Physical Sciences and Mathematics Commons^™

Temperature Dependence Of The Double Layer Capacitance For The Restricted Primitive Model Of An Electrolyte Solution From A Density Functional Approach, Douglas Henderson, J. Reszko-Zygmunt, Stefan Sokolowski, Dezso Boda

Faculty Publications

We apply a different version of the density functional theory, given by Pizio, Patrykiejew, and Sokolowski [J. Chem. Phys. 121, 11957 (2004)], for a nonuniform restricted primitive model of an electrolyte solution to evaluate the temperature dependence of the capacitance of an electric double layer. We show that this theory is capable of reproducing the computer simulation data at a quantitative level. In particular, the reversal of the temperature dependence of the capacitance at low temperatures is predicted. This phenomenon has been difficult to predict from theory. Further, this theory also leads to an accurate description of the double layer …

Preparation Of 2s,3s-N-Isobutyl-N-(2-Hydroxy-3-Amino-4-Phenylbutyl)-P-Nitrobenzenesulfonylamide Hydrochloride And Other Derivatives Of 2-Hydroxy-1,3-Diamines, Aslam A. Malik, Hasan Palandoken, Joy A. Stringer, Roland P. Carlson, John Leach, Thomas G. Archibald, Robert G. Miotke

Chemistry and Biochemistry

The present invention provides a new process for the preparation of 2S,3S-N-isobutyl-N-(2-hydroxy-3-amino-4phenylbutyl)- p-nitrobenzenesulfonylamide hydrochloride, wherein this compound is prepared directly from the chloromethylalcohol. Importantly, the process of the present invention results in higher yields of 2S,3S-N-isobutyl-N-(2hydroxy -3 -amino -4-phenylbutyl) -pnitrobenzenesulfonylamide hydrochloride without sacrificing its purity. The processes of the present invention can be used to prepare not only the 2S,3S-derivative, but also the 2R,3S-, 2S,2R- and the 2R,3R-derivatives.

Method For Prevention Of Solid Dissolution Through Covalent Ligand Bonding, David A. Atwood

Chemistry Faculty Patents

Methods for preventing dissolution of solid substrates, such as metal leaching from coal or corrosion of metal surfaces, are provided.

To read the remainder of this abstract, please download this patent.

Developing A Genetic System For Functional Manipulations Of Fum1, A Polyketide Synthase Gene For The Biosynthesis Of Fumonisins In Fusarium Verticillioides, Fengan Yu, Xiangcheng Zhu, Liangcheng Du

Liangcheng Du Publications

Fumonisins are mycotoxins produced by Fusarium verticillioides, a filamentous fungus that is a widespread pathogen of corn. The biosynthesis of fumonisins is catalyzed by an iterative modular polyketide synthase (PKS). The study of the biosynthetic mechanism for these reduced fungal polyketides has been challenging due to the difficulties in detecting the intermediates with a linear carbon chain and manipulating the 7-domain PKS gene from the filamentous fungus. Here, we described the development of a genetic system for functionally manipulating the methyltransferase domain of FUM1 that is responsible for the assembly of a dimethylated 18-carbon chain. Using a two-stage screening strategy, …

Cystic Renal Neoplasia Following Conditional Inactivation Of Apc In Mouse Renal Tubular Epithelium, Chao Nan Qian, Jared Knol, Peter Igarashi, Fangming Lin

University Faculty Publications and Creative Works

Alterations in Wnt/β-catenin signaling have been linked to abnormal kidney development and tumorigenesis. To gain more insights into the effects of these alterations, we created mice carrying a conditional deletion of the Apc tumor suppressor gene specifically in the renal epithelium. As expected, the loss of Apc leads to increased levels of β-catenin protein in renal epithelium. Most of these mice die shortly after birth, and multiple kidney cysts were found upon histological examination. Only rarely did these animals survive to adulthood. Analysis of these adults revealed severely cystic kidneys associated with the presence of renal adenomas. Our results confirm …

