Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Materials Chemistry (2395)
- Engineering (2276)
- Materials Science and Engineering (1916)
- Engineering Science and Materials (1759)
- Electrical and Computer Engineering (1313)
-
- Power and Energy (1280)
- Chemical Engineering (863)
- Catalysis and Reaction Engineering (816)
- Analytical Chemistry (652)
- Nanoscience and Nanotechnology (648)
- Physics (351)
- Organic Chemistry (234)
- Computational Chemistry (214)
- Inorganic Chemistry (182)
- Other Chemistry (175)
- Atomic, Molecular and Optical Physics (142)
- Environmental Chemistry (139)
- Environmental Sciences (134)
- Life Sciences (132)
- Biological and Chemical Physics (123)
- Biochemistry, Biophysics, and Structural Biology (98)
- Semiconductor and Optical Materials (98)
- Oil, Gas, and Energy (92)
- Medicine and Health Sciences (83)
- Biochemistry (71)
- Polymer Chemistry (64)
- Medicinal-Pharmaceutical Chemistry (53)
- Institution
-
- Chinese Chemical Society | Xiamen University (2392)
- University of New Mexico (228)
- University of Nevada, Las Vegas (189)
- Old Dominion University (89)
- University of Nebraska - Lincoln (87)
-
- University of Arkansas, Fayetteville (75)
- Chapman University (74)
- University of Kentucky (74)
- City University of New York (CUNY) (55)
- University of Connecticut (48)
- Virginia Commonwealth University (46)
- University of Dayton (44)
- Missouri University of Science and Technology (38)
- Louisiana State University (37)
- University of Denver (35)
- Technological University Dublin (31)
- University of Mississippi (31)
- Wayne State University (31)
- Purdue University (29)
- San Jose State University (27)
- Kennesaw State University (26)
- West Virginia University (26)
- Clemson University (25)
- The British University in Egypt (25)
- Taylor University (24)
- The University of San Francisco (23)
- The University of Southern Mississippi (23)
- Marquette University (22)
- Western Kentucky University (22)
- Eastern Illinois University (19)
- Keyword
-
- Electrochemistry (96)
- Electrocatalysis (89)
- Cyclic voltammetry (83)
- Electrodeposition (67)
- Oxygen reduction reaction (66)
-
- Lithium ion battery (65)
- Chemistry (53)
- Supercapacitor (51)
- Corrosion (46)
- Electrochemical performance (42)
- Cathode material (41)
- Spectroscopy (39)
- Lithium-ion battery (38)
- DFT (37)
- Electrochemical impedance spectroscopy (35)
- Lithium-ion batteries (35)
- Fuel cell (34)
- Molecular dynamics (33)
- Chemistry and Biochemistry (31)
- College of Natural Science and Mathematics (31)
- Lithium ion batteries (30)
- Carbon nanotubes (29)
- Fuel cells (29)
- Nanoparticles (29)
- Pure sciences (29)
- Modified electrode (28)
- Adsorption (27)
- Catalysis (27)
- Density functional theory (27)
- Electrolyte (27)
- Publication Year
- Publication
-
- Journal of Electrochemistry (2392)
- Chemistry and Chemical Biology ETDs (219)
- Chemistry Faculty Publications (87)
- Theses and Dissertations (67)
- Electronic Theses and Dissertations (66)
-
- Separations Campaign (TRP) (64)
- Xiao Cheng Zeng Publications (59)
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (52)
- Chemistry and Biochemistry Faculty Research (47)
- Chemistry Education Materials (46)
- Chemistry & Biochemistry Faculty Publications (38)
- Honors Theses (37)
- Dissertations, Theses, and Capstone Projects (36)
- Environmental Studies Faculty Publications (35)
- Dissertations (33)
- LSU Doctoral Dissertations (33)
- Theses and Dissertations--Chemistry (33)
- Wayne State University Dissertations (30)
- Articles (28)
- Graduate Theses and Dissertations (28)
- Faculty Publications (26)
- Faculty Publications, Chemistry (26)
- Graduate Theses, Dissertations, and Problem Reports (ETD) (26)
- All Dissertations (25)
- Master's Theses (25)
- Chemistry & Biochemistry Student Projects (24)
- Chemical Engineering (23)
- TeachEPR Submissions (23)
- Chemistry & Biochemistry Faculty Works (21)
- Journal of the Arkansas Academy of Science (21)
- Publication Type
- File Type
Articles 4321 - 4350 of 4499
Full-Text Articles in Physical Chemistry
Isolation And Characterization Of Frullanolide From Frullania Franciscana (Howe), Marshall Stuart Sass
Isolation And Characterization Of Frullanolide From Frullania Franciscana (Howe), Marshall Stuart Sass
Dissertations and Theses
Investigation of the ether extract of the liverwort Frullania franciscana (Howe) resulted in the isolation of the sesquiterpene lactone frullanolide. The separation techniques of thin-layer chromatography, dry column chromatography, and liquid column chromatography were evaluated. Only liquid column chromatography was found useful. Fractions from alumina liquid column separations had infrared spectra which resembled the published spectrum of frullanolide. The identity of the compound obtained from F. franciscana (Howe) was established after extensive purification by comparison of its infrared and nuclear magnetic resonance spectra with published spectra of frullanolide.
