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1.
Angew Chem Int Ed Engl ; : e202402882, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594208

RESUMO

Circularly polarized luminescence (CPL)-active molecular materials have drawn increasing attention due to their promising applications for next-generation display and optoelectronic technologies. Currently, it is challenging to obtain CPL materials with both large luminescence dissymmetry factor (glum) and high quantum yield (Φ). A pair of enantiomeric N^N^C-type Pt(II) complexes (L/D)-1 modified with chiral Leucine methyl ester are presented herein. Though the solutions of these complexes are CPL-inactive, the spin-coated thin films of (L/D)-1 exhibit giantly-amplified circularly polarized phosphorescences with |glum| of 0.53 at 560 nm and Φair of ~50%, as well as appealing circular dichroism (CD) signals with the maximum absorption dissymmetry factor |gabs| of 0.37-0.43 at 480 nm. This superior CPL performance benefits from the hierarchical formation of crystalline fibrillar networks upon spin coating. Comparative studies of another pair of chiral Pt(II) complexes (L/D)-2 with a symmetric N^C^N coordination mode suggest that the asymmetric N^N^C coordination of (L/D)-1 are favorable for the efficient exciton delocalization to amplify the CPL performance. Optical applications of the thin films of (L/D)-1 in CPL-contrast imaging and inducing CP light generation from achiral emitters and common light-emitting diode lamps have been successfully realized.

2.
J Mol Cell Biol ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587834

RESUMO

Glutamate dehydrogenase 1 (GLUD1) is implicated in oncogenesis. However, little is known about the relationship between GLUD1 and hepatocellular carcinoma (HCC). In the present study, we demonstrated that the expression levels of GLUD1 significantly decreased in tumors, which was relevant to the poor prognosis of HCC. Functionally, GLUD1 silencing enhanced the growth and migration of HCC cells. Mechanistically, the upregulation of interleukin-32 through AKT activation contributes to GLUD1 silencing-facilitated hepatocarcinogenesis. The interaction between GLUD1 and AKT, as well as α-ketoglutarate regulated by GLUD1, can suppress AKT activation. In addition, LIM and SH3 protein 1 (LASP1) interacts with GLUD1 and induces GLUD1 degradation via the ubiquitin-proteasome pathway, which relies on the E3 ubiquitin ligase synoviolin (SYVN1), whose interaction with GLUD1 is enhanced by LASP1. In hepatitis B virus (HBV)-related HCC, the HBV X protein (HBX) can suppress GLUD1 with the participation of LASP1 and SYVN1. Collectively, our data suggest that GLUD1 silencing is significantly associated with HCC development, and LASP1 and SYVN1 mediate the inhibition of GLUD1 in HCC, especially in HBV-related tumors.

3.
J Colloid Interface Sci ; 665: 1065-1078, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38579389

RESUMO

Reactive oxygen species (ROS)-centered chemodynamic therapy (CDT) holds significant potential for tumor-specific treatment. However, insufficient endogenous H2O2 and extra glutathione within tumor microenvironment (TME) severely deteriorate the CDT's effectiveness. Herein, rich-Zn-Co3O4/N-doped porous carbon (Zn-Co3O4/NC) was fabricated by two-step pyrolysis, and applied to build high-efficiency nano-platform for synergistic cancer therapy upon combination with glucose oxidase (GOx), labeled Zn-Co3O4/NC-GOx for clarity. Specifically, the multiple enzyme-like activities of the Zn-Co3O4/NC were scrutinously investigated, including peroxidase-like activity to convert H2O2 to O2∙-, catalase-like activity to decompose H2O2 into O2, and oxidase-like activity to transform O2 to O2∙-, which achieved the CDT through the catalytic cascade reaction. Simultaneously, GOx reacted with intracellular glucose to produce gluconic acid and H2O2, realizing starvation therapy. In the acidic TME, the Zn-Co3O4/NC-GOx rapidly caused intracellular Zn2+ pool overload and disrupted cellular homeostasis for ion-intervention therapy. Additionally, the Zn-Co3O4/NC exhibited glutathione peroxidase-like activity, which consumed glutathione in tumor cells and reduced the ROS consumption for ferroptosis. The tumor treatments offer some constructive insights into the nanozyme-mediated catalytic medicine, coupled by avoiding the TME limitations.


