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Experimental Study of Selective Batch Bio-Adsorption for the Removal of Dyes in Industrial Textile Effluents 被引量:2
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作者 Zakaria Laggoun Amel Khalfaoui +3 位作者 Kerroum Derbal Amira Fadia Ghomrani Abderrezzaq Benalia Antonio Pizzi 《Journal of Renewable Materials》 2025年第1期127-146,共20页
This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of t... This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of two dyes(TR+CG-H3G).The Cockle Shell(CS)was used as a natural bio-adsorbent.The characterizations of CS were investigated by Fourier transform infrared(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDX)and Brunauer–Emmett–Teller(BET).The adsorption potential of Cockle Shells was tested in two cases(single and binary system)and determined by:contact time(0–60 min),bio-adsorption dose(3–15 g/L),initial concentration(10–300 mg/L),temperature(22–61°C)and pH solution(2–12).The study of bio-adsorption(equilibrium and kinetics)was conducted at 22°C.The kinetic studies demon-strated that a pseudo-second-order adsorption mechanism had a good correlation coefficient(R2≥0.999).The Langmuir isotherm modeling provided a well-defined description of TR and CG-H3G bio-adsorption on cockle shells,exhibiting maximum capacities of 29.41 and 3.69 mg/g respectively at 22°C.The thermodynamic study shows that the reaction between the TR,CG-H3G dyes molecules and the bio-adsorbent is exothermic,spontaneous in the range of 22–31°C with the aleatory character decrease at the solid-liquid interface.The study of selectivity in single and binary systems has been performed under optimal operating conditions using the industrial textile rejection pH(pH=6.04).CG-H3G dye is found to have a higher selectivity than TR in single(0–60 min)and binary systems with a range of 6–45 min,as shown by the selectivity measurement.It was discovered that CS has the capability to remove both CG-H3G and TR dyes in both simple and binary systems,making it a superior bio-adsorbent. 展开更多
关键词 Cockle shells bio-adsorption binary system dyes cibacron green terasil red selectivity
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Optimization of the Pretreatment of the Mixture of Cassava Peelings and Pineapple Fibers Using Response Surface Methodology and a Process Simulator for the Bioethanol Production
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作者 Paul Nestor Djomou Djonga George Elambo Nkeng +2 位作者 Madjoyogo Hervé Sirma Ahmat Tom Thierry Tchamba Tchuidjang 《Energy and Power Engineering》 2024年第2期79-96,共18页
The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production ... The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production of bioethanol remains a challenge given the crystallinity of cellulose and the presence of the complex. The pretreatment aimed to solubilize the lignin fraction and to make cellulose more accessible to the hydrolytic enzymes, was done using the organosolv process. A mathematical modeling was performed to point out the effect of the temperature on the kinetics of the release of the reducing sugars during the pretreatment. Two mathematical model was used, SAEMAN’s model and Response surface methodology. The first show that the kinetic parameters of the hydrolysis of the cellulose and reducing sugar are: 0.05089 min<sup>-1</sup>, 5358.1461 J·mol<sup>-1</sup>, 1383.03691 min<sup>-1</sup>, 51577.6100 J·mol<sup>-1</sup> respectively. The second model was used. Temperature is the factor having the most positive influence whereas, ethanol concentration is not an essential factor. To release the maximum, an organosolv pre-treatment of this sub-strate should be carried out at 209.08°C for 47.60 min with an ethanol-water ratio of 24.02%. Organosolv pre-treatment is an effective process for delignification of the lignocellulosic structure. 展开更多
关键词 BIOETHANOL Cassava Peeling Pineapple Fibers Organosolv Process and Optimization
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Investigation of physico-chemical properties and microbial community during poultry manure co-composting process 被引量:6
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作者 Omar Farah Nadia Loo Yu Xiang +3 位作者 Lee Yei Lie Dzulkornain Chairil Anuar Mohammed P.Mohd Afandi Samsu Azhari Baharuddin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第2期81-94,共14页
