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•Biological treatment of PW by R. erythropolis occurred at 0-60 g/L salinity.•Stepwise adaptation strategy raised COD removal of PW and shortened treatment time.•After two days, ...synthetic and real PW, showed maximum COD removals of 97% and 52•GC-MS analysis proved 93% of TPH removal from synthetic PW by R. erythropolis.
Oilfield produced water (PW) is a mixture of different organic and inorganic compounds. The effects of discharging PW into the environment have lately become a major issue of environmental concern. This study aims to consider the capability of a gram-positive bacterium named Rhodococcus erythropolis PTCC 1767 in biological treatment of synthetic and real PWs. A stepwise adaptation strategy was applied for acclimation of the microorganism, by increasing chemical oxygen demand (COD) of the synthetic PW. The maximum COD removal efficiency was observed at 97% in PW with 600 mg/L COD. Also, by raising concentration of NaCl (up to 60 g/L), the stepwise adaptation strategy was performed for acclimated bacteria. The maximum COD removal efficiency occurred in the presence of 25 g/L NaCl. The results of total organic carbon (TOC) analysis revealed a removal efficiency of 85% and GC-MS analysis indicated a removal of 93% hydrocarbons (C14-C26). The adapted cells were then applied for treating the real PW in which a COD removal efficiency of 52% was achieved.
The study describes the development of serfdom, the Dózsa Uprising, which was caused by social conflicts and the limitation of serfdom and their legal consequences. A significant milestone was the ...Urbárium of 1767, followed by two other decisive boundary stones: the Revolution of 1848 and the Austro-Hungarian Compromise of 1867. The latter was also significant in the way that it paved the way for the Austro-Hungarian Empire (alongside Japan) to enter the First World War, in parallel with and in a similar way to the Meiji Restoration, which began in Japan in 1867-1868. The study outlines the relations between serfdom and the peasantry, not only from a legal-historical, but also from an economic and social-historical perspective.
Further probing the nature of FSR 1767 Bonatto, C.; Bica, E.; Ortolani, S. ...
Monthly notices of the Royal Astronomical Society,
08/2009, Letnik:
397, Številka:
2
Journal Article
Pathophysiological explanations for metamorphopsia associated with retinal pathologies generally focus on photoreceptor organization disruption. However, the retinal microarchitecture is complicated, ...and we hypothesize that other retinal cells may also be involved. Metamorphopsia has been widely studied in eyes with epiretinal membranes and we revisit the idea that Müller cell displacement causes retinal macropsia. A Pub Med query and related article search for the macula ultrastructure under normal and pathological conditions revealed an enormous amount of information, particularly ultrahigh definition optical coherence tomography and other retinal imaging modality studies. Findings of these imaging studies support our hypothesis that Müller cells, and not cone photoreceptors, are primarily responsible for macropsia in eyes with epiretinal membranes. More specifically, we conclude that displacement of Müller cell endfeet, and not photoreceptor cones, is a more likely the explanation for retinal macropsia associated with epiretinal membranes.
مقدمه: ریزموجوداتی که در شرایط کمبود مواد مغذی (به‌ویژه نیتروژن) و به‌علت توقف رشد، اقدام به ذخیره‌کردن چربی می‌کنند، روغن‌های میکروبی را تولید می‌کنند. باتوجه‌به ساختار اسید چرب، روغن‌های میکروبی ...کاربردهای صنعتی دارند. هدف اصلی پژوهش حاضر، ارزیابی تولید روغن تک‌یاخته از باکتری Rhodococcus erythropolis PTCC 1767با استفاده از منابع خام ارزانقیمت است که برای نخستینبار در ایران انجام میشود. مواد و روشها: در مطالعۀ حاضر از باکتری Rhodococcus erythropolis PTCC 1767، از آب پنیر، ساقۀ گندم، گلوگز و گلیسرول برای منابع کربنی و از عصارۀ مخمر برای منبع نیتروژنی استفادهو باکتری در محیط MSM کشت داده شد. تحلیل FTIR بهمنظور اثبات وجود گروههای کربنی، تحلیل GC برای شناسایی اسید چرب و رنگآمیزی با سودان سیاه و عکسبرداری با میکروسکوپ الکترونی عبوری برای مشاهدۀ گرانول چربی ذخیرهشده در سلول انجام شد. نتایج: بیشترین حجم تولید چربی در تمام منابع کربنی به آب پنیر با 22/23 درصد در زمان 96 ساعت مربوط بود و بیشترین حجم چربی با استفاده از منبع کربنی ساقۀ گندم برابر 20 درصد در زمان 72 ساعت تولید شد. بحث و نتیجهگیری: نتایج پژوهش حاضر نشان دادند سویۀ رودوکوکوس توانایی تبدیل زیستی منابع کربنی ارزانقیمت ساقۀ گندم و آب پنیر به روغن میکروبی را دارد و این امر میتواند بهشکل برنامهای برای فرایندهای زیستفناورانۀ دوستدار محیطزیست به کار گرفته شود.
Intensive E region ionization extending up to 140 km altitude and lasting for several hours was observed with the European Incoherent Scatter (EISCAT) UHF radar during the 2002 Leonids meteor shower ...maximum. The level of global geomagnetic disturbance as well as the local geomagnetic and auroral activity in northern Scandinavia were low during the event. Thus, the ionization cannot be explained by intensive precipitation. The layer was 30–40 km thick, so it cannot be classified as a sporadic E layer which are typically just a few kilometers wide. Incoherent scatter radars have not to date reported any notable meteor shower‐related increases in the average background ionization. The 2002 Leonids storm flux, however, was so high that it might have been able to induce such an event. The Chemical Ablation Model is used to estimate deposition rates of individual meteors. The resulting electron production, arising from hyperthermal collisions of ablated atoms with atmospheric molecules, is related to the predicted Leonid flux values and observed ionization on 19 November 2002. The EISCAT Svalbard Radar (ESR) located at some 1000 km north of the UHF site did not observe any excess ionization during the same period. The high‐latitude electrodynamic conditions recorded by the SuperDARN radar network show that the ESR was within a strongly drifting convection cell continuously fed by fresh plasma while the UHF radar was outside the polar convection region maintaining the ionization.
Key PointsMeteor storms can induce strong enhanced E region ionization
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