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71.
72.
The biochar is an important carbon-rich product that is generated from biomass sources through pyrolysis. Biochar (charcoal) can be both used directly as a potential source of solid biofuels and as soil amendments for barren lands. The aim of this study was investigate influence of pyrolysis temperature on the physicochemical properties and structure of biochar. The biochars were produced by pyrolysis of rapeseed (Brassica napus L.) using a fixed-bed reactor at different pyrolysis temperatures (400–700°C). The produced biochars were characterized by proximate and elemental analysis, Brunauer–Emmett–Teller (BET) surface area, particle size distributions, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy. The results showed that both chemical and surface properties of the biochars were significantly affected by the pyrolysis temperature. Aromatic hydrocarbons, hydroxyl and carbonyl compounds were the majority components of the biochar. The biochar obtained at 700°C had a high fixed carbon content (66.16%) as well as a high heating value, and therefore it could be used as solid fuel, precursor in the activated carbons manufacture (specific surface area until 25.38 m2 g?1), or to obtain category-A briquettes. 相似文献
73.
Chromosomal analysis of more than 500 larval black flies from 19 sites in Armenia and Turkey revealed five taxa in the Prosimulium hirtipes group: Prosimulium frontatum Terteryan, Prosimulium rachiliense Djafarov cytoform ‘A,’ P. rachiliense Djafarov cytoform ‘B,’ Prosimulium tomosvaryi (Enderlein), and a new species of Prosimulium. To associate the names rufipes (Meigen) and tomosvaryi with cytological entities, larvae from the respective type localities in Germany were characterized chromosomally. Prosimulium frontatum is restricted to the Caucasus Mountains where studied populations have five unique inversions. It is most closely related to cytoforms ‘A’ and ‘B’ of P. rachiliense, the three taxa sharing one unique inversion. The two cytoforms of P. rachiliense are separated by about 1200 km, obscuring decisions about their reproductive isolation. The names rachiliense and possibly pronevitschae Rubtsov apply to cytoform ‘A’ in Armenia, whereas the name fulvipes (Edwards) might apply to cytoform ‘B’ in Turkey and to material formerly identified in Turkey as P. rufipes. Populations of P. tomosvaryi in Armenia are chromosomally distinct from previously studied populations in Europe and Morocco, although tied to European and Turkish populations by a shared X‐linked inversion. We conservatively view Armenian, European, and Turkish populations of P. tomosvaryi as a single, polymorphic species. A new species, chromosomally related to P. hirtipes (Fries) and P. tomosvaryi by two uniquely shared inversions, was discovered in Turkey. © 2014 The Linnean Society of London 相似文献
74.
The effect of astaxanthin and cadmium on rat erythrocyte G6PD, 6PGD,GR, and TrxR enzymes activities in vivo and on rat erythrocyte 6PGD enzyme activity in vitro 下载免费PDF全文
Mahire Bayramoğlu Akkoyun A. Şükrü Bengü Yusuf Temel H. Turan Akkoyun Suat Ekin Mehmet Ciftci 《Journal of biochemical and molecular toxicology》2018,32(8)
In this study, the effects of astaxanthin (AST) that belongs to carotenoid family and cadmium (Cd), which is an important heavy metal, on rat erythrocyte G6PD, 6PGD, GR, and TrxR enzyme activities in vivo and on rat erythrocyte 6PGD enzyme activity in vitro were studied. In in vitro studies, 6PGD enzyme was purified from rat erythrocytes with 2′,5′‐ADP Sepharose4B affinity chromatography. Results showed inhibition of enzyme by Cd at IC50; 346.5 μM value and increase of 6PGD enzyme activity by AST. In vivo studies showed an increase in G6PD, 6PGD, and GR enzyme activities (P ? 0.05) and no chance in TrxR enzyme activity by AST. Cd ion inhibited G6PD, 6PGD, and GR enzyme activities (P ? 0.05) and also decreased TrxR enzyme activity (P ? 0.05). AST + Cd group G6PD enzyme activity was statistically low compared with control group (P ? 0.05). 6PGD and TrxR enzyme activities decreased without statistical significance (P ? 0.05); however, GR enzyme activity increased statistically significantly (P ? 0.05). 相似文献
75.
