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Articles 30331 - 30360 of 33369
Full-Text Articles in Entire DC Network
Purification And Analysis Of Protein Synthetic Initiation Factors From Volvox Carteri, Kathie L. Pooler
Purification And Analysis Of Protein Synthetic Initiation Factors From Volvox Carteri, Kathie L. Pooler
Honors Theses
Volvox carteri, a multi-celled green algae, can grow synchronously given a sixteen hour light period followed by an eight hour dark period, a cycle which is repeated for a 48 hour growth cycle total. Near the end of each light period, reproductive cells divide rapidly resulting in the differentiation of ceIls. When the dark period begins, this differentiation stops and the cells remain dormant with little protein synthesis or differentiation occurring. Immediately after the lights come back on, however, the cells again undergo rapid protein synthesis and complete their differentiation. Previous studies have concluded that Volvox carteri discontinue protein synthesis …
Neutron-Scattering Study Of Librations And Intramolecular Phonons In Rb_{2.6}K_{0.4}C_{60}, D. Reznik, W. A. Kamitakahara, D. A. Neumann, J. R. D. Copley, J. E. Fischer, Robert M. Strongin, M. A. Cichy, Amos B. Smith Iii
Neutron-Scattering Study Of Librations And Intramolecular Phonons In Rb_{2.6}K_{0.4}C_{60}, D. Reznik, W. A. Kamitakahara, D. A. Neumann, J. R. D. Copley, J. E. Fischer, Robert M. Strongin, M. A. Cichy, Amos B. Smith Iii
Chemistry Faculty Publications and Presentations
We report the results of inelastic neutron-scattering measurements on Rb2.6K0.4C60. Librational modes were observed as broad peaks with maxima between 4.1 and 4.7 meV, as the temperature is lowered from 300 to 12 K. As in K3C60, no change in the width or position of the librational peak was observed when the sample was cooled through the superconducting transition. Thus any coupling of the librations to electronic states is small. The magnitude of the orientational potential barrier was estimated from the librational peak frequency. A flat background observed in the …
Kinetic And Chemical Modification Studies On Malate Dehydrogenase From E. Coli, Fang Jenny Zhao
Kinetic And Chemical Modification Studies On Malate Dehydrogenase From E. Coli, Fang Jenny Zhao
Masters Theses
Malate dehydrogenase (MDH) is the enzyme which catalyzes the conversion of malate to oxaloacetate in the TCA cycle. The object of this research was to discipher the mechanism of the reaction and the function of the enzyme. MDH from E. Coli was purified and analyzed by chemical modification studies using diethylpyrocarbonate. Results indicate the existence of a histidine residue at the active site necessary for catalysis. From kinetic studies, a group required for catalysis with a pKa of 8.5 was observed, which we believe to be a histidine residue. These studies indicate that MDH from E. Coli has a …
Macroporous Polymer Synthesis And Characterization: The Role Of Molecular Recognition In The Regioselectivity Of Sucrose Reactions, Gilbert Joshua Matare
Macroporous Polymer Synthesis And Characterization: The Role Of Molecular Recognition In The Regioselectivity Of Sucrose Reactions, Gilbert Joshua Matare
Masters Theses
Molecular recognition has recently emerged as a unique technique for making synthetic polymers with selective binding cavities which can stereoselectively and regioselectively bind to a template molecule in a fashion similar to natural enzymes and antibodies. Its industrial applications in chemistry and biomedicine have been recently exploited. Typical examples include the resolution of amino acids, enantio-separation of racemates and bioactive molecules, selective binding of metal ions and in HPLC investigations. Our research is focused on applying molecular recognition studies to improve the regioselectivity of sucrose reactions.
Sucrose is an abundant industrial raw material of immense industrial importance however, its full …
A Spectroscopic Study Of Nitrogen, Nitrogen/Helium And Fluorobenzenes In A Corona Supersonic Discharge, Jing-Chen Luo
A Spectroscopic Study Of Nitrogen, Nitrogen/Helium And Fluorobenzenes In A Corona Supersonic Discharge, Jing-Chen Luo
Dissertations
No abstract provided.
Lithium Binding To Human Rbc Membranes And Substrates Of Second Messenger Systems, Qinfen Rong
Lithium Binding To Human Rbc Membranes And Substrates Of Second Messenger Systems, Qinfen Rong
Dissertations
No abstract provided.
An Investigation Into Clay Intrinsic Properties, Surface Modifications And Applications, G Robert Goss
An Investigation Into Clay Intrinsic Properties, Surface Modifications And Applications, G Robert Goss
Dissertations
No abstract provided.
