Chemistry Commons^™

11,12-Bis(2,2-Dimethyl­Prop­Yl)-9,10-Dihydro-9,10-Ethenoanthracene, Joseph P. Herres, Mark A. Forman, Kraig A. Wheeler

Kraig A. Wheeler

The title compound, C26H32, was retrieved as one of three products from the reaction of tert-butyl­lithium with 11,12-dimethyl­ene-9,10-dihydro­ethenoanthracene and 4,5-diiodo­penta­cyclo­[4.3.0.02,4.03,8.05,7]nonane. The structure shows the expected ethenoanthracene geometry with mol­ecules arranged via van der Waals surfaces.

54th Spsj Annual Meeting Yokohama, Japan, May 25-27, 2005, Jane C. Vogl, Hiroyuki Ohno

Otto Vogl

No abstract provided.

1,4-Dimethyl-1,4-Diazoniabicyclo[2.2.2]Octane Diiodide Acetonitrile Solvate, Daron E. Janzen, Paul C. Ewbank, Kent R. Mann

Daron E Janzen, Ph.D.

No abstract provided.

Macromolecules In Graz, Austria, December 3, 2004, Otto Vogl, Volker Ribitsch

Otto Vogl

No abstract provided.

Application Of Correlation-Gas Chromatography To Evaluate The Vaporization Enthalpy Of A Component In An Equilibrium Mixture, Manuel Temprado, James S. Chickos

James Chickos

No abstract provided.

Synthesis And Characterization Of Highly Amine Functionalized Mesoporous Organosilicas By An “All-In-One” Approach, Rebecca Voss, Arne Thomas, Markus Antonietti, Geoffrey A. Ozin

Rebecca Cademartiri

Mesoporous organosilicas (MOs) represent a promising class of organic–inorganic nanocomposites for a broad range of applications like catalysis, sensing, separation, or microelectronics. Their distinct feature is the presence of organic groups incorporated into the channel walls of a mesoporous structure. Here, we present a convenient “all-in-one” approach using silsesquioxane surfactant precursors for the functionalization of the channel walls with primary amine groups. The monomer is made by a hydroboration/aminolysis sequence on the base of a commercial monomer, with the template bound to the functionalization site by hydroboration and released after silica condensation and aminolysis. This combination ensures both the placement …

Polymers With Pendant Coumarins: Synthesis And Characterization Of Polystyrenes And Polymethacrylates With Pendant Coumarin Moieties, T. Christopher Corkery

Chris Corkery

No abstract provided.

An Entry To A Chiral Dihydropyrazole Scaffold:  Enantioselective [3 + 2] Cycloaddition Of Nitrile Imines, Mukund P. Sibi, Levi M. Stanley, Craig P. Jasperse

Levi M. Stanley

We have developed a versatile strategy to access dihydropyrazoles in highly enantioenriched form. Dipolar cycloaddition of electron-deficient acceptors and in situ-generated nitrile imines proceeds with high regio- and enantioselectivity using 10 mol % chiral Lewis acid catalyst. A variety of dihydropyrazoles that incorporate functionality for further manipulation have been prepared.

Chemical Manipulation Of High-Tc Ferromagnetism In Zno Diluted Magnetic Semiconductors, Kevin R. Kittilstved, D. R. Gamelin, N. S. Norberg

Kevin R. Kittilstved

We report the use of targeted p- and n-type chemical perturbations to manipulate high-TC ferromagnetism in Mn2+∶ZnO and Co2+∶ZnO in predictable and reproducible ways. We demonstrate a clear correlation between nitrogen and high-TC ferromagnetism for Mn2+∶ZnO and an inverse correlation for Co2+∶ZnO, both as predicted by recent theoretical models. These chemical perturbations reveal rich possibilities for exerting external control over high-TC spin ordering in diluted magnetic semiconductors.

11-(2,2-Dimethylpropyl)-12-{2-[12-(2,2-Dimethylpropyl)- 9,10-Dihydro-9,10-Ethenoanthracen-11-Yl]- Ethyl}-9,10-Dihydro-9,10-Ethenoanthracene, Joseph P. Herres, Mark A. Forman, Kraig A. Wheeler, Glenn P.A. Yap

Kraig A. Wheeler

Reaction of tert-butyllithium with 11,12-dimethylene-9,10- dihydro-9,10-ethanoanthracene and 4,5-diiodopentacyclo- [4.3.0.02,4.03,8.05,7]nonane gives three products, one of which crystallizes from petroleum ether as the title compound, C44H46, (I). Molecules of (I) are positioned on inversion centers (Z0 = 0.5) in the space group P21/n and lack any discernible intermolecular interactions.

Site-Specific And Synergistic Stimulation Of Methylation On The Bacterial Chemotaxis Receptor Tsr By Serine And Chew, Robert Weis

Robert Weis

Background Specific glutamates in the methyl-accepting chemotaxis proteins (MCPs) of Escherichia coli are modified during sensory adaptation. Attractants that bind to MCPs are known to increase the rate of receptor modification, as with serine and the serine receptor (Tsr), which contributes to an increase in the steady-state (adapted) methylation level. However, MCPs form ternary complexes with two cytoplasmic signaling proteins, the kinase (CheA) and an adaptor protein (CheW), but their influences on receptor methylation are unknown. Here, the influence of CheW on the rate of Tsr methylation has been studied to identify contributions to the process of adaptation. Results Methyl …

Size-Driven Domain Reorientation In Hydrothermally Derived Lead Titanate Nanoparticles, Zhiyuan Ye, Elliot B. Slamovich, Alexander H. King

Alexander H. King

High-resolution transmission electron microscopy studies of hydrothermally derived platelike lead titanate nanoparticles reveal that below a critical size of approximately 70 nm, the single ferroelectric domain polarization axis reorients from perpendicular to parallel to the plate. We suggest that during particle growth, ions in the hydrothermal processing medium compensate for the ferroelectric depolarization energy. When the processing medium is removed by washing and drying, single domain nanoparticles minimize their depolarization energy by c-axis flipping.

