Bacillariophyta of the Yavorivsky National Park, Broadleaf Forest Zone of Ukraine, including Сaloneis albus-columba, sp. nov.

Diatoms (Bacillariophyta) are one of the major biological components in all kinds of aquatic ecosystems both in freshwater and marine ones. The nature reserve fund of Ukraine includes 52 national parks, in the vast majority of which Bacillariophyta have not been studied. This investigation presents first data on the diatoms in Yavorivsky National Park located in Lviv region. The material consists of the epiphytic samples of microalgae that were collected from different substrates in aquatic ecosystems of the Yavorivsky National Park in 2014. In the hydrotopes of the park 180 diatom species from 56 genera were found, among them Achnanthidium catenatum (Bily & Marvan) Lange-Bertalot, Cymbopleura apiculata Krammer, Fallacia sublucidula (Hustedt) D. G. Mann in Round, Crawford & Mann, Gomphonema lagenula Kützing, G. supersedens Reichardt, G. pseudopusillum Reichardt, Paraplaconeis minor (Grunow) Lange-Bertalot, Placoneis constans (Hustedt) E. J. Cox, Psammothidium bioretii (Germain) Bukhtiyarova & Round, P. vernadskyi Bukhtiyarova et Stanislavskaya, Sellaphora gracillima Zidarova, Kopalová & Van de Vijver, S. insolita (Manguin) Hamilton et Antoniades, Stauroneis fluminopsis Van de Vijver et Lange-Bertalot were recorded for the first time in Ukraine. Besides that, Amphora hemicycla Stoermer & J. J. Yang and Sellaphora bacilloides (Hustedt) Levkov, Krstic & Nakov also were new findings in the country from the Broadleaf Forest Zone of Ukraine. Many species rare in the world flora and in Ukraine were found. A new diatom species Сaloneis albus-columba Bukhtiyarova, sp. nov., was described from the pond in stationary recreation area Kozulka. This new species possesses strongly three-undulate valves with three rhombic segments, which in morphology is most similar to Caloneis lamella Zakrzewski, however it differs from it by having rhombic distal valve segments instead of oval ones as well as noticeably smaller width of the central valve segment. The morphology of other similar species is discussed. For proper description of the new species new definitions for the raphe system morphology were grounded on functional morphology of the diatom frustule. New combinations Iconella alaskaensis (Foged) Bukhtiyarova, comb. et stat. nov., Iconella baltica (Schumann) Bukhtiyarova, comb. nov., Iconella brebissonii (Krammer & Lange-Bertalot) Bukhtiyarova, comb. nov., Iconella brightwellii (W. Smith) Bukhtiyarova, comb. nov., Iconella constricta (Grunow) Bukhtiyarova, comb. et stat. nov., Iconella didyma (Kützing) Bukhtiyarova, comb. nov. and Iconella elegans (Ehrenberg) Bukhtiyarova, comb. nov. were formally proposed. The lectotype for Eunotia glacialis F. Meister was designated here. Illustrations with light and scanning electron microscopy are presented. A primary inventory of Bacillariophyta and their subsequent study on protected territories in Ukraine is still an important task in the context of preservation of biodiversity of the country

Fe2O3 supported on hollow micro/mesospheres silica for the catalytic partial oxidation of H2S to sulfur

[EN] A family of Fe-based catalysts supported hollow silica mesospheres has been synthesized and tested in the catalytic partial oxidation of H2S to elemental sulfur at 170.180 degrees C, atmospheric pressure and under 300 min of time-on-stream. The characterization of the synthesized catalysts by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance UV-vis spectra (DRS), H-2-termoprogrammed reduction (H-2-TPR), N-2 adsorption-desorption at -196 degrees C and X-ray photoelectron spectroscopy (XPS) reveals the formation of a catalytic system with high micro- and mesoporosity with high dispersion of the Fe2O3 species. The catalytic results reported high activity in the selective oxidation of H2S, reaching a highest conversion value close to 94% with a selectivity towards elemental sulfur of 98% after 300 min of time on stream (TOS) at 180 degrees C for the HMS-10Fe catalyst. The comparison of Fe-containing HMS (10 wt% of iron loading) with other SiO2-based supports, as a fumed silica (Cab-osil) or a mesoporous silica (SBA-15), presents different H2S conversion values, following the next trend: HMS-10Fe > SBA-10Fe > Cab-10Fe. These results suggest that the use of a support with a narrow pore tend to facilitate the iron dispersion favoring higher conversion rates.The authors wish to acknowledge the financial support provided by the Ministry of Economy and Competitiveness (Spain) (MINECO) CTQ2015-68951-C1-3R y CTQ2015-68951-C3-3R, Junta de Andalucia (Spain) P12-RNM 1565 and FEDER funds. In addition, the authors also thank Fundacao Cearense de Apoio ao Desenvolvimento Cientifico e Tecnologico (FUNCAP) by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) - Processo: PDSE 99999.002602/2014-08.Cecilia, J.; Soriano Rodríguez, MD.; Marques Correia, L.; Rodríguez-Castellón, E.; López Nieto, JM.; Silveira Vieira, R. (2020). Fe2O3 supported on hollow micro/mesospheres silica for the catalytic partial oxidation of H2S to sulfur. Microporous and Mesoporous Materials. 294:1-10. https://doi.org/10.1016/j.micromeso.2019.109875S11029

Comparative Study of Batch and Continuous Flow Reactors in Selective Hydrogenation of Functional Groups in Organic Compounds: What Is More Effective?

Many research papers describe selective hydrogenation of functional groups, such as nitro groups, carbonyl groups, or unsaturated carbon bonds to obtain fine chemicals or precursors of pharmaceuticals. Quite often, the catalyst performance is investigated in batch or continuous flow reactors without finding advantages and disadvantages of this or that regime. At the same time, the transition from batch processes to continuous flow occurs on the industrial scale. However, the batch process can be preferable for some reactions, in spite of its drawbacks. This review article aims to identify all publications that consider selective hydrogenation of functional groups in organic compounds, both in batch and continuous flow reactors, at the same reaction conditions that allow making conclusions about the benefits of one of the regimes in a particular case