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Impact of natural disturbance, forest management and vegetation cover on topsoil biochemical characteristics of Tatra Mts.(slovakia)

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Journal of Mountain science 2020年第6期17卷 1294-1309页

作者： Jana GáFrikOVá Milan ZVARík Peter HANAJík Marek súLOVskY Ivana VYkOukOVá Faculty of Natural sciences Comenius UniversityBratislava84104Slovak Republic Faculty of Mathematics Physics and InformaticsComenius UniversityBratislava84104Slovak Republic Water Research Institute Bratislava81249Slovak Republic

Perturbations caused by windstorms usually lead to the harvesting and clearcutting of fallen trees and wood debris,especially in the areas of managed forest *** shifts in soils due to management practices play a crucial role in the restoration and maintaining of key ecosystem *** paper focuses on topsoil chemical properties in relation to vegetation type(trees,shrubs and herbs)evolving at windstorm damaged(in 2004)areas with former Norway spruce(Picea abies)forests in the Tatra ***(slovakia).We assessed the content of topsoil organic matter fractions(extractives,holocellulose(HC)and lignin(Lig)),carbon in microbial biomass(Cmic),soil organic matter(sOM)and the content of elements N,C,H and *** study plots represent different types of post-windthrow disturbance history/regime:wooden debris extraction(EXT),wooden debris not extracted(NEX),wooden debris extraction followed by wildfire(FIR),affected by the windstorm in 2014 with the subsequent wooden debris extraction(REX)and unaffected(REF).Our results revealed significant differences among sites in the content of dichloromethane extractives(EXT *** and FIR),acetone extractives(NEX ***,FIR and REF),ethanol extractives(FIR ***,NEX and REF),water extractives(FIR ***,NEX)and Cmic(EXT ***,FIR and REF).The topsoil of Vaccinium myrtillus and Picea abies showed a higher ratio of C/N,N/Lig,and Lig/HC compared to Rubus idaeus,Avenella flexuosa,Calamagrostis villosa,and Larix *** content of N,C,H and s varied between topsoil with shrubs(Vaccinium myrtillus,Rubus idaeus)and grasses(Avenella flexuosa,Calamagrostis villosa).A positive correlation between soil organic matter(sOM)and polar extractives(r=0.81)and a negative correlation between sOM and HC(r=-0.83)was *** carbon content in microbial biomass(Cmic)is positively correlated with acid soluble lignin(AsL)(r=0.85).We also identified a strong correlation between klason lignin(kL)and the Lig/HC ratio(r=0.97).

关键词： Windthrow Wildfire Organic matter fractions Vegetation type Norway spruce Topsoil chemical properties

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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： M.Grandin H.k.Connor s.Hoilijoki M.Battarbee Y.Pfau-kempf u.Ganse k.Papadakis M.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NAsA Goddard space Flight Center GreenbeltMD20771USA space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** solar wind Magnetosphere Ionosphere Link Explorer(sMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their soft X-ray Imager(sXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by sMILE sXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the sMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation sMILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

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Periodic Algebras Generated by Groups

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Algebra Colloquium 2015年第4期22卷 541-554页

作者： s. Albeverio B.A. Omirov u.A. Rozikov Institut fur Angewandte Mathematik and HCM universitat Bonn Bonn Germany Institute of Mathematics 29 Do'rmon Yo'li str. 100125 Tashkent Uzbekistan

We consider algebras with basis numerated by elements of a group G. We fix a function f from G × G to a ground field and give a multiplication of the algebra which depends on f. We study the basic properties of such algebras. In particular, we find a condition on f under which the corresponding algebra is a Leibniz algebra. Moreover, for a given subgroup G of G we define a G-periodic algebra, which corresponds to a G-periodic function f, we establish a criterion for the right nilpotency of a G-periodic algebra. In addition, for （7 = Z we describe all 2Z- and 3Z-periodic algebras. some properties of nZ-periodic algebras are obtained.

