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21.
Martin JW Barri T Han X Fedorak PM El-Din MG Perez L Scott AC Jiang JT 《Environmental science & technology》2010,44(21):8350-8356
Ozonation can degrade toxic naphthenic acids (NAs) in oil sands process-affected water (OSPW), but even after extensive treatment a residual NA fraction remains. Here we hypothesized that mild ozonation would selectively oxidize the most biopersistent NA fraction, thereby accelerating subsequent NA biodegradation and toxicity removal by indigenous microbes. OSPW was ozonated to achieve approximately 50% and 75% NA degradation, and the major ozonation byproducts included oxidized NAs (i.e., hydroxy- or keto-NAs). However, oxidized NAs are already present in untreated OSPW and were shown to be formed during the microbial biodegradation of NAs. Ozonation alone did not affect OSPW toxicity, based on Microtox; however, there was a significant acceleration of toxicity removal in ozonated OSPW following inoculation with native microbes. Furthermore, all residual NAs biodegraded significantly faster in ozonated OSPW. The opposite trend was found for ozonated commercial NAs, which are known to contain no significant biopersistent fraction. Thus, we suggest that ozonation preferentially degraded the most biopersistent OSPW NA fraction, and that ozonation is complementary to the biodegradation capacity of microbial populations in OSPW. The toxicity of ozonated OSPW to higher organisms needs to be assessed, but there is promise that this technique could be applied to accelerate the bioremediation of large volumes of OSPW in Northern Alberta, Canada. 相似文献
22.
A.M. Al-Sabagh M.R. Noor El-Din R.E. Morsi M.Z. Elsabee 《Journal of Petroleum Science and Engineering》2009,65(3-4):139-146
Four comb-like copolymers derived from styrene-maleic anhydride copolymer were prepared and characterized by FTIR, 1H-NMR and elemental analysis. The molecular weight was determined using GPC and their intrinsic viscosity was measured. The prepared polymers were investigated as pour point depressants and flow improvers for waxy crude oil and it was found that, the maximum depression was obtained by the sample that has long branch chain (PPD4) from 27 °C to − 3 °C (ΔPP = 30 °C, at 10,000 ppm), while the minimum depression was exhibited by short branch chain, PPD1 (ΔPP = 21 °C) at the same conditions.The effect of these polymers on the rheology and flow properties of Qarun waxy crude oil was investigated. It was found that the Bingham yield value (τβ) decreased from 6.0 Pa s to 0.5 Pa s for PPD4 at 27 °C and 10,000 ppm. The dynamic viscosity also decreased from 110 mPa s to 24 mPa s for the same sample and the same conditions. 相似文献
23.
Stephen G. Giteru Derek H. Ramsey Yakun Hou Lei Cong Anand Mohan Alaa El-Din Ahmed Bekhit 《Comprehensive Reviews in Food Science and Food Safety》2023,22(1):643-687
The growing global population and lifestyle changes have increased the demand for specialized diets that require protein and other essential nutrients for humans. Recent technological advances have enabled the use of food bioresources treated as waste as additional sources of alternative proteins. Sheep wool is an inexpensive and readily available bioresource containing 95%–98% protein, making it an outstanding potential source of protein for food and biotechnological applications. The strong structure of wool and its indigestibility are the main hurdles to achieving its potential as an edible protein. Although various methods have been investigated for the hydrolysis of wool into keratin, only a few of these, such as sulfitolysis, oxidation, and enzymatic processes, have the potential to generate edible keratin. In vitro and in vivo cytotoxicity studies reported no cytotoxicity effects of extracted keratin, suggesting its potential for use as a high-value protein ingredient that supports normal body functions. Keratin has a high cysteine content that can support healthy epithelia, glutathione synthesis, antioxidant functions, and skeletal muscle functions. With the recent spike in new keratin extraction methods, extensive long-term investigations that examine prolonged exposure of keratin generated from these techniques in animal and human subjects are required to ascertain its safety. Food applications of wool could improve the ecological footprint of sheep farming and unlock the potential of a sustainable protein source that meets demands for ethical production of animal protein. 相似文献
24.
Mostafa A. Teama Mohamed A. Kassab Burns A. Cheadle Maher A. Mesbah Ibtehal F. Mohamed Ezz S. El-Din 《Egyptian Journal of Petroleum》2018,27(4)
Ten wells (EW-4, EW-5, EW-6, EW-7, EW-8, EW-9, EW-10, EW-12, EW-13 and EW-15) were interpreted using the composite well logs, data of core analysis, gamma-ray logs, formation micro-imager logs (FMI), and 3D seismic data in SEGY format to understand the stratigraphy of the onshore, Nile Delta, Egypt.The amplitude analysis of 3-D seismic horizon slice of Lower Abu Madi rock unit together with the lithostratigraphic correlation through the study area depending on the gamma-ray log “HSGR” (left to right increasing), and the identification of type of bed geometry, nature of bed contacts, type of the sedimentary structures and the dominant formative paleocurrents by using some available borehole micro-resistivity images (FMI) and core photos. All of these techniques are used together to define the different depositional facies and depositional environment of the Messinian clastics (Lower Abu Madi rock unit), which is considered to be the main reservoir in the El-Wastani gas field, onshore Nile Delta, Egypt.The present study of depositional pattern of the Upper Miocene clastics reservoir (Lower Abu Madi rock unit) revealed that it is represented by high sinuous meandering channels or paleo-valley and three types of fluvial facies were defined; channel fill, channel margin, and floodplain basin. 相似文献
25.
