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Iowa Recreational Property Ownership: Identification, Contact And Social Dynamics Of Multiple-Use Perennial Landcover, Mimi M. Wagner, James LaGro 2010 Iowa State University

Iowa Recreational Property Ownership: Identification, Contact And Social Dynamics Of Multiple-Use Perennial Landcover, Mimi M. Wagner, James Lagro

Leopold Center Completed Grant Reports

This research explored the opportunities for expanding the productive use of perennial landscapes in Iowa through expanded beef and dairy grazing owned recreational lands.


Integrated Soil And Weed Management Production Systems For Perennial Food Crops, Gail R. Nonnecke, Craig A. Dilley, Thomas E. Loynachan 2010 Iowa State University

Integrated Soil And Weed Management Production Systems For Perennial Food Crops, Gail R. Nonnecke, Craig A. Dilley, Thomas E. Loynachan

Leopold Center Completed Grant Reports

Several alternative weed management tactics for strawberry and grape production were tested for their effects on weed control, crop yield and soil quality enhancement.


Virtual Reality For Assembly Methods Prototyping: A Review, Abbishek Seth, Judy M. Vance, James H. Oliver 2010 Caterpillar, Inc.

Virtual Reality For Assembly Methods Prototyping: A Review, Abbishek Seth, Judy M. Vance, James H. Oliver

Mechanical Engineering Publications

Assembly planning and evaluation is an important component of the product design process in which details about how parts of a new product will be put together are formalized. A well designed assembly process should take into account various factors such as optimum assembly time and sequence, tooling and fixture requirements, ergonomics, operator safety, and accessibility, among others. Existing computer-based tools to support virtual assembly either concentrate solely on representation of the geometry of parts and fixtures and evaluation of clearances and tolerances or use simulated human mannequins to approximate human interaction in the assembly process. Virtual reality technology has ...


Assessing The Welfare Effects Of Us Biofuel Policies, Giancarlo Moschini, Harvey Lapan, Jingbo Cui, Joseph Cooper 2010 Iowa State University

Assessing The Welfare Effects Of Us Biofuel Policies, Giancarlo Moschini, Harvey Lapan, Jingbo Cui, Joseph Cooper

Economics Publications

This article assesses the main welfare implications of US policies to support biofuels, with an emphasis on corn-based ethanol. The analysis relies on an open economy, multimarket equilibrium model that links world and domestic energy and agricultural markets and explicitly accounts for the externalities of carbon emissions. The first-best policy in our context entails a carbon tax (implemented with a tax on fuel and a subsidy for ethanol), an import tariff on oil, and an export tax on corn. Although this policy is likely not feasible, we show that a second- best policy with an optimally chosen fuel tax and ...


Low-Temperature Adsorption Of H2s On Ag(111), Selena M. Russell, Da-Jiang Liu, Maki Kawai, Yousoo Kim, Patricia A. Thiel 2010 Iowa State University

Low-Temperature Adsorption Of H2s On Ag(111), Selena M. Russell, Da-Jiang Liu, Maki Kawai, Yousoo Kim, Patricia A. Thiel

Chemistry Publications

H2S forms a rich variety of structures on Ag(111) at low temperature and submonolayer coverage. The molecules decorate step edges, exist as isolated entities on terraces, and aggregate into clusters and islands, under various conditions. One type of island exhibits a (×)R25.3° unit cell. Typically, molecules in the clusters and islands are separated by about 0.4 nm, the same as the S–S separation in crystalline H2S. Density functional theory indicates that hydrogen-bonded clusters contain two types of molecules. One is very similar to an isolated adsorbed H2S molecule, with both ...


Formation And Coarsening Of Ag(110) Bilayer Islands On Nial(110): Stm Analysis And Atomistic Lattice-Gas Modeling, Yong Han, Barış Ünal, Dapeng Jing, Feili Qin, Cynthia J. Jenks, Da-Jiang Liu, Patricia A. Thiel, James W. Evans 2010 Iowa State University

Formation And Coarsening Of Ag(110) Bilayer Islands On Nial(110): Stm Analysis And Atomistic Lattice-Gas Modeling, Yong Han, Barış Ünal, Dapeng Jing, Feili Qin, Cynthia J. Jenks, Da-Jiang Liu, Patricia A. Thiel, James W. Evans

Chemistry Publications

Scanning tunneling microscopy analysis of the initial stages of film growth during deposition of Ag on NiAl(110) reveals facile formation of bilayer Ag(110) islands at temperatures of 130 K and above. Annealing subsequent to deposition at 130 K induces coarsening of the bilayer island distribution. The thermodynamic driving force for bilayer island formation reflects a lower relative surface energy for films of even layer thicknesses. This feature derives from quantum size effects due to electron confinement in the Ag film. The kinetics of island formation and relaxation is controlled by terrace and edge-diffusion barriers, detachment barriers, interlayer diffusion ...


