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Importance of heavy quark longitudinal structure function measurements at future circular collider energies

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Chinese Physics C 2021年第6期45卷 56-65页

作者： g.r.Boroun Physics Department Razi UniversityKermanshah 67149Ira

In this article,we consider the ratio of structure functions for heavy quark pair production at low values *** importance of this ratio for charm and beauty pair production is examined according to the Hadron Electron ring Accelerator(HErA)*** behavior of these ratios is considered due to the hard pomeron behavior of the gluon distribution *** results are in good agreement with the HErA *** this data to the range of new energies underscores the importance of these measurements for heavy *** ratio of charm and beauty structure functions at the proposed Large Hadron electron Collider(LHeC)is considered as a function of invariant center-of-mass *** top pair production this ratio is extracted with known kinematics of the LHeC and Future Circular Collider electron-hadron(FCC-eh)*** of the results obtained for the ratio of top structure functions in LHeC and FCC-eh are proportional to the specified inelasticity range.

关键词： future circular colliders heavy quarks longitudinal structure function

real-time prediction of projectile penetration to laminates by training machine learning models with finite element solver as the trainer

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Defence Technology（防务技术） 2021年第1期17卷 147-160页

作者： Pushkar Wadagbalkar g.r.Liu Department of Aerospace Engineering and Engineering Mechanics University of CincinnatiCincinnatiOH 45219USA

Studies on ballistic penetration to laminates is complicated,but important for design effective protection of *** means of study is expensive and can often be *** simulation has been an excellent supplement,but the computation is *** aim of this thesis was to develop and test an effective tool for real-time prediction of projectile penetrations to laminates by training a neural network and a decision tree regression model.A large number of finite element models were developed;the residual velocities of projectiles from finite element simulations were used as the target data and processed to produce sufficient number of training *** focused on steel 4340tpolyurea laminates with various *** different 3D shapes of the projectiles were modeled and used in the *** trained neural network and decision tree model was tested using independently generated test samples using finite element *** predicted projectile velocity values using the trained machine learning models are then compared with the finite element simulation to verify the effectiveness of the ***,both models were trained using a published experimental data of projectile impacts to predict residual velocity of projectiles for the unseen *** of both the models was evaluated and *** trained with Finite element simulation data samples were found capable to give more accurate predication,compared to the models trained with experimental data,because finite element modeling can generate much larger training set,and thus finite element solvers can serve as an excellent *** study also showed that neural network model performs better with small experimental dataset compared to decision tree regression model.

关键词： Finite element simulations Machine learning Neural networks Impact analysis Protective laminates Projectile Decision tree

Synthesis and characterization of hybrid graphene nanocoolant for heat transfer dissipation in microchannel heat sinks

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Chinese Journal of Chemical Engineering 2020年第3期28卷 913-922页

作者： Sudha g. Parthiban r. Department of Chemical Engineering Sri Venkateswara College of EngineeringPennalurTamilnadu 602117India Department of Chemical Engineering SSN College of EngineeringKalavakkamTamilnadu 603110India

An attempt is made to examine the effect of hybrid nanocoolant in microchannel heat sink for computer ***-hybrid coolants with graphene as one of the prime components are synthesized and images of the particles are shown using scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Heat transfer properties like thermal conductivity of the hybrid fluid,specific heat,density,and viscosity are evaluated experimentally and *** heat transfer characteristics are also studied in heat sink channels of micro level in the processors of personal *** parameters like internal heat transfer coefficient,thermal resistances and base temperature representing the processor temperature are examined for the applied heater power of 325 *** coolant dilution was varied in the range of 0.05 vol%,0.075 vol%and 0.1 vol%and the base temperature is *** recorded lowest base temperature is 310.01 K for the concentration of 0.1 vol%graphene-iron oxide(gFO)system for 0.5 mm fin spacing for the graphene-iron oxide hybrid coolant and for graphene oxide–iron oxide(gOFO)hybrid coolant it is 311.24 K for the same operating conditions.

