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Ultrasonically synthesized core-shell Au/Pt nanoparticles decorated g-C3N4heterostructures for enhanced sunlight-driven photocatalytic degradation of aflatoxin B1 in domestic wastewater
(2025-10-01)
Mathaweesansurn, Arjnarong
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Peensuwan, Natthakan
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Paiboonbudsrakum, Tanyapat
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Chiangthap, Tanawan
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Chinnawat, Sirinyakorn
The discharge of domestic wastewater from washing agricultural products contaminated with aflatoxin B1 (AFB1), even at low concentrations, poses significant risks to food chain integrity and public health. Core-shell Au/Pt nanoparticles anchored on a g-C3N4 heterostructure (Au-PtNPs/g-C3N4) were developed as a highly promising photocatalyst for the efficient degradation of AFB1 in domestic wastewater treatment applications. Herein, core-shell Au-PtNPs were synthesized via a straightforward one-step chemical reduction method assisted by ultrasonic irradiation. The core-shell Au-PtNPs (46.52±0.15nm) were uniformly anchored onto the g-C3N4 nanosheets via hydrogen bonding during ultrasonic dispersion. The Au-PtNPs/g-C3N4 composites were systematically characterized and evaluated for AFB1 photodegradation. Complete removal of AFB1 (50μgL-1) was accomplished within just 1min under natural sunlight using 0.50mg of catalyst at pH 7.0, demonstrating a 6.7-fold enhancement over pristine g-C3N4. Mechanistic investigations confirmed that the AuNPs core induced a surface plasmon resonance (SPR) effect that broadened visible-light absorption, while the PtNPs shell served as an efficient electron sink, facilitating charge separation. Simultaneously, the g-C3N4 nanosheets functioned as a visible-light-responsive photoactive scaffold, promoting effective charge generation and directional migration across the heterojunction interface. These synergistic effects were validated by diffuse reflectance UV-vis spectroscopy, linear sweep voltammetry, electrochemical impedance spectroscopy, photoluminescence quenching, and Mott-Schottky analysis. The combined enhancements significantly promoted the generation of reactive oxygen species (•O-2, •OH and h∗), driving the efficient photodegradation of AFB1. Thus, the Au-PtNPs/g-C3N4 photocatalyst provides a promising, sunlight-driven strategy for AFB1 detoxification in real wastewater from domestic, agricultural and food industry sources.
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Dataset of air cargo supply chain conditions and fruit quality evolution: Case study of mango shipment from Thailand to France
(2025-08-01)
Paviet-Salomon, Y.
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Laguerre, O.
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Duret, S.
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Denis, A.
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Mawilai, P.
This study presents a detailed dataset collected during the international transport of mangoes (Mangifera indica L. cv. ‘Nam Dok Mai Si-Thong’) within a fully loaded Unit Load Device (ULD). The ULD contained 148 boxes (14 mangoes/box) and 31 boxes were instrumented by data loggers to monitor air and mango temperatures, as well as air humidity along the shipment. Measurements were recorded every 5 min throughout the 86.2 hour journey from Bangkok (Thailand) to Paris (France), it included cold storage, refrigerated transport, airport warehouse, air transport, and final delivery to the FRISE-INRAE laboratory in Paris suburban. At reception (Day 3), all boxes were stored at two temperatures (16 °C and 21 °C) over 15 days during which mango quality was assessed. Key quality attributes such as mass loss, peel color, pH, sugar content, and visual appearance were evaluated at Day 3, Day 6, Day 9, and Day 15 to highlight the impact of storage conditions on fruit quality. It is to be noticed that the same quality assessment was undertaken after harvest and before the cold storage in Thailand (Day 0). The dataset comprises raw and processed data files that include the temperature and humidity changes over time, as well as the quality evolution. These data are stored in series of txt files, with raw values and processed results i.e. min, max, average values, standard deviation and variance to facilitate future analysis. Additionally, the dataset includes series of jpeg files of mango images at different assessment days. This dataset is valuable for both practical and research purposes. For fruit exporters, it offers the insights into how different positions within a ULD can affect mango quality during a long-distance transport and implements certain measures to minimize quality degradation. For researchers, the dataset provides a base for numerical models validation, such as simplified thermal models and Computational Fluid Dynamics simulations. The international supply chain dataset is rare because of the complexity and the cost of implementation.
