Synthesis of hexacyclo[7.4.0.02,8.03,7.06,11]Tridecane-10,13-dione(“homosecohexaprismane-10,13-dione”)

HEXACYCLO[7.4.0.0^2,8.0^3,7.0^6,11]tridecane-10,13-dione (“homosecohexaprismane-10,13-dione”, 8) has been prepared via a six-step sequence that results in homologation of two of the cyclopentane rings in pentacyclo[5.4.0.0^2,6.0^3,10.0^5,9]-undecane-8,11-dione, 1. The structure of 8 has been established unequivocally via single crystal X-ray structural analysis.     

Adhesion through molecular entanglements in polymer interfaces

This paper examines the role of polymer interdiffusion or interpenetration along and across a boundary of two compatible but dissimilar polymers in controlling interfacial adhesion in the interface region (interphase). The effect of interphase adhesion on the mechanical properties as well as the deformation and fracture behavior of sandwich laminates of poly(methylmethacrylate) (PMMA) and poly(vinylidene) fluoride (PVF₂) have been studied. The interphase has been characterized using microscopy (optical, transmission, and scanning electron), dynamic mechanical spectroscopy, and x-ray microanalysis. Conditions of multiple crazing/fracture in the brittle phase (PMMA) and shear yielding in the ductile phase (PVF₂) are discussed. Scanning electron micrographs confirm these deformation modes in PMMA-PVF₂ sandwich composite laminates.     

Bootstrapping a Bayes estimator of a survival function with censored data

The large-sample frequentist property of a frequentist bootstrap for a posterior mean with respect to a Dirichlet prior of the survival function for a randomly censored data is given. The weak convergence of a bootstrap version of the Susarla-Van Ryzin estimator is established on the whole real line. An illustration of the technique and some Monte Carlo studies are also given.     

Bounds onL 1:1 Β (t) in terms of a generalized measure of entropy

In the present paper we define the codes which assign D-alphabet one-one codeword to each outcome of a random variable and the functions which represent possible transformations from one-one codes of size D to suitable codes. By using these functions, we obtain lower bounds on the exponentiated mean codeword length for one-one codes in terms of the generalized entropy of order α and type Β and study the particular cases also.