Assuntos
Cobalto , Peróxido de Hidrogênio , Neoplasias , Óxidos , Humanos , Porosidade , Espécies Reativas de Oxigênio , Glucose Oxidase , Imidazóis , Carbono , Glutationa , Zinco , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral
4.
Nanoscale ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572999

RESUMO

As thin films of semiconducting covalent organic frameworks (COFs) are demonstrating utility for ambipolar electronics, channel materials in organic electrochemical transistors (OECTs), and broadband photodetectors, control and modulation of their thin film properties is paramount. In this work, an interfacial growth technique is utilized to synthesize imine TAPB-PDA COF films at both the liquid-liquid interface as well as at the liquid-solid interface on a Si/SiO2 substrate. The concentration of acetic acid catalyst in the aqueous phase is shown to significantly influence the thin film morphology of the liquid-solid growth, with concentrations below 1 M resulting in no film nucleation, concentrations of 1-4 M enabling smooth film formation, and concentrations greater than 4 M resulting in films with a higher density of particulates on the surface. Importantly, while the films grown at the liquid-liquid interface are mixed-orientation, those grown directly at the liquid-solid interface on the Si/SiO2 surface have highly oriented COF layers aligned parallel to the substrate surface. Moreover, this liquid-solid growth process affords TAPB-PDA COF thin films with p-type charge transport having a transconductance of 10 µS at a gate voltage of -0.9 V in an OECT device structure.

5.
Mol Phylogenet Evol ; 196: 108072, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615706

RESUMO

While the diversity of species formation is broadly acknowledged, significant debate exists regarding the universal nature of hybrid species formation. Through an 18-year comprehensive study of all Populus species on the Qinghai-Tibet Plateau, 23 previously recorded species and 8 new species were identified. Based on morphological characteristics, these can be classified into three groups: species in section Leucoides, species with large leaves, and species with small leaves in section Tacamahaca. By conducting whole-genome re-sequencing of 150 genotypes from these 31 species, 2.28 million single nucleotide polymorphisms (SNPs) were identified. Phylogenetic analysis utilizing these SNPs not only revealed a highly intricate evolutionary network within the large-leaf species of section Tacamahaca but also confirmed that a new species, P. curviserrata, naturally hybridized with P. cathayana, P. szechuanica, and P. ciliata, resulting in 11 hybrid species. These findings indicate the widespread occurrence of hybrid species formation within this genus, with hybridization serving as a key evolutionary mechanism for Populus on the plateau. A novel hypothesis, "Hybrid Species Exterminating Their Ancestral Species (HSEAS)," is introduced to explain the mechanisms of hybrid species formation at three different scales: the entire plateau, the southeastern mountain region, and individual river valleys.

6.
Phys Chem Chem Phys ; 26(16): 12564-12572, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38595124

RESUMO

The ß-Ga2O3 crystal is a significant ultrawide bandgap semiconductor with great potential in ultraviolet optoelectronics and high-power devices. Planar defects in ß-Ga2O3 have been observed in experiments, but their structures, influences, formation mechanism, and controlling methods remain to be studied. We conducted a comprehensive study of ß-Ga2O3 planar defects using density functional theory. We determined the atomic structures of planar defects (stacking faults and twins) on (100), (001), and (-201) planes in ß-Ga2O3 crystals and calculated the formation energy and band structure of each defect. Our results indicate that the formation energy of stacking faults on the (100) plane and twins on the (100) and (-201) planes was extremely low, which explained why these planar defects were observed readily. We also studied the influence of common impurities (Si, Sn, Al, H) and vacancies in ß-Ga2O3 crystals on the formation of these planar defects. Our findings revealed that specific impurities and vacancies could facilitate the formation of planar defects or even make them spontaneous. This research provides critical insights into the atomic structures of planar defects in ß-Ga2O3, and explains why they form readily from the perspective of formation energy. These insights are important for future research into ß-Ga2O3 defects.