Amyloid-Β Protofibrils Differ From Amyloid-Β Aggregates Induced In Dilute Hexafluoroisopropanol In Stability And Morphology, Michael Nichols, Melissa A. Moss, Dana K. Reed, Stephanie Cratic-Mcdaniel, Jan H. Hoh, Terrone L. Rosenberry

Michael Nichols

Measurement Of The Vaporization Enthalpy Of Complex Mixtures By Correlation-Gas Chromatography. The Vaporization Enthalpy Of Rp-1, Jp-7, And Jp-8 Rocket And Jet Fuels At T = 298.15 K, James S. Chickos, Hui Zhao

James Chickos

No abstract provided.

Cubane, Cuneane, And Their Carboxylates: A Calorimetric, Crystallographic, Calculational, And Conceptual Coinvestigation., Maria Victoria Roux, Juan Z. Davalos, Pilar Jimenez, Rafael Notario, Obis Castano, James S. Chickos, William Hanshaw, Hui Zhao, Nigam Rath, Joel F. Liebman, Behzad S. Farivar, A. Bashir-Hashemi

James Chickos

No abstract provided.

The Thermochemistry Of 2,4-Pentanedione Revisited: Observance Of A Nonzero Enthalpy Of Mixing Between Tautomers And Its Effects On Enthalpies Of Formation, Manuel Temprado, Maria Victoria Roux, Patamaporn Umnahanant, Hui Zhao, James S. Chickos

James Chickos

No abstract provided.

Mathematical Modeling Of The Hypothalamic-Pituitary-Adrenal System Activity, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.

Involvement Of Porin N,N-Dicyclohexylcarbodiimide-Reactive Domain In Hexokinase Binding To The Outer Mitochondrial Membrane, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

Modeling And Analysis Of An On Line Fms, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

Novel Technique To Control The Premature Infant Incubator System Using Ann, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

Rules Of Ownership Of Artificial Persons Of Intellectual Property Rights -Comparative Study Between Jordanian, & French Laws-, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

The Role Of Knowledge Management In Enhancing The Competitiveness Of Small And Medium-Sized Enterprises (Smes), Philadelphia University

Philadelphia University, Jordan

No abstract provided.

Solar Cooker Utilizing Satellite Dish Technology, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

Evaluation Technique In The Spi-Calculus For Cryptographic Protocols, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

The State Of Engineering Postgraduate Studies In Iraqi Universities, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

An Approach Of Web Services Quality Attributes Specification, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

Mechanism Of Structural Transformation In Bismuth Titanate, Sudhanshu Mallick, Keith J. Bowman, Alexander H. King

Alexander H. King

Sodium-doped bismuth titanate undergoes a transformation from Bi4Ti3O12 to Na0.5Bi4.5Ti4O15 on heating in air at temperatures exceeding 800 °C. This transformation proceeds through the intermediate Na0.5Bi8.5Ti7O27 structure which is an intergrowth phase of the two. High-resolution transmission electron microscopy was used to study this transformation. From the Moiré pattern that was obtained, the crystallographic orientation of the transformation front has been determined and a mechanism is proposed for this structural transformation.

Photothermal Reshaping Of Prismatic Au Nanoparticles In Periodic Monolayer Arrays By Femtosecond Laser Pulses, Wenyu Huang, Wei Qian, Mostafa A. El-Sayed

Wenyu Huang

Prismatic goldnanoparticles in the periodic monolayer arrays prepared with nanosphere lithography technique can be reshaped with femtosecond laser pulses at different powers and wavelengths. As the power density of 400 nm femtosecond laser increases, the prismatic particle tips begin to round and the overall particle shape changes from a prism to a sphere with a tripodal intermediate. The formation of the tip-rounded nanoprisms is probably due to the dewetting properties of gold on quartz surface and the low melting temperature at the tips. The formation of the tripodal nanoparticles is attributed to the inhomogeneous heating and lattice rearrangement of the …

The Optically Detected Coherent Lattice Oscillations In Silver And Gold Monolayer Periodic Nanoprism Arrays:  The Effect Of Interparticle Coupling, Wenyu Huang, Wei Qian, Mostafa A. El-Sayed

Wenyu Huang

Using femtosecond transient spectroscopy, we studied the optically detected laser-induced coherent phonon oscillation of monolayers of periodic arrays of prismatic-shaped silver and gold nanoparticles, assembled by using the technique of nanosphere lithography. In this method, the same size of polystyrene sphere and the same vacuum conditions are used. Under these circumstances, the gold nanoprisms formed are found to have sharper tips than the corresponding silver nanoprisms. For both gold and silver nanoparticles, the surface plasmon absorption maximum is found to depend linearly on size. The coherent lattice oscillation periods are also found to depend linearly on size. However, although the …

Dislocation-Indenter Interaction In Nanoindentation, M. Ravi Shankar, Alexander H. King, Srinivasan Chandrasekar

Alexander H. King

A formulation of dislocation-indenter interaction in two-dimensional, isotropic elasticity is presented. A significant dislocation-indenter interaction is predicted when dislocations are nucleated very close to the indenter. This interaction is expected to have an important influence on dislocation motion and multiplication. Upon nucleation close to the indenter, the dislocations are shown to modify the load, load distribution, and moment acting on the indenter. This effect is seen to vary with the indentation contact length. Further away from the indenter, the indenter-dislocation interaction is shown to be negligible.