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Dimethyl (±)-(1s*,2r*,3s*)-[3-Phenyl-1-(N-Phenylcarbamoyloxy)-2, 3-Epoxypropyl]-Phosphonate, T. Boehlow, A. De La Cruz, N. P. Rath, C. D. Spilling Dec 1997

Dimethyl (±)-(1s*,2r*,3s*)-[3-Phenyl-1-(N-Phenylcarbamoyloxy)-2, 3-Epoxypropyl]-Phosphonate, T. Boehlow, A. De La Cruz, N. P. Rath, C. D. Spilling

Christopher Spilling

The crystal structure of the racemic title compound, C18H20NO6P, m.p. 428-431 K, has been determined by X-ray diffraction. The title compound consists of a tetrahedral P atom bonded to two methoxy groups, and an alkyl chain. The alkyl chain was substituted at position 1 with a carbamate and with an epoxide at positions 2 and 3. The relative configuration of the 1-carbamate and 2,3-epoxide substituents was confirmed as anti (1S,2R,3S). The crystal structure contains an enantiomeric pair with two intermolecular hydrogen bonds in a 14-membered ring. The hydrogen bonds are formed between the P=O of one enantiomer and the N-H …


Dimethyl (±)-(1s*,2r*,3s*)-[3-Phenyl-1-(N-Phenylcarbamoyloxy)-2, 3-Epoxypropyl]-Phosphonate, T. Boehlow, A. De La Cruz, Nigam P. Rath, C. D. Spilling Dec 1997

Dimethyl (±)-(1s*,2r*,3s*)-[3-Phenyl-1-(N-Phenylcarbamoyloxy)-2, 3-Epoxypropyl]-Phosphonate, T. Boehlow, A. De La Cruz, Nigam P. Rath, C. D. Spilling

Nigam Rath

The crystal structure of the racemic title compound, C18H20NO6P, m.p. 428-431 K, has been determined by X-ray diffraction. The title compound consists of a tetrahedral P atom bonded to two methoxy groups, and an alkyl chain. The alkyl chain was substituted at position 1 with a carbamate and with an epoxide at positions 2 and 3. The relative configuration of the 1-carbamate and 2,3-epoxide substituents was confirmed as anti (1S,2R,3S). The crystal structure contains an enantiomeric pair with two intermolecular hydrogen bonds in a 14-membered ring. The hydrogen bonds are formed between the P=O of one enantiomer and the N-H …


34. Shunsuke Murahashi, Otto Vogl, Mikiharu Kamachi, Koichi Hatada Dec 1997

34. Shunsuke Murahashi, Otto Vogl, Mikiharu Kamachi, Koichi Hatada

Otto Vogl

No abstract provided.


Icris '96: Controlled Organization And Molecular Dynamics Of Polymers, Uji, Kyoto, Japan, Otto Vogl, Masaki Tsuji Dec 1997

Icris '96: Controlled Organization And Molecular Dynamics Of Polymers, Uji, Kyoto, Japan, Otto Vogl, Masaki Tsuji

Otto Vogl

No abstract provided.


Japan-Us Seminar: Macromolecular Architecture And Engineering, Otto Vogl, Shin-Ichiro Shoda Nov 1997

Japan-Us Seminar: Macromolecular Architecture And Engineering, Otto Vogl, Shin-Ichiro Shoda

Otto Vogl

No abstract provided.


35. Shigeharu Onogi, Otto Vogl, Masaoki Takahashi, Toshiro Masuda Nov 1997

35. Shigeharu Onogi, Otto Vogl, Masaoki Takahashi, Toshiro Masuda

Otto Vogl

No abstract provided.


36. Qian Renyuan, Otto Vogl, Wu Meiyan Oct 1997

36. Qian Renyuan, Otto Vogl, Wu Meiyan

Otto Vogl

No abstract provided.


Voltammetric Studies Of Metallofullerenes, Mark Anderson Sep 1997

Voltammetric Studies Of Metallofullerenes, Mark Anderson

Mark R. Anderson

No abstract is available at this time.


