Search results for: total organic content

Authors: Sifi Ibrahim, Benaddou Fatima Zohra, Yousfi Mohamed

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The Marrubium deserti and Ammodaucus leucotrichus L. an Algerian endemic species, has several applications in traditional medicine for example as a remedy for asthma and diabetes, and was found to have antibacterial properties. In this work, an antioxidant and antimicrobial activities was performed on phenolic extracts of Marrubium deserti, Ammodaucus leucotrichus plants. The yield of methanol maceration of these plants is 12.4% and 20.4% respectively. The content of total polyphenols, flavonoids and anthocyanin in methanolic extracts, are varied between 19.52±1.88 and 59.24±3.45 mg/g gallic acid equivalent, and 2.08±0.29 to 1.46±0.39 mg/g quercetin equivalent, and 0.395 to 1.934µmol/g respectively. The total chlorophylls and carotenoids were be ranged from 0.149±0.20 to 1.537±0.20 g/ml and 1.537±0.20 to 0.149 ± 0.20 g/ml, respectively. According to DPPH and FRAP test, the values of EC50 was shows a higher activity of Marrubium deserti than Ammodaucus leucotrichus with EC50 values (DPPH) were 34.53±0.71 μg/mL and 258.60±15.67 mg/ml respectively. The TEAC values of FRAP test was a highly superior for Marrubium deserti 209.66±0.26 mg Equivalent Trolox/g dry residue than Ammodaucus leucotrichus 45.88±2.93 mg Trolox Equivalent/g dry residue. The antimicrobial activity against nine strains of bacteria (Staphylococcus aureus(+), Staphylococcus aureus (-), Bacillus cereus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Salmonella typhi), was showed that the tested extracts are a significant antibacterial activity with inhibition zones ranging from 10 to 50 mm. the value of CMI were ranging from 0.89 to 14.29 mg/ml.

Keywords: phenolic extract, antioxidant activity, antimicrobial activity, Marrubium deserti, Ammodaucus leucotrichus

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Authors: Marcin Zieliński, Marcin Dębowski, Mirosław Krzemieniewski

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The anaerobic degradation of substrates is limited especially by the rate and effectiveness of the first (hydrolytic) stage of fermentation. This stage may be intensified through pre-treatment of substrate aimed at disintegration of the solid phase and destruction of substrate tissues and cells. The most frequently applied criterion of disintegration outcomes evaluation is the increase in biogas recovery owing to the possibility of its use for energetic purposes and, simultaneously, recovery of input energy consumed for the pre-treatment of substrate before fermentation. Hydrodynamic cavitation is one of the methods for organic substrate disintegration that has a high implementation potential. Cavitation is explained as the phenomenon of the formation of discontinuity cavities filled with vapor or gas in a liquid induced by pressure drop to the critical value. It is induced by a varying field of pressures. A void needs to occur in the flow in which the pressure first drops to the value close to the pressure of saturated vapor and then increases. The process of cavitation conducted under controlled conditions was found to significantly improve the effectiveness of anaerobic conversion of organic substrates having various characteristics. This phenomenon allows effective damage and disintegration of cellular and tissue structures. Disintegration of structures and release of organic compounds to the dissolved phase has a direct effect on the intensification of biogas production in the process of anaerobic fermentation, on reduced dry matter content in the post-fermentation sludge as well as a high degree of its hygienization and its increased susceptibility to dehydration. A device the efficiency of which was confirmed both in laboratory conditions and in systems operating in the technical scale is a hydrodynamic generator of cavitation. Cavitators, agitators and emulsifiers constructed and tested worldwide so far have been characterized by low efficiency and high energy demand. Many of them proved effective under laboratory conditions but failed under industrial ones. The only task successfully realized by these appliances and utilized on a wider scale is the heating of liquids. For this reason, their usability was limited to the function of heating installations. Design of the presented cavitation generator allows achieving satisfactory energy efficiency and enables its use under industrial conditions in depolymerization processes of biomass with various characteristics. Investigations conducted on the laboratory and industrial scale confirmed the effectiveness of applying cavitation in the process of biomass destruction. The use of the cavitation generator in laboratory studies for disintegration of sewage sludge allowed increasing biogas production by ca. 30% and shortening the treatment process by ca. 20 - 25%. The shortening of the technological process and increase of wastewater treatment plant effectiveness may delay investments aimed at increasing system output. The use of a mechanical cavitator and application of repeated cavitation process (4-6 times) enables significant acceleration of the biogassing process. In addition, mechanical cavitation accelerates increases in COD and VFA levels.

Keywords: hydrodynamic cavitation, pretreatment, biomass, methane fermentation, Virginia fanpetals

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Authors: A. Paz, S. Cortés Diéguez, J. M. Cruz, A. B. Moldes, J. M. Domínguez

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Synthetic dyes are extensively used in the paper, food, leather, cosmetics, pharmaceutical and textile industries. Wastewater resulting from their production means several environmental problems. Improper disposal of theirs effluents involves adverse impacts and not only about the colour, also on water quality (Total Organic Carbon, Biological Oxygen Demand, Chemical Oxygen Demand, suspended solids, salinity, etc.) on flora (inhibition of photosynthetic activity), fauna (toxic, carcinogenic, and mutagenic effects) and human health. The aim of this work is to optimize the decolourisation process of different types of dyes by Bacillus aryabhattai. Initially, different types of dyes (Indigo Carmine, Coomassie Brilliant Blue and Remazol Brilliant Blue R) and suitable culture media (Nutritive Broth, Luria Bertani Broth and Trypticasein Soy Broth) were selected. Then, a central composite design (CCD) was employed to optimise and analyse the significance of each abiotic parameter. Three process variables (temperature, salt concentration and agitation) were investigated in the CCD at 3 levels with 2-star points. A total of 23 experiments were carried out according to a full factorial design, consisting of 8 factorial experiments (coded to the usual ± 1 notation), 6 axial experiments (on the axis at a distance of ± α from the centre), and 9 replicates (at the centre of the experimental domain). Experiments results suggest the efficiency of this strain to remove the tested dyes on the 3 media studied, although Trypticasein Soy Broth (TSB) was the most suitable medium. Indigo Carmine and Coomassie Brilliant Blue at maximal tested concentration 150 mg/l were completely decolourised, meanwhile, an acceptable removal was observed using the more complicate dye Remazol Brilliant Blue R at a concentration of 50 mg/l.