Co-composting of poultry manure and rubber wood sawdust was performed with the ratio of 2:1(V/V) for a period of 60 days. An investigation was carried out to study the extracellular enzymatic activities and structu... Co-composting of poultry manure and rubber wood sawdust was performed with the ratio of 2:1(V/V) for a period of 60 days. An investigation was carried out to study the extracellular enzymatic activities and structural degradation utilizing Fourier transform infrared spectroscopy(FT-IR), thermogravimetry and differential thermal analysis(TG/DTA)and scanning electron microscopy(SEM). The microbial succession was also determined by using denaturing gel gradient electrophoresis(DGGE). The compost was able to reach its highest temperature of 71°C at day 3 and stabilized between 30 and 40°C for 8 weeks.CMCase, FPase and β-glucosidase acted synergistically in order to degrade the cellulosic substrate. The xylanase activities increased gradually during the composting and reached the peak value of 11.637 U/g on day 35, followed by a sharp decline. Both Li P and Mn P activities reached their peak values on day 35 with 0.431 and 0.132 U/g respectively. The FT-IR spectra revealed an increase in aromaticity and a decrease in aliphatic compounds such as carbohydrates as decomposition proceeded. TGA/DTG data exhibited significant changes in weight loss in compost samples, indicating degradation of organic matter. SEM micrographs showed higher amounts of parenchyma exposed on the surface of rubber wood sawdust at day 60, showing significant degradation. DGGE and 16 S r DNA analyses showed that Burkholderia sp., Pandoraea sp., and Pseudomonas sp. were present throughout the composting process. Ornithinibacillus sp. and Castellaniella ginsengisoli were only found in the initial stage of the composting, while different strains of Burkholderia sp. also occurred in the later stage of composting. 展开更多
关键词 COMPOSTING Poultry manure CELLULOSE Denaturing gel gradient ELECTROPHORESIS Microbial community
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Use of ionic liquid in leaching process of brass wastes for copper and zinc recovery 被引量:3
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作者 Ayfer Kilicarslan Muhlis Nezihi Saridede +1 位作者 Srecko Stopic Bernd Friedrich 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第2期138-143,共6页
Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid (IL) 1-butyl-3-methyl-imi-dazolium hydrogen sulfate ([bmim]HSO4) at ambient pressure in the presence of hy... Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid (IL) 1-butyl-3-methyl-imi-dazolium hydrogen sulfate ([bmim]HSO4) at ambient pressure in the presence of hydrogen peroxide (H2O2) and potassium peroxymonosulfate (oxone) as the oxidants. Parameters affecting leaching efficiency, such as dissolution time, IL concentration, and oxidizing agent addition, were investigated. The results show that [bmim]HSO4 is an efficient IL for the brass ash leaching, providing the dissolution efficiencies of 99%for Zn and 24.82%for Cu at a concentration of 50vol%[bmim]HSO4 in the aqueous solution without any oxidant. However, more than 99%of zinc and 82%of copper are leached by the addition of 50vol%H2O2 to the [bmim]HSO4 solution. Nevertheless, the oxone does not show the promising oxidant behavior in leaching using [bmim]HSO4. 展开更多
关键词 leaching recovery COPPER zinc ionic liquids OXIDANTS
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Isolation and activation of collagenase from fish processing waste 被引量:4
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作者 Said M. Daboor Suzanne M. Budge +2 位作者 Abdel E. Ghaly Marianne S. Brooks Deepika Dave 《Advances in Bioscience and Biotechnology》 2012年第3期191-203,共13页
Collagenase was isolated from fish waste (a mixture of haddock, herring, ground fish and flounder) using a Tris-buffer system. The proteins in the crude extract were precipitated using ammonium sulfate (40% - 80%) and... Collagenase was isolated from fish waste (a mixture of haddock, herring, ground fish and flounder) using a Tris-buffer system. The proteins in the crude extract were precipitated using ammonium sulfate (40% - 80%) and purified with gel-filtration chromatography using Sephadex G-100. The results showed that the collagenase enzyme was produced as a latent enzyme and was activated with bovine trypsin and potassium thiocyanate (KSCN). The enzyme activity was affected by pH and temperature. Optimal enzyme activities were found at 35?C and a pH of 7.5 when insoluble collagene type I was used as substrate and the liberated amino acids were measured in relation to L-leucine in the presence of ninhydrin. The enzyme activity was completely inhibited by the action of ethylenediaminetetraacetic acid (EDTA) suggesting that the collagenase enzyme isolated from the fish waste is a metalloproteinase enzyme requiring metal ions for enzyme activity. Dialysis against KSCN decreased the enzyme total activity and increased its specific activity. Sodium dodecyl sulphate polyacryla-mide gel electrophoresis (SDS-PAGE) indicated that the purified procollagenase enzyme have only one band at molecular weight of 50 kilodaltons (kDa). When the enzyme was cleaved with trypsin, it was found to consist of two subunits: a large unit with a molecular weight of 50 kDa and a small unit with a molecular weight of 10 kDa. 展开更多