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Hydrolytic degradation of poly(lactic acid): Population balance modelling for simulating molecular weight distribution
(2025-04-01)
Limsukon, Wanwarang
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Rubino, Maria
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Rabnawaz, Muhammad
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Lim, Loong Tak
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Sakkaplangkul, Puttha
Poly (lactic acid) (PLA) is one of the most promising biobased and biodegradable polymers able to replace several fossil-based plastics for packaging and other applications. However, PLA is susceptible to hydrolytic degradation, impacting its overall service performance and end-of-life. The molecular weight distribution (MWD) is a critical parameter that provides insights during hydrolytic degradation. In this study, we introduced a population balance model, utilizing the high-order moment-conserving method of classes, to describe the MWD during the hydrolytic degradation of amorphous PLA film at 45 °C and 65 °C and expanded to 85 °C. The phenomenological model provided hydrolysis constants that clarified noncatalytic and autocatalytic reaction mechanisms and information on specific chain scission of a particular length. Our predictions demonstrate a promising alignment in weight location and distribution shape with the experimental MWDs observed throughout the hydrolytic process of PLA. One notable advantage is the MWD simulation, conducted over an extended time frame. Furthermore, this predictive capability extends to forecasting the lifetime of PLA films at various temperatures within the tested range, thereby fostering insights into PLA hydrolysis applicable to real-life scenarios and supporting environmentally conscious degradation practices.
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Electrospinning of Nanofibers Effect of Gelatin by Polycaprolactone and Carboxymethyl Cellulose Degradation Characteristics
(2025-01-01)
Meesa, Banpot
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Klongboonjit, Sakon
This study aims to investigate the degradation of gelatin-based polycaprolactone and carboxymethyl cellulose scaffolds produced through the electrospinning technique for nanofiber scaffolds. The experimental design varies the voltage and feed rate for different ratios of gelatin, polycaprolactone, cellulose, and carboxymethyl cellulose, which are 100/0/0, 90/5/5, 80/15/5, 70/25/5, and 60/35/5, respectively. An organic solvent, 2,2,2-trifluoroethanol, which is a suitable solvent for gelatin, polycaprolactone, and carboxymethyl cellulose, is used, though the materials are dissolved in water to prepare the raw material for electrospinning. To characterize the scaffolds, their physical properties are analyzed, including fiber morphology and size, using scanning electron microscopy. The results reveal that as the polycaprolactone content increases from 0%, 5%, 15%, 25%, to 35%, with carboxymethyl cellulose maintained at 0% or 5%, the fiber size decreases from 1.5 μm to 5.2 μm. This suggests that electrospinning is effective for fabricating scaffolds from all three materials. Furthermore, the decomposition rates are optimized for GPC90/5/5, GPC80/15/5, and GPC70/25/5, which completely decompose within 36 hours. Additionally, GPC80/15/5 shows a good degradation rate, while GPC100/0/0 and GPC60/35/5 exhibit rapid degradation.
