Central University of Kerala

About: Central University of Kerala is a education organization based out in Kāsaragod, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 556 authors who have published 881 publications receiving 7474 citations.

Evaporation residue cross-section measurements for O 16 + Tl 203 , 205

Abstract: Evaporation residue cross sections for the $^{16}\mathrm{O}+^{203,205}\mathrm{Tl}$ reactions were measured at laboratory beam energies in the range of 82--113 MeV using a gas-filled separator. Transmission efficiency of the separator was estimated using a calibration reaction $^{16}\mathrm{O}+^{197}\mathrm{Au}$ and by simulating the evaporation residues angular distributions. Statistical model calculations were performed for both the measured systems. These calculations overestimate the experimental evaporation residue cross sections. This could be attributed to the presence of noncompound nuclear fission. An estimation of noncompound nuclear fission contribution was carried out. Comparison with neighboring systems shows that a slight change in the entrance channel or the compound nucleus properties makes a large difference in evaporation residue cross sections.

Weak Integer Additive Set-Indexers of Certain Graph Products

Abstract: An integer additive set-indexer is defined as an injective function $f:V(G)\rightarrow 2^{\mathbb{N}_0}$ such that the induced function $g_f:E(G) \rightarrow 2^{\mathbb{N}_0}$ defined by $g_f (uv) = f(u)+ f(v)$ is also injective, where $f(u)+f(v)$ is the sumset of $f(u)$ and $f(v)$ If $g_f(uv)=k \forall uv\in E(G)$, then $f$ is said to be a $k$-uniform integer additive set-indexers An integer additive set-indexer $f$ is said to be a weak integer additive set-indexer if $|g_f(uv)|=max(|f(u)|,|f(v)|) \forall uv\in E(G)$ We have some characteristics of the graphs which admit weak integer additive set-indexers We already have some results on the admissibility of weak integer additive set-indexer by certain graphs and finite graph operations In this paper, we study further characteristics of certain graph products like cartesian product and corona of two weak IASI graphs and their admissibility of weak integer additive set-indexers and provide some useful results on these types of set-indexers

Isolation and Characterization of L-Tryptophan Ammonia Lyase from Rubrivivax benzoatilyticus Strain JA2

Abstract: Ammonia lyase belongs to the family of enzymes that catalyzes the deamination of amino acids. Depending on the relative activity towards the substrates, L-tryptophan ammonia lyase converts L-tryptophan to indole 3-acrylic acid and ammonia. Here, we isolated, purified, and characterized an L-tryptophan ammonia lyase from phototrophic purple non-sulfur bacterium Rubrivivax benzoatilyticus JA2. The isolated L-tryptophan ammonia lyase found to catalyze the reaction of L-tryptophan to produce indole 3-acrylic acid and NH3. The enzyme is a heterotetramer and has the highest affinity to L-tryptophan. The optimum pH and temperature for the enzymatic action were 7.5 and 35°C, respectively and the Km and Vmax were 40.4 ± 23.1 nM and 0.964±0.2046 s(-1), respectively. These results suggest that the isolated enzyme is highly bioactive and could be a new class. Further molecular analyses are required to confirm the novelty of the enzyme.

On a queueing-inventory system with common life time and Markovian lead time process

Abstract: We consider a correlated queueing-inventory system with Markovian arrival of customers, phase type distributed service time and Markovian lead time. Items in each cycle have a common life time. Before the realization of this, a purchased item in a cycle can be cancelled in that cycle itself provided inventory level has not dropped to zero. Common life time and inter-cancellation time follow independent exponential distributions. We exhaustively analyze this system. The special case of customer arrival following a Poisson process and service time exponentially distributed, is shown to yield product form solution, thus extending earlier work to the case of correlated lead time. The inventory replenishment policy is to bring the inventory level to its maximum at the lead time realization. Several numerical illustrations are provided to illustrate the system performance.

Amine functionalized AFI type microporous SAPO-5 materials: preparation, unique method on template extraction, characterization and its catalytic application on epoxide ring opening

Abstract: Microporous AFI type silicoaluminophosphate (SAPO-5) having aminosilane functionality in the framework was prepared by in-situ (direct co-condensation) approach under hydrothermal conditions. The template (structure directing agent) presents within the channels of synthesized aminosilane modified SAPO-5 framework was selectively removed by a unique method using acidic ethanol extraction. Before and after the template extraction, presence of AFI type phase of SAPO-5 was confirmed through powder XRD pattern. The complete removal of template from the channels of framework was confirmed through FT-IR, 13C MAS NMR and N2 sorption studies. The covalent bonding of aminosilane functionality within the organic–inorganic hybrid SAPO-5 framework was evident through 29Si MAS NMR and 13C MAS NMR studies. The final material was utilized for selective synthesis of 1-phenoxy-2-propanol (99%) via propylene oxide ring opening with phenol under solvent free conditions in liquid phase medium.