Spectroscopic Study Of The Inhibition Of Calcium Oxalate Calculi By Larrea Tridentata,
2010
University of Texas at El Paso
Spectroscopic Study Of The Inhibition Of Calcium Oxalate Calculi By Larrea Tridentata, Luis Alonso Pinales
Open Access Theses & Dissertations
The causes of urolithiasis include such influences as diet, metabolic disorders, and genetic factors which have been documented as sources that aggravate urinary calculi depositions and aggregations, and, implicitly, as causes of urolithiasis. This study endeavors to detail the scientific mechanisms involved in calcium oxalate calculi formation, and, more importantly, their inhibition under growth conditions imposed by the traditional medicinal approach using the herbal extract, Larrea tridentata. The calculi were synthesized without and with Larrea tridentata infusion by employing the single diffusion gel technique. A visible decrease in calcium oxalate crystal growth with increasing amounts of Larrea tridentata herbal infusion …
Super-Resolution Using Adaptive Wiener Filters,
2010
University of Dayton
Super-Resolution Using Adaptive Wiener Filters, Russell C. Hardie
Electrical and Computer Engineering Faculty Publications
The spatial sampling rate of an imaging system is determined by the spacing of the detectors in the focal plane array (FPA). The spatial frequencies present in the image on the focal plane are band-limited by the optics. This is due to diffraction through a finite aperture. To guarantee that there will be no aliasing during image acquisiton, the Nyquist criterion dictates that the sampling rate must be greater than twice the cut-off frequency of the optics. However, optical designs involve a number of trade-offs and typical imaging systems are designed with some level of aliasing. We will refer to …
Characterization Of Atmospheric Turbulence Effects Over 149 Km Propagation Path Using Multi-Wavelength Laser Beacons,
2010
University of Dayton
Characterization Of Atmospheric Turbulence Effects Over 149 Km Propagation Path Using Multi-Wavelength Laser Beacons, Mikhail Vorontsov, Gary W. Carhart, Venkata S. Rao Gudimetla, Thomas Weyrauch, Eric Stevenson, Svetlana Lachinova, Leonid A. Beresnev, Jony Jiang Liu, Karl Rehder, Jim F. Riker
Electrical and Computer Engineering Faculty Publications
We describe preliminary results of a set of laser beam propagation experiments performed over a long (149 km) near-horizontal propagation path between Mauna Loa (Hawaii Island) and Haleakala (Island of Maui) mountains in February 2010. The distinctive feature of the experimental campaign referred to here as the Coherent Multi-Beam Atmospheric Transceiver (COMBAT) experiments is that the measurements of the atmospheric-turbulence induced laser beam intensity scintillations at the receiver telescope aperture were obtained simultaneously using three laser sources (laser beacons) with different wavelengths (λ1 = 0.53 μm, λ2 = 1.06 μm, and λ3 = 1.55 μm). The presented experimental results on …
Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel,
2010
Old Dominion University
Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel, Ye Ai, Shizhi Qian, Sheng Liu, Sang W. Joo
Mechanical & Aerospace Engineering Faculty Publications
Experiments show that particles smaller than the throat size of converging-diverging microchannels can sometimes be trapped near the throat. This critical phenomenon is associated with the negative dc dielectrophoresis arising from nonuniform electric fields in the microchannels. A finite-element model, accounting for the particle-fluid-electric field interactions, is employed to investigate the conditions for this dielectrophoretic (DEP) choking in a converging-diverging microchannel for the first time. It is shown quantitatively that the DEP choking occurs for high nonuniformity of electric fields, high ratio of particle size to throat size, and high ratio of particle's zeta potential to that of microchannel. © …
A Phenomenographic Study Of Introductory Physics Students: Approaches To Their Learning And Perceptions Of Their Learning Environment In A Physics Problem-Based Learning Environment,
2010
Technological University Dublin
A Phenomenographic Study Of Introductory Physics Students: Approaches To Their Learning And Perceptions Of Their Learning Environment In A Physics Problem-Based Learning Environment, Paul Irving