Effects Of N2h4 On The Transition Temperature In The Anisotropic Superconductor Tase3, K. Yamaya, T. H. Geballe, Juana Vivó Acrivos, J. Code
Effects Of N2h4 On The Transition Temperature In The Anisotropic Superconductor Tase3, K. Yamaya, T. H. Geballe, Juana Vivó Acrivos, J. Code
Faculty Publications, Chemistry
No abstract provided.
Mott G-Ratios In Rbx(Nh3)1-X And Oxidation State Of Rubidium Compounds From Xas, Juana Vivó Acrivos, K. Hathaway, A. Robertson, M. P. Klein, A. Thompson
Mott G-Ratios In Rbx(Nh3)1-X And Oxidation State Of Rubidium Compounds From Xas, Juana Vivó Acrivos, K. Hathaway, A. Robertson, M. P. Klein, A. Thompson
Faculty Publications, Chemistry
The x-ray absorption spectra (XAS) of Rb metal, Rh,("JH,J, ,, 2H-NbSe2Rb111x and RbBr near the Rb K-edge have been used to ascertain that the oxidation state V of rubidium dissolved in ammonia and intt:rcalated in the layer compound is in the range 0 < V < I. Theobservededge shifts with temperature for semimctals are explainedin terms of the population of band states, and the ratio of the density states near the mobility edge over that calculated for a free electron model, i.e. the Mott ratio g, is ascertained using a semiempirical relation developed for the x-ray absorbance from Is levels to empty states ncar the mobility edge.
Conduction Band Symmetry In Ta Chalcogenides From Ta L Edge X-Ray Absorption Spectroscopy (Xas), Juana Vivó Acrivos, S.S. P. Parkin, J. Code, J. Reynolds, K. Hathaway, H. Kurasaki, E. Marseglia
Conduction Band Symmetry In Ta Chalcogenides From Ta L Edge X-Ray Absorption Spectroscopy (Xas), Juana Vivó Acrivos, S.S. P. Parkin, J. Code, J. Reynolds, K. Hathaway, H. Kurasaki, E. Marseglia
Faculty Publications, Chemistry
No abstract provided.
Spectroscopic Studies Of Pre-Mixed Hydrocarbon Flame Plasmas, Tsao-Chin C. Huang
Spectroscopic Studies Of Pre-Mixed Hydrocarbon Flame Plasmas, Tsao-Chin C. Huang
Masters Theses
This thesis contains two different studies.
Chapter 1, "Infrared Emission Spectrum of the Hydroxyl Radical.", is in collaboration with Dr. Giles L. Henderson and Mr. Chun-Sheng Ko. This chapter has been submitted and accepted for publication by the Journal of Chemical Education.
In this chapter, we describe a rather novel physical chemistry experiment in which ab initio potential parameters for the OH radical are compared with those obtained from the ir emission spectrum of an oxy-acetylene welding torch.