关键词： periodic algebra Leibniz algebra group

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Biomass energy cost and feasibility of gasifier based biomass power generation system

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International Journal of Agricultural and Biological Engineering 2013年第4期6卷 55-63页

作者： khambalkar V P kankal u s karale D s Gangde C N Department of Farm Power and Machinery College of Agricultural Engineering and Technology and Dr.Panjabrao Deshmukh Agricultural UniversityAkola MS 444104India

The present research work has been carried out on biomass based on 10 kW capacity gasifier power generation system installed at College of Agricultural Engineering and Technology,*** Deshmukh Agricultural university(***),Akola Maharashtra,*** main objectives were to evaluate various costs and benefits involved in the power generation *** costs of energy per unit were calculated for the first year of *** economics of gasifier based power generation system and thereby the feasibility of the system was examined by estimating per unit cost,Net Present Value(NPV),Benefit Cost Ratio(BCR),Internal Rate of Return(IRR)and payback *** discount cash flow method was used to find out the *** the present analysis,three costs viz.,installed capital cost,operation and maintenance cost,and levelised replacement cost were examined for the evaluation of the power generation per *** rate on investment in case of subsidy(Case I)and in case without subsidy(Case II)for installation cost of system was considered as 12.75%.The BCR comes in Case I for operating duration of 22 h,20 h,and 16 h are 1.24,1.18,and 1.13,*** for Case II BCR comes 1.44,1.38,and *** IRR comes in Case I for operating duration of 22 h,20 h,and 16 h are 26%,22%,and 19%,*** for Case II,IRR comes 52%,44%,and 39%for operating duration of 22 h,20 h,and 16 h,*** payback period in the present analysis was worked *** payback period for biomass based gasifier power generation system was observed to be for Case I from three to four years and for Case II it was one to two years.

关键词： cost of biomass energy biomass power generation system discounted cash flow benefit cost ratio net present value payback period internal rate of return

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Enhanced microbial reduction of aqueous hexavalent chromium by shewanella oneidensis MR-1 with biochar as electron shuttle

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Journal of Environmental sciences 2022年第3期34卷 12-25页

作者： Cholnam ri Jingchun Tang Feng Liu Honghong Lyu Fengxiang Li College of Environmental science and Engineering Nankai UniversityTianjin 300350China key Laboratory of Pollution Processes and Environmental Criteria Ministry of EducationChina Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation Tianjin 300350China Tianjin key Laboratory of Clean Energy and pollution control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin 300401China state Academy of sciences Institute of MicrobiologyPyongyangDemocratic People's Republic of Korea Tianjin Eco-Environmental Comprehensive support Center Tianjin300191China

Biochar, carbonaceous material produced from biomass pyrolysis, has been demonstrated to have electron transfer property(associated with redox active groups and multi condensed aromatic moiety), and to be also involved in biogeochemical redox reactions. In this study, the enhanced removal of Cr(VI) by shewanella oneidensis MR-1(MR-1) in the presence of biochars with different pyrolysis temperatures(300 to 800 ℃) was investigated to understand how biochar interacts with Cr(VI) reducing bacteria under anaerobic condition. The promotion effects of biochar(as high as 1.07~1.47 fold) were discovered in this process, of which the synergistic effect of BMBC700(ball milled biochar) and BMBC800 with MR-1 was noticeable, in contrast, the synergistic effect of BMBCs(300–600 ℃) with MR-1 was not recognized. The more enhanced removal effect was observed with the increase of BMBC dosage for BMBC700 + MR-1 group. The conductivity and conjugated O-containing functional groups of BMBC700 particles themselves has been proposed to become a dominant factor for the synergistic action with this strain. And, the smallest negative Zeta potential of BMBC700 and BMBC800 is thought to favor decreasing the distance from microbe than other BMBCs. The results are expected to provide some technical considerations and scientific insight for the optimization of bioreduction by useful microbes combining with biochar composites to be newly developed.