Highly Active Heterogeneous Palladium Nanoparticle Catalysts For Homogeneous Electrophilic Reactions In Solution And The Utilization Of A Continuous Flow Reactor, Wenyu Huang, Jack Liu, Pinar Alayoglu, Yimin Li, Cole Whitman, Chia-Kuang Tsung, F. Dean Toste, Gabor Somorjai 2010 University of California - Berkeley

Highly Active Heterogeneous Palladium Nanoparticle Catalysts For Homogeneous Electrophilic Reactions In Solution And The Utilization Of A Continuous Flow Reactor, Wenyu Huang, Jack Liu, Pinar Alayoglu, Yimin Li, Cole Whitman, Chia-Kuang Tsung, F. Dean Toste, Gabor Somorjai

Wenyu Huang

highly active heterogeneous Pd-nanoparticle catalyst for the intramolecular addition of phenols to alkynes was developed and employed in a continuous flow reaction system. Running the reaction in flow mode revealed reaction kinetics, such as the activation energy and catalyst deactivation, and provides many potential practical advantages.


Seedless Polyol Synthesis And Co Oxidation Activity Of Monodisperse (111)- And (100)-Oriented Rhodium Nanocrystals In Sub-10 Nm Sizes, Yawen Zhang, Michael Grass, Wenyu Huang, Gabor Somoraji 2010 University of California - Berkeley

Seedless Polyol Synthesis And Co Oxidation Activity Of Monodisperse (111)- And (100)-Oriented Rhodium Nanocrystals In Sub-10 Nm Sizes, Yawen Zhang, Michael Grass, Wenyu Huang, Gabor Somoraji

Wenyu Huang

Monodisperse sub-10 nm (6.5 nm) sized Rh nanocrystals with (111) and (100) surface structures were synthesized by a seedless polyol reduction in ethylene glycol, with poly(vinylpyrrolidone) as a capping ligand. When using [Rh(Ac)2]2 as the metal precursor, (111)-oriented Rh nanopolyhedra containing 76% (111)-twinned hexagons (in 2D projection) were obtained; whereas, when employing RhCl3 as the metal precursor in the presence of alkylammonium bromide, such as tetramethylammonium bromide and trimethyl(tetradecyl)ammonium bromide, (100)-oriented Rh nanocubes were obtained with 85% selectivity. The {100} faces of the Rh nanocrystals are stabilized by chemically adsorbed ...


A Novel Subspace Outlier Detection Approach In High Dimensional Data Sets, Jinsong Leng 2010 Edith Cowan University

A Novel Subspace Outlier Detection Approach In High Dimensional Data Sets, Jinsong Leng

ECU Publications Pre. 2011

Many real applications are required to detect outliers in high dimensional data sets. The major difficulty of mining outliers lies on the fact that outliers are often embedded in subspaces. No efficient methods are available in general for subspace-based outlier detection. Most existing subspacebased outlier detection methods identify outliers by searching for abnormal sparse density units in subspaces. In this paper, we present a novel approach for finding outliers in the ‘interesting’ subspaces. The interesting subspaces are strongly correlated with `good' clusters. This approach aims to group the meaningful subspaces and then identify outliers in the projected subspaces. In doing ...


Aqueous Solvation Of Bihalide Anions, Daniel David Kemp, Mark S. Gordon 2010 Iowa State University

Aqueous Solvation Of Bihalide Anions, Daniel David Kemp, Mark S. Gordon

Chemistry Publications

Second-order Møller−Plesset perturbation theory (MP2) is used to perform geometry optimizations on XHX−·(H2O)n for X = Br, I, with n = 1 to 6 water molecules. Of particular interest is the manner in which the solvent molecules orient themselves around the solute and which configurations are lowest in energy. Although for most values of n, water molecules may donate all of their hydrogen atoms for hydrogen bonding to the solute, this type of structure is the lowest in energy only for n = 0 to 2 and is only a local minimum for n = 3, 4, and 6. For n ...


Book Review Of Quantum Chemistry, 2nd Edition, Thomas Holme 2010 Iowa State University

Book Review Of Quantum Chemistry, 2nd Edition, Thomas Holme

Chemistry Publications

This article presents a review of the second edition of Quantum Chemistry by D.A. McQuarrie.


