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charge self-trapping in two strand biomolecules:Adiabatic polaron approach

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chinese Physics B 2023年第1期32卷 253-263页

作者： D chevizovich S Zdravković A v chizhov Z Ivić University of Belgrade Vinča Institute of Nuclear SciencesP.O.Box 522Belgrade 11001Serbia Joint Institute for Nuclear Research Laboratory for Radiation BiologyDubna 141980Russia Dubna State University Dubna 141980Russia Department of Physics University of CreteP.O.Box 2208Heraklion 71003Greece National University of Science and Technology MISiS Leninsky prosp.4Moscow 119049Russia

We investigate the properties of the excess charge(electron, hole) introduced into a two-strand biomolecule. We consider the possibility that the stable soliton excitation can be formed due to interaction of excess charge with the phonon subsystem. The influence of overlap of the molecular orbitals between adjacent structure elements of the macromolecular chain on the soliton properties is discussed. Special attention is paid to the influence of the overlapping of the molecular orbitals between structure elements placed on the different chains. Using the literature values of the basic energy parameters of the two-chain biomolecular structures, possible types of soliton solutions are discussed.

关键词： charge self-trapping adiabatic polaron soliton two-stranded biomolecules

Polarized Ketene Dithioacetals-versatile Synthons for Different Heterocycles

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chinese Journal of chemistry 2012年第8期30卷 1886-1892页

作者： venkatesh B.c. Premakumari c. Padmaja A. Padmavathi v. Department of chemistry Sri Venkateswara UniversityTirupati-517502Andhra PradeshIndia

The reactivity of polarized ketene dithioacetals to develop a variety of heterocycles under different conditions was studied.

关键词： polarized ketene dithioacetals thienothiophenes bis-benzoxazolyl/benzothiazolyl/benzimidazolyl-pyrazolidine diones/isoxazolidinediones/pyrimidinetriones/thioxopyrimidinediones cyclocondensation

Biomass Industrial Effluent Effect on carbohydrates,Aminoacids,Nitrite and Nitrite Enzyme Activities of Arachis hypogaea L.

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Agricultural Sciences in china 2009年第2期8卷 203-215页

作者： P c Nagajyoti N Dinakar S Suresh Y Udaykiran c Suresh T N v K v Prasad T Damodharam Department of Environmental Sciences Sri Venkateswara University National Institute of Nutrition Hyderabad Regional Agricultural Research Station N.G. Ranga Agriculture University

The objectives of the present investigations are to see the effects of biomass power plant effluent on the carbohydrates, aminoacids, nitrite and nitrite enzyme activitiesand proline of Arachis hypogaea L. var TcGS 320 under controlled pot culture methods. Plants were cultivated with 25, 50, 75 and 100% of the effluent and a control without the effluent. The treatment of the crop with 25% of the effluent has shown stimulatory effect on all the biochemical parameters studied. carbohydrates, starch, aminoacids, protein, nitrate and nitrite reductase enzymatic activities have increased in 10, 15, 20 DAS （days after sowing）. In 25 and 30 DAS all biochemical parameters have decreased, due to environmental factors （rainfall, temperature, humidity, etc.）. The present investigation clearly indicated that the biomass power plant effluent has stimulatory effect on all the biochemical contents at lower concentration, and at higher concentration they have deleterious effects.

关键词： biomass power plant effluent biochemical parameters Arachis hypogaea stimulatory effect

Effect of retained austenite and nonmetallic inclusions on the thermal/electrical properties and resistance spot welding nuggets of Si-containing TRIP steels

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 52-63页

作者： v.H.vargas I.Mejía v.H.Baltazar-Hernández c.Maldonado Metallurgy and Materials Research Institute Universidad Michoacana de San Nicolás de Hidalgo Edificio "U" Ciudad Universitaria Materials Science and Engineering Program Autonomous University of Zacatecas

Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, c, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets.

