99 research outputs found

    Chapter 11 - Sequestration of carbon dioxide into petroleum reservoir for enhanced oil and gas recovery

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    This chapter presents a detailed and important study of the effectiveness of enhanced oil/gas technology in an unconventional petroleum reservoir. To meet the challenges of ever-increasing amount of greenhouse gas emissions and the long-term need for energy supplies, enhanced oil/gas recovery (EOR/EGR) techniques, which are the most appropriate approach to be used for both scientific and industrial benefits, are systematically explored. Owing to the decline of fossil energy, the global demand for energy could not be fulfilled by oil and natural gas. Generally, EOR/EGR is used to maintain critically regulated pore strength where gases (e.g., CO2, CO, N2, etc.) are injected into the petroleum reservoir through a vertical well. These techniques for oil recovery are more efficient, while primary and secondary techniques for oil recovery are inconvenient. The use of CO2 storage or EOR/EGR in oil or gas reserves is more complicated due to their significant variations in porosity and permeability. This chapter concludes with an important debate on the prospects and problems of CO2 sequestration in oil and gas reservoirs for EOR/EGR and future avenues for study

    Catalytic gasification of empty palm fruit bunches using charcoal and bismuth oxide for syngas production

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    The purpose of this research is to evaluate the intent of empty fruit bunches of palm oil (EFBpalm oil) to catalytic gasification of wood produced charcoal (Woodcharcoal) in order to notify the large-scale application of Woodcharcoal as a possible gasification feedstock. In this study, co-catalyst of bismuth oxide (Bi2O3) was also used to obtain syngas. The raw samples were characterized by proximate and ultimate analyses, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses. The produced syngas was analyzed by online portable gas analyzer and gas chromatography-thermal conductivity detector (GC-TCD). The syngas composition of H2 increased from 3.91 to 4.70% (increased 20.20%), CO increased from 5.73 to 6.30% (increased 10.53%), whereas CO2 decreased from 20.60 to 12.67% (decreased 38.50%) and CH4 concentration increased insignificantly from 0.35 to 0.37% (increased 5.7%) which was happened due to the use of WoodCharcoal and Bi2O3 with EFBpalm oil during gasification. According to the findings, carbon is abundant in WoodCharcoal, which may considerably boost the gasification reactivity with Bi2O3. The yield of syngas (H2 and CO) increased when WoodCharcoal and Bi2O3 were used instead of single EFBppo gasification, indicating that catalyst (WoodCharcoal) and co-catalyst (Bi2O3) have a high potential for thermal decomposition and dehydrogenation of volatile matter. Therefore, catalytic gasification of empty palm fruit bunches will be the prospective energy sources for the production of syngas with the utilization of WoodCharcoal and Bi2O3

    The Importance of Research on the Origin of SARS-CoV-2

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    The origin of the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) virus causing the COVID-19 pandemic has not yet been fully determined. Despite the consensus about the SARS-CoV-2 origin from bat CoV RaTG13, discrepancy to host tropism to other human Coronaviruses exist. SARS-CoV-2 also possesses some differences in its S protein receptor-binding domain, glycan-binding N-terminal domain and the surface of the sialic acid-binding domain. Despite similarities based on cryo-EM and biochemical studies, the SARS-CoV-2 shows higher stability and binding affinity to the ACE2 receptor. The SARS-CoV-2 does not appear to present a mutational “hot spot” as only the D614G mutation has been identified from clinical isolates. As laboratory manipulation is highly unlikely for the origin of SARS-CoV-2, the current possibilities comprise either natural selection in animal host before zoonotic transfer or natural selection in humans following zoonotic transfer. In the former case, despite SARS-CoV-2 and bat RaTG13 showing 96% identity some pangolin Coronaviruses exhibit very high similarity to particularly the receptor-binding domain of SARS-CoV-2. In the latter case, it can be hypothesized that the SARS-CoV-2 genome has adapted during human-to-human transmission and based on available data, the isolated SARS-CoV-2 genomes derive from a common origin. Before the origin of SARS-CoV-2 can be confirmed additional research is required

    Periodically aperiodic pattern of SARS-CoV-2 mutations underpins the uncertainty of its origin and evolution