关键词 Fish WASTE COLLAGENASE ENZYME Extraction PURIFICATION INHIBITORS ACTIVATORS
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Development and Validation of Stability Indicating RP-HPLC Method on Core Shell Column for Determination of Degradation and Process Related Impurities of Apixaban—An Anticoagulant Drug 被引量:2
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作者 Shashikant B. Landge Sanjay A. Jadhav +3 位作者 Sunil B. Dahale Pavankumar V. Solanki Saroj R. Bembalkar Vijayavitthal T. Mathad 《American Journal of Analytical Chemistry》 2015年第6期539-550,共12页
A rapid, specific, sensitive, and precise reverse-phase HPLC method for the quantitative determination of process related and degradation impurities of Apixaban, an anticoagulant drug is described. The developed RP-HP... A rapid, specific, sensitive, and precise reverse-phase HPLC method for the quantitative determination of process related and degradation impurities of Apixaban, an anticoagulant drug is described. The developed RP-HPLC method was successfully applied to the analysis of both Apixaban drug substance and drug product. The chromatographic separation was achieved on a Sigma-Aldrich’s Ascentis Express&reg;C18 (4.6 mm × 100 mm, 2.7 μ) HPLC column with a runtime of 40 min. Mobile phase-A and mobile phase-B were phosphate buffer and acetonitrile respectively. The column oven temperature was set at 35&deg;C and photodiode array detector was set at 225 nm. Nine process related impurities (Imp-1 to Imp-9) have been detected in test sample of Apixaban by using newly developed RP-HPLC method. Forced degradation study was carried out under acidic, alkaline, oxidative, photolytic and thermal conditions to demonstrate the stability-indicating nature of the developed RP-HPLC method. The developed method was validated as per ICH guideline and found to be specific, precise, sensitive and robust. 展开更多
关键词 APIXABAN CORE-SHELL HPLC COLUMNS RSD and VALIDATION Stability Indicating
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Development and Validation of Stability Indicating Rapid RP-LC Method for Determination of Process and Degradation Related Impurities of Apremilast, an Anti-Inflammatory Drug 被引量:1
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作者 Shashikant B. Landge Sunil B. Dahale +3 位作者 Sanjay A. Jadhav Pavankumar V. Solanki Saroj R. Bembalkar Vijayavitthal T. Mathad 《American Journal of Analytical Chemistry》 2017年第6期380-394,共15页
A new, specific, rapid and stability indicating reversed phase liquid chro-matographic (RP-LC) method for the determination of process related and degradation related impurities of Apremilast has been developed and va... A new, specific, rapid and stability indicating reversed phase liquid chro-matographic (RP-LC) method for the determination of process related and degradation related impurities of Apremilast has been developed and validated. The degradation study performed in acid, base, oxidative, photolytic, and thermal stressed conditions. Eight process related impurities (Imp-1 to Imp-8) in test sample of Apremilast have been detected by developed RP-LC method. The good chromatographic resolution between the peaks of process related impurities, degradation impurities and Apremilast has been achieved on a Synergi Max-RP 80 A (150 × 4.6 mm ID), 4 μ column. The process and degradation related impurities were characterized by mass spectrometry, 1H NMR and FT-IR spectral data. The method was validated as per ICH guideline and found to be specific, rapid, and stability indicating. The proposed RP-PLC method was successfully applied to the analysis of drug substance samples of Apremilast. 展开更多
关键词 Apremilast Stability Indicating RP-LC PDE4 INHIBITOR FORCED DEGRADATION
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An Efficient and Provably Secure SM2 Key-Insulated Signature Scheme for Industrial Internet of Things 被引量:1
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作者 Senshan Ouyang Xiang Liu +3 位作者 Lei Liu Shangchao Wang Baichuan Shao Yang Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期903-915,共13页
With the continuous expansion of the Industrial Internet of Things(IIoT),more andmore organisations are placing large amounts of data in the cloud to reduce overheads.However,the channel between cloud servers and smar... With the continuous expansion of the Industrial Internet of Things(IIoT),more andmore organisations are placing large amounts of data in the cloud to reduce overheads.However,the channel between cloud servers and smart equipment is not trustworthy,so the issue of data authenticity needs to be addressed.The SM2 digital signature algorithm can provide an authentication mechanism for data to solve such problems.Unfortunately,it still suffers from the problem of key exposure.In order to address this concern,this study first introduces a key-insulated scheme,SM2-KI-SIGN,based on the SM2 algorithm.This scheme boasts strong key insulation and secure keyupdates.Our scheme uses the elliptic curve algorithm,which is not only more efficient but also more suitable for IIoT-cloud environments.Finally,the security proof of SM2-KI-SIGN is given under the Elliptic Curve Discrete Logarithm(ECDL)assumption in the random oracle. 展开更多