7.
Mar Pollut Bull ; 202: 116361, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38636345

RESUMO

A variety of machine learning (ML) models have been extensively utilized in predicting biomass pyrolysis owing to their prowess in deciphering complex non-linear relationships between inputs and outputs, but there is still a lack of consensus on the optimal methods. This study elaborates on the development, optimization, and evaluation of three ML methodologies, namely, artificial neural networks, random forest (RF), and support vector machines, aimed to determine the optimal model for accurate prediction of biomass pyrolysis behavior using thermogravimetric data. This work assesses the utility of thermal data derived from these models in the computation of kinetic and thermodynamic parameters, alongside an analysis of their statistical performance. Eventually, the RF model exhibits superior physical interpretability and the least discrepancy in predicting kinetic and thermodynamic parameters. Furthermore, a feature importance analysis conducted within the RF model framework quantitatively reveals that temperature and heating rate account for 98.5 % and 1.5 %, respectively.

8.
Cell Commun Signal ; 22(1): 234, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643181

RESUMO

BACKGROUND: p66Shc, as a redox enzyme, regulates reactive oxygen species (ROS) production in mitochondria and autophagy. However, the mechanisms by which p66Shc affects autophagosome formation are not fully understood. METHODS: p66Shc expression and its location in the trophoblast cells were detected in vivo and in vitro. Small hairpin RNAs or CRISPR/Cas9, RNA sequencing, and confocal laser scanning microscope were used to clarify p66Shc's role in regulating autophagic flux and STING activation. In addition, p66Shc affects mitochondrial-associated endoplasmic reticulum membranes (MAMs) formation were observed by transmission electron microscopy (TEM). Mitochondrial function was evaluated by detected cytoplastic mitochondrial DNA (mtDNA) and mitochondrial membrane potential (MMP). RESULTS: High glucose induces the expression and mitochondrial translocation of p66Shc, which promotes MAMs formation and stimulates PINK1-PRKN-mediated mitophagy. Moreover, mitochondrial localized p66Shc reduces MMP and triggers cytosolic mtDNA release, thus activates cGAS/STING signaling and ultimately leads to enhanced autophagy and cellular senescence. Specially, we found p66Shc is required for the interaction between STING and LC3II, as well as between STING and ATG5, thereby regulates cGAS/STING-mediated autophagy. We also identified hundreds of genes associated several biological processes including aging are co-regulated by p66Shc and ATG5, deletion either of which results in diminished cellular senescence. CONCLUSION: p66Shc is not only implicated in the initiation of autophagy by promoting MAMs formation, but also helps stabilizing active autophagic flux by activating cGAS/STING pathway in trophoblast.


Assuntos
Autofagossomos , 60683 , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Autofagossomos/metabolismo , Autofagia , DNA Mitocondrial/metabolismo , Trofoblastos/metabolismo , Glucose/metabolismo , Nucleotidiltransferases/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-38628818

