ABSTRACT
This study introduces the UV/glucose-oxidase@Kaolin (GOD@Kaolin) coupled organic green rust (OGR) system (UV/OGR/GOD@Kaolin) to investigate the promotion of glucose oxidase activity by UV light and its synergistic degradation mechanism for photosensitive pollutants, specifically targeting the efficient degradation of 4-chlorophenol (4-CP). The enzyme system demonstrates its ability to overcome drawbacks associated with traditional Fenton systems, including a narrow pH range and high localized concentration of H2O2, by gradually releasing hydrogen peroxide in situ within a neutral environment. In the presence of UV radiation under specific conditions, enhanced enzyme activity is observed, resulting in increased efficiency in pollutant removal. The gradual release of hydrogen peroxide plays a crucial role in preventing unwanted reactions among active substances. These unique features facilitate the generation of highly reactive species, such as Fe(IV)O, â¢OH, and â¢O2-, tailored to efficiently target the organic components of interest. Additionally, the system establishes a positive iron cycle, ensuring a sustained reactive capability throughout the degradation process. The results highlight the UV/OGR/GOD@Kaolin system as an effective and environmentally friendly approach for the degradation of 4-CP, and the resilience of the enzyme extends the system's applicability to a broader range of scenarios.
Subject(s)
Environmental Pollutants , Water Pollutants, Chemical , Ultraviolet Rays , Hydrogen Peroxide/chemistry , Glucose Oxidase/metabolism , Kaolin , Glucose , Oxidation-Reduction , Water Pollutants, Chemical/chemistryABSTRACT
In order to evaluate the impact of salinity gradients on the aniline biodegradation system, six reactors at salinity concentrations (0%-5%) were established. The results presented the salinity except for 5% imposed negligible effects on aniline degradation performance. Nitrification had prominent resistance to salinity (0%-1.5%) while were significantly restrained when salinity increased. The total nitrogen (TN) removal efficiency of Z4 (1.5%) was 20.5% higher than Z1 (0%) during the stable operation phase. Moreover, high throughput sequencing analysis showed that halophilic bacterium, such as Halomonas, Rhodococcus, remained greater survival advantages in high salinity system. The substantial enrichment of Flavobacterium, Dokdonella, Paracoccus observed in Z4 ensured its excellent nitrogen removal performance. The close cooperation among dominant functional bacteria was strengthened when salt content was below 1.5% while exceeding 1.5% led to the collapse of metabolic capacity through integrating the toxicity of aniline and high osmotic pressure.
Subject(s)
Aniline Compounds , Biodegradation, Environmental , Water Pollutants, Chemical , Aniline Compounds/toxicity , Water Pollutants, Chemical/toxicity , Salt Stress , Bacteria/metabolism , Bacteria/genetics , Bioreactors/microbiology , SalinityABSTRACT
Triggered by the recent experimental synthesis of the Janus PtSSe monolayer, we use the first-principles calculations to predict two new Janus photocatalysts PtXO (X = S, Se), based on the systematic investigations of the structural stabilities, electronic structures, band alignments, catalytic activity and optical absorption. The two Janus structures are found to be mechanically, dynamically and thermodynamically stable, and have suitable band edge positions for the overall water splitting. Owing to the high electron mobility (up to 2164.95 cm2 V-1 s-1) and large disparity between the electron and hole mobilities, together with the indirect band gaps and the intrinsic dipole induced built-in electric fields, the photogenerated electrons/holes can be efficiently separated in PtXO. Moreover, the S/Se vacancy can effectively lower the free energy difference of the HER, making the catalytic reactions occur spontaneously under the potentials of photoexcited electrons and holes. Large optical absorption coefficients (105 cm-1) are also confirmed in the visible light range, and the biaxial tensile strain can further enhance the optical absorption while maintaining the capability of the overall water splitting. Our results not only propose two new Janus materials by demonstrating the possibility of experimental realization, but also indicate that PtXO are peculiar candidates for photocatalytic water splitting.
ABSTRACT
BACKGROUND: Individual susceptibility to valproic acid (VPA)-caused hepatotoxicity might result from genetic deficiencies in the detoxification and antioxidant enzymes including glutathione S-transferases (GSTs), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx). This study aimed to investigate the relationships between GST mu 1 (GSTM1), GST theta 1 (GSTT1), CAT C-262T, GPx1 Pro200Leu, and SOD2 Val16Ala polymorphisms and the risk of abnormal liver function in Chinese epileptic patients treated with VPA monotherapy. METHODS: According to the levels of liver function indicators, a total of 267 epileptic patients between 1 and 65 years of age were divided into normal liver function group and abnormal liver function group. GSTM1 and GSTT1 polymorphisms were determined using polymerase chain reaction (PCR) amplification based on the absence of a PCR amplification product. CAT, GPx1, and SOD2 polymorphisms were identified using PCR-restriction fragment length polymorphism or direct automated DNA sequencing. RESULTS: Carriers of CAT had an increased risk of developing abnormal liver function compared with noncarriers in VPA-treated patients (odds ratio 3.968, P = 0.003). Logistic regression analyses indicated that the CAT genotype was a significant genetic risk factor for VPA-induced liver dysfunction. It suggests that individual susceptibility to VPA-induced liver dysfunction may at least partially result from genetic deficiencies in CAT C-262T.
