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101.
Studies of palladium(II) and platinum(II) binding to well-characterized proteins contribute to understanding the influence of these metals in the environment and body. The well-characterized apoprotein of azurin has a soft-metal binding site that may be exposed to solvent by mutation of a coordinating His-117 residue to glycine (H117G). Palladium(II) and platinum(II) form strong 1:1 adducts with the apo form of H117G azurin. A combination of UV-vis, circular dichroism, and inductively coupled plasma mass spectrometry techniques suggests that the metal binds specifically at His-46 and Cys-112 of the protein. 相似文献
102.
103.
104.
Boulet-Audet M Vollrath F Holland C 《Physical chemistry chemical physics : PCCP》2011,13(9):3979-3984
Whilst rheology is the reference technique to study the mechanical properties of unspun silk, we know little of the structure and the dynamics that generate them. By coupling infrared spectroscopy and shearing forces to study silk fibroin conversion, we are introducing a novel tool to address this gap in our knowledge. Here the silk conversion process has been studied dynamically using polarized attenuated total reflectance Fourier transform infrared spectroscopy whilst applying shear, thus revealing silk protein conformation and molecular orientation in situ. Our results show that the silk conversion process starts with a pre-alignment of the proteins followed by a rapid growth of the β-sheet formation and then a subsequent deceleration of the growth. We propose that this tool will provide further insight into not only silk but any biopolymer solution, opening a new window into biological materials. 相似文献
105.
Samuel S. Holland 《Israel Journal of Mathematics》1987,57(3):365-374
We construct examples of Baer ordered *-fields of the first kind of every dimension 4
n
,n=1,2,…. 相似文献
106.
107.
108.
Polysiloxane Interpenetrating Network Materials as Electronic Device Encapsulants: Synthesis and Properties 总被引:1,自引:0,他引:1
Thermally curable interpenetrating networks employing short and long chain components were successfully prepared via the sol-gel
route. Their mechanical properties were assessed and correlated to their composition and structure. The role of the organic
cross-links was found to be a larger determinant of the mechanical properties than the inorganic network. Their low frequency
dielectric properties were investigated and found to be comparable to those of conventional encapsulation materials. Observed
mass losses at 523 K ranged between 3–5% after 1000 minutes, the suspected mechanism being the development of organic cross-links. 相似文献
109.
E. Cattelain L. Bliecq C. H. Troy P. Fr. Sharp A. Schneck W. Strack und G. Roeder 《Fresenius' Journal of Analytical Chemistry》1931,83(5-6):236-238
Ohne Zusammenfassung 相似文献
110.
William C Troy 《Journal of Mathematical Analysis and Applications》1976,54(3):678-690
We consider the second order nonlinear ordinary differential equations developed by FitzHugh to simplify the fourth order current clamped Hodgkin-Huxley nerve conduction equations. We demonstrate the bifurcation, direction, and stability of a family of small periodic solutions as the current parameter I passes through a critical value. Arguments are given which suggest that this family grows to become a large periodic solution, then shrinks, collapsing onto the steady state as I passes through a second critical value. The usefulness of these results in studying the Hodgkin-Huxley equations is discussed. 相似文献