Search results for: activated carbon adsorption

Authors: Chia-Yu Chang, Yi-Feng Lin

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CO2 capture has attracted significant research attention due to global warming. Among the various CO2 capture methods, membrane technology has proven to be highly efficient in capturing CO2 due to the ease at which this technology can be scaled up, its low energy consumptions, small area requirements and overall environmental friendliness for use by industrial plants. Capturing CO2 is to use a membrane contactor with a combination of water-repellent porous membranes and chemical absorption processes. In a CO2 membrane contactor system, CO2 passes through a hydrophobic porous membrane in the gas phase to contact the amine absorbent in the liquid phase. Consequently, additional CO2 gas is absorbed by amine absorbents. This study examines highly porous Polydimethylsiloxane (PDMS)/Polystyrene (PS) Nanofibrous Membranes and successfully coated onto a macroporous Al2O3 membrane. The performance of these materials in a membrane contactor system for CO2 absorption is also investigated. Compared with pristine PS nanofibrous membranes, the PDMS/PS nanofibrous membranes exhibit greater solvent resistance and mechanical strength, making them more suitable for use in CO2 capture by the membrane contactor. The resulting hydrophobic membrane contactor also demonstrates the potential for large-scale CO2 absorption during post-combustion processes in power plants.

Keywords: CO2 capture, polystyrene, polydimethylsiloxane, superhydrophobic

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Authors: Md. Shoffikul Islam, Hongqing Hu

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Reducing trace elements' mobility and bioavailability through amendment addition, especially biochar (BC), is a cost-effective and efficient method to address their toxicity in the soil environment. However, the low molecular weight organic acids (LMWOAs) in the rhizosphere could affect BC's efficiency to stabilize trace metals as the LMWOAs could either mobilize or fix metals in the soils. Therefore, understanding the BC's and LMWOAs' interaction mechanisms on metals stabilization in the rhizosphere is crucial. The present study explored the impact of BC derived from rice husk and citric acid (CA) and the combination of BC and CA on the redistribution of cadmium (Cd), lead (Pb), and zinc (Zn) among their geochemical forms through incubation experiment. The changes of zeta potential and X-ray diffraction (XRD) pattern of BC and BC-amended soils to investigate the probable mechanisms of trace elements' immobilization by BC under the CA attack were also examined. The rice husk BC at 5% (w/w) was mixed with the air-dry soil (an Anthrosols) contaminated with Cd, Pb, and Zn in the plastic pot. The 2, 5, 10, and 20 mM kg-1 (w/v) of CA were added separately into the pot. All the ingredients were mixed thoroughly with the soil. A control (CK) treatment was also prepared without BC and CA addition. After 7, 15, and 60 days of incubation with 60% (w/v) moisture level at 25 °C, the incubated soils were determined for pH and EC and were sequentially extracted to assess the metals' transformation in soil. The electronegative charges and XRD peaks of BC and BC-amended soils were also measured. Compared to CK, the application of BC, low level of CA (2 mM kg-1 soil) (CA2), and BC plus the low concentration of CA (BC-CA2) considerably declined the acid-soluble Cd, Pb, and Zn in which BC-CA2 was found to be the most effective treatment. The reversed trends were observed concerning the high levels of CA (>5-20 mM kg-1 soil) and the BC plus high concentrations of CA treatments. BC-CA2 changed the highest amounts of acid-soluble and reducible metals to the oxidizable and residual forms with time. The most increased electronegative charges of BC-CA2 indicate its (BC-CA2) highest Cd, Pb, and Zn immobilizing efficiency, probably through metals adsorption and fixation with the negative charge sites. The XRD study revealed the presence of P, O, CO32-, and Cl1- in BC, which might be responsible for the precipitation of CdCO3, pyromorphite, and hopeite in the case of Cd, Pb, and Zn immobilization, respectively. The findings depicted that the low concentration of CA increased metals' stabilization, whereas the high levels of CA enhanced their mobilization. The BC-CA2 emerged as the best amendment among treatments for metals stabilization in contaminated soils.

Keywords: Biochar, citric acid, immobilization, trace elements contaminated soil

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Authors: Jae Hee Chung, Tae Uk Kang, Byung Seo Kim

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This study aims to propose design technologies for the energy-saving modular housing units considering environmental and aesthetic aspects. Modular houses are environmentally friendly based on 3R (Reduce, Reuse, Recycle) because they can dramatically reduce carbon dioxide and construction wastes generated during the construction, use, and disposal process by the pre-fabrication at the factory and the recyclability of the unit, compared to the existing construction methods. The existing modular housing, however, tends to focus on quantitative aspects of energy reduction, such as windows, insulation, and introduction of renewable energy, and there is not much research on energy-saving type units considering the environmental aspects such as daylighting and ventilation, and the design that goes beyond the standardized appearance. Therefore, this study conducts theoretical investigation and analytical case studies on the energy-saving methods through various architectural planning elements as well as materials like insulation considering the environmental and aesthetic aspects in the modular housing. Then, comparative analysis on the energy efficiency through the energy simulation is conducted. As a conclusion, the energy-saving modular housing units considering environmental and aesthetics aspects are proposed. It is expected that this study will contribute to the supply and activation of modular housing through deriving design technologies for the energy-saving modular housing units that consider not only quantitative aspects but also qualitative aspects.

Keywords: aesthetic aspects, energy-saving, environmental, modular housing

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Authors: G. Krishnamoorthy, S. Anandhakumar