Segmental Motions Of Oxidized Human Erythrocyte Spectrin-Actin: A Spin Label Epr Study, Benito O. Kalaw
Segmental Motions Of Oxidized Human Erythrocyte Spectrin-Actin: A Spin Label Epr Study, Benito O. Kalaw
Dissertations
No abstract provided.
Synthesis Of Enantioenriched Piperidine-Based, Spirocyclic Analogues Of Af64a And Acetylcholine, Nam Huh
Synthesis Of Enantioenriched Piperidine-Based, Spirocyclic Analogues Of Af64a And Acetylcholine, Nam Huh
Dissertations
No abstract provided.
Development And Functional Properties Of Intramolecular Crosslinked Hemoglobin, Qunyang Zhang
Development And Functional Properties Of Intramolecular Crosslinked Hemoglobin, Qunyang Zhang
Dissertations
No abstract provided.
The Effect Of Encapsulated Antibodies On Spontaneous Translocation Of A Protein Presequence Into Synthetically Produced Phospholipid Vesicles, Robert Bellin
Honors Theses, 1963-2015
The cytochrome oxidase subunit IV (CoxIV) protein presequence has been found by previous researchers to target proteins to the mitochondria of the cells and associate with or translocate across a membrane bilayer. In this study, the effects of encapsulating antibodies against the presequence within phospholipid vesicles on this association or translocation was studied. Kinetic and thermodynamic theories were developed which predict a higher level of association or translocation of the protein presequence into these antibody containing vesicles. Antibodies against the CoxIV presequence were produced in two rabbits and purified with a Protein A affinity column. Phospholipid vesicles were created with …
5-Acetyl[2.2]Paracyclophane, Sergey V. Lindeman, Yuri T. Struchkov, Vyacheslav N. Guryshev
5-Acetyl[2.2]Paracyclophane, Sergey V. Lindeman, Yuri T. Struchkov, Vyacheslav N. Guryshev
Chemistry Faculty Research and Publications
The title compound 5-acetyltricyclo[8.2.2.24,7]hexa-deca-4,6,10,12,13,15-hexaene, C18H18O,is the first example of a mono-π-substituted [2.2]paracyclophane to be structurally characterized. The average bending angles are α = 13.2 and β = 9.9°. The distance between the 'bottoms' of the practically parallel boat-like benzene nuclei is 3.098(2) Å. The π conjugation between the acetyl group and the substituted benzene cycle is negligible (rotation angle ca 45°) because of steric hindrance.
An M-Carboranedicarboxylic Acid Dianilide, Sergey V. Lindeman, Georgii A. Kats, Lyudmila G. Komarova
An M-Carboranedicarboxylic Acid Dianilide, Sergey V. Lindeman, Georgii A. Kats, Lyudmila G. Komarova
Chemistry Faculty Research and Publications
The crystal structure of the 'non hydrogen-bonded' (according to IR data) polymorph of 1,7-bis(phenylcarbamoyl)-1,7-dicarba-closo-dodecaborane(12), C16-H22B10N2O2, has been determined. The two phenylamide groups have a Z configuration [the torsion angles 0-C-N-C are -2.3 (5) and -3.0 (5)°]. As a result both 'active' protons of these groups are almost completely shielded by other H atoms of the neighbouring carborane nucleus and phenyl substituents, and, therefore, no hydrogen-bonding contacts are found.
N1-Acetyl-3'-Methylandrosta-4,16-Dieno[16,17-D]Pyrazole-3-One, Sergey V. Lindeman, Alexandr I. Yanovsky, Ezequiel Huipe Nava, Alexey V. Kamernitzky, Alina V. Skorova, Irina V. Vesela
N1-Acetyl-3'-Methylandrosta-4,16-Dieno[16,17-D]Pyrazole-3-One, Sergey V. Lindeman, Alexandr I. Yanovsky, Ezequiel Huipe Nava, Alexey V. Kamernitzky, Alina V. Skorova, Irina V. Vesela
Chemistry Faculty Research and Publications
In an attempt to find the structural features promoting the thermal isomerization of the N-acylated steroid [16,17-d]pyrazoles into [17,16-c]pyrazole derivatives,the X-ray structure analysis of the title compound, C23H30N2O3, (1), has been carried out. The steroid moiety of (I) has the usual conformation. The dihedral angle between the planar pyrazole ring and the N-acetyl group is very small [5.6 (2)°], but the amide C-N bond seems to be substantially elongated [1.404 (3) Å ]. The d-pyrazole ring junction via a double bond leads to deformations of …
Surface Flow Structure Of The Gulf Stream From Composite Imagery And Satellite-Tracked Drifters, C. P. Mullen, A. D. Kirwan Jr.