Atomic Force Microscopy Investigation Of Virus Aggregation And Assembly At Chemical Templates Formed By Scanned Probe Nanolithography, Chin Li Cheung, S. -W. Chung, J. J. De Yoreo, A. Chatterji, T. Lin, J. E. Johnson

Barry Chin Li Cheung Publications

Aggregation and assembly of macromolecules are important processes in a number of scientific fields including structural biology, medicine, and materials science. For example, growth of well-ordered two-dimensional (2-D) arrays and bulk crystals remains the rate-limiting step in macromolecular structure determination. Uncontrolled aggregation of proteins is the source of a number of devastating pathologies such as Creutzfeldt-Jakob syndrome. Moreover, the demonstrated ability of engineered viruses and proteins to act as templates for growth of inorganic nanostructures is driving a need for methods to deterministically pattern their assembly at surfaces in order to fabricate hierarchical materials and devices.

Synthesis Of Relatively Highly Magnetic Nano-Sized Nizn-Ferrite In Microemulsion At 45 Oc, Vuk Uskoković, Miha Drofenik

Pharmacy Faculty Articles and Research

The procedure for the preparation of NiZn-ferrite powder with average particle size of 10 nm and saturation magnetization of 50 emu/g by using precipitation reaction between acidified sulphate precursor salts and NH4OH as the precipitating agent in the water-in-oil domain of the microemulsion CTAB/1-hexanol/water at 45 oC is presented herein. TEM measurements have revealed relatively uniform morphology of the particles, which are associated in coral-like agglomerates. EDS measurements have been used for qualitative analysis of the sample, whereby FAAS measurement has been performed in order to reveal the proportion of the cations in the sample - Ni : Zn : …

Hydroxy Double Salt Anion Exchange Kinetics: Effects Of Precursor Structure And Anion Size, Everson Kandare, Jeanne Hossenlopp

Chemistry Faculty Research and Publications

H NMR spectroscopy and powder X-ray diffraction have been used to explore the details of anion exchange reactions of two layered hydroxy double salts (HDSs), zinc copper hydroxy acetate (ZCA), nickel zinc hydroxy acetate (NZA), and a related layered material, zinc hydroxy acetate (ZHA), at room temperature (21−22 °C). Reactions that followed Avrami−Erofe'ev kinetics with respect to temporal profiles for acetate release, ZCA with butyrate (k = 1.7 × 10^-3 s^-1), and octanoate (k = 0.79 × 10^-3 s^-1) anions, as well as ZHA with octanoate (k = 2.6 × 10 …

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix: Neutronic Evaluation Of Zro2-Mgo Inert Fuels, E. Fridman, S. Kolesnikov, E. Shwageraus, A. Galperin

Fuels Campaign (TRP)

This report presents the results of the Task 3, defined in working program as: evaluation of burnable poison designs. Adopting the basic design of a standard PWR and Pu loadings required for 18-month cycle (results of Task 2), this part of the program is aimed to estimate performance of each BP design and BP material to address challenges of Fertile-Free Fuel (FFF) Concept. Finally, an optimal BP design will be developed and an overall feasibility of FFF concept will be determined. Basically, the main challenge encountered in neutronic design for a FFF core is to develop reactivity control system which …

Basic Region Of Residues 228-231 Of Protein Kinase Ck1Α Is Involved In Its Interaction With Axin: Binding To Axin Does Not Affect The Kinase Activity, Pablo Sobrado, Ana Jedlicki, Victor H. Bustos, Catherine C. Allende, Jorge E. Allende

Chemistry Faculty Research & Creative Works

Protein kinase CK1, also known as casein kinase 1, participates in the phosphorylation of β-catenin, which regulates the functioning of the Wnt signaling cascade involved in embryogenesis and carcinogenesis. β-catenin phosphorylation occurs in a multiprotein complex assembled on the scaffold protein axin. The interaction of CK1α from Dani rerio with mouse-axin has been studied using a pull-down assay that uses fragments of axin fused to glutathione S transferase, which is bound to glutathione sepharose beads. The results indicate that the three lysines present in the basic region of residues 228-231 of CK1α are necessary for the binding of CK1 to …