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The effect of D-Lysine (D-Lys) on collagen with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide(EDC)/N-hydroxysuccinimide(NHS) initiated cross linking using experimental and modelling tools are evaluated. The results of the Coll-D-Lys-EDC/NHS scaffold also indicate an increase in the tensile strength (TS), percentage of elongation (% E), denaturation temperature (Td), and decrease the decomposition rate compared to L-Lys-EDC/NHS. Scanning electron microscopic (SEM) and atomic force microscopic (AFM) analyses revealed a well ordered with properly oriented and well-aligned structure of scaffold. The D-Lys stabilizes the scaffold against degradation by collagenase than L-Lys. The cell assay showed more than 98% fibroblast viability (NIH3T3) and improved cell adhesions, protein adsorption after 72h of culture when compared with native scaffold. Cell attachment after 74h was robust, with cytoskeletal analysis showing that the attached cells were aligned along the fibers assuming a spindle-shape appearance, despite, gene expression analyses revealed no apparent alterations in mRNA levels, although cell proliferation was not adversely affected. D-Lysine (D-Lys) plays a pivotal role in the self-assembly and conformation of collagen fibrils. The D-Lys assisted EDC/NHS initiated cross-linking induces the formation of an carboxamide by the activation of the side chain -COOH group, followed by aminolysis of the O-iso acylurea intermediates by the -NH2 groups are directly joined via an isopeptides bond. This leads to the formation of intra- and inter-helical cross links. Modeling studies indicated that D-Lys bind with collagen-like peptide (CLP) through multiple H-bonding and hydrophobic interactions. Orientational changes in collagenase on CLP-D-Lys are observed which may decrease its accessibility to degradation and stabilize CLP against the action of the former. D-Lys has lowest binding energy and improved fibrillar-assembly and staggered alignment without the undesired structural stiffness and aggregations. The proteolytic machinery is not well equipped to deal with Coll-D-Lys than Coll-L-Lys scaffold. The information derived from the present study could help in designing collagenolytically stable heterochiral collagen based scaffold for biomedical applications.

Keywords: collagen, collagenase, collagen like peptide, D-lysine, heterochiral collagen scaffold

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Authors: Krittiya Pornmai, Sumaeth Chavadej

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The increasing in global energy demand has affected the climate change caused by the generation of greenhouse gases. Therefore, the objective of this work was to investigate a direct production of synthesis gas from a CO₂-containing natural gas by using gliding arc discharge plasma technology. In this research, the effects of steam reforming, combined steam reforming and partial oxidation, and using multistage gliding arc discharge system on the process performance have been discussed. The simulated natural gas used in this study contains 70% methane, 5% ethane, 5% propane, and 20% carbon dioxide. In comparison with different plasma reforming processes (under their optimum conditions), the steam reforming provides the highest H₂ selectivity resulting from the cracking reaction of steam. In addition, the combined steam reforming and partial oxidation process gives a very high CO production implying that the addition of both oxygen and steam can offer the acceptably highest synthesis gas production. The stage number of plasma reactor plays an important role in the improvement of CO₂ conversion. Moreover, 3 stage number of plasma reactor is considered as an optimum stage number for the reforming of CO₂-containing natural gas with steam and partial oxidation in term of providing low energy consumption as compared with other plasma reforming processes.

Keywords: natural gas, reforming process, gliding arc discharge, plasma technology

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Authors: Hossein Lotfizadeh, André McDonald, Amit Kumar

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Renewable energy resources, which can supplement space and water heating for residential buildings, can have a noticeable impact on natural gas consumption and air pollution. This study considers a technical analysis of a combined solar water heating system with evacuated tube solar collectors for different solar coverage, ranging from 20% to 100% of the total roof area of a typical residential building located in Edmonton, Alberta, Canada. The alternative heating systems were conventional (non-condensing) and condensing tankless water heaters and condensing boilers that were coupled to solar water heating systems. The performance of the alternative heating systems was compared to a traditional heating system, consisting of a conventional boiler, applied to houses of various gross floor areas. A comparison among the annual natural gas consumption, carbon dioxide (CO₂) mitigation, and emissions for the various house sizes indicated that the combined solar heating system can reduce the natural gas consumption and CO₂ emissions, and increase CO₂ mitigation for all the systems that were studied. The results suggest that solar water heating systems are potentially beneficial for residential heating system applications in terms of energy savings and CO₂ mitigation.

Keywords: CO2 emissions, CO2 mitigation, natural gas consumption, solar water heating system

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Authors: Tharaki S. Hettiarachchi

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Sustainable construction has gained massive attention in the present world as the construction industry is highly responsible for carbon emissions and other types of unsustainable practices. Yet, the construction industry has not been able to completely attain sustainable goals. Therefore, the present study aims to identify the extent to which sustainability has been considered within the scope of construction project management and to analyze the challenges, gaps, and constraints associated. Accordingly, this study develops a sustainable framework to integrate in construction project management. In accomplishing the research aim, this research integrates a qualitative approach while relying on secondary data sources. The data shall be then analyzed with the use of a systematic literature review (SLR) method while following the PRISMA (2020) guideline and represented in a statistical form. The outcomes of this study may become highly significant in identifying the nature of the existing sustainable frameworks associated with construction project management scopes and to develop a new framework to integrate in order to enhance the effectiveness of sustainable applications in construction management. The outcomes of this research may benefit present and future construction professionals and academicians to organize sustainable construction-related knowledge in a useful way to apply in practical implementation for effective project management. Overall, this study directs present and future construction professionals toward an advanced construction project management mechanism.

Keywords: construction, framework development, project management, sustainability

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Authors: Jaqueline Nichi, Leila Da Costa Ferreira, Fabiana Barbi Seleguim, Gabriela Marques Di Giulio, Mariana Barbieri

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The transport sector is responsible for approximately 55% of global greenhouse gas (GHG) emissions, in addition to pollution and other negative externalities, such as road accidents and congestion, that impact the routine of those who live in large cities. The objective of this article is to discuss the application and use of distinct mobility technologies such as climate adaptation and mitigation measures in the context of smart cities in the Global South. The documentary analysis is associated with 22 semi structured interviews with managers who work with mobility technologies in the public and private sectors and in civil society organizations to explore solutions in multilevel governance for smart and low-carbon mobility based on the case study from the city of São Paulo, Brazil. The hypothesis that innovation and technology to mitigate and adapt to climate impacts are not yet sufficient to make mobility more sustainable has been confirmed. The results indicate four relevant aspects for advancing a climate agenda in smart cities: integrated planning, coproduction of knowledge, experiments in governance, and new means of financing to guarantee the sustainable sociotechnical transition of the sector.