Keywords: Bacillus aryabhattai, dyes, decolourisation, central composite design

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Authors: Nuntaporn Aukkanit

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Objective of this study was to investigate hydrocolloids (pectin, carboxyl methylcellulose, and alginate) for their influences on the oil absorption in vacuum fried mango chips. Usage of hydrocolloids significantly (p≤0.05) affected fried mango oil uptake. Control samples (without hydrocolloids) had high fat content at 24.57g/100g whereas other samples, treated with 0.5g pectin/100ml water exhibited the highest decrease of oil absorption. Fat content of chips, treated with 0.5 g pectin /100ml was 14.01g/100g. With this concentration of pectin at 0.5 g /100ml, fat content could be reduced by 43%. Moreover, chips treated with 0.5 g pectin/100ml water had the highest sensory scores (color, appearance, crispiness and overall acceptability). These results showed that pectin was the most effective hydrocolloid for low fat vacuum fried mango chips production.

Keywords: alginate, carboxyl methylcellulose, hydrocolloids, oil absorption, pectin, vacuum fried mango chips

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Authors: García López

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The Government Departments of Health have the task of informing and educating citizens about public health issues. For this, they use channels like Twitter, key in the search for health information and the propagation of content. The tweets, important in the virality of the content, may contain emotions that influence the contagion and exchange of knowledge. The goal of this study is to perform an analysis of the emotional projection of health information shared on Twitter by official American accounts: the disease control account CDCgov, National Institutes of Health, NIH, the government agency HHSGov, and the professional organization PublicHealth. For this, we used Tone Analyzer, an International Business Machines Corporation (IBM) tool specialized in emotion detection in text, corresponding to the categorical model of emotion representation. For 15 days, all tweets from these accounts were analyzed with the emotional analysis tool in text. The results showed that their tweets contain an important emotional load, a determining factor in the success of their communications. This exposes that official accounts also use subjective language and contain emotions. The predominance of emotion joy over sadness and the strong presence of emotions in their tweets stimulate the virality of content, a key in the work of informing that government health departments have.

Keywords: emotions in tweets, emotion detection in the text, health information on Twitter, American health official accounts, emotions on Twitter, emotions and content

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Authors: Canan Türeli̇, İrem Nur Yeşi̇lyurt

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A total of nine stomatopod crustaceans have been reported from the eastern Mediterranean, with the eight from the Turkey coasts and three from the Levantine coast of Turkey (Squilla massavensis (Linnaeus,1758), Erugosquilla massavensis (Kossmann, 1880), Clorida albolitura (Ahyong&Naiyanetr, 2000). E. massavensis is the most successful Red Sea immigrant, and it is now the dominant eastern Levantine stomatopod. At this research, carapace length/total length- weight relationship of 2 erythrean mantis shrimp, E. massavensis and C. albolitura was studied in Yumurtalık Cove, in the Northeastern Mediterranean of Turkey. Samples were collected monthly from July 2014 to June 2015 (except February), using bottom trawl net into three different depth strata; 0- 10 m, 10-20 m, 20-50m. E. massavensis samples were caught all studied time, except winter, in the three depth range but C. albolitura samples were caught only in July, October and May's months. A total of 572 specimens of the E. massavensis and 12 specimens of the C. albolitura were collected and analyzed. Morphometric equations for the conversions of total length and weight, carapace lengths were constructed for males, females, combined sexes for E. massavensis and C. albolitura. The b-values for total length (TL)-weight (W) in males and females for E. massavensis were 2.738 and 2.725 respectively and for carapace length (CL)-total length (TL) they were 1.041 and 0.978, relatively. The b-values (total length-weight) were determined for combined sexes of E. massavensis and C. albolitura as: 2.771, 1.852 relatively. In both species, the relative growth of weight and total length was found highly positively allometric. However, carapace length showed negative allometry in females of E. Massavensis.

Keywords: Clorida albolitura, Erugosquilla massavensis, Erythrean stomatopod, length/length-weight relationships

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Authors: Keri̇m Emre Öksüz, Şaduman Şen, Uğur Şen

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0.5 wt. % B2O3–doped Ba (Ti1-xZrx) O3, (x=0-0.4) lead-free nanoceramics were synthesized using the solid-state reaction method by adopting the ball milling technique. The influence of the substitution content on crystallographic structure, phase transition, microstructure and sintering behaviour of BT and BZT ceramics were investigated. XRD analysis at room temperature revealed a structural transformation from tetragonal to rhombohedral with enhancement of ZrO2 content in the barium titanate matrix. The scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) were used to investigate microstructure and surface morphology of the sintered samples. The evolution of the Raman spectra was studied for various compositions, and the spectroscopic signature of the corresponding phase was determined. Scanning Electron Microscope (SEM) observations revealed enhanced microstructural uniformity and retarded grain growth with increasing Zr content.

Keywords: BaTiO3, barium-titanate-zirconate, nanoceramics, raman spectroscopy

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Authors: A. E. Delgado, W. Aperador

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This study evaluated the incidence of concentrated natural fibre, as well as the effects of adding a crosslinking agent on the torque when those components are mixed with low density polyethylene (LDPE). The natural fibre has a particle size of between 0.8-1.2mm and a moisture content of 0.17%. An internal mixer was used to measure the torque required to mix the polymer with the fibre. The effect of the fibre content and crosslinking agent on the torque was also determined. A change was observed in the morphology of the mixes using SEM differential scanning microscopy.

Keywords: WPC, DCP, LDPE, natural fibre, torque

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Authors: D. Nareshyadav, K. Anand Kishore, D. Bhagawan

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Water scarcity is the much-identified issue all over the world. The available sources of water need to be reused to sustainable future. The present work explores the treatment of dye wastewater using combinative photocatalysis and ceramic nanofiltration membrane. Commercial ceramic membrane and TiO₂ catalyst were used in this study to investigate the removal of crystal violet dye from the aqueous solution. The effect of operating parameters such as inlet pressure, initial concentration of crystal violet dye, catalyst (TiO₂) loading, initial pH was investigated in the individual system as well as the combined system. In this study, 95 % of dye water was decolorized and 89 % of total organic carbon (TOC) was removed by the hybrid system for 500 ppm of dye and 0.75 g/l of TiO₂ concentrations at pH 9. The operation of the integrated photocatalytic reactor and ceramic membrane filtration has shown the maximum removal of crystal violet dye compared to individual systems. Hence this proposed method may be effective for the removal of Crystal violet dye from effluents.

