Technical efficiency,managerial efficiency and objective-setting in the educational system: an international comparison

This study uses data envelopment analysis to analyse the efficiency of educational systems in 31 countries. This type of evaluation is of interest both when formulating a model for analysis and when applying such a model empirically. The efficiency of an educational system must take into account the students' economic and social background, as this is an environmental factor that decisively influences their performance. This is a highly important aspect and so we propose a specific evaluative process for it. Secondly, we evaluate the efficiency of educational systems in different countries, an analysis that has few forerunners since the majority of previous research has focused on analysing a single country. The results suggest that, in general, the most efficient management of educational systems can be found in those countries with a Communist past. They also suggest that there is a series of developed countries, which, judging by the results obtained, could increase their students' performance with even fewer resources than those currently allocated to their educational systems.     

Fiber optic multi-channel protein detector for use in preparative continuous annular chromatography

On-line coupling continuous-flow liquid membrane extraction (CFLME) with HPLC, a novel automatic system was developed for the determination of sulfonylurea herbicides in water. After an automatic trace-enrichment process by CFLME, which is the combination of continuous flow liquid-liquid extraction and support liquid membrane (SLM) extraction, the target analytes were concentrated in 50 microl of 0.2 M Na2CO3-NaHCO3 (pH 10.0) buffer. The concentrated sample solutions were injected directly onto a C18 analytical column with a valve, and detected at 240 nm with a diode array detector. Metsulfuron methyl (MSM), and DPX-A 7881 were baseline separated with a mobile phase consisting of methanol and 67 mM KH2PO4-Na2HPO4 (pH 5.91) buffer (45+55, v+v) at a flow-rate of 1.0 ml min(-1). With an enrichment time of 10 min and enrichment sample volume of 20 ml, the enrichment factors and detection limits are 100 and 0.05 microg l(-1) for MSM, and 96 and 0.1 microg l(-1) for DPX-A 7881, respectively. The linear range and precision (RSD) are 0.1-50 microg l(-1) and 7.0% for MSM, and 0.2-50 microg l(-1) and 9.2% for DPX-A 7881, respectively. This proposed method was applied to determine MSM and DPX-A 7881 in seawater, tap water, and bottled mineral water with spiked recoveries in the range of 83-95% for MSM and 88-100% for DPX-A 7881, respectively.     

Experimental and Computational Study of the Thermal Decomposition of 3‐Methyl‐3‐buten‐1‐ol in m‐Xylene Solution

An experimental study of the thermal decomposition of a β‐hydroxy alkene, 3‐methyl‐3‐buten‐1‐ol, in m‐xylene solution, has been carried out at five different temperatures in the range of 513.15–563.15 K. The temperature dependence of the rate constants for the decomposition of this compound in the corresponding Arrhenius equation is given by ln k (s^?1) = (25.65 ± 1.52) ? (17,944 ± 814) (kJ·mol^?1)·T^?1. A computational study has been carried out at the M05–2X/6–31+G(d,p) level of theory to calculate the rate constants and the activation parameters by the classical transition state theory. There is a good agreement between the experimental and calculated rate constants and activation Gibbs energies. The bonding characteristics of reactant, transition state, and products have been investigated by the natural bond orbital analysis, which provides the natural atomic charges and the Wiberg bond indices. Based on the results obtained, the mechanism proposed is a one‐step process proceeding through a six‐membered cyclic transition state, being a concerted and slightly asynchronous process. The results have been compared with those obtained previously by us (Struct Chem 2013, 24, 1811–1816) for the thermal decomposition of 3‐buten‐1‐ol, in m‐xylene solution. We can conclude that in the compound studied in this work, 3‐methyl‐3‐buten‐1‐ol, the effect of substitution at position 3 by a weakly activating CH₃ group is the stabilization of the transition state formed in the reaction and therefore a small increase in the rate of thermal decomposition.     

Enantiopure Ferrocene‐Based Planar‐Chiral Iridacycles: Stereospecific Control of Iridium‐Centred Chirality

Reaction of [IrCp*Cl₂]₂ with ferrocenylimines (Fc=NAr, Ar=Ph, p‐MeOC₆H₄) results in ferrocene C?H activation and the diastereoselective synthesis of half‐sandwich iridacycles of relative configuration S_p*,R_Ir*. Extension to (S)‐2‐ferrocenyl‐4‐(1‐methylethyl)oxazoline gave highly diastereoselective control over the new elements of planar chirality and metal‐based pseudo‐tetrahedral chirality, to give both neutral and cationic half‐sandwich iridacycles of absolute configuration S_c,S_p,R_Ir. Substitution reactions proceed with retention of configuration, with the planar chirality controlling the metal‐centred chirality through an iron–iridium interaction in the coordinatively unsaturated cationic intermediate.     

Structural and Kinetic Aspects of Blood Plasma Protein Adsorption on the Surface of Hydrophobic Polymers

Abstract

Due to the wide use of polymers in medicine, researchers are required to solve a very important problem–to understand the interaction between materials of nonphysiological origin and the surrounding biological liquids, and tissues, particularly blood.     

Fully differential cross sections for photo-double-ionization of D2

We report the first kinematically complete study of the four-body fragmentation of the D2 molecule following absorption of a single photon. For equal energy sharing of the two electrons and a photon energy of 75.5 eV, we observed the relaxation of one of the selection rules valid for He photo-double-ionization and a strong dependence of the electron angular distribution on the orientation of the molecular axis. This effect is reproduced by a model in which a pair of photoionization amplitudes is introduced for the light polarization parallel and perpendicular to the molecular axis.