Keywords: urban mobility, climate change, smart cities, multilevel governance

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Authors: S. K. M. Nzaba, H. H. Nyoni, B. Ntsendwana, B. B. Mamba, A. T. Kuvarega

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Azo dye effluents, released into water bodies are not only toxic to the ecosystem but also pose a serious impact on human health due to the carcinogenic and mutagenic effects of the compounds present in the dye discharge. Conventional water treatment methods such as adsorption, flocculation/coagulation and biological processes are not effective in completely removing most of the dyes and their natural degradation by-products. Advanced oxidation processes (AOPs) have proven to be effective technologies for complete mineralization of these recalcitrant pollutants. Therefore, there is a need for new technology that can solve the problem. Thus, this study examined the photocatalytic degradation of an azo dye brilliant black (BB) using non-metal/metal codoped TiO₂. N, Pt co-doped TiO₂ photocatalysts were prepared by a modified sol-gel method using amine-terminated polyamidoamine dendrimer generation 0 (PAMAM G0), amine-terminated polyamidoamine dendrimer generation 1 ( PAMAM G1) and hyperbranched polyethyleneimine (HPEI) as templates and source of nitrogen. Structural, morphological, and textural properties were evaluated using scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM/EDX), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), Fourier- transform infrared (FTIR), Raman spectroscopy (RS), photoluminescence (PL) and ultra-violet /visible spectroscopy (UV-Vis). The synthesized photocatalysts exhibited lower band gap energies as compared to the Degussa P-25 revealing a red shift in band gap towards the visible light absorption region. Photocatalytic activity of N, Pt co-doped TiO₂ was measured by the reaction of photocatalytic degradation of brilliant black (BB) dye. The N, metal codoped TiO₂ containing 0.5 wt. % of the metal consisted mainly of the anatase phase as confirmed by XRD results of all three samples, with a particle size range of 13–30 nm. The particles were largely spherical and shifted the absorption edge well into the visible region. Band gap reduction was more pronounced for the N, Pt HPEI (Pt 0.5 wt. %) codoped TiO₂ compared to PAMAM G0 and PAMAM G1. Consequently, codoping led to an enhancement in the photocatalytic activity of the materials for the degradation of brilliant black (BB).

Keywords: codoped TiO₂, dendrimer, photodegradation, wastewater

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Authors: J. M. Muñoz, Y. Vasquez, P. Oyola, M. Rubio

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All emissions of contaminants inside of homes, offices, school and another enclosure closer that affect the health of those who inhabit or use them are cataloged how indoor pollution. The importance of this study is because individuals spend most of their time in indoors ambient. The main indoor pollutants are oxides of nitrogen (NOₓ), sulfur dioxide (SO₂), carbon monoxide (CO) and particulate matter (PM). Combustion heaters are an important source of pollution indoors. It will be measured: NOₓ, SO₂, CO, PM₂,₅ y PM₁₀ continuous and discreet form at indoor and outdoor of two households with different heating energy; kerosene and electricity (control home) respectively, in addition to environmental parameters such as temperature. With the values obtained in the 'control home' it will be possible estimate the contaminants transport from outside to inside of the household and later the contribution generated by kerosene heating. Transporting the emissions from burning kerosene to a photochemical chamber coupled to a continuous and discreet measuring system of contaminants it will be evaluated the oxidation of the emissions and formation of secondary particulate matter. It will be expected watch a contaminants transport from outside to inside of the household and the kerosene emissions present a high potential of formation secondary particulate matter.

Keywords: heating, indoor pollution, kerosene, secondary particulate matter

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Authors: Ying Chen

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Conservation Agriculture in a sustainable way of farming, as it brings many benefits, such as preventing soil from erosion and degradation, improving soil health, conserving energy, and sequestrating carbon. However, adoption of conservation agriculture has been progressing slowly in some part of the world due to some challenges. Among them, seeding in heavy crop residue is challenging, especially in corn production systems. Weed control is also challenging in conservation agriculture. This research aimed to investigate some technologies that can address these challenges. For crop residue management, vertical tillage and vertical seeding have been studied in multiple research projects. Results showed that vertical tillage and seeding were able to deal with crop residue through cutting residue into small segments, which would not plug seeder in the sub-sequent seeding. Vertical tillage is a conservation tillage system, as it leaves more than 30% crop residue on soil surface while incorporating some residue into the shallow soil layer for fast residue decomposition. For weed control, mechanical weeding can reduce chemical inputs in crop production. A tine weeder was studied for weed control during the early growing season of several field crops (corn, soybean, flax, and pea). Detail results of these studies will be shared at the conference.

Keywords: tillage, seeding, mechanical weeding, crop residue

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Authors: Sujeeta Karki, Jeeban Poudel, Ja Hyung Choi, Sea Cheon Oh

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A lab-scale fluidized bed was used for the study of sewage sludge, a non-lignocellulosic biomass, torrefaction. The influence of torrefaction temperature ranging from 200–350 °C and residence time of 0–50 minutes on the physical and chemical properties of the torrefied product was investigated. Properties of the torrefied product were analyzed on the basis of degree of torrefaction, ultimate and proximate analysis, gas analysis and chemical exergy. The degree of torrefaction and chemical exergy had a positive influence on increasing the torrefaction temperature. Moreover, the effect of torrefaction temperature and residence time on the elemental variation of sewage sludge exhibited an increase in the weight percentage of carbon while the content of H/C and O/C molar ratios decreased. The product gas emitted during torrefaction was analyzed to study the pathway of hydrocarbons and oxygen-containing compounds. The compounds with oxygen were emitted at higher temperatures in contrast to hydrocarbon gases. An attempt was made to obtain the chemical exergy of sewage sludge. In addition, the study of various correlations for predicting the calorific value of torrefied sewage sludge was made.

Keywords: chemical exergy, degree of torrefaction, fluidized bed, higher heating value (HHV), O/C and H/C molar ratios, sewage sludge

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Authors: Afshin Farahbakhsh, Hoda Khodadadi

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In this paper, we compare five methods of biological fuel cell fabrication by combining a Shewanella oneidensis microbial anode and a laccase-modified air-breathing cathode. As a result of biofuel cell laccase with graphite nanofibers, carbon surface (PAMAN) on the pt/hpg electrode, graphite sheets MWCNT and with (PG) and (MWCNT) showed, respectively. Describes methods for creating controllable and reproducible bio-anodes and demonstrates the versatility of hybrid biological fuel cells. The laccase-based biocathodes prepared either with the crude extract or with the purified enzyme can provide electrochemically active and stable biomaterials. The laccase-based biocathodes prepared either with the crude extract or with the purified enzyme can provide electrochemically active and stable biomaterials. When the device was fed with transdermal extracts, containing only 30μM of glucose, the average peak power was proportionally lower (0.004mW). The result of biofuel cell with graphite nanofibers showed the enzymatic fuel cell reaches 0.5 V at open circuit voltage with both, ethanol and methanol and the maximum current density observed for E2electrode was 228.94mAcm.