关键词 KEY-INSULATED SM2 algorithm digital signature Industrial Internet of Things(IIoT) provable security
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Process Characterization of the Transesterification of Rapeseed Oil to Biodiesel Using Design of Experiments and Infrared Spectroscopy
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作者 Tobias Drieschner Andreas Kandelbauer +1 位作者 Bernd Hitzmann Karsten Rebner 《Journal of Renewable Materials》 SCIE EI 2023年第4期1643-1660,共18页
For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the proc... For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality.The present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor set-up.To this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are investigated.The optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction yield.The quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares regression.The data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of 0.9608.Thus,we applied a PAT approach to generate further insight into this established industrial process. 展开更多
关键词 Process analytical technology TRANSESTERIFICATION design of experiment attenuated total reflection infrared spectroscopy partial least square regression
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Potential use of Ulva intestinalis-derived biochar adsorbing phosphate ions in the cultivation of winter wheat Tristicum aestivum 被引量:1
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作者 Natalia Niedzbała Ewa Lorenc-Grabowska +4 位作者 Piotr Rutkowski Jacek Chęcmanowski Anna Szymczycha-Madeja Maja Wełna Izabela Michalak 《Bioresources and Bioprocessing》 2024年第1期371-394,共24页
In this work,the properties of biochar produced from green macroalga Ulva intestinalis by pyrolysis were studied at temperatures of 300,500,and 700°C.This biochar was characterized in terms of multielemental comp... In this work,the properties of biochar produced from green macroalga Ulva intestinalis by pyrolysis were studied at temperatures of 300,500,and 700°C.This biochar was characterized in terms of multielemental composition,BET surface area,total pore volume,and biosorption properties toward phosphate ions.Biochar produced at 700°C-25 m2/g had the highest surface area.The kinetics and isotherms of sorption processes of phosphate ions as sorbate by these sorbents were investigated.Modified biochar was able to remove 84.3%of phosphate ions from wastewater,whereas non-modified biochar-only 40.6%.Hence,biochar enriched with phosphate ions can serve as a valuable soil amendment.Pot experiments performed on winter wheat(Triticum aestivum)with a 3%addition of dry Ulva intestinalis,pristine biochar,and Mg-modified biochar enriched with phosphate ions showed that these amendments stimulated plant growth(length and fresh weight of plants)as well as enlarging the chlorophyll content in leaves.Our results indicate that the production of biochar(pristine and Mg-impregnated)is a sustainable option to valorize the biomass of seaweeds,and to recycle phosphorus from wastewater. 展开更多
关键词 Green seaweed Pyrolysis BIOCHAR Phosphate ions Wastewater treatment Soil additives
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Recent advances in heterogeneous catalysis of solar-driven carbon dioxide conversion
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作者 Jun Xu Farzaneh Arabpour Roghabadi +4 位作者 Ying Luo Vahid Ahmadi Qian Wang Zheng Wang Hong He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第6期165-182,共18页
Solar-driven carbon dioxide(CO_(2))conversion including photocatalytic(PC),photoelectrochemical(PEC),photovoltaic plus electrochemical(PV/EC)systems,offers a renewable and scalable way to produce fuels and high-value ... Solar-driven carbon dioxide(CO_(2))conversion including photocatalytic(PC),photoelectrochemical(PEC),photovoltaic plus electrochemical(PV/EC)systems,offers a renewable and scalable way to produce fuels and high-value chemicals for environment and energy sustainability.This review summarizes the basic fundament and the recent advances in the field of solar-driven CO_(2)conversion.Expanding the visible-light absorption is an important strategy to improve solar energy conversion efficiency.The separation and