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A novel protocol for the synthesis of para-quinols from inexpensive phenols based on a chemoenzymatic cascade reaction is reported. The protocol combines an enzymatic oxidation of hydroquinones to benzoquinones and their transformation in situ to p-quinols via a catalytic process. Mild ambient conditions and a thoroughly optimized catalytic system provide target products with excellent yields. In an advancement of previous classical approaches, the scope of products available has been extended. It should be noted that the enzyme not only participates in the oxidation reaction of hydroquinones, which is the first step of the chemoenzymatic cascade, but also modulates the activity of the metal catalyst in a highly effective manner, significantly increasing the efficiency of the carbon–carbon bond formation in the second step. This specific interaction of the protein with the metal is also manifested in the stereochemical course of the addition reaction of vinyl aryl boronic acid, resulting in the enhancement of the Z/E ratio. The developed cascade approach allowed for the elimination of side-products, thus increasing the atom economy of the process and simplifying the purification step. Moreover, the versatility of the method was demonstrated on 19 examples in isolated product yields up to 99%. In addition, the possibility of reuse of both the catalytic system and the reaction medium reduces the amount of waste and the cost of the process. [ABSTRACT FROM AUTHOR]

ORC (Organic Rankine Cycle) is widely used to convert low temperature heat into electricity using organic working fluid. The performance of an ORC installation is influenced deeply by selected working fluid and operation conditions. Recently has been presented a new generation of working fluids dedicated to ORC systems. They are characterized by near zero ODP (Ozone Depletion Potential) coefficient and significantly smaller GWP (Global Warming Potential) in comparison with currently used refrigerants. This paper presents preliminary research on selected dry and isentropic ORC fluids and some peculiarities in their behaviour.

This paper details the development of a systematic methodology to integrated life cycle assessment (LCA) with thermo-economic models and to thereby identify the optimal exploitation schemes of geothermal resources. Overall geothermal systems consist of a superstructure of geothermal exploitable resources, a superstructure of conversion technology and multiple demand profiles for Swiss city. In this paper, an enhanced geothermal system has been chosen as exploitable resources. The energy conversion technology used in modelling is an organic Rankine cycle, which can be used to supply heat and electricity. In the Swiss case four demand profiles periods are considered: summer, interseason, winter and extreme winter, the city Nyon serving for the example case study. The multi-objective optimization system, that uses an evolutionary algorithm, is employed to determine the optimal scheme for some of the prepared models, with exergy efficiency and environmental impact as objectives.

Next 10-15 years are crucial for condition of Polish energy sector in light of challenges arising mainly from increasing demand for electric energy, need of reducing greenhouse gases emissions and shutdowns of old units. In this situation cogeneration can be one of the most rational way to meet those circumstances. This paper analyzes present development of cogeneration in Poland and its prospect for future.

As chemotherapy suffers from the limitation of non-selectivity towards cancer cells, resulting in severe side effects, the targeted delivery of anticancer drugs such as cisplatin using nontoxic nanomaterials has been under extensive examination. In such an approach, qualities such as biocompatibility, biodegradability, ease of synthesis (including the surface modifying possibility with targeting ligands), and the tunable encapsulation of chemotherapeutics make liposomes superior to other nanomaterials as drug nanocarriers. Despite ten liposome-drug formulations being approved for the market, none of them concern platinum-based anticancer drugs. This can be due to the problematic multistep synthesis of such systems and the use of ineffective analytical tools for their characterization. Consequently, the current study aims to propose a straightforward protocol for liposome–cisplatin system synthesis as well as a comprehensive method for their characterization based on the combination of capillary electrophoresis (CE) and inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS). Although the application of CE-ICP-MS has been reported in previous studies on liposome–cisplatin systems, the advantages of the optimized method proposed in our study include not only the possibility of the direct quantitative monitoring of liposome–metallodrug systems (all analytes of interest) but also their interactions with proteins in close-to-physiological conditions of analysis due to the applied tandem mass mode of the spectrometer. The present approach thereby facilitates overcoming the limitations of the strategies previously described in the literature, especially in the case of sulfur monitoring. [ABSTRACT FROM AUTHOR]