scholarly journals Gas permeability versus texture relationship of sediment samples from a research well in the Beaufort-Mackenzie Basin, Northwest Territories

2008 ◽  
Author(s):  
T J Katsube ◽  
S Connell-Madore
Keyword(s):  
Northwest Territories ◽  
Gas Permeability ◽  
Sediment Samples ◽  
Mackenzie Basin ◽  
Relationship Of

scholarly journals Design and application of a microfluidic device for protein crystallization using an evaporation-based crystallization technique

2011 ◽  
Vol 45 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Yong Yu ◽  
Xuan Wang ◽  
Dominik Oberthür ◽  
Arne Meyer ◽  
Markus Perbandt ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Microfluidic Device ◽  
Gas Permeability ◽  
Protein Crystallization ◽  
Microfluidic Devices ◽  
Protein Crystals ◽  
Air Bubbles ◽  
Crystallization System ◽  
Relationship Of

A new crystallization system is described, which makes it possible to use an evaporation-based microfluidic crystallization technique for protein crystallization. The gas and water permeability of the used polydimethylsiloxane (PDMS) material enables evaporation of the protein solution in the microfluidic device. The rates of evaporation are controlled by the relative humidity conditions, which are adjusted in a precise and stable way by using saturated solutions of different reagents. The protein crystals could nucleate and grow under different relative humidity conditions. Using this method, crystal growth could be improved so that approximately 1 mm-sized lysozyme crystals were obtained more successfully than using standard methods. The largest lysozyme crystal obtained reached 1.57 mm in size. The disadvantage of the good gas permeability in PDMS microfluidic devices becomes an advantage for protein crystallization. The radius distributions of aggregrates in the solutions inside the described microfluidic devices were derived fromin situdynamic light scattering measurements. The experiments showed that the environment inside of the microfluidic device is more stable than that of conventional crystallization techniques. However, the morphological results showed that the protein crystals grown in the microfluidic device could lose their morphological stability. Air bubbles in microfluidic devices play an important role in the evaporation progress. A model was constructed to analyze the relationship of the rates of evaporation and the growth of air bubbles to the relative humidity.

Aulacopleurine trilobites from the Llandovery of northwestern Canada

1995 ◽  
Vol 69 (2) ◽  
pp. 326-340 ◽  
Author(s):  
J. M. Adrain ◽  
B. D. E. Chatterton
Keyword(s):  
Northwest Territories ◽  
Early Growth ◽  
Growth Stages ◽  
Mackenzie Mountains ◽  
Relationship Of ◽  
The Relationship

Aulacopleurine trilobites from Llandovery strata of the Whittaker Formation in the central Mackenzie Mountains, Northwest Territories, Canada, include Aulacopleura andersoni n. sp., Aulacopleura? ranfordi n. sp., and Songkania smithi n. sp. The subfamily Aulacopleurinae consists of only the genera Aulacopleura Hawle and Corda, 1847, and Songkania Chang, 1974, characterized by smooth, broad early growth stages and holaspides having expanded frontal and genal areas, covered with dense caecal pits, but usually very subdued tuberculate sculpture. The relationship of Aulacopleura? ranfordi and A.? reedi Přibyl, 1947, to the remainder of species assigned to the genus is ambiguous.

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