The Mechanism of the Photodimerization of [60]Fullerene Derivatives: It is Still a Charge Separation Followed by a Back Transfer!

Herein, we present a systematic study of the photochemical behavior of a set of fullerene compounds bearing various organic addends attached to the fullerene cage. It has been shown that the yield of photodimerization products strongly depends on the structure and electronic properties of the material, primarily the electron affinity (acceptor strength) of the modified fullerene core. This finding being inconsistent with the conventional [2+2]cycloaddition mechanism and pointed to an alternative pathway. This proposed pathway involves photoinduced charge separation followed by back charge transfer events leading to the efficient generation of triplet excitons, which are responsible for the formation of dimerized species. The light-induced charge separation pathway was confirmed by electron spin resonance spectroscopy and was supported by theoretical calculations. The revealed mechanism allows one to control the photochemical behavior of the fullerene derivatives via rational structural engineering: some of the compounds were shown to be fully resistant to photodimerization, which makes them promising candidates in the development of stable organic photovoltaics. Furthermore, this approach could be used to suppress back charge transfer in donor-acceptor blends and hinder the formation of triplet excitons which represents one a major energy loss channel in the current generation of organic solar cells.     

Entrepreneurial universities and the dynamics of academic knowledge production: A case study of basic vs. applied research in Belgium

This paper explores issues related to the impact of Science-Industry relationships on the knowledge production of academic research groups, in particular on the alleged shift to the more applied research end under the influence of business partners' needs. Our findings from a case study of the Belgian Katholieke Universiteit Leuven ((K.U. Leuven) show a significant steady growth over time of publications produced by academic research groups involved in University-Industry linkages, closely related to factors both internal and external to the university that have stimulated academic entrepreneurial behaviour. On an aggregated level for 1985-2000, basic research publications appear to be more present than applied ones, both in total numbers and in growth rates. Our findings show that applied and basic research publications generally rose together in the same year. No clear and generalised evidence of a shift towards the applied research end determined by the involvement in U-I linkages was found, the weak indications of such a shift within groups coming only for groups that have already high applied versus basic orientation. These results suggest that the academic research groups examined have developed a record of applied publications without affecting their basic research publications and, rather than differentiating between applied and basic research publications, it is the combination of basic and applied publications that consolidate the group's R&D potential. Accordingly, critical assessments of the University side of the emerging 'Triple Helix' need to take into account the dynamic nature of the research dimension.     

Integration of binding peptide selection and multifunctional particles as tool-box for capture of soluble proteins in serum

In this paper, we report on a general approach for the detection of a specific tumoural biomarker directly in serum. Such detection is made possible using a protein-binding peptide selected through an improved phage display technique and then conjugated to engineered microparticles (MPs). Protein biomarkers represent an unlimited source of information for non-invasive diagnostic and prognostic tests; MP-based assays are becoming largely used in manipulation of soluble biomarkers, but their direct use in serum is hampered by the complex biomolecular environment. Our technique overcomes the current limitations as it produces a selective MP—engineered with an antifouling layer—that ‘captures’ the relevant protein staying impervious to the background. Our system succeeds in fishing-out the human tumour necrosis factor alpha directly in serum with a high selectivity degree. Our method could have great impact in soluble protein manipulation and detection for a wide variety of diagnostic applications.     

Activated carbon derived from macadamia nut shells: an effective adsorbent for phenol removal

In this study, activated carbon based on the waste macadamia nut shells (MAC) was investigated for potential use as an adsorbent for phenol removal. The pseudo second-order kinetic model best described the adsorption process. The extent of the phenol adsorption was affected by the pH solution and the adsorbent dosage. Equilibrium data fitted well to the Langmuir model with a maximum adsorption capacity of 341 mg g^?1. The calculated thermodynamic parameters suggested that the phenol adsorption onto MAC was physisorptive, spontaneous and exothermic in nature. Phenol desorption from loaded adsorbent was achieved by using 0.1 mol L^?1 NaOH, ethanol (100 %) and deionized water.     

Numerical methods for minimizing real functions unimodal on a set

Abstract An extension of the classical concept of unimodality was recently proposed in [4] and slightly modified in [5]. Here we present a numerical method based on the idea of bisection for determining the minimum points of a real unimodal function on a set. A serial and a parallel algorithm are given.     

Effect of plasticizer on production of bioactive synthetic calcium phosphates/glass composites and their properties

Bioactive synthetic calcium phosphates/glass composites have been produced using PVA as a plasticizer (0, 10, 15, 20 mass%). Changes in the linear, volumetric and weight parameters of samples upon sintering at 800 °C as well as in the density, porosity and compression strength have been investigated. It was established that all of the ceramics studied (both produced with and without PVA) exhibit a linear (0.7–1.9%) and volumetric (2.3–4.9%) shrinkage, which increases with using PVA and raising its content. The microstructure examination of samples obtained with a plasticizer revealed a complex porous morphology and the presence of complex-shaped 10–50 µm pores. An increase in PVA amount led to transformation of a flake-like structure and formation of particles of regular rounded shape. The pycnometric density did not depend on using PVA and equaled 2.58–2.61 g/cm³. PVA promoted an increase in the total porosity from 24.7 to 35.8% and a decrease in the density by 1.66 to 1.89%. Porosity increased proportionally to the amount of introduced PVA and was the highest for composites produced with 20 mass% addition of PVA. Open porosity dominated in all of the composites with PVA addition. The ultimate compression strength was in the range 42–93 MPa and reduced with increasing PVA amount.