This study delves into the advanced integration of a ternary heterogeneous Z-scheme photocatalyst, TiO2/CuInS2/OCN (OCN: O-g-C3N4), with carbon quantum dot (CQD) to improve the degradation efficiency ...of reactive yellow 145 (RY145) dye in water. Through a systematic examination, we elucidated the photocatalytic mechanisms and the role of radicals, electrons, and holes in the treatment process. Our findings revealed that this novel catalyst integration significantly boosted RY145 degradation efficiency, achieving 98.2%, which is markedly higher than the efficiencies which could be achieved using TiO2/CuInS2/OCN alone. Moreover, the TiO2/CuInS2/OCN/CQD photocatalyst demonstrated superior rate performance over its components. Comprehensive evaluations, including photoelectrochemical and radical tests, further confirmed the efficiency of the integrated system, adhering to Z-scheme principles. The catalyst showcased remarkable stability, with over 94% reusability after five reaction cycles. These findings pave the way for the potential use of the TiO2/CuInS2/OCN/CQD photocatalyst as an innovative solution for water pollutant treatment via photocatalytic technology.
The objective of this study is to investigate the change in physicochemical properties and digestibility of starches isolated from colored sweet potato varieties under heat-moisture treatment (HMT) ...or annealing treatment (ANN). The results showed that morphology and X-ray diffraction patterns of the sweet potato starches remained unchanged after the HMT or ANN. The HMT significantly reduced peak viscosity, breakdown and setback and significantly increased pasting temperature, trough and final viscosities of the sweet potato starches. The swelling powers and solubility of the heat-moisture treated starches were significantly lower than those of the native or annealed starches. The decreased rapid digestible starch and the increased slowly digestible and resistant starch contents of the sweet potato starches after HMT or ANN as compared to those of the native starches were observed. The resistant starch (RS) contents of the heat-moisture treated sweet potato starches were in a range of 30.6–39.3%, significantly higher than those of the annealed starches (28.8–32.0%). The strong impact of the HMT on physicochemical properties and RS formation of the sweet potato starches compared to the ANN might be due to the high stability of the occurred interactions between starch molecules and amylopectin chains during treatment.
Display omitted
•Ag-g-C3N4@HNTs nanocomposite with uniform Ag-NPs was synthesized by a green synthesis process.•Visible-light photocatalytic activity of TC by Ag-g-C3N4@HNTs nanocomposite was ...significantly improved.•Enhanced photocatalytic activity of nanocomposite can be due to silver surface plasmon resonance of Ag-NPs and multi-layer hollow nanotubes.
In this study, a facile and cost effective green synthesis has been utilized for the synthesis of silver nanoparticles (Ag-NPs)–modified graphitic carbon nitride (Ag-g-C3N4) and halloysite nanotubes (HNTs) using Centella Asiatica (L.) extract, urea and mineral source of natural halloysite (HNTs), respectively. Here, silver ions (Ag+) were reduced to Ag-NPs using an aqueous Centella Asiatica (L.) as reducing and capping agent. The synthesized Ag-g-C3N4@HNTs were characterized by various physiochemical methods such as XRD, FT-IR, BET, SEM, TEM, EDS–mapping, UV–vis-DRS, PL, XPS and EPR methods. In the photocatalytic experiment, Ag-g-C3N4@HNTs nanocomposite with silver surface plasmon resonance of Ag-NPs and multi-layer hollow nanotubes was outperformed by the individual components. With an in-depth study on the photocatalytic mechanisms, we can conclude that the enhanced performance of the nanocomposite is due to the effective separation of photogenerated electrons and superoxide radicals (•O2–) in water molecules. The photocatalyst preserved excellent photostability for up to four cycles (with a minor activity reduction from 95% to 91%). These results demonstrated the development of novel semiconductors from inexpensive resources with effective photoactivity to mitigate environmental problems.
Semiconductor-containing porous materials with a well-defined structure could be unique scaffolds for carrying out selective organic transformations driven by visible light. We herein introduce for ...the first time a heterostructure of silver indium sulfide (AgInS
2
) ternary chalcogenide and a highly porous MIL-101(Cr) metal–organic framework (MOF) synthesised from polyethylene terephthalate plastic waste. Our results demonstrate that AgInS
2
nanoparticles were uniformly attached to each lattice plane of the octahedral MIL-101(Cr) structure, resulting in a nanocomposite with a high distribution of semiconductors in a porous media. We also demonstrate that the nanocomposite with up to 40% of AgInS
2
doping exhibited excellent catalytic activity for tetracycline degradation under visible light irradiation (∼99% tetracycline degraded after 4 h) and predominantly maintained its performance after five cycles. These results could promote a new material circularity pathway to develop new semiconductors that can be used to protect water from further pollution.
A photocatalyst with novel heterostructure (between AgInS2 and MIL-101(Cr)) derived from plastic waste was successfully synthesised for improved tetracycline degradation.
Oxidative-acid-treated nanodiamonds exhibit high affinity for proteins, a property well suited for immobilization of enzymes for biotechnological application. Using lysozyme as an example, this work ...demonstrates that the enzyme can retain much of its activity after physical adsorption to the surfaces of 100-nm diamond crystallites. The activity relative to that of free lysozyme in solution is ∼
60% at the maximum surface coverage of 50% and pH 5. While the enzymatic activity decreases as the surface coverage is lowered, it can be recovered by blocking the empty sites on the surface with supplementary proteins such as cytochrome
c to create a more “crowded” environment. A relative activity up to 70% can be attained at a partial coverage of 20%.
