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Electron Paramagnetic Resonance and Optical Absorption of VO2+Doped Ammonium Selenate Single Crystals

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Chinese Physics Letters 2011年第3期28卷 203-206页

作者： ram Kripal Ashutosh Kumar Shukla Department of Physics University of AllahabadAllahabad 211002India Department of Physics Ewing Christian CollegeAllahabad 211003India

An electron paramagnetic resonance study of vanadyl ions doped in ammonium selenate single crystals is carried out at room *** is found that the VO^(2+)ion takes up an interstitial *** spin Hamiltonian parameters obtained from the crystal rotations are g‖=1.9576±0.0002,g⊥=1.9889±0.0002,A‖=203±2 G,A⊥=78±2 *** optical absorption study is also carried out to evaluate various bonding *** the basis of these parameters the nature of bonding in the complex is discussed.

关键词： temperature parameters bonding

High universality of matK primers for barcoding gymnosperms

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Journal of Systematics and Evolution 2011年第3期49卷 169-175页

作者： ram C.POUDEL Alan FORREST Key Laboratory of Biodiversity and Biogeography Kunming Institute of BotanyChinese Academy of Sciences Germplasm Bank of Wild Species in Southwest China Kunming Institute of BotanyChinese Academy of Sciences The Graduate University of Chinese Academy of Sciences Royal Botanic Garden Edinburgh

DNA barcoding is a tool to provide rapid and accurate taxonomic identification using a standard DNA region.A two-marker combination of matK+rbcL was formally proposed as the core barcode for land plants by the Consortium for the Barcode of Life Plant Working ***,there are currently no barcoding primers for matK showing high universality in *** used 57 gymnosperm species representing 40 genera,11 families and four subclasses to evaluate the universality of nine candidate matK primers and one rbcL primer in this ***(1F/724R) of rbcL is proposed here as a universal primer for gymnosperms due to high *** of the nine candidate matK primers(GymF1A/GymR1A) is proposed as the best "universal" matK primer for gymnosperms because of high polymerase chain reaction success and routine generation of high quality bidirectional sequences.A specific matK primer for Ephedra was newly designed in this study,which performed well on the sampled *** primers proposed here for rbcL and matK can be easily and successfully amplified for most gymnosperms.

关键词： DNA barcoding matK gymnosperm primer universality.

Laboratory investigation on damping characteristics of homogeneous and stratified soil-ash system

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第10期15卷 2757-2777页

作者： Amit Kumar ram Supriya Mohanty Department of Civil Engineering Indian Institute of Technology(BHU)VaranasiVaranasi221005India

In this study,the damping responses of uniform soil,equi-proportional fly ash,and local soil as a single unit were *** large-strain cyclic triaxial tests were performed for the specimen compacted at the desired density(95%e99%of maximum dry density).The compacted specimens were tested under the loading frequency of 0.3e1 Hz with medium confinement of 70e100 ***,the unsymmetrical behavior of the hysteresis loop was analyzed using three different damping estimation approaches,*** hysteresis loop(SHL),asymmetric hysteresis loop(ASHL),and the modified American Society for Testing and materials(ASTM)*** outcome of the study shows for fly ash,local soil,and layered soil-ash,the ASHL technique has the highest damping value,followed by ASTM and then the SHL *** specimens prepared under high density and subjected to high confinement show low damping ***,the specimens tested at high frequency exhibits high damping ***,the damping value of fly ash determined using the SHL and ASHL methods has a similar profile and reaches a maximum at 1%shear strain value before *** composite stratified deposit exhibits more dependency on relative compaction,confining pressure,and less on loading *** on the results,it is highly recommended to use the ASHL approach,especially under large strain conditions irrespective of soil *** maximum damping ratio of stratified deposits is always in between the damping ratio of local soil and fly *** damping ratio of stratified soil and local soil is slightly larger than that of the other soils,although the damping ratio of fly ash is equivalent to that of the sand and clayey *** results may be helpful in the accurate determination of the damping properties of the layered soil-ash system that is required in the seismic response analysis.

