Chemistry Commons^™

Quantum Trajectory Dynamics In Imaginary Time With The Momentum-Dependent Quantum Potential, Sophya Garashchuk

Faculty Publications

The quantum trajectory dynamics is extended to the wave function evolution in imaginary time. For a nodeless wave function a simple exponential form leads to the classical-like equations of motion of trajectories, representing the wave function, in the presence of the momentum-dependent quantum potential in addition to the external potential. For a Gaussian wave function this quantum potential is a time-dependent constant, generating zero quantum force yet contributing to the total energy. For anharmonic potentials the momentum-dependent quantum potential is cheaply estimated from the global Least-squares Fit to the trajectory momenta in the Taylor basis. Wave functions with nodes are …

Homozygous Frameshift Mutation In Tmco1 Causes A Syndrome With Craniofacial Dysmorphism, Skeletal Anomalies, And Mental Retardation, Baozhong Xin, Erik G. Puffenberger, Susan Turben, Haiyan Tan, Aimin Zhou, Heng Wang

Chemistry Faculty Publications

We identified an autosomal recessive condition in 11 individuals in the Old Order Amish of northeastern Ohio. The syndrome was characterized by distinctive craniofacial dysmorphism, skeletal anomalies, and mental retardation. The typical craniofacial dysmorphism included brachycephaly, highly arched bushy eyebrows, synophrys, long eyelashes, low-set ears, microdontism of primary teeth, and generalized gingival hyperplasia, whereas Sprengel deformity of scapula, fusion of spine, rib abnormities, pectus excavatum, and pes planus represented skeletal anomalies. The genome-wide homozygosity mapping using six affected individuals localized the disease gene to a 3.3-Mb region on chromosome 1q23.3-q24.1. Candidate gene sequencing identified a homozygous frameshift mutation, c.139_140delAG, in …

Annealing Temperature And Initial Iron Valence Ratio Effects On The Structural Characteristics Of Nanoscale Nickel Zinc Ferrite, S. Calvin, M. D. Schultz, L. Glowzenski, E. E. Carpenter

Chemistry Publications

Nickelzincferrite (NZFO) nanoparticles were synthesized via a reverse micelle method with a nonionic surfactant. Three different initial Fe3+/Fe2+ ratios were employed along with three different firing temperatures (200, 500, 1000 °C) to investigate the effects on the NZFO system. Extended x-rayabsorption fine structure (EXAFS) results reveal zinc loss at high annealing temperatures; at 1000 °C, the loss is nearly total for Fe3+/Fe2+ ratios other than 10:90. Annealing at 500 °C, however, appears necessary for fully incorporating the zinc and nickel into the spinel phase. The best nanoferrite was thus obtained using an initial Fe3+/Fe2+ ratio of 10:90 and a moderate …

Dual Mode Nanoparticles: Cds Coated Iron Nanoparticles, F. N. Radwan, K. J. Carroll, E. E. Carpenter

Chemistry Publications

Reverse micelles can be used in a sequential fashion to make core-shell nanoparticles. Using this technique it is possible to make a magnetic quantum dot, by coating an iron core with a cadmium sulfide shell. Transmission electron microscopy indicated core-shell morphology and narrow size distribution of the obtained particles. Collectively, x-ray powder diffraction and x-ray photoelectron spectroscopy verified the presence of cadmium sulfide on the surface of the nanoparticles. Optical properties of the coated particles were demonstrated using fluorescence spectroscopy. A vibrating sample magnetometer was used to determine magnetic properties. Dual mode cadmium sulfide coatediron core-shell nanoparticles make unique candidates …

High Magnetization Aqueous Ferrofluid: A Simple One-Pot Synthesis, Kyler J. Carroll, Michael D. Schultz, Panos P. Fatouros, Everett E. Carpenter

Chemistry Publications

A one-step polyol method was utilized to prepare a stable aqueous iron/iron oxide ferrofluid. The dried powders were characterized by x-ray diffraction, electron microscopy, x-ray absorption spectroscopy, and vibrating sample magnetometry for the determination of phase, morphology, and magnetic properties. To show its potential for imaging applications, the ferrofluid was also investigated as a magnetic resonance imaging contrast agent.