RESUMO

Purpose: Results from studies of extended capecitabine after the standard adjuvant chemotherapy in early stage triple-negative breast cancer (TNBC) were inconsistent, and only low-dose capecitabine from the SYSUCC-001 trial improved disease-free survival (DFS). Adjustment of the conventional adjuvant chemotherapy doses affect the prognosis and may affect the efficacy of subsequent treatments. This study investigated whether the survival benefit of the SYSUCC-001 trial was affected by dose adjustment of the standard adjuvant chemotherapy or not. Patients and Methods: We reviewed the adjuvant chemotherapy regimens before the extended capecitabine in the SYSUCC-001 trial. Patients were classified into "consistent" (standard acceptable dose) and "inconsistent" (doses lower than acceptable dose) dose based on the minimum acceptable dose range in the landmark clinical trials. Cox proportional hazards model was used to investigate the impact of dose on the survival outcomes. Results: All 434 patients in SYSUCC-001 trial were enrolled in this study. Most of patients administered the anthracycline-taxane regimen accounted for 88.94%. Among patients in the "inconsistent" dose, 60.8% and 47% received lower doses of anthracycline and taxane separately. In the observation group, the "inconsistent" dose of anthracycline and taxane did not affect DFS compared with the "consistent" dose. Moreover, in the capecitabine group, the "inconsistent" anthracycline dose did not affect DFS compared with the "consistent" dose. However, patients with "consistent" taxane doses benefited significantly from extended capecitabine (P=0.014). The sufficient dose of adjuvant taxane had a positive effect of extended capecitabine (hazard ratio [HR] 2.04; 95% confidence interval [CI] 1.02 to 4.06). Conclusion: This study found the dose reduction of adjuvant taxane might negatively impact the efficacy of capecitabine. Therefore, the reduction of anthracycline dose over paclitaxel should be given priority during conventional adjuvant chemotherapy, if patients need dose reduction and plan for extended capecitabine.

10.
World J Gastroenterol ; 30(11): 1497-1523, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38617454

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a malignant epithelial tumor, characterized by squamous cell differentiation, it is the sixth leading cause of cancer-related deaths globally. The increased mortality rate of ESCC patients is predominantly due to the advanced stage of the disease when discovered, coupled with higher risk of metastasis, which is an exceedingly malignant characteristic of cancer, frequently leading to a high mortality rate. Unfortunately, there is currently no specific and effective marker to predict and treat metastasis in ESCC. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules, approximately 22 nucleotides in length. miRNAs are vital in modulating gene expression and serve pivotal regulatory roles in the occurrence, progression, and prognosis of cancer. Here, we have examined the literature to highlight the intimate correlations between miRNAs and ESCC metastasis, and show that ESCC metastasis is predominantly regulated or regulated by genetic and epigenetic factors. This review proposes a potential role for miRNAs as diagnostic and therapeutic biomarkers for metastasis in ESCC metastasis, with the ultimate aim of reducing the mortality rate among patients with ESCC.


Assuntos
Carcinoma , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Humanos , MicroRNAs/genética , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/genética , Epigenômica
11.
J Phys Chem Lett ; : 4721-4728, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660969

RESUMO

Knowing heat capacity is crucial for modeling temperature changes with the absorption and release of heat and for calculating the thermal energy storage capacity of oxide mixtures with energy applications. The current prediction methods (ab initio simulations, computational thermodynamics, and the Neumann-Kopp rule) are computationally expensive, not fully generalizable, or inaccurate. Machine learning has the potential of being fast, accurate, and generalizable, but it has been scarcely used to predict mixture properties, particularly for mixed oxides. Here, we demonstrate a method for the generalizable prediction of heat capacity of solid oxide pseudobinary mixtures using heat capacity data obtained from computational thermodynamics and descriptors from ab initio databases. Models trained through this workflow achieved an error (mean absolute error of 0.43 J mol-1 K-1) lower than the uncertainty in differential scanning calorimetry measurements, and the workflow can be extended to predict other properties derived from the Gibbs free energy and for higher-order oxide mixtures.

