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The dynamics of the bimolecular quenching of triplet excited benzophenone by anisole was studied by nanosecond flash photolysis. We carried out a detailed study of the solvent dependence of the reaction rates and efficiencies in a number of protic and non-protic solvents. These studies were augmented by theoretical modelling and experimental investigation of solute/solvent interactions in the triplet excited and the ground state, respectively. The triplet quenching that follows Stern-Volmer kinetics in all cases is profoundly dependent on the nature of the solvent, with the highest reactivity being consistently found in protic solvents. The results in non-protic solvents are compatible with unproductive quenching via a charge-transfer state, whereas the generally fast quenching in protic solvents is accompanied by efficient formation of free-radical products. Analysis of the solvent dependence in terms of Marcus theory reveals the impact of specific solvation of benzophenone by protic solvents on the ET driving force and kinetics. Specific solvation is found to support efficient free radical ion formation in media of moderate and low polarity as well.

To be or not to be solvated is the decisive parameter that controls the photoinduced hydrogen-atom transfer in diastereomeric ketone/phenol dyads. A kinetic solvent effect that refers to hydrogen bonding between the phenol and the solvent is suggested to be the main source of the stereoselective discrimination in the hydrogen transfer (see figure).

LCA is a popular tool widely used to assess the environmental impact of waste management systems, which is illustrated by the substantial number of LCA computer models specifically addressing this subject. Due to the complex nature of waste management modelling and the range of country-specific data, as well as lack of harmonization, it has been observed that there are large discrepancies between the results using different models. Many studies have underlined the necessity of clearly identifying both the scope and methodological assumptions of LCAs in order to have confidence in the results. Therefore, the paper presented here reveals several methodology-related issues. The study tests two different pieces of LCA software, i.e. IWM-2 (designed specifically for MSW) and SimaPro (a generic and widely used LCA software). The pieces of software were used to LCA an MSW scenario and the results obtained (calculated using Ecoindicator'99 H/A) were compared to show the strengths and weaknesses of these tools, i.e., generic software usually treats the waste as a set of separate fractions, not as a whole mass, which means that the software is not highly sensitive to the composition of the waste and does not take into account the environmental impacts produced as a result of the interaction between the waste components after mixing. As waste composition is very important in planning, one study combines these two software packages to get final results, i.e., data generated by IWM-2 were entered into SimaPro. The discussion is built around a case study in Poland where waste management scenarios have been analyzed. The research carried out has shown that having the same initial inventory data collected on the basis of the same assumptions and with the same boundaries to the system model used and using the same method of LCIA to assess the impact on the environment, may not produce the same end results. In the presented study, the main differences in the LCIA results appeared in four output-related impact categories: carcinogens, climate change, ecotoxicity, and eutrophication/acidification, and for one input related impact category -fossil fuels. Four reasons responsible for these differences are identified:(1) The IWM-2 program identified a smaller number of substances emitted to air and water associated with landfill and recycling than the Ecoinvent database (IWM-2 identified a total of 31 types of emissions to air

Purpose The paper presents, for the first time, a life cycle assessment (LCA) study of energy generation (i.e. electricity and heat production) in Poland. The aim is to determine and compare the potential impact of energy generation upon the environment in 2007, 2010 and 2012 based on countryspecific data bought from specialised government agencies. Methods LCA evaluations were made using the Impact2002+ method, which proposes a feasible implementation of a combined midpoint/damage approach. The method was chosen because it models risks and potential impacts per emission for several thousand chemicals, including greenhouse gas (GHG). The LCA method was used to monitor and assess the current energy system and introduced changes in energy structure at national level. Results and discussion From the environmental perspective, the main problem of the Polish energy sector is that it is mainly based on fossil energy carriers, i.e. hard and brown coal (over 80 %). As the share of renewables in primary energy has increased from 6.7 to 10.2 % (mainly biomass), a reduction in SO 2 , NO x and dust was noted in 2010 in comparison to 2007. Unfortunately, acid and CO 2 emissions increased significantly in 2012 as a result of higher consumption of brown coal as a fuel for energy production. The LCA study shows that the total environmental impact of the production and distribution of 1 TJ of energy increased by about 4 % in 2010 (compared to 2007) and by about 11 % in 2012 (compared to 2010). Conclusions Specific representative data of high quality can be delivered by agencies focused on energy issues and the national statistical office. They can help to considerably reduce the time and costs of life cycle inventory (LCI). These data, including a classification relating to electricity and heat generation and distribution in Poland, were converted to LCA results for the first time. It was noted that allocation between heat and power in the CHP system can be recognised as a source of uncertainty, and the results should be interpreted as sensitive to change in the allocation criteria.

