that could be applicable to similar pine forest sites of Central *** loading variability found among plots is related to the impact and recovery time since the last wildfi re and the mosaic distribution of living *** consumption due to surface fi res of low to high-intensities ranged from 0.95 to 3.08 kg/m 2,that is,18–74%from prefi re *** total amount of fuels available to burn in case of fi re was up to 4.5–6.5 kg/m *** content of fuels(litter,lichen,feather moss)was related to weather conditions characterized by the Russian Fire Danger Index(Pv-1)and FWI code of the Canadian Forest Fire Weather Index *** data obtained provide a strong foundation for understanding and modeling fi re behavior,emissions,and fi re eff ects on ecosystem processes and carbon stocks and could be used to improve existing global and regional models that incorporate biomass and fuel characteristics.

关键词： Pinus sylvestris Tree biomass Surface and ground fuel loads Fuel moisture Fuel consumption

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The Distribution and Substrate Specificity of Extracellular Nuclease Activity in Marine Fungi

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Open Journal of Marine Science 2012年第4期2卷 188-195页

作者： Larissa A. Balabanova Michael v. Pivkin valery A. Rasskazov G.B. Elyakova Pacific Institute of Bioorganic Chemistry Far-Eastern Branch of Russian Academy of Sciences Vladivostok Russia

The distribution and specificity of extracellular nucleases produced by marine fungi belonging to eleven genera, namely: Alternaria, Aspergillus, Aureobasidium, Chaetomium, Fusarium, Gliomastix, Humicola, Penicillium, Scopulariopsis, Wardomyces, Periconia, have implied its important function in the organic phosphorus and nitrogen circle in the Ocean. The fungal nucleases of 64 isolates tested were more or less specific for single-stranded DNA with a high preferential specificity towards poly-U substrate with forming of 5’-phosphate mononucleotides. A couple of the nucleases were capable of RNA digesting. The highest level of extracellular nucleolytic ability was observed in Penicillium spp. isolates. The tight correlation found between extracellular nuclease activity and the rate of thymidine uptake by actively growing and sporulating marine fungus Penicillium melinii suggests that this nuclease is required for fulfilling the nucleotide pool of precursors of DNA biosynthesis during transformation of hyphae into the aerial mycelium and conidia in stressful environmental conditions.

关键词： Marine Fungi Marine Environment Single-Strand-Specific Nuclease DNAse RNAse ssDNA Thymidine Uptake

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Antibiotics,gut microbiota,and irritable bowel syndrome:What are the relations?

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World Journal of Gastroenterology 2022年第12期28卷 1204-1219页

作者： Zarina Mamieva Elena Poluektova valery Svistushkin vasily Sobolev Oleg Shifrin Francisco Guarner vladimir Ivashkin Department of Internal Disease Propaedeutics N.V.Sklifosovsky Institute of Clinical MedicineI.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991Russia Department of Ear Throat and Nose DiseasesN.V.Sklifosovsky Institute of Clinical MedicineI.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991Russia Digestive System Research Unit Vall d’Hebron Research InstituteBarcelona 08035Spain

Irritable bowel syndrome(IBS)is a functional gastrointestinal disorder in which recurrent abdominal pain is associated with defecation or a change in bowel habits(constipation,diarrhea,or both),and it is often accompanied by symptoms of abdominal bloating and *** is an important health care issue because it negatively affects the quality of life of patients and places a considerable financial burden on health care *** extensive research,the etiology and underlying pathophysiology of IBS remain incompletely *** mechanisms involved in its pathogenesis include increased intestinal permeability,changes in the immune system,visceral hypersensitivity,impaired gut motility,and emotional ***,accumulating evidence has highlighted the important role of the gut microbiota in the development of *** dysbiosis within the gut is thought to contribute to all aspects of its multifactorial *** last few decades have also seen an increasing interest in the impact of antibiotics on the gut ***,antibiotics have been suggested to play a role in the development of *** research has established that antibacterial therapy induces remarkable shifts in the bacterial community composition that are quite similar to those observed in *** suggestion is further supported by data from cohort and case-control studies,indicating that antibiotic treatment is associated with an increased risk of *** paper summarizes the main findings on this issue and contributes to a deeper understanding of the link between antibiotic use and the development of IBS.