12.
BMC Psychol ; 12(1): 216, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637843

RESUMO

BACKGROUND: Problematic Internet Use (PIU), characterized by failures to control the overuse of internet, is associated with a range of functional impairments. However, there is limited research on the specific impact of PIU on inhibitory control functions, particularly in terms of differentiating between prepotent response inhibition and interference control. Therefore, the main objective of this study is to investigate these two components of inhibitory control in individuals with PIU. METHODS: Thirty participants who met the PIU criteria and 30 control participants were included in the present study. All participants completed the Go/No-Go and Flanker tasks, in which internet-related images and words were used as task stimuli. RESULTS: In the Go/No-Go task, all participants exhibited poorer performance in inhibiting internet-related stimuli compared to internet-unrelated stimuli, during the No-Go trials. In the Flanker task, results revealed a three-way interaction of Group, Stimulus type and Congruency. Specifically, in the incongruent condition, participants with PIU exhibited slower responses for internet-unrelated targets compared to internet-related targets, whereas no similar effect was observed among individuals with low internet use. CONCLUSIONS: The findings suggest that difficulties in controlling the interference effect of internet-related information represent a key dysfunction in inhibitory control of PIU.


Assuntos
Comportamento Aditivo , Humanos , Uso da Internet , Inibição Psicológica , Internet
13.
Nat Commun ; 15(1): 2552, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38514649

RESUMO

Sulfide electrolytes represent a crucial category of superionic conductors for all-solid-state lithium metal batteries. Among sulfide electrolytes, glassy sulfide is highly promising due to its long-range disorder and grain-boundary-free nature. However, the lack of comprehension regarding glass formation chemistry has hindered their progress. Herein, we propose interstitial volume as the decisive factor influencing halogen dopant solubility within a glass matrix. We engineer a Li3PS4-Li4SiS4 complex structure within the sulfide glassy network to facilitate the release of interstitial volume. Consequently, we increase the dissolution capacity of LiI to 40 mol% in 75Li2S-25P2S5 glass. The synthesized glass exhibits one of the highest ionic conductivities among reported glass sulfides. Furthermore, we develop a glassy/crystalline composite electrolyte to mitigate the shortcomings of argyrodite-type sulfides by utilizing our synthesized glass as the filler. The composite electrolytes effectively mitigate Li intrusion. This work unveils a protocol for the dissolution of halogen dopants in glass electrolytes.

14.
Adv Healthc Mater ; : e2303688, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481054

RESUMO

Bacterial infections in wounds continue to be a major challenge in clinical settings worldwide and represent a significant threat to human health. This work proposes novel expandable and versatile methods for solidifying sodium alginate (SA) with metal ions (such as Fe3+ , Co2+ , Ni2+ , Cu2+ , and Zn2+ ) to create Metal-Alginate (M-Alg) hydrogel with adjustable morphology, composition, and microstructure. It conforms to the wound site, protects against second infection, reduces inflammation, and promotes the healing of infected wounds. Among these hydrogels, Cu-Alginate (Cu-Alg) shows excellent sterilization effect and good efficacy against both gram-positive and gram-negative bacteria, including multidrug-resistant (MDR) strains such as Methicillin-resistant Staphylococcus aureus (MRSA) and Carbapenem-resistant Klebsiella pneumoniae (CRKP) due to its dual antibacterial mechanisms: contact-killing and reactive oxygen species (ROS) burst. Importantly, it exhibits low cytotoxicity and biodegradability. This simple and cost-effective gel-based system has the potential to introduce an innovative approach to the management of wound infection and offers promising new perspectives for the advancement of wound care practice.

15.
Food Chem ; 447: 139006, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38492305

RESUMO

Pancreatic lipase (PL) and cholesterol esterase (CE) are vital digestive enzymes that regulate lipid digestion. Three bioactive peptides (LFCMH, RIPAGSPF, YFRPR), possessing enzyme inhibitory activities, were identified in the seed proteins of R. roxburghii. It is hypothesized that these peptides could inhibit the activities of these enzymes by binding to their active sites or altering their conformation. The results showed that LFCMH exhibited superior inhibitory activity against these enzymes compared to the other peptides. The inhibition mechanisms of the three peptides were identified as either competitive or mixed, according to inhibition models. Further studies have shown that peptides could bind to the active sites of enzymes, thus affecting their spatial conformation and restricting substrate entry into the active site. Molecular simulation further proved that hydrogen bonds and hydrophobic interactions played a vital role in the binding of peptides to enzymes. This study enriches our understanding of interaction mechanisms of peptides on PL and CE.