Doctoral
This phenomenographic study describes students’ approaches to learning and their perceptions of the learning environment in an introductory physics course which is taught using a problem-based learning approach. This research builds on previous studies which showed that these students develop a greater conceptual knowledge than their counterparts in a more traditional learning environment while others showed very little development even though they engaged fully with the pedagogy. This study aimed to examine and describe the students’ approaches to learning. The definitions of surface, strategic and deep approaches to learning are not appropriate in this context and could not be applied …
Creation Of Noon States By Double Fock-State/Bose-Einstein Condensates,
2010
University of Massachusetts Amherst
Creation Of Noon States By Double Fock-State/Bose-Einstein Condensates, Wj Mullin, F. Laloe
Physics Department Faculty Publication Series
NOON states (states of the form |N〉 a |0〉 b +|0〉 a |N〉 b where a and b are single particle states) have been used for predicting violations of hidden-variable theories (Greenberger-Horne-Zeilinger violations) and are valuable in metrology for precision measurements of phase at the Heisenberg limit. We show theoretically how the use of two Fock state/Bose-Einstein condensates as sources in a modified Mach Zender interferometer can lead to the creation of the NOON state in which a and b refer to arms of the interferometer and N is the total number of particles in the two condensates. The modification …
Lattice Dynamical Probe Of Charge Order And Antipolar Bilayer Stacking In Lufe2o4,
2010
University of Nebraska-Lincoln
Lattice Dynamical Probe Of Charge Order And Antipolar Bilayer Stacking In Lufe2o4, X. S. Xu, J. De Groot, Q.-C. Sun, B. C. Sales, D. Mandrus, M. Angst, A. P. Litvinchuk, J. L. Musfeldt
Xiaoshan Xu Papers
We investigated the infrared response of LuFe2O4 through the series of charge, magnetic, and structural transitions. All vibrational modes couple strongly to the charge order, whereas the LuO zone-folding modes are also sensitive to magnetic order and structural distortion. The dramatic splitting of the LuO2 layer mode is attributed to charge-rich/poor proximity effects and its temperature dependence reveals the antipolar nature of the W layer pattern.
Optical Properties Of Quasi-Tetragonal Bifeo3 Thin Films,
2010
University of Tennessee
Optical Properties Of Quasi-Tetragonal Bifeo3 Thin Films, P. Chen, N. J. Podraza, X. S. Xu, A. Melville, E. Vlahos, V. Gopalan, R. Ramesh, D. G. Schlom, J. L. Musfeldt
Xiaoshan Xu Papers
Optical transmission spectroscopy and spectroscopic ellipsometry were used to extract the optical properties of an epitaxially grown quasi-tetragonal BiFeO3 thin film in the near infrared to near ultraviolet range. The absorption spectrum is overall blue shifted compared with that of rhombohedral BiFeO3, with an absorption onset near 2.25 eV, a direct 3.1 eV band gap, and charge transfer excitations that are ~0.4 eV higher than those of the rhombohedral counterpart. We interpret these results in terms of structural strain and local symmetry breaking.
Permittivity And Permeability Of Fe(Tb) Nanoparticles And Their Microwave Absorption In The 2–18 Ghz Range,
2010
Shenyang National Laboratory for Materials Science, Institute of Metal Research and International Center for Materials Physics, Chinese Academy of Sciences
Permittivity And Permeability Of Fe(Tb) Nanoparticles And Their Microwave Absorption In The 2–18 Ghz Range, Z. Han, D. Li, M. Tong, X. Wei, Ralph Skomski, W. Liu, Z. D. Zhang, David J. Sellmyer
Ralph Skomski Publications
The permittivity and permeability of the Tb-doped and undoped Fe core-shell nanoparticles were investigated for frequencies from 2 to 18 GHz. The particles were synthesized by arc discharge and contain some oxygen, probably in the form of Fe2O3, Fe3O4, and Tb2O3, whereas the core material is Fe. Both the electromagnetic materials constants and the morphology of the Fe nanoparticles are changed by Tb addition, which gives rise to the shifts to higher frequencies and thinner thicknesses of the maximum microwave absorption in the Tb-doped Fe nanoparticles.