Summary Of Work While A Link Energy Fellow, Michael T. Colvin

Link Foundation Energy Fellowship Reports

Electrons have an intrinsic property called spin, which is found in one of two states, an “up” and a “down”. The spin state of an electron can be observed and differentiated by applying an external magnetic field and inducing transitions with microwaves. The bulk of my graduate work has focused on understanding, controlling, and transferring spin information in molecular systems in the presence of light. If we can understand and transfer spin information it could be used for quantum computing which could revolutionize computing and information processing. This undertaking is difficult and at this point remains largely unexplored in organic …

Thiol-Ene Chemistry For The Synthesis And Modification Of Branched Organosilicon Polymers, David Son, Christiana Rissing, Li Chen, Theodore Andersson

Chemistry Research

No abstract provided.

2-(9-Anthrylmethyl­­Idene­Amino)-4-Methyl­Phenol, Ralph Isovitsch

Chemistry

The title compound, C22H17NO, is a novel Schiff base synthesized via a condensation reaction between 9-anthracenecarboxaldehyde and 2-amino-p-cresol. The asymmetric unit contains two independent mol­ecules that are joined by an O—H⋯OH hydrogen bond. An intra­molecular O—H⋯N hydrogen bond occurs in each mol­ecule. π-stacking about inversion centers was observed between adjacent phenol rings [centroid–centroid distance = 3.850 (2) Å] and adjacent anthracene rings [centroid–centroid distance = 3.834 (2) Å]. The C—N=C—C torsion angles between the phenol and anthracene rings are close to 180° with values of 174.06 (15) and 179.85 (14)°.

The Synthesis, Photophysical Characterization, And X‐Ray Structure Analysis Of Two Polymorphs Of 4,4′‐Diacetylstilbene, Ralph Isovitsch, Cameron Pye, Frank R. Fronczek

Chemistry

A palladium(II) acetate‐catalyzed synthesis of 1 that utilizes the novel triazene 1‐{4‐[(E)‐morpholin‐4‐yldiazenyl]phenyl}ethanone as a synthon is described. The room temperature absorption spectra of 1 in various solvents exhibited a π→π* transition in the range of 330–350 nm. Compound 1 was observed to be luminescent, with room‐temperature solution and solid‐state emission spectra that exhibited maxima in the range 400–500 nm. All room‐temperature absorption and emission spectra exhibited some degree of vibrational structure. The emission spectrum of 1 at 77 K in propanenitrile glass was broad and featureless with a maximum at 447 nm. Compound 1 crystallized …

Elucidation Of Fragmentation Pathways Of Nitrile-Terminated Ppi Dendrimer-Metal Complexes, Kristen Nicole Pack

Theses, Dissertations and Capstones

The complexity of branching macromolecules around a core unit, such as poly(propylene)imine (PPI) dendrimers, has caught the attention of researchers for several years^1,2,3,4,5. The structural framework of the core unit for these dendrimers is simply 1,4- diaminobutane. As the synthesis of higher-order generations of the macromolecule progresses, the molecules become very complex and tightly woven, but have predictable geometries and properties. The PPI dendrimers can be functionalized at the terminal ends of the branches in order to elicit different properties. The PPI dendrimer examined in this project has been terminated with a nitrile group rather than the usual …

Kinetic Analysis Of Prodrug Activation And Atp/Utp Substrate Preference Of Nine Human Deoxycytidine Kinase Mutants, Breanna Wentz, Jaclyn Einspahr, Michael H. Godsey