Keywords: advanced oxidation process, ceramic nanoporous membrane, dye degradation/removal, hybrid system, photocatalysis

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Authors: Soumeya Fekkoun, Djelloul Ghezali, Doumandji Salaheddine

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The majority of the mite soil contributes to decompose the organic matter in the soil, the richness or poverty is a way of knowing the quality of the soil, in this regard we studied the ecological side of the soil mite in a forest park «coast of Algeria». 6 by taking soil samples every month for the year 2010/2011 .The samples are collected and extracted using the technique of Berlese Tullgren. It was obtained 604 individuals. These riches can indicate the fertility of soil and knead the high proportion of organic material in it. The largest number observed in the spring, followed by the separation of the 252 individuals fall 222 individuals and then the summer with 106 individuals and winter 80 individuals. Among the 18 families obtained. Scheloribatidae is the most dominant with 30.6% followed by Ceratozetidae with 16%, then Euphthiracaridae 14%. The families remain involved with low percentages. the diversity index Schanonweaver varied between 2.3 bits in the summer and 3.83 bits in the spring. As the results of the analysis statistic confirm the existence of a clear difference between the four seasons and the richness of soil mite and diversity.

Keywords: soil mite, forest, coast of Algeria, diversity

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Authors: S. Shamohammadi, L. Razavi

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This paper based on the principle concepts of SCS-CN model, a new mathematical model for computation of retention potential (S) presented. In the mathematical model, not only precipitation-runoff concepts in SCS-CN model are precisely represented in a mathematical form, but also new concepts, called “maximum retention” and “total retention” is introduced, and concepts of potential retention capacity, maximum retention, and total retention have been separated from each other. In the proposed model, actual retention (F), maximum actual retention (Fmax), total retention (S), maximum retention (Smax), and potential retention (Sp), for the first time clearly defined, so that Sp is not variable, but a function of morphological characteristics of the watershed. Indeed, based on the mathematical relation of the conceptual curve of SCS-CN model, the proposed model provides a new method for the computation of actual retention in watershed and it simply determined runoff based on. In the corresponding relations, in addition to Precipitation (P), Initial retention (Ia), cumulative values of actual retention capacity (F), total retention (S), runoff (Q), antecedent moisture (M), potential retention (Sp), total retention (S), we introduced Fmax and Fmin referring to maximum and minimum actual retention, respectively. As well as, ksh is a coefficient which depends on morphological characteristics of the watershed. Advantages of the modified version versus the original model include a better precision, higher performance, easier calibration and speed computing.

Keywords: model, mathematical, retention, watershed, SCS

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Authors: Wararut Buncharoen, Kanokporn Saenphet, Supap Saenphet

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Benign prostatic hyperplasia (BPH) is a reproductive problem, affecting elderly men worldwide. Several factors particularly free radical reaction and oxidative damage have been contributed to be key factors leading to the development of BPH. A number of medicinal plants with high antioxidant properties are extensively constituted in Thai herbal pharmacopoeia for treating BPH. These plants may prevent or delay the progression of BPH through an antioxidant mechanism. Thus, this study was to prove the antioxidant and anti-lipid peroxidation potential of medicinal plants traditionally used for the treatment of BPH such as Artabotrys harmandii Finet & Gagnep. Miq., Uvaria rufa Blume, Anomianthus dulcis (Dunal) J. Sinclair and Caesalpinia sappan Linn. Antioxidant parameters including free radical (2, 2-azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS•+), 2, 2-diphenyl-1-picrylhydrazyl (DPPH•) and superoxide) scavenging, ferric reducing power and anti-lipid peroxidation activity were determined in different crude extracts from the stem of these four plants. Total phenolic and ascorbic contents were also investigated. The highest total phenolic content was shown in ethyl acetate crude extract of A. dulcis (510 ± 26.927 µg GAE/g extract) while the highest ascorbic content was found in ethanolic extract of U. rufa (234.727 ± 30.356 µg AAE/g extract). The strongest scavenging activity of ABTS•+ and DPPH• was found in ethyl acetate extract of C. sappan with the IC50 values of 0.469 and 0.255 mg/ml, respectively. The petroleum ether extracts of C. sappan and U. rufa at concentration of 1 mg/ml exhibited high scavenging activity toward superoxide radicals with the inhibition of 37.264 ± 8.672 and 34.434 ± 6.377 %, respectively. Ethyl acetate crude extract of C. sappan displayed the greatest reducing power. The IC50 value of water extract of A. dulcis was 1.326 mg/ml which indicated the strongest activity in the inhibition of lipid-peroxidation among all plant extracts whereas the IC50 value of the standard, butyl hydroxyl toluene was 1.472 µg/ml. Regarding all the obtained results, it can be concluded that the stem of A. dulcis, U. rufa and C. sappan are the potential natural antioxidants and could have an importance as therapeutic agents in the preventing free radicals and oxidative damage related diseases including BPH.

Keywords: anti-lipid peroxidation, antioxidant, benign prostatic hyperplasia, Thai medicinal plants

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Authors: Rohan Bhasin

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Agrammatism in non-fluent Aphasia Cases can be defined as a language disorder wherein a patient can only use content words ( nouns, verbs and adjectives ) for communication and their speech is devoid of functional word types like conjunctions and articles, generating speech of with extremely rudimentary grammar . Past approaches involve Speech Therapy of some order with conversation analysis used to analyse pre-therapy speech patterns and qualitative changes in conversational behaviour after therapy. We describe this approach as a novel method to generate functional words (prepositions, articles, ) around content words ( nouns, verbs and adjectives ) using a combination of Natural Language Processing and Deep Learning algorithms. The applications of this approach can be used to assist communication. The approach the paper investigates is : LSTMs or Seq2Seq: A sequence2sequence approach (seq2seq) or LSTM would take in a sequence of inputs and output sequence. This approach needs a significant amount of training data, with each training data containing pairs such as (content words, complete sentence). We generate such data by starting with complete sentences from a text source, removing functional words to get just the content words. However, this approach would require a lot of training data to get a coherent input. The assumptions of this approach is that the content words received in the inputs of both text models are to be preserved, i.e, won't alter after the functional grammar is slotted in. This is a potential limit to cases of severe Agrammatism where such order might not be inherently correct. The applications of this approach can be used to assist communication mild Agrammatism in non-fluent Aphasia Cases. Thus by generating these function words around the content words, we can provide meaningful sentence options to the patient for articulate conversations. Thus our project translates the use case of generating sentences from content-specific words into an assistive technology for non-Fluent Aphasia Patients.