Subject(s)
Asian People/genetics , Catalase/genetics , Chemical and Drug Induced Liver Injury/genetics , Epilepsy/genetics , Liver/drug effects , Polymorphism, Genetic/genetics , Valproic Acid/adverse effects , Adolescent , Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Child , Epilepsy/drug therapy , Female , Genetic Predisposition to Disease/genetics , Genotype , Humans , Male , Risk Factors , Valproic Acid/therapeutic useABSTRACT
To explore the intrinsic influence of different salinity content on aniline biodegradation system in high temperature condition of 35 ± 1 °C, six groups at various salinity concentration (0.0%-5.0%) were applied. The results showed that the salinity exerted insignificant impact on aniline removal performance. The low-level salinity (0.5%-1.5%) stimulated the nitrogen metabolism performance. The G5-2.5% had excellent adaptability to salinity while the nitrogen removal capacity of G6-5.0% was almost lost. Moreover, high throughput sequencing analysis revealed that the g__norank_f__NS9_marine_group, g__Thauera and g__unclassified_f__Rhodobacteraceae proliferated wildly and established positive correlation each other in low salinity systems. The g__SM1A02 occupying the dominant position in G5 ensured the nitrification performance. In contrast, the Rhodococcus possessing great survival advantage in tremendous osmotic pressure competed with most functional genus, triggering the collapse of nitrogen metabolism capacity in G6. This work provided valuable guidance for the aniline wastewater treatment under salinity stress in high temperature condition.
Subject(s)
Aniline Compounds , Biodegradation, Environmental , Microbiota , Salinity , Salt Stress , Water Pollutants, Chemical , Aniline Compounds/metabolism , Water Pollutants, Chemical/metabolism , Wastewater/chemistry , Nitrogen/metabolism , Hot Temperature , Nitrification , Bacteria/metabolism , Bacteria/geneticsABSTRACT
Integrated fixed-film activated sludge (IFAS) system has considerable advantages in treating aniline wastewater economically and efficiently. However, the response mechanism of IFAS to aniline needs further study. Herein, IFAS in continuous-flow (CF-IFAS) and batch mode (B-IFAS) were set up to investigate it. The removal efficiency of aniline exceeded 99% under different stress intensities. At low stress intensity (aniline ≈ 200 mg/L), the total nitrogen removal efficiency of B-IFAS was approximately 37.76% higher than CF-IFAS. When the stress intensity increased (aniline ≥ 400 mg/L), both were over 82%. CF-IFAS was restrained by denitrification while nitrification in B-IFAS. The legacy effect of perturbation of B-IFAS made microflora quickly reach new stability. The closer interspecific relationship in B-IFAS and more key species: Leucobacter, Rhodococcus, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Ellin6067 and norank_f_NS9_marine_group. Metabolic and Cell growth and death were the most abundant metabolic pathways, resulting both systems the excellent pollutant removal and stability under high stress intensity.
Subject(s)
Bioreactors , Sewage , Wastewater , Nitrification , Nitrogen , Metabolic Networks and Pathways , Denitrification , BiofilmsABSTRACT
In order to examine the impact of Cu(II)-Cr(VI) co-pollution in printing and dyeing wastewater on the aniline biodegradation system (ABS), loading experiments were conducted on ABS at varying concentrations of Cu(II)-Cr(VI). The synergistic stress imposed by Cu(II)-Cr(VI) accelerated the deterioration of the systems, with only the C2-3 (2 mg/L Cr(VI)-3 mg/L Cu(II)) sustaining stable operation for 42 days. However, its nitrogen removal performance remained significantly impaired, resulting in a total nitrogen (TN) removal rate below 40%. High-throughput sequencing analysis revealed a stronger correlation between Cr(VI) and microbial diversity compared to Cu(II). Metagenomic sequencing results demonstrated that Cu(II) emerged as the dominant factor influencing the distribution of dominant bacteria in C2-3, as well as its contribution to contaminant degradation. The complex co-pollution systems hindered aniline degradation and nitrogen metabolism through the combined bio-toxicity of heavy metals and aniline, thereby disrupting the transport chain within the systems matrix.
Subject(s)
Metals, Heavy , Metals, Heavy/metabolism , Chromium/metabolism , Metabolic Networks and Pathways , NitrogenABSTRACT
Developing clean and renewable ocean wave energy is a top priority and an effective way to achieve carbon neutrality. Triboelectric nanogenerators (TENGs) have emerged as promising green and clean energy-harvesting devices. To harvest low-frequency wave energy efficiently, much effort has been made on the modification of the contact surface, which leads to a higher fabrication cost. In this work, we designed a novel "Lucky-Bag" core (LBC) for spherical TENGs with a low-cost and easy fabricating process. The nanofiber/silicone hybrid porous outer layer of the LBC can switch freely from plane to surface and improve the output performance of both the plane and spherical TENGs. Several factors, such as the input frequency, direction, and resistive load, together with the thickness were systematically investigated; the unique porous soft-contact structure increased the triboelectric contact area, and the working mechanism was studied by using the COMSOL software. The experimental results showed that the peak-to-peak open-circuit voltage (Voc) and short-circuit current (Isc) could reach 580 V and 23.5 µA at 1.5 Hz, even under 2D linear motion. Besides, the maximum output power of the spherical TENGs reached 9.10 mW, which can fully power electronic devices such as capacitors and LEDs under water wave triggering. These findings provide useful guidance for optimizing the performance of spherical TENGs for practical applications in harvesting water wave energy.