Despite the detrimental effects and life-course health consequences of violence exposure, relatively few studies have adequate capacity to investigate the evolution of violence from childhood to ...motherhood.
This study aims to examine the cyclical nature of childhood abuse and prenatal inter-partner violent victimization (p-IPV) and its adverse impact on childbirth trauma and exclusive breastfeeding (EBF) practice in Vietnam.
Using a prospective birth cohort, 150 pregnant women were recruited in the third trimester of pregnancy in Hue city in central Vietnam (Wave 1-Baseline) and re-interviewed approximately three months after delivery (Wave 2-Follow-up). The direct and indirect effects of violent victimization on subsequent childbirth experience (measured by Birth Memories and Recall Questionnaire) and EBF practice were estimated by using augmented-inverse-probability-weighted models, sensitivity analysis, and structural equation model.
Detrimental and prolonged effects of the inter-generational cycle of violence transverse childhood to motherhood. Women who experienced either childhood abuse or p-IPV violence were more likely to experience negative emotional childbirth memories ARR 1.21, 95 % CI (1.04, 1.39). Evidence also suggested that not continuing to exclusively breastfeed at 3 months post-partum was strongly associated with prenatal depression, young age, and perceived low social status during pregnancy. Perceived strong connectedness among extended family members and social networks (i.e. nexus among family, friends, and neighborhood) provided a buffering effect by preventing EBF termination.
This research provides insights into the protective role of social connectedness in improving breastfeeding practice. It is vital to establish wholistic antenatal care and social service system to offer specialized support and response for victims of violence and mitigate the long-term sequelae of traumatic events.
•Mothers with violence victimization during childhood and during pregnancy have a higher risk of adverse childbearing experiences.•Women experienced childhood abuse are more likely to suffer the harmful long-term effects on prenatal depression and being re-victimized.•Prenatal depression and perceived low social status during pregnancy may predict cessation of exclusive breastfeeding postnatally.•Having a strong intergenerational connectedness during pregnancy may have a buffering effect by maintaining exclusive breastfeeding.
This study delves into the advanced integration of a ternary heterogeneous Z-scheme photocatalyst, TiO
/CuInS
/OCN (OCN: O-g-C
N
), with carbon quantum dot (CQD) to improve the degradation efficiency ...of reactive yellow 145 (RY145) dye in water. Through a systematic examination, we elucidated the photocatalytic mechanisms and the role of radicals, electrons, and holes in the treatment process. Our findings revealed that this novel catalyst integration significantly boosted RY145 degradation efficiency, achieving 98.2%, which is markedly higher than the efficiencies which could be achieved using TiO
/CuInS
/OCN alone. Moreover, the TiO
/CuInS
/OCN/CQD photocatalyst demonstrated superior rate performance over its components. Comprehensive evaluations, including photoelectrochemical and radical tests, further confirmed the efficiency of the integrated system, adhering to Z-scheme principles. The catalyst showcased remarkable stability, with over 94% reusability after five reaction cycles. These findings pave the way for the potential use of the TiO
/CuInS
/OCN/CQD photocatalyst as an innovative solution for water pollutant treatment
photocatalytic technology.
Abstract
Strong nonlocal thermodynamic equilibrium recombination line emission from the envelope of MWC 349A has been studied observationally and theoretically and has been used to derive information ...about the physical and kinematic properties of the circumstellar environment around this object. In this paper, we construct a detailed model of radiative transfer of the commonly observed maser lines H26
α
and H30
α
in MWC 349A, specifically taking into account the effect of maser saturation. The envelope is modeled as a combination of an ionized Keplerian rotating disk and a disk wind expanding at a velocity of 60 km s
−1
. Our modeling results show that millimeter-line H26
α
is significantly affected by the saturation effect. The line intensity is predicted to be greatly reduced in comparison with previous models which ignore the saturation effect. The H30
α
maser is predicted to be unsaturated. Our model shows that the predicted intensity and line shape are in agreement with observations. The predicted position–velocity diagrams are also consistent with observations and the interpretation that the H26
α
maser appears at smaller radii in comparison to the H30
α
maser. We also emphasize that the wind component is important in shaping the line profiles of the recombination masers.
We have studied the defect states and electronic transport mechanisms in the mismatched p-InP/i-InGaAs/n-InP photodiode grown by molecular beam epitaxy (MBE) using deep-level transient spectroscopy ...(DLTS) and current–voltage (I–V) measurements. Two defect states were observed in the p-InP layer, which could have originated from Zn diffusion, and another one detected in i-InGaAs acted as a dislocation defect. The total defect density of the device estimated by DLTS and space-charge limited current (SCLC) was about 4 × 1013, which was much lower than the device grown by other methods. I–V measurements pointed out that the leakage current in this photodiode was caused by the existence of defect states and the small conduction band offset. Therefore, to suppress the leakage current in the devices, it is urgent to reduce the trap density and optimize the thickness of the p-InP layer. The study of defect state and electronic transport mechanism in p-InP/i-InGaAs/n-InP PIN diodes could help to develop a strategy to improve the SWIR sensing technology in the future.
PDF