Keywords: aphasia, expressive aphasia, assistive algorithms, neurology, machine learning, natural language processing, language disorder, behaviour disorder, sequence to sequence, LSTM

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Authors: Luisa Maria Arrechea Fajardo, Luz Stella Cadavid Rodriguez

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Fish is one of the most commercialized foods worldwide. However, this industry only takes advantage of about 55% of the product's weight, the rest is converted into waste, which is mainly composed of viscera, gills, scales and spines. Consequently, if these wastes are not used or disposed of properly, they cause serious environmental impacts. This is the case of Tumaco (Colombia), the second largest producer of marine fisheries on the Colombian Pacific coast, where artisanal fishermen process more than 50% of the commercialized volume. There, fishing waste is disposed primarily in the ocean, causing negative impacts on the environment and society. Therefore, in the present research, a proposal was made to take advantage of fishing waste through anaerobic treatments, through which it is possible to obtain products with high added value from organic waste. The research was carried out in four stages. First, the production of volatile fatty acids (VFA) in semi-continuous 4L reactors was studied, evaluating three hydraulic retention times (HRT) (10, 7 and 5 days) with four organic loading rates (OLR) (16, 14, 12 and 10 gVS/L/day), the experiment was carried out for 150 days. Subsequently, biogas production was evaluated from the solid digestate generated in the VFA production reactors, initially evaluating the biochemical methane potential (BMP) of 4 total solid concentrations (1, 2, 4 and 6% TS), for 40 days and then, with the optimum TS concentration (2 gVS/L/day), 2 HRT (15 and 20 days) in semi-continuous reactors, were evaluated for 100 days. Finally, the integration of the processes was carried out with the best conditions found, a first phase of VFA production from fishing waste and a second phase of biogas production from unrecovered VFAs and unprocessed material Additionally, an VFA membrane extraction system was included. In the first phase, a liquid digestate with a concentration and VFA production yield of 59.04 gVFA/L and 0.527 gVFA/gVS, respectively, was obtained, with the best condition found (HRT:7 days and OLR: 16 gVS/L/día), where acetic acid and isobutyric acid were the predominant acids. In the second phase of biogas production, a BMP of 0.349 Nm3CH4/KgVS was reached, and it was found as best HRT 20 days. In the integration, the isovaleric, butyric and isobutyric acid were the VFA with the highest percentage of extraction, additionally a 106.67% increase in biogas production was achieved. This research shows that anaerobic treatments are a promising technology for an environmentally safe management of fishing waste and presents the basis of a possible biorefinery.

Keywords: biogas production, fishing waste, VFA membrane extraction, VFA production

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Authors: F. Stephen Joe, V. Sathya Narayanan, V. R. Sanal Kumar

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A comprehensive review of the literature on photovoltaic cells has been carried out for exploring the better options for cost efficient technologies for future solar cell applications. Literature review reveals that the Bulk Heterojunction (BHJ) Polymer Solar cells offer special opportunities as renewable energy resources. It is evident from the previous studies that the device fabricated with TiOx layer shows better power conversion efficiency than that of the device without TiOx layer. In this paper, authors designed a controlled BHJ solar cell using a modified organic vapor spray deposition technique facilitated with a vertical-moving gun named as 'Stephen Joe Technique' for getting a desirable surface pattern over the substrate to improving its efficiency over the years for industrial applications. We comprehended that the efficient processing and the interface engineering of these solar cells could increase the efficiency up to 5-10 %.

Keywords: BHJ polymer solar cell, photovoltaic cell, solar cell, Stephen Joe technique

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Authors: M. Hosseinnejad, K. Gharanjig, S. Moradian

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A novel metal free organic dyes based on indigo was prepared and used as sensitizers in dye-sensitized solar cells. The synthesized dye together with its corresponding intermediates were purified and characterized by analytical techniques. Such techniques confirmed the corresponding structures of dye and its intermediate and the yield of all the stages of dye preparation were calculated to be above 85%. Fluorometric analyses show fluorescence in the green region of the visible spectrum for dye. Oxidation potential measurements for dye ensured an energetically permissible and thermodynamically favourable charge transfer throughout the continuous cycle of photo-electric conversion. Finally, dye sensitized solar cells were fabricated in order to determine the photovoltaic behaviour and conversion efficiencies of dye. Such evaluations demonstrate rather medium conversion efficiencies of 2.33% for such simple structured synthesized dye. Such conversion efficiencies demonstrate the potentiality of future use of such dye structures in dye-sensitized solar cells with respect to low material costs, ease of molecular tailoring, high yields of reactions, high performance and ease of recyclability.

Keywords: conversion efficiency, Dye-sensitized solar cells, indigo, photonic material

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Authors: Samira Rostom, Robert Symonds, Robin W. Hughes

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Hydrogen is considered as one of the most important clean and renewable energy carriers for a sustainable energy future. However, its efficient and cost-effective purification remains challenging. This paper presents the potential of using metal–organic frameworks (MOFs) in combination with pressure swing adsorption (PSA) technology for syngas based H2 purification. PSA process analysis is done considering high pressure and elevated temperature process conditions, it reduces the demand for off-gas recycle to the fuel reactor and simultaneously permits higher desorption pressure, thereby reducing the parasitic load on the hydrogen compressor. The elevated pressure and temperature adsorption we present here is beneficial to minimizing overall process heating and cooling demand compared to existing processes. Here, we report the comparative performance of zeolite-5A, Cu-BTC, and the mix of zeolite-5A/Cu-BTC for H2 purification from syngas typical of those exiting water-gas-shift reactors. The MOFs were synthesized hydrothermally and then mixed systematically at different weight ratios to find the optimum composition based on the adsorption performance. The formation of different compounds were characterized by XRD, N2 adsorption and desorption, SEM, FT-IR, TG, and water vapor adsorption technologies. Single-component adsorption isotherms of CO2, CO, CH4, N2, and H2 over single materials and composites were measured at elevated pressures and different temperatures to determine their equilibrium adsorption capacity. The examination of the stability and regeneration performance of metal–organic frameworks was carried out using a gravimetric system at temperature ranges of 25-150℃ for a pressure range of 0-30 bar. The studies of adsorption/desorption on the MOFs showed selective adsorption of CO2, CH4, CO, and N2 over H2. Overall, the findings of this study suggest that the Ni-MOF-74/Cu-BTC composites are promising candidates for industrial H2 purification processes.