Hygroscopic Growth And Deliquescence Of Nacl Nanoparticles Mixed With Surfactant Sds, Christopher W. Harmon, Ronald L. Grimm, Theresa M. McIntire, Mark D. Peterson, Bosiljka Njegic, Vanessa M. Angel, Ahmad Alshawa, Joelle S. Underwood, Douglas J. Tobias, R. Benny Gerber, Mark S. Gordon, John C. Hemminger, Sergey A. Nizkorodov 2010 University of California - Irvine

Hygroscopic Growth And Deliquescence Of Nacl Nanoparticles Mixed With Surfactant Sds, Christopher W. Harmon, Ronald L. Grimm, Theresa M. Mcintire, Mark D. Peterson, Bosiljka Njegic, Vanessa M. Angel, Ahmad Alshawa, Joelle S. Underwood, Douglas J. Tobias, R. Benny Gerber, Mark S. Gordon, John C. Hemminger, Sergey A. Nizkorodov

Chemistry Publications

Several complementary experimental and theoretical methodologies were used to explore water uptake on sodium chloride (NaCl) particles containing varying amounts of sodium dodecyl sulfate (SDS) to elucidate the interaction of water with well-defined, environmentally relevant surfaces. Experiments probed the hygroscopic growth of mixed SDS/NaCl nanoparticles that were generated by electrospraying aqueous 2 g/L solutions containing SDS and NaCl with relative NaCl/SDS weight fractions of 0, 5, 11, 23, or 50 wt/wt %. Particles with mobility-equivalent diameters of 14.0(±0.2) nm were size selected and their hygroscopic growth was monitored by a tandem nano-differential mobility analyzer ...


Controlling Magnetism Of A Complex Metallic System Using Atomic Individualism, Yaroslav Mudryk, Durga Paudyal, Vitalij K. Pecharsky, Karl A. Gschneidner Jr., Sumohan Misra, Gordon J. Miller 2010 Iowa State University

Controlling Magnetism Of A Complex Metallic System Using Atomic Individualism, Yaroslav Mudryk, Durga Paudyal, Vitalij K. Pecharsky, Karl A. Gschneidner Jr., Sumohan Misra, Gordon J. Miller

Chemistry Publications

When the complexity of a metallic compound reaches a certain level, a specific location in the structure may be critically responsible for a given fundamental property of a material while other locations may not play as much of a role in determining such a property. The first-principles theory has pinpointed a critical location in the framework of a complex intermetallic compound—Gd5Ge4—that resulted in a controlled alteration of the magnetism of this compound using precise chemical tools.


Euagxal11−X With The Bahg11-Type Structure: Composition, Coloring, And Competition With The Bacd11-Type Structure, Fei Wang, Karen N. Pearson, Warren E. Straszheim, Gordon J. Miller 2010 Iowa State University

Euagxal11−X With The Bahg11-Type Structure: Composition, Coloring, And Competition With The Bacd11-Type Structure, Fei Wang, Karen N. Pearson, Warren E. Straszheim, Gordon J. Miller

Chemistry Publications

EuAgxAl11−x phases adopting the BaHg11-type structure (space group Pmm, Z = 3) were synthesized with high yield by arc melting a mixture loaded as “EuAg3.5Al7.5” and annealing at 500 °C for 40 days. This phase has a very narrow phase width around EuAg4.0Al7.0; and it is unstable at 600 and 700 °C, at which it transforms into other phases. Magnetometry indicates that Eu is divalent, which gives the valence electron concentration per Ag/Al atom as 2.45 e/atom, higher than in ...


Structural And Magnetic Characteristics Of Gd5gaxsi4−X, Hui Wang, Sumohan Misra, Fei Wang, Gordon J. Miller 2010 Iowa State University

Structural And Magnetic Characteristics Of Gd5gaxsi4−X, Hui Wang, Sumohan Misra, Fei Wang, Gordon J. Miller

Chemistry Publications

A crystallographic study and theoretical analysis of the Si/Ga site preferences in the Gd5GaxSi4−x series is presented. Gd5GaxSi4−x adopt the orthorhombic Gd5Si4-type structure (space group Pnma, Z = 4) with a maximum Ga content near x = 1.00, as determined by single crystal and powder X-ray diffraction. Refinements from single crystal X-ray diffraction studies of the three independent sites for Si/Ga atoms in the asymmetric unit (interslab T1, intraslab T2 and T3) reveal partial mixing of these elements, with a clear preference for ...


M3(Au,Ge)19 And M3.25(Au,Ge)18 (M = Ca, Yb): Distinctive Phase Separations Driven By Configurational Disorder In Cubic Ycd6-Type Derivatives, Qisheng Lin, John D. Corbett 2010 The Ames Laboratory

M3(Au,Ge)19 And M3.25(Au,Ge)18 (M = Ca, Yb): Distinctive Phase Separations Driven By Configurational Disorder In Cubic Ycd6-Type Derivatives, Qisheng Lin, John D. Corbett

Chemistry Publications

Exploratory syntheses in the M−Au−Ge (M = Ca, Yb) systems have led to the discovery of two cleanly separated non-stoichiometric phases M3Au∼14.4Ge∼4.6 (I) and M3.25Au∼12.7Ge∼5.3 (II). Single crystal X-ray studies reveal that both (space group Im3̅) feature body-centered-cubic packing of five-shell multiply endohedral clusters that resemble those in the parent YCd6 (= Y3Cd18) and are akin to approximate phases in other quasicrystal systems. However, differences resulting from various disorders in these are distinctive. The innermost cluster in the M3Au∼14.4Ge∼4.6 phase (I) remains a disordered tetrahedron, as ...


