tic cis-benzenediol was present on both plates, with R, values of 0.21 and 0.24 respectively. Another portion of the thoroughly dried ether extract was treated with Bis (trimethylsily1)trifluoracetamide and trimethylchlorosilane for 30min at 90° C and the trimethylsilyl derivative injected into a Pye 104 chromatograph fitted with a glass column packed with 4% OV 255 on Chromosorb WHP and a flam...

—Competitive global markets oblige the firms to reduce their overall costs while maintaining the same customer service level and this can be achieved just through a precise and efficient management of their supply chain network. The Fixed Charge Transportation Problem (FCTP) which is a more comprehensive type of Transportation Problem (TP) has several applications from different aspects in this...

We propose new cycle-based neighbourhood structures for meta-heuristics aimed at the fixedcharge capacitated multicommodity network design formulation. The neighbourhood defines moves that take explicitly into account the impact on the total design cost of potential modifications to the flow distribution of several commodities simultaneously. Moves are identified through a shortest path-like ne...

Since the 1950s a lot of effort has been devoted into the development of organic conductors. By a substantial degree this has been inspired by W. A. Little’s theoretical analysis of London’s idea that superconductivity might occur in organic macromolecules or polymers [1]. Over time this has resulted in the discovery of several organic metals and superconductors, albeit not with spectacularly h...

In a previous paper we formulated the fixed-charge multiple knapsack problem (FCMKP), and developed an exact algorithm to solve this problem to optimality by combining pegging test and branch-and-bound technique. Although the developed algorithm was quite successful for instances with small number of knapsacks (m), for larger m the problem was hard to solve by this method. Here we present some ...

We study the static screening in a Hubbard-like model using xed-node diiusion Monte Carlo. We nd that the random phase approximation is surprisingly accurate even for metallic systems close to the Mott transition. As a speciic application we discuss the implications of the eecient screening for the supercon-ductivity in the doped Fullerenes. In the Monte Carlo calculations we use trial function...

Quantum yields for charge transport across adenine tracts of increasing length have been measured by monitoring hole transport in synthetic oligonucleotides between photoexcited 2-aminopurine, a fluorescent analogue of adenine, and N(2)-cyclopropyl guanine. Using fluorescence quenching, a measure of hole injection, and hole trapping by the cyclopropyl guanine derivative, we separate the individ...