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- Beckmann Rearrangement (1)
- Cascade Reaction (1)
- Crystal structure (1)
- Cyclotriveratrylene (1)
- Electrophilic Aromatic Substitution (1)
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- Fluorescence (1)
- Gold Nanoparticles (1)
- Heavy Metal Detection (1)
- Hemoglobin (1)
- Lanthanides (1)
- Prokaryotic sucrose synthase (1)
- Pulsed alternating current etching (PACE) (1)
- Quinazoline (1)
- Scanning tunneling microscopy (STM) (1)
- Scapharca inaequivalvis (1)
- Supramolecular Chemistry (1)
- Tandem Sequence (1)
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Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
An Analytical Method For Detecting Toxic Metal Cations Using Cyclotriveratrylene Derivative Capped Gold Nanoparticles, Zachary R. Osner, Richard C. Holz, Daniel P. Becker Ph.D.
An Analytical Method For Detecting Toxic Metal Cations Using Cyclotriveratrylene Derivative Capped Gold Nanoparticles, Zachary R. Osner, Richard C. Holz, Daniel P. Becker Ph.D.
Chemistry: Faculty Publications and Other Works
Cyclotriveratrylene-oxime (CTV-oxime) derivatives that terminate with a dithiolate linker were synthesized enabling the supramolecular scaffold to adhere to gold nanoparticles (AuNPs) with the bowl-shaped cavity of the CTV scaffold exposed for utilization in host–guest chemistry. Exposure of these CTV functionalized AuNPs to varying concentrations of di- and trivalent metal cations resulted in the formation of large CTV-AuNP polymeric clusters and an accompanying a shift in the plasmon resonance. These interactions between the CTV-AuNPs and the metal cations in solution provides proof-of-concept that supramolecular functionalized AuNPs can be used as a simple and straightforward, on-site detection system for toxic metal cations …
Metal-Free Tandem Beckmann–Electrophilic Aromatic Substitution Cascade Affording Diaryl Imines, Ketones, Amines, And Quinazolines, Samuel Sarsah, Marlon R. Lutz Jr., Kailyn Chichi Bobb, Daniel Becker
Metal-Free Tandem Beckmann–Electrophilic Aromatic Substitution Cascade Affording Diaryl Imines, Ketones, Amines, And Quinazolines, Samuel Sarsah, Marlon R. Lutz Jr., Kailyn Chichi Bobb, Daniel Becker
Chemistry: Faculty Publications and Other Works
A cascade reaction sequence involving a Beckmann rearrangement on benzophenone oxime followed by an electrophilic aromatic substitution (EAS) on the intermediate nitrilium ion affords N-phenyl diaryl imines that may then be hydrolyzed to ketones, or reduced to the corresponding amines. Reaction with benzonitrile afforded 2,4-diphenylquinazoline through a Beckmann–Ritter–EAS cascade.
The Crystal Structure Of Nitrosomonas Europaea Sucrose Synthase Reveals Critical Conformational Changes And Insights Into The Sucrose Metabolism In Prokaryotes, Rui Wu, Matías D. Asención Diez, Carlos M. Figueroa, Matías Machtey, Alberto A. Iglesias, Miguel Ballicora, Dali Liu
The Crystal Structure Of Nitrosomonas Europaea Sucrose Synthase Reveals Critical Conformational Changes And Insights Into The Sucrose Metabolism In Prokaryotes, Rui Wu, Matías D. Asención Diez, Carlos M. Figueroa, Matías Machtey, Alberto A. Iglesias, Miguel Ballicora, Dali Liu
Chemistry: Faculty Publications and Other Works
In this paper we report the first crystal structure of a prokaryotic sucrose synthase from the non-photosynthetic bacterium Nitrosomonas europaea. The obtained structure was in an open form, whereas the only other available structure from the plant Arabidopsis thaliana was in a closed conformation. Comparative structural analysis revealed a “hinge-latch” combination, which is critical to transition between the open and closed forms of the enzyme. The N. europaea sucrose synthase shares the same fold as the GT-B family of the retaining glycosyltransferases. In addition, a triad of conserved homologous catalytic residues in the family showed to be functionally critical …
Effects Of Mutations On The Molecular Dynamics Of Oxygen Escape From The Dimeric Hemoglobin Of Scapharca Inaequivalvis, Kevin Trujillo, Tasso Papagiannopoulos, Kenneth W. Olsen
Effects Of Mutations On The Molecular Dynamics Of Oxygen Escape From The Dimeric Hemoglobin Of Scapharca Inaequivalvis, Kevin Trujillo, Tasso Papagiannopoulos, Kenneth W. Olsen
Chemistry: Faculty Publications and Other Works
Like many hemoglobins, the structure of the dimeric hemoglobin from the clam Scapharca inaequivalvis is a “closed bottle” since there is no direct tunnel from the oxygen binding site on the heme to the solvent. The proximal histidine faces the dimer interface, which consists of the E and F helicies. This is significantly different from tetrameric vertebrate hemoglobins and brings the heme groups near the subunit interface. The subunit interface is also characterized by an immobile, hydrogen-bonded network of water molecules. Although there is data which is consistent with the histidine gate pathway for ligand escape, these aspects of the …
Preparation Of Scanning Tunneling Microscopy Tips Using Pulsed Alternating Current Etching, Victor A. Valencia, Avesh A. Thaker, Johnathan Derouin, Damian N. Valencia, Rachael G. Farber, Dana A. Gebel, Daniel Killelea
Preparation Of Scanning Tunneling Microscopy Tips Using Pulsed Alternating Current Etching, Victor A. Valencia, Avesh A. Thaker, Johnathan Derouin, Damian N. Valencia, Rachael G. Farber, Dana A. Gebel, Daniel Killelea
Chemistry: Faculty Publications and Other Works
An electrochemical method using pulsed alternating current etching (PACE) to produce atomically sharp scanning tunneling microscopy (STM) tips is presented. An Arduino Uno microcontroller was used to control the number and duration of the alternating current (AC) pulses, allowing for ready optimization of the procedures for both Pt:lr and W tips using a single apparatus. W tips prepared using constant and pulsed AC power were compared. Tips fashioned using PACE were sharper than those etched with continuous AC power alone. Pt:lr tips were prepared with an initial coarse etching stage using continuous AC power followed by fine etching using PACE. …
Grazing Incidence X-Ray Fluorescence Measurements Of Genesis Sample 30580 For Determination Of Manganese And Nickel Fluences, Martina Schmeling, J. Davidson, P.J. Eng, J.E. Stubbs, A.J.G. Jurewicz, D.S. Burnett
Grazing Incidence X-Ray Fluorescence Measurements Of Genesis Sample 30580 For Determination Of Manganese And Nickel Fluences, Martina Schmeling, J. Davidson, P.J. Eng, J.E. Stubbs, A.J.G. Jurewicz, D.S. Burnett
Chemistry: Faculty Publications and Other Works
Genesis flight sample 30580 was analyzed by grazing incidence X-ray fluorescence spectrometry for subsequent calculation of Mn and Ni fluences.