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This paper focuses on establishing the dependence of limiting value of input heat flux for solar assisted thermoelectric generators (TEG) on Angle of Attack (AOA) and wind direction of heat sink of TEG. Current study investigates the limiting input heat flux for TEGs with allowable hot side temperature of 150 °C. A fin block with eight fin configuration and fin length of 60 mm is chosen as heat sink configuration for TEG. Computational Fluid Dynamics (CFD) model is developed and analyzed in this work after validation with published experimental results. CFD model consists of four TEGs encapsulated within a target block and a finned block, placed within a domain which simulates low speed wind tunnel. Air flow in the wind tunnel simulates the outdoor wind conditions. Concentrated solar flux is applied on the face of target block. Effect of ambient air temperature on limiting input heat flux is also studied. Dependence of limiting input heat flux on Angle of Attack (AOA) and wind direction, which arises due to the two axis tracking of Sun by Fresnel lens concentrator has been quantified and it is observed that maximum limiting input heat flux occurs at 30 ° AOA. Maximum limiting heat flux reaches 24,000 W/m2 for 30 ° AOA under 5 m/s wind velocity. It is also observed that maximum input heat flux varies by 42.49% with change in wind velocity from 1 to 5 m/s. Maximum limiting input heat flux occurs at 45 ° for horizontal rotation. Area of square array Fresnel lens concentrator varies by 6.29% for 5 m/s wind velocity when AOA is considered to when AOA is not considered for calculation of Fresnel lens area.

The maximum deflection of a Parabolic Trough Solar Collector (PTSC) absorber tube is a result of the circumferential non-uniformity in temperature distribution and self-weight. This non-uniformity in temperature is a factor of incoming solar flux distribution as well as material property of the absorber tube. The present work focuses on structural analysis of absorber tube used in PTSC and the effects of variations of material. Multiphysics platform, namely thermal-fluid analysis and structural analysis has been made in this regard. The computational investigation has been carried out on Schott PTR70 2008 receiver and Therminol VP1 as the Heat Transfer Fluid (HTF). Evacuated annular space along with specular and non-grey nature of glass cover which is semi-transparent to the input flux has been modeled to obtain better accuracy in results. The materials investigated are steel, copper, aluminum and various laminated composites like bimetallic (Cu-Fe) and tetra-layered laminate (Cu-Al-SiC-Fe), which are subjected to different mass flow rate of HTF at the absorber tube inlet with constant heat flux on the absorber tube outer surface. It is found that the change in the material of the absorber tube has a negligible effect on the amount of heat transferred to the HTF, but it has a significant effect on the bending due to thermal expansion as well as due to self-weight. Steel absorber tube is generally used, but its lower thermal conductivity results in poor circumferential temperature distributions. Copper has better thermal characteristics, but higher self-weight and lower mechanical strength compared to steel. So a combined effect of these properties is utilized in bimetallic tube, which results in a decrease in maximum deflection by 7–15% as compared to steel. As the self-weight of the absorber tube plays a vital role in deflection, therefore a tetra-layered laminate absorber tube having lower weight and improved temperature distribution results in a decrease in maximum deflection by 45–49% as compared to steel.

A pharmaceutical composition and treatment method to reduce the proliferation of cancerous or tumor cells, in which the combined active agents are methylglyoxal, ascorbic acid, creatine and melatonin.

A Bethe ansatz study of Fateev–Zamolodchikov model (FZM) is undertaken for even spin system. One has to solve a coupled system of Bethe ansatz equations (BAE) involving zeroes of two families of transfer matrices. A numerical study on finite size lattices is done for identification of the different classes of solutions (strings) of Bethe ansatz equations that correspond to ferromagnetic ground state and elementary excitations. The free energy for ferromagnetic ground states and dispersion relation for elementary excitations are found.

We study roughening interfaces with a constant slope that become self organized critical by a rule that is similar to that of invasion percolation. The transient and critical dynamical exponents show Galilean invariance. The activity along the interface exhibits non-trivial power law correlations in both space and time. The probability distribution of the activity pattern follows an algebraic relation., 5 journal pages, 4 figures

The classification and completeness of Bethe states is undertaken for the spin 4 Fateev-Zamolodchikov model. This special case is of particular interest as the energy can be derived in a simple closed form even for lattices of arbitrary finite size. The excitation spectrum over the ferromagnetic ground state is also derived.

A Bethe ansatz study of the Fateev-Zamolodchikov model is undertaken for the spin N = 4 system. A complete decoupling of the Bethe equations allows a closed explicit expression for the ground state energy even for a finite lattice. A central charge is extracted by a straightforward expansion.

L-Threonine dehydrogenase, which forms aminoacetone from L-threonine and NAD, has been extensively purified from goat liver. A feedback inhibition of this enzyme has been observed with methylglyoxal. Kinetic data and other experiments indicate that methylglyoxal acts at a site other than the active site of the enzyme. The enzyme contains a single subunit of Mr 89,000. The apparent Km values of the enzyme for L-threonine and NAD were found to be 5.5 and 1 mM, respectively.

An enzyme which catalyzes the reduction of methylglyoxal to lactaldehyde has been isolated and purified from goat liver to apparent homogeneity. NADH was found to be a better substrate than NADPH for methylglyoxal reduction. Stoichiometrically equivalent amounts of lactaldehyde and NAD are formed from methylglyoxal and NADH. Enzyme activity was located only in the soluble supernatant fractions of liver cells. Of the various carbonyl compounds tested, methylglyoxal was found to be the best substrate. The pH optimum of the enzyme was found to be 6.5, and Km for methylglyoxal was 0.4 mM. The molecular weight of the enzyme was found to be 89000 by gel filtration on a Sephadex G-200 column. Electrophoresis on sodium dodecyl sulfate-polyacrylamide gel revealed that the enzyme is composed of two subunits. The enzyme is highly sensitive to sulfhydryl group reagents. The inactivation by p-chloromercuribenzoate could be substantially protected by methylglyoxal in combination with NADH, indicating a possible involvement of one or more sulfhydryl group(s) at the active site of the enzyme.

An enzyme which oxidizes aminoacetone to methylglyoxal has been purified from the particulate fraction of goat liver. Polyamines, such as spermidine and spermine, are also good substrates for this enzyme. The pH optimum for aminoacetone oxidation was found to be 8.2. The apparent Km values of the enzyme for aminoacetone and spermidine were 0.009 and 0.095 mM, respectively. The subunit molecular weight of the enzyme was 93,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The apparent molecular weight of the native enzyme was 186,000 by gel filtration. The enzyme is highly sensitive to carbonyl group reagents. The enzyme is not inhibited by monoamine and diamine oxidase inhibitors.

An enzyme fraction which specifically catalyzes the formation of methylglyoxal from dihydroxyacetone phosphate has been isolated and partially purified from goat liver. The enzyme fraction appears to be substantially free from glyoxalase I, reduced glutathione, and triosephosphate isomerase. Approximately equimolar quantities of methylglyoxal and inorganic phosphate were obtained from dihydroxyacetone phosphate. Formation of methylglyoxal was confirmed by colorimetric and enzymatic estimations as well as by paper chromatography and its spectrum. Glyceraldehyde-3-phosphate, fructose 1,6-bisphosphate, dihydroxyacetone, and glyceraldehyde, failed to act as substrates. The enzyme is inhibited by some phosphorylated compounds and inorganic phosphates.

An enzyme from goat plasma which catalyzes the oxidation of aminoacetone to methylglyoxal has been isolated and purified to apparent homogeneity. This enzyme has been found to be identical with the well known amine oxidase. Several properties of the enzyme have also been described.