Chapter 2, "A Preliminary Spectroscopic Study of Field-Induced Ion Movements in Flame Gases.", describes the effects of longitudinal electric fields on CH …
The Use Of Thermal Analysis In The Identification And Characterization Of Fibers Of Forensic Interest, Ronald J. Coffey
The Use Of Thermal Analysis In The Identification And Characterization Of Fibers Of Forensic Interest, Ronald J. Coffey
All-Inclusive List of Electronic Theses and Dissertations
This study investigates the use of thermal analysis for the identification and characterization of fibers for forensic purposes. Fibers such as polyesters, polyacrylics, polypropylenes and nylon were investigated by Differential Thermal Analysis (D.T.A.) and Thermogravimetric Analysis (T.G.A.) to see if their resulting thermograms were characteristic of each fiber. Also, infrared analysis was performed on each fiber. In addition, such factors as heating rate and sample size along with fiber blends were studied as to their effect on thermograms. As a result of this study several important conclusions may be drawn. Although it was found that for the most part D.T.A. …
Synthesis And Reactivity Of Some Fe(0) And Ru(0) Compounds, Michael E. Hawkins
Synthesis And Reactivity Of Some Fe(0) And Ru(0) Compounds, Michael E. Hawkins
Masters Theses
The catalytic activity of the compounds used in this study, Ru[P(C6H5)3]4 (η2-CH3CN)⋅CH3CN, Ru(CO)[P(C6H5)3]3CH3CN, Ru(CO)2[P(C6H5)3]3, Fe(CO)2[P(C6H5)3]3 was compared using the isomerization of allylbenzene to β-methylstyrene as the test reaction. The measured decreasing order of reactivity for these complexes is: Ru(CO)[P(C6H5)3]3CH3CN > Ru[P(C6H5)3]4 (η …
A Numerical Method For The Solution Of The Schrödinger Equation By A Trial Wavefunction Improvement Formula, Chun-Sheng Ko
A Numerical Method For The Solution Of The Schrödinger Equation By A Trial Wavefunction Improvement Formula, Chun-Sheng Ko
Masters Theses
A numerical method and corresponding computer algorithm for solving the one-dimensional radial Schrödinger equation to any desired accuracy is developed. The method uses a finite difference scheme in which an initial trial wavefunction is digitalized over a lattice covering the region of integration. The values of a rough solution are then altered at each lattice point by a simple improvement formula decreasing the value of the variational energy until the desired minimum is reached. The accuracy of these solutions depends only on the grid size. This method is characterized and tested with a harmonic oscillator potential. Practical evaluations and applications …
Analytical Applications Of Ultrasonic Velocity Using Three-Transducer Phase-Shift Detection, Chuan Chen
Analytical Applications Of Ultrasonic Velocity Using Three-Transducer Phase-Shift Detection, Chuan Chen
Chemistry and Chemical Biology ETDs
A new method for determining ultrasonic velocity and its application as a high-performance liquid chromatography (H.P.L.C.) detector is developed. The method involves in using a threetransducer phase-shift device where two transducers alternately transmit 1-MHz continuous wave signals to the same receiver. Ultrasonic velocity can be calculated from the phase-shift difference between the two cell paths. When the device is used as an H.P.L.C. detector, the reciprocal of the phase-shift difference between the two cell paths is converted to an electrical signal and recorded on a chart paper with respect to retention time. The theoretical principles are discussed and the appropriate …
Site Specificity In The Intercalation Of Antitumor Antibiotics With Dna, Martin Bradford Jones
Site Specificity In The Intercalation Of Antitumor Antibiotics With Dna, Martin Bradford Jones
Chemistry and Chemical Biology ETDs
Many planar molecules or molecules with planar moieties have been shown to bind to DNA by intercalation, which can be defined as the insertion of a planar moiety between adjacent bases on the DNA strand, reading in the 3'-5' direction, accompanied by a partial unwinding and elongation of the helix in the immediate vicinity of the intercalation site. Intercalation raises the question of specificity of binding of the drug to DNA, since there are 16 possible intercalation sites in normal double-stranded DNA. The conformational changes (elongation and unwinding) associated with intercalation make circular dichroism (CD) an excellent technique for studying …
The Synthesis Of C₄ And C₅ 13c-Labeled Benzo[A]Pyrene, Benzo[A]Pyrene-4, 5-Oxide And Derivatives. Studies Of The Reactions Of Benzo[A]Pyrene-4, 5-Oxide Using 13cnmr, Mark David Hylarides