关键词： transformation-induced plasticity steel retained austenite non-metallic inclusions magnetic saturation electrical properties thermal properties resistance spot welding nugget

Flash X-ray radiography technique to study the high velocity impact of soft projectile on E-glass/epoxy composite material

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Defence Technology（防务技术） 2019年第2期15卷 216-226页

作者： B.venkata Ramudu c.Jayarami Reddy v.Madhu Armour Design and Development Division Defence Metallurgical Research Laboratory

In the present paper, the high velocity impact of 9 mm soft lead projectile on 10 mm and 30 mm thick Eglass/epoxy composites was studied using a 450 kv Flash X-ray radiography(FXR) system. The basic parameters of FXR imaging, such as effect of ratio of target to film(TF) and source to target(ST) distances and X-ray penetration thickness of the composite material were optimized based on clarity and the actual dimensions of the objects. The optimized parameters were used in the FXR imaging of the ballistic event of 9 mm soft projectile on E-glass/epoxy composite. The real time deformation patterns of both the projectile and composite target during the ballistic impact were captured and studied at different time intervals. The notable failure modes of the 10 mm thick target with time include fibre breakage, bulging on the back side, delamination, recovery of the bulging, reverse bulging and its recovery. However, with increase in thickness of the target to 30 mm the only failure mechanism observed is the breaking of fibres. The ballistic impact event was also numerically simulated using commercially available LS-DYNA software. The numerically simulated deformation patterns of the projectile and target at different time intervals are closely matching with the corresponding radiographic images.

关键词： Flash X-ray radiography E-Glass/epoxy composite Ballistic impact Numerical simulation

Spectroscopic and fluorescence properties of Sm^(3+)-doped zincfluorophosphate glasses

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Journal of Rare Earths 2014年第10期32卷 918-926页

作者： v.B.Sreedhar ch.Basavapoornima c.K.Jayasankar Department of Physics Sri Venkateswara University Department of Physics National Degree and P.G. College

Optical absorption and fluorescence spectra of Sm3＋-doped zincfluorophosphate glasses with molar composition of 44P2O5＋17K20＋9Al2O3＋（30-χ）ZnF2＋χSm2O3 （χ=0.01 mol.%, 0.05 mol.%, 0.1 mol.%, 0.5 mol.%, 1.0 mol.%, 2.0 and 3.0 mol.%） referred as PKAZFSm were prepared by melt quenching technique and were characterized through Raman, absorption, emission and decay curve analysis. From the absorption spectra, Judd-Ofelt intensity parameters were determined and were used to predict radiative properties such as transition probabilities （AR, radiative lifetimes （τR）, branching ratios （βR）, effective bandwidths （△λeff） and stimulated emission cross-section （σ（λp）） for the excited 4G5/2 luminescent level. The decay curve for the 4G5/2 level was single exponential for lower concentration and became non-exponential for higher concentrations. The non-exponential nature of the decay curves of the 4G5/2 level increased with increase in Sm3＋ ions concentration accompanied by decrease in lifetime due to energy transfer processes among the Sm3＋ ions. The non-exponential decay curves was well fitted to the generalized Inokuti-Hirayama model for S=6, indicating that the energy transfer among optically active ions was of dipole-dipole interaction. The cross-relaxation mechanism responsible for the quenching of lifetimes and the effect of variation of concentration on the spectroscopic properties were also discussed.

关键词： zincfluorophosphate glasses samarium Raman spectrum optical properties fluorescence properties rare earths

Provenance bias between detrital zircons from sandstones and river sands:A quantification approach using 3-D grain shape,composition and age

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Geoscience Frontiers 2020年第3期11卷 835-842页

作者： v.Markwitz c.L.Kirkland K.Gessner School of Earth Sciences The University of Western AustraliaWA6009Australia School of Earth and Planetary Science Centre for Exploration Targeting-Curtin NodeCurtin UniversityWA6045Australia Geological Survey of Western Australia 100 Plain StreetEast PerthWA6004Australia