Surface Flow Structure Of The Gulf Stream From Composite Imagery And Satellite-Tracked Drifters, C. P. Mullen, A. D. Kirwan Jr.
CCPO Publications
A unique set of coutemporaneous satellite-tracked drifters and five-day composite Advanced Very High Resolution Radionmeter (AVHRR) satellite imagery of the North Atlantic has been analyzed to examine the surface flow structure of the Gulf Stream. The study region was divided into two sections, greater than 37 degrees N and less than 37 degrees N, in order to answer the question of geographic variability. Fractal and spectral analyses methods were applied to the data. Fractal analysis of the Lagrangian trajectories showed a fractal dimension of 1.21 +/- 0.02 with a scaling range of 83 - 343 km. The fractal dimension of …
Synthesis And Characterization Of Binuclear And Unsymmetrical Phthalocyanines, Jiang Yang
Synthesis And Characterization Of Binuclear And Unsymmetrical Phthalocyanines, Jiang Yang
Doctoral Dissertations
"The metal free planar binuclear phthalocyanines sharing a benzene or naphthalene ring have been synthesized and characterized. The position of Q band of binuclear phthalocyanine sharing a naphthalene ring is red shifted compared to binuclear phthalocyanine sharing a benzene ring. The compounds are shown to form the liquid crystal mesophases at room temperature.
The unique unsymmetrical phthalocyanines with steric hindrance tetraphenyl or “opposite” octaphenyl substitution have been synthesized with the aid of computer modeling. The compounds are characterized by UV-visible near IR absorption and NMR spectroscopy. Mesophase is observed by optical microscopy and differential scanning calorimetry.
The aggregation behavior has …
The Corrosive Effects Of Salt Spray On Electrolytic Zinc Plated Mechanical Fasteners: The Case Of Clear Chromate And Yellow Dichromate Coatings On Medium Carbon Plated Bolts, Souleymane Boukari
The Corrosive Effects Of Salt Spray On Electrolytic Zinc Plated Mechanical Fasteners: The Case Of Clear Chromate And Yellow Dichromate Coatings On Medium Carbon Plated Bolts, Souleymane Boukari
Dissertations and Theses @ UNI
The purpose of this study was to evaluate the relationship between plating thickness and corrosion resistance of zinc coated medium carbon steel bolts under salt spray moisture conditions. Two types of zinc coatings were chosen for the study: the clear chromate zinc and the yellow dichromate zinc. One hundred and eighty 3/8-16 x 5 3/4 inch medium carbon steel bolts were selected for the test and divided into groups of 18. Two types of salt solution were used in the study: the low salt and the high salt. Bolts with various coatings tested with low salt concentration were composed of …
Enhancement Of A Time-Of-Flight Mass Spectrometer Using A Bipolar Pulsed Electrostatic Particle Guide And A Novel Ms-Ms Correlation Technique, Craig Lavern Just
Enhancement Of A Time-Of-Flight Mass Spectrometer Using A Bipolar Pulsed Electrostatic Particle Guide And A Novel Ms-Ms Correlation Technique, Craig Lavern Just
Dissertations and Theses @ UNI
Detector saturation and the lack of mass spectrometry-mass spectrometry (MSMS) correlation techniques has limited the utility of time-of-flight mass spectrometry (TOF-MS). This research focused on solving these problems with the use of an electrostatic particle guide and a novel two-dimensional correlation technique. Microchannel plate detectors that are used with TOF-MS have been shown to be susceptible to saturation due to high ion influxes. Matrix assisted laser desorption ionization (MALDI), as used for this research, produces a large number of low molecular weight ions that cause excessive detector saturation. This problem was addressed with the development of a bipolar pulsed electrostatic …
Catalytic Oxidation Of Chlorinated Hydrocarbons Over Powdered Transition Metal Oxide, Sanmei Xu
Catalytic Oxidation Of Chlorinated Hydrocarbons Over Powdered Transition Metal Oxide, Sanmei Xu
Theses
This study addresses the ability of powdered transition metal oxides such as manganese oxide, iron oxide and copper oxide to catalytically oxidize low concentrations of chlorinated hydrocarbons with air. The catalytic oxidation of trichloroethylene and dichloromethane in a tubular reactor system was evaluated experimentally as a function of temperature and space velocity. Gas chromatography with electron capture detector and flame ionization detector was used for quantitative analysis of feed and product streams. Gas chromatography/mass spectrometry and gas chromatography/Fourier transform infrared spectroscopy were used to identify all oxidation products. The results indicate that over 99% conversion of trichloroethylene is achieved at …
Detection Of Alzheimer's Disease And Other Diseases Using An Improved Photoaffinity Labeling Method, Boyd E. Haley
Detection Of Alzheimer's Disease And Other Diseases Using An Improved Photoaffinity Labeling Method, Boyd E. Haley
Chemistry Faculty Patents
A method for diagnosing a neurological disease comprising detecting a neurological disease-specific biochemical marker macromolecule within a sample of extracted cerebral spinal fluid is disclosed. In particular, a radioactively labeled photoaffinity probe is used to diagnose a neurological disease. For instance, Alzheimer's disease can be diagnosed by detecting a disease-specific protein having a molecular weight of about 42,000 daltons, i.e., glutamine synthetase.