The Synthesis Of C₄ And C₅ 13c-Labeled Benzo[A]Pyrene, Benzo[A]Pyrene-4, 5-Oxide And Derivatives. Studies Of The Reactions Of Benzo[A]Pyrene-4, 5-Oxide Using 13cnmr, Mark David Hylarides
Chemistry and Chemical Biology ETDs
Benzo[a]pyrene (BAP), BAP-4,5-oxide, and other derivatives which are 13c-labeled in the 4-and 5-positions were synthesized. The synthetic scheme involves an initial reaction of the lithioenolate of ethyl acetate-1-13c or ethyl acetate-2-13c with l,2-dihydrochrysen4(3H)-one. Subsequent dehydration and dehydrogenation gave ethyl 4-chryseneacetate-1-C (or 2-C). Partial reduction to the aldehyde 13 13 followed by cyclization gave BAP-5-C (and 4-C). Toe synchesis of 13 BAP-4,5-oxide-4-13c (and 5-c) involved saponification of ethyl 4-chryseneacetate-1-13c (and 2-13c), an intermediate in the synthesis of BAP, followed by cyclization of the resultant acid to BAP-5-ol13 s-c (and 4-13c). The crude phenol was oxidized to the o-quinone. Further reduction of …
Kinematics And Thermodynamics Of Nickel(Ii)-Glycine Complexes Using Carbon Magnetic Resonance, Donald Frederick Shepard
Kinematics And Thermodynamics Of Nickel(Ii)-Glycine Complexes Using Carbon Magnetic Resonance, Donald Frederick Shepard
Chemistry and Chemical Biology ETDs
1-13C glycine was studied in nickel(II) solutions using carbon magnetic resonance (CMR). The carboxy bound nickel(II)-glycine complex and the kinetics of complexation between aquated nickel(II) ion and aquated glycine are described. It has been hypothesized that solutions containing no complexation higher than the chelated mono nickel(II)-glycine complex contain five magnetically different glycine species. The effects of these five magnetically different glycine species on the CMR spectra of the nickel(II)-glycine solutions are discussed. The lifetime of the carboxy bound complex is 7.87 x 10-4 sec at 272 K with an activation energy of 9.74 kcal/mole, an activation enthalpy …
Synthesis Of Benzo[A]Pyrene And Derivatives: Labelling Of Positions 1, 2, 3, 11 And 12, Richard S. Bodine
Synthesis Of Benzo[A]Pyrene And Derivatives: Labelling Of Positions 1, 2, 3, 11 And 12, Richard S. Bodine
Chemistry and Chemical Biology ETDs
The ketone, 3, 4-dihydrobenz[a]anthracen-1(2H)-one (1), was prepared in three steps from anthracene. Condensation of the lithioenolate of ethyl acetate with the ketone(1) in tetrahydrofuran at -78°C afforded ethyl (1-hydroxy-1, 2, 3, 4-tetrahydrobenz[a]anthracen-1-yl)acetate (2). Dehydration and dehydrogenation over palladium/charcoal provided ethyl (benz[a]anthracen-1-yl)acetate (3). Reduction of the ester (3) with diisobutylaluminum hydride in toluene at -75°C gave benz[a]anthracen-1-ylacetaldehyde (4) which was cyclized with methanesulfonic acid to benzo[a]pyrene (5). Saponification of the ester (3) gave benz[a]anthracen-1-ylacetic acid (6) which was cyclized with methanesulfonic acid to benzo[a]pyren-11-o1 (7). Oxidation of the phenol (7) with Fremy's salt afforded the quinone, 11, 12-dihydrobenzo[a]pyrene-11, 12-dione (8). Reduction …
The Electrogenerated Chemiluminescence Of Trans-Stilbene Derivatives, James R. Wilson
The Electrogenerated Chemiluminescence Of Trans-Stilbene Derivatives, James R. Wilson
Chemistry and Chemical Biology ETDs
A group of 15 compounds, all structurally related to transstilbene have been studied in systems of electrogenerated chemiluminescence (ECL). The compounds are substituted 2-phenyl indenes, dihydronapthalenes, and dihydrophenanthrenes. Absorption and fluorescence spectra, fluorescence quantum yield, cyclic voltammetry, and ECL were obtained for each compound. The ECL experiments were set up as single and mixed systems which used tripara-tolylamine as the source of cation radicals. Each mixed system was studied in two different solvents, which were acetonitrile and a 1:1 mixture of acetonitrile and benzene. Single systems were studied only in the acetonitrile-benzene solution. Emissions at wavelengths longer than the fluorescence …
Chemiluminescence Studies Of Silicon Fluoride And Uranium Oxide, Russell A. Armstrong
Chemiluminescence Studies Of Silicon Fluoride And Uranium Oxide, Russell A. Armstrong
Chemistry and Chemical Biology ETDs