关键词： Homogeneous soil Stratified soil-ash system Damping behavior Cyclic triaxial test Asymmetric hysteresis loop Model fitting

Synthesis and characterization of rare earth metal doped tungsten trioxide photocatalyst for degradation of Rhodamine B dye

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Journal of Rare Earths 2023年第9期41卷 1302-1310,I0002页

作者： pooja Nehra Amita Khatri Anil Kumar Satyendra Singh Pawan S.Rana Department of Physics Deenbandhu Chhotu Ram University of Science and TechnologyMurthal1339SonipatHaryanaIndia Special Centre for Nanoscience Jawaharlal Nehru University New Delhi10067India

Nowadays,it is concern for researchers that due to high recombination rate of photogenerated charge carriers in tungsten trioxide(WO_(3)) nanoparticles,the future applications are limited in the field of *** we attempt to synthesize tungsten trioxide nanoparticles with different doping concentrations of lanthanum i.e.2 wt%,4 wt%,6 wt% and 8 wt%.The synthesized samples were characterized by using various characterization techniques:X-ray diffraction(XRD),raman spectroscopy,Fourier transform infrared spectroscopy(FTIR),photoluminescence spectra(PL),transmission electron microscopy(TEM),energy dispersive X-ray(EDX) and UV-Vis ***_(3) retains its monoclinic structure even after doping which was confirmed by XRD *** helps to descry functional groups present in the *** size of nanoparticles was calculated by using *** confirms the absence of any impurity in the synthesized *** spectroscopy confirms the presence of a large number of imperfections induced in the lattice of WO_(3).The rate of recombination was analyzed by photoluminescence(PL) spectroscopy and is minimum in 4 wt% doping of *** optical bandgap was calculated using UV-Vis spectroscopy and becomes narrow along with the doping ***,it is found that doping of La in WO_(3) has considerably ameliorate the photocatalytic activity by reducing rate of recombination due to the trapping of electrons by defects introduced in the *** decolorization of Rhodamine B(RhB) dye was performed and the values of c/c_0 and rate constant(k) confirm that the 4 wt% doping shows maximum degradation *** kinetic study for photodegradation of Rhodamine B was done by using various kinetic models and results show that the reaction follows first order kinetics very ***,optimum doping of lanthanum increases the decolorization ability of WO_(3) towards RhB dye.

关键词： Photocatalytic activity WO_(3)nanoparticles Rhodamine B dye Rare earth doping Visible light

Solution of the Center Problem for a Class of Polynomial Differential Systems

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Acta mathematica Sinica,English Series 2024年第7期40卷 1685-1696页

作者： Chang Jian Liu Jaume Llibre Rafael ramírez Valentín ramírez School of mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai519086P.R.China Departament de matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain Departament d’Enginyeria Informàtica i matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Consider the polynomial differential system of degree m of the form x=-y(1+μ(a_(2)x-a_(1)y))+x(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),y=x(1+μ(a_(2)x-a_(1)y))+y(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),whereμandνare real numbers such that(μ^(2)+v^(2))(μ+v(m-2))(a_(1)^(2)+a_(2)^(2))≠m>2 andΩ_(m−1)(x,y)is a homogenous polynomial of degree m−1.A conjecture,stated in *** Equations 2019,suggests that whenν=1,this differential system has a weak center at the origin if and only if after a convenient linear change of variable(x,y)→(X,Y)the system is invariant under the transformation(X,Y,t)→(−X,Y,−t).For every degree m we prove the extension of this conjecture to any value ofνexcept for a finite set of values ofμ.

关键词： Center problem polynomial differential system

Optimal Design of Splitters Attached to Turbo Blower Impeller by RSM

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Journal of Thermal Science 2012年第3期21卷 215-222页

作者： Choon-man Jang Ka-ram Choi Environmental Engineering Research Division Korea Institute of Construction Technology

This paper describes the optimization of the impeller having splitters for a turbo *** design variables,chord of splitter and pitch of splitter,are introduced to enhance the blower *** pressure and ef-ficiency are selected as an object function,and the optimization of the blower impeller is performed by a response surface method (RSM).Three-dimensional Navier-Stokes equations are introduced to analyze the internal flow of the blower and to find the value of the object function for each *** the shape optimization of the splitters attached to the impeller in the turbo blower,pressure and efficiency at the design flow condition are suc-cessively increased by 5.9 percent and 17.9 percent respectively based on the reference *** higher blower efficiency obtained by optimization of impeller having splitters is mainly caused by reducing the number of im-peller blades and optimal design of splitters in the blade passage while pressure increase keeps almost the same with the reference *** the object function of pressure,pressure increase is obtained at the design and off-design conditions while efficiency keeps higher compared to the reference *** enhancement of blow-er performance is due to the reduction of reverse and circulation flows in the blade passage.