Keywords: MOF, H2 purification, high T, PSA

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Authors: Ferhat Mohamed, Boukhatem Mohamed Nadjib, Chemat Farid

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Simultaneous distillation–extraction (SDE) is routinely used by analysts for sample preparation prior to gas chromatography analysis. In this work, a new process design and operation for microwave assisted simultaneous distillation – solvent extraction (MW-SDE) of volatile compounds was developed. Using the proposed method, isolation, extraction and concentration of volatile compounds can be carried out in a single step. To demonstrate its feasibility, MW-SDE was compared with the conventional technique, Simultaneous distillation–extraction (SDE), for gas chromatography-mass spectrometry (GC-MS) analysis of volatile compounds in a fresh orange juice and a dry spice “carvi seeds”. SDE method required long time (3 h) to isolate the volatile compounds, and large amount of organic solvent (200 mL of hexane) for further extraction, while MW-SDE needed little time (only 30 min) to prepare sample, and less amount of organic solvent (10 mL of hexane). These results show that MW-SDE–GC-MS is a simple, rapid and solvent-less method for determination of volatile compounds from aromatic plants.

Keywords: essential oil, extraction, distillation, carvi seeds

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Authors: Melissa Angus Baboun

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Utilizing a Critical Discourse Analysis (CDA) methodology and a theoretical framework based on disability studies, how Jamaican and Trinidadian newspapers discussed issues relating to the Deaf community were examined. The term deaf was inputted into the search engine tool of the online website for the Jamaica Observer and the Trinidad & Tobago Guardian. All 27 articles that contained the term deaf in its content and were written between August 1, 2017 and November 15, 2017 were chosen for the study. The data analysis was divided into three steps: (1) listing and analysis instances of metaphorical deafness (e.g. fall on deaf ears), (2) categorization of the content of the articles into the models of disability discourse (the medical, socio-cultural, and superscrip models of disability narratives), and (3) the analysis of any additional data found. A total of 42% of the articles pulled for this study did not deal with the Deaf community in any capacity, but rather instances of the use of idiomatic expressions that use deafness as a metaphor for a non-physical, undesirable trait. The most common idiomatic expression found was fall on deaf ears. Regarding the models of disability discourse, eight articles were found to follow the socio-cultural model, two were found to follow the medical model, and two were found to follow the superscrip model. The additional data found in these articles include two instances of the term deaf and mute, an overwhelming use of lower case d for the term deaf, and the misuse of the term translator (to mean interpreter).

Keywords: deafness, disability, news coverage, Caribbean newspapers

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Authors: I. A. Yola

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Impact of poultry dropping, cow dung and rumen content on utilization and proximate composition of Oreochromis niliticus, Clarias gariepinus and Cyprinus capio in a polyculture system were studied. The research was conducted over a period of 52 weeks. Poultry droppings (PD), cow dung (CD) and rumen content (RC) were applied at three levels 30g,60g and 120g/m2/week, 25g,50g and 100g/m2/week and 22g, 44g and 88g/m2/week treatment, respectively. The control only conventional feed with 40% CP without manure application was used. Physicochemical and biological properties measured were higher in manure pond than control. The difference was statistically significant (P < 0.05) between and within treatments with exception of temperature with a combined mean of 27.900C. The water was consistently alkaline with mean values for pH of 6.61, transparency 22.6cm, conductivity 35.00µhos/cm, dissolved oxygen 4.6 mg/l, biological oxygen demand 2.8mg/l, nitrate and phosphates 0.9mg/l and 0.35mg/l, respectively. The three fish species increase in weight with increased manure rate, with a higher value in PD treatment on C. capio record 340g, O. niloticus weighed 310g and C. gariepinus 280g over the experimental period. Fishes fed supplementary diet (control) grew bigger with highest value on C. capio (685g) O. niloticus (620g) and then C. gariepinus (526g). The differences were statistically significant (P < 0.05). The result of whole body proximate analysis indicated that various manures and rates had an irregular pattern on the protein and ash gain per 100g of fish body weight gain. The combined means for whole fish carcass protein, lipids, moisture, ash and gross energy were 11.84, 2.43, 74.63, 3.00 and 109.9 respectively. The notable exceptions were significant (p < 0.05) increases in body fat and gross energy gains in all fish species accompanied by decreases in percentages of moisture as manure rates increased. Survival percentage decreases from 80% to 70%. It is recommended to use poultry dropping as manure/feeds at the rate of 120kg/ha/week for good performances in polyculture.

Keywords: organic manure, Nile tilapia, African mud fish, common carp, proximate composition

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Authors: A. Bayat, R. Bello-Mendoza, D. G. Wareham