关键词： Gut microbiota Irritable bowel syndrome Antibiotics Intestinal barrier Gut motility Gut sensitivity

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Nitroxy-and azidomethyl azofurazans as advanced energetic materials

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Defence Technology（防务技术） 2022年第8期18卷 1369-1381页

作者： Aleksei B.Sheremetev Svetlana F.Mel'nikova Elizaveta S.Kokareva Ruslan E.Nekrutenko Kirill v.Strizhenko Kyrill Yu Suponitsky Thanh Dat Pham Alla N.Pivkina valery P.Sinditskii Zelinsky Institute of Organic Chemistry Russian Academy of Sciences47 Leninsky ProspMoscow119991Russia Saint Petersburg State Institute of Technology 26 Moskovskii PrSt Petersburg190013Russia Mendeleev University of Chemical Technology Moscow125047Russia N.N.Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences4 Kosygina Str119991MoscowRussia

Progress in the rocket industry is only possible on the basis of new, higher performance and more environmentally friendly materials compared to up-to-date propellant ingredients for liquid, solid, gelled and hybrid propellant systems. In this work, synthetic methods have been developed for the preparation of new energetic azofurazans bearing nitroxymethyl or azidomethyl groups. All prepared compounds were fully characterized by multinuclear NMR and IR spectroscopies, as well as elemental analyses. An analysis of the structural features based on the X-ray single-crystal diffraction made it possible to discuss their influence on the densities of the azofurazans of this study. Thermal decomposition and combustion of nitroxymethyl and azidomethyl azofurazans were studied using a number of complementary experimental techniques, namely thermogravimetry, differential scanning calorimetry, manometry, microthermocouple measurements in the combustion wave. The structural and physical characteristics of these new energetic analogues illustrate the extent to which the nature of the explosophoric groups can be used to tune the performace of the azofurazan framework. These azofurazans possess positive calculated enthalpy of formation and are promising candidates for new environmentally friendly energetic materials.

关键词： Azofurazan Azide Nitrate ester X-ray Combustion

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Self-Assembly and Ordering of C60 on the WO2/W（110） Surface

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Nano Research 2011年第2期4卷 194-203页

作者： Sergey A. Krasnikov Sergey I. Bozhko Kevin Radican Olaf Lübben Barry E. Murphy Sundar-Raja vadapoo Han-Chun Wu Mohamed Abid valery N. Semenov lgor v. Shvets Centre tbr Research on Adaptive Nanostrucmres and Nanodevices （CRANN） School of Physics Trinity College Dublin Dublin 2 Ireland Institute of Solid State Physics Russian Academy of Sciences Chernogolovka Russian Federation King Abdullah Institute for Nanoteclmology College of Science King Saud University Riyadh 1145l Saudi Arabia

The growth and ordering of C60 molecules on the WO2/W（110） surface have been studied by low-temperature scanning tunnelling microscopy and spectroscopy （STM and STS）, low-energy electron diffraction （LEED）, and density functional theory （DFT） calculations. The results indicate the growth of a well-ordered C60 layer on the WO2/W（110） surface in which the molecules form a close-packed hexagonal structure with a unit cell parameter equal to 0.95 nm. The nucleation of the C60 layer starts at the substrate＇s inner step edges. Low-temperature STM of C60 molecules performed at 78 K demonstrates well-resolved molecular orbitals within individual molecules. In the C60 monolayer on the WO2/W（110） surface, the molecules are aligned in one direction due to intermolecular interaction, as shown by the ordered molecular orbitals of individual C60. STS data obtained from the C60 monolayer on the WO2/W（110） surface are in good agreement with DFT calculations.