Voltammetry And Spectroelectrochemistry Of Metallofullerenes, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson Sep 1997

Voltammetry And Spectroelectrochemistry Of Metallofullerenes, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson

Mark R. Anderson

No abstract is currently available.


Segregation Of Bismuth To Triple Junctions In Copper, K.-M. Yin, Alexander H. King, T.E. Hsieh, F.-R. Chen, J.J. Kai, L. Chang Sep 1997

Segregation Of Bismuth To Triple Junctions In Copper, K.-M. Yin, Alexander H. King, T.E. Hsieh, F.-R. Chen, J.J. Kai, L. Chang

Alexander H. King

Bismuth segregation in copper has been studied using energy-dispersive X-ray spectrometry (EDX) in a JEOL 2010F transmission electron microscope. In addition to the expected solute enrichment at grain boundaries, we have observed extremely high concentrations of bismuth at certain triple junctions, with significantly greater enrichment factors than in the adjacent grain boundaries. It is shown here that the triple junction segregation is a function of the parameters of the grain boundaries at the triple line, and existence of this type of segregation implies that the affected triple junctions embody excess free energy. At least one of the observed triple junctions …


37. Masao Horio 1905-1996, Otto Vogl, Masahide Yamamoto Sep 1997

37. Masao Horio 1905-1996, Otto Vogl, Masahide Yamamoto

Otto Vogl

No abstract provided.


38. Hiromichi Kawai, Otto Vogl, Takeji Hashimoto Aug 1997

38. Hiromichi Kawai, Otto Vogl, Takeji Hashimoto

Otto Vogl

No abstract provided.


39. Shu Kambara, Otto Vogl, Seiichi Nakahama Jul 1997

39. Shu Kambara, Otto Vogl, Seiichi Nakahama

Otto Vogl

No abstract provided.


Synthesis Of [15n,15n‘]-N,N,N‘,N‘-Tetramethyl- Ethylenediamine And Its Use In Solvation Studies Of [6li]-N-Butyllithium., Delia Waldmüller, Barbara Kotsatos, Michael Nichols, Paul Williard Jun 1997

Synthesis Of [15n,15n‘]-N,N,N‘,N‘-Tetramethyl- Ethylenediamine And Its Use In Solvation Studies Of [6li]-N-Butyllithium., Delia Waldmüller, Barbara Kotsatos, Michael Nichols, Paul Williard

Michael A Nichols

No abstract provided.


40. Otto Vogl, Joseph C. Salamone Jun 1997

40. Otto Vogl, Joseph C. Salamone

Otto Vogl

No abstract provided.


The Voltammetry Of Mn@C82, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson May 1997

The Voltammetry Of Mn@C82, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson

Mark R. Anderson

No abstract is currently available.


41. Akio Nakajima, 1921-1997, Otto Vogl, Toshio Hayashi May 1997

41. Akio Nakajima, 1921-1997, Otto Vogl, Toshio Hayashi

Otto Vogl

No abstract provided.


Ac-Mode Atomic Force Microscope Imaging In Air And Solutions With A Thermally Driven Bimetallic Cantilever Probe, Andrew C. Hillier, Allen J. Bard Apr 1997

Ac-Mode Atomic Force Microscope Imaging In Air And Solutions With A Thermally Driven Bimetallic Cantilever Probe, Andrew C. Hillier, Allen J. Bard

Andrew C. Hillier

An ac imaging mode for atomic force microscopy ~AFM! has been developed that employs a thermally driven bimetallic cantilever to sense surface topography. Oscillations are induced in a composite cantilever, comprising a Si3N4 layer and Au overcoat, by local heating with a resistive wire heater placed in close proximity to the cantilever. Cantilever bending occurs upon heating due to the difference in thermal expansion coefficients of the Si3N4 and Au layers. The magnitude of this bending is a function of the heat input, the cantilever geometry, the frequency of the excitation, and the thermal properties of the surrounding medium. A …


42. Kenichi Fukui, Otto Vogl, Tetsuki Yamaoka Apr 1997

42. Kenichi Fukui, Otto Vogl, Tetsuki Yamaoka

Otto Vogl

No abstract provided.


