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Fragmentation Cross Sections of 158 AgeV Pb Projectiles

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Chinese Physics Letters 2007年第10期24卷 2800-2803页

作者： g. Sher m.I. Shahzad m. Hussain Physics Division PINSTECH Islamabad Pakistan Department of Physics University of the Punjab Lahore Pakistan

We investigate the fragmentation cross sections of 158 AgeV ^207Pb projectile interacting with different targets using CR39 nuclear track detectors. The exposure is made at SPS beam facility of CERN. The detectors are chemically etched to obtain data in the form of etched cone length. The nuclear and electromagnetic contributions to the measured total charge-changing cross sections are investigated. The estimated results are compared with those found in the literature for similar research work.

关键词： coated conductor buffer layer self-epitaxy CeO2

Thermodynamics of Phantom Energy Accreting onto a Black Hole in Einstein–Power–maxwell gravity

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Chinese Physics Letters 2013年第10期30卷 34-37页

作者： g.Abbas R.m.Ramzan Department of mathematics COMSATS Institute of Information TechnologySahiwal-67000Pakistan Department of mathematics The Islamia University BahawalpurPakistan

We investigate the phantom energy accretion onto a 3D black hole formulated in the Einstein–Power–maxwell theory,and present the conditions for critical accretion of phantom energy onto the black ***,we discuss the thermodynamics of phantom energy accreting onto the black hole and find that the first law of thermodynamics is easily satisfied while the second law and the generalized second law of thermodynamics remain invalid and conditionally valid,*** results for the Banados–Teitelboim–Zanelli black hole can be recovered by taking maxwellian contribution equal to zero.

关键词： maxwell black law Power

Simultaneous photoinduced generation of Fe^(2+) and H_2O_2 in rivers:An indicator for photo-Fenton reaction

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Journal of Environmental Sciences 2016年第9期28卷 34-38页

作者： Khan m.g.mostofa Hiroshi Sakugawa Institute of Surface-Earth System Science Tianjin University graduate School of Biosphere Science Department of Environmental Dynamics and ManagementHiroshima University

The photo-Fenton reaction is a key source of the highly reactive hydroxyl radical（HOU） that is produced by the reaction of simultaneous photo-induced generation of Fe^（2＋）-dissolved organic matter（DOm） with H_2O_2 in sunlit surface waters as well as in the treatment of organic pollutants in the advanced oxidation processes（AOPs）.Concentrations of both H_2O_2 and Fe^（2＋）-DOm were dependent on time and total solar intensity flux,and their levels were highest in the diurnal samples collected at noon compared with the samples collected during the period before sunrise and after sunset.H_2O_2 and Fe^（2＋）-DOm concentrations during monthly readings were also found higher in comparison with the diurnal samples,shortly before sunrise or after sunset.A π-electron bonding system is formed between Fe and the functional groups in DOm（Fe-DOm）,through electron donation from the functional groups of DOm to an empty d-orbital of *** π-electron is loosely bound and is highly susceptible to a rapid excitation upon light exposure that will provide better understanding of the formation of aqueous electrons,superoxide radical anions,H_2O_2 and finally,photo-Fenton reactions,*** results imply that simultaneous generation of H_2O_2 and Fe^（2＋）-DOm upon sunlight exposure during the daytime is most likely to be the key photo-Fenton reaction pathway,taking place in surface waters.

关键词： Photo-Fenton reaction Fe^(3+) Fe^(2+) Dissolved organic matter H_2O_2 Light

The effect of ozone and drought on the photosynthetic performance of canola

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Journal of Integrative Agriculture 2018年第5期17卷 1137-1144页

作者： Bheki g maliba Prabhu m Inbaraj Jacques m Berner Unit for Environmental Sciences and management North-West University Eskom Research Testing and Development Department of Chemistry School of ScienceRK University

Canola plants were fumigated in open-top chambers with ozone（O3）（120 ppb）under well-watered（WW）and water-stressed（WS）conditions for 4 ***-fumigated plants were also studied to facilitate comparison between treatments for the same week and over ***,the treatments were：WW,WW-O3,WS and *** fast chlorophyll a fluorescence transients OJIP for the four treatments emitted upon illumination of dark-adapted leaves were measured after week 1,2,3,4 and analysed by the JIP-test to evaluate the resulting changes in photosynthetic *** fumigation led to a decline of total performance index（PI（total））in well-watered *** effect of O3 was minor under drought conditions,as revealed by a decrease of PI（total） by 3%.The PI（total） decreased as the treatment was prolonged,due to leaf ageing for all cases and the decline was more pronounced under *** the average of all weeks,WW had the highest PI（total)and the lowest WW-O3（decrease by 27%）,while in WS and WS-O3,it was lower than WW（14 and 17%,respectively）.We found that the absorption（ABS）/reaction centre（RC）increases,while the maximum quantum yield of primary photochemistry（φ（Po））undergoes slight changes,and trapping（TR0）/RC closely followed the increase in ABS/*** indicates that O3and drought caused an increase in the functional antenna *** maximum quantum yield of primary photochemistry showed slight differences for all treatments and over time,suggesting that this parameter is less sensitive to drought and O3 ***,the more sensitive components of the photosynthetic electron transport chain appeared to be the probability that an electron from the intersystem electron carriers is transferred to reduce end electron acceptors at the PSI acceptor side（δ（Ro））and the RC density on a chlorophyll basis（RC/ABS）.

