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Effect of Hydrocarbon Contamination on the Microbial Diversity of Freshwater Sediments Within Akwa Ibom State, Nigeria
Mfoniso Uko,
Ime Udotong,
Utibe Ofon,
Senyene Umana,
Nsikak Abraham
Issue:
Volume 4, Issue 2, December 2020
Pages:
32-38
Received:
15 January 2020
Accepted:
4 February 2020
Published:
8 June 2020
Abstract: A microbial composition study of sediments of contaminated (CWS) and uncontaminated (UWS) lentic ecosystems within Akwa Ibom State was carried out by analyzing the small-subunit rRNA genes to determine the effect of hydrocarbon contamination on its microbial composition and diversity. Analysis of the V4 region of the community DNA from both sediments revealed the presence of bacteria, archaea and microalgae. Bacterial sequences outnumbered archaea and microalgae. Abundance of Proteobacteria, Betaproteobacteria, Burholderiales, Alcaligenaceae, and Achrombacter were observed in the CWS and Actinobacteria, Actinomycetales, Bacillaceae, and Bacillus in the UWS. Crenarchaeota and Euryarchaeota were also observed to be present in both sediments. The genus Achromobacter and Bacillus dominated in the CWS and UWS, respectively. Uncultured bacterium with the accession number DQ404672.1 and AY917600.1 led at the species levels. Achromobacter sp.-AM232721.1 outnumbered the other species in the CWS such as Kitasatospora sp.-AF131379.1, Mycobacterium celatum-AF547908.1, Paenibacillus phyllosphaerae-NR_043008.1, Cystobacter fuscus-M94276.1, Planosporangium flavigriseum-NR_042508.1, etc. In the UWS, the dominant species was Bacillus sp.-AJ316313.1. Microalgae, Chlorella sp. and Chlorella vulgaris were also detected in both ecosystems. Diverse and distinct diversity of bacteria, archaea and microalgae are present in the sediments and only a few of them have cultured counterpart. The variation in the microbial communities from the two sites has revealed the impact of contaminants especially hydrocarbons on the microbial diversity in lentic ecosystems.
Abstract: A microbial composition study of sediments of contaminated (CWS) and uncontaminated (UWS) lentic ecosystems within Akwa Ibom State was carried out by analyzing the small-subunit rRNA genes to determine the effect of hydrocarbon contamination on its microbial composition and diversity. Analysis of the V4 region of the community DNA from both sedimen...
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Synthesis, Characterization and Reactivity of Nitrosyl Ruthenium Complexes with the Non-stereoidal Anti-inflammatory Diflunisal
Ernani Lacerda de Oliveira Neto,
Juliana Guerreiro Cezar,
Fabio Gorzoni Doro,
Jose Roque Mota Carvalho,
Kleber Queiroz Ferreira
Issue:
Volume 4, Issue 2, December 2020
Pages:
39-46
Received:
29 August 2019
Accepted:
2 September 2019
Published:
9 June 2020
Abstract: The Na2[Ru(NO)Cl3 (df)] (I) and cis-[Ru(NO)(df)(cyclen)]Cl2 (II) complexes (df=diflunisal (5-(2,4-difluorophenyl)-2-hydroxybenzoic acid, cyclen=1, 4, 7, 10-tetraazacyclododecane) have been synthesized and characterized by elemental analysis, electronic (UV-Vis) and vibrational (FTIR) spectroscopic techniques. FTIR data suggests different modes of coordination of the ligand diflunisal in these complexes, i.e., coordinated in the bidentate form in the compound I and in the monodentate form in the compound II, and that df is coordinated to ruthenium by carboxylate group in a monodentate mode for both complexes. The FTIR spectra also display v(NO) at 1880 cm-1 and 1892 cm-1 for I and II, respectively, indicating a nitrosonium (NO+) character. Electronic spectra suggest that df is coordinated to the metal center in both complexes in catecholate form. Detailed electrochemical studies showed that complexes I and II display {RuNO}6/7 process at -420 mV and at -400 mV (vs. Ag/AgCl) respectively, and df ligand is oxidized at 1120 mV and at 770 mV, respectively. Controlled potential electrolysis at -750 mV or chemical reduction with Zn(Hg) amalgam results in NO release from both complexes.
Abstract: The Na2[Ru(NO)Cl3 (df)] (I) and cis-[Ru(NO)(df)(cyclen)]Cl2 (II) complexes (df=diflunisal (5-(2,4-difluorophenyl)-2-hydroxybenzoic acid, cyclen=1, 4, 7, 10-tetraazacyclododecane) have been synthesized and characterized by elemental analysis, electronic (UV-Vis) and vibrational (FTIR) spectroscopic techniques. FTIR data suggests different modes of c...
