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Most EU countries are trying to develop new sources of energy to meet local power requirements due to energy shortages. The most popular renewable energy developments include biogas stations, wind turbines, water turbines, and solar systems. This article focuses on reviewing studies concerning the utilization of solar energy systems, especially photovoltaic (PV) ones, in European countries such as Germany, Italy, Spain, and Poland, which are leaders in PV installations. The review identifies factors influencing the development of PV investments and the energy situation in these countries. Economic, market, environmental, and infrastructural barriers, as well as driving factors, are presented. In all countries, the majority of installations were in the prosumer sector, with only a very small percentage in the state-owned sector. The methodology of the study covered the mentioned barriers, which were identified using scientific databases such as Scopus, Web of Science, and branch organizations websites like the International Renewable Energy Agency (IRENA). The novelty of the article lies in its examination of special barriers concerning green energy production in chosen EU countries. Normally, when reading articles on PV installations, as presented in the References section, one primarily observes a description of the construction process without deep involvement in the presented ideas. [ABSTRACT FROM AUTHOR]

Human activities in relation to aquatic ecosystems result in significant economic losses in the form of contamination of water sources, deteriorating its quality and therefore its availability in lakes, water bodies and even in soil. Hence the need for systematic revitalisation or reclamation of water ecosystems. Such actions, in order to be rational, require a detailed understanding of the causes, and then the use of appropriate technology. The need for the above-mentioned actions result from the weather changes that have been noticeable in recent years, as well as environmental pollutants increasing water eutrophication in reservoirs and stimulating the development of some species of cyanobacteria. These cyanobacteria can cause serious water poisoning, especially in water supply systems. Therefore, a rational, comprehensive technology for the removal of bottom sediments and their processing into organic and mineral fertiliser has been developed with properties similar to manure. It also creates opportunities to improve the structure of soils thanks to the supply of organic carbon, the loss of which was found, among others, in also in soils of Poland and EU. These new possibilities of revitalisation hitherto unknown make it possible to a large extent, compliance with environmental requirements when revitalising water reservoirs and soil. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The low frequency Raman spectral density associated with the intermolecular hydrogen-bonding interaction of benzoic acid in chloroform was investigated through the ultrafast optically-heterodyne-detected optical Kerr effect. The low-frequency solute Raman spectrum was obtained by Fourier transform analysis and subtraction of the solvent spectrum from the solution spectrum. The resulting difference spectrum has a broad band below 150 cm-1 with a peak at around 80 cm-1. Previous studies of aromatic liquids suggest that the origin of such a low-frequency band is librational motion, although intermolecular hydrogen-bonding modes in benzoic acid may also contribute. To clarify these contributions to the low-frequency band, methyl benzoate was used to estimate the librational component; its structure is similar to benzoic acid, but it forms no intermolecular hydrogen bonds. Both librational and intermolecular modes were found to contribute to the low-frequency Raman spectrum of the dimer and thus can be separated. These experimental results were compared with the results of density functional theory calculations. In addition, the effect of deuteration on the Raman spectrum was also investigated. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The level of sustainability of animal production depends on the use of modern housing systems which ensure high productivity and quality of milk and meat, with the possibility of robotization of work, by simultaneously minimizing the negative impact on the environment, including energy inputs by using renewable energy sources and ensuring livestock animals' welfare. Livestock production, especially milk production, is a source of significant amounts of harmful gases such as carbon dioxide and ammonia. The main aim of the research was a multicriterial investigation of free-stall cattle barns for dairy cows taking into account sustainability of production. Twelve free-stall cattle barns were tested with boxed litter and non-litter systems, and with deep litter, four barns in each system. Original methodology was elaborated which allowed for the technological, economic and environmental assessment of cattle barns and their elements of infrastructure. The methodology scheme consisted of the following stages: stage 1 - choice of objects for research, stage 2 - characteristics of objects tested, stage 3 - identification of key elements characteristic of the objects tested which are helpful for technical, technological, quality and economic assessment, stage 4 - determination of these parameters, stage 5 - model of final assessment and choice of the best, most convenient technological-functional solutions, stage 6 - designing exemplary models. The parameters obtained from tests allowed the selection of the best solutions, to be applied in new designs which comply with the requirements of standards, including welfare, environmental protection and minimization of energy inputs. Based on research results, three model proposals of functionaltechnological solutions for cattle barns were elaborated. The first proposed example was a free-stall boxed cattle barn with litter. The second best solution was a non-littered boxed cattle barn. The third model proposed was a cattle barn with deep litter. All three barns are considered to have very good microclimate parameters, by dint of the proper construction of the adjustable ventilation system. Also, investment costs and energy inputs could be at a level acceptable by investors thanks to high automation and robotization. [ABSTRACT FROM AUTHOR]