Spectroscopic studies of the reactions of fluorine with silicon, silane and deuterated silane, and of oxygen with uranium are reported. Chemiluminescence and atomic absorption techniques have been employed to determine the kinetics, photon yields and branching ratios of the chemistry leading to the excited states of the radical SiF. The reaction of silicon vapor with fluorine occurs at nearly a gas kinetic rate (k2=1.3 x 10-10 cc molecule-1 sec-1). The overall system photon yield from the reaction of silane and fluorine to produce SiF(A➔X) and SiF(a➔X) emission were 5 x 10-2% and …
Comparative Enzymology Of Glyoxalase I, Christina Margaret Schimandle
Comparative Enzymology Of Glyoxalase I, Christina Margaret Schimandle
Chemistry and Chemical Biology ETDs
The role of the metal ion in rat erythrocyte glyoxalase I was evaluated. The apoenzyme was formed by dialysis against an EDTA-imidazole buffer. Fluorescence studies of the Mg++- and Mn++-dansylated glyoxalase I's suggest that the metal ion is near the active site of the enzyme and participates in the catalytic reaction. Stereochemical studies of the conversion of methylglyoxal to S-lactoylglutathione with Mg++, Mn++, Co++ and Ni++-glyoxalase I's show that the 0-lactate of S-lactoylglutathione (97±1.5%) is formed. This result suggests that the reaction mechanism is the same with a change …
In Situ Intercalation Of Tas2 In The Electron Microscope, G. Tatlock, Juana Acrivos
In Situ Intercalation Of Tas2 In The Electron Microscope, G. Tatlock, Juana Acrivos
Faculty Publications, Chemistry
Electron diffraction had been used to study the formation of a variety of complex superlattices in the 1T, 2H and 4Hb polytypes of TaS2 during intercalation with hydrazine gas (N2H4), in situ in the electron microscope. Results are presented over the temperature range 15K-360K and are interpreted in terms of scattering from periodic lattice distortions linked to charge density waves. Comparisons are also made with similar effects in both the as-grown crystals and the TaS2 samples containing other adducts.
Synthesis And Studies Of A Carbon-13 Labelled Chemical Carcinogen, Robert E. Royer
Synthesis And Studies Of A Carbon-13 Labelled Chemical Carcinogen, Robert E. Royer
Chemistry and Chemical Biology ETDs
Derivatives of 6-methylbenzo[a]pyrene enriched to 90% carbon-13 at the methyl carbon were synthesized. Reactions of the carcinogen, 6-chloromethylbenzo[a]pyrene, with nucleophiles under solvolytic conditions were studied kinetically and, using labelled 6-chloromethylbenzo[a]pyrene, the reaction products were studied by CMR. The purpose was to characterize the selectivity of the benzo[a]pyrenyl- 6-methyl carbonium ion in its reactions with some simple nucleophiles and with nucleosides and other nucleic acid components.
Although the solvolysis of 6-chloromethylbenzo[a]pyrene in aqueous/organic solution is first order, information about the course of the reaction can be obtained, under certain circumstances, from rate constants. Thus, if the rate of solvolysis is slowed …
Physical Studies Of Hg(Ii) And Ag(I) Dna Complexes, Dawen Ding
Physical Studies Of Hg(Ii) And Ag(I) Dna Complexes, Dawen Ding
Chemistry and Chemical Biology ETDs
The binding of Hg(II) and Ag(I) to the bases of DNA and polynucleotides induces strong absorption and CD bands. From electric dichroism studies, the transition moment of the difference absorption band at 293 nm is in the plane of the bases and has a huge negative CD band at 285 nm; while the corresponding 293 nm difference absorption band of DNA-Ag(I) complex is relatively CD inactive. A second band at 270 nm in the difference absorption spectrum of the DNA-Ag(I) complex has a large associated CD band at 270 nm. This transition is out of the plane of the bases. …
Photochemical Studies Of Hydroxo-Bridged Complexes Of Chromium (Iii), Ronald Raymond Ruminski
Photochemical Studies Of Hydroxo-Bridged Complexes Of Chromium (Iii), Ronald Raymond Ruminski
Chemistry and Chemical Biology ETDs
The acid solution and solid state photolysis in both visible and ultraviolet regions of the spectrum for µ-hydroxo-bis[pentaamminechromium(III)] chloride, and the solution photolysis in the visible and 1 traviolet region of the spectrum for µ-hydroxo-bis[pentaarnrninechr rnium(III)] perchlorate, have been studied. The ultraviolet irradiation of µ-hydroxo-bis[pentaamminechromium(III)] chloride in HCl and CHlO4 produces a redox photoproduct identified as HCrO4-, although the rate of production of HCrO4- in HClO4 is slower than in HCl. Photochemical cleavage of the hydroxo-bridge occurs in the ultraviolet photolysis of µ -hydroxo-bis[pentaanuninechromium(III)] chloride and is 1.9 times faster than the corresponding …