关键词： graphene hybrid nanocoolant Microchannel CPU base temperature

robust nonlinear control for nuclear reactors using sliding mode observer to estimate the xenon concentration

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Nuclear Science and Techniques 2016年第2期27卷 106-114页

作者： g.r.Ansarifar H.r.Akhavan Department of Nuclear Engineering Faculty of Advanced Sciences and Technologies University of Isfahan

This paper presents findings on the sliding mode controller for a nuclear reactor. One of the important operations in nuclear power plants is load following. In this paper, a sliding mode control system, which is a robust nonlinear controller, is designed to control the pressurizedwater reactor power. The reactor core is simulated based on the point kinetics equations and six delayed neutron groups. Considering neutron absorber poisons and regarding the limitations of the xenon concentration measurement, a sliding mode observer is designed to estimate its value, and finally, a sliding mode control based on the sliding mode observer is presented to control the core power of reactor. The stability analysis is given by means Lyapunov approach; thus, the control system is guaranteed to be stable within a large range. The employed method is easy to implement in practical applications, and moreover,the sliding mode control exhibits the desired dynamic properties during the entire output-tracking process independent of perturbations. Simulation results are presented to demonstrate the effectiveness of the proposed observerbased controller in terms of performance, robustness and stability.

关键词：鲁棒非线性控制滑模观测器核反应堆估计氙气气浓度非线性鲁棒控制器滑模控制系统

First record of contourites from Lower Devonian Lip-trap Formation in southeast Australia

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Science China Earth Sciences 2008年第7期51卷 939-946页

作者： g.r.SHI Key Laboratory of Biogeology and Environmental geology of China Education Ministry Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Typical contourite deposits associated with submarine turbidite fan deposits are recognized for the first time from the Lower Devonian Liptrap Formation at Cape Liatrap, Victoria in southeast Australia. The contourites are well integrated within the turbidite fan deposits and are characterized by thin (5-8 cm), lenticular, well-sorted coarse-grained siltstones to fine-grained sandstones with current-ripples and cross beddings. The palaeocurrent directions of the turbidite fan and contourites are perpendicular to each other, with the former directed generally westward while the latter varying from 165° to 190° southward. In view of the facies types and architecture, we suggest that the turbidite fan was developed at the base of a westward inclined palaeo-slope, at the front of which the contourites were deposited as a result of southward flowing deep-sea contour (geostrophic) currents. The depositional setting inter- preted for the Liptrap Formation thus may provide a provisional model for the Lower Devonian conti- nental slope and abyssal basin environment in the southeastern part of the Melbourne Trough.

关键词： Contourite turbidite Cape Liptrap Liptrap Formation southeast Australia

Calculation of gluon Distribution Functions in Leading Order by regge-like Behavior at Low-x

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Communications in Theoretical Physics 2005年第5X期44卷 891-896页

作者： g.r. Boroun Physics Department Razi University Kermanshah 67149 Iran

An approximate analytical form of the gluon distribution function from the derivative F2 proton structure function data at low-x assuming the regge-like behavior of the gluon distribution function at this limit is presented. In this method, we calculate λ and C parameters for each low-x value at several Q^2 values using the scaling violation of the F2 proton structure function. For low-x, A is found to be independent of x within the experimental accuracy. We make use of the leading order Altarelli-Parisi （A-P） evolution equations in our analysis. To test the validity of our new determined gluon distribution functions, we compare them with the QCD parton distribution functions at low-x region.

关键词： regge-like behavior DgLAP equation for gluon low x

Approach for C_(1)to C_(2)products commencing from carbon dioxide:A brief review

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Petroleum 2024年第3期10卷 373-398页

作者： g.r.Dey radiation and Photochemistry Division Bhabha Atomic Research CentreTrombayMumbai 400085India Homi Bhabha National Institute AnushaktinagarMumbai 400094India

