On the Ricci dark energy model

We study the Ricci dark energy model (RDE) which was introduced as an alternative to the holographic dark energy model. We point out that an accelerating phase of the RDE is that of a constant dark energy model. This implies that the RDE is not a new model of explaining the present accelerating universe.     

NMR Study of the Hydrogen Bonding of Sterically Hindered Phenols with Alicyclic Ethers and Pyridine

In a preliminary report¹ it was shown that the hydrogen-bond chemical shift, δ_AB, correlates with the change in enthalpy, δH, in the interaction of chloroform with a series of closely related oxygen and nitrogen bases. In this communication, we report the hydrogen bonding parameters for the interaction in cyclohexane medium between 2,4,6-tri-t-butylphenol and tetrahydrofuran, tetrahydropyran and pyridine, and between 2,6-di-1-adamantyl-4-t-butylphenol and pyridine. There is correlation between the δ_AB and δ_AE for the same proton donor (2,4,6-tri-t-butylphenol) and the closely related alicyclic bases, and for the same base (pyridine) and the two closely related sterically hindered phenols. The temperature dependence of the δ_AB in these systems is also reported.     

A functional equation arising from ranked additive and separable utility

All strictly monotonic solutions of a general functional equation are determined. In a particular case, which plays an essential role in the axiomatization of rank-dependent expected utility, all nonnegative solutions are obtained without any regularity conditions. An unexpected possibility of reduction to convexity makes the present proof possible.

     

Rheological properties of UHMWPE/iPP blends

The effects of isotactic polypropylene (PP) on the rheological properties of ultra high molecular weight polyethylene (UHMWPE) have been measured in a broad range of composition (0, 5, 15, 30 wt% PP) at various temperatures (110, 130, and 150°C) and a specific gel concentration of 6 wt%. The result showed that the viscosity of the UHMWPE significantly decreased with the addition and increasing amount of PP. Regardless of temperature, the viscosity function followed the power‐law behavior. Copyright © 2009 John Wiley & Sons, Ltd.     

S‐[4‐(Tri­methyl­ammonio)­phenyl]thio­sulfate,an aromatic organic thio­sulfate

The title compound, C₉H₁₃NO₃S₂, exists as a zwitterion with crystallographic mirror symmetry. The central S atom of the S₂O₃ group adopts a slightly distorted tetrahedral coordination geometry. The S—S bond length is 2.1137 (7) Å, while the S—O bond lengths are in the range 1.4417 (12)–1.457 (2) Å. The zwitterions in the crystal adopt a head‐to‐tail arrangement, which leads to the formation of a three‐dimensional network through C—H⋯O hydrogen bonds.     

A survey of scheduling problems with setup times or costs

The first comprehensive survey paper on scheduling problems with separate setup times or costs was conducted by [Allahverdi, A., Gupta, J.N.D., Aldowaisan, T., 1999. A review of scheduling research involving setup considerations. OMEGA The International Journal of Management Sciences 27, 219–239], who reviewed the literature since the mid-1960s. Since the appearance of that survey paper, there has been an increasing interest in scheduling problems with setup times (costs) with an average of more than 40 papers per year being added to the literature. The objective of this paper is to provide an extensive review of the scheduling literature on models with setup times (costs) from then to date covering more than 300 papers. Given that so many papers have appeared in a short time, there are cases where different researchers addressed the same problem independently, and sometimes by using even the same technique, e.g., genetic algorithm. Throughout the paper we identify such areas where independently developed techniques need to be compared. The paper classifies scheduling problems into those with batching and non-batching considerations, and with sequence-independent and sequence-dependent setup times. It further categorizes the literature according to shop environments, including single-machine, parallel machines, flow shop, no-wait flow shop, flexible flow shop, job shop, open shop, and others.     

Effect of boehmite nanorods on the properties of glycidoxypropyl-trimethoxysilane (GPTS) hybrid coatings

AlOOH boehmite nanorods, synthesized by a solid-based process, were incorporated into a sol–gel coating in which GPTS was used as a precursor. Transparent composite coatings with nanorod content up to 40 wt% were obtained by spin coating the sol–gel mixture on glass substrates. Nanorods in the coating were found be aligned parallel to the substrate surface. Mechanical properties, such as modulus and hardness of the nanorod filled coating, were slightly lower than coatings of the same composition but filled with commercially available nanosized boehmite particles. However, crack toughness was greatly improved, as supported by nanoindentation test results. The improvement in crack toughness was attributed to the high aspect ratio of the rigid nanorods, in addition to the fact that the nanorods were aligned within the composite parallel to the surface.     

Aluminum phthalocyanine: an active and simple catalyst for cyanosilylation of aldehydes

Aluminum phthalocyanine (AlPc) in the presence of Ph₃PO acts as a highly effective catalyst for cyanosilylation of various aldehydes to the corresponding cyanohydrin trimethylsilyl ethers. The reaction proceeds smoothly with 5 mol% catalyst loading at room temperature, giving up to 96% yield. Copyright © 2007 John Wiley & Sons, Ltd.