Hydrogen-bonded liquids are excellentsolvents, in part due tothe highly dynamic character of the directional interaction associatedwith the hydrogen bond. Here we study the vibrational and reorientationaldynamics of deuterated hydroxyl groups in various primary alcoholsusing polarization-resolved femtosecond infrared spectroscopy. Weshow that the relaxation of the OD stretch vibration is similar forethanol and its higher homologues (∼0.9 ps), while it is appreciablyfaster for methanol (∼0.75 ps). The fast relaxation for methanolis attributed to strong coupling of the OD stretch vibration to theovertone of the CH3rocking mode. Subsequent to excitedstate relaxation, the dissipation of the excess energy leads to structuralrelaxation of the alcohol liquid structure. We show that this relaxationof the H-bonded network depends on the alkyl chain length. We findthat the anisotropy of the excitation decays by both thermal diffusionfrom excited OD groups to nonexcited molecules and reorientationalmotion. The reorientation is described well by a model employing tworelaxation times that increase linearly with increasing alcohol size.The short reorientation time is assigned to the partial reorientationof molecules within the alcohol cluster, while the long reorientationtimes can be attributed to breaking and reforming of hydrogen bonds. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, the complex and heterogeneous structure of ionic liquids has been demonstrated; however, the consequences on the dynamics have remained elusive. Here, we use femtosecond IR spectroscopy to elucidate the local structural dynamics in protic alkylammonium-based ionic liquids. The structural relaxation after an ultrafast temperature increase, following vibrational excitation and subsequent relaxation of the N-D (or N-H) stretching vibration, is found to vary substantially between the ionic and hydrophobic subdomains. The dynamics in the ionic domains are virtually unaffected by the alkyl chain length and is, therefore, decoupled from viscosity. Equilibration within the hydrophobic subdomains, as evident from the dynamics of the C-H stretching vibration, is faster than that in the ionic domains and shows a remarkably low thermal activation. [ABSTRACT FROM AUTHOR]

The behavior of water molecules surrounding a protein can have an important bearing on its structure and function. Consequently, a great deal of attention has been focused on changes in the relaxation dynamics of water when it is located at the protein surface. Here we use the ultrafast optical Kerr effect to study the H-bond structure and dynamics of aqueous solutions of proteins. Measurements are made for three proteins as a function of concentration. We find that the water dynamics in the first solvation layer of the proteins are slowed by up to a factor of 8 in comparison to those in bulk water. The most marked slowdown was observed for the most hydrophilic protein studied, bovine serum albumin, whereas the most hydrophobic protein, trypsin, had a slightly smaller effect. The terahertz Raman spectra of these protein solutions resemble those of pure water up to 5 wt % of protein, above which a new feature appears at ∼80 cm–1, which is assigned to a bending of the protein amide chain. [ABSTRACT FROM AUTHOR]

Nettle is most often studied as a spinning plant, as a source of biochemicals and environmentally safe fungicides. Major studies are mostly conducted on natural samples and plant populations. Prospects for the use of plant biological resources of stinging nettle (Urtica dioica L.) from the Cretaceous south of the Central Russian Upland to create cultivars for a wide range of applications are considered. The aim of the study is to investigate the productivity of fresh weight and its biochemical composition in the variety of stinging nettle Avicenna, created on the basis of the initial material selected in the Belgorod region of Russia and patented in 2019, and new promising cultivars UD 32/06 and UD 12/16. The experiments were carried out by the split plot method with full randomization in four replicates. The cultivars UD 32/06 and UD 12/16 reliably surpass the Avicenna cultivar in the collection of fresh mass weight by 16.6–22.7% and 23.1 to 27.8%, dry weight by 11.4–28.7% and 1.9–32.7%, and seeds by 19.7–32.0% and 23.2–40.0% accordingly. Analysis of variance showed a significant effect of the factor "Cultivar" on the productive traits "Fresh weight yield" (strength influence 87.2%), "Dry weight yield" (strength influence 43.9%), and "Seed yield" (h2x = 61.6%). The content of crude protein in dry weight of the Avicenna and new varieties is 21.1–24.2%, crude fat: 2.5–4.2%, fiber: 12.0–14.8%. High content of ascorbic acid, calcium, phosphorus, iron, and zinc were observed in all material tested. It is concluded that the biological resources of the wild-growing forms of Urtica dioica L. from the European south of Russia are a valuable source material for obtaining varieties, and varieties with high productivity of the aboveground mass and stable seed productivity. The obtained research results prove the usefulness of nettle cultivation. [ABSTRACT FROM AUTHOR]