Green Photoluminescence From Platinum(Ii) Complexes Bearing Silylacetylide Ligands, Fei Hua, Solen Kinayyigit, John R. Cable, Felix Castellano

Chemistry Faculty Publications

The synthesis, structural characterization, photoluminescence properties, and density functional theory analysis of three Pt(II) diimine complexes, Pt(dbbpy)(CdropCR)(2) [dbbpy = 4,4'-di(tert-butyl-2,2'-bipyridine; R = -SiMe3, -CdropC-SiMe3, or -t-Bu], are presented. The Pt(dbbpy)(CdropC-tBu)(2) complex serves as a carbon-based ligand structure for which the photophysical properties of the two silicon-bearing complexes are compared in dichloromethane. Pt(dbbpy)(CdropC-SiMe3)(2) and Pt(dbbpy)(CdropC-CdropC-SiMe3)(2) display visible absorptions with strong green emission (lambda(emmax) = 526 and 524 nm, respectively) while Pt(dbbpy)(CdropCt-Bu)(2) displays efficient, long-lived yellow emission (lambda(emmax) = 557 nm). Direct side by side comparisons of Pt(dbbpy)(CdropC-SiMe3)(2) and Pt(dbbpy)(CdropC-t-Bu)(2) suggest that the difference in excited state energy results from the relative …

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

Chemistry & Biochemistry Faculty Works

The brains of Alzheimer’s disease (AD) patients contain large numbers of amyloid plaques that are rich in fibrils composed of 40- and 42-residue amyloid-β (Aβ) peptides. Several lines of evidence indicate that fibrillar Aβ and especially soluble Aβ aggregates are important in the etiology of AD. Recent reports also stress that amyloid aggregates are polymorphic and that a single polypeptide can fold into multiple amyloid conformations. Here we demonstrate that Aβ-(1–40) can form soluble aggregates with predominant β-structures that differ in stability and morphology. One class of aggregates involved soluble Aβ protofibrils, prepared by vigorous overnight agitation of monomeric Aβ-(1–40) …

Studies Of The Relationship Between The Structure And Properties Of Interfacial Thin Films, Mark Anderson

Mark R. Anderson

No abstract is available at this time.

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

Planar-To-Tubular Structural Transition In Boron Clusters: B20 As The Embryo Of Single-Walled Boron Nanotubes, Boggavarapu Kiran, Satya S. Bulusu, Hua-Jin Zhai, Soohaeng Yoo, Xiao Cheng Zeng, Lai-Sheng Wang

Xiao Cheng Zeng Publications

Experimental and computational simulations revealed that boron clusters, which favor planar (2D) structures up to 18 atoms, prefer 3D structures beginning at 20 atoms. Using global optimization methods, we found that the B₂₀ neutral cluster has a double-ring tubular structure with a diameter of 5.2 Å. For the B₂₀^- anion, the tubular structure is shown to be isoenergetic to 2D structures, which were observed and confirmed by photoelectron spectroscopy. The 2D-to-3D structural transition observed at B₂₀, reminiscent of the ring-to-fullerene transition at C₂₀ in carbon clusters, suggests it may be considered as the embryo …

In Situ Anomalous Small-Angle X-Ray Scattering From Metal Particles In Supported-Metal Catalysts. Ii. Results, H. Brumberger, D. Hagrman, Jerry Goodisman, K. D. Finkelstein

Chemistry - All Scholarship

Information about the metal phase in a supported-metal catalyst can be obtained using anomalous small-angle X-ray scattering (ASAXS). The difference between the scattering profiles for SAXS at two different wavelengths near the metal's absorption edge is essentially the scattering of the metal alone. Novel in situ ASAXS measurements are made on mordenite impregnated with platinum metal while the temperature and composition of gas in the sample cell are changed. Measurements are made 62 times during treatment of the catalyst. The metal particles are assumed to be randomly distributed spheres with N(R)dR = number of spheres with radii between R and …

Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix: Quaterly Report October-December 2004, Spencer M. Steinberg

Separations Campaign (TRP)

We have conducted a large number of experiments to determine the possible reaction of iodate with sphagnum peat moss. These experiments indicate that the natural organic material reacts with iodate resulting in the formation of organically bound iodine and/or iodide in solution.

