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Legislative Impact on Significance of RES in the Latvian Energy Market

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Journal of Environmental Science and Engineering(B) 2012年第5期1卷 611-619页

作者： peteris shipkovs Galina Kashkarova Lana Migla Ilze Purina Kristina Lebedeva Energy Resources Laboratory Institute of Physical Energetic Riga 1006 Latvia Faculty of Civil Engineering Heat Gas and Water Technology Institute Riga Technical University Riga 1048 Latvia

Latvia is a new European Union country, with 20-year experience in the efforts to develop the energy policy that would favour reliable supply of the state with energy and promote its effective and rational utilization. The energy law should take into consideration the technological progress and increasing energy consumption as well as the poorly regulated sphere of production and utilization. At present, new regulations are needed, as the existent ones have become outdated and unable to ensure stable development of the energy sector. However, the lack of experience and sometimes external influence could lead to a situation when the new law would not be conducive to the industrial development but vice-versa-would slow it down. Since Latvia has been confronted by counterproductive laws, it is highly important to estimate beforehand the future impact of legislation on the state economy. On issue of for the country is now to guarantee-by force of law-the optimal share of renewable energy in the national energy mix. The objective set within the framework of European Union policy is to achieve a 40% share of renewable energy by 2020; therefore, it is necessary to work out a separate law concerning the RES （renewable energy sources）. The new RES law is to regulate support and to promote increase in the share of renewable. However, there are many influencing factors--not clearly specified outlooks for the energy sector and national economy development, the interests of energy importers, lobbying, etc.; these factors can make the RES law not only ineffective but even negatively affecting the RES share stability in the state energy balance. It is therefore essential, before the law has been adopted, to thoroughly analyze it so that the optimal variant is accepted.

关键词： Renewable energy sources energy market energy legislation.

(2-Hydroxyethyl)ammonium Lactates—Highly Biodegradable and Essentially Non-Toxic Ionic Liquids

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Green and Sustainable Chemistry 2011年第3期1卷 103-110页

作者： Sanita Pavlovica Andris Zicmanis Elina Gzibovska Maris Klavins peteris Mekss 不详

(2-Hydroxyethyl)ammonium lactates have been prepared by reactions of the corresponding (2-hydroxyethyl) amines with lactic acid and characterized by their 1H NMR, IR, and mass spectra. They have been quantita- tively analyzed by HPLC, and their water contents have been determined by the Karl-Fischer method. The title salts are low-melting solids or viscous liquids, and they belong to the class of polar, hydrophilic ionic liquids. The toxicity and chemical and biological degradation of the synthesized ionic liquids have been evaluated by methods described in European Standards. The measurements showed these ionic liquids to be highly biodegradable and only slightly toxic substances. Condensation reactions of benzaldehyde with ethyl cyanoacetate and with acetophenone have been performed in these materials as solvents. The possibility of simultaneously applying these ionic liquids as both solvents and catalysts for the mentioned reactions has been demonstrated, as well as repeated use of the same ionic liquid for a number of condensation reactions without any purification.

关键词： Ionic Liquids Biodegradation Toxicity Polarity Condensation Reactions

Self-Enhancement of Scalar and Vector Holographic Gratings in Azobenzene Molecular Glassy Films

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Optics and Photonics Journal 2014年第6期4卷 143-152页

作者： Andris Ozols Valdis Kokars peteris Augustovs Dmitrijs Malinovskis Kaspars Traskovskis Elmars Zarins Girts Ivanovs Faculty of Electronics and Telecommunications Riga Technical University Riga Latvia Faculty of Material Science and Applied Chemistry Riga Technical University Riga Latvia

Self-enhancement (SE) effect of scalar and vector holographic gratings (HG) recorded in three different azobenzene molecular glassy films is experimentally studied in both transmission and reflection modes at 532 and 633 nm. The maximal SE factor (the ratio of diffraction efficiency to its initial value) SEF = 42 has been achieved. It is shown that the model of complementary HG can be applied also in scalar transmission thin HG case to explain coherent SE. The possibility of vector HG coherent SE in transmission mode is experimentally demonstrated for the first time (SEF = 4.3). The possibility of coherent HG SE in reflection mode is also established for the first time (SEF = 21). HG recording processes as well as coherent SE processes are found to be independent in transmission and reflection modes being determined by volume and surface relief HG, respectively. The permittivity gradient mechanism is proposed to explain the coherent SE of surface relief HG. Both HG recording and coherent SE efficiencies strongly decrease when HG period is decreased from 2 mm to 0.5 mm. No relaxational SE effect is found. Coherent SE effect in molecular glasses is found to be weaker than in inorganic materials.

关键词： Self-Enhancement of Holograms Light Polarization Holographic Gratings Azobenzene Molecular Glasses

Red Beetroot Juice and Stamina: An Experimental Study

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Journal of Biosciences and Medicines 2022年第9期10卷 18-29页

作者： Galina Smirnova peteris Tretjakovs Anna Fedotova Raimonds Simanis Svetlana Vasiļjeva Olegs Suhorukovs Dalija Seglina Inta Krasnova Vadims Bartkevics Dmitry Babarykin Institute of Innovative Biomedical Technology Ltd. Riga Latvia Institute of Biology of the University of Latvia Riga Latvia Riga Stradins University Riga Latvia Hospital of Traumatology and Orthopaedics Riga Latvia Institute of Horticulture Dobele Latvia Institute of Food Safety Animal Health and Environment Riga Latvia

Introduction: Red beet juice is increasingly used in sports to enhance the endurance of athletes. To increase the specific efficiency of red beet juice, the method of its fractionation by ultrafiltration was used for the first time. The purpose of the study was to evaluate the effect of fractionated beetroot juice on the strength and endurance of laboratory rats. Methods: Male Wistar rats (6 groups;n = 10) were used in the study. In addition to the standard chow, some groups of rats 2 h before the exercises received 0.5 ml of native (RBJ) or fractionated (FRBJ) per os. Three groups of animals were trained using a motorized wheel with a gradual speed increase over four weeks: 20 min/day for five days a week. Muscle strength of animals in all groups was measured by electronic dynamometry and the endurance of rats was evaluated once a week using electrical stimulation on a racetrack which moved at a speed of 15 m/min. The test was performed an hour after the ingestion of RBJ or FRBJ. At the end of the experiment, biochemical blood indices were determined. FRBJ was prepared by the original method. Results: Most significant differences in the chemical composition of RBJ and FRBJ were found for glutamic acid, of which the content was 67.2% higher than in native juice. The greatest changes during the experiment were in the mass of the rats’ calf muscles. Regular running exercise caused a 29% increase in muscle mass. The additional increase in m. gastrocnemius was also provided y FRBJ – 12%. The combination of physical activity and the introduction of red beet derivate led to the increase of the calf muscle mass by 121% within a month. Assessing the endurance of animals by frequency of falling from the treadmill, we can conclude that compared with untrained animals, trained rats receiving FRBJ had three times higher levels of endurance. Conclusion: Consumption of FRBJ led to increased muscle strength in rats and the ergogenic effect of the product was significantly higher i

关键词： Red Beetroot Ultrafiltration Running Trained Rats Muscle Strength Endurance Anabolic Effect Glutamic Acid