关键词： sheiuanella oneidensis MR-1 Cr(VI)reduction Biochar Pyrolysis temperature ssynergistic effect

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Efficiency assessment of coal mine safety input by data envelopment analysis

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Journal of China university of Mining and Technology 2008年第1期18卷 88-92页

作者： TONG Lei DING ri-jia school of Management China University of Mining ＆Technology Beijing 100083 China

In recent years improper allocation of safety input has prevailed in coal mines in China, which resulted in the frequent accidents in coal mining operation. A comprehensive assessment of the input efficiency of coal mine safety should lead to improved efficiency in the use of funds and management resources. This helps government and enterprise managers better understand how safety inputs are used and to optimize allocation of resources. study on coal mine＇s efficiency assessment of safety input was con- ducted in this paper. A C^2R model with non-Archimedean infinitesimal vector based on output is established after consideration of the input characteristics and the model properties. An assessment of an operating mine was done using a specific set of input and output criteria. It is found that the safety input was efficient in 2002 and 2005 and was weakly efficient in 2003. However, the efficiency was relatively low in both 2001 and 2004. The safety input resources can be optimized and adjusted by means of projection theory. such analysis shows that, on average in 2001 and 2004, 45% of the expended funds could have been saved. Likewise, 10% of the safety management and technical staff could have been eliminated and working hours devoted to safety could have been reduced by 12%. These conditions could have riven the same results.

关键词： safety input coal mining enterprise efficiency assessment data envelopment analysis (DEA)

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Chemical, isotopic and amino acid composition of Mukundpura CM2.0(CM1) chondrite: Evidence of parent body aqueous alteration

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Geoscience Frontiers 2019年第2期10卷 495-504页

作者： N.G.Rudraswami A.k.Naik R.P.Tripathi N.BhANDari s.G.karapurkar M.shyam Prasad E.V.s.s.k.Babu u.V.R.Vijaya sarathi National Institute of Oceanography (Council of scientific and Industrial Research) 78 BGKT Extension science and spirituality Research Institute National Geophysical Research Institute (Council of scientific and Industrial Research) Indian Institute of Chemical Technology (Council of scientific and Industrial Research)

The carbonaceous chondrites are intriguing and unique in the sense that they are the only rocks that provide pristine records of the early solar nebular processes. We report here results of a detailed mineralogical, chemical, amino acid and isotopic studies of a recently observed fall at Mukundpura, near Jaipur in Rajasthan, India. Abundance of olivines in this meteorite is low and of serpentine minerals is high. FeO/siO_2 = 1.05 in its Poorly Characterized Phases(PCP) is similar to that observed in other CM2.0 chondrites. The water content of ～9.8 wt.% is similar to that found in many other CM *** examination of matrix shows that its terrestrial weathering grade is WO but aqueous parent body alteration is high, as reflected in low abundance of identifiable chondrules and abundant remnants of chondrules(～7%). Thus, most of the chondrules formed initially have been significantly altered or dissolved by aqueous alterations on their parent bodies. The measured bulk carbon(2.3%) and nitrogen content and their isotopic(δ^(13)C =-5.5‰, δ^(15)N = 23.6%0) composition is consistent with CM2.0 classification probably bordering CM1. several amino acids such as Alanine, serine, Proline, Valine, Threonine,Leucine, Isoleucine, Asparagine and Histamine are present. Tyrosine and Tryptophan may occur in trace amounts which could not be precisely determined. All these data show that Mukundpura chondrite lies at the boundary of CM2.0 and CM1 type carbonaceous chondrites making it one of the most primitive chondrites.