关键词： Fullerenes self-assembly tungsten oxide low-temperature scanning tunnelling microscopy scanning tunnellingspectroscopy W(110)

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Chaotic approach in biomedicine: Individualized medical treatment

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Journal of Biomedical Science and Engineering 2013年第8期6卷 847-853页

作者： valery M. Eskov Alexander A. Khadartsev valery v. Eskov Olga E. Filatova Diana U. Filatova Institute of Techniques and Natural Sciences Surgut State University Surgut Russia

According to classic deterministic-stochastic approaches, we don’t have any possibility for realization of the basic principle in medicine because every human organism has its own specific features. It is evident for us that requirement of medical personification includes two procedures: individual (with uninterrupted procedure of human organism state measurement) diagnostics and the second part which is connected with uninterrupted control of the efficiency of medical treatment and measurements of human organism parameters. We conduct the diagnostics according to behavior of state vector of human organism in phase space of states according to every coordinates of human’s state vector and with calculation of quasiattractors. We can present the results of our observations: what may be good for one person is not necessarily good for another. We present new bioinformational methods and software for calculation of quasiattractors parameters for dissolving such contradictions between deterministic-stochastic medicine and the use of theory of chaos self-organization where the state vector of human organism demonstrates uninterrupted movements. The practical results of such procedure are also presented according to the theory of chaos-self-organization. So there are great distinctions between the classic deterministic-stochastic approach (based on traditional medicine requirements) and the new theory of chaos self-organization which considers every human organism as a unique system with individual properties.

关键词： Personification Phase Space State vector Attractor Complexity Chaos Self-Organization Medicine

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Phase-matched third-harmonic generation via doubly resonant optical surface modes in 1D photonic crystals

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Light(Science & Applications) 2016年第1期5卷 424-429页

作者： valery N Konopsky Elena v Alieva Sergey Yu Alyatkin Alexey A Melnikov Sergey v Chekalin vladimir M Agranovich Institute of Spectroscopy Fizicheskaya5TroitskMoscow 142190Russia Moscow Institute of Physics and Technology Institutskiy per.9Dolgoprudny 141700Russia

Efficient nonlinear conversion requires that interacting optical waves maintain a consistent phase relationship when traveling in a medium despite its *** phase-matching,which is often used to compensate for the dispersion,is not applicable to optically isotropic nonlinear ***,we present a one-dimensional photonic crystal structure that allows the propagation of optical surface waves,both at the fundamental and third-harmonic frequencies,as an efficient medium for phasematched third-harmonic generation.A unique advantage of this structure is that the effective refractive indices for the surface waves are similar to the refractive index of air at both *** allows phase-matching between the first and third harmonics,and a visible collinear beam of the third harmonic is produced at the prism-coupled ***,these optical surface waves propagate over long distances even if a lossy nonlinear nanofilm is deposited onto the photonic crystal *** provide experimental results for third-harmonic generation at a wavelength of 410 nm for a bare dielectric Ta2O5/SiO2 multilayer structure and for the same structure coated with a 15-nm GaAs film.

关键词： nonlinear optics optical surface waves photonic crystals

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Multiwavelength Pyroreflectometry as a Method for Measuring True Temperature

Multiwavelength Pyroreflectometry as a Method for Measuring ...