CUP Undergraduate Research

Deoxynucleoside analogues are prodrugs that canfunction as inhibitors of both viral and cellular DNA replication processes. They are important in anti-cancer therapy because they hinder DNA synthesis and cellular mitosis. Within the cell, deoxyribonucleotides are synthesized using the salvage pathways by converting the unphosphorylated nucleosides to their mono, di- and tri-phosphate forms using a phosphoryl donor: ATP or UTP. Human deoxycytidine kinase (dCK) is the first and rate-limiting enzyme in this process. The dCK protein uses nucleotide triphosphates to phosphorylate several clinically important nucleoside analogue prodrugs in addition to its natural substrates. The preferred physiological phosphoryl donor for dCK is …

2,3-Bis(Bromomethyl)-1,4-Diphenylbenzene, Jonathan B. Briggs, Mikael D. Jazdzyk, Glen P. Miller

Chemistry

In the title compound, C(20)H(16)Br(2), the terminal phenyl groups are twisted away from the central ring by approximately 55 and -125 degrees (average of four dihedral angles each), respectively. The crystal structure is stabilized by a combination of interMolecular and intraMolecular interactions including interMolecular pi-pi stacking interactions [C atoms of closest contact = 3.423 ( 5) angstrom].

Novel Photochemical Methodologies For Diversity Oriented Synthesis And Screening Of Combinatorial Libraries, Roman Askatovich Valiulin

Electronic Theses and Dissertations

The main goal of this project was to develop an efficient methodology allowing rapid access to structurally diverse scaffolds decorated with various functional groups.

Initially, we discovered and subsequently developed an experimentally straightforward, high-yielding photoinduced conversion of readily accessible diverse starting materials into polycyclic aldehydes and their (hemi)acetals decorated by various pendants. The two step sequence, involving the Diels-Alder addition of heterocyclic chalcones and other benzoyl ethylenes to a variety of dienes, followed by the Paternò-Büchi reaction, was described as an alkene-carbonyl oxametathesis. This methodology offers a rapid increase in molecular complexity and diversity of the target scaffolds.

To develop …

The Analysis Of Cyanide And Its Breakdown Products In Biological Samples, Brian A. Logue, Diane M. Hinkens, Steven I. Baskin, Gary A. Rockwood

Chemistry and Biochemistry Faculty Publications

Cyanide is a toxic chemical that may be introduced into living organisms as a result of natural processes and/or anthropogenic uses (legal or illicit). Exposure to cyanide can be verified by analysis of cyanide or one of its breakdown products from biological samples. This verification may be important for medical, law-enforcement, military, forensic, research, or veterinary purposes. This review will discuss current bioanalytical techniques used for the verification of cyanide exposure, identify common problems associated with the analysis of cyanide and its biological breakdown products, and briefly address the metabolism and toxicokinetics of cyanide and its breakdown products in biological …

Electrochemical Sensing In Paper-Based Microfluidic Devices, Zhihong Nie, Christian A. Nijhuis, Jinlong Gong, Xin Chen, Alexander Kumachev, Andres W. Martinez, Max Narovlyansky, George M. Whitesides

Chemistry and Biochemistry

This paper describes the fabrication and the performance of microfluidic paper-based electrochemical sensing devices (we call the microfluidic paper-based electrochemical devices, μPEDs). The μPEDs comprise paper-based microfluidic channels patterned by photolithography or wax printing, and electrodes screen-printed from conducting inks (e.g., carbon or Ag/AgCl). We demonstrated that the μPEDs are capable of quantifying the concentrations of various analytes (e.g., heavy-metal ions and glucose) in aqueous solutions. This low-cost analytical device should be useful for applications in public health, environmental monitoring, and the developing world.

Technology For The Organic Chemist: Three Exploratory Modules, John J. Esteb, Luanne M. Mcnulty, John Magers, Paul Morgan

Scholarship and Professional Work - LAS

The ability to use computer-based technology is an essential skill set for students majoring in chemistry. This exercise details the introduction of appropriate uses for this technology in the organic chemistry series. The incorporation of chemically appropriate online resources (module 1), scientific databases (module 2), and the use of a chemical drawing program (module 3) are detailed here.