The Effects Of Various Pyrolysis Conditions On The Release Of Products From Green River Oil Shale, Georgia Thomas Fritz
The Effects Of Various Pyrolysis Conditions On The Release Of Products From Green River Oil Shale, Georgia Thomas Fritz
Chemistry and Chemical Biology ETDs
The fusion of oil shales with eutectic mixtures of inorganic salts was studied with the objective of finding a chemical means of releasing the organic material either at a lower temperature or with a lower empirical activation energy (Ea). Experimental techniques by which the pyrolysis of oil shale was studied were thermogravimetry (TG), evolved gas detection (EGD), and pyrolysis/thin-layer chromatography (TLC). The following fused salts were investigated (ratios in mo1%): LiCO3/Na2co3/K2CO3, 43.5/31.5/25.0; KSCN/NaSCN, 73.75/26.25; KSCN/NaSCN, 70/30; Na2SO4/K2SO4/ZnSO4, 29.1/30.2/40.7; NaCl/Na2CO3 …
A Study Of The Gas-Solid Reaction Between Hydrogen Sulfide And Mercury(I) Chloride; Development Of A Method For Determination Of Atmospheric Hydrogen Sulfide, Eric H. De Carlo
A Study Of The Gas-Solid Reaction Between Hydrogen Sulfide And Mercury(I) Chloride; Development Of A Method For Determination Of Atmospheric Hydrogen Sulfide, Eric H. De Carlo
Chemistry & Biochemistry Theses & Dissertations
The possibility of measuring hydrogen sulfide indirectly by measuring the mercury evolved from the gas-solid reaction between hydrogen sulfide and mercury(I) chloride was studied. DMCS treated glass wool was coated with mercurous chloride and used as a conversion material. The response to hydrogen sulfide was studied as a function of concentration and temperature. The possible interference of other sulfur gases and water was examined.
The studies indicated that hydrogen sulfide could be determined at concentrations as low as 15 ppb. It was found that mercaptans would actively interfere with the hydrogen sulfide to mercury conversion, but that sulfur dioxide would …
Determination Of Size Distributions In Heterodisperse Systems Of Homogeneous, Non-Absorbing Spheres From Angular Light Scattering Extrema, Werner Bergman
Determination Of Size Distributions In Heterodisperse Systems Of Homogeneous, Non-Absorbing Spheres From Angular Light Scattering Extrema, Werner Bergman
Wayne State University Dissertations
No abstract provided.
Comparisons Between Oriented Film And Solution Tertiary Structure Of Various Nucleic Acids, Douglas R. C. Priore
Comparisons Between Oriented Film And Solution Tertiary Structure Of Various Nucleic Acids, Douglas R. C. Priore
Chemistry and Chemical Biology ETDs
It was desired to help establish whether or not the tertiary structure of a biomolecule is the same in a crystal (or an oriented film) as it is in solution. Generally it is accepted that the structures in these diverse environments are similar, if not identical. By comparing the extinction coefficients obtained from oriented film data to those obtained from solution data it was hoped that this question might further be resolved. To this end an electric dichroism instrument built in our lab was used to measure the dichroic signal so as to calculate, with the help of the ultraviolet …
Infrared-To-Visible Upconversion In Rare Earth Doped Materials, Deon G. Ettinger
Infrared-To-Visible Upconversion In Rare Earth Doped Materials, Deon G. Ettinger
Chemistry and Chemical Biology ETDs
Upconversion materials have been prepared which may be stimulated by incident 970 nm radiation to emit in the visible region. The couples Yb+3-Ho+3 in a YF3 host and Yb+3-Er+3 in YF3, YPO4, Li3PO4 and Y2O2S hosts have been studied at temperatures from 9K to 273K. For (Y.80Yb.19Er.01)F3 emission bands at 657 nm, 538 nm, 520 nm, 409 nm and 379 nm have been detected and determined to result from 3-, 2-, 2-, 3-, and 3-photon …
Conversion Of Farnesyl Pyrophosphate And Squalene To Sterols By Rat Liver Microsomal Enzymes: Specificity Of Sterol Carrier Protein₁, Kathleen Lobaugh Gavey
Conversion Of Farnesyl Pyrophosphate And Squalene To Sterols By Rat Liver Microsomal Enzymes: Specificity Of Sterol Carrier Protein₁, Kathleen Lobaugh Gavey
Chemistry and Chemical Biology ETDs
The conversion of farnesyl pyrophosphate to squalene by rat liver microsomes was investigated. The enzyme exhibited an apparent maximum velocity at a substrate concentration of 30 μM. No evidence of substrate inhibition was seen at concentrations up to 65 μM. Phosphatases present in the microsomes or in the 105,000 x g supernatant (S105) did not interfere with squalene synthesis under the experimental conditions used.
