Preparation and physical properties of nonionic aqueous polyurethane coatings containing different side chain PEGME length

2008 ◽  
Vol 108 (4) ◽  
pp. 2266-2273 ◽  
Author(s):  
Hsiang-Chin Tsai ◽  
Po-Da Hong ◽  
Meng-Shung Yen
2018 ◽  
Author(s):  
N. I. A. M. Hussain ◽  
N. N. Bonnia ◽  
S. N. Syed Ismail ◽  
R. Ramli ◽  
S. N. Surip

2004 ◽  
Vol 82 (2) ◽  
pp. 275-284 ◽  
Author(s):  
Julia Xu ◽  
Mary A.A McRae ◽  
Scott Harron ◽  
Beatrice Rob ◽  
Reuben E Huber

The interactions between Na+ (and K+) and Asp-201 of β-galactosidase were studied. Analysis of the changes in Km and Vmax showed that the Kd for Na+ of wild type β-galactosidase (0.36 ± 0.09 mM) was about 10× lower than for K+ (3.9 ± 0.6 mM). The difference is probably because of the size and other physical properties of the ions and the binding pocket. Decreases of Km as functions of Na+ and K+ for oNPG and pNPG and decreases of the Ki of both shallow and deep mode inhibitors were similar, whereas the Km and Ki of substrates and inhibitors without C6 hydroxyls remained constant. Thus, Na+ and K+ are important for binding galactosyl moieties via the C6 hydroxyl throughout catalysis. Na+ and K+ had lesser effects on the Vmax. The Vmax of pNPF and pNPA (substrates that lack a C6 hydroxyl) did not change upon addition of Na+ or K+, showing that the catalytic effects are also mediated via the C6 hydroxyl. Arrhenius plots indicated that Na+, but not K+, caused k3 (degalactosylation) to increase. Na+ also caused the k2 (galactosylation) with oNPG, but not with pNPG, to increase. In contrast, K+ caused the k2 values with both oNPG and pNPG to increase. Na+ and K+ mainly altered the entropies of activation of k2 and k3 with only small effects on the enthalpies of activation. This strongly suggests that only the positioning of the substrate, transition states, and covalent intermediate are altered by Na+ and K+. Further evidence that positioning is important was that substitution of Asp-201 with a Glu caused the Km and Ki values to increase significantly. In addition, the Kd values for Na+ or K+ were 5 to 8 fold higher. The negative charge of Asp-201 was shown to be vital for Na+ and K+ binding. Large amounts of Na+ or K+ had no effect on the very large Km and Ki values of D201N-β-galactosidase and the Vmax values changed minimally and in a linear rather than hyperbolic way. D201F-β-galactosidase, with a very bulky hydrophobic side chain in place of Asp, essentially obliterated all binding and catalysis.Key words: β-galactosidase, sodium, potassium, binding, aspartic acid.


ChemInform ◽  
2010 ◽  
Vol 30 (24) ◽  
pp. no-no
Author(s):  
Akira Katoh ◽  
Yoshihiro Kitamura ◽  
Hideyuki Fujii ◽  
Yumi Horie ◽  
Tetsuji Satoh ◽  
...  

Polymers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3654
Author(s):  
Rayya A. Al-Balushi ◽  
Ashanul Haque ◽  
Idris J. Al-Busaidi ◽  
Houda Al-Sharji ◽  
Muhammad S. Khan

Metalla-ynes and poly(metalla-ynes) have emerged as unique molecular scaffolds with fascinating structural features and intriguing photo-luminescence (PL) properties. Their rigid-rod conducting backbone with tunable photo-physical properties has generated immense research interests for the design and development of application-oriented functional materials. Introducing a second d- or f-block metal fragment in the main-chain or side-chain of a metalla-yne and poly(metalla-yne) was found to further modulate the underlying features/properties. This review focuses on the photo-physical properties and opto-electronic (O-E) applications of heterometal grafted metalla-ynes and poly(metalla-ynes).


2010 ◽  
Vol 1 (5) ◽  
pp. 747 ◽  
Author(s):  
Hanneke M. L. Lambermont-Thijs ◽  
Lies Bonami ◽  
Filip E. Du Prez ◽  
Richard Hoogenboom

RSC Advances ◽  
2015 ◽  
Vol 5 (27) ◽  
pp. 21310-21315 ◽  
Author(s):  
Hiroyoshi Sugino ◽  
Yasuhito Koyama ◽  
Tamaki Nakano

Poly(xanthon-3-yl methacrylate) having a π-stacked conformation efficiently harvests photo excitation energy for sky blue phosphorescent emission of iridium bis[(4,6-difluorophenyl)pyridinato-N,C2]picolinate (FIrpic) in solution and in film.


RSC Advances ◽  
2016 ◽  
Vol 6 (34) ◽  
pp. 28658-28665 ◽  
Author(s):  
Quoc Viet Hoang ◽  
Chang Eun Song ◽  
In-Nam Kang ◽  
Sang-Jin Moon ◽  
Sang Kyu Lee ◽  
...  

Two low band gap small molecules based on DPP with different terminal side chains were synthesized. They show similar physical properties but different photovoltaic property.


1997 ◽  
Vol 30 (6) ◽  
pp. 1857-1859 ◽  
Author(s):  
Yasutoshi Watanabe ◽  
Takashi Mihara ◽  
Naoyuki Koide

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