migration of photogenerated charges carriers to surface sites and the surface catalytic processes also determine the photocatalytic performance.Surface engineering including co-catalyst loading,defect engineering,morphology control,surface modification,surface phase junction,and Z-scheme photocatalytic system construction,have become fundamental strategies to obtain high-efficiency photocatalysts.Similar to photocatalysis,these strategies have been applied to improve the conversion efficiency and Faradaic efficiency of typical PEC systems.In PV/EC systems,the electrode surface structure and morphology,electrolyte effects,and mass transport conditions affect the activity and selectivity of electrochemical CO_(2)reduction.Finally,the challenges and prospects are addressed for the development of solar-driven CO_(2)conversion system with high energy conversion efficiency,high product selectivity and stability. 展开更多
关键词 Solar-driven CO_(2)reduction Photocatalytic system Photoelectrochemical system Photovoltaic plus electrochemical system Surface/interface engineering
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Purification of Produced Water from a Sour Oilfield in South Kuwait. 1. Oil-Water Separation and Industrial Salt Production
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作者 Feras Al Salem Hessa Al Shamsi +5 位作者 Mariam Mohammed Abdulla Alaryani Basmalah Abdelazim Mohamed Khalaf Omnia Elsheikh Vijo Poulose Yosef Al Jasem Thies Thiemann 《Journal of Water Resource and Protection》 CAS 2024年第2期156-180,共25页
Produced water from an oil extraction site in South Kuwait was sampled after primary oil – water separation had been carried out. The produced water was filtered through a mixture of activated charcoal and esterified... Produced water from an oil extraction site in South Kuwait was sampled after primary oil – water separation had been carried out. The produced water was filtered through a mixture of activated charcoal and esterified cellulosic material gained from spent coffee grounds as a tertiary adsorption treatment. The earth-alkaline metal ions and heavy metals were separated from the de-oiled produced water by addition of either sodium or potassium hydroxide in the presence of carbon dioxide or by direct addition of solid sodium carbonate. The resulting filtrate gave salt of industrial purity upon selective crystallization on evaporation. 展开更多
关键词 Produced Water Oil and Gas Adsorption Filtration CRYSTALLIZATION
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Application of Plant-Based Coagulants and Their Mechanisms in Water Treatment:A Review
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作者 Abderrezzaq Benalia Kerroum Derbal +3 位作者 Zahra Amrouci Ouiem Baatache Amel Khalfaoui Antonio Pizzi 《Journal of Renewable Materials》 EI CAS 2024年第4期667-698,共32页
This review describes the mechanisms of natural coagulants.It provides a good understanding of the two key processes of coagulation-flocculation:adsorption and charge neutralization,as well as adsorption and bridging.... This review describes the mechanisms of natural coagulants.It provides a good understanding of the two key processes of coagulation-flocculation:adsorption and charge neutralization,as well as adsorption and bridging.Various factors have influence the coagulation/flocculation process,including the effect of pH,coagulant dosage,coagulant type,temperature,initial turbidity,coagulation speed,flocculation speed,coagulation and flocculation time,settling time,colloidal particles,zeta potential,the effects of humic acids,and extraction density are explained.The bio-coagulants derived from plants are outlined.The impact of organic coagulants on water quality,focusing on their effects on the physicochemical parameters of water,heavy metals removal,and bacteriological water quality,is examined.The methods of extraction and purification of plant-based coagulants,highlighting techniques such as solvent extraction and ultrasonic extraction,are discussed.It also examines the parameters that influence these processes.The methods and principles of purification of coagulating agents,including dialysis,freeze-drying,ion exchange,electrophoresis,filtration,and centrifugation,are listed.Finally,it evaluates the sustainability of natural coagulants,focusing on the environmental,technical,and economic aspects of their use.At the end of this review,the readers should have a comprehensive understanding of the mechanisms,selection,extraction,purification,and sustainability of plant-based natural coagulants in water treatment. 展开更多
关键词 Bio-coagulants coagulating agents extraction water treatment
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Exergy Analysis of a Solar Vapor Compression Refrigeration System Using R1234ze(E)as an Environmentally Friendly Replacement of R134a