In the last quarter, we have conducted a number of experiments at various pHs and several temperatures (70oC, 60oC and 40oC). The reaction of iodate with peat follows pseudo first-order kinetics, although the reaction rate does appear to decrease significantly with reaction time. As noted in a previous report organically bound iodine appears to go through a maximum …

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.

Impact Of Alteration Phase Formation And Microbial Activity On The Fate And Transport Of The Actinides And Fission Products: Alteration Phase Analysis, James Cizdziel, Klaus J. Stetzenbach, Thomas Williams, Abe Van Luik

Publications (YM)

The study of the behavior and movement of radionuclides in the environment is significant to many projects of interest to Southern Nevada, especially for the proposed Yucca Mountain Repository, as well as to the nation-wide issues of radiological releases from a variety of scenarios. Understanding and predicting the release, transport, and fate of radionuclides, particularly the actinide elements, in the Mojave/Great Basin geology is an extremely challenging, multi-faceted problem. In support of the national program to deepen our understanding of the behavior of radionuclides in the environment and to better predict the performance of a geological repository at Yucca Mountain, …

Characterization Of Microbial Activity, Mark P. Buttner, Patricia Cruz, Klaus J. Stetzenbach, Abe Van Luik, Thomas Williams, Amy J. Smiecinski

Publications (YM)

The overall goal of this study is to investigate the phenomena that affect the fate and transport of radionuclides in the environment. The objective of this task, “Characterization of Microbial Activity”, is to develop a molecular biological method for the characterization of the microbial population indigenous to the Yucca Mountain Project site, with emphasis in detection and measurement of species or groups of microorganisms that could be involved in actinide and/or metal reduction, and subsurface transport. Subtasks consist of QA planning and preparation, and literature review. This task is part of a cooperative agreement between the UNLV Research Foundation and …

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.

Modifications Of Human Βa1/Βa3-Crystallins Include S-Methylation, Glutathiolation, And Truncation, Veniamin N. Lapko, Ronald Cerny, David L. Smith, Jean B. Smith

Ronald Cerny Publications

Disulfide bonding of lens crystallins contributes to the aggregation and insolubilization of these proteins that leads to cataract. A high concentration of reduced glutathione is believed to be key in preventing oxidation of crystallin sulfhydryls to form disulfide bonds. This protective role is decreased in aged lenses because of lower glutathione levels, especially in the nucleus. We recently found that human [1]-crystallins undergo S-methylation at exposed cysteine residues, a reaction that may prevent disulfide bonding. We report here that βA1/A3-crystallins are also methylated at specific cysteine residues and are the most heavily methylated of the human lens crystallins. Among the …

Reaction Rates For The Dehalogenation Of Trichloroethylene Using Various Types Of Zero-Valent Iron, Neil Stewart

Electronic Theses and Dissertations

Remediation of trichloroethylene (TCE) and other chlorinated solvents is of great concern due to their toxicity and their persistence in the environment. Iron has been used extensively in the past decade as a subsurface reactive agent for the remediation of dense, nonaqueous-phase liquids (DNAPLs). Permeable reactive barrier walls (PRBW) have been installed at many sites around the country to treat contaminated plumes resulting from the presence of DNAPL pools. The use of zero-valent metals, such as iron, to effectively reductively dechlorinate DNAPLs has been employed as the reactive material in these PRBWs (Gillham et al., 1993). However, limited work has …