The carbon dioxide(CO_(2))conversion to useable compounds remains a great contest to scientists,engineers,and environmentalists with regard to the reverse of the oxidative degradation of *** conversion is essential for the development of complementary fuels and raw materials for various industries,which in turn will help in avoiding the drastic increase in tropospheric temperature due to greenhouse effect leading to global *** solar energy is the earth's essential power source along with the other various forms of energy for example fossil fuels,hydropower,wind,and biomaterials,*** final goal is to establish the artificial photosynthesis,which can be replicated thru various chemical reduction techniques of CO_(2)by employing appropriate photo-,thermal-and electro-catalysts in order to produce different one carbon atom(C_(1))and higher carbon atoms containing ***,the utilization of clean and sustainable CO_(2)towards high-value products is of great interest today due to the recognized environmental worries and subsequent lessening of the fossil fuels utilization load to meet the energy demand of *** way,solar energy can directly and/or indirectly be altered and stored in chemical energy form for industrial as well as societal *** this article our endeavor is to summarize the advances in CO_(2)chemical reduction research area till date especially in free radical-based methods such as electrochemical,photochemical and plasma chemical for the development of carbon species up to two carbon(C_(2))atoms containing products perceived in the chemical reduction of CO_(2).The author hopes that this piece of work will be helpful to researchers and readers who are focused on the field of CO_(2).

关键词： Photocatalysis Electrocatalysis Plasmolysis Thermolysis Carbon dioxide Chemical reduction

The interplay between leaf water potential and osmotic adjustment on photosynthetic and growth parameters of tropical dry forest trees

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Journal of Forestry research 2023年第1期34卷 177-186页

作者： Tiago de Sousa Leite romulo Magno Oliveira de Freitas Nildo da Silva Dias Jeferson Luiz Dallabona Dombroski Narjara Walessa nogueira Federal University of Mato grosso CuiabáMTBrazil Federal Institute of Education Science and Technology of Rio Grande do NortePau dos FerrosRNBrazil Federal rural University of the Semi-Arid region MossoróRNBrazil

Mimosa tenuiflora and Piptadenia stipulacea are commonly accepted as drought-tolerant species but little is known about their response to drought followed by ***,the interplay between leaf water potential and osmotic adjustment on photo synthetic and growth parameters of these species was examined.A greenhouse study was conducted in a split-plot design with two water conditions in the main plots(control;drought followed by rehydration),and eight sampling times in the subplots(1,4and 7 days of drought,and 1,3,6,12,and 17 days of rehydration).Plant water status and biochemical changes were assessed as well as leaf gas exchange and subsequent *** drought stress,both species maintained a low leaf water potential throughout the day by accumulating compatible solutes,thus allowing a rapid and full recovery of water status when *** these plants minimized water loss by closing their stomata,neither showed stomatal limitations to *** inhibition of this process during drought was possibly related to mesophyll limitations as well as to a reversible downregulation of photo systems,along with adjustments of their *** deficits also triggered morphological adaptations at the whole plant level,leading to reduced growth,mainly of the shoots in *** and the roots in ***.

关键词： Drought stress rehydration gas exchange Plant biomass

Mercury in sediments and vegetation in a moderately contaminated salt marsh (Tagus Estuary, Portugal)

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Journal of Environmental Sciences 2010年第8期22卷 1151-1157页

作者： Joao Canário Carlos Vale Laurier Poissant Marta nogueira Martin Pilote Vasco Branco INrB I.P./IPIMAr Av. Brasília Environment Canada Science and Technology Branch

Depth variations of total mercury （Hg） and methylmercury （MeHg） concentrations were studied in cores from non-colonized sediments, sediments colonized by Halimione portulacoides, Sarcocornia fruticosa and Spartina maritima and belowground biomass, in a moderately contaminated salt marsh （Tagus Estuary, Portugal）. Concentrations in belowground biomass exceeded up to 3 （Hg） and 15 （MeHg） times the levels in sediments, and up to 198 （Hg） and 308 （MeHg） times those found in aboveground parts. Methylmercury in colonized sediments reached 3% of the total Hg, 50 times above the maximum values found in non-colonized sediments. The absence of correlations between total Hg concentrations in sediments and the corresponding MeHg levels suggested that methylation was only dependent on the environmental and microbiological factors. The analysis of belowground biomass at high-depth resolution （2 cm） provided evidence that Hg and MeHg were actively absorbed from sediments, with higher enrichment factors at layers where higher microbial activity was probably occurring. The results obtained in this study indicated that the biotransformation of Hg to the toxic MeHg could increase the toxicity of plant-colonized sediments.

关键词： mercury methylmercury salt marshes Tagus Estuary Portugal