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Two major categories of green waste are fruit and vegetable (FV) waste and garden and yard (GY) waste. Although, anaerobic digestions (AD) is able to manage FV waste; there is less confidence in the conditions for AD to handle GY wastes (grass, leaves, trees and bush trimmings); mainly because GY contains lignin and other recalcitrant organics. GY in the dry state (TS ≥ 15 %) can be digested at mesophilic temperatures; however, little methane data has been reported under thermophilic conditions, where conceivably better methane yields could be achieved. In addition, it is suspected that at lower solids concentrations, the methane yield could be increased. As such, the aim of this research is to find the temperature and solids concentration conditions that produce the most methane; under two different temperature regimes (mesophilic, thermophilic) and three solids states (i.e. 'dry', 'semi-dry' and 'wet'). Twenty liters of GY waste was collected from a public park located in the northern district in Tehran. The clippings consisted of freshly cut grass as well as dry branches and leaves. The GY waste was chopped before being fed into a mechanical blender that reduced it to a paste-like consistency. An initial TS concentration of approximately 38 % was achieved. Four hundred mL of anaerobic inoculum (average total solids (TS) concentration of 2.03 ± 0.131 % of which 73.4% were volatile solid (VS), soluble chemical oxygen demand (sCOD) of 4.59 ± 0.3 g/L) was mixed with the GY waste substrate paste (along with distilled water) to achieve a TS content of approximately 20 %. For comparative purposes, approximately 20 liters of FV waste was ground in the same manner as the GY waste. Since FV waste has a much higher natural water content than GY, it was dewatered to obtain a starting TS concentration in the dry solid-state range (TS ≥ 15 %). Three samples were dewatered to an average starting TS concentration of 32.71 %. The inoculum was added (along with distilled water) to dilute the initial FV TS concentrations down to semi-dry conditions (10-15 %) and wet conditions (below 10 %). Twelve 1-L batch bioreactors were loaded simultaneously with either GY or FV waste at TS solid concentrations ranging from 3.85 ± 1.22 % to 20.11 ± 1.23 %. The reactors were sealed and were operated for 30 days while being immersed in water baths to maintain a constant temperature of 37 ± 0.5 °C (mesophilic) or 55 ± 0.5 °C (thermophilic). A maximum methane yield of 115.42 (L methane/ kg VS added) was obtained for the GY thermophilic-wet AD combination. Methane yield was enhanced by 240 % compared to the GY waste mesophilic-dry condition. The results confirm that high temperature regimes and small solids concentrations are conditions that enhance methane yield from GY waste. A similar trend was observed for the anaerobic digestion of FV waste. Furthermore, a maximum value of VS (53 %) and sCOD (84 %) reduction was achieved during the AD of GY waste under the thermophilic-wet condition.

Keywords: anaerobic digestion, thermophilic, mesophilic, total solids concentration

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Authors: Kanika Kalra, Harmeet Kaur, Dinesh Goyal

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Total phenolics were extracted from waste orange peels by solvent extraction and alkali hydrolysis method. The most efficient solvents for extracting phenolic compounds from waste biomass were methanol (60%) > dimethyl sulfoxide > ethanol (60%) > distilled water. The extraction yields were significantly impacted by solvents (ethanol, methanol, and dimethyl sulfoxide) due to varying polarity and concentrations. Extraction of phenolics using 60% methanol yielded the highest phenolics (in terms of gallic acid equivalent (GAE) per gram of biomass) in orange peels. Alkali hydrolyzed extract from orange peels contained 7.58±0.33 mg GAE g⁻¹. By using the solvent extraction technique, it was observed that 60% methanol is comparatively the best-suited solvent for extracting polyphenolic compounds and gave the maximum yield of 4.68 ± 0.47 mg GAE g⁻¹ in orange peel extracts. DPPH radical scavenging activity and reducing the power of orange peel extract were checked, where 60% methanolic extract showed the highest antioxidant activity, 85.50±0.009% for DPPH, and dimethyl sulfoxide (DMSO) extract gave the highest yield of 1.75±0.01% for reducing power ability of the orange peels extract. Characterization of the polyphenolic compounds was done by using Fourier transformation infrared (FTIR) spectroscopy. Solvent and alkali hydrolysed extracts were evaluated for antibacterial activity using the agar well diffusion method against Gram-positive Bacillus subtilis MTCC441 and Gram-negative Escherichia coli MTCC729. Methanolic extract at 300µl concentration showed an inhibition zone of around 16.33±0.47 mm against Bacillus subtilis, whereas, for Escherichia coli, it was comparatively less. Broth-based turbidimetric assay revealed the antibacterial effect of different volumes of orange peel extracts against both organisms.

Keywords: orange peels, total phenolic content, antioxidant, antibacterial

Procedia PDF Downloads 67

Authors: Prasanna Belur, P. R. Ashwini, Sampath Charanyaa, I. Regupathi

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Indian oil sardine (Sardinella longiceps) are one of the richest and cheapest sources of n-3 polyunsaturated fatty acids (n-3 PUFA) such as Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA). The health benefits conferred by n-3 PUFA upon consumption, in the prevention and treatment of coronary, neuromuscular, immunological disorders and allergic conditions are well documented. Natural refined Indian Sardine oil generally contain about 25% (w/w) n-3 PUFA along with various unsaturated and saturated fatty acids in the form of mono, di, and triglycerides. Having high concentration of n-3 PUFA content in the glyceride form is most desirable for human consumption to avail maximum health benefits. Thus, enhancing the n-3 PUFA content while retaining it in the glyceride form with green technology is the need of the hour. In this study, refined Indian Sardine oil was subjected to selective hydrolysis by Candida antartica lipase to enhance n-3 PUFA content. The degree of hydrolysis and enhancement of n-3 PUFA content was estimated by determining acid value, Iodine value, EPA and DHA content (by Gas Chromatographic methods after derivitization) before and after hydrolysis. Various reaction parameters such as pH, temperature, enzyme load, lipid to aqueous phase volume ratio and incubation time were optimized by conducting trials with one parameter at a time approach. Incubating enzyme solution with refined sardine oil with a volume ratio of 1:1, at pH 7.0, for 60 minutes at 50 °C, with an enzyme load of 60 mg/ml was found to be optimum. After enzymatic treatment, the oil was subjected to refining to remove free fatty acids and moisture content using previously optimized refining technology. Enzymatic treatment at the optimal conditions resulted in 12.11 % enhancement in Degree of hydrolysis. Iodine number had increased by 9.7 % and n-3 PUFA content was enhanced by 112 % (w/w). Selective enhancement of n-3 PUFA glycerides, eliminating saturated and unsaturated fatty acids from the oil using enzyme is an interesting preposition as this technique is environment-friendly, cost effective and provide natural source of n-3 PUFA rich oil.

