An admissible minimax estimator of a bounded scale-parameter in a subclass of the exponential family under scale-invariant squared-error loss

A subclass of the scale-parameter exponential family is considered and for the rth power of the scale parameter, which is lower bounded, an admissible minimax estimator under scale-invariant squared-error loss is presented. Also, an admissible minimax estimator of a lower-bounded parameter in the family of transformed chi-square distributions is given. These estimators are the pointwise limits of a sequence of Bayes estimators. Some examples are given.     

Three-dimensional mixed convection flow with variable thermal conductivity and frictional heating

In this article,three-dimensional mixed convection flow over an exponentially stretching sheet is investigated.Energy equation is modelled in the presence of viscous dissipation and variable thermal conductivity.Temperature of the sheet is varying exponentially and is chosen in a form that facilitates the similarity transformations to obtain self-similar equations.Resulting nonlinear ordinary differential equations are solved numerically employing the Runge-Kutta shooting method.In order to check the accuracy of the method,these equations are also solved using bvp4c built-in routine in Matlab.Both solutions are in excellent agreement.The effects of physical parameters on the dimensionless velocity field and temperature are demonstrated through various graphs.The novelty of this analysis is the self-similar solution of the threedimensional boundary layer flow in the presence of mixed convection,viscous dissipation and variable thermal conductivity.     

Measurement of the thermoelectric power of lead sulphide

The thermoelectric power of natural specimens of lead sulphide crystals has been measured between room temperature and 700° K. Specimens which are of then-type remain as such throughout the temperature range. Thep-type specimens, however, show an initial small rise followed by a gradual decrease and a subsequent change of sign ata temperature which, in some specimens, is well defined. Further increase of temperature results in a negative extremum. From this stage onwards there seems to develop a common behaviour for both types of specimens. Some crystals which were initially of thep-type changed over to then-type and remained as such throughout subsequent investigation. Among the crystals one showed a metallic conduction and an extraordinary large thermoelectric power.     

An efficient and one-pot green synthesis of novel 6-oxo-7-aryl-6,7-dihydrochromeno pyrano[2,3-b]pyridine derivatives

A simple and efficient protocol has been developed for the construction of novel 6-oxo-7-aryl-6,7-dihydrochromenopyrano[2,3-b]pyridine derivatives using one-pot, three-component cyclocondensation of 4-hydroxycoumarin, various aromatic aldehydes and 2-aminoprop-1-ene-1,1,3-tricarbonitrile using 10?mol % guanidine hydrochloride as the organocatalyst under solvent-free conditions at 90?°C for the first time. The significant features of this protocol are operational simplicity, provide good to high yields, avoidance of toxic solvents, straightforward work-up, no column chromatographic purification and atom-economy which is considered to be relatively environmentally benign.     

Heat transfer exaggeration and entropy analysis in magneto-hybrid nanofluid flow over a vertical cone: a numerical study

Journal of Thermal Analysis and Calorimetry - Entropy analysis is closely scrutinized for unsteady mixed convection in magneto-hybrid nanofluid (Cu–Fe $$_3$$ O $$_4$$ –water) flow over...     

Synthesis and characterization of a novel silane-based vinylic monomer and its application in the multilayer core-shell latex

A novel monomer methacrylamidophenoxy dimethylsiloxy phenylphthalimide was obtained by a reaction of 4,4′-bis-aminophenoxy dimethylsilane, phthalic anhydride and methacryloyl chloride. Then it has been used in the synthesis of phase-separated polymer latex with a multilayer core-shell morphology by surface cross-linking emulsion polymerization. Poly(butyl acrylate) was used for the seed and the core of the latex, the inner shell was poly(butyl acrylate/styrene) cross-linked with divinylbenzene to avoid phase inversion, and the poly(methyl methacrylate/butyl acrylate/methacrylamidophenoxy dimethylsiloxy phenylphthalimide) was the outer shell. The structural elucidation of monomer was carried out by elemental analysis, FTIR, ¹H NMR, and ¹³C NMR spectroscopic techniques. The morphology and glass transition temperatures of the synthesized product were investigated by transmission electron microscopy and differential scanning calorimetry, respectively. The multilayer core-shell structure was clearly shown in TEM micrographs, and the three-phase separation was confirmed by DSC analysis. The obtained results demonstrated that the average particle size is 81.8, 108 and 132 nm for the core, core-shell and multilayer core-shell particles, which agrees with the TEM micrograph measurement of 75, 103, and 131 nm, respectively.     

Analyzing local and global properties of multigraphs

The local structure of undirected multigraphs under two random multigraph models is analyzed and compared. The first model generates multigraphs by randomly coupling pairs of stubs according to a fixed degree sequence so that edge assignments to vertex pair sites are dependent. The second model is a simplification that ignores the dependency between the edge assignments. It is investigated when this ignorance is justified so that the simplified model can be used as an approximation, thus facilitating the structural analysis of network data with multiple relations and loops. The comparison is based on the local properties of multigraphs given by marginal distribution of edge multiplicities and some local properties that are aggregations of global properties.