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第二届仪器科学与技术国际学术研讨会

作者： Temur P. Salikhov valery v. Kan Scientific Association of "Physics-Sun" /Tashkent Uzbekistan Scientific Association of "Physics-Sun" /Tashkent Uzbekistan

＜正＞ Pyroreflectometry is a method in which the functions of pyrometer and reflectometer is combined in one device. This method enables one to measure simultaneously the radiance temperature and spectral reflectivity and emissivity of the heated body and to obtain its true （thermodynamic） temperature. In the present paper a new approach in pyroreflectometry based on the multiwavelength pulsed diffuse optical probing of the heated body by an additional light source and on simultaneous measuring the radiance temperatures and thermal radiation properties at different wavelengths by a multichannel pyrometer has been *** various techniques of multiwavelength pyroreflectometry are presented in the paper. The first setup is intended to make reflectivity and temperature measurements for refractory opaque materials at super high temperatures. The second experimental technique has been developed to perform reflectivity and temperature measurements for semitransparent materials near their melting points. The potential of the multiwavelength pyroreflectometry has been demonstrated in measuring thermal radiation properties, true melting temperatures and true phase transitions temperatures of oxide ceramic materials. The results obtained confirm that multiwavelength pyroreflectometry can be applied in measuring true temperatures and spectral optical properties of the advanced materials at high temperatures with high precision.

关键词： ceramics emissivity melting point pyrometry reflectivity semitransparent materials.

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点击化学--释义与目标

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化学进展 2008年第1期20卷 1-4页

作者： M. G. Finn Hartmuth C. Kolb valery v. Fokin K. Barry Sharpless 张欣豪吴云东不详香港科技大学化学系香港九龙

点击化学i自2001年由Sharpless提出以来,引起广泛的重视,并得以蓬勃的发展。许多综述对此领域的进展进行了归纳ii,赵卫光,李正名等在《有机化学》中发表中文综述介绍了点击化学的一些基本概念和应用iii。作为点击化学的提出者,Sharples... 详细信息

点击化学i自2001年由Sharpless提出以来,引起广泛的重视,并得以蓬勃的发展。许多综述对此领域的进展进行了归纳ii,赵卫光,李正名等在《有机化学》中发表中文综述介绍了点击化学的一些基本概念和应用iii。作为点击化学的提出者,Sharpless最近写了一篇文章深入浅出地阐释了点击化学的思想与愿景。该文由北山隆翻译成日文,并于日本化学会的《化学と工業》发表iv。Sharpless希望此文也能以中文的形式与中国读者见面。受Sharpless之托,我们将此文翻译成中文,以冀与更多同行分享。

关键词：《有机化学》释义中文化学会综述翻译

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Lattice oxygen activation in transition metal doped ceria

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Chinese Journal of Catalysis 2020年第6期41卷 977-984页

作者： Ya-Qiong Su Long Zhang valery Muravev Emiel J.M.Hensen Laboratory of Inorganic Materials&Catalysis Schuit Institute of CatalysisEindhoven University of TechnologyP.O.Box 5135600 MB EindhovenThe Netherlands

Density functional theory calculations were carried out to investigate the influence of doping transition metal(TM) ions into the ceria surface on the activation of surface lattice oxygen atoms. For this purpose, the structure and stability of the most stable(111) surface termination of CeO2 modified by TM ions was determined. Except for Zr and Pt dopants that preserve octahedral oxygen coordination, the TM dopants prefer a square-planar coordination when substituting the surface Ce ions. The surface construction from octahedral to square-planar is facile for all TM dopants, except for Pt(1.14 e v) and Zr(square-planar coordination unstable). Typically, the ionic radius of tetravalent TM cations is much smaller than that of Ce4+, resulting a significant tensile-strained lattice and explaining the lowered oxygen vacancy formation energy. Except for Zr, the square-planar structure is the preferred one when one oxygen vacancy is created. Thermodynamic analysis shows that TM-doped CeO2 surfaces contain oxygen defects under typical conditions of environmental catalysis. A case of practical importance is the facile lattice oxygen activation in Zr-doped CeO2(111), which benefits CO oxidation. The findings emphasize the origin of lattice oxygen activation and the preferred location of TM dopants in TM-ceria solid solution catalysts.

关键词： Lattice oxygen activation TM-doped CeO2(111) Density functional theory calculations Oxygen vacancy Square-planar coordination Coordination transformation CO oxidation

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