Keywords: Candida antartica, lipase, n-3 polyunsaturated fatty acids, sardine oil

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Authors: Cláudia Moço, Maria Santos, Carlos Arsénio, Débora Mendes, Miguel Oliveira. José Paulo Da Silva

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Construction industry generates large amounts of waste all over the world. About 450 million tons of construction and demolition wastes (C&DW) are produced annually in the European Union. C&DW are highly heterogeneous materials in size and composition, which imposes strong difficulties on their management. Directive n.º 2008/98/CE, of the European Parliament and of the Council of 6 November establishes that 70 % of the C&DW have to be recycled by 2020. To evaluate possible applications of these materials, a detailed physical, chemical and environmental characterization is necessary. Multi Triagem, Lda. is a company located in Algarve (Portugal) and was supported by the European Regional Development Fund (grant QREN 30307 Multivalor) to quantify and characterize the received C&DW, in order to evaluate their possible applications. This evaluation, performed in collaboration with the University of Algarve, involves a physical, chemical and environmental detailed characterization of the received C&DW. In this work we report on the amounts, trial procedures and properties of the C&DW received over a period of fifteen month. In this period the company received C&DW coming from 393 different origins. The total amount was 32.458 tons, mostly mixtures containing concrete, masonry/mortar and soil/rock. Most of C&DW came from demodulation constructions and diggings. The organic/inert component, namely metal, glass, wood and plastics, were screened first and account for about 3 % of the received materials. The remaining materials were screened and grouped according to their origin and contents, the latter evaluated by visual inspection. Twenty five samples were prepared and submitted to a detailed physical, chemical and environmental analysis. The C&DW aggregates show lower quality properties than natural aggregates for concrete preparation and unbound layers of road pavements. However, chemical analyzes indicated that most samples are environmentally safe. A continuous monitoring of the presence of heavy metals and organic compounds is needed in order to perform a proper screening of the C&DW. C&DW aggregates provide a good alternative to natural aggregates.

Keywords: construction and demolition wastes, waste classification, waste composition, waste screening

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Authors: Prima Luna, Afroditi Chatzifragkou, Dimitris Charalampopoulos

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Sorghum byproducts, namely bran, stalk, and panicle are examples of lignocellulosic biomass. These raw materials contain large amounts of polysaccharides, in particular hemicelluloses, celluloses, and lignins, which if efficiently extracted, can be utilised for the development of a range of added value products with potential applications in agriculture and food packaging sectors. The aim of this study was to characterise fractions extracted from sorghum bran and stalk with regards to their physicochemical properties that could determine their applicability as food-packaging materials. A sequential alkaline extraction was applied for the isolation of cellulosic, hemicellulosic and lignin fractions from sorghum stalk and bran. Lignin content, phenolic content and antioxidant capacity were also investigated in the case of the lignin fraction. Thermal analysis using differential scanning calorimetry (DSC) and X-Ray Diffraction (XRD) revealed that the glass transition temperature (T_g) of cellulose fraction of the stalk was ~78.33 ^oC at amorphous state (~65%) and water content of ~5%. In terms of hemicellulose, the T_g value of stalk was slightly lower compared to bran at amorphous state (~54%) and had less water content (~2%). It is evident that hemicelluloses generally showed a lower thermal stability compared to cellulose, probably due to their lack of crystallinity. Additionally, bran had higher arabinose-to-xylose ratio (0.82) than the stalk, a fact that indicated its low crystallinity. Furthermore, lignin fraction had T_g value of ~93 ^oC at amorphous state (~11%). Stalk-derived lignin fraction contained more phenolic compounds (mainly consisting of p-coumaric and ferulic acid) and had higher lignin content and antioxidant capacity compared to bran-derived lignin fraction.

Keywords: alkaline extraction, bran, cellulose, hemicellulose, lignin, stalk

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Authors: Olaide Ruth Aderibigbe, Oluwatoyin Oluwole

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Pigeon pea is one of the minor leguminous plants; though underutilised, it is used traditionally by farmers to alleviate hunger and malnutrition. Pigeon pea is cultivated in Nigeria by subsistence farmers. It is rich in protein and minerals, however, its utilisation as food is only common among the poor and rural populace who cannot afford expensive sources of protein. One of the factors contributing to its limited use is the high antinutrient content which makes it indigestible, especially when eaten by children. The development of value-added products that can reduce the antinutrient content and make the nutrients more bioavailable will increase the utilisation of the crop and contribute to reduction of malnutrition. This research, therefore, determined the effects of different roasting temperatures (130 0C, 140 0C, and 150 0C) on the proximate, mineral and antinutrient component of a pigeon pea snack. The brown variety of pigeon pea seeds were purchased from a local market- Otto in Lagos, Nigeria. The seeds were cleaned, washed, and soaked in 50 ml of water containing sugar and salt (4:1) for 15 minutes, and thereafter the seeds were roasted at 130 0C, 140 0C, and 150 0C in an electric oven for 10 minutes. Proximate, minerals, phytate, tannin and alkaloid content analyses were carried out in triplicates following standard procedures. The results of the three replicates were polled and expressed as mean±standard deviation; a one-way analysis of variance (ANOVA) and the Least Significance Difference (LSD) were carried out. The roasting temperatures significantly (P<0.05) affected the protein, ash, fibre and carbohydrate content of the snack. Ready-to-eat snack prepared by roasting at 150 0C significantly had the highest protein (23.42±0.47%) compared the ones roasted at 130 0C and 140 0C (18.38±1.25% and 20.63±0.45%, respectively). The same trend was observed for the ash content (3.91±0.11 for 150 0C, 2.36±0.15 for 140 0C and 2.26±0.25 for 130 0C), while the fibre and carbohydrate contents were highest at roasting temperature of 130 0C. Iron, zinc, and calcium were not significantly (P<0.5) affected by the different roasting temperatures. Antinutrients decreased with increasing temperature. Phytate levels recorded were 0.02±0.00, 0.06±0.00, and 0.07±0.00 mg/g; tannin levels were 0.50±0.00, 0.57±0.00, and 0.68±0.00 mg/g, while alkaloids levels were 0.51±0.01, 0.78±0.01, and 0.82±0.01 mg/g for 150 0C, 140 0C, and 130 0C, respectively. These results show that roasting at high temperature (150 0C) can be utilised as a processing technique for increasing protein and decreasing antinutrient content of pigeon pea.