Keywords: enzymatic electrode, fuel cell, immobilization, laccase

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Authors: Tomoko Fukuyama, Osamu Senbu

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Prestressed concrete is used a lot in infrastructures such as roads or bridges. However, poor grout filling and PC steel corrosion are currently major issues of prestressed concrete structures. One of the problems with nondestructive corrosion detection of PC steel is a plastic pipe which covers PC steel. The insulative property of pipe makes a nondestructive diagnosis difficult; therefore a practical technology to detect these defects is necessary for the maintenance of infrastructures. The goal of the research is a development of an electrochemical technique which enables to detect internal defects from the surface of prestressed concrete nondestructively. Ideally, the measurements should be conducted from the surface of structural members to diagnose non-destructively. In the present experiment, a prestressed concrete member is simplified as a layered specimen to simulate a current path between an input and an output electrode on a member surface. The specimens which are layered by mortar and the prestressed concrete constitution materials (steel, polyethylene, stainless steel, or galvanized steel plates) were provided to the alternating current impedance measurement. The magnitude of an applied electric field was 0.01-volt or 1-volt, and the frequency range was from 106 Hz to 10-2 Hz. The frequency spectrums of impedance, which relate to charge reactions activated by an electric field, were measured to clarify the effects of the material configurations or the properties. In the civil engineering field, the Nyquist diagram is popular to analyze impedance and it is a good way to grasp electric relaxation using a shape of the plot. However, it is slightly not suitable to figure out an influence of a measurement frequency which is reciprocal of reaction time. Hence, Bode diagram is also applied to describe charge reactions in the present paper. From the experiment results, the alternating current impedance method looks to be applicable to the insulative material measurement and eventually prestressed concrete diagnosis. At the same time, the frequency spectrums of impedance show the difference of the material configuration. This is because the charge mobility reflects the variety of substances and also the measuring frequency of the electric field determines migration length of charges which are under the influence of the electric field. However, it could not distinguish the differences of the material thickness and is inferred the difficulties of prestressed concrete diagnosis to identify the amount of an air void or a layer of corrosion product by the technique.

Keywords: capacitance, conductance, prestressed concrete, susceptance

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Authors: Nalinee B. Suryawanshi, Vinay M. Bhandari, Laxmi Gayatri Sorokhaibam, Vivek V. Ranade

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Deep desulphurization of transportation fuels is a major environmental concern all over the world and recently prescribed norms for the sulphur content require below 10 ppm sulphur concentrations in fuels such as diesel and gasoline. The existing technologies largely based on catalytic processes such as hydrodesulphurization, oxidation require newer catalysts and demand high cost of deep desulphurization whereas adsorption based processes have limitations due to lower capacity of sulphur removal. The present work is an attempt to provide alternatives for the existing methodologies using a newer non-catalytic process based on hydrodynamic cavitation. The developed process requires appropriate combining of organic and aqueous phases under ambient conditions and passing through a cavitating device such as orifice, venturi or vortex diode. The implosion of vapour cavities formed in the cavitating device generates (in-situ) oxidizing species which react with the sulphur moiety resulting in the removal of sulphur from the organic phase. In this work, orifice was used as a cavitating device and deep desulphurization was demonstrated for removal of thiophene as a model sulphur compound from synthetic fuel of n-octane, toluene and n-octanol. The effect of concentration of sulphur (up to 300 ppm), nature of organic phase and effect of pressure drop (0.5 to 10 bar) was discussed. A very high removal of sulphur content of more than 90% was demonstrated. The process is easy to operate, essentially works at ambient conditions and the ratio of aqueous to organic phase can be easily adjusted to maximise sulphur removal. Experimental studies were also carried out using commercial diesel as a solvent and the results substantiate similar high sulphur removal. A comparison of the two cavitating devices- one with a linear flow and one using vortex flow for effecting pressure drop and cavitation indicates similar trends in terms of sulphur removal behaviour. The developed process is expected to provide an attractive environmental engineering alternative for deep desulphurization of transportation fuels.

Keywords: cavitation, petroleum, separation, sulphur removal

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Authors: Han-Qin Zheng, Yi-Fan Chiang-Hsieh, Chia-Hung Chien, Wen-Chi Chang

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As the most important non-vascular plants, algae have many research applications, including high species diversity, biofuel sources, adsorption of heavy metals and, following processing, health supplements. With the increasing availability of next-generation sequencing (NGS) data for algae genomes and transcriptomes, an integrated resource for retrieving gene expression data and metabolic pathway is essential for functional analysis and systems biology in algae. However, gene expression profiles and biological pathways are displayed separately in current resources, and making it impossible to search current databases directly to identify the cellular response mechanisms. Therefore, this work develops a novel AlgaePath database to retrieve gene expression profiles efficiently under various conditions in numerous metabolic pathways. AlgaePath, a web-based database, integrates gene information, biological pathways, and next-generation sequencing (NGS) datasets in Chlamydomonasreinhardtii and Neodesmus sp. UTEX 2219-4. Users can identify gene expression profiles and pathway information by using five query pages (i.e. Gene Search, Pathway Search, Differentially Expressed Genes (DEGs) Search, Gene Group Analysis, and Co-Expression Analysis). The gene expression data of 45 and 4 samples can be obtained directly on pathway maps in C. reinhardtii and Neodesmus sp. UTEX 2219-4, respectively. Genes that are differentially expressed between two conditions can be identified in Folds Search. Furthermore, the Gene Group Analysis of AlgaePath includes pathway enrichment analysis, and can easily compare the gene expression profiles of functionally related genes in a map. Finally, Co-Expression Analysis provides co-expressed transcripts of a target gene. The analysis results provide a valuable reference for designing further experiments and elucidating critical mechanisms from high-throughput data. More than an effective interface to clarify the transcript response mechanisms in different metabolic pathways under various conditions, AlgaePath is also a data mining system to identify critical mechanisms based on high-throughput sequencing.