76.
Ştefan Ţălu Ilya A. Morozov Dinara Sobola Pavel Škarvada 《Bulletin of mathematical biology》2018,80(11):2856-2870
A lot of insect families have physical structures created by evolution for coloration. These structures are a source of ideas for new bio-inspired materials. The aim of this study was to quantitatively characterize the micromorphology of butterfly wings scales using atomic force microscopy and multifractal analysis. Two types of butterflies, Euploea mulciber (“striped blue crow”) and Morpho didius (“giant blue morpho”), were studied. The three-dimensional (3D) surface texture of the butterfly wings scales was investigated focusing on two areas: where the perceived colors strongly depend on and where they do not depend on the viewing angle. The results highlight a correlation between the surface coloration and 3D surface microtexture of butterfly wings scales. 相似文献
77.
Production of (R)‐1‐(1,3‐benzodioxol‐5‐yl)ethanol in high enantiomeric purity by Lactobacillus paracasei BD101 下载免费PDF全文
Engin Şahin 《Chirality》2018,30(2):189-194
Piperonyl ring is found in a number of naturally occurring compounds and possesses enormous biological activities. There are many studies in the literature with compounds containing a piperonyl ring, but there are very few studies on the synthesis of chiral piperonyl carbinol. The objective of this study was to determine the microbial reduction ability of bacterial strains and to reveal the effects of different physicochemical parameters on this reduction ability. A total of 15 bacterial isolates were screened for their ability to reduce 1‐(benzo[d][1,3]dioxol‐5‐yl) ethanone 1 to its corresponding alcohol. Among these isolates Lactobacillus paracasei BD101 was found to be the most successful biocatalyst to reduce the ketone containing piperonyl ring to the corresponding alcohol. The reaction conditions were systematically optimized for the reducing agent L paracasei BD101, which showed high enantioselectivity and conversion for the bioreduction. The preparative scale study was performed, and a total of 3.72 g of (R)‐1‐(1,3‐benzodioxol‐5‐yl) ethanol in high enantiomeric form (>99% enantiomeric excess) was produced in a mild, cheap, and environment‐friendly process. This study demonstrates that L paracasei BD101 can be used as a biocatalyst to obtain chiral carbinol with excellent yield and selectivity. 相似文献
78.
Identifying critical migratory bottlenecks and high‐use areas for an endangered migratory soaring bird across three continents 下载免费PDF全文
Evan R. Buechley Steffen Oppel William S. Beatty Stoyan C. Nikolov Vladimir Dobrev Volen Arkumarev Victoria Saravia Clementine Bougain Anastasios Bounas Elzbieta Kret Theodora Skartsi Lale Aktay Karen Aghababyan Ethan Frehner Çağan H. Şekercioğlu 《Journal of avian biology》2018,49(7)
Migrant birds face a number of threats throughout their annual cycle, including persecution, collision with energy infrastructure, and habitat and climate change. A key challenge for the conservation of migrants is the identification of important habitat, including migratory concentration areas, because species survival rates may be determined by events in geographically very limited areas. Remote‐tracking technology is facilitating the identification of such critical habitat, although the strategic identification of important sites and incorporation of such knowledge in conservation planning remains limited. We tracked 45 individuals of an endangered, soaring migrant (Egyptian vulture Neophron percnopterus), over 75 complete migrations that traversed three continents along the Red Sea Flyway. We summarize and contextualize migration statistics by season and age class, including migration start, midpoint, and end dates, as well as linear and cumulative migration distance, migration duration and speed, and route straightness. Then, using dynamic Brownian bridge movement models, we quantified space use to identify the most important migratory bottlenecks and high‐use areas on the flyway. These areas each accounted for < 5% of the overall movement range of the tracked birds, yet > 20% of all tracks passed through bottlenecks, and > 50% of the overall vulture time spent on migration fell within high‐use areas. The most important sites were located at the southeastern Red Sea coast and Bab‐el‐Mandeb Strait (Saudi Arabia, Yemen, Djibouti), the Suez Canal zone (Egypt), and the Gulf of Iskenderun (Turkey). Discouragingly however, none of the area within the major migratory bottlenecks was protected and < 13% of the high‐use areas were protected. This demonstrates a very concerning gap in the protected area network for migratory soaring birds along the Red Sea Flyway. Because reducing threats at migratory concentrations can be a very efficient approach to protect populations, our work provides clear guidelines where conservation investment is urgently needed to benefit as many as 35 migratory soaring‐bird species that regularly use the Red Sea Flyway. 相似文献
79.