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作者 Zakaria Triki Ahmed Selloum +6 位作者 Younes Chiba Hichem Tahraoui Dorsaf Mansour Abdeltif Amrane Meriem Zamouche Mohammed Kebir Jie Zhang 《Frontiers in Heat and Mass Transfer》 EI 2024年第4期1107-1128,共22页
Refrigeration plays a significant role across various aspects of human life and consumes substantial amounts of electrical energy.The rapid advancement of green cooling technology presents numerous solar-powered refri... Refrigeration plays a significant role across various aspects of human life and consumes substantial amounts of electrical energy.The rapid advancement of green cooling technology presents numerous solar-powered refrigeration systems as viable alternatives to traditional refrigeration equipment.Exergy analysis is a key in identifying actual thermodynamic losses and improving the environmental and economic efficiency of refrigeration systems.In this study exergy analyze has been conducted for a solar-powered vapor compression refrigeration(SP-VCR)system in the region of Gharda颽(Southern Algeria)utilizing R1234ze(E)fluid as an eco-friendly substitute for R134a refrigerant.A MATLAB-based numerical model was developed to evaluate losses in different system components and the exergy efficiency of the SP-VCR system.Furthermore,a parametric study was carriedout to analyze the impact of various operating conditions on the system’s exergy destruction and efficiency.The obtained results revealed that,for both refrigerants,the compressor exhibited the highest exergy destruction,followed by the condenser,expansion valve,and evaporator.However,the system using R1234ze(E)demonstrated lower irreversibility compared to that using R134a refrigerant.The improvements made with R1234ze are 71.95%for the compressor,39.13%for the condenser,15.38%for the expansion valve,5%for the evaporator,and 54.76%for the overall system,which confirm the potential of R1234ze(E)as a promising alternative to R134a for cooling applications. 展开更多
关键词 Solar cooling vapor compression refrigeration eco-friendly refrigerant thermodynamic losses exergy analysis
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Experimental study and thermodynamic modeling of CO_(2)+CH_(4) gas mixture hydrate phase equilibria for gas separation efficiency
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作者 Ali Moshfegh Haghighi Ali Haghtalab 《Natural Gas Industry B》 2024年第4期432-442,共11页
Gas separation is a critical application of gas hydrates,and accurately predicting separation performance is crucial.In this study,we used thermodynamic calculations to predict the equilibrium phase of gas hydrates fo... Gas separation is a critical application of gas hydrates,and accurately predicting separation performance is crucial.In this study,we used thermodynamic calculations to predict the equilibrium phase of gas hydrates for various mole fractions of CO_(2)+CH_(4)gas mixtures.We also determined the mole fraction of each gas component trapped within the hydrate clathrate.To predict the equilibrium points,we used the SoaveeRedlicheKwong(SRK)equation of state for the gas phase,the nonrandom two-liquid(NRTL)model for the liquid phase,and the CheneGuo model for the hydrate phase.We modified the hydrate fugacity formula and introduced a new function to improve the accuracy of the CheneGuo model.By incorporating experimental equilibrium results from our study and another study,we developed a correlation based on gas mixture composition and temperature,resulting in highly accurate predictions.The use of this new correlation for hydrate fugacity calculation significantly improved precision,as evidenced by an average absolute deviation percent of calculated pressures(AADP)of 1.34%for pure CO_(2)and 1.25%for CH_(4).When considering the 27 data points of different CO_(2)+CH_(4)mixtures,the AADP%was 1.98%.To implement the model to predict equilibrium phases,we used the CheneGuo framework to determine the mole fraction of each gas component in the hydrate mixture.Interestingly,we discovered a linear correlation between the CO_(2)mole fraction in the hydrate and equilibrium pressure,with a slope of approximately 0.001 and a y-intercept of less than one,for all gas compositions.Therefore,we can conclude that low thermodynamic conditions(temperature and pressure)result in a high CO_(2)mole fraction in the hydrate phase and great separation efficiency. 展开更多
关键词 CO_(2) CH_(4) HYDRATE Gas separation Thermodynamic modeling NRTL SRK
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Extraction, Production and Quality Evaluation of Margarine from Oil Extracted from Waste Biomass Peels of Avocado and Virgin Coconut Oil, Using Chitosan from Reared Shells as Preservative
