Hydrogen Evolution from L-Lactate and L-Malate with the Combination of Lactate Dehydrogenase or Malate Dehydrogenase and Hydrogenase from A. Eutrophus H16

Hydrogen evolution system from L-lactate and L-malate consisting of lactate dehydrogenase or malate dehydrogenase and hydrogenase from cell free extracts of Alcaligenes eutrophus H16 was established. When the solution containing L-lactate, lactate dehydrogenase, NAD and hydrogenase was incubated at 30°C hydrogen evolution was observed. Similarly, the hydrogen evolution was also observed from the L-malate incubated at 30°C.     

Self‐assembly of 2‐pivaloyl‐6‐chloro­pterin

In the title compound, N‐(6‐chloro‐4‐oxo‐3,4‐di­hydro­pteridin‐2‐yl)­‐2,2‐di­methyl­propan­amide, C₁₁H₁₂ClN₅O₂, the rings in the pterin moiety are planar. The amide carbonyl O atom is in syn‐periplanar conformation while the C—N—C—C propanamide linkage is antiperiplanar. The N—H?N and N—H?O intermolecular hydrogen bonds transform the mol­ecules into infinite chains.     

Impact of electron irradiation on particle track etching response in polyallyl diglycol carbonate (PADC)

In the present work, attempts have been made to investigate the modification in particle track etching response of polyallyl diglycol carbonate (PADC) due to impact of 2 MeV electrons. PADC samples pre-irradiated to 1, 10, 20, 40, 60, 80 and 100 Mrad doses of 2 MeV electrons were further exposed to 140 MeV²⁸ Si beam and dose-dependent track registration properties of PADC have been studied. Etch-rate values of the PADC irradiated to 100 Mrad dose electron was found to increase by nearly 4 times that of pristine PADC. The electron irradiation has promoted chain scissioning in PADC, thereby converting the polymer into an easily etchable polymer. Moreover, the etching response and the detection efficiency were found to improve by electron irradiation. Scanning electron microscopy of etched samples further revealed the surface damage in these irradiated PADCs.     

Supernova constraints on neutrino mass and mixing

In this article I review the constraints on neutrino mass and mixing coming from type-II supernovae. The bounds obtained on these parameters from shock reheating, r-process nucleosynthesis and from SN1987A are discussed. Given the current constraints on neutrino mass and mixing the effect of oscillations of neutrinos from a nearby supernova explosion in future detectors will also be discussed.     

k-out-of-n-system with repair:T-policy

We consider a k-out-of-n system with repair underT-policy. Life time of each component is exponentially distributed with parameter λ. Server is called to the system after the elapse ofT time units since his departure after completion of repair of all failed units in the previous cycle or until accumulation ofn — k failed units, whichever occurs first. Service time is assumed to be exponential with rateμ.T is also exponentially distributed with parameter α. System state probabilities in finite time and long run are derived for (i) cold (ii) warm (iii) hot systems. Several characteristics of these systems are obtained. A control problem is also investigated and numerical illustrations are provided. It is proved that the expected profit to the system is concave in α and hence global maximum exists.     

C–H...O,C–H...π and π–π stacking interactions in 3-(2,4-dimethylphenyloxymethyl)-3,4-dihydroisocoumarin

3-(2,4-Dimethylphenyloxymethyl)-3,4-dihydroisocoumarin (C₁₈H₁₈O₃) was prepared by the alkylation of o-lithio N-methyl benzamide with 2-(2,4-dimethylphenoxy)methyl oxirane, followed by alkaline hydrolysis. The compound crystallizes in the orthorhombic space group Pbca with unit cell parameters : a = 8.239(2) Å, b = 14.918(5) Å, c = 24.831(9) Å, Z = 8. The crystal structure was solved by direct methods and refined to R = 0.0514 for 1564 observed reflections. The heterocyclic ring adopts a distorted half-chair conformation. Molecules are connected by π–π interactions between phenyl rings of the isocoumarin nucleus forming dimers. Dimers are connected via C–H...O hydrogen bonds forming chains. Further intermolecular C–H...π hydrogen bonds link the dimer chains to form supramolecular structure.     

Some remarks on a model for internal structure of black holes

Some clarifications about a model for the internal structure of black holes developed in an earlier paper are presented to remove confusion in the interpretation of certain results.     

Ion acoustic solitary waves in a two-electron-temperature plasma

Due to the presence of a relatively cold electron component in a plasma, the ion acoustic solitary wave of a given width has a larger amplitude. When the temperature difference between the two electron components is sufficiently large, the strength of dispersion is reduced to an extent that a solitary solution is no longer possible.     

Beta-branching fraction of117Cd isomers and it branching of117mIn

Using radiochemical and gamma spectrometric technique the branching fractions in the beta decay of¹¹⁷Cd isomers and the internal transition branching of^117mIn have been established. The beta branching fraction of^117gCd^117gIn was obtained as 0.86±0.06 and the value of^117mCd^117gIn was found to be less than 1%. The internal transitin branching and the isomer cross-section ratio were obtained as 0.31±0.02 and 0.197±0.002, respectively. From the measured isomer cross-section ratio the spin cut-off parameter was evaluated, which agreed with the value reported in the literature.     

Molecular reorientation in polypropylene

The molecular reorientation occurring within deformation bands in one-way drawn polypropylene films has been studied by optical microscopy. The deformation bands formed at the yield stress in tension tests on specimens cut at various angles to the initial drawing direction. It is shown that the principal axes of the refractive index ellipsoid in the deformation band coincide with the principal axes of the plastic strain ellipsoid, provided that the strains are referred to the initial isotropic state, i.e., prior to the initial drawing process. This result is similar to the results obtained previously for poly(ethylene terephthalate), but differes somewhat from the results obtained by other workers for poly(vinyl chloride). A possible reason for these differences is discussed.