Solving fuzzy shortest path problems by neural networks

In this paper, we introduce the neural networks for solving fuzzy shortest path problems. The penalization of the neural networks is realized after transforming into crisp shortest path model. The procedure and efficiency of this approach are shown with numerical simulations.     

Order relation between intervals and its application to shortest path problem

It is true that intervals are frequently partially ordered and cannot be compared. Nevertheless, varous definitions for ranking intervals have been proposed. In this paper, we propose a new definition for order relation between intervals by introducing a parameter called “a degree between partial and total order”, and apply it to the shortest path problem with arcs represented as intervals. In order to solve this problem, we modify the Dijkstra's algorithm, and propose a new algorithm obtaining some incomparable interval solutions. Finally, a numerical example is shown.     

The effect of washing and heat treatment on the surface characteristics of fluorocarbon resin-treated polyester

Polyester fabrics and films treated with two fluorocarbon resins were washed and heat treated. Water repellency, surface tension and ESCA measurements were carried out. Changes in the water repellency of the resin-treated polyester fabric caused by washing and heat treatment are related to modification of the chemical composition of the polyester surface.     

Synthesis and surface properties of N-long chain alkyl dihydroxy monoazacrown ethers

A series of N-alkyl dihydroxy monoazacrown ethers (1) was synthesized, and their surface properties were investigated compared to those of N-alkyl monoazacrown ethers (2) and open chain oxyethylenated long chain alkylamines (3). The complexation ability of1 toward alkali metal cations, a distinguished characteristic of crown compounds, was deduced to work even in the aqeuous solution from the values of T_CP, although it is weaker than typical monoazacrown ethers (2). The presence of two hydroxyl groups contributes to the large increase in hydrophilicity of monoazacrown ring and to the large surface excess of the surfactant molecule (1). A small occupation area to the solution surface is noted as a characteristic feature of the title coumpound (1).     

End-functionalized polymers by living cationic polymerization

Summary End-functionalized poly(isobutyl vinyl ether) (2) with a terminal amine, carboxylic acid, or ester group was prepared by quenching the HI/I₂-initiated living polymer ends with ring-substituted anilines (H₂N-C₆H₄-X, p or m; X = NH₂, COOH, COOC₂H₅). The living polymerization of isobutyl vinyl ether and the subsequent end-capping reaction were carried out at –15°C in methylene chloride. The resulting polymers exhibited a narrow molecular weight distribution and carried one terminal function (aniline residue) per chain, according to ¹H NMR structural analysis.     

Preparation and surface active properties of alcohol ethoxylates with an amide oxime terminal group

Amide oxime compounds have become of major interest because they can complex with uranium, gallium and various transition metal ions. In this work surface active amide oximes were prepared to make some functions of the amide oxime group exhibit as molecular aggregates in aqueous media. Amide oximes were obtained from nitriles which were prepared by the cyanoethylation of alcohol ethoxylates with a monodispersed oligo(oxyethylene) group. Surface active properties of these compounds were measured under various conditions and were compared with nonionics of the alcohol ethoxylate type. The pKa₁ values of these amide oximes were about five, and they acted as cationic surfactants under acidic conditions and nonionic ones under neutral and basic conditions. When they served as nonionics, the cloud point, CMC, γ_CMC and foaming properties of surface active amide oximes were similar to other alcohol ethoxylate nonionics.     

Synthetic inorganic ion-exchange materials. XXXIV. Selective separation of lithium from seawater by tin(IV) antimonate cation exchanger

Tin(IV) antimonate (SnSbA) cation exchanger showed an extremely high selectivity for lithium ions compared with other alkali metal ions. The equilibrium distribution coefficients, K_d, were determined at different concentrations of lithium and sodium ions in hydrochloric acid media by batch technique. The K_d values of lithium ions increased with decreasing concentration of lithium ions in the solution, while those of sodium ions were almost independent of sodium concentrations. This behavior can be used to good advantage for the selective separation of lithium at low concentration from sodium ions at high concentration. A successful separation of lithium ions from seawater can be achieved by a column of the SnSbA exchanger in hydrogen ion form. The SnSbA exchanged with lithium and sodium ions can be regenerated using 10 M nitric acid solution as an eluent. Therefore, the SnSbA exchanger can be used repeatedly for the separation of the lithium ions from seawater.