关键词： Carbonaceous chondrite Mukundpura CM Isotope Amino acid

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Effectiveness of heat and mass transfer on mixed convective peristaltic motion of nanofluid with irreversibility rate

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Communications in Theoretical Physics 2021年第10期73卷 36-46页

作者： Y Akbar F M Abbasi u M Zahid s A shehzad Department of Mathematics COMSATS University IslamabadIslamabadPakistan Department of Mathematics COMSATS University IslamabadSahiwalPakistan

Entropy generation is one of the key features in analysis as it exhibits irreversibility of the system. Therefore, the present study investigates the entropy generation rate in a mixed convective peristaltic motion of a reactive nanofluid through an asymmetrical divergent channel with heat and mass transfer characteristics. The endorsed nanofluid model holds thermophoresis and Brownian diffusions. Mathematical modeling is configured under the effects of mixed convection, heat generation/absorption and viscous dissipation. A chemical reaction is also introduced for the description of mass transportation. The resulting system of differential equations is numerically tackled by employing the shooting method. The findings reveal that entropy generation rises by improving the Brownian motion and thermophoresis parameters. The temperature of the nanofluid decreases due to rising buoyancy forces caused by the concentration gradient. The concentration profile increases by increasing the chemical reaction parameter. The velocity increases by enhancing the Brownian motion parameter.

关键词： peristaltic flow thermophoresis and Brownian motion mixed convection chemical reaction irreversibility nanofluid

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salinity Distribution at Canal Istanbul and Its Possible Impacts on the Northern Marmara sea

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China Ocean Engineering 2020年第6期34卷 881-888页

作者： Şehriban sAÇu Tarkan ERDIk OlgayŞEN Istanbul Technical university MaslakIstanbul 34467Turkey

Turkey has announced its plan to construct a new waterway, Canal Istanbul, parallel to the Bosphorus. In this study,the influence of Canal Istanbul on salinity distribution in the northern Marmara sea is investigated using a previously calibrated 3 D hydrodynamic and salinity model. Moreover, the salinity field of the canal and its propagation are examined based on various meteorological cases. Finally, the flow structure of the canal is determined. It is calculated that at the southern end of the canal, mainly unidirectional flow(from the Black sea to the Marmara sea)occurs during 68% of the simulation period. A two-layer flow is seen only 28% of the time with a weak lower layer flow, whereas this value decreases to 4% at the north end of the canal. In the southward direction(to the Marmara sea), velocities higher than 1.5 m/s are rarely observed along the canal. The average surface salinity difference in the northern Marmara sea due to the construction of the canal is calculated to be smaller than 0.50 ppt. The salinity difference gradually diminishes as water depth increases and after 25 m(from the surface) almost no difference is observed.

关键词： Canal Istanbul Marmara sea salinity distribution hydrodynamic modeling

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Exponential stability for impulsive Cohen-Grossberg neural networks with time-varying delays and distributed delays

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International Journal of Intelligent Computing and Cybernetics 2013年第2期6卷 144-157页

作者： Cheng-De Zheng ri-Ming sun school of science Dalian Jiaotong UniversityDalianPeople’s Republic of Chinaand Zhanshan Wang School of Information Science and EngineeringNortheastern UniversityShenyangPeople’s Republic of China

Purpose–The purpose of this paper is to develop a methodology for the existence and global exponential stability of the unique equilibrium point of a class of impulsive Cohen-Grossberg neural ***/methodology/approach–The authors perform M-matrix theory and homeomorphism mapping principle to investigate a class of impulsive Cohen-Grossberg networks with time-varying delays and distributed *** approach builds on new sufficient criterion without strict conditions imposed on self-regulation ***–The authors’approach results in new sufficient criteria easy to verify but without the usual assumption that the activation functions are bounded and the time-varying delays are *** example shows the effectiveness and superiority of the obtained results over some previously known ***/value–The novelty of the proposed approach lies in removing the usual assumption that the activation functions are bounded and the time-varying delays are differentiable,and the use of M-matrix theory and homeomorphism mapping principle for the existence and global exponential stability of the unique equilibrium point of a class of impulsive Cohen-Grossberg neural networks.

关键词： Neural nets stability(control theory) Equilibrium methods Cohen-Grossberg networks Impulse Distributed delays Exponential stability

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