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    Various lineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have contributed to prolongation of the coronavirus disease 2019 (COVID-19) pandemic. Several non-synonymous mutations in SARS-CoV-2 proteins have generated multiple SARS-CoV-2 variants. In our previous report, we have shown an evenly uneven distribution of unique protein variants of SARS-CoV-2 is geo-location or demography-specific. However, the correlation between the demographic transmutability of the SARS-CoV-2 infection and mutations in various proteins remains unknown due to hidden symmetry/asymmetry in the occurrence of mutations. This study tracked how these mutations are emerging in SARS-CoV-2 proteins in six model countries and globally. In a geo-location, considering the mutations having a frequency of detection of at least five hundred in each SARS-CoV-2 protein; we studied the country-wise percentage of invariant residues. Our data revealed that since October 2020, highly frequent mutations in SARS-CoV-2 have been observed mostly in the Open Reading Frames (ORF) 7b and ORF8, worldwide. No such highly frequent mutations in any of the SARS-CoV-2 proteins were found in the UK, India, and Brazil, which does not correlate with the degree of transmissibility of the virus in India and Brazil. However, we have found a signature that SARS-CoV-2 proteins were evolving at a higher rate, and considering global data, mutations are detected in the majority of the available amino acid locations. Fractal analysis of each protein's normalized factor time series showed a periodically aperiodic emergence of dominant variants for SARS-CoV-2 protein mutations across different countries. It was noticed that certain high-frequency variants have emerged in the last couple of months, and thus the emerging SARS-CoV-2 strains are expected to contain prevalent mutations in ORF3a, membrane, and ORF8 proteins. In contrast to other beta-coronaviruses, SARS-CoV-2 variants have rapidly emerged based on demographically dependent mutations. Characterization of the periodically aperiodic nature of the demographic spread of SARS-CoV-2 variants in various countries can contribute to the identification of the origin of SARS-CoV-2

    The Palestinian Terrestrial Vertebrate Fauna Preserved at the Biology Exhibitions of the Universities of the Gaza Strip

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    The Gaza Strip (365 km2 ) of Palestine (27,000 km2 ) is home to a wealth of terrestrial vertebrate fauna. Some of these faunistic species find their ways to preservation at the local universities. Hence, the current study comes to document the Palestinian terrestrial vertebrate fauna acquired by the biology exhibitions (BEs) of Al-Azhar University, Islamic University of Gaza and Al-Aqsa University that are located at the Gaza City of the Gaza Strip. The amphibians, reptiles, birds and mammals preserved at BEs of the universities in question were surveyed and scientifically classified during a three-month period extending from January to March, 2012. The study showed that all BEs of local universities are underdeveloped, lacking attention and suffer from specimen scarcity and good preservation. The BE at Al-Azhar University is the best in the arrangement and preservation of bird specimens. A total number of 200 specimens belonging to 54 terrestrial vertebrate fauna species, 39 families and 17 orders was recorded at BEs. Reptiles constituted 40.7% of the total species recorded, followed by birds (38.9%), mammals (14.8%) and amphibians (5.6%). The Islamic University of Gaza was considered the best in terms of the number of preserved species (39.8%), followed by Al-Azhar University (36.3%) and Al-Aqsa University (23.9%). The Common Toad (Bufo viridis) was the most preserved among the amphibian species recorded. Squamata was the biggest reptilian order, comprising 20 species (8 lizards and 12 snakes), with the Syrian Black Snake (Coluber jugularis asianus) was the commonest. The Palestine Viper (Vipera palaestinae) is endemic to Palestine and most venomous and dangerous to human health. The Great White Pelican (Pelecanus onocrotalus) was the largest Palestinian bird preserved at BE of Al-Azhar University. The Egyptian Mongoose (Herpestes ichneumon) and the Common Badger (Meles meles) were the biggest mammalian specimens preserved, while the Palestine Mole-rat (Spalax leucodon ehrenbergi) was the only Palestine endemic species encountered among the preserved mammals. Finally, the improvement of BEs of local universities and the construction of a Central Museum of Natural History is highly recommended in order to change the Palestinians’ attitudes toward a sustainable ecological conservation in the Gaza Strip