Structural, Magnetic And Magneto-Transport Properties Of Pt-Alloyed Mnbi Thin Films,
2010
University of Nebraska-Lincoln
Structural, Magnetic And Magneto-Transport Properties Of Pt-Alloyed Mnbi Thin Films, Parashu Kharel, Ralph Skomski, Roger D. Kirby, David J. Sellmyer
Ralph Skomski Publications
The structural, magnetic and magneto-transport properties of highly c-axis oriented Mn55−xPtxBi45 (x=0, 1.5, 3, and 4.5) thin films have been investigated. The coercivity of the Pt-alloyed thin films increases and the saturation magnetization decreases as the Pt concentration increases. The anisotropy field Ho increases as a function of Pt concentration, too but the coercivity increases more rapidly than the anisotropy field. This indicates an enhanced domain-wall pinning, caused by increased interstitial disorder due to the occupancy of regular Mn sites by Pt. The same mechanism explains the reduced magnetization. All samples exhibit a large …
Magnetism Of Core-Shell Ti:Tio Nanoparticles,
2010
University of Nebraska-Lincoln
Magnetism Of Core-Shell Ti:Tio Nanoparticles, Xiaohui Wei, Ralph Skomski, Balamurugan Balasubramanian, David J. Sellmyer
Ralph Skomski Publications
Ti nanoparticles were produced using a cluster-deposition method. Ti:TiO core-shell structures were fabricated by partially oxidizing the surface of the Ti nanoparticles produced by a cluster-deposition system via multistep annealing at 250 °C in oxygen. X-ray diffraction and transmission-electron microscopy studies reveal an increase in the thickness of the TiO shell with increasing annealing time. The magnetic moment and the coercivity of the core-shell nanoparticles increase with the TiO shell thickness, which is consistent with homogenous bulk defects in TiO. The core-shell nanoparticles display an abnormal hysteresis loop, which probably reflects a combination of antiferromagnetic exchange and magnetocrystalline anisotropy.
Magnetic Antiphase Domains In Co/Ru/Co Trilayers,
2010
University of Nebraska-Lincoln
Magnetic Antiphase Domains In Co/Ru/Co Trilayers, Zhen Li, Ralph Skomski, Steven A. Michalski, Lanping Yue, Roger D. Kirby
Ralph Skomski Publications
Ultrathin Co/Ru/Co trilayers are investigated experimentally by magnetization curves and magnetic-force microscopy (MFM). Emphasis is on the domain-wall fine structure of antiphase domain walls in the films. The trilayers are produced by sputtering and consist of two Co layers of equal thickness (5 nm), exchange-coupled through a Ru layer of variable thickness. The sign and magnitude of the interlayer exchange are tuned by the thickness of the Ru interlayer. The exchange and its distribution are investigated by measurements of the static magnetization curves. For a Ru thickness of 0.4 nm, the exchange is predominantly antiferromagnetic and the MFM images show …
Interstitial-Nitrogen Effect On Phase Transition And Magnetocaloric Effect In Mn(As,Si) (Invited),
2010
Shenyang National Laboratory for Materials Science, Institute of Metal Research and International Center for Materials Physics, Chinese Academy of Sciences
Interstitial-Nitrogen Effect On Phase Transition And Magnetocaloric Effect In Mn(As,Si) (Invited), W. B. Cui, X. K. Lv, F. Yang, Ralph Skomski, Y. Yu, X. G. Zhao, W. Liu, Z.D. Zhang
Ralph Skomski Publications
The effect of interstitial nitrogen on the phase transition and magnetocaloric behavior of MnAs1−xSixNδ (x=0.03, 0.06, and 0.09) is investigated. The interstitial nitrogen atoms cause the step-scanned x-ray diffraction peaks to shift toward lower angles and lower the Curie temperature, whereas silicon addition increases the Curie temperature to near room temperature. The thermal hysteresis is reduced to nearly 0 in MnAs1−xSixNδ, which is beneficial to practical applications. For a field change of 5 T, the largest magnetic entropy change and refrigerant capacity are 14.6 J kg−1 K−1 …
Studies Of Chemical Fixation Effects In Human Cell Lines Using Raman Microspectroscopy,
2010
Technological University Dublin
Studies Of Chemical Fixation Effects In Human Cell Lines Using Raman Microspectroscopy, Aidan Meade, Colin Clarke, Florence Draux, Ganesh Sockalingum, Michel Manfait, Fiona Lyng, Hugh Byrne
Articles
The in vitro study of cellular species using Raman spectroscopy has proven a powerful non-invasive modality for the analysis of cell constituents and processes. This work uses micro-Raman spectroscopy to study the chemical fixation mechanism in three human cell lines (normal skin, normal bronchial epithelium, and lung adenocarcinoma) employing fixatives that preferentially preserve proteins (formalin), and nucleic acids (Carnoy’s fixative and methanol–acetic acid). Spectral differences between the mean live cell spectra and fixed cell spectra together with principal components analysis (PCA), and clustering techniques were used to analyse and interpret the spectral changes. The results indicate that fixation in formalin …
Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics,
2010
Utah State University
Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics, Justin Koeln, Andrew Fassmann, Troy Munro, Rob Barnett
Presentations
No abstract provided.
Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics,
2010
Utah State University
Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics, Justin Koeln, Andrew Fassmann, Troy Munro, Rob Barnett
Education and Outreach
No abstract provided.
Effect Of Substrate Temperature On The Optical Properties Of Thermally Evaporated Zns Thin Films,
2010
TÜBİTAK
Effect Of Substrate Temperature On The Optical Properties Of Thermally Evaporated Zns Thin Films, M. Ruhul Amin Bhuiyan, M. Monjarul Alam, M. Abdul Momin
Turkish Journal of Physics
Zinc Sulfide (ZnS) thin films were formed onto cleaned glass substrates using the thermal evaporation method in vacuum. The substrate temperature was varied between as- deposited and 150 °C, keeping the film thickness and the rate of evaporation fixed at 200~nm and 0.3~nm \cdot s^{-1}, respectively. The film thickness was measured in situ by a quartz crystal thickness monitor. The structure of the films was ascertained by x-ray diffraction (XRD) method. The XRD spectra show that the films are polycrystalline in nature, which possess hexagonal structure. The optical properties of the films were ascertained by UV-VIS-NIR spectrophotometer (photon wavelength ranging …
Chemical Bath Deposition And Characterization Of Cu_2o-Cu_Xs Thin Films,
2010
TÜBİTAK
Chemical Bath Deposition And Characterization Of Cu_2o-Cu_Xs Thin Films, D. D. O. Eya
Turkish Journal of Physics
Cu_2O-Cu_xS thin films have been deposited on glass substrate by chemical bath deposition technique. The films were obtained by depositing Copper Sulphide (Cu_xS) on Copper (I) Oxide (Cu_2O) and then Cu_2O on Cu_xS. The peak solar transmittance across the thin films were found to be
Electron Paramagnetic Resonance Study Of Vo^{2+} Doped Single Crystal Of Ferroelectric Guanidinium Uranyl Sulphate Trihydrate,
2010
TÜBİTAK
Electron Paramagnetic Resonance Study Of Vo^{2+} Doped Single Crystal Of Ferroelectric Guanidinium Uranyl Sulphate Trihydrate, Mohammad Imtiazul Haque, Mohammad Umar
Turkish Journal of Physics
We report result obtained from an EPR study of vanadyl ion (VO^{2+}) in a single crystal of ferroelectric guanidinium uranyl sulphate trihydrate. The Spin-Hamiltonian parameters were also determined via EPR data. VO^{2+} enters the lattice interstitially at two distinguishable sites and resulting vanadyl complexes have nearly axial symmetry.
Influence Of The Nitrogen Concentration On The Electrical Characteristic Of Hydrogenated Amorphous Silicon Nitride (A-Sin_X:H) Based Schottky Diodes, İlker Ay, Hüseyi̇n Tolunay
Turkish Journal of Physics
In this study, the Schottky diode characteristic of hydrogenated amorphous silicon nitride (a-SiN_x:H) samples containing various amounts of nitrogen have been investigated via both I-V and C-V measurements. From forward bias I-V measurements in the dark, the barrier height of samples (\phi_{B0}), ideality factor (\eta ), modified Richardson constant (A^\ast) and series resistances (R_s) have been obtained as the function of temperature for different nitrogen content. In addition, forward and reverse bias current ratios (I_f/I_r) at V~=~1 volt have been investigated as the function of temperature for different nitrogen content. Light sensitivity of the samples has also been investigated under …