Assuntos
Inibidores Enzimáticos , Esterol Esterase , Inibidores Enzimáticos/farmacologia , Lipase/química , Peptídeos/farmacologia , Termodinâmica
16.
J Food Sci ; 89(4): 2450-2464, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462851

RESUMO

Fermented foods have shown promise in preventing or treating ulcerative colitis (UC) via regulating intestinal flora and correcting metabolic disorders. However, the prevention effect of fermented Wallace melon juice (FMJ) on UC is unclear. In this study, the effects of FMJ on dextran sodium sulfate (DSS)-induced UC were investigated via 16S rRNA sequencing and non-targeted metabolomics. The results showed that FMJ was effective in alleviating the symptoms of UC, reducing histological damage and oxidative stress, decreasing the levels of pro-inflammatory cytokines. After FMJ treatment, the level of propionic acid, butyric acid, and valeric acid increased by 14.1%, 44.4%, and 52.4% compared to DSS-induced UC mice. Meanwhile, the levels of harmful bacteria such as Oscillospira, Bacteroidetes, and Erysipelotrichaceae and Clostridium decreased, while the levels of beneficial bacteria such as Akkermansia, Lactobacillus, and Bifidobacterium increased. Fecal metabolomics analysis identified 31 differential metabolites, which could regulate metabolic disorders in UC mice by controlling the primary bile acid biosynthesis, purine metabolism, and pantothenate and CoA biosynthesis pathway. Additionally, the abundances of butyric acid, bile acids, and pantothenic acid were positively correlated with Allobaculum, Bifidobacterium, and other beneficial bacteria (R2 > 0.80, p < 0.01). The results indicated that FMJ played a role in regulating the structure of intestinal flora, which in turn helped in repairing metabolic disorders and alleviated colitis inflammation.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Doenças Metabólicas , Animais , Camundongos , Lactobacillus , Colite Ulcerativa/induzido quimicamente , Sulfato de Dextrana/efeitos adversos , RNA Ribossômico 16S , Ácido Butírico , Bifidobacterium , Firmicutes , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Colo
17.
Chemistry ; : e202400685, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38469986

RESUMO

Recently, chiral metal-organic coordination materials have emerged as promising candidates for a wide range of applications in chiroptoelectronics, chiral catalysis, and information encryption, etc. Notably, the chiroptical effect of coordination chromophores makes them appealing for applications such as photodetectors, OLEDs, 3D displays, and bioimaging. The direct synthesis of chiral coordination materials using chiral organic ligands or complexes with metal-centered chirality is very often tedious and costly. In the case of ionic coordination materials, the combination of chiral anions with cationic, achiral coordination compounds through noncovalent interactions may endow molecular materials with desirable chiroptical properties. The use of such a simple chiral strategy has been proven effective in inducing promising circular dichroism and/or circularly polarized luminescence signals. This concept article mainly delves into the latest advances in exploring the efficacy of such a chiral anion strategy for transforming achiral coordination materials into chromophores with superb photo- or electro-chiroptical properties. In particular, ionic small-molecular metal complexes, metal clusters, coordination supramolecular assemblies, and metal-organic frameworks containing chiral anions are discussed. A perspective on the future opportunities on the preparation of chiroptical materials with the chiral anion strategy is also presented.

18.
Langmuir ; 40(12): 6244-6252, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38482812

RESUMO

A dye-sensitized photoanode is prepared by coassembling a Ru complex photosensitizer and a Ru water oxidation catalyst (WOC) on a TiO2 substrate, in which the WOC molecules are immobilized in a layer-by-layer fashion through metal-pyridine coordination with the aid of a bifunctional anchoring and bridging molecule containing multiple pyridine groups. Under visible-light irradiation, an anodic photocurrent of around 200 µA/cm2 has been achieved with O2 and H2 being generated at the photoanode and Pt counter electrode, respectively. The pyridine anchoring strategy provides a simple method to prepare photoelectrodes for applications in photoelectrochemical cells.

