Dynamic Bivariate Mortality Modelling

The dependence structure of the life statuses plays an important role in the valuation of life insurance products involving multiple lives. Although the mortality of individuals is well studied in the literature, their dependence remains a challenging field. In this paper, the main objective is to introduce a new approach for analyzing the mortality dependence between two individuals in a couple. It is intended to describe in a dynamic framework the joint mortality of married couples in terms of marginal mortality rates. The proposed framework is general and aims to capture, by adjusting some parametric form, the desired effect such as the “broken-heart syndrome”. To this end, we use a well-suited multiplicative decomposition, which will serve as a building block for the framework to relate the dependence structure and the marginals, and we make the link with existing practice of affine mortality models. Finally, given that the framework is general, we propose some illustrative examples and show how the underlying model captures the main stylized facts of bivariate mortality dynamics.

     

Effect of simultaneous application of chaotic laminar flow of nanofluid and non-uniform magnetic field on the entropy generation and energetic/exergetic efficiency

Journal of Thermal Analysis and Calorimetry - This work aims to characterize the heat exchange system efficiency and entropy generation of nanofluid forced convection flow with chaotic...     

The Transition States for CO2 Capture by Substituted Ethanolamines

Quantum chemical studies are used to understand the electronic and steric effects on the mechanisms of the reaction of substituted ethanolamines with CO₂. SCS‐MP2/6‐311+G(2d,2p) calculations are used to obtain the activation energy barriers and reaction energies for both the carbamate and bicarbonate formation. Implicit solvent effects are included with the universal solvation model SMD. Carbamate formation is more favorable than bicarbonate formation for monoethanolamine (MEA) both kinetically and thermodynamically. Increase of the steric hindrance on the C atoms around the N atom in substituted ethanolamines favors bicarbonate formation over carbamate formation with lower activation barriers and thereby higher reaction rates. In contrast, substitution by an N‐methyl or N‐ethyl group on MEA leads to a lower activation barrier for both carbamate formation and bicarbonate formation. As a result, higher reaction rates are expected as compared to MEA, and therefore these compounds have significant potential as industrial CO₂ capturing solvents.     

Synthesis and anticancer activity of some novel diethyl {(chromonyl/pyrazolyl) [(4-oxo-2-phenyl-quinazolin-3(4H)-yl)amino]methyl}phosphonates

Abstract

The synthesis of some novel chromonyl and pyrazolyl α-aminophosphonates containing a quinazolinone ring was carried out by applying Pudovik and Kabachnik-Fields reactions under solvent- and catalyst-free conditions. The anticancer activities of these compounds were evaluated against five cancer cell lines. 3-{[(3-Phenyl/1,3-diphenyl-1H-pyrazol-4-yl)methylidene]amino}-2-phenyl-quinazolin-4(3H)-ones (3d,e) and diethyl {[3-phenyl/1,3-diphenyl-1H-pyrazol-4-yl][(4-oxo-2-phenyl-quinazolin-3(4H) yl)amino] methyl}phosphonates (4d,e) displayed the potent anticancer activities against HCT116, MCF-7 and HepG2 cell lines in comparison with the standard drug.     

Negative capacitance of ZnGa2Se4/Si nano-heterojunction diode

The negative capacitance (NC) behavior in p-ZnGa₂Se₄/n-Si nano-crystalline HJD was characterized by admittance-voltage method. The C–V, G–V and R _s –V for the studied diode were analysed in the frequency range of 1–5 MHz and in the temperature range of 303–423 K. The capacitance and conductance plots were interpreted in terms of interface states and series resistance. The C–V and G/ω–V plots exhibit a pounced peak due to the interface states and the series resistance effects. The negative capacitance behavior in the studied diode can be explained in terms of the transient currents.     

Synthesis of novel 3-phenyl-2-oxido/sulfido-1,3,4,2-benzoxadiazaphosphepines

An efficient and facile synthetic approach towards a series of novel 3-phenyl-2-oxido/sulfido-2,3-dihydro-1,3,4,2-benzoxadiazaphosphepines 2–7 was described. The method depended on the cyclocondensation of equimolar ratios of salicylaldehyde phenylhydrazone (1) with different examples of phosphorus halides and phosphorus sulfides in toluene containing triethylamine as a catalyst. In the same manner, the fusion of salicylaldehyde phenylhydrazone (1) with triethyl phosphate in the presence of DBU afforded the 2-ethoxy-1,3,4,2-benzoxa-diazaphosphepine 8, while a fusion of compound 1 with diethyl phosphite and tris(2-chloroethyl)phosphite led to the formation of new examples of 1,2-benzoxaphospholes 9 and 10, respectively. Interestingly, the reaction of compound 1 with diethyl ethoxycarbonyl phosphonate in ethanol containing DBU as a catalyst furnished the chromeno[3,4-d][1,2,3]diazaphosphole derivative 12 as a regioselective product.     

New synthesis and reactivity of 3‐bromoacetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one with binucleophilic amines

3‐(Bromoacetyl)‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one was synthesized by the reaction of dehydroacetic acid (DHAA) with bromine in glacial acetic acid. Novel heterocyclic products were synthesized from the reaction of bromo‐DHAA with alkanediamines, phenylhydrazines, ortho‐phenylenediamines, and ortho‐aminobenzenethiol. The obtained new products 3‐(2‐N‐substituted‐acetyl)‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐ones, 4‐hydroxy‐3‐[1‐hydroxy‐2‐(2‐phenylhydrazinyl)vinyl]‐6‐methyl‐2H‐pyran‐2‐one, 1‐(2,4‐dinitrophenyl)‐7‐methyl‐2,3‐dihydro‐1H‐pyrano[4,3‐c]pyridazine‐4,5‐dione, 3‐(3,4‐dihydroquinoxalin‐2‐yl)‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one/3‐(3,4‐dihydroquinoxalin‐2‐yl)‐6‐methyl‐2H‐pyran‐2,4(3H)‐dione, 6‐methyl‐3‐(3,4‐dihydroquinoxalin‐2‐yl)‐2H‐pyran‐2,4(3H)‐dione, and (E)‐3‐(2H‐benzo[b][1,4]thiazin‐3(4H)‐ylidene)‐6‐methyl‐2H‐pyran‐2,4(3H)‐dione were fully characterized by IR, ¹H and ¹³C NMR, and mass spectra. J. Heterocyclic Chem., 2011.     

Sodium calcium orthovanadate,NaCa4(VO4)3

Single crystals of sodium tetra­calcium trivanadium dodeca­oxide were prepared by melting a powder sample of NaCa₄(VO₄)₃ at 1673 K, followed by slow cooling to room temperature. The compound crystallizes in the Pnma space group and is isostructural with the mineral silicocarnotite, Ca₅(PO₄)₂SiO₄. The structure is composed of isolated VO₄ tetra­hedra linked by sodium and calcium cations disordered over eight‐ and seven‐coordinated sites.