Atmospheric Hydrocarbon Analysis, Dawei Han
Atmospheric Hydrocarbon Analysis, Dawei Han
Dissertations and Theses
This treatise studied two correlated important issues in atmospheric chemistry: real-time monitoring of ambient air and removal mechanisms of atmospheric hydrocarbons. An analytical system was designed for the purpose of identification and measurement of sub-ppb level hydrocarbons of different reactivities in air samples. This analytical system was then applied to a series of smog-chamber studies which simulated the removal of reactive hydrocarbons from the atmosphere by reaction with hydroxyl radicals. Six representative atmospheric hydrocarbons (hexane, octane, toluene, m-xylene, a-xylene and mesitylene) were selected for these experiments. The experimental data indicated that the decay of atmospheric hydrocarbons under laboratory conditions is …
Senior Theses: Department Of Physical Sciences, Frank Baldridge, Billy B. Stapleton, James Bond, Mark A. Blair
Senior Theses: Department Of Physical Sciences, Frank Baldridge, Billy B. Stapleton, James Bond, Mark A. Blair
Morehead State Theses and Dissertations
1993 Fall Semester Senior Theses for the class Physical Science 471:
Petrologic Classification of Igneous and Metamorphic Rocks by Frank Baldridge
X -Ray Analysis of Cave Sediments From Pigeon Water Cave of Northeastern Pine Mountain by Billy B. Stapleton
The Correlation of Stream-deposited Breccias In Bat Cave, Carter Caves, Kentucky by James Bond
Jointing and Faulting in Selected Areas of Eastern Kentucky by Mark A. Blair
Coal Sulfur Forms Determination Using Thermal Analysis Methods, Bucheng Wang
Coal Sulfur Forms Determination Using Thermal Analysis Methods, Bucheng Wang
Masters Theses & Specialist Projects
By optimizing parameters including temperature, reaction time, reagent concentration and pressure, the optimum conditions for the mild oxydesulfurization of coals were determined to be 150°C-200"C and 10 atmospheres oxygen in aqueous slurries of coal reacted with 1 M NH4OH for 1.5-2 hours. The total amount of sulfur removed from -60 mesh coals ranges from 51% to 78% with a mean of 64%, while the amount of inorganic sulfur removed from the coals ranged from 66% to 91% with a mean of 77%. The amount of organic sulfur removed from the samples ranged from 36% to 50% with a …
A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane
A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane
Electronic Theses and Dissertations
Extraction of the lipids of Legionella pneumophila yields phases unlike those produced from other Gram-negative bacteria. A viscous interface forms between the aqueous (wash) and organic phases. More than half of the hydroxylated fatty acids were found distributed between the aqueous phase and the interfacial material, fractions in which such constituents have not been reported in other Gram-negative species. It was further observed that after the material from the aqueous/interfacial phase was dissolved in methanol or chloroform/methanol (2:1 (V/V)), the addition of acetone would create a white, flocculent precipitate. Analyses showed that the supernatant contained fatty acids that were nonhydroxylated …
Separation Of Copper And Iron In Natural Waters By Solid-Phase Extraction, Charles Bui
Separation Of Copper And Iron In Natural Waters By Solid-Phase Extraction, Charles Bui
Masters Theses
A separation scheme has been developed by utilizing Solid-Phase Extraction cartridges in order to isolate and characterize the charge of metals and their complexes in natural waters. These species can be analyzed by Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma (ICP), and Ultraviolet-Visible Spectrophotometry (UVVIS).
This separation scheme would permit the determination of the concentration of metals, as well as providing information about the forms in which the metals exist, e.g., charge of metallic complexes.
