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Chinese Journal Of Geochemistry 2015年第3期34卷 447-458页

作者： J.madhavaraju A.n.sial s.m.Hussain r.nagarajan s.ramasamy Estación regional del noroeste Instituto de GeologíaUniversidad Nacional Autónoma de México nucleo de Estudos Geoquímicos e Laborató rio de Isótopos Estáveis (nEG - LABIsE) Departmento de GeologiaUniversidade Federal de Pernambuco Department of Geology University of Madras Department of Applied Geology School of Engineering and Science Curtin University

Petrography, carbon and oxygen isotopic study was carried out to interpret isotopic variations on the predominant carbonate sequence of the Dalmiapuram Formation of the Cauvery Basin, south India. The common petrographic types identified in the Dalmiapuram Formation range from wackestone to boundstone. The gray shale and limestone members show large variations in d13 C and d18 O values(Gray shale member: +1.44 to +2.40 %VPDB,-3.05 to-5.92 % VPDB, respectively; Limestone member:-6.07 to +2.93 % VPDB;-7.08 to-0.39 %VPDB; respectively). In the present study, the carbon and oxygen values are not correlated, which supports the fact that these limestones retain their primary isotopic signatures. In carbon isotope curve, one negative shift is identified in the gray shale member and a positive isotopic excursion is detected in the coral algal limestone(CAL).The observed positive isotopic excursion in the lower part of the CAL correlates with OAE1 d and suggests the global nature of the late Albian OAE1 d in the Cauvery Basin.

关键词：稳定同位素岩相学盆地印度蕴涵碳酸盐岩氧同位素偏移检测

Interplay of parallel electric field and trapped electrons in kappa-maxwellian auroral plasma for EmEC instability

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Communications in Theoretical Physics 2021年第1期73卷 78-86页

作者： m nazeer m n s Qureshi C shen Department of Physics GC UniversityLahore(54000)Pakistan shenzhen Graduate school HIT CampusUniversity Town of ShenzhenShenzhen 518055China

In this paper,propagation characteristics of electromagnetic electron cyclotron(EmEC)waves based on kappa-maxwellian distribution have been investigated to invoke the interplay of the electric field parallel to the Earth’s magnetic field and auroral trapped *** dispersion relation for EmEC waves in kappa-maxwellian distributed plasma has been derived using the contribution of the parallel electric field and trapped electron *** results show that the presence of the electric field has a stimulating effect on growth rate,which is more pronounced at low values of wave *** is also observed that as the threshold value of trapped electron speed is surpassed,it dominates the effect of the parallel electric field and EmEC instability is enhanced *** electric field acts as another source of free energy,and growth can be obtained even in the absence of trapped electron drift speed and for very small values of temperature *** the present study reveals the interplay of the parallel electric field and trapped electron speed on the excitation of EmEC waves in the auroral region.

关键词： EmEC waves kappa-maxwellian distribution trapped electrons parallel electric field in aurora

Q-switched raman Fiber Laser with molybdenum Disulfide-Based Passive saturable Absorber

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Chinese Physics Letters 2016年第7期33卷 98-101页

作者： n.Hisamuddin U.n.Zakaria m.Z.Zulkifli A.A.Latiff H.Ahmad s.w.Harun Photonics research Center University of Malaya Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya Aston Institute of Photonics Technologies Aston University

we demonstrate a Q-switched raman fiber laser using molybdenum disulfide （mos2） as a saturable absorber （sA）. The sA is assembled by depositing a mechanically exfoliated mos2 onto a fiber ferrule facet before it is matched with another clean ferrule via a connector. It is inserted in a raman fiber laser cavity with a total cavity length of about 8kin to generate a Q-switching pulse train operating at 1560.2nm. A 7.7-kin-long dispersion compensating fiber with 584 ***-i km-1 of dispersion is used as a nonlinear gain medium. As the pump power is increased from 395 m w to 422 m w, the repetition rate of the Q-switching pulses can be increased from 132.7 to 137.4 kHz while the pulse width is concurrently decreased from 3.35μs to 3.03μs. The maximum pulse energy of 54.3 nJ is obtained at the maximum pump power of 422 row. These results show that the mechanically exfoliated mos2 sA has a great potential to be used for pulse generation in raman fiber laser systems.