关键词： Turbo Blower Splitter Numerical Simulation Optimal Design Pressure Response Surface Method

The potential of legume-derived proteins in the food industry

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Grain & Oil Science and Technology 2022年第4期5卷 167-178页

作者： Neta Goldstein ram Reifen The Institute of Biochemistry and Nutrition The Robert H.Smith Faculty of AgricultureFood and EnvironmentThe Hebrew University of JerusalemRehovot 76100Israel

Legume-derived proteins present an opportunity to replace existing animal-source protein in various applications. Those proteins are abundant, relatively lowcost, sustainable, not highly allergenic, and widely acceptable by consumers. In this paper, it was found that legume-derived protein’s technofunctional properties(e.g. gelation, emulsification and foaming) are being investigated, in order to assess their ability to substitute for animal-derived proteins in food systems and applications. This paper reviewed the functional attributes of legume-derived proteins, their possible applications in food systems, and their potential in the food industry. The techno-functional properties of the proteins vary among different legumes, and while some proteins properties are sufficient for industrial uses, the other may need to be modified. It was concluded that legume-derived proteins could replace some existing animal-derived protein based food systems.

关键词： Legumes Plant protein Food industry Techno-functional properties Fat and protein composition

Spatial analysis and structure of a cross-timber stand in the TallGrass Prairie Preserve (Pawhuska, Oklahoma)

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Journal of Forestry Research 2013年第1期24卷 47-52页

作者： José ramón Arévalo Departamento de Ecología Facultad de BiologíaUniversidad de La LagunaLa Laguna 38206Spain

I analyzed the spatial distribution and structure of trees in a cross timber forest in the Tallgrass Prairie Preserve （Pawhuska, Oklahoma, USA）. I mapped and measured diameter of all stems, saplings （〉1.5 m tall） and dead trees in a 4-ha plot. The stand was dominated by Quercus stellata and Q. marilandica. In total, I mapped 7,636 trees, consisting of 6,785 Q. stellata, 846 Q. marilandica, 2 Celtis occidentalis, 1 Fraxinus pensilvanica and 2 Prunus americana. For saplings, I mapped 54 Q. stellata and 21 Q. marilandica. The size class distribution of the two dominant species did not differ. The dominant mortality class was “standing dead”, while I only found saplings less than 2 m tall. The spatial distribution of the species indicated segregation in the use of the environment, generating a clumped univariate distribution of stems of the same species within radii of 30 m, but repulsion outside 30 m. This segregation can be explained by the different ecological requirements of each species.

关键词： conservation point pattern analysis Quercus stellata Q.marilandica size class distribution

Regularized luni-solar gravity dynamics on resident space objects

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Astrodynamics 2021年第2期5卷 91-108页

作者： Harishkumar Sellamuthu ram Krishan Sharma Agnikul Cosmos Private Limited Indian Institute of Technology MadrasChennai600036India Department of Aerospace Engineering Karunya Institute of Technology and SciencesCoimbatore641114India

Resident space object population in highly elliptical high perigee altitude(>600 km)orbits is significantly affected by luni-solar *** regularization,an analytical orbit theory with luni-solar gravity effects as third-body perturbations in terms of Kustaanheimo-Stiefel regular elements is *** tests with different cases resulted in good accuracy for both short-and long-term orbit *** is observed that the luni-solar perturbations affect the accuracy of the analytical solution *** analytical theory is tested with the observed orbital parameters of the few objects in highly elliptical *** analytical evolution of osculating perigee altitude is found to be concurrent with observed *** perturbation,when compared with lunar perturbation,is established to be dominant over such orbits.

关键词： luni-solar perturbations regularization Kustaanheimo-Stiefel(KS)transformation