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Journal of Environmental Science and Engineering 2011年第9期5卷 1147-1154页

作者： m. rashidi m. Seilsepour Department of mechanical Engineering East Tehran Branch Islamic Azad University Tehran Iran Department of Soil and Water Research Tehran Province Agricultural and Natural Resources Research Center Varamin Iran

Nitrogen （N） was applied at rates of 0, 100, 200 and 300 ***^-1 and boron （B） was applied as foliar at rates 0, 500 and 1000 ***^-1 to study the effect of different application rates of nitrogen and boron fertilizers on yield, yield components and fiber properties of cotton. Statistical results of study showed that N application significantly （P 〈 0.05） enhanced boll number, boll weight, seed cotton weight of boll, seed cotton yield and lint yield. Results of study also indicated that the maximum seed cotton yield was recorded in case of 200 ***^-1 N application rate, and this application rate resulted in 19.6% increased seed cotton yield. Statistical results also indicated that foliar application of B significantly enhanced boll number, boll weight, seed cotton yield and lint yield. Results also demonstrated that the maximum seed cotton yield was obtained in case of 1000 *** foliar application of B, and this foliar application rate resulted in 25% increased seed cotton yield. Statistical results showed that effect of different application rates of N was not significant for all fiber properties （fiber length, fiber strength and fiber fineness）. Conversely, results of study indicated that different application rates of B significantly affected some fiber properties.

关键词： Nitrogen boron cotton yield yield components fiber properties Iran.

Structural, elastic and electronic properties for m_2 XC (m=Ti and Cr, X=Ga and Al) phases from ab initio calculations

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Acta metallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli m.A. Ghebouli m. Fatmi N. Bouarissa m. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids materials Department of Physics Faculty of Science University of Setif Department of Physics University Center Research Unit on Emerging materials Ferhat Abbas University of Setif Department of Physics Faculty of Sciences King Khalid University Central metallurgical Research and Development Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m2XC phases depending on the type of m transition metal （m are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are performed using the pseudo-potential plane-wave approach in both the local density and generalized gradient approximations. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic parameters, Debye tem- perature, sound velocities and their pressure dependence have been investigated. In agreement with experimental and previous theoretical findings, it is found that the compressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and m elements on the machinability indices of the material have been examined. The electronic properties have been discussed in terms of chemical bonding showing that bonding is due to md-Cp and md-Xp hybridizations. m-C bonds are stiffer than m-X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m-X and m-C bonds increases with increasing the number of VEC.

关键词： m2XC phases ab initio Pressure effect Band structures

Influence of FCA Welding Process Parameters on Distortion of 409m Stainless Steel for Rail Coach Building

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Journal of Iron and Steel Research International 2013年第1期20卷 71-78页

作者： m V Venkatesan N murugan B m Prasad A manickavasagam Department of mechanical Engineering Coimbatore Institute of TechnologyCoimbatore 641014TNIndia Integral Coach Factory Indian RailwaysChennai 600038TNIndia

The influence of flux cored arc welding （FCAW） process parameters such as welding current, travel speed, voltage and CO2 shielding gas flow rate on bowing distortion of 409m ferritic stainless steel sheets of 2 mm in thickness was discussed. The bowing distortions of the welded plates were measured using a simple device called profile tracer. An experimental regression equation was developed to predict the bowing distortion and with this equation, it is easy to select optimized process parameters to achieve minimum bowing distortion. It is revealed that the FCAW process parameters have significant influence on bead profile and the bowing distortion.

关键词： bowing distortion ferritic stainless steel flux cored arc welding statistical model rail coach distortion measurement

Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily Firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow matthew F.Gary Ali m.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

Holmium Oxide Film as a Saturable Absorber for 2μm Q-Switched Fiber Laser

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Chinese Physics Letters 2017年第5期34卷 48-51页

作者： m.F.A.Rahman m.F.m.Rusdi m.Q.Lokman m.B.H.mahyuddin A.A.Latiff A.H.A.Rosol K.Dimyati S.W.Harun Department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Photonics Research Centre University of Malaya Kuala Lumpur 50603 Malaysia Faculty of Electrical Engineering University Teknologi Mara Shah Alam 40450 Malaysia

This work reports on the use of the holmium oxide （Ho2O3） polymer film as a saturable absorber （SA） for generating stable Q-switching pulses operating in a 2μm region in a thulium-doped fiber laser cavity. The SA is prepared by diluting a commercial Ho3O2 powder and then mixing it with polyvinyI alcohol （PVA） solution to form a Ho2O3-PVA film. A tiny part of the film about 1mm×1 mm in size is sandwiched between two fiber ferrules with the help of index matching gel. When incorporated in a laser cavity driven by a 1552-nm pump, stable Q-switching pulses are observed at 1955nm within the pump power range of 363 491 roW. As the pmnp power increases within this range, the repetition rate rises from 26 kHz to 39 kHz, as the pulse width drops from 4.22μs to 2.57μs. The laser operates with a signal-to-noise ratio of 47dB, and the maximum output power and the pulse energy obtained are 2.67mW and 69ng, respectively. Our results successfully demonstrate that the Ho2O3 film can be used as a passive SA to generate a 2μm pulse laser.

关键词： m Q-Switched Fiber Laser SA FESEm

Charaeterizability of the Group ~2D_p(3) by its Order Components,Where p≥5 is a Prime Number Not of the Form 2~m+1

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Acta mathematica Sinica,English Series 2008年第7期24卷 1117-1126页

作者： m.R.DARAFSHEH School of mathematics College of ScienceUniversity of TehranTehranIran

The author will prove that the group ^2Dp（3） can be uniquely determined by its order components, where p ≠ 2^m ＋ 1 is a prime number, p ≥ 5. more precisely, if OC（G） denotes the set of order components of G, we will prove OC（G） = OC（^2Dp（3）） if and only if G is isomorphic to ^2Dp（3）. A main consequence of our result is the validity of Thompson＇s conjecture for the groups under consideration.