关键词： of with sA Q-switched raman Fiber Laser with molybdenum Disulfide-Based Passive saturable Absorber is in for been that

Constraining the relativistic mean-field models from PrEX-2 data:effective forces revisited

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Chinese Physics C 2022年第9期46卷 218-231页

作者： Jeet Amrit Pattnaik r.n.Panda m.Bhuyan s.K.Patra Department of Physics Siksha'O'AnusandhanDeemed to be UniversityBhubaneswar-751030India Center of theoretical and Computational Physics Department of PhysicsUniversity of MalayaKuala Lumpur50603Malaysia Institute of Physics Sachivalya MargBhubaneswar-751005India Homi Bhabha national Institute Training School ComplexAnushakti NagarMumbai 400094India

Based on the current measurement of the neutron distribution radius(r_(n))of ^(208)Pb from the PrEX-2 data,we revisited the recently developed G3 and IOPB-I force parameters by fine-tuning some specific couplings within the relativistic mean-field(rmF)***ω-ρ-mesons coupling and theρ-meson coupling are constrained to the experimental neutron radius of^(208)Pb without compromising the bulk properties of finite nuclei and infinite nuclear matter *** modified parameter sets are applied to calculate the gross properties of finite nuclei such as binding energies,charge distributions,nuclear radii,pairing gaps,and single-particle *** root-mean-square deviations in binding energy and charge radius are estimated with respect to the available experimental data for 195 even-even nuclei,and the results compare favourably with the well-calibrated effective interactions of skyrme,Gogny and other relativistic mean-field *** pairing gap estimations for modified G3 and IOPB-I for sn isotopes are also compared with the Hartree-Fock-Bogoliubov calculation with the Gogny(D1s)*** isotopic shift and single-particle energy spacing are also calculated and compared with the experimental data for both original and modified versions of the G3 and IOPB-I parameter ***,both the modified parameter sets are used to obtain the various infinite nuclear matter observables at *** addition to these,the force parameters are adopted to calculate the properties of a high isospin asymmetry dense system such as neutron star matter and tested for validation using the constraint from Gw170817 binary neutron star merger *** tuned forces predict relatively good results for finite and infinite nuclear matter systems and the current limitation on the neutron radius from PrEX-2.A systematic analysis using these two refitted parameter sets over the nuclear chart will be communicated shortly.

关键词： relativistic mean field model binding energy charge distribution radius neutron-skin thickness PrEX-2

Zinc Oxide-Based Q-switched Erbium-Doped Fiber Laser

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Chinese Physics Letters 2017年第4期34卷 43-45页

作者： n.A.Aziz A.A.Latiff m.Q.Lokman E.Hanafi s.w.Harun Department of Electrical Engineering Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia Photonics research Centre University of Malaya Kuala Lumpur 50603 Malaysia

we demonstrate a Q-switched erbium-doped fiber laser （EDFL） using a newly developed zinc oxide- （ZnO） based saturable absorber （sA）. The sA is fabricated by embedding a prepared ZnO powder into a poly（vinyl alcohol） film. A small piece of the film is then sandwiched between two fiber ferrules and is incorporated in an EDFL cavity for generating a stable Q-switching pulse train. The EDFL operates at 1560.4nm with a pump power threshold of 11.8mw, a pulse repetition rate tunable from 22.79 to 61.43kHz, and the smallest pulse width of 7.00 μs. The Q-switching pulse shows no spectral modulation with a peak-to-pedestal ratio of 62 dB indicating the high stability of the laser. These results show that the ZnO powder has a great potential to be used for pulsed laser applications.

关键词： Zinc Oxide-Based Q-switched Erbium-Doped Fiber Laser sA ZnO

nanosecond Pulses Generation with samarium Oxide Film saturable Absorber

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Chinese Physics Letters 2019年第7期36卷 48-51页

作者： n.F.Zulkipli m.Batumalay F.s.m.samsamnun m.B.H.mahyuddin E.Hanafi T.F.T.m.n.Izam m.I.m.A.Khudus s.w.Harun Photonics Engineering Laboratory Department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Faculty of Information Technology & sciences Inti International University Perdana BBN Putra Nilai Nilai 71800 Negeri Sembilan Department of Physics University of Malaya Kuala Lumpur 50603 Malaysia Department of Physics Faculty of Science and Technology Airlangga University Surabaya Indonesia

nanosecond pulse generation is demonstrated in a mode-locked erbium-doped fiber laser(EDFL) utilizing a samarium oxide(sm2O3) film. The sm2O3 film exhibits a modulation depth of 33%, which is suitable for modelocking operation. The passively pulsed EDFL operates stably at 1569.8 nm within a pumping power from 109 to 146 m w. The train of generated output pulses has a pulse width of 356 nm repeated at a fundamental frequency of 0.97 mHz. The average output power of 3.91 m w is obtained at a pump power of 146 m w, corresponding to 4.0 nJ pulse energy. The experimental result indicates that the proposed sm2O3 saturable absorber is viable for the construction of a flexible and reliably stable mode-locked pulsed fiber laser operating in the 1.5 m region.