Synthetic metal complexes were prepared in the laboratory in order to study the separation scheme as well as trying to understand the binding stability of …
Thermodynamic Properties Of Mixtures Of Aqueous Solutions Of Hydrochloric Acid And Cadmium Chloride, Copper Chloride, Manganese Chloride, And Zinc Chloride, Samia A. Kosa
Masters Theses
The densities of mixtures of aqueous solutions of hydrochloric acid and cadmium chloride, copper chloride, manganese chloride, and zinc chloride have been measured at constant ionic strengths of 1.0 and 3.0 molal at 25 °C. In the case of HCl, CdCl2 , and ZnCl2 the literature data were refit using Pitzer' s apparent molal volume equation and the binary solution parameters were determined. Density data were used to determine the volume of mixing (∆Vm). Data from Torok and Berecs were combined with our data for the mixtures with CuCl2 and MnCl2. Pitzer's volume …
Neutron-Diffraction And Mössbauer-Effect Studies Of Pr₂(Fe₁₋ₓmnₓ)₁₄B, Oran Allan Pringle, Jie Fu, Gary J. Long, William Joseph James, Decai Xie, William B. Yelon, Fernande Grandjean
Neutron-Diffraction And Mössbauer-Effect Studies Of Pr₂(Fe₁₋ₓmnₓ)₁₄B, Oran Allan Pringle, Jie Fu, Gary J. Long, William Joseph James, Decai Xie, William B. Yelon, Fernande Grandjean
Physics Faculty Research & Creative Works
A neutron-diffraction investigation of a series of Pr2(Fe 1-xMnx)14B samples, with x values of 0.00, 0.11, 0.22, 0.30, and 0.35, reveals a preference for the manganese to occupy the 8j2 transition-metal site,the transition-metal site with the largest Wigner-Seitz cell volume. Similar site occupancies have been reported previously for Er2(Fe1-xMnx) 14B and Y2(Fe1-xMnx) 14B. An analysis of the 295-K Mössbauer spectrum of Pr2(Fe0.89Mn0.11)14B indicates that the internal hyperfine fields on the …
Monte Carlo Simulation Of The Solid To Super Liquid Phase Transition Of Langmuir Monolayers Using Cross-Section Potentials, D.R. Swanson, Robert J. Hardy, Craig J. Eckhardt
Monte Carlo Simulation Of The Solid To Super Liquid Phase Transition Of Langmuir Monolayers Using Cross-Section Potentials, D.R. Swanson, Robert J. Hardy, Craig J. Eckhardt
Craig J. Eckhardt Publications
A cross-section potential which models the interaction of two planar objects of prescribed shape is developed and used to model the interactions of amphiphiles in vertical phases of Langmuir monolayers. The results of Monte Carlo simulations of an isobaric-isothermal ensemble show qualitative agreement with experiment. The model system undergoes a continuous, bound-to-free rotator transition between phases of the same symmetries as the solid (S) and super liquid (LS) phases exhibited by fatty acid films.
The Development Of New Methods For Coal Sulfer Forms & Sulfur In Ash Determination, Robert Forsythe
The Development Of New Methods For Coal Sulfer Forms & Sulfur In Ash Determination, Robert Forsythe
Masters Theses & Specialist Projects
The development of new procedures to determine the amount and/or types of sulfur in coal and coal products is an ongoing process for coal scientists This development is driven by the problems and inconveniences of the current ASTM methods In this thesis, the work done at Western Kentucky University in the development of two new sulfur determination procedures will be described. The first procedure can be used as an alternative method for coal sulfur forms analysis with results comparable to the ASTM method. This procedure involves heating the coal samples at 365°C and 440°C for thirty minutes to selectively remove …
Brillouin-Scattering Study Of The Elastic Constants Of Phenothiazine Through The Phase Transition, J. Sartwell, Craig J. Eckhardt
Brillouin-Scattering Study Of The Elastic Constants Of Phenothiazine Through The Phase Transition, J. Sartwell, Craig J. Eckhardt
Craig J. Eckhardt Publications
It has been proposed that single crystals of phenothiazine undergo a proper ferroelastic phase transition: Pnma(D2h)→P21/c (C2h). This premise is in conflict with Brillouin-scattering studies from both quasi- and high-symmetry longitudinal and transverse acoustic modes reported here. The C55 elastic constant of phenothiazine as an orthorhombic crystal at ambient conditions shows no temperature dependence. The inelastic, light-scattering spectra support an order-disorder phase transition; no significantly unstable acoustic phonons were observed through the phase transition. Laser diffraction from structural domains reveals that the crystal is polysynthetically …