Singlet And Triplet Potential Surfaces For The O 2 + C 2 H 4 Reaction, Kyoyeon Park, Aaron C. West, Erica Raheja, Bernhard Sellner, Hans Lischka, Theresa Lynn Windus, William L. Hase 2010 Texas Tech University

Singlet And Triplet Potential Surfaces For The O 2 + C 2 H 4 Reaction, Kyoyeon Park, Aaron C. West, Erica Raheja, Bernhard Sellner, Hans Lischka, Theresa Lynn Windus, William L. Hase

Chemistry Publications

Electronic structure calculations at the CASSCF and UB3LYP levels of theory with the aug-cc-pVDZ basis set were used to characterize structures, vibrational frequencies, and energies for stationary points on the ground state triplet and singlet O2+C2H4potential energy surfaces (PESs). Spin-orbit couplings between the PESs were calculated using state averaged CASSCF wave functions. More accurate energies were obtained for the CASSCF structures with the MRMP2/aug-cc-pVDZ method. An important and necessary aspect of the calculations was the need to use different CASSCF active spaces for the different reaction paths on the investigated PESs. The CASSCF calculations focused on O2+C2H4 ...


Development Of An Icosahedral Quasicrystal And Two Approximants In The Ca-Au-Sn System: Syntheses And Structural Analyses, Qisheng Lin, John D. Corbett 2010 The Ames Laboratory

Development Of An Icosahedral Quasicrystal And Two Approximants In The Ca-Au-Sn System: Syntheses And Structural Analyses, Qisheng Lin, John D. Corbett

Chemistry Publications

The realm of Tsai-type (YCd6-type) quasicrystals (QCs) and their approximants (ACs) continues to expand to the east in the periodic table. The heavy tetrel Sn is now one of the major components in the new Ca15.0(5)Au60.0(4)Sn25.0(2) (atom %) icosahedral QC and in the corresponding 1/1 and 2/1 ACs. (The 2/1 AC with Yb is also established.) Single-crystal X-ray diffraction on a 1/1 AC gives the refined formula of Ca3Au14.36(3)Sn4.38(5) in space group Im3̅, a = 15.131(1) Å, whereas a representative 2/1 ...


Multiple Nonstoichiometric Phases With Discrete Composition Ranges In The Caau5-Caau4bi-Biau2 System. A Case Study Of The Chemistry Of Spinodal Decomposition, Qisheng Lin, John D. Corbett 2010 The Ames Laboratory

Multiple Nonstoichiometric Phases With Discrete Composition Ranges In The Caau5-Caau4bi-Biau2 System. A Case Study Of The Chemistry Of Spinodal Decomposition, Qisheng Lin, John D. Corbett

Chemistry Publications

Synthetic explorations in the CaAu5−CaAu4Bi−BiAu2 system at 400 °C reveal five separate solid solution regions that show three distinct substitution patterns in the CaAu5 parent: (I) CaAu4(Au1−mBim) with 0 ≤ m ≤ 0.15(1), (II) 0.33(1) ≤ m ≤ 0.64(1), (III) 0.85(4) ≤ m ≤ 0.90(2); (IV) (Ca1−rAur)Au4(Bi1−sAus) with 0 ≤ r ≤ 0.39(1) and 0 ≤ s ≤ 0.12(2); (V) (Ca1−pqAupBiq)Au4Bi with 0.09(2) ≤ p ≤ 0.13(1) and 0.31(2) ≤ q ≤ 0 ...


Mesoporous Silica Nanoparticles: Structural Design And Applications, Igor I. Slowing, Juan Luis Vivero-escoto, Brian G. Trewyn, Victor S.Y. Lin 2010 Iowa State University

Mesoporous Silica Nanoparticles: Structural Design And Applications, Igor I. Slowing, Juan Luis Vivero-Escoto, Brian G. Trewyn, Victor S.Y. Lin

Chemistry Publications

The structural properties of mesoporous silica nanoparticles are reviewed. Different strategies for the introduction of functional groups are considered. Based on the architectural features of the material, the functionalization at defined regions of the particles is described, along with the properties emerging from the corresponding site-specific modifications of their chemistry. Many applications derived from the unique architecture and chemistry of these nanostructured composite materials are shown.


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