Kinetics of radical telomerization of vinylidene fluoride in the presence of CCl3Z chain transfer agents

The kinetics of radical telomerization of VDF at 141 °C, initiated by ditertbutylperoxide, in the presence of three chain transfer agents (CTAs), HCCl₃, CCl₄ and CCl₃Br, are presented. The values of the chain transfer constants were assessed as 35, 0.25 and 0.06 at 141 °C for CCl₃Br, CCl₄ and HCCl₃, respectively. The values of the degree of polymerization (DP_n) were obtained for each CTA and were compared for the same CTA concentration. Hence, CCl₃Br behaved as an efficient CTA towards VDF and usually afforded the monoadduct selectively, but in certain conditions the VDF diadduct can also be produced. In contrast, HCCl₃ was not so efficient since a polymeric structure was identified as the major product.     

Evaluation of sample treatment procedures for the routine identification and determination at nanogram level of O6-monoacetylmorphine in urine by capillary GC and dual NPD-FID

Three methods were evaluated for the determination of O⁶-monoacetylmorphine (6-MAM), the specific metabolite of heroin in human urine, by GC-NPD-FID. The procedure devised for a hydrophobic cation exchange column showed superior performances over the liquid-liquid extraction technique and solid phase extraction with C₁₈. 6-MAM can be analyzed in random urines at the 2 ng/mL concentration with classical equipment for the differentiation between heroin intake and opiates from various origins. The procedure was also applied to enzymatic and acid hydrolyzates of urines. The simultaneous presence of morphine and codeine are useful in the interpretation of results.     

The co-production approach to service: a theoretical background

The paper develops a theoretical background on the co-production approach as an extension of operations management principles, in which co-production function assumes well-defined functional form with the input presence of both firm and customers. The co-production approach not only views a customer as a co-producer, but also conducts strategic trade-offs between a firm and customers in service systems. Moreover, the value and the process of value co-creation are also explored under the co-production approach. The experimental study with a hypothetical service system indicates that the co-production function is feasible under economic and institutional considerations, and the co-production approach generalizes both the firm approach and the customer approach. Furthermore, the co-production approach creates many rich opportunities for future research on service operations management.     

On σ(·, W)-Holomorphic Functions and Theorems of Vitali-Type

The aim of this paper is to give some criterions for holomorphy of F-valued σ(F, W)-holomorphic functions which are bounded on bounded sets in a domain D of Fréchet spaces E (resp. ${\mathbb{C}^n}$ ) where ${W \subset F'}$ defines the topology of Fréchet space F. Base on these results we consider the problem on holomorphic extension of F-valued σ(F, W)-holomorphic functions from non-rare subsets of D and from subsets of D which determines uniform convergence in H(D). As an application of the above, some theorems of Vitali-type for a locally bounded sequence ${\{f_i\}_{i \in \mathbb{N}}}$ of Fréchet-valued holomorphic functions are also proved.     

Function algebras on disks II

This work is a continuation of [7]. In that paper, a sufficient condition was given on a real analytic fmlction g defined near 0 in C so that the algebra generated by z² and g² is dense in the space of continuous functions on D for all disks D close enough to the origin in C. By using the same methods and some ideas taken from the first named author's thesis we deal with the case where g is only of class C¹ near 0.     

Globally solving a nonlinear UAV task assignment problem by stochastic and deterministic optimization approaches

In this paper, we consider a task allocation model that consists of assigning a set of m unmanned aerial vehicles (UAVs) to a set of n tasks in an optimal way. The optimality is quantified by target scores. The mission is to maximize the target score while satisfying capacity constraints of both the UAVs and the tasks. This problem is known to be NP-hard. Existing algorithms are not suitable for the large scale setting. Scalability and robustness are recognized as two main issues. We deal with these issues by two optimization approaches. The first approach is the Cross-Entropy (CE) method, a generic and practical tool of stochastic optimization for solving NP-hard problem. The second one is Branch and Bound algorithm, an efficient classical tool of global deterministic optimization. The numerical results show the efficiency of our approaches, in particular the CE method for very large scale setting.     

A Strong Law for Mixing Random Variables

A sharp almost sure bound is derived for limit points of average sum of weakly dependent random variables, which ensures strong laws of large numbers for and -mixing random variables, without assumptions on rate of tending to zero of and -mixing parameters _n and _n.