43. Karl Kratzl, Otto Vogl Mar 1997

43. Karl Kratzl, Otto Vogl

Otto Vogl

No abstract provided.


44. Vogl Receives Honorary Doctoral Degree From Osaka University, Koichi Hatada Feb 1997

44. Vogl Receives Honorary Doctoral Degree From Osaka University, Koichi Hatada

Otto Vogl

No abstract provided.


The Voltammetry Of Sc3@C82, Mark Anderson, Harry Dorn, Paul Burbank, Steven Stevenson, James Gibson Jan 1997

The Voltammetry Of Sc3@C82, Mark Anderson, Harry Dorn, Paul Burbank, Steven Stevenson, James Gibson

Mark R. Anderson

Many endohedral metallofullerenes have a C82 cage surrounding the metals, even though the normal arc-vaporization method of fullerene preparation does not generate C82 in significant abundance.1-10Manolopous et al.11-13attribute the low abundance of empty-cage C82 to the unfavorable electron configuration of this species. Consequently, the prevalence of C82 in metallofullerenes may be the result of an electron transfer from the encapsulated metal atoms to the fullerene cage.10-13 The extent of this charge transfer also contributes to the properties (e.g. catalytic, superconductive, nonlinear optical, and ferromagnetic) that are attributed to the endohedral metallofullerenes.14,15Because of the importance of the charge transfer reaction, characterization …


Pseudo-Steady States In The Model Of The Bray-Liebhafsky Oscillatory Reaction, Zeljko D. Cupic Jan 1997

Pseudo-Steady States In The Model Of The Bray-Liebhafsky Oscillatory Reaction, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.


The S0 State Of The Oxygen-Evolving Complex In Photosystem Ii Is Paramagnetic:  Detection Of An Epr Multiline Signal, Johannes Messinger, John H. Robblee, Edward Yu, Kenneth Sauer, Vittal K. Yachandra, Melvin P. Klein Jan 1997

The S0 State Of The Oxygen-Evolving Complex In Photosystem Ii Is Paramagnetic:  Detection Of An Epr Multiline Signal, Johannes Messinger, John H. Robblee, Edward Yu, Kenneth Sauer, Vittal K. Yachandra, Melvin P. Klein

Edward Yu

The photosynthetic oxidation of water to molecular oxygen is energetically driven by light-induced charge separations in the reaction center of photosystem II (PS II). The reaction is catalyzed by a tetranuclear manganese cluster contained in the oxygen-evolving complex (OEC). The OEC cycles through five different redox states termed S0 to S4, with S1 being the darkstable state. Oxygen is released during the S4 f S0 transition.1 The removal of one electron from the OEC on each S state transition leads to the idea that alternate S states should be paramagnetic because of their odd-electron number. The multiline EPR signal, which …


Photothermal Lens Spectrometry Of Homogeneous Fluids With Incoherent White‐Light Excitationusing A Cylindrical Sample Cell, Agnes Chartier, Stephen E. Bialkowski Jan 1997

Photothermal Lens Spectrometry Of Homogeneous Fluids With Incoherent White‐Light Excitationusing A Cylindrical Sample Cell, Agnes Chartier, Stephen E. Bialkowski

Stephen E. Bialkowski

A model for photothermal lens signal generation in a cylindrical sample cell under constant irradiance excitation is described and tested. The model is developed with and without the assumption that the sample cell does not change temperature over the irradiation time. In both cases, the photothermal lens is predicted to be parabolic in form with a strength that is independent of sample cell radius. The predicted irradiance independence suggests that incoherent illumination can be used to perform photothermal lens spectroscopy in low-volume cells. Experimental evidence is obtained using a Xe arc lamp to perform photothermal lens spectroscopy in a 6 …


Diffraction Effects In Single‐ And Two‐Laser Photothermal Lens Spectroscopy, Stephen E. Bialkowski, Agnes Chartier Jan 1997

Diffraction Effects In Single‐ And Two‐Laser Photothermal Lens Spectroscopy, Stephen E. Bialkowski, Agnes Chartier

