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Synthetic approaches to dexmedetomidine (review)

Abstract

The review is an attempt at critical evaluation of known synthetic procedures used for laboratory and industrial preparation of a synthetic antihypertensive - Dexmedetomidine as to their complexity, published yield and atom economy

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Laboratory and industrial synthesis of remifentanil

Abstract

The submitted review aims at critical evaluation of known synthetic procedures utilized both for laboratory and industrial production of the synthetic analgesic - remifentanil as to their simplicity, published yield and atom economy.

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Nanostructured materials for solar hydrogen production

Abstract

One of the main requirements for a future Hydrogen Economy is a clean and efficient process for producing hydrogen using renewable energy sources. Hydrogen is a promising energy carrier because of its high energy content and clean combustion. In particular, the production of hydrogen from water and solar energy, i.e., photocatalysis and photoelectrolysis, represent methods for both renewable and sustainable energy production. Here, we will present the principles of photocatalysis and the PhotoElectroChemical cell (PEC cell) for water splitting, along with functional materials. Defect chemical aspects will be high-lighted. To date, the decreasing length scale to the nanoscale of the functional materials attracts widespread attention. The nanostructure is beneficial in case diffusion lengths of the photo-generated charge carriers are substantially different.

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Catalytic conversion of ethanol into alkenes and acetaldehyde

Abstract

Bioethanol is an example of a renewable energy source which can be produced not only by fermentation of simple sugars but also by depolymerisation of cellulose, as the second-generation feedstock, in the first step. This will help to further develop the bioethanol economy. Ethanol can be used as a promising platform molecule for the production of a variety of industrially important chemicals such as alkenes or oxygenates. Alkenes are produced industrially by petrochemical way mainly from crude oil, a non-renewable energy source. Conversion of ethanol to light olefins using an appropriate catalyst could replace the production of these key building blocks for the chemical industry. In this work, the focus is on the preparation and testing of heterogeneous catalysts in the transformation of ethanol to alkenes and acetaldehyde. In most cases, magnesia-based catalysts were used on a silica support during the experiment. Individual types of catalysts were compared in terms of yields of particular products, the effect of the feedstock load and that of calcination temperature of the catalyst on the catalytic activity are discussed. The highest ethylene yields (95 %) were achieved over an Mg-β-zeolite catalyst; the highest yield of 1,3-butadiene (29.1 %) was achieved in case of an Na/alumina catalyst; and the highest acetaldehyde yield (22.3 %) was achieved using a K-doped MgO/SiO2 catalyst.

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Stories with microorganisms…

Abstract

Microorganisms, usually invisible for us, accompany us always and everywhere. Often we do not realize how decisive its impact on our lives is, how much we use their presence, which of our troubles are the result of their actions, and also how surprising effects result from their activity. Microorganisms also very often play a decisive role in the development of societies, politics and history. One of the most spectacular interventions of micro-organisms in human history include the example of a false “oil fever” that exploded in Australia in the second half of the nineteenth century. It was even more significant to redirect Europe's history in the new direction as a result of the “black death” epidemic in the fourteenth century. Microorganisms have created social conditions for the transition to the next epoch - renaissance, which forms the basis of today's shape. Because of the microorganisms J.F. Kennedy could have been in the 1960 President of the United States of America and to direct her development in the new direction and to stop Khrushchev's expansion into the second hemisphere. Microorganisms, not leaders and generals, won battles and wars. It was Rikketsia prowazeki, not the genius of the opponents, that broke Napoleon's power in Europe. Microorganisms fight disease, improving quality of life and prolonging its period. They allowed to control rabies and numerous infectious diseases. In the economy for the cause of microorganisms, powerful monopolies fell. Bacteria were also used to protect civilians in Poland during World War II. There are many similar stories to tell, stories in which microorganisms play an essential role. But would these stories be about microorganisms only? Or perhaps about people who were fascinated by the microscopic world of microbes discovered his secrets, meaning and ... beauty.

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Isolation and characterization of hydrocarbon-degrading fungi from Ogbe-Ijoh oil creek, Warri, Delta State, Nigeria

Bioremediation, p. 592, Wiley - Interscience, New York 2006. [12]. A. Ikelegbe, The economy of conflict in the oil rich Niger Delta region of Nigeria, Journal of Third World Studies 43 (2005) 24 - 50. [13]. C. Obi, Globalized images of environmental security in Africa, Review of African Political Economy 83 (2000) 47 - 62. [14]. S. Fujita, Simple modified method for fungal slide preparation, Medical Mycology Journal 54 (2013) 141 - 146. [15]. M. Brandt, D. Warnock. Taxonomy and classification of fungi. In

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Functional Traits and Plasticity of Plants in Ecological Research and Education

.jstor.org/stable/2995565 . [25] Küppers M. Carbon relations and competition between woody species in a central European hedgerow. I. Photosynthetic characteristics. Oecologia. 1984;64:332-343. DOI: 10.1007/BF00379131. [26] Deregibus VA, Sanchez RA, Casal JJ. Effects of light quality on tiller production in Lolium spp. Plant Physiol. 1983;72:900-902. DOI: 10.1104/pp.72.3.900. [27] Poorter H, Van de Vijver CADM, Boot RGA, Lambers H. Growth and carbon economy of a fast-growing and a slow-growing grass species as dependent on nitrate supply. Plant Soil. 1995

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An active indirect solar system for food products drying

Refereed Journal of Engineering and Science 4(4): 29—35. Sormoli ME, Langrish TAG (2016) LWT — Food Science and Technology 72: 1—8. Srisittipokakun N, Kirdsiri K, Kaewkhao J (2012) Procedia Engineering 32: 839—846. Sunil V, Sharma A, Sharma N (2012) Procedia Engineering 38: 3260—3269. Tiris C, Tiris M, Dincer I (1996) Applied Thermal Engineering. 16: 183—187. Wang W, Li M, Hassanien RHE, Wang YF, Yang LW (2018) Applied Thermal Engineering 134: 310—321. Ward M, Jalal A (2011) GAIN Report AF-2011-10: 2011 Afghan Agricultural Economy

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Analysis and classification of physical and chemical methods of fuel activation

: 91563 C2, Ukraine, F02M27/00/ The Device For Magnetic Treatment Of Liquid Fuel “Eco.” S.M. Pryschepa - №200804930; declared 16.04.2008, published 10.08.2010, Bulletin №15). Retrieved from http://uapatents.com/5-91563-pristrijj-dlya-magnitno-obrobki-ridkogo-paliva-eko.html . [14]. Patent UA: 74187 C2, Ukraine, 7F02M27/04/ Device And System For Fuel Economy, Fuel System (Options) And The System For Reducing Emission During The Use Of The Device . D.A. Muller - №20021210144; declared 21.05.2001; published 15. 11. 2005, Bulletin №11). Retrieved from http

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