Preservation bias may significantly impact the application of detrital zircon geochronology in reconstructing Earth surface *** we compare detrital zircons from the actively eroding Murchison River channel in Western Australia with Ordovician fluvial sediments that have drained similar source rocks along the western margin of the West Australian *** addition to standard analysis of detrital zircon age spectra we apply multivariate statistics to test the relation between 3-D grain shape,U-content and U-Pb ages,with the objective to quantify differences between both sample groups and track preservation along the transport pathway of the Murchison *** results show that zircon grains in modern river sands display an upstream trend toward larger surface areas,volume equivalent diameters and grain widths,as well as toward higher U-contents and lower apparent grain densities.3-D grain shape,size and age spectra of Murchison River zircons evolve consistently downstream,but even at the river outlet remain distinct from the Ordovician samples,as a less mature representation of *** interpret Ordovician river zircons to represent a significantly depleted subset from which up to 22% of the zircon population may have been lost compared to the actively transported detrital *** discrepancy between the characteristics of detrital zircons in modern active rivers and ancient fluvial Ordovician sandstones demonstrates a bias that could be relevant for other source-sink detrital transport systems throughout Earth history.

关键词： X-ray tomography Detrital Zircon Grain shape Preservation Fluvial

Harnessing a multi-dimensional fibre laser using genetic wavefront shaping

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Light(Science & Applications) 2020年第1期9卷 593-602页

作者： Xiaoming Wei Joseph c.Jing Yuecheng Shen Lihong v.Wang caltech Optical Imaging Laboratory Andrew and Peggy Cherng Department of Medical EngineeringDepartment of Electrical EngineeringCalifornia Institute of Technology1200 East California Boulevard MailCode 138-78Pasadena 91125 CAUSA School of Physics and Optoelectronics/State Key Laboratory of Luminescent Materials and Devices/Guangdong Engineering Technology Research and Development center of Special Optical Fiber Materials and Devices/Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques South China University of Technology381 Wushan RoadGuangzhou 510640China School of Electronics and Information Technology Sun Yatsen UniversityGuangzhou 510006China

The multi-dimensional laser is a fascinating platform not only for the discovery and understanding of new higherdimensional coherent lightwaves but also for the frontier study of the complex three-dimensional(3D)nonlinear dynamics and solitary waves widely involved in physics,chemistry,biology and materials *** controlling coherent lightwave oscillation in multi-dimensional lasers,however,is challenging and has largely been unexplored;yet,it is crucial for both designing 3D coherent light fields and unveiling any underlying nonlinear ***,for the first time,we genetically harness a multi-dimensional fibre laser using intracavity wavefront shaping technology such that versatile lasing characteristics can be *** demonstrate that the output power,mode profile,optical spectrum and mode-locking operation can be genetically optimized by appropriately designing the objective function of the genetic *** is anticipated that this genetic and systematic intracavity control technology for multi-dimensional lasers will be an important step for obtaining high-performance 3D lasing and presents many possibilities for exploring multi-dimensional nonlinear dynamics and solitary waves that may enable new applications.

关键词： fibre dimensional coherent

Atomic Processes in Emission characteristics of a Lithium Plasma Plume Formed by Double-Pulse Laser Ablation

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Plasma Science and Technology 2013年第3期15卷 204-208页

作者： v.SIvAKUMARAN AJAI KUMAR R.K.SINGH v.PRAHLAD H.c.JOSHI Institute for Plasma Research

High resolution spectral analysis of lithium plasma formed by single and double laser ablation has been undertaken to understand the plume-laser interaction, especially at the early stages of the plasma plume. In order to identify different atomic processes in evolving plasma, time resolved spectral emission studies at different inter-pulse delays have been performed for ionic and neutral lithium lines emitting from different levels. Along with the enhancement in emission intensity, a large line broadening and spectral shift, especially in the case of excited state transition Li I 610.3 nm have been observed in the presence of the second pulse. This broadening and shift gradually decrease with increasing time delay. Another interesting feature is the appearance of a multi-component structure in the ionic line at 548.4 nm and these components change conversely into a single structure at the later stages of the plasma. The multi-component structures are correlated with the presence of different velocity （temperature） distributions in non-LTE conditions. Atomic analyses by computing photon emissivity coefficients with an ADAS code have been used to identify the above processes.

关键词： laser ablation double pulse