An integrative anatomical,morphological, micromorphological and molecular approach to Turkish epidendroid and orchidoid species (Orchidaceae) 下载免费PDF全文
Gülcan Şenel Şenay Süngü Şeker Mustafa Kemal Akbulut Öznur Ergen Akçin 《Nordic Journal of Botany》2018,36(7)
We aimed to describe and analyse the morphological, anatomical and micromorphological traits of 36 Turkish orchids representing 12 genera (e.g. Anacamptis, Cephalanthera, Dactylorhiza, Orchis, Serapias) in detail and analyse their usability for solving phylogenetic and taxonomic issues. We applied UPGMA cluster analysis to anatomical, morphological and micromorphological characters such as root tubers, leaf and flower structures, pit, sclerenchymatic sheath, vascular bundle shape, crystal and starch, exodermis and endodermis structure, stomata type, bulliform cells in roots, shoots and leaves, surface structures like papillae, hairs and ornamentation on flower parts, leaves, fruits and seeds. Furthermore, in a phylogenetic framework, we analysed nuclear ribosomal ITS diversity in the same orchid species belonging, and in a combined Bayesian phylogenetic analysis based on anatomical, morphological, micromorphogical and ITS data we confirmed the usefulness of multiple data sets for effectively assessing taxonomically critical orchids. In the combined analysis, all genera were resolved as monophyletic with topologies congruent with recently published more thorough molecular phylogenetic reconstructions, while the trees obtained by seprately analysing the ITS and the anatomical, morphological, micromorphogical data were less resolved and partly inconclusive. 相似文献
80.
Mallomonas is the largest genus of the Synurophyceae (chrysophytes) and includes more than 120 species. Most of them are cosmopolitan,
living in freshwater habitats. The Rumanian taxa occur usually in spring or early summer at water temperatures ranging between
4 ° and 10 °C. They are most frequent in neutral or slightly acid, clear-watered, aquatic habitats of various types. However,
Mallomonas paludosa Fott appears mostly in brown watered peatbog pools of low mineral contents, having a particular geographical area, with its
southernmost limit in the Rumanian Eastern Carpathians. Its distribution, like that of other boreal elements, is strictly
connected with the occurrence of genuine ombrogenic Sphagnum-bogs, which have their southern limit also in Romania. The other two species dealt with — M. cyathellata Wujek & Asmund and M. portae-ferreae Péterfi & Asmund —, occurring in circumneutral or moderately alkaline waters of eutrophic character, are apparently warm
water forms, mostly distributed in tropical, subtropical or mediterranean zones. The Rumanian localities (in the Danube Delta
and at Eşelniţa near the Danube, up stream Drobeta Turnu-Severin) might be the northern limits of M. portae-ferreae in Eastern Europe. The Danube Delta is the only locality of M. cyathellata in Europe, and its northernmost occurrence as well. The occurrence of both species in Rumania is presumably due to migratory
waterfowl. 相似文献