scholarly journals Photoinitiated azo-hydrazo tautomerizm of 1-p- toluenesulphonylazo-2,4,6,8-tetrakis (tert-butyl)phenoxazine

1999 ◽  
Vol 1 (3) ◽  
pp. 161-164
Author(s):  
T. E. Ivakhnenko ◽  
N. I. Makarova ◽  
E. P. Ivakhnenko ◽  
V. I. Minkin ◽  
M. I. Knyazhansky
Keyword(s):  
Photochromic Compound ◽  
Tert Butyl ◽  
Photochromic Transformations ◽  
Photochemical Properties ◽  
Model Structures

A novel photochromic compound with NH-N intramolecular H-bond (1-p-toluenesulphonylazo- 2,4,6,8-tetrakis(tert-butyl)phenoxazine) and the corresponding model structures (1-oxo-2,4,6,8-tetrakis(tertbutyl) phenoxazine, 2,4,5,7-tetrakis (tert-butyl )-1-( veratroylazo ) phenoxazine, 2,4,5,7-tetrakis ( tert-butyl )-Nacetyl- 1-(p-toluenesulphonylazo)phenoxazine) have been synthesized and their spectral and photochemical properties are studied. The photochromic transformations observed are found to be conditioned by ESIPT (as a primary step) followed by E-Z isomerisation about N–N-bond.

2,5,8,11-Tetra-tert-butyl-peri-xanthenoxanthene and its Dication Spectroelectrochemistry and Model Calculations on a Dioxa-22-π-system

1996 ◽  
Vol 51 (3) ◽  
pp. 377-380 ◽  
Author(s):  
Gernot Frenking ◽  
Anton Rieker ◽  
Josef Salbeck ◽  
Bernd Speiser
Keyword(s):  
Ab Initio ◽  
Radical Cation ◽  
Bathochromic Shift ◽  
Quantum Mechanical ◽  
Quantum Mechanical Calculations ◽  
Model Calculations ◽  
Tert Butyl ◽  
Model Structures

Abstract Spectroelectrochemistry of 2,5,8,1 1-tetra-tert-butyl-peri-xanthenoxanthene 1 yields the UV/VIS spectra of the corresponding radical cation 1+ and dication 12+. The bathochromic shift for the dication 12+ relative to 1 and to the isoelectronic hydrocarbon anthanthrene (2) can be understood by quantum mechanical calculations (ab initio, AM1) of model structures.

Synthesis and photochemical properties of 3,6-di-tert-butyl-9H-carbazole derivatives

2015 ◽  
Vol 85 (6) ◽  
pp. 1431-1439 ◽  
Author(s):  
M. S. Gruzdev ◽  
U. V. Chervonova ◽  
E. A. Venediktov ◽  
E. P. Rozhkova ◽  
A. M. Kolker ◽  
...  
Keyword(s):  
Carbazole Derivatives ◽  
Tert Butyl ◽  
Photochemical Properties

Localization of DNA in chromatin using ESI and osmium ammine staining

1990 ◽  
Vol 48 (3) ◽  
pp. 116-117
Author(s):  
C.L. Woodcock ◽  
R.A. Horowitz ◽  
D. P. Bazett-Jones ◽  
A.L. Olins
Keyword(s):  
Spectroscopic Imaging ◽  
Energy Losses ◽  
Electron Spectroscopic Imaging ◽  
Feulgen Reaction ◽  
Specific Location ◽  
Eukaryotic Nucleus ◽  
Chromatin Fibers ◽  
Patiria Miniata ◽  
Model Structures

In the eukaryotic nucleus, DNA is packaged into nucleosomes, and the nucleosome chain folded into ‘30nm’ chromatin fibers. A number of different model structures, each with a specific location of nucleosomal and linker DNA have been proposed for the arrangment of nucleosomes within the fiber. We are exploring two strategies for testing the models by localizing DNA within chromatin: electron spectroscopic imaging (ESI) of phosphorus atoms, and osmium ammine (OSAM) staining, a method based on the DNA-specific Feulgen reaction.Sperm were obtained from Patiria miniata (starfish), fixed in 2% GA in 150mM NaCl, 15mM HEPES pH 8.0, and embedded In Lowiciyl K11M at -55C. For OSAM staining, sections 100nm to 150nm thick were treated as described, and stereo pairs recorded at 40,000x and 100KV using a Philips CM10 TEM. (The new osmium ammine-B stain is available from Polysciences Inc). Uranyl-lead (U-Pb) staining was as described. ESI was carried out on unstained, very thin (<30 nm) beveled sections at 80KV using a Zeiss EM902. Images were recorded at 20,000x and 30,000x with median energy losses of 110eV, 120eV and 160eV, and a window of 20eV.

A Note on Confidence Intervals and Model Specification

Marketing ZFP ◽  
2019 ◽  
Vol 41 (4) ◽  
pp. 33-42
Author(s):  
Thomas Otter
Keyword(s):  
Confidence Intervals ◽  
Generalized Linear Model ◽  
Statistical Information ◽  
Regression Coefficients ◽  
Model Specification ◽  
Model Parameters ◽  
Exploratory Research ◽  
Empirical Calibration ◽  
Credible Intervals ◽  
Model Structures

Empirical research in marketing often is, at least in parts, exploratory. The goal of exploratory research, by definition, extends beyond the empirical calibration of parameters in well established models and includes the empirical assessment of different model specifications. In this context researchers often rely on the statistical information about parameters in a given model to learn about likely model structures. An example is the search for the 'true' set of covariates in a regression model based on confidence intervals of regression coefficients. The purpose of this paper is to illustrate and compare different measures of statistical information about model parameters in the context of a generalized linear model: classical confidence intervals, bootstrapped confidence intervals, and Bayesian posterior credible intervals from a model that adapts its dimensionality as a function of the information in the data. I find that inference from the adaptive Bayesian model dominates that based on classical and bootstrapped intervals in a given model.

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