Structural Study Of Disease Related Proteins, Ayse Sinem Ozyurt

Electronic Theses and Dissertations

The availability of complete sequences for the genomes of many organisms changes the researcher's attention from genome sequencing to finding the function of gene products, the proteins. The three dimensional (3D) structure of a protein is helpful to understand its function, because tertiary structure is more conserved in evolution than sequence. The 3D structures can be found quickly by using high-throughput (HT) methods for protein expression, purification, characterization and structure determination. This process is very challenging in every step. Therefore we selected nearly 200 cancer related proteins as targets to see the difficulties in trying to determine the web predicted …

A Solvent-Free Baeyer–Villiger Lactonization For The Undergraduate Organic Laboratory: Synthesis Of Γ-T-Butyl-Ε-Caprolactone, John J. Esteb, James N. Hohman, Diana E. Schladaminger, Anne M. Wilson

Scholarship and Professional Work - LAS

We present an experiment involving the Baeyer–Villiger oxidation reactionfor a first-year organic chemistry class. The Baeyer–Villiger reactionprovides an efficient method to convert ketones to esters or lactones. Most organictextbooks cover the Baeyer–Villiger reaction but owing to a lack of suitableexperiments, students seldom get to explore the reaction in the undergraduateteaching laboratory. In this experiment, m-chloroperoxybenzoic acid(m-CPBA) and4-tert-butylcyclohexanone are mixed together for 30 minutes under solvent-freeconditions to produce γ-t-butyl-ε-caprolactone in 95%yield. The solvent-free nature of this procedure greatly limits the quantityof waste generated by students and keeps costs low by removing the need for solvent.

Benzocycloheptynedicobalt Complexes By Intramolecular Nicholas Reactions, Y. Ding, James R. Green

Chemistry and Biochemistry Publications

Lewis acid mediated intramolecular Nicholas reactions of aryl (Z)-enyne propargyl acetate-CO2(CO)(6) complexes 1 afford benzocycloheptenyne-CO2(CO)(6) complexes 2 and their heterocyclic analogues.

Intramolecular Pauson-Khand Reactions Of Cycloheptynedicobalt Complexes, Ahmed B. Mohamed, James R. Green, Jason Masuda

Chemistry and Biochemistry Publications

Cycloheptyne-Co-2(CO)(6) complexes bearing alkenes tethered by oxygen, sulfur, and nitrogen atoms undergo Pauson-Khand reactions to afford tricyclic compounds containing a fused 7,5-ring system.

Removal Of P-Cresol Sulfate By Hemodialysis, Andres W. Martinez, Natalie S. Recht, Thomas H. Hostetter, Timothy W. Meyer

Chemistry and Biochemistry

Protein-bound solutes are poorly cleared by dialysis. Among the most extensively studied of these solutes is p-cresol, which has been shown to be toxic in vitro. This study examined the form in which p-cresol circulates and quantified its removal by hemodialysis. HPLC analysis of plasma from hemodialysis patients contained a peak whose mobility corresponded to synthetic p-cresol sulfate (PCS) but no detectable unconjugated p-cresol. Treatment with sulfatase resulted in recovery of this peak as p-cresol, confirming its identity. Subsequent studies compared the removal of PCS and another protein-bound solute, indican, to the removal of urea during clinical hemodialysis treatments. …

Thermodynamics Of Folding And Association Of Lattice-Model Proteins, Troy Cellmer, Dusan Bratko, John M. Prausnitz, Harvey Blanch

Chemistry Publications

Closely related to the “protein folding problem” is the issue of protein misfolding and aggregation. Proteinaggregation has been associated with the pathologies of nearly 20 human diseases and presents serious difficulties during the manufacture of pharmaceutical proteins. Computational studies of multiprotein systems have recently emerged as a powerful complement to experimental efforts aimed at understanding the mechanisms of proteinaggregation. We describe the thermodynamics of systems containing two lattice-model 64-mers. A parallel tempering algorithm abates problems associated with glassy systems and the weighted histogram analysis method improves statistical quality. The presence of a second chain has a substantial effect on single-chain …