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Exploration of an efficient method for removing antibiotics from water and digested sewage sludge using Fe(VI): Kinetics and P phytoavailability and compostability in treated sludge
(2023-09-01)
Limmun, Warunee
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Ishikawa, Nao
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Maeda, Takeki
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Umeda, Takayuki
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Song, Jie
Potassium ferrate (K<inf>2</inf>FeO<inf>4</inf>) containing hexavalent iron [Fe(VI)] is an environmentally friendly oxidant, which possesses strong oxidizing power to treat wastewater and sludge. Therefore, the present study investigated degradation of selected antibiotics, namely levofloxacin (LEV), ciprofloxacin (CIP), oxytetracycline (OTC), and azithromycin (AZI), in water and anaerobically digested sewage sludge samples using Fe(VI). The effects of different Fe(VI) concentrations and initial pH values on antibiotic removal efficiency were evaluated. Under the studied conditions, LEV and CIP were almost completely removed from water samples, following second-order kinetics. In addition, over 60% of the four selected antibiotics were removed from sludge samples using 1 g L−1 Fe(VI). Furthermore, P phytoavailability and compostability of Fe(VI)-treated sludge were evaluated using different extraction reagents and a small composting unit. The extraction efficiency of phytoavailable P using 2% citric acid and neutral ammonium citrate was approximately 40% and 70%, respectively. The mixture of Fe(VI)-treated sludge and rice husk was self-heated in a closed composting reactor through the biodegradation of organic matter derived from the treated sludge. Therefore, Fe(VI)-treated sludge may be used as an organic material containing phytoavailable P for compost.
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A novel catalyst from water treatment sludge for catalytic ozonation to degrade phenol
(2019-05-01)
Sukmilin, Apiradee
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Boonchom, Banjong
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Jarusutthirak, Chalor
Water treatment sludge (WTS) from a water treatment plant has been successfully converted into a novel catalyst. Catalytic ozonation using the WTS as a catalyst for degradation of phenol was studied. Water treatment sludge was dried naturally for 7 days, then grounded and sieved through a standard mesh with a size no. of 100, equivalent to less than 150 micron in size. The WTS was characterized by X-ray fluorescence spectrometer (XRF) and X-ray diffractometer (XRD). The XRF analysis showed that water treatment sludge contained silica of 49.90%, Al<inf>2</inf>O<inf>3</inf> of 24.40 %, and Fe<inf>2</inf>O<inf>3</inf> of 10.40 %. The XRD analysis illustrated that the structure of water treatment sludge was similar to that of kaolin clay. Factors affecting phenol removal efficiency including reaction time (0, 5, 10, 15, 30, 60, 90 and 120 min), pH (3, 7, and 11) and catalyst dosage (1, 3 and 5 g/L) were investigated. At the optimum conditions, i.e. reaction time of 120 min, pH of 11, and catalyst dosage of 3 g/L, the removal efficiency of phenol was 59.16% which was higher than that of sole ozonation (44.61%). According to kinetic analysis, it was found that the experimental data fit well with pseudo-first order kinetic model with a rate constant (K<inf>obs</inf>) of 0.0347 min-1 while that of sole ozone was 0.0162 min-1.
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Autolysis of clown featherback (Chitala ornata) muscle
(2019-01-01)
Thiabmak, Chompunutch
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Sriket, Chodsana
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Yarnpakdee, Suthasinee
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Kim, Siriporn Riebroy
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Nalinanon, Sitthipong
Clown featherback (Chitala ornata) is a freshwater fish important in the cuisine of Thailand and other Southeast Asian countries. It has a short marketable life due mainly to poor gelling characteristic even when stored in ice. This deterioration has been associated with muscle autolysis. The research was aimed to investigate the autolysis of clown featherback muscle (CFM). To test autolysis, mince from CFM was incubated in a temperature controlled water bath for 60 min at 5, 10, 20, 30, 40, 50, 60, 65, 70, 75 or 80 °C at pH levels over the range of 2-11. The results showed that the highest autolytic activity was at 70 °C and it occurred at pH levels of 4 and 7, with pH 4 showing the highest autolysis. CFM was incubated with its crude enzyme counterpart at the physiological pH (6.73) at both 4 °C and 25 °C. Degradation of natural actomyosin showed that after incubation at either temperature myosin heavy chain was susceptible to hydrolysis indicating that autolysis of CFM took place even at low temperature as affected by its endogenous proteases. The effects of several protease inhibitors were tested and autolysis at the physiological pH (6.73) was strongly inhibited by 10 μM pepstatin A (20.3% inhibition), which had significantly higher inhibitory activity (P < 0.05) among the protease inhibitors tested. This suggests that aspartic protease was the major proteinase in CFM.