关键词： canola Chl a fluorescence JIP-test open-top chamber ozone

Cosmology with Two Compactification Scales

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Chinese Physics Letters 2000年第4期17卷 310-312页

作者： A.g.Agnese m.La Camera Dipartimento di Fisica delPUniversita di genova Istituto Nazionale di Fisica NucleareSezione di Genova Via Dodecaneso 3316146 GenovaItaly

We consider a(4+d)-dimensional spacetime broken up into a(4-n)-dimensional minkowski spacetime(where n goes from 1 to 3)and a compact(n+d)-dimensional *** the present time the n compactification radii are of the order... 详细信息

关键词： manifold. length. minkowski

High Temperature Deformation Behavior of 4340 Steel: Activation Energy Calculation and modeling of Flow Response

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Journal of Iron and Steel Research International 2013年第12期20卷 133-139页

作者： S V Sajadifar g g Yapici m Ketabchi B Bemanizadeh mechanical Engineering Department Ozyegin University mining and metallurgical Engineering Department Amirkabir University of Technology Islamic Azad University Karaj Branch

The 4340 steel is extensively utilized in several industries including automotive and aerospace for manufac- turing a large number of structural components. Due to the importance of thermo-mechanical processing in the pro- duction of steels, the dynamic recrystallization （DRX） characteristics of 4340 steel were investigated. Namely, hot compression tests on 4340 steel have been performed in a temperature range of 900-- 1200 ℃ and a strain rate range of 0.01--1 s-1 and the strain of up to 0.9. The resulting flow stress curves show the occurrence of dynamic recrys- tallization. The flow stress values decrease with the increase of deformation temperature and the decrease of strain rate. The microstrueture of 4340 steel after deformation has been studied and it is suggested that the evolution of DRX grain structures can be accompanied by considerable migration of grain boundaries. The constitutive equations were developed to model the hot deformation behavior. Finally based on the classical stress-dislocation relations and the kinematics of the dynamic recrystallization; the flow stress constitutive equations for the dynamic recovery period and dynamic reerystallization period were derived for 4340 steel, respectively. The validity of the model was demon- strated by demonstrating the experimental data with the numerical results with reasonable agreement.

关键词： 4340 steel hot deformation activation energy dynamic recrystallization, modeling strain rate sen- sitivity

ON THE IDENTIFICATION OF RESIDUAL ImPACT PROPERTIES OF mATERIALS BY ACOUSTO-ULTRASONICS——A PATTERN RECOgNITION APPROACH

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Acta mechanica Sinica 1995年第1期11卷 34-43页

作者： g.J.molina Y.m.Haddad Dept.of mechanical Engineering University of OttawaOttawaCanada K1N 6N5

This paper deals with the application of Acousto-ultrasonics,in con- junction with Pattern Recognition and Classification techniques,to the identification of residual impact properties of a class of polymeric material,namely,Polyvinylchlo- ride(PVC).PVC specimens of different low-energy repeated impact damage states are processed by Acousto-ultrasonics(AU)to retrieve AU signals in the form of dig- italized *** AU signals are grouped as distinct classes,each pertaining to a known level of repeated impact *** features of these AU signals are used to build Pattern Recognition(PR)*** classifiers are used to identify unknown damage states in other PVC specimens by classifying the re- trieved AU signals as belonging to one of the *** obtained results indicate that Acousto-ultrasonics in combination with Pattern Recognition and Classification techniques can be used for the quantitative non-destructive identification of damage states in PVC specimens of unknown low-energy repeated impact conditions.

关键词： pattern recognition acousto-ultrasonics impact damage quantitative non-destructive examination

Review:Resuspension of wall deposits in spray dryers

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1762-1774页

作者： HANUS m.J. LANgRISH T.A.g. School of Chemical and Biomolecular Engineering University of Sydney Sydney NSW 2006 Australia

Wall deposition occurs in spray dryers when dried or partially dried particles contact and adhere to the walls during operation, thus reducing the yield of product collected. Wall deposits also present a product contamination risk and a fire or explosion risk when spray drying products that oxidize exothermically, such as milk powder. Re-entrainment is the resuspension of spray dryer wall deposits into the main gas stream for collection as product. Literature suggests that the process for re-entrainment of particles from spray dryer wall deposits is strongly dependent on particle size and gas velocity.

关键词： Wall deposition Spray dryers Dried particles Re-entrainment Adhesive forces

Dipole (hyper)polarizabilities of neutral silver clusters

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Chinese Physics B 2016年第12期25卷 217-222页

作者： Francisco E Jorge Luiz g m de macedo Departarnento de Fisica Universidade Fedoral do Espirito Santo 29060-900 Vitoria Brazil Unidade Academica de Fisica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Faculdade de Biotecnologia ICB Universidade Federal do Para 66075-110 Belem Brazil

At the Douglas-Kroll-Hess （DKI4） level, the B3PW91 functional along with the all-eleclron relativistic basis sets of valence triple and quadruple zeta qualities are used to determine the structure, stability, and electronic properties of the small silver clusters （Agn, n ≤ 7）. The results presented in this study are in good agreement with the experimental data and theoretical values obtained at a higher level of theory from the literature. Static polarizability and hyperpolarizability are also reported. It is verified that the mean dipole polarizability per atom exhibits an odd-even oscillation and that the polarizability anisotropy is directly related to the cluster shape. In this article, the first study of hyperpolarizabilities of small silver clusters is presented. Except for the monomer, the second hyperpolarizabilities of the silver clusters are significantly larger than those of the copper clusters.

关键词： B3PW91 functional all-electron basis sets non-relativistic and DKH2 calculations silver clusters,dipole (hyper)polarizabilities