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Attaining High Standards of Safety and Health Through Sustainable Development of Dimensional Limestone (Kotah Stone): A Success Story
Er Satish Chand Agarwal Fie
Issue:
Volume 4, Issue 2, December 2020
Pages:
47-52
Received:
2 January 2020
Accepted:
4 June 2020
Published:
16 June 2020
Abstract: The State of Rajasthan has been gifted with unique mineral reserves of dimensional limestone widely known as Kotah Stone spreading over an area of over 55 sq km. The conventional manual mining of Kotah Stone, has been going on since 1945 but all manual. It has not only degraded the environment severally but also proved to be unsafe. Major part of human efforts has been wasted in non-productive jobs causing excessive fatigue and mental stress, inflicting excessive injuries to eye, leg, foot, arm, fingers and spinal cord. Some time in 1992 industry stood on economical threshold when it felt necessary either to develop an appropriate mining technology or close down all mining activities. A responsible mining technology was innovated by the author based on concept of in-situ cutting & sizing prior to splitting. The process has eliminated many hazardous manual process resulting in sharp reduction in accidents human fatigue and stress. Frequency of accident has reduce to 1/6th: Man days lost per lac sqft of production has also reduce from 36.6 to 13 only. Major part of non-productive effort has been converted in productive increasing productivity by 3.5 times. It has also created cool and clean working environment which keeps worker calm and tolerant and alert against any danger. The technology proved to be blessings for all stake holders. The innovation has fulfilled objectives defined for Responsible mining such as respect for human rights and aspirations of affected community, providing safe, healthy, and respectful workplace, mininimising harm to environment and leaving positive legacy.
Abstract: The State of Rajasthan has been gifted with unique mineral reserves of dimensional limestone widely known as Kotah Stone spreading over an area of over 55 sq km. The conventional manual mining of Kotah Stone, has been going on since 1945 but all manual. It has not only degraded the environment severally but also proved to be unsafe. Major part of h...
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The Design of Shell-and-tube Heat Exchanger in the Project of the Coal Bed Methane Electrical Power Generation
Issue:
Volume 4, Issue 2, December 2020
Pages:
53-59
Received:
24 April 2020
Accepted:
18 May 2020
Published:
23 July 2020
Abstract: Coal-bed-methane (CBD) electrical power generation is an active and effective measure to reduce emissions of greenhouse gases. Using shell-and-tube heat exchangers to reduce the water content of pipeline gas can improve the efficiency of the generator set. Designing heat exchanger by ASPEN EDR software can save a lot of manual calculation process, so as to improve the efficiency of the heat exchanger designer. The general method of designing and verifying shell-and-tube heat exchanger by EDR ASPEN software is described in this article by the example of the local process of low concentration gas power generation project. Because of the heat flux medium is low concentration coal bed methane with high explosion risk, anti-explosion measures must be taken to ensure safety beyond the requirements of normal heat exchangers of heat transfer, pressure drop.
Abstract: Coal-bed-methane (CBD) electrical power generation is an active and effective measure to reduce emissions of greenhouse gases. Using shell-and-tube heat exchangers to reduce the water content of pipeline gas can improve the efficiency of the generator set. Designing heat exchanger by ASPEN EDR software can save a lot of manual calculation process, ...
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Decontamination of Toxic Volatile Organic Compounds in Charcoal Processed from Erythrophleum guineense (Sassy Wood)
John Stephen Gushit,
Ester Habila
Issue:
Volume 4, Issue 2, December 2020
Pages:
60-65
Received:
30 June 2020
Accepted:
17 July 2020
Published:
4 August 2020
Abstract: The work aimed at decontaminating potentially toxic compounds found in the charcoal sample, started with collecting the sample of charcoal processed from Erythrophleum guineense (Sassy wood) established in an earlier work to be emitting toxic compounds. The sample was subjected to combustion in a chamber and the volatiles organic compounds (VOCs), formaldehyde (HCHO) and other air quality parameters detected from the hot smoke emitted using the Air Pollutant Detector (Air Master). The VOCs and HCHO average concentration of 2.98mg/m3 and 1.27mg/m3 respectively were detected in the sample, giving indication of extremely high concentration beyond standard permissible limits. The decontaminants which includes; CaO, NaCl, KOH, NaCl/CaO (1:1) and Al2O3 were prepared by dissolving pulverized portion of each in a small amount of distilled water and diluted with purified dual-purpose kerosene (DPK), after which each solution was uniformly sprayed on the pre-weighed charcoal in the combustion chamber. On applying the prepared decontaminants: CaO, NaCl, KOH, NaCl/CaO and Al2O3 on the charcoal, the VOCs concentration of 0.32mg/m3, 0.60mg/m3, 0.61 mg/m3, 1.11 mg/m3 and 2.88mg/m3 respectively were detected, which showed significant reduction in the concentration of the VOCs emitted that is far below the WHO limits for short term exposure of 0.1 mg/ m3, indicating that using the decontaminants is required if such charcoals must continue to be used. The VOCs were characterized in all the samples after they were adsorbed, desorbed, extracted, purified, concentrated and finally detected using the Gas chromatography Mass Spectrometry (GC-MS). The VOCs detected are; Octadecanoic, n-hexadecenoic acid, levomenthol acid and cyclobutanol acid widely reported to be toxic. Therefore, the work recommends that charcoal fires should not be ignited and used in enclosures, and appropriate Government regulatory agencies should create awareness on the need to avoid the use of Erythrophleum guineense (sassy wood) charcoal. If it must be used, decontaminant like CaO prepared from this work should be used since it is a cheap and accessible waste material found in auto mechanic garages indiscriminately discarded by gas welders.
Abstract: The work aimed at decontaminating potentially toxic compounds found in the charcoal sample, started with collecting the sample of charcoal processed from Erythrophleum guineense (Sassy wood) established in an earlier work to be emitting toxic compounds. The sample was subjected to combustion in a chamber and the volatiles organic compounds (VOCs), ...
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