Keywords: next-generation sequencing (NGS), algae, transcriptome, metabolic pathway, co-expression

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Authors: Surasak Siripornadulsil, Nutt Poomai, Wilailak Siripornadulsil

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Due to a high ethanol demand, the approach for effective ethanol production is important and has been developed rapidly worldwide. Several agricultural wastes are highly abundant in celluloses and the effective cellulose enzymes do exist widely among microorganisms. Accordingly, the cellulose degradation using microbial cellulose to produce a low-cost substrate for ethanol production has attracted more attention. In this study, the cellulose producing bacterial strain has been isolated from rich straw and identified by 16S rDNA sequence analysis as Acinetobacter sp. KKU44. This strain is able to grow and exhibit the cellulose activity. The optimal temperature for its growth and cellulose production is 37 °C. The optimal temperature of bacterial cellulose activity is 60 °C. The cellulose enzyme from Acinetobacter sp. KKU44 is heat-tolerant enzyme. The bacterial culture of 36 h. showed highest cellulose activity at 120 U/mL when grown in LB medium containing 2% (w/v). The capability of Acinetobacter sp. KKU44 to grow in cellulosic agricultural wastes as a sole carbon source and exhibiting the high cellulose activity at high temperature suggested that this strain could be potentially developed further as a cellulose degrading strain for a production of low-cost substrate used in ethanol production.

Keywords: cellulose enzyme, bagasse, rice straw, rice husk, acinetobacter sp. KKU44

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Authors: Hristina Šalipur, Jasmina Dostanić, Davor Lončarević, Matej Huš

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Photocatalytic water splitting/alcohol photoreforming has been used for the conversion of sunlight energy in the process of hydrogen production due to its sustainability, environmental safety, effectiveness and simplicity. Titanate nanotubes are frequently studied materials since they combine the properties of photo-active semiconductors with the properties of layered titanates, such as the ion-exchange ability. Platinum (Pt) doping into titanate structure has been considered an effective strategy in better separation efficiency of electron-hole pairs and lowering the overpotential for hydrogen production, which results in higher photocatalytic activity. In our work, Pt doped titanate catalysts were synthesized via simple alkaline hydrothermal treatment, incipient wetness impregnation method and temperature-programmed reduction. The structural, morphological and optical properties of the prepared catalysts were investigated using various characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 physisorption, and diffuse reflectance spectroscopy (DRS). The activities of the prepared Pt-doped titanate photocatalysts were tested for hydrogen production via photocatalytic water splitting/alcohol photoreforming process under simulated solar light irradiation. Characterization of synthesized Pt doped titanate catalysts showed crystalline anatase phase, preserved nanotubular structure and high specific surface area. The result showed enhancement of activity in photocatalytic water splitting/alcohol photoreforming in the following order 2-butanol>1-butanol>tert-butanol, with obtained maximal hydrogen production rate of 7.5, 5.3 and 2 mmol g-1 h-1, respectively. Different possible factors influencing the hole scavenging ability, such as hole scavenger redox potential and diffusivity, adsorption and desorption rate of the hole scavenger on the surface and stability of the alcohol radical species generated via hole scavenging, were investigated. The theoretical evaluation using density functional theory (DFT) further elucidated the reaction kinetics and detailed mechanism of photocatalytic water splitting/alcohol photoreforming.

Keywords: hydrogen production, platinum, semiconductor, water splitting, density functional theory

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Authors: M. Bouhoun Ali, A. Y. Badjah Hadj Ahmed, M. Attou, A. Elias, M. A. Didi

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The extraction of uranium(VI) from aqueous solutions has been investigated using 1-hydroxyhexadecylidene-1,1-diphosphonic acid (HHDPA) and 1-hydroxydodecylidene-1,1-diphosphonic acid (HDDPA), which were synthesized and characterized by elemental analysis and by FT-IR, 1H NMR, 31P NMR spectroscopy. In this paper, we propose a tentative assignment for the shifts of those two ligands and their specific complexes with uranium(VI). We carried out the extraction of uranium(VI) by HHDPA and HDDPA from [carbon tetrachloride + 2-octanol (v/v: 90%/10%)] solutions. Various factors such as contact time, pH, organic/aqueous phase ratio and extractant concentration were considered. The optimum conditions obtained were: contact time= 20 min, organic/aqueous phase ratio = 1, pH value = 3.0 and extractant concentration = 0.3M. The extraction yields are more significant in the case of the HHDPA which is equipped with a hydrocarbon chain, longer than that of the HDDPA. Logarithmic plots of the uranium(VI) distribution ratio vs. pHeq and the extractant concentration showed that the ratio of extractant to extracted uranium(VI) (ligand/metal) is 2:1. The formula of the complex of uranium(VI) with the HHDPA and the DHDPA is UO2(H3L)2 (HHDPA and DHDPA are denoted as H4L). A spectroscopic analysis has showed that coordination of uranium(VI) takes place via oxygen atoms.

Keywords: liquid-liquid extraction, uranium(vi), 1-hydroxyalkylidene-1, 1-diphosphonic acids, hhdpa, hddpa, aqueous solution

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Authors: Thamo Sutharssan, Diogo Montalvao, Wen-Chung Wang, Yong Chen, Claudia Pisac

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A combined heat and power (CHP) system is an efficient and clean way to generate power (electricity). Heat produced by the CHP system can be used for water and space heating. The CHP system which uses hydrogen as fuel produces zero carbon emission. Its’ efficiency can reach more than 80% whereas that of a traditional power station can only reach up to 50% because much of the thermal energy is wasted. The other advantages of CHP systems include that they can decentralize energy generation, improve energy security and sustainability, and significantly reduce the energy cost to the users. This paper presents the economic benefits of using a CHP system in the domestic environment. For this analysis, natural gas is considered as potential fuel as the hydrogen fuel cell based CHP systems are rarely used. UK government incentives for CHP systems are also considered as the added benefit. Results show that CHP requires a significant initial investment in return it can reduce the annual energy bill significantly. Results show that an investment may be paid back in 7 years. After the back period, CHP can run for about 3 years as most of the CHP manufacturers provide 10-year warranty.