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Purpose Construction, as a sector of the economy, is a significant source of negative environmental impacts. The development of sustainable construction and associated initiatives are meant to reduce that impact. Buildings, for many reasons, are the complex objects of life cycle assessment (LCA) studies, which in this case can be particularly time-, data-and costconsuming. Therefore, an attempt was made to explore the possibility of finding a methodological compromise between a full LCA and the compulsory energy certification. Six methodological variants, so called compromise solutions (CS) were identified and assessed. This article presents the results of the research project financed by the Polish Ministry of Science and Higher Education (N N309 078138) and coordinated by the Wood Technology Institute in Poznan. Methods The proposed CS were hybrids utilising, to various degrees, the environmental life cycle assessment (LCA) and energy certification. Life cycle impact assessments were carried out using IMPACT 2002+. Results and discussion The achieved results showed that the simplifications included in the energy certification lead to a significant drop in environmental impacts (by 77.9 % on average) in relation to the impact calculated for the full LCA. The results closest to the full LCA were achieved by the compromise solution no. 4 (CS4), where simplification included the exclusion from the life cycle of: transport processes, construction site, demolition, final disposal of waste, and the majority of elements associated with the use of the building. CS4 analysed all inventory inputs which were assessed with regard to the entire environmental profile. The following truncation levels were achieved for CS4-10.7 % (conventional masonry building), 9.9 % (passive masonry building), 8.3 % (conventional wooden building) and 7.4 % (passive wooden building), indicating that 90 % of the impact calculated for the full LCA was retained. Conclusions CS4 seems to be a rational compromise between the simplicity of the methodology and the environmental significance. With the exception of the energy usage for heating, hot water and ventilation, CS4 also proposes including, in the analysis, the production of building material and additional elements associated with the use stage, e.g. energy usage for home appliances and lighting, land occupation, water use and wastewater treatment. However, if we were to find a rational minimum, which is close to the energy certification, then a good improvement of this methodology would be to include energy usage for home appliances and lighting as well as introducing conversion indicators, based not only on the depletion of energy resources, but also factoring in global warming and respiratory effects/inorganic compounds. Moreover, it seems that the LCA methodology and, specifically, characterisation factors, are refined to such a degree and scientifically proved that it would be possible to use the knowledge with regard to LCA to establish such indicators for energy certification.

Purpose Among the many publications on the environmental life cycle assessment (LCA) of transport, there are only a few examples of works dedicated to means of internal transport. For this reason, it was decided to gather energy-oriented inventory data and to assess the environmental impact related to the operation of selected forklift trucks, as the most commonly used means of internal transport. This paper presents the main assumptions and the results in relation to the four phases of LCA: the goal and scope definition, the life cycle inventory, the life cycle impact assessment results, and the interpretation. Methods Ten forklifts with different engines were selected in order to carry out the life cycle assessment study. The research was based on the results of measuring the operating fuel consumption and exhaust gas emissions, conducted using the SEMTECH-DS mobile device from the PEMS group of devices. In order to make the measurements under a circumstance close to the real conditions of forklift exploitation, it was decided to slightly modify the operating cycle proposed in VDI 2198. The environmental impact of the fuel/electricity usage and exhaust gas emissions was assessed using the ISO 14040x guidelines and the IMPACT 2002+ method. Results and discussion The study showed that using an electric forklift to transport 1 t of payload over a distance of 1 km has a significantly smaller environmental impact than using one of the selected forklifts powered by an internal combustion engine. Using forklifts powered by liquefied petroleum gas (LPG) engines leads to a significantly higher environmental impact whilst the use of vehicles with diesel engines has an impact at a level several times lower. In a case of drives without load, where functional unit was defined as covering 1-km distance with no vehicle load, a lower impact for the electric vehicles was also obtained. The analysis includes the influences of the upstream processes of fuel and electrical energy production. Conclusions Even when Poland's production scenario (based almost entirely on fossil fuels) is taken into consideration, the electric forklifts still show a clear advantage. It should be expected that, if the technological mix of electrical energy production for countries with a higher share of renewable or nuclear energy were to be taken into account, the environmental indicators for electric vehicles would be even lower. It is worth noting that only the energy aspects of forklift operation were analysed. Further studies aiming to collect inventory data relating to other exploitation aspects, as well as the production and utilization of the same vehicles, are planned as a continuation of this research.