Atropisomeric Flavoenzyme Models with a Modified Pyrimidine Ring:  Syntheses, Physical Properties, and Stereochemistry in the Reactions with NAD(P)H Analogs

1996 ◽  
Vol 61 (26) ◽  
pp. 9344-9355 ◽  
Author(s):  
Atsuyoshi Ohno ◽  
Jun Kunitomo ◽  
Yasushi Kawai ◽  
Tetsuji Kawamoto ◽  
Masaki Tomishima ◽  
...  
2014 ◽  
Vol 16 (3) ◽  
pp. 1-6 ◽  
Author(s):  
Ewelina Kania ◽  
Jacek Lubczak

AbstractOligoetherols based on pyrimidine ring were obtained upon reaction of barbituric acid with glycidol and alkylene carbonates. These oligoetherols were then used to obtain polyurethane foams in the reaction of oligoetherols with isocyanates and water. The protocol of foam synthesis was optimized by the choice of proper kind of oligoetherol and synthetic composition. The thermal resistance was studied by dynamic and static methods with concomitant monitoring of compressive strength. The polyurethane foams have similar physical properties as the classic ones except their enhanced thermal resistance. They stand long-time heating even at 200°C. Moreover thermal exposition of foams results generally in increase of their compressive strength.


e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Elżbieta Chmiel-Szukiewicz

AbstractNew method of synthesis of polyetherols with 1,3-pyrimidine ring by reactions of 6-aminouracil with ethylene carbonate and propylene oxide was described. The structure of products was analyzed using the IR, 1H-NMR and MALDI-TOF spectroscopies. Some physical properties and thermal stability of polyetherols were investigated. Initial tests on the foaming of polyurethanes obtained from the polyetherols were performed. Some properties of the foams such as apparent density, absorption of water, linear dimensions stability, thermal resistance and compression strength were investigated. Obtained foams show an improved thermal stability.


1976 ◽  
Vol 32 ◽  
pp. 365-377 ◽  
Author(s):  
B. Hauck
Keyword(s):  

The Ap stars are numerous - the photometric systems tool It would be very tedious to review in detail all that which is in the literature concerning the photometry of the Ap stars. In my opinion it is necessary to examine the problem of the photometric properties of the Ap stars by considering first of all the possibility of deriving some physical properties for the Ap stars, or of detecting new ones. My talk today is prepared in this spirit. The classification by means of photoelectric photometric systems is at the present time very well established for many systems, such as UBV, uvbyβ, Vilnius, Geneva and DDO systems. Details and methods of classification can be found in Golay (1974) or in the proceedings of the Albany Colloquium edited by Philip and Hayes (1975).


Author(s):  
Frederick A. Murphy ◽  
Alyne K. Harrison ◽  
Sylvia G. Whitfield

The bullet-shaped viruses are currently classified together on the basis of similarities in virion morphology and physical properties. Biologically and ecologically the member viruses are extremely diverse. In searching for further bases for making comparisons of these agents, the nature of host cell infection, both in vivo and in cultured cells, has been explored by thin-section electron microscopy.


Author(s):  
K.P.D. Lagerlof

Although most materials contain more than one phase, and thus are multiphase materials, the definition of composite materials is commonly used to describe those materials containing more than one phase deliberately added to obtain certain desired physical properties. Composite materials are often classified according to their application, i.e. structural composites and electronic composites, but may also be classified according to the type of compounds making up the composite, i.e. metal/ceramic, ceramic/ceramie and metal/semiconductor composites. For structural composites it is also common to refer to the type of structural reinforcement; whisker-reinforced, fiber-reinforced, or particulate reinforced composites [1-4].For all types of composite materials, it is of fundamental importance to understand the relationship between the microstructure and the observed physical properties, and it is therefore vital to properly characterize the microstructure. The interfaces separating the different phases comprising the composite are of particular interest to understand. In structural composites the interface is often the weakest part, where fracture will nucleate, and in electronic composites structural defects at or near the interface will affect the critical electronic properties.


Author(s):  
James Mark ◽  
Kia Ngai ◽  
William Graessley ◽  
Leo Mandelkern ◽  
Edward Samulski ◽  
...  
Keyword(s):  

1982 ◽  
Vol 85 (1) ◽  
pp. 257-263 ◽  
Author(s):  
A. Graja ◽  
M. Przybylski ◽  
B. Butka ◽  
R. Swietlik

2013 ◽  
Author(s):  
Kristina F. Pattison ◽  
Jennifer R. Laude ◽  
Thomas R. Zentall
Keyword(s):  

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