关键词： nanosecond pulse generation erbium-doped fiber laser in the 1.5 m region

Performance evaluation of minimum quantity lubrication by vege-table oil in terms of cutting force,cutting zone temperature,tool wear,job dimension and surface finish in turning AIsI-1060 steel

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2006年第11期7卷 1790-1799页

作者： KHAn m.m.A. DHAr n.r. Department of Industrial and Production Engineering Shahajalal University of Science and Technology Sylhet 3114 Bangladesh Department of Industrial and Production Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka Bangladesh

In all machining processes, tool wear is a natural phenomenon and it leads to tool failure. The growing demands for high productivity of machining need use of high cutting velocity and feed rate. such machining inherently produces high cutting temperature, which not only reduces tool life but also impairs the product quality. metal cutting fluid changes the performance of machining operations because of their lubrication, cooling and chip flushing functions, but the use of cutting fluid has become more problematic in terms of both employee health and environmental pollution. The minimization of cutting fluid also leads to economical benefits by way of saving lubricant costs and workpiece/tool/machine cleaning cycle time. The concept of minimum quantity lubrication (mQL) has been suggested since a decade ago as a means of addressing the issues of environmental intru- siveness and occupational hazards associated with the airborne cutting fluid particles on factory shop floors. This paper deals with experimental investigation on the role of mQL by vegetable oil on cutting temperature, tool wear, surface roughness and dimen- sional deviation in turning AIsI-1060 steel at industrial speed-feed combinations by uncoated carbide insert. The encouraging results include significant reduction in tool wear rate, dimensional inaccuracy and surface roughness by mQL mainly through reduction in the cutting zone temperature and favorable change in the chip-tool and work-tool interaction.

关键词： minimum quantity lubrication (mQL) Cutting force Chip-tool interface temperature Tool wear surface roughness Dimensional deviation

numerical investigation of transonic flow over deformable airfoil with plunging motion

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Applied mathematics and mechanics(English Edition) 2016年第1期37卷 75-96页

作者： n.nEKOUBIn m.r.H.nOBArI Department of mechanical Engineering Amirkabir University of Technology

In this article, the transonic inviscid flow over a deformable airfoil with plunging motion is studied numerically. A finite volume method based on the roe scheme developed in a generalized coordinate is used along with an arbitrary Lagrangian-Eulerian method and a dynamic mesh algorithm to track the instantaneous position of the airfoil. The effects of different governing parameters such as the phase angle, the deformation amplitude, the initial angle of attack, the flapping frequency, and the mach number on the unsteady flow field and aerodynamic coefficients are investigated in detail. The results show that maneuverability of the airfoil under various flow conditions is improved by the deformation. In addition, as the oscillation frequency of the airfoil increases, its aerodynamic performance is significantly improved.

关键词： transonic flow inviscid flow fluid-solid interaction deformable airfoil,plunge motion roe scheme

Diversifying resistance mechanisms in Cereal Crops Using microphenomics

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Plant Phenomics 2023年第1期5卷 1-5页

作者： Peter m.Dracatos stefanie Lück Dimitar K.Douchkov Department of Animal Plant and Soil SciencesAgriBioLa Trobe UniversityBundooraVIC 3086Australia Leibniz Institute of Plant Genetics and Crop Plant research(IPK)Gatersleben Corrensstrasse 306466 Seeland OT GaterslebenGermany

hole-grain cereals,including wheat,barley,oat,rye,corn,rice,millet,and triticale,are a rich source of calories,essential vitamins,minerals,and phytochemicals that both nourish and protect humans and animals from diseases such as heart attack and cancer[1].However,susceptibility to foliar diseases caused by necrotrophic or biotrophic fungal pathogens continues to reduce yield potential or lead to total crop failure and famine in developing nations[2].Historically,foliar diseases of cereals have been controlled using either fungicide treatment[3]or plant breeding[4].

关键词： breeding cereal corn

A review of the Dynamic modeling Approaches for Characterizing Fluid Flow in naturally Fractured reservoirs

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Energy Engineering 2021年第4期118卷 761-795页

作者： m.n.Tarhuni w.r.sulaiman m.Z.Jaafar m.milad A.m.Alghol school of Chemical and Energy Engineering Universiti Teknologi MalaysiaSkudaiJohor81310Malaysia

Fluid flow in fractured media has been studied for decades and received considerable attention in the oil and gas industry because of the high productivity of naturally fractured *** to formation complexity and reservoir heterogeneity,characterizing fluid flow with an appropriate reservoir model presents a challenging task that differs relatively from homogeneous conventional reservoirs in many aspects of view,including geological,petrophysical,production,and *** most fractured reservoirs,fracture networks create complex pathways that affect hydrocarbon flow,well performance,hence reservoir characterization.A better and comprehensive understanding of the available reservoir modeling approaches is much needed to accurately characterize fluid flow behavior in ***,in this paper,a perspective review of the available modeling approaches was presented for fluid flow characterization in naturally fractured *** methods were evaluated in terms of their description,application,advantages,and *** study has also included the applications of these reservoir models in fluid flow characterizing studies and governing equations for fluid *** continuum models were proved to be better than single continuum models in the presence of large scale *** comparison,discrete models were more appropriate for reservoirs that contain a smaller number of ***,hybrid modeling was the best method to provide accurate and scalable fluid flow *** is our understanding that this paper will bridge the gap between the fundamental understanding and application of nFrs modeling approaches and serve as a useful reference for engineers and researchers for present and future applications.

关键词： naturally fractured reservoirs simulation techniques fluid flow modeling heterogeneity dual continuum modeling discrete fracture network modeling