Keywords: combined heat and power, clean energy, hydrogen fuel cell, economic analysis of CHP, zero emission

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Authors: Ke Yang, QiHan, Bauke de Veirs

Abstract:

This study addresses the need for coordinated management of natural resources in urban agglomeration. Using ecosystem services theory, The study explore the relationship between land use in the Beijing-Tianjin-Hebei (B-T-H) region and the Food-Water-Energy (F-W-E) nexus from 2000 to 2030. We assess ecosystem services using the InVEST: Habitat Quality (HQ), Water Yield (WY), Carbon Sequestration (CS), Soil Retention (SDR), and Food Production (FP). The study find an annual expansion of construction land alongside a significant decline in cultivated land. Additionally, HQ, CS, and per capita FP decline annually until 2020 and are expected to persist through 2030. In contrast, WY and SDR grow annually but may decline by 2030. Spearman coefficient analysis reveals synergies between HQ and CS, SDR and CS, and SDR and HQ, with trade-offs between CS and WY and HQ and WY. Utilizing the K-means clustering analysis method, we introduce county-based spatial planning for the F-W-E system, offering valuable insights and recommendations for sustainable resource management.

Keywords: food-water-energy (F-W-E), ecosystem services, trade-offs and synergies, ecosystem service bundle, county-based

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Authors: Alexandra Emmanuelle Membangbi, Jacky Njiki Bikoï, Esther Del-florence Moni Ndedi, Marie Joseph Nkodo Mindimi, Donatien Serge Mbaga, Elsa Nguiffo Makue, André Chris Mikangue Mbongue, Martha Mesembe, George Ikomey Mondinde, Eric Walter Perfura-yone, Sara Honorine Riwom Essama

Abstract:

Background: Tuberculosis (TB) is one of the top lethal infectious diseases worldwide. In recent years, interferon-γ (INF-γ) release assays (IGRAs) have been established as routine tests for diagnosing TB infection. However, produced INF-γ assessment failed to distinguish active TB (ATB) from latent TB infection (LTBI), especially in TB epidemic areas. In addition to IFN-γ, interleukin-2 (IL-2), another cytokine secreted by activated T cells, is also involved in immune response against Mycobacterium tuberculosis. The aim of the study was to assess the capacity of IFN-γ and IL2 to evaluate the therapeutic response of patients on anti-tuberculosis treatment. Material and Methods: We conducted a cross-sectional study in the Pneumonology Departments of the Jamot Hospital in Yaoundé between May and August 2021. After signed the informed consent, the sociodemographic data, as well as 5 mL of blood, were collected in the crook of the elbow of each participant. Sixty-one subjects were selected (n= 61) and divided into 4 groups as followed: group 1: resistant tuberculosis (n=13), group 2: active tuberculosis (n=19), group 3 cured tuberculosis (n=16), and group 4: presumed healthy persons (n=13). The cytokines of interest were determined using an indirect Enzyme-linked Immuno-Sorbent Assay (ELISA) according to the manufacturer's recommendations. P-values < 0.05 were interpreted as statistically significant. All statistical calculations were performed using SPSS version 22.0 Results: The results showed that men were more 14/61 infected (31,8%) with a high presence in active and resistant TB groups. The mean age was 41.3±13.1 years with a 95% CI = [38.2-44.7], the age group with the highest infection rate was ranged between 31 and 40 years. The IL-2 and INF-γ means were respectively 327.6±160.6 pg/mL and 26.6±13.0 pg/mL in active tuberculosis patients, 251.1±30.9 pg/mL and 21.4±9.2 pg/mL in patients with resistant tuberculosis, while it was 149.3±93.3 pg/mL and 17.9±9.4 pg/mL in cured patients, 15.1±8.4 pg/mL and 5.3±2.6 pg/mL in participants presumed healthy (p <0.0001). Significant differences in IFN-γ and IL-2 rates were observed between the different groups. Conclusion: Monitoring the serum levels of INF-γ and IL-2 would be useful to evaluate the therapeutic response of anti-tuberculosis patients, particularly in the both cytokines association case, that could improve the accuracy of routine examinations.

Keywords: antibiotic therapy, interferon gamma, interleukin 2, tuberculosis

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Authors: Prittesh Patel, Bhavika Patel, Ramar Krishnamurthy

Abstract:

Present study was conducted to isolate lactic acid bacteria (LAB) from Oreochromis niloticus and Nemipterus japonicus fish gut. The LAB isolated were confirmed through 16s rRNA sequencing. It was observed that isolated Lactococcus spp. were able to tolerate NaCl and bile acid up to certain range. The isolated Lactococcus spp. were also able to survive in acidic and alkaline conditions. Further agro-industrial waste like peels of pineapple, orange, lemon, sugarcane, pomegranate; sweet lemon was analyzed for their polysaccharide contents and prebiotic properties. In the present study, orange peels, sweet lemon peels, and pineapple peels give maximum indigestible polysaccharide. To evaluate synbiotic effect combination of probiotic and prebiotic were analyzed under in vitro conditions. Isolates Lactococcus garvieae R3 and Lactococcus sp. R4 reported to have better fermentation efficiency with orange, sweet lemon and pineapple compare to lemon, sugarcane and pomegranate. The different agro-industrial waste evaluated in this research resulted in being a cheap and fermentable carbon source by LAB.

Keywords: agro-industrial waste, lactic acid bacteria, prebiotic, probiotic, synbiotic

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Authors: Achraf Al Faraj, Asma Sultana Shaik, Baraa Al Sayed

Abstract:

Specific and effective targeting of drug delivery systems (DDS) to cancerous sites remains a major challenge for a better diagnostic and therapy. Recently, SWCNTs with their unique physicochemical properties and the ability to cross the cell membrane show promising in the biomedical field. The purpose of this study was first to develop a biocompatible iron oxide tagged SWCNTs as diagnostic nanoprobes to allow their noninvasive detection using MRI and their preferential targeting in a breast cancer murine model by placing an optimized flexible magnet over the tumor site. Magnetic targeting was associated to specific antibody-conjugated SWCNTs active targeting. The therapeutic efficacy of doxorubicin-conjugated SWCNTs was assessed, and the superiority of diffusion-weighted (DW-) MRI as sensitive imaging biomarker was investigated. Short Polyvinylpyrrolidone (PVP) stabilized water soluble SWCNTs were first developed, tagged with iron oxide nanoparticles and conjugated with Endoglin/CD105 monoclonal antibodies. They were then conjugated with doxorubicin drugs. SWCNTs conjugates were extensively characterized using TEM, UV-Vis spectrophotometer, dynamic light scattering (DLS) zeta potential analysis and electron spin resonance (ESR) spectroscopy. Their MR relaxivities (i.e. r1 and r2*) were measured at 4.7T and their iron content and metal impurities quantified using ICP-MS. SWCNTs biocompatibility and drug efficacy were then evaluated both in vitro and in vivo using a set of immunological assays. Luciferase enhanced bioluminescence 4T1 mouse mammary tumor cells (4T1-Luc2) were injected into the right inguinal mammary fat pad of Balb/c mice. Tumor bearing mice received either free doxorubicin (DOX) drug or SWCNTs with or without either DOX or iron oxide nanoparticles. A multi-pole 10x10mm high-energy flexible magnet was maintained over the tumor site during 2 hours post-injections and their properties and polarity were optimized to allow enhanced magnetic targeting of SWCNTs toward the primary tumor site. Tumor volume was quantified during the follow-up investigation study using a fast spin echo MRI sequence. In order to detect the homing of SWCNTs to the main tumor site, susceptibility-weighted multi-gradient echo (MGE) sequence was used to generate T2* maps. Apparent diffusion coefficient (ADC) measurements were also performed as a sensitive imaging biomarker providing early and better assessment of disease treatment. At several times post-SWCNT injection, histological analysis were performed on tumor extracts and iron-loaded SWCNT were quantified using ICP-MS in tumor sites, liver, spleen, kidneys, and lung. The optimized multi-poles magnet revealed an enhanced targeting of magnetic SWCNTs to the primary tumor site, which was found to be much higher than the active targeting achieved using antibody-conjugated SWCNTs. Iron-loading allowed their sensitive noninvasive tracking after intravenous administration using MRI. The active targeting of doxorubicin through magnetic antibody-conjugated SWCNTs nanoprobes was found to considerably decrease the primary tumor site and may have inhibited the development of metastasis in the tumor-bearing mice lung. ADC measurements in DW-MRI were found to significantly increase in a time-dependent manner after the injection of DOX-conjugated SWCNTs complexes.

Keywords: single-walled carbon nanotubes, nanomedicine, magnetic resonance imaging, cancer diagnosis and therapy

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Authors: Magali Mari, Misha Muller

Abstract:

The present study’s objectives were to determine how diverse implicit stereotypes affect the processing of written information and linguistic inferential processes, such as presupposition accommodation. When reading a text, one constructs a representation of the described situation, which is then updated, according to new outputs and based on stereotypes inscribed within society. If the new output contradicts stereotypical expectations, the representation must be corrected, resulting in longer reading times. A similar process occurs in cases of linguistic inferential processes like presupposition accommodation. Presupposition accommodation is traditionally regarded as fast, automatic processing of background information (e.g., ‘Mary stopped eating meat’ is quickly processed as Mary used to eat meat). However, very few accounts have investigated if this process is likely to be influenced by domains of social cognition, such as implicit stereotypes. To study the effects of implicit stereotypes on presupposition accommodation, adults were recorded while they read sentences in French, combining two methods, an eye-tracking task and a classic self-paced reading task (where participants read sentence segments at their own pace by pressing a computer key). In one condition, presuppositions were activated with the French definite articles ‘le/la/les,’ whereas in the other condition, the French indefinite articles ‘un/une/des’ was used, triggering no presupposition. Using a definite article presupposes that the object has already been uttered and is thus part of background information, whereas using an indefinite article is understood as the introduction of new information. Two types of stereotypes were under examination in order to enlarge the scope of stereotypes traditionally analyzed. Study 1 investigated gender stereotypes linked to professional occupations to replicate previous findings. Study 2 focused on nationality-related stereotypes (e.g. ‘the French are seducers’ versus ‘the Japanese are seducers’) to determine if the effects of implicit stereotypes on reading are generalizable to other types of implicit stereotypes. The results show that reading is influenced by the two types of implicit stereotypes; in the two studies, the reading pace slowed down when a counter-stereotype was presented. However, presupposition accommodation did not affect participants’ processing of information. Altogether these results show that (a) implicit stereotypes affect the processing of written information, regardless of the type of stereotypes presented, and (b) that implicit stereotypes prevail over the superficial linguistic treatment of presuppositions, which suggests faster processing for treating social information compared to linguistic information.

Keywords: eye-tracking, implicit stereotypes, reading, social cognition

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Authors: Gaoyuan Wang, Tian Chen, Junnan Liu

Abstract:

Facing a period of major change that’s rarely seen in a century, China formulates the 14th Five-Year Plan and places emphasis on promoting high-quality development. In this context, the overall urban design has become a crucial and systematic tool for high-quality urban development. However, there are bottlenecks in the nature definition, content scope and transmission mechanisms of the current overall urban design in China. The paper interprets the emerging demands of the 14th Five-Year Plan on urban design in terms of new value-quality priority, new dynamic-space performance, new target-region coordination and new path-refined governance. Based on the new trend and appeal, the multi-dimensional thinking integrated with the major tasks of urban design are proposed accordingly, which is the biomass thinking in ecological, production and living element, the strategic thinking in spatial structure, the systematic thinking in the cityscape, the low-carbon thinking in urban form, the governance thinking in public space, the user thinking in design implementation. The paper explores the possibility of transforming the value thinking and technical system of urban design in China and provides a breakthrough path for the urban planning and design industry to better respond to the propositions of the country’s 14th Five-Year Plan.