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作者 Suh-Ndale Svetlana Miyanui Pride Ndasi Ngwasiri +3 位作者 Wiyeh Claudette Bakisu Muala Noumo Thierry Ngangmou Wilson Agwanande Ambindei Martin Benoit Ngassoum 《Journal of Agricultural Chemistry and Environment》 2024年第1期142-168,共27页
The production and consumption of avocado pears generates tons of wastes, mainly the pear peels which are usually discarded, although they have been reported to contain important phyto-chemicals with biological activi... The production and consumption of avocado pears generates tons of wastes, mainly the pear peels which are usually discarded, although they have been reported to contain important phyto-chemicals with biological activities. The adverse health effect associated with the consumption of saturated lipid based foods has ignited research on reformulation of lipid based foods to eliminate Trans Fatty Acids (TFAs). This study was thus aimed at the extraction and characterization of oil from Avocado Peels (APO) and evaluation of the quality of margarine produced from it. Five verities of pear were used for oil extraction by soxhlet method and physiochemical, oxidative, functional and antioxidant characterization was done. Margarines were formulated using a central composite design using oil blends of APO and Virgin Coconut Oil (VCO) with an oil ratio of 10:90, 40:60, 70:30 respectively, varied blending speed, blending time, and chitosan concentration. Samples were characterized and the effect of process parameters on the physiochemical and functional properties of the margarine studied. Optimized conditions were used to produce samples for sensory evaluation. Color, spreadability, aroma, taste and general acceptability was evaluated using ranking difference test. The results showed that the yield, density, and iodine values of APOs oils ranged from 14.91 ± 0.18 to 11.76 ± 0.46;0.93 ± 0.001 to 0.99 ± 0.1;46.63 ± 1.70 to 52.4 ± 0.63, their acid values, TBA and PV values ranged from 1.42 ± 0.39 to 1.97 ± 0.5;0.11 ± 0.002 to 0.18 ± 0.04;and 2.72 ± 0.14 to 4.43 ± 0.36 respectively, with Brogdon avocado peel variety having the overall best properties prepared blends of trans-free APO margarines showed that increase in APO ratio decreased melting point, increased oxidative stability and reduced moisture content of margarine samples. Chitosan addition leads to decrease moisture content and increase functional properties. VCO lead to increase in phenolic and flavonoid content of the margarines. Samples were spreadable and palatable with R20 being most palatable and the most accepted being R26 with a mean score of 7.07 ± 0.70. Decrease in color intensity increased acceptability. This study therefore demonstrated that avocado peel waste biomass can be valorized by using it as raw material for oil extraction, which can serve as good material for the production of trans-free margarines with good oxidative stability, functional and antioxidant properties. 展开更多
关键词 Food Waste Avocado Peels EXTRACTION OIL Biological Activity MARGARINE CHITOSAN
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Prediction of Low Heating Value of Sugar Cane Bagasse as a Fuel for Industrial Boilers in the High Relative Humidity Region: Case of Cameroon
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作者 Pierre Kana-Donfack Maxell Tientcheu-Nsiewe +1 位作者 Denis Tcheukam-Toko César Kapseu 《Open Journal of Applied Sciences》 2024年第6期1604-1624,共21页
Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised o... Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised on the applicability of these equations in different parts of the globe. This study was initiated to tackle these problems and also check the most suited mathematical models for the Law Heating Value of Cameroonian bagasse. Data and bagasse samples were collected at the Cameroonian sugarcane factory. The effects of cane variety, age of harvesting, source, moisture content, and sucrose on the LHV of Cameroon bagasse have been tested. It was shown that humidity does not change within a variety, but changes from the dry season to the rainy season;the sugar in the rainy season is significantly different from that collected in the dry season. Samples of the same variety have identical LHV. LHV in the dry season is significantly different from LHV in the rainy season. According to the fact that this study was done for cane with different ages of harvesting, the maturity of Cameroonian sugarcane does not affect LHV of bagasse. Tree selected models are much superior tool for the prediction of the LHV for bagasse in Cameroon compared to others. The standard deviation of these validated models is around 200 kJ/kg compared to the experimental. Thus, the models determined in foreign countries, are not necessarily applicable in predicting the LHV of bagasse in other countries with the same accuracy as that in their native country. There was linear relationship between humidity, ash and sugar content in the bagasse. It is possible to build models based on data from physical composition of bagasse using regression analysis. 展开更多