关键词： prime graph order component linear group

Application of multi-Step Differential Transform method on Flow of a Second-Grade Fluid over a Stretching or Shrinking Sheet

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American Journal of Computational mathematics 2011年第2期1卷 119-128页

作者： m.m.rashidi Ali J. Chamkha m Keimanesh 不详

In this study, a reliable algorithm to develop approximate solutions for the problem of fluid flow over a stretching or shrinking sheet is proposed. It is depicted that the differential transform method (DTm) solutions are only valid for small values of the independent variable. The DTm solutions diverge for some differential equations that extremely have nonlinear behaviors or have boundary-conditions at infinity. For this reason the governing boundary-layer equations are solved by the multi-step Differential Transform method (mDTm). The main advantage of this method is that it can be applied directly to nonlinear differential equations without requiring linearization, discretization, or perturbation. It is a semi analytical-numerical technique that formulizes Taylor series in a very different manner. By applying the mDTm the interval of convergence for the series solution is increased. The mDTm is treated as an algorithm in a sequence of intervals for finding accurate approximate solutions for systems of differential equations. It is predicted that the mDTm can be applied to a wide range of engineering applications.

关键词： Non-Newtonian Fluid Stretching Surface Shrinking Sheet multi-Step Differential Transform method (mDTm)

Antimonene-based saturable absorber for a soliton mode-locked and Q-switched fiber laser in the 2 μm wavelength region

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Chinese Physics B 2023年第6期32卷 259-269页

作者： H Ahmad B Nizamani m Z Samion N Yusoff m F Ismail Photonics Research Centre Universiti Malaya50603 Kuala LumpurMalaysia Physics Department Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia Distinguished Visiting Professor Universiti Kuala Lumpur British Malaysian Institute(UniKL BMI)Batu 8Jln Sungai Pusu53100SelangorMalaysia

We demonstrate antimonene as a saturable absorber(SA) to generate an ultrafast mode-locked and Q-switched laser in the 2 μm wavelength region. The two antimonene-based SAs were prepared and inserted separately in a thulium–holmiumdoped fiber laser to produce the pulsed laser. Antimonene was coated onto a tapered fiber to generate soliton mode-locked pulses and used in thin-film form for the generation of Q-switched pulses. The mode-locking was stable within a pump power of 267 m W–511 m W, and the laser operated at a central wavelength of 1897.4 nm. The mode-locked laser had a pulse width of 1.3 ps and a repetition rate of 12.6 mHz, with a signal-to-noise ratio of 64 d B. Q-switched laser operation was stable at a wavelength of 1890.1 nm within a pump power of 312 m W–381 m W. With the increase in pump power from 312 m W to 381 m W, the repetition rate increased to a maximum of 56.63 k Hz and the pulse width decreased to a minimum value of 2.85 μs. Wide-range tunability of the Q-switched laser was also realized within the wavelength range of1882 nm–1936 nm.

关键词： mode-locking Q-switched fiber laser optical saturable absorber

One-loop approximation of mφller scattering in generalized Krein-space quantization

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Science China(Physics,mechanics & Astronomy) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. mEHRAFARIN m. V. TAKOOK Physics Department Amirkabir University of Technology Payame Noor University Physics Department Razi University

It has been shown that the negative-norm states necessarily appear in a covariant quantization of the free minimally coupled scalar field in de Sitter spacetime. In this processes ultraviolet and infrared di- vergences have been automatically eliminated. A natural renormalization of the one-loop interacting quantum field in minkowski spacetime (λφ 4) has been achieved through the consideration of the nega- tive-norm states defined in Krein space. It has been shown that the combination of quantum field theory in Krein space together with consideration of quantum metric fluctuation, results in quantum field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem and calculate mφller scattering in the one-loop approximation in generalized Krein space. The mathematical consequence of this method is the disappearance of the ultraviolet divergence in the one-loop approximation.

关键词： quantum field theory Krein space negative energy states

2D CFD Analysis and Experimental Analysis on the Effect of Hub to Tip Ratios on the Performance of 0.6 m Impulse Turbine

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Journal of Thermal Science 2004年第4期13卷 315-320页

作者： A. THAKKER m.El. HEmRY Wave Energy Research Team Department of mechanical and Aeronautical Engineering University of Limerick IrelandWave Energy Research Team Department of Mechanical and Aeronautical Engineering University of Limerick Ireland

The objective of this paper is to present the performance comparison of 2D Computational Fluid Dynamics (CFD) analysis with experimental analysis of 0.6 m impulse turbine with fixed guide vanes for both 0.6 and 0.7 hub to tip ratio (H/T). Also the comparison of 2D CFD analysis of the said turbine with different values of H/T ranging from 0.5 to 0.7. A 2D-cascade model was used for CFD analysis while uni-directional steady flow was used for experimental analysis. The blade and guide vane geometries are based on 0.6 m rotor diameter, with optimum profile, and different H/T of 0.5, 0.6 and 0.7. It was concluded from 2D CFD analysis that 0.5 H/T ratio performances was higher than that of 0.6 and 0.7 H/T at peak efficiency and the operational flow range for 0.5 H/T was found to be wider than that of 0.6 and 0.7 H/T ratio.

关键词： wave energy impulse turbine computational fluid dynamics (CFD).