Keywords: China’s 14th five-year plan, overall urban design, urban design thinking, transformation of urban design

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Authors: Yiyuan David Hu, Alex Lindqwister, Samuel B. Klein, Karen Moodie, Norman A. Paradis

Abstract:

Introduction: Pseudo-Pulseless Electrical Activity (p-PEA) is a lifeless form of profound cardiac shock characterized by measurable cardiac mechanical activity without clinically detectable pulses. Patients in pseudo-PEA carry different prognoses than those in true PEA and may require different therapies. End-tidal carbon dioxide (ET-CO2) is a reliable indicator of the return of spontaneous circulation (ROSC) in ventricular fibrillation and true-PEA but has not been studied p-PEA. Hypothesis: ET-CO2 can be used as an independent indicator of ROSC in p-PEA resuscitation. Methods: 30kg female swine (N = 14) under intravenous anesthesia were instrumented with aortic and right atrial micromanometer pressure. ECG and ET-CO2 were measured continuously. p-PEA was induced by ventilation with 6% oxygen in 94% nitrogen and was defined as a systolic Ao less than 40 mmHg. The statistical relationships between ET-CO2 and ROSC are reported. Results: ET-CO2 during resuscitation strongly correlated with ROSC (Figure 1). Mean ET-CO2 during p-PEA was 28.4 ± 8.4, while mean ET-CO2 in ROSC for 100% O2 cohort was 42.2 ± 12.6 (p < 0.0001), mean ET-CO2 in ROSC for 100% O2 + CPR was 33.0 ± 15.4 (p < 0.0001). Analysis of slope was limited to one minute of resuscitation data to capture local linearity; assessment began 10 seconds after resuscitation started to allow the ventilator to mix 100% O2. Pigs who would recover with 100% O2 had a slope of 0.023 ± 0.001, oxygen + CPR had a slope of 0.018 ± 0.002, and oxygen + CPR + epinephrine had a slope of 0.0050 ± 0.0009. Conclusions: During resuscitation from porcine hypoxic p-PEA, a rise in ET-CO2 is indicative of ROSC.

Keywords: ET-CO2, resuscitation, capnography, pseudo-PEA

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Authors: Gopi Kerekere Rangaraju, Madhu Puttegowda

Abstract:

Natural fibres composites include coir, jute, bagasse, cotton, bamboo, and hemp. Natural fibers come from plants. These fibers contain lingo cellulose in nature. Natural fibers are eco-friendly; lightweight, strong, renewable, cheap, and biodegradable. The natural fibers can be used to reinforce both thermosetting and thermoplastic matrices. Thermosetting resins such as epoxy, polyester, polyurethane, and phenolic are commonly used composites requiring higher performance applications. They provide sufficient mechanical properties, in particular, stiffness and strength at acceptably low-price levels. Recent advances in natural fibers development are genetic engineering. The composites science offers significant opportunities for improved materials from renewable resources with enhanced support for global sustainability. Natural fibers composites are attractive to industry because of their low density and ecological advantages over conventional composites. These composites are gaining importance due to their non-carcinogenic and bio-degradable nature. Natural fibers composites are a very costeffective material, especially in building and construction, packaging, automobile and railway coach interiors, and storage devices. These composites are potential candidates for the replacement of high- cost glass fibers for low load bearing applications. Natural fibers have the advantages of low density, low cost, and biodegradability

Keywords: PMC, basalt, coir, carbon fibers

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Authors: Yasar N. Kavil, Yasser A. Shaban, Radwan K. Al Farawati, Mohamed I. Orif, Shahed U. M. Khanc

Abstract:

Photocatalytic way of reduction of CO₂ in polluted seawater into chemical fuel, methanol, was successfully gained over Cu/C-co-doped TiO₂ nanoparticles under UV and natural sunlight. A homemade stirred batch annular reactor was used to carry out the photocatalytic reduction experiments. Photocatalysts with various Cu loadings (0, 0.5, 1, 3, 5 and 7 wt.%) were synthesized by the sol-gel procedure and were characterized by XRD, SEM, UV–Vis, FTIR, and XPS. The photocatalytic production of methanol was promoted by the co-doping with C and Cu into TiO₂. This improvement was attributed to the modification of bandgap energy and the hindrance of the charges recombination. The polluted seawater showing the yield depended on its background hydrographic parameters. We assessed two types of polluted seawater system, the observed yield was 2910 and 990 µmol g⁻¹ after 5 h of illumination under UV and natural sunlight respectively in system 1 and the corresponding yield in system 2 was 2250 and 910 µmol g⁻¹ after 5 h of illumination. The production of methanol in the case of oxygen-depleted water was low, this is mainly attributed to the competition of methanogenic bacteria over methanol production. The results indicated that the methanol yield produced by Cu-C/TiO₂ was much higher than those of carbon-modified titanium oxide (C/TiO₂) and Degussa (P25-TiO₂). Under the current experimental condition, the optimum loading was achieved by the doping of 3 wt % of Cu. The highest methanol yield was obtained over 1 g L-1 of 3wt% Cu/C-TiO₂.

Keywords: CO₂ photoreduction, copper, Cu/C-co-doped TiO₂, methanol, seawater

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Authors: Nikhil John Kollannur, Dali Naidu Arnepalli

Abstract:

Most of the surface related phenomena in the case of fine-grained soil are attributed to their unique surface charge properties and specific surface area. The temporal variations in soil behavior, to some extent, can be credited to the changes in these properties. Among the multitude of factors that affect the charge and surface area of clay minerals, the inherent system chemistry occupies the cardinal position. The impact is more profound when the chemistry change is manifested in terms of the system pH. pH plays a significant role by modifying the edge charges of clay minerals and facilitating mineral dissolution. Hence there is a need to address the variations in physical and charge properties of fine-grained soils treated over a range of acidic as well as alkaline conditions. In the present study, three soils (two soils commercially procured and one natural soil) exhibiting distinct mineralogical compositions are subjected to different pH environment over a range of 2 to 13. The soil-solutions prepared at a definite liquid to solid ratio are adjusted to the required pH value by adding measured quantities of 0.1M HCl/0.1M NaOH. The studies are conducted over a range of interaction time, varying from 1 to 96 hours. The treated soils are then analyzed for their physical properties in terms of specific surface area and particle size characteristics. Further, modifications in surface morphology are evaluated from scanning electron microscope (SEM) imaging. Changes in the surface charge properties are assessed in terms of zeta potential measurements. Studies show significant variations in total surface area, probably because of the dissolution of clay minerals. This observation is further substantiated by the morphological analysis with SEM imaging. The zeta potential measurements on soils indicate noticeable variation upon pH treatment, which is partially ascribed to the modifications in the pH-dependant edge charges and partially due to the clay mineral dissolution. The results provide valuable insight into the role of pH in a clay-electrolyte system upon surface related phenomena such as species adsorption, fabric modification etc.

Keywords: acid and alkali treatment, mineral dissolution , specific surface area, zeta potential

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