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Degradation of polyethylene terephthalate bottles after long sunlight exposure
(2019-01-01)
Chaisupakitsin, Malinee
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Chairat-Utai, Pitsamai
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Jarusiripot, Chutima
Effects of sunlight on PET bottles degradation and liquid filled inside the bottles were studied. Three types of soft drinks filled in Polyethylene terephthalate (PET) bottles; drinking water in clear bottle, carbonated water in green, and pink bottles was left on the rooftop of building for 8 months. After long exposure to sunlight, the bottles’ shapes were not changed, but the tensile strength of plastics decreased. Moreover, the enthalpy of fusion which corresponds to molecular rearrangement of plastics increased. The results from FTIR showed slightly increased of peak hydroxyl group at 3,400 cm-1 on outer surface of PET bottle. Sunlight slowly degraded the chemical structure on outer surface of PET bottle by photo-hydrolysis reaction. The pH of water for all samples changed from acid to base. By using Tollen’s reagent, aldehyde was found clearly in drinking water after sunlight exposure, but was not observed in green and pink water.
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Effect of concentrated natural rubber latex on the properties and degradation behavior of cotton-fiber-reinforced cassava starch biofoam
(2017-12-01)
Sanhawong, Wanchinee
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Banhalee, Pakamas
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Boonsang, Siridech
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Kaewpirom, Supranee
Eco-friendly starch biofoams derived from natural rubber were fabricated in this study. To overcome their two main shortcomings, i.e., lack of flexibility and susceptibility to moisture, cotton fiber and concentrated natural rubber latex (CNRL) were incorporated into the biofoam products. Cotton-fiber-reinforced cassava starch biofoams were successfully prepared by compression molding using water as the solvent, a processing aid, and a blowing agent. The morphology and the physical, flexural, and thermal properties of the starch biofoams as a function of the CNRL content were investigated. The moisture adsorption capacity of the foam decreased with increasing CNRL content up to 5 phr (−73.4% and −41.78% at 0 and 100% RH, respectively). With increasing CNRL content, the hydrophobicity of the biofoam increased, as evidenced by contact angle measurements; this result suggested better moisture resistance and dimensional stability. The flexural properties of the biofoams were tuned by adjusting the CNRL content. With the addition of the CNRL content of 2.5 phr, the elongation of the biofoam clearly improved by 24%, with an acceptable decrease (−2.2%) in the bending modulus. Biodegradation by the soil burial test revealed that the degradation of the biofoam mainly proceeds by hydrolysis, and the addition of CNRL retards the degradation of the biofoam.
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Fabrication of Anodic Titanium Oxide (ATO) for waste water treatment application
(2017-01-01)
Choksumlitpol, Pimsuree
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Mangkornkarn, Chayangkoon
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Sumtong, Peerawith
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Onlaor, Korakot
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Eiad-Ua, Apiluck
In this study, forming of Anodic Titanium Oxide (ATO) that has a nanoporous and nanotube morphology was studied for waste water treatment application. Nanoporous anodic titanium oxide was obtained by anodization, using ethylene glycol merging with ammonium fluoride at room temp as electrolyte. The variables of the process were anodization time (5, 10, 15 and 20 min) and anodization voltages (20, 40 and 60 V). Field emission scanning electron microscopy revealed that separated nanotubes became obvious when the voltage is high. The samples with different ATO conditions were investigated by the degradation of methylene blue under UV light irradiation. It was found that the activity of the photocatalysis of ATO was significantly enhancement of the degradation of methylene blue. These results suggest that ATO/UV photocatalysis as a method for treatment of diluted waste waters in textile industries.

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