19.
Sci Total Environ ; 922: 171317, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38428610

RESUMO

Sequential utilization of ozone (O3) and biological activated carbon (BAC) followed by UV/chlor(am)ine advanced oxidation process (AOP) has drawn attention in water reuse. However, the formation of disinfection by-products (DBPs) in this process is less evaluated. This study investigated the DBP formation and the relevant toxicity during the O3-BAC-UV/chlor(am)ine treatment of sand-filtered municipal secondary effluent. DBP formation in UV/chlorine and UV/dichloramine (NHCl2) processes were compared, where the impact of key operational parameters (e.g., UV wavelength, pH) on DBP formation were comprehensively evaluated. O3-BAC significantly reduced DBP formation potential (DBPFP) (58.2 %). Compared to UV/chlorine AOP, UV/NHCl2 AOP reduced DBP formation by 29.7 % in short-time treatment, while insignificantly impacting on DBPFP (p > 0.05). UV/NHCl2 AOP also led to lower calculated cytotoxicity (67.7 %) and genotoxicity (55.9 %) of DBPs compared to UV/chlorine AOP. Compared to 254 nm UV light, the utilization of 285 nm UV light decreased the formation of DBPs in wastewater treated with the UV/chlorine AOP and UV/NHCl2 AOP by 31.3 % and 19.2 %, respectively. However, the cytotoxicity and genotoxicity in UV/NHCl2 AOP using 285 nm UV light increased by 83.4 % and 58.5 %, respectively, compared to 254 nm. The concentration of DBPs formed in the UV/NHCl2 AOP at pH 8 was 54.3 % lower than that at pH 7, suggesting a better control of DBPs at alkaline condition. In the presence of bromide, UV/NHCl2 AOP tended to generate more brominated DBPs than UV/chlorine AOP. Overall, UV/NHCl2 AOP resulted in lower concentration and toxicity of DBPs compared to UV/chlorine AOP.


Assuntos
Desinfetantes , Ozônio , Poluentes Químicos da Água , Purificação da Água , Desinfecção/métodos , Carvão Vegetal , Águas Residuárias , Cloro , Raios Ultravioleta , Purificação da Água/métodos , Halogenação , Poluentes Químicos da Água/análise
20.
J Hazard Mater ; 470: 134120, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38537573

RESUMO

Numerous chlorinated disinfection by-products (DBPs) are produced during the chlorination disinfection of water. Among them, chloroacetic acids (CAAs) are of great concern due to their potential human carcinogenicity. In this study, effective electrocatalytic dechlorination of trichloroacetic acids (TCAA), a typical CAAs, was achieved in the electrochemical system with the three-dimensional (3D) self-supported CoP on cobalt foam modified by carbon nanotubes (CNT/CoP/CF) as the cathode. At a 10 mA cm-2 current density, 74.5% of TCAA (500 µg L-1) was converted into AA within 100 min. In-situ growth of CoP increased the effective electrochemical surface area of the electrode. Electrodeposited CNT promoted electron transfer from the electrode surface to TCAA. Therefore, the production of surface-adsorbed atomic hydrogen (H*) on CNT/CoP/CF was improved, further resulting in excellent electrochemical dechlorination of TCAA. The dechlorination pathway of TCAA proceeded into acetic acids via direct electronic transfer and H*-mediated reduction on CNT/CoP/CF electrode. Additionally, the electroreduction efficiency of CNT/CoP/CF for TCAA exceeded 81.22% even after 20 cycles. The highly efficient TCAA reduction performance (96.57%) in actual water revealed the potential applicability of CNT/CoP/CF in the complex water matrix. This study demonstrated that the CNT/CoP/CF is a promising non-noble metal cathode to remove chlorinated DBPs in practice.

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