关键词 Sugarcane Bagasse Relative Humidity ASH Low Heating Value
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3D-Printed Boron-Nitrogen Doped Carbon Electrodes for Sustainable Wastewater Treatment via MPECVD
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作者 Iwona Kaczmarzyk Malgorzata Szopińska +7 位作者 Patryk Sokołowski Simona Sabbatini Gabriel Strugala Jacek Ryl Gianni Barucca Per Falas Robert Bogdanowicz Mattia Pierpaoli 《Nano-Micro Letters》 2025年第12期349-368,共20页
This study proposes a novel and sustainable method for fabricating 3D-printed carbon-based electrodes for electrochemical wastewater treatment.We prepared B,N-doped carbon electrodes with hierarchical porosity and a s... This study proposes a novel and sustainable method for fabricating 3D-printed carbon-based electrodes for electrochemical wastewater treatment.We prepared B,N-doped carbon electrodes with hierarchical porosity and a significantly enhanced surface area-to-volume ratio(up to 180%)compared to non-optimized analogues using a synergistic combination of 3D printing,phase inversion,and microwave plasma-enhanced chemical vapor deposition.This process allows the metal-free growth of vertically aligned carbon nanostructures directly onto polymer-derived substrates,resulting in a 20-fold increase in the electrochemically active surface area.Computational fluid dynamics simulations were used to improve mass transport and reduce pressure drop.Electrochemical characterization demonstrated that the optimized electrodes performed significantly better,achieving 4.7-,4-,and 6.5-fold increases in the degradation rates of atenolol,metoprolol,and propranolol,respectively,during electrochemical oxidation.These results highlight the efficacy of the integrated fabrication and simulation approach in producing high-performance electrodes for sustainable wastewater treatment applications. 展开更多
关键词 Carbon nanowall Phase inversion Microwave plasma-enhanced chemical vapor deposition Electrochemical oxidation Additive manufacturing
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Comparison of three methods for natural gas dehydration 被引量:22
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作者 Michal Netusil Pavel Ditl 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第5期471-476,共6页
This paper compares three methods for natural gas dehydration that are widely applied in industry:(1) absorption by triethylene glycol, (2) adsorption on solid desiccants and (3) condensation. A comparison is m... This paper compares three methods for natural gas dehydration that are widely applied in industry:(1) absorption by triethylene glycol, (2) adsorption on solid desiccants and (3) condensation. A comparison is made according to their energy demand and suitability for use. The energy calculations are performed on a model where 105 Nm3/h water saturated natural gas is processed at 30 °C. The pressure of the gas varies from 7 to 20 MPa. The required outlet concentration of water in natural gas is equivalent to the dew point temperature of -10 °C at gas pressure of 4 MPa. 展开更多
关键词 gas reservoir underground gas storage natural gas gas dehydration
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Numerical simulation of gas-liquid two-phase jet flow in air-bubble generator 被引量:4
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作者 陈文义 王静波 +2 位作者 姜楠 赵斌 王振东 《Journal of Central South University》 SCIE EI CAS 2008年第S1期140-144,共5页
Air-bubble generator is the key part of the self-inspiration type swirl flotation machines,whose flow field structure has a great effect on flotation.The multiphase volume of fluid(VOF),standard k-ε turbulent model a... Air-bubble generator is the key part of the self-inspiration type swirl flotation machines,whose flow field structure has a great effect on flotation.The multiphase volume of fluid(VOF),standard k-ε turbulent model and the SIMPLE method were chosen to simulate the present model;the first order upwind difference scheme was utilized to perform a discrete solution for momentum equation.The distributing law of the velocity,pressure,turbulent kinetic energy of every section along the flow direction of air-bubble generator was analyzed.The results indicate that the bubbles are heavily broken up in the middle cross section of throat sect and the entrance of diffuser sect along the flow direction,and the turbulent kinetic energy of diffuser sect is larger than the entrance of throat sect and mixing chamber. 展开更多
关键词 air-bubble GENERATOR NUMERICAL simulation FLOW field BREAKING
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