Stephen E. Bialkowski

A simple method for calculating the effects of optical geometry on photothermal lens signals is shown. This method is based on calculating cumulative electric-field phase shifts produced by a series of Gaussian refractive-index perturbations produced by the photothermal effect. Theoretical results are found for both pulsed-laser and continuous Gaussian laser excitation sources and both single- and two-laser apparatuses commonly employed in photothermal lens spectroscopy. The effects of apparatus geometry on the resulting signal are shown. Analytical time-dependent signal results are found for small signals. Analytical pump–probe focus geometry results allow direct optimization for certain conditions. The calculations indicate that the …


Complexes Between Nascent Polypeptides And Their Molecular Chaperones In The Cytosol Of Mammalian Cells, Daryl K. Eggers, W. J. Welch, W. J. Hansen Jan 1997

Complexes Between Nascent Polypeptides And Their Molecular Chaperones In The Cytosol Of Mammalian Cells, Daryl K. Eggers, W. J. Welch, W. J. Hansen

Daryl K. Eggers

Folding of newly synthesized proteins in vivo is believed to be facilitated by the cooperative interaction of a defined group of proteins known as molecular chaperones. We investigated the direct interaction of chaperones with nascent polypeptides in the cytosol of mammalian cells by multiple methods. A new approach using a polyclonal antibody to puromycin allowed us to tag and capture a population of truncated nascent polypeptides with no bias as to the identity of the bound chaperones. In addition, antibodies that recognize the cytosolic chaperones hsp70, CCT (TRiC), hsp40, p48 (Hip), and hsp90 were compared on the basis of their …


A Niobium(V) Complex With Mixed O,S-Donor Ligands. Synthesis, Structure And Properties Of The Anion Tris(2-Mercapto-4-Methylphenolato)Niobate(V), Paul Challen, Diane Peapus, Karen Magnes Dec 1996

A Niobium(V) Complex With Mixed O,S-Donor Ligands. Synthesis, Structure And Properties Of The Anion Tris(2-Mercapto-4-Methylphenolato)Niobate(V), Paul Challen, Diane Peapus, Karen Magnes

Paul R. Challen

Reaction of Nb(OEt)5 with 2-mercapto-4-methylphenol (mmpH2) in the presence of triethylamine gave the mononuclear tris complex (Et3NH)[Nb(mmp)3] which was structurally characterized. The coordination geometry around the niobium is between octahedral and trigonal prismatic, with a twist angle of 41.5°. The mercaptophenolate ligands are arranged around the metal in a “propeller” fashion. (Et3NH)[Nb(mmp)3] was characterized by IR, 1H NMR and UV-vis spectroscopies, and cyclic voltammetry. A reversible reduction wave found at −1.03 V is for reduction to the NbIV complex.


Voltammetric Studies Of Mn@C82, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson Dec 1996

Voltammetric Studies Of Mn@C82, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson

Mark R. Anderson

The voltammetry for a series of related endohedral metallofullerenes is reported. It is found that as additional metal atoms are inserted into the fullerene cage, the first reduction of the metallofullerenes shifts to more negative potentials. This is consistent with more charge being transferred to the fullerene cage from the additional metal atom; however, the magnitude of the shift is much smaller than expected.


Direct Measurement Of Diffuse Double-Layer Forces At The Semiconductor/Electrolyte Interface Using An Atomic Force Microscope, Kai Hu, Fu-Ren F. Fan, Allen J. Bard, Andrew C. Hillier Dec 1996

Direct Measurement Of Diffuse Double-Layer Forces At The Semiconductor/Electrolyte Interface Using An Atomic Force Microscope, Kai Hu, Fu-Ren F. Fan, Allen J. Bard, Andrew C. Hillier

Andrew C. Hillier

The forces between a silica probe and an n-type TiO2 single-crystal electrode were measured using an atomic force microscope in an aqueous electrolyte solution. These interactions were a strong function of the solution pH, the presence of specifically adsorbed anions, and the TiO2 electrode potential. For a series of pH values, a strong electrostatic repulsion was seen at high pH and decreased as the pH was reduced. At pH values below 5.5, the interaction became attractive. A series of force measurements between SiO2 and n-type TiO2 showed a repulsive interaction when TiO2 was held at negative electrode potentials, which transformed …