A. Kaul

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This is a study on the recovery and recycling of copolymer in aqueous two-phase systems containing random copolymers of ethylene oxide (EO) and propylene oxide (PO). The random copolymers separate from water solution when heated above the lower critical solution temperature (LCST). The primary phase systems were composed of EOPO copolymer and hydroxypropyl(More)
Macroscopic resonant tunneling between the two lowest lying states of a bistable rf SQUID is used to characterize noise in a flux qubit. Measurements of the incoherent decay rate as a function of flux bias revealed a Gaussian-shaped profile that is not peaked at the resonance point but is shifted to a bias at which the initial well is higher than the target(More)
Patch pipette, (b) oxide-semiconductor field-effect transistor (OSFET). Abstract-A CMOS sensor array for extracellular, high density imaging of electrical activity of living neural networks is presented. The chip is fabricated in an extended 0.5 µm CMOS technology, and provides 128 x 128 pixels with a pitch of 7.8 µm, full frame rate is 2000 frames per(More)
Foam separation may have potential for protein recovery. However, for foam separation to be a viable protein recovery technique it is important to demonstrate, not only that high enrichments and recoveries can be achieved for single proteins, but also that high enrichments and recoveries, together with selectivity of partition, can be achieved for recovery(More)
Two separation techniques, foam separation and colloidal gas aphrons (CGAs), both of which are based on gas-liquid dispersions, are compared as potential applications for protein recovery in downstream processing. The potential advantages of each method are described and the concentration and selectivity achieved with each method, for a range of proteins is(More)
We present a simple and accurate numerical method for the determination of the complex propagation constants of metal-clad graded-index planar waveguides with arbitrary refractive-index profiles. Numerical results for practically important profiles such as exponential and Gaussian are presented and compared with the homogeneous core waveguides. The analysis(More)
The partition of the protein thaumatin in the presence of Escherichia coli contaminant proteins has been studied. Extraction of thaumatin was followed by back-extraction of the product into a new phosphate phase and also back extraction combined with recycle of the top polyethylene glycol (PEG) phase. When partitioned in the absence or presence of insoluble(More)
Foam separation is known to have potential for separation of biological molecules with a range of surface activities. A statistical study (factorial design) was carried out to establish the optimum operating conditions for the continuous foam separation of beta-casein. Maximum values of enrichment of beta-casein into the foam phase were found for low levels(More)