Keywords: antinutrients, pigeon pea, protein, roasting, underutilised species

Procedia PDF Downloads 134

Authors: Kalyani Mer

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Hydrogen peroxide (H₂O₂) is one of the most efficient and commonly used oxidants in in-situ chemical oxidation (ISCO) of organic contaminants. In the present study, we investigated the activation of H₂O₂ by heavy metal (nickel and lead metal ions) loaded biochar for phenol degradation in an aqueous solution (concentration = 100 mg/L). It was found that H₂O₂ can be effectively activated by biochar, which produces hydroxyl (•OH) radicals owing to an increase in the formation of persistent free radicals (PFRs) on biochar surface. Ultrasound treated (30s duration) biochar, chemically activated by 30% phosphoric acid and functionalized by diethanolamine (DEA) was used for the adsorption of heavy metal ions from aqueous solutions. It was found that modified biochar could remove almost 60% of nickel in eight hours; however, for lead, the removal efficiency reached up to 95% for the same time duration. The heavy metal loaded biochar was further used for the degradation of phenol in the absence and presence of H₂O₂ (20 mM), within 4 hours of reaction time. The removal efficiency values for phenol in the presence of H₂O₂ were 80.3% and 61.9%, respectively, by modified biochar loaded with nickel and lead metal ions. These results suggested that the biochar loaded with nickel exhibits a better removal capacity towards phenol than the lead loaded biochar when used in H₂O₂ based oxidation systems. Meanwhile, control experiments were set in the absence of any activating biochar, and the removal efficiency was found to be 19.1% when only H₂O₂ was added in the reaction solution. Overall, the proposed approach serves a dual purpose of using biochar for heavy metal ion removal and treatment of organic contaminants by further using the metal loaded biochar for H₂O₂ activation in ISCO processes.

Keywords: biochar, ultrasound, heavy metals, in-situ chemical oxidation, chemical activation

Procedia PDF Downloads 131

Authors: Maria Magdy Danial Riad

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The objective of this study was to investigate the effect of different protein sources with different degradability ratios during late gestation of ewes on colostrum composition and its IgG concentration, body weight change of dams, and birth weight of their lambs. Objectives: 35 multiparous native crossbred ewes (BW= 59±2.5kg) were randomly allocated to five dietary treatments (7 ewes / treatment) for 2 months prior to lambing. Methods: Experimental diets were isonitrogenous (12.27% CP) and isocaloric (2.22 Mcal ME/kg DM). In diet I (the control), solvent extract soybeans (SESM 33% RUP of CP), II feed grade urea (FGU 31% RUP), III slow release urea (SRU 31% RUP). As sources of undegradable protein, extruded expeller SBM-EESM 40 (37% RUP) and extruded expeller SBM-EESM 60 (41% RUP) were used in groups IV and V, respectively. Results showed no significant effect on feed intake, crude protein (CP), metabolizable energy (ME), and body condition score (BCS). Ewes fed the 37% RUP diet gained more (p<0.05) weight compared with ewes fed the 31% RUP diet (5.62 vs. 2.5kg). Ewes in EESM 60 had the highest levels of fat, protein, total solid, solid not fat, and immunoglobulin and the lowest in urea N content (P< 0.05) in colostrum during the first 24hrs after lambing. Conclusions: Protein source and RUP levels in ewes’ diets had no significant effect (P< 0.05) on lambs’ birth weight and ewes' blood biochemical parameters. Increasing the RUP content of diet during late gestation resulted in an increase in colostrum constituents and its IgG level but had no effect on ewes’ performance and their lambs’ outcome.

Keywords: colostrum, ewes, lambs output, pregnancy, undegradable protein

Procedia PDF Downloads 47

Authors: Gu Pang, Bartosz Gebka

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We forecast the demand of total container throughput at the Indonesia’s largest seaport, Tanjung Priok Port. We propose four univariate forecasting models, including SARIMA, the additive Seasonal Holt-Winters, the multiplicative Seasonal Holt-Winters and the Vector Error Correction Model. Our aim is to provide insights into whether forecasting the total container throughput obtained by historical aggregated port throughput time series is superior to the forecasts of the total throughput obtained by summing up the best individual terminal forecasts. We test the monthly port/individual terminal container throughput time series between 2003 and 2013. The performance of forecasting models is evaluated based on Mean Absolute Error and Root Mean Squared Error. Our results show that the multiplicative Seasonal Holt-Winters model produces the most accurate forecasts of total container throughput, whereas SARIMA generates the worst in-sample model fit. The Vector Error Correction Model provides the best model fits and forecasts for individual terminals. Our results report that the total container throughput forecasts based on modelling the total throughput time series are consistently better than those obtained by combining those forecasts generated by terminal-specific models. The forecasts of total throughput until the end of 2018 provide an essential insight into the strategic decision-making on the expansion of port's capacity and construction of new container terminals at Tanjung Priok Port.

Keywords: SARIMA, Seasonal Holt-Winters, Vector Error Correction Model, container throughput

Procedia PDF Downloads 499

Authors: Yu-Jen Shih, Juan-Zhang Lou

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Nitrogenous compounds, such as NH4+/NH3 and NO3-, have become important contaminants in water resources. Excessive concentration of NH3 leads to eutrophication, which poses a threat to aquatic organisms in the environment. Electrochemical oxidation emerged as a promising water treatment technology, offering advantages such as simplicity, small-scale operation, and minimal reliance on additional chemicals. In this study, a nickel-based metal-organic framework (Ni-MOF) was synthesized using 2-amino terephthalic acid (BDC-NH2) and nickel nitrate. The Ni-MOF was further carbonized as derived nickel oxide and nitrogen-carbon composite, Ni/NiOx/NC. The nickel oxide within the 2D porous carbon texture served as active sites for ammonia oxidation. Results of characterization showed that the Ni-MOF was a hexagonal and flaky nanoparticle. With increasing carbonization temperature, the nickel ions in the organic framework re-crystallized as NiO clusters on the surfaces of the 2D carbon. The electrochemical surface area of Ni/NiOx/NC significantly increased as to improve the efficiency of ammonia oxidation. The phase transition of Ni(OH)2⇌NiOOH at around +0.8 V was the primary mediator of electron transfer. Batch electrolysis was conducted under constant current and constant potential modes. The electrolysis parameters included pyrolysis temperatures, pH, current density, initial feed concentration, and electrode potential. The constant current batch experiments indicated that via carbonization at 800 °C, Ni/NiOx/NC(800) was able to decrease the ammonium nitrogen of 50 mg-N/L to below 1 ppm within 4 hours at a current density of 3 mA/cm2 and pH 11 with negligible oxygenated nitrogen formation. The constant potential experiments confirmed that N2 nitrogen selectivity was enhanced up to 90% at +0.8 V.

Keywords: electrochemical oxidation, nickel oxyhydroxide, metal-organic framework, ammonium, nitrate

Procedia PDF Downloads 57