Arafa Doaa Ahmed Moustafa Hossam El-Din Ali-Eldin Amr M. T. Ali Hesham A. 《Multimedia Tools and Applications》2022,81(17):23735-23776
Multimedia Tools and Applications - Alzheimer’s disease (AD) is a form of brain disorder that causes functions’ loss in a person’s daily activity. Due to the tremendous progress... 相似文献
26.
A cotton linter pulp, a bagasse dissolving pulp and a bagasse paper pulp were subjected to cold sodium hydroxide refining and the resulting changes in their chemical, physical and submicroscopic characteristics were investigated. In the case of cotton linters the main change took place in the physical and submicroscopic properties and the refining resulted in better reactivity towards xanthation. The α-cellulose content of the paper and viscose pulps increased with alkali concentration until it reached a constant value which depends on the type of pulp and the concentration of alkali. The refining of the paper and viscose pulps impaired their reactivity towards xanthation. The presence of the more hydrophilic hemicellulose increased the swelling ability of the fibres and made them more reactive towards xanthation. The undesirable effects of drying after refining with high alkali concentration could be overcome if the DP is sufficiently lowered. In this case the resulting shorter chain macromolecules dissolve more readily during xanthation. 相似文献
27.
Effective detoxification of oil sands process-affected water (OSPW) is one issue associated with bitumen extraction in the Alberta oil sands. It has been suggested that reclamation ponds can be used to passively treat OSPW, potentially allowing for its safe return to the environment. In this study, OSPW was sampled in two batches (A and B) from the Syncrude Canada Ltd. West In-Pit (WIP) settling pond and from three experimental reclamation ponds - Big Pit, FE5, and TPW. Acute (10 d) and chronic (until adult emergence) exposures of Chironomus dilutus larvae to OSPW were conducted and survival, growth, development, and behavior were assessed. Masses of larvae exposed to WIP-OSPW were 64-77% less than the freshwater control (p < 0.001). Similarly, chronic exposure to WIP-OSPW resulted in significantly (p < 0.05) less pupation than in the freshwater control, with 31% (A) and 71% (B) less pupation of larvae exposed to WIP-OSPW. Rates of emergence were significantly less for larvae exposed to WIP-OSPW, with only 13% (A) and 8% (B) of larvae emerging as adults when exposed to WIP-OSPW, compared to 81% in the freshwater control (p < 0.0001). Pupation and emergence rates were significantly less in TPW than freshwater control (p < 0.05), but there were no differences observed in Big Pit or FE5. Lesser toxicity was observed in reclaimed OSPW compared to fresh OSPW and this coincided with lesser concentrations of NAs. The results presented are consistent with the hypothesis that an organic fraction is the cause of the toxicity of OSPW toward C. dilutus and that OSPW aged in reclamation ponds retains toxicity and therefore, more aggressive, targeted treatment of OSPW is required to accelerate decreases. 相似文献
28.
29.
Pourrezaei P Drzewicz P Wang Y Gamal El-Din M Perez-Estrada LA Martin JW Anderson J Wiseman S Liber K Giesy JP 《Environmental science & technology》2011,45(19):8452-8459
Coagulation/flocculation (CF) by use of alum and cationic polymer polyDADMAC, was performed as a pretreatment for remediation of oil sands process-affected water (OSPW). Various factors were investigated and the process was optimized to improve efficiency of removal of organic carbon and turbidity. Destabilization of the particles occurred through charge neutralization by adsorption of hydroxide precipitates. Scanning electron microscope images revealed that the resultant flocs were compact. The CF process significantly reduced concentrations of naphthenic acids (NAs) and oxidized NAs by 37 and 86%, respectively, demonstrating the applicability of CF pretreatment to remove a persistent and toxic organic fraction from OSPW. Concentrations of vanadium and barium were decreased by 67-78% and 42-63%, respectively. Analysis of surface functional groups on flocs also confirmed the removal of the NAs compounds. Flocculation with cationic polymer compared to alum, caused toxicity toward the benthic invertebrate, Chironoums dilutus, thus application of the polymer should be limited. 相似文献
30.
Sue-Siang Teh Alaa El-Din Bekhit Alan Carne John Birch 《Sensing and Instrumentation for Food Quality and Safety》2014,8(2):92-104
The effect of the defatting process, acid and alkali extractions on the physicochemical and functional properties of hemp, flax and canola protein isolates was studied. The defatting process enriched the protein content from around 35 to 52–55 % in the defatted oilseed cakes. Further treatment with acid and alkali led to the highest enrichment (P < 0.05) in the protein content (>90 %). The defatting process produced the lightest (P < 0.05) colour compared to the parent oilseed cakes and the protein isolates. Alkali extraction produced protein isolates with the highest (P < 0.05) water holding capacity while the original oilseed cakes had the highest oil holding capacity. Acid and alkali extractions produced protein isolates with the highest emulsifying activity and emulsion stability. The alkaline soluble flax protein isolate and acid hemp protein isolate had the highest (P < 0.05) creaming stability and largest droplet size respectively. Amino acid profiles of protein isolates after acid and alkali extraction were improved, leading to a protein suitable for fortification in food products that meet human nutrition requirements. 相似文献