s105 slightly enhanced the biosynthesis of squalene at the lowest concentrations of microsomal protein studied. The effect was reversed at higher concentrations of microsomes. A 1O-fold increase in the concentration of s105 did not …
Charge Transfer Photochemistry Of Some Chromium (Iii) Complexes, Yohn Sik Kang
Charge Transfer Photochemistry Of Some Chromium (Iii) Complexes, Yohn Sik Kang
Chemistry and Chemical Biology ETDs
The photolyses of a series of chromium(III) complexes Cr(en)3 3+, Cr(den)2 3+, Cr(tn)3 3+, and Cr(pn)3 3+, where en= ethylenediamine, den= diethylenetriamine, tn = trimethylenediamine, and pn = propylenediamine, have been investigated. Experiments were carried out on unbuffered and buffered (pH= 2.00) solutions containing 10^-3 – 10^-2 M chromium(III) complexes at room temperature and 10°C. While purging with argon or oxygen, the irradiation was performed with 184.9-253.7 nm u.v. light, corresponding to the charge transfer bands of the complex.
Chromium(Iii) Tartrates, Gerald Lynn Robbins
Chromium(Iii) Tartrates, Gerald Lynn Robbins
Chemistry and Chemical Biology ETDs
The binuclear tartrate-bridged complexes [Cr2 (tartH)2 (L)2] and Na[Cr2 (tart) (tartH) (L)2]("tart" = C4H2O64-, "tartH" = C4H3O63- and "L"= 1,10-phenanthroline or 2,2'-bipyridyl) have been synthesized where each complex contains either two optically active or two meso bridging ligands. A discussion of the number of isomers and symmetries of these complexes is presented, as well as a complete description of the syntheses of the complexes and their sodium salts. Steric constraints force the octahedral coordination geometry for the dimer containing two …
Reactions Of N-Ethoxycarbonylthioamides With Dinucleophilic Reagents, Babu George
Reactions Of N-Ethoxycarbonylthioamides With Dinucleophilic Reagents, Babu George
Chemistry and Chemical Biology ETDs
When an N-ethoxycarbonylthioamide is treated with dinucleophilic reagents containing a primary or secondary amino group and another nucleophilic group, reaction occurs initially between the amino group of the reagent and the thiocarbonyl of the substrate with elimination of hydrogen sulfide and formation of a carbon, nitrogen double bond. The intermediate thus formed may subsequently cyclize in either of two different manners depending upon the relative positions of the two nucleophilic groups in the reagent. A. If the second nucleophilic group is adjacent to the amino group, or separated from it by one carbon atom, cyclization involves nucleophilic attack at the …
Syntheses Directed Toward The Construction Of 1-Deaza-1-Thialysergic Acid, Nicholas Richards Beller
Syntheses Directed Toward The Construction Of 1-Deaza-1-Thialysergic Acid, Nicholas Richards Beller
Chemistry and Chemical Biology ETDs
With the goal of synthesizing 1-deaza-1-thialysergic acid (31), a series of substituted 2-stilbazole precursors of 31 was prepared.
313, R1=SCH3, R2=H
314, R1=SOCH3, R2=H
315, R1=SO2CH3, R2=H
173, R1=H, R2=COOC2H5
152, R1 =SCH3, R2=COOC2H5
162, R1=SOCH3, R2=COOC2H5
153, R1=SO2CH3, R2=COOC2H5
In connection with the synthesis …