    Carbon-Based Nanomaterials: Promising Antiviral Agents to Combat COVID-19 in the Microbial-Resistant Era

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    Therapeutic options for the highly pathogenic human severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the current pandemic coronavirus disease (COVID-19) are urgently needed. COVID-19 is associated with viral pneumonia and acute respiratory distress syndrome causing significant morbidity and mortality. The proposed treatments for COVID-19 have shown little or no effect in the clinic so far. Additionally, bacterial and fungal pathogens contribute to the SARS-CoV-2-mediated pneumonia disease complex. The antibiotic resistance in pneumonia treatment is increasing at an alarming rate. Therefore, carbon-based nanomaterials (CBNs), such as fullerene, carbon dots, graphene, and their derivatives constitute a promising alternative due to their wide-spectrum antimicrobial activity, biocompatibility, biodegradability, and capacity to induce tissue regeneration. Furthermore, the antimicrobial mode of action is mainly physical (e.g., membrane distortion), characterized by a low risk of antimicrobial resistance. In this Review, we evaluated the literature on the antiviral activity and broad-spectrum antimicrobial properties of CBNs. CBNs had antiviral activity against 13 enveloped positive-sense single-stranded RNA viruses, including SARS-CoV-2. CBNs with low or no toxicity to humans are promising therapeutics against the COVID-19 pneumonia complex with other viruses, bacteria, and fungi, including those that are multidrug-resistant

    The structural basis of accelerated host cell entry by SARS-CoV-2 dagger

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    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the pandemic coronavirus disease 2019 (COVID-19) that exhibits an overwhelming contagious capacity over other human coronaviruses (HCoVs). This structural snapshot describes the structural bases underlying the pandemic capacity of SARS-CoV-2 and explains its fast motion over respiratory epithelia that allow its rapid cellular entry. Based on notable viral spike (S) protein features, we propose that the flat sialic acid-binding domain at the N-terminal domain (NTD) of the S1 subunit leads to more effective first contact and interaction with the sialic acid layer over the epithelium, and this, in turn, allows faster viral ‘surfing’ of the epithelium and receptor scanning by SARS-CoV-2. Angiotensin-converting enzyme 2 (ACE-2) protein on the epithelial surface is the primary entry receptor for SARS-CoV-2, and protein–protein interaction assays demonstrate high-affinity binding of the spike protein (S protein) to ACE-2. To date, no high-frequency mutations were detected at the C-terminal domain of the S1 subunit in the S protein, where the receptor-binding domain (RBD) is located. Tight binding to ACE-2 by a conserved viral RBD suggests the ACE2-RBD interaction is likely optimal. Moreover, the viral S subunit contains a cleavage site for furin and other proteases, which accelerates cell entry by SARS-CoV-2. The model proposed here describes a structural basis for the accelerated host cell entry by SARS-CoV-2 relative to other HCoVs and also discusses emerging hypotheses that are likely to contribute to the development of antiviral strategies to combat the pandemic capacity of SARS-CoV-2

    Implications derived from S-protein variants of SARS-CoV-2 from six continents

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    Spike (S) protein is a critical determinant of the infectivity and antigenicity of SARS-CoV-2. Several mutations in the spike protein of SARS-CoV-2 have already been detected, and their effect in immune system evasion and enhanced transmission as a cause of increased morbidity and mortality are being investigated. From pathogenic and epidemiological perspectives, spike proteins are of prime interest to researchers. This study focused on the unique variants of S proteins from six continents: Asia, Africa, Europe, Oceania, South America, and North America. In comparison to the other five continents, Africa had the highest percentage of unique S proteins (29.1%). The phylogenetic relationship implies that unique S proteins from North America are significantly different from those of the other five continents. They are most likely to spread to the other geographic locations through international travel or naturally by emerging mutations. It is suggested that restriction of international travel should be considered, and massive vaccination as an utmost measure to combat the spread of COVID-19 pandemic. It is also further suggested that the efficacy of existing vaccines and future vaccine development must be reviewed with careful scrutiny, and if needed, further re-engineered based on requirements dictated by new emerging S protein variants
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