Benefits of mesopores in sulfated zirconia catalyst

Activities of two catalysts obtained from hydroxide and alkoxide precursors were correlated to their different structural and textural properties. Activity is mainly determined by the presence of active tetragonal phase, which is more stable at high temperatures in the catalyst of alkoxide origin than in one from hydroxide. An appropriate structure must be accompanied with beneficial pore structure, as is the case of mesopores of the catalyst from alkoxide. In the case of very small pores of the catalyst from hydroxide precursor, activity is negligible due to pores plugged by coke.     

Clinical Trials and Basic Research in Photodynamic Diagnostics and Therapies from the Center for Laser Diagnostics and Therapy in Poland

The purpose of this review is to present an overview of the development of photodiagnostic and photodynamic therapy (PDD and PDT) techniques in Poland. The paper discusses the principles of PDD, including fluorescent techniques in determining precancerous conditions and cancers of the skin, digestive tract, bladder and respiratory tract. Methods of PDT of cancer will be discussed and the current state of knowledge as well as future trends in the development of photodynamic techniques will be presented, including the possibility of using photodynamic antimicrobial therapy. Research pioneers in photodynamic medicine such as Thomas Dougherty are an inspiration for the development of methods of PDD and PDT in our Clinic. The Center for Laser Diagnostics and Therapy in Bytom, Poland, promotes the propagation of PDD and PDT through the training of clinicians and raising awareness among students in training and the general public. Physicians at the Center are engaged in photomedical research aimed at clinical implementation and exploration of new avenues in photomedicine while optimizing existing modalities. The Center promotes dissemination of clinical results from a wide range of topics in PDD and PDT and serving as representative authorities of photodynamic medicine in Poland and Europe.     

Water uptake analysis of acceptor-doped lanthanum orthoniobates

In this work, lanthanum orthoniobates doped with either antimony, calcium, or both have been synthesized and studied. The water uptake of the investigated materials has been analyzed by means of thermogravimetric studies. The results show the difference between the thermodynamics of hydration between the lanthanum orthoniobate system and other proton conducting ceramics. The relation between the water uptake and effective acceptor doping for the investigated system has been found, and the energetics of the water uptake relation are discussed.

     

Zinc oxide films and nanomaterials for photovoltaic applications

We provide an overview of ZnO applications in solar cells. ZnO (and ZnO‐based materials) can be used as electrodes and/or scattering/light trapping layers, as well as electron transport layers in solar cells based on nanoparticles and organic materials (polymer solar cells, dye‐sensitized solar cells). For each of these applications, we will briefly summarize common research directions, as well as existing problems and unresolved questions. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Performance Analysis of Nonlinear Energy‐Harvesting DF Relay System in Interference‐Limited Nakagami‐m Fading Environment

A decode‐and‐forward system with an energy‐harvesting relay is analyzed for the case when an arbitrary number of independent interference signals affect the communication at both the relay and the destination nodes. The scenario in which the relay harvests energy from both the source and interference signals using a time switching scheme is analyzed. The analysis is performed for the interference‐limited Nakagami‐m fading environment, assuming a realistic nonlinearity for the electronic devices. The closed‐form outage probability expression for the system with a nonlinear energy harvester is derived. An asymptotic expression valid for the case of a simpler linear harvesting model is also provided. The derived analytical results are corroborated by an independent simulation model. The impacts of the saturation threshold power, the energy‐harvesting ratio, and the number and power of the interference signals on the system performance are analyzed.     

A Terphenyl Supported Dioxophosphorane Dimer: the Light Congener of Lawesson's and Woollins’ Reagents

Thermolysis of a 1,3-dioxa-2-phospholane supported by the terphenyl ligand Ar^iPr4 (Ar^iPr4=[C₆H₃-2,6-(C₆H₃-2,6-iPr₂)]) at 150 °C gives [Ar^iPr4PO₂]₂ via loss of ethene. [Ar^iPr4PO₂]₂ was characterised by X-ray crystallography and NMR spectroscopy; it contains a 4-membered P−O−P−O ring and is the isostructural oxygen analogue of Lawesson's and Woollins’ reagents. The dimeric structure of [Ar^iPr4PO₂]₂ was found to persist in solution through VT NMR spectroscopy and DOSY, supported by DFT calculations. The addition of DMAP to the 1,3-dioxa-2-phospholane facilitates the loss of ethene to give Ar^iPr4(DMAP)PO₂ after days at room temperature, with this product also characterised by X-ray crystallography and NMR spectroscopy. Replacement of the DMAP with pyridine induces ethene loss from the 1,3-dioxa-2-phospholane to provide gram-scale samples of [Ar^iPr4PO₂]₂ in 75 % yield in 2 days at only 100 °C.