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1.
J Environ Sci (China) ; 148: 691-701, 2025 Feb.
Article in English | MEDLINE | ID: mdl-39095201

ABSTRACT

Personal care products (PCPs) are a class of emerging pollutants that have attracted public concern owing to their harmful effects on humans and the environment. Biomonitoring data is valuable for insight the levels of PCPs in the human body and can be crucial for identifying potential health hazards. To gain a better understanding of timely exposure profiles and health risk of reproductive-age population to PCPs, we determined six parabens, six benzophenone-type ultraviolet filters, and three disinfectants in 256 urine samples collected from young adults aged 18-44 years in Beijing, China. The urinary levels of benzophenone-3 (BP-3) and 4-hydroxybenzophenone (4-OHBP) were significantly higher in summer compared to winter, suggesting these compounds have different seasonal usage patterns. Moreover, the total concentration of 15 PCPs in female was 430 ng/mL, approximately two times higher than that in male. P­chloro-m-xylenol (PCMX), as a new type of antibacterial agent, has the greatest level among all target analytes, indicating the increasingly use of this antibacterial alternative recently. Five potential influencing factors that lead to the elevated exposure level of PCPs were identified. Over 19% of the target population had a high hazard index value (greater than 1) which was attributed to exposure to propyl paraben (PrP), benzophenone-1 (BP-1), BP-3 and PCMX, indicating that PCPs may pose a relatively high exposure risk at environmental levels that should be a cause for concern.


Subject(s)
Cosmetics , Environmental Exposure , Humans , Adult , Young Adult , Risk Assessment , Female , Male , Adolescent , Cosmetics/analysis , Environmental Exposure/statistics & numerical data , Environmental Exposure/analysis , Beijing , Environmental Pollutants/analysis , Benzophenones/urine , Environmental Monitoring
2.
Materials (Basel) ; 17(18)2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39336367

ABSTRACT

The rheological behavior and printing characteristics of the screen-printing slurry for Nd-Fe-B grain boundary diffusion are key factors that determine the quality of printing and magnetic performance. However, few studies have focused on the organic medium, a crucial material for slurry. In this paper, the rheology, thixotropy, and thermal decomposition behavior of the organic vehicle in Nd-Fe-B screen printing slurry were studied. The results show that the organic vehicle formed by terpineol and polyvinyl butyral (PVB) exhibits typical non-Newtonian fluid characteristics, with excellent rheology and thixotropy, ensuring that the slurry prepared from it has excellent static stability and printing consistency. Additionally, the carbon residue of the organic vehicle formed by terpineol and PVB is less than 0.1% at 900 °C, avoiding excessive carbon entering the magnet during the diffusion process. Moreover, studying the rheology and thixotropy of the organic vehicle through a rheometer can quickly screen the slurry system. This work provides valuable guidance for designing an organic vehicle for screen-printing slurry for Nd-Fe-B grain boundary diffusion in future research.

3.