A Bland–Altman Comparison Of The Lead Care® System And Inductively Coupled Plasma Mass Spectrometry For Detecting Low-Level Lead In Child Whole Blood Samples, Christina Sobin, Tanner Schaub, Natali Parisi, Eva De La Riva

Selected Works Temporary Series

Chronic childhood lead exposure, yielding blood lead levels consistently below 10 μg/dL, remains a major public health concern. Low neurotoxic effect thresholds have not yet been established. Progress requires accurate, efficient, and cost-effective methods for testing large numbers of children. The LeadCare® System (LCS) may provide one ready option. The comparability of this system to the “gold standard” method of inductively coupled plasma mass spectrometry (ICP-MS) for the purpose of detecting blood lead levels below 10 μg/dL has not yet been examined. Paired blood samples from 177 children ages 5.2–12.8 years were tested with LCS and ICP-MS. Triplicate repeat tests …

Physicochemical And Thermochemical Properties Of Sulfonated Poly(Etheretherketone) Electrolyte Membranes, Stephen Rhoden

Electronic Theses and Dissertations

Fuel cells have long been seen as an alternative to combustion powered and diesel powered engines and turbines. Production of energy via a fuel cell conversion method can generate up to 60% efficiency in comparison to 30% using a combustion powered engine, with low co-production of harmful side-products. The polymer electrolyte membrane (PEM) adapted for the fuel cell application is one of the main components that determines the overall efficiency. This research project was focused towards novel PEMs, such as sulfonated poly(etheretherketone) or SPEEK, which are cost-efficient and robust with high proton conductivities under hydrated conditions. The degree of sulfonation …

Structure-Reactivity Relationships Of L-Proline Derived Spirolactams And A-Methyl Prolinamide Organocatalysts In The Asymmetric Michael Addition Reaction Of Aldehydes To Nitroolefins., Fintan Kelleher, Sinead Kelly, John Watts, Vickie Mckee

Articles

L-Proline derived spirolactams and a-methyl prolinamides act as organocatalysts for the asymmetric conjugate addition of aldehydes to nitroolefins in excellent yields, with good diastereoselectivity and enantioselectivity. Furthermore, low catalyst loadings (5 mol%) and a low aldehyde molar excess (1.5 molar equivalents) were achieved.

Mechanistic Importance Of Redox Potentials And Conformational Flexibility In Electron-Transferring Flavoproteins, Michael Anthony Swanson

Electronic Theses and Dissertations

The mitochondrial matrix flavoproteins electron transfer flavoprotein (ETF) and electron transfer flavoprotein-ubiquinone oxidoreductase (ETF-QO) are responsible for linking fatty acid β-oxidation with the main mitochondrial respiratory chain. Electrons derived from flavoprotein dehydrogenases are transferred sequentially through ETF and ETF-QO to ubiquinone and then into the respiratory chain via complex III. In this study, the effects of changes in ETF-QO redox potentials on its activity and the conformational flexibility of ETF were investigated.

ETF-QO contains one [4Fe-4S]^2+,1+ and one flavin adenine dinucleotide (FAD). In the porcine protein, threonine 367 is hydrogen bonded to N1 and O2 of the flavin ring …

Mechanistic And Computational Studies Of Oxidatively-Induced Aryl-Cf3 Bond Formation At Palladium, J. Brannon Gary

Faculty Publications

This article describes the rational design of 1st generation systems for oxidatively-induced Aryl– CF3 bond-forming reductive elimination from PdII. Treatment of (dtbpy)PdII(Aryl)(CF3) (dtbpy = di-tert-butylbipyridine) with NFTPT (N-fluoro-1,3,5-trimethylpyridium triflate) afforded the isolable PdIV intermediate (dtbpy)PdIV(Aryl)(CF3)(F)(OTf). Thermolysis of this complex at 80 °C resulted in Aryl–CF3 bond-formation. Detailed experimental and computational mechanistic studies have been conducted to gain insights into the key reductive elimination step. Reductive elimination from this PdIV species proceeds via pre-equilibrium dissociation of TfO− followed by Aryl–CF3 coupling. DFT calculations reveal that the transition state for Aryl–CF3 bond formation involves the CF3 acting as an electrophile with the …

Platinum And Palladium Complexes Containing Cationic Ligands As Catalysts For Arene Hid Exchange And Oxidation., J. Brannon Gary

Faculty Publications

The direct functionalization of CH bonds has frequently been deemed a “Holy Grail” of organometallic chemistry.[1] A seminal example of this transformation was the demonstration by Shilov and co-workers that platinum(II) salts catalyze the direct oxidation of alkanes into their corresponding alcohols and alkyl halides.[2] Subsequent work in this area has focused on surveying diverse ligands for these reactions in an effort to enhance reactivity and selectivity, slow catalyst decomposition, and replace platinum(IV)-based oxidants with more cost-effective alternatives.[3–5] In a key development, chemists at Catalytica identified [bpymPtCl2] (bpym = bipyrimidine) as a pre-catalyst for the oxidation of CH4 into CH3OSO3H …

Towards The Total Synthesis Of Haplomyrtin, Nora Ellen Hunter

Browse all Theses and Dissertations

Haplomyrtin, a 1-aryl-2,3-naphthalide lignan obtained from Turkish Haplophyllum myrtifolium and Haplophyllum telephioides offers a number of synthetic challenges with the incorporation of two aromatic hydroxyl groups at positions C4 and C7 on the naphthalene ring system and regiospecific condensation of the γ-lactone ring. Improvements towards the total synthesis of haplomyrtin were pursued with commercially available vanillin and piperonal in a total of 8 separate steps. All steps have excellent reproducibility. This strategy includes bromination of protected vanillin to yield 2-(4-(4-methoxybenzyloxy)-2-bromo-5-methoxyphenyl)-1,3-dioxolane and 2-(4-(benzyloxy)-2-bromo-5-methoxyphenyl)-1, 3-dioxolane in 48% and 88% yield respectively, and incorporation of the fully functionalized pendant aryl ring through a …

10,12-Dimethylpteridino[6,7-F][1,10]- Phenanthroline-11,13(10h,12h)-Dione– Chloroform (1/1), Waynie Olaprath, Jennifer Rodin, Kraig A. Wheeler, Mark E. Mcguire

Faculty Research and Creative Activity

In the title co-crystal, C18H12N6O2_CHCl3, intramolecular Cl3C—H_ _ _N hydrogen-bonding interactions occur between a single CHCl3 and both N atoms at the 1,10-positions on the phenanthroline portion of the molecule. The interplanar distance between inversion-related molecules is 3.241 (2) A ° .

Programmable Diagnostic Devices Made From Paper And Tape, Andres W. Martinez, Scott T. Phillips, Zhihong Nie, Chao-Min Cheng, Emanuel Carrilho, Benjamin J. Wiley, George M. Whitesides

Chemistry and Biochemistry

This paper describes three-dimensional microfluidic paper-based analytical devices (3-D μPADs) that can be programmed (postfabrication) by the user to generate multiple patterns of flow through them. These devices are programmed by pressing single-use ‘on’ buttons, using a stylus or a ballpoint pen. Pressing a button closes a small space (gap) between two vertically aligned microfluidic channels, and allows fluids to wick from one channel to the other. These devices are simple to fabricate, and are made entirely out of paper and double-sided adhesive tape. Programmable devices expand the capabilities of μPADs and provide a simple method for controlling the movement …

Millimeter-Scale Contact Printing Of Aqueous Solutions Using A Stamp Made Out Of Paper And Tape, Chao-Min Cheng, Aaron D. Mazzeo, Jinlong Gong, Andres W. Martinez, Scott T. Phillips, Nina Jain, George M. Whitesides

Chemistry and Biochemistry

This communication describes a simple method for printing aqueous solutions with millimeter-scale patterns on a variety of substrates using an easily fabricated, paper-based microfluidic device (a paper-based ―stamp‖) as a contact printing device. The device is made from inexpensive materials, and it is easily assembled by hand; this method is thus accessible to a wide range of laboratories and budgets. A single device was used to print over 2500 spots in less than three minutes at a density of 16 spots per square centimetre. This method provides a new tool to pattern biochemicals—reagents, antigens, proteins, and DNA—on planar substrates. The …

What Is Wrong With Water Barometers?, Dan Sullivan, Robert W. Smith, E. J. Kemnitz, Kevin Barton, Robert M. Graham, Raymond A. Guenther, Larry Webber

Chemistry Faculty Publications

Every student who studies atmospheric pressure in physics or chemistry learns the principles behind the construction of barometers. Cistern barometers, such as those found in most laboratories, consist of a long glass tube containing an inverted column of liquid having an open end in a cistern of the liquid. Students learn that the column of liquid is supported by air pressure and is equal in weight to a column of air of the same diameter.

Statistical Analysis Of Visible Absorption Spectra And Mass Spectra Obtained From Dyed Textile Fibers, Katie Margaret White

Electronic Theses and Dissertations

The National Academy of Sciences recently published a report which calls for improvements to the field of forensic science. Their report criticized many forensic disciplines for failure to establish rigorously-tested methods of comparison, and encouraged more research in these areas to establish limitations and assess error rates. This study applies chemometric and statistical methods to current and developing analytical techniques in fiber analysis. In addition to analysis of commercially available dyed textile fibers, two pairs of dyes are selected based for custom fabric dyeing on the similarities of their absorbance spectra and dye molecular structures. Visible absorption spectra for all …

Localized Surface Plasmon Resonance Enhanced Magneto-Optical Activity In Core-Shell Fe-Ag Nanoparticles, L. Wang, K. Yang, C. Clavero, A. J. Nelson, K. J. Carroll, E. E. Carpenter, R. A. Lukaszew

Chemistry Publications

Metallic nanoparticles (NPs) are suitable platforms for miniaturized biosensing based on their optical and magneto-opticalproperties. It is possible to enhance the sensitivity of specific kinds of NPs by exploiting their optical and magneto-opticalproperties under suitable external magnetic field modulation. Here, the magneto-opticalproperties of Fe–Ag core-shell ferromagnet-noble metal NPs have been investigated as a function of the incident light frequency. For Fe–Ag NPs with a concentration ratio around 25:75, an optical absorption band centered at 3 eV due to localized surface plasmon resonance (LSPR) excitation is observed. A strong enhancement of the Faraday rotation is also observed, greatly exceeding the value …

Spectrally Tunable Magnetic Nanoparticles Designed For Distribution/Recollection Applications, Nicholas B. Mcdowall, James R. Wilkins, Kyler J. Carroll, Jarrod D. Edwards, Jean D. Nelson, Everett E. Carpenter, Garry P. Glaspell

Chemistry Publications

The comprehensive goal of this research is the synthesis and characterization of nanomaterials that are spectrally tunable in terms of their electromagnetic signal, are robust, magnetic (allowing their piloted movement), and have the potential to be functionalized for the detection of CBRNE threats. Various chemical methods were utilized for synthesis of magnetic (iron) and luminescent rare earth (RE) components, and their mixtures. Effects of integrating an iron core into RE luminescent lattices (excited by UV, emit in the VIS) were investigated. The determination of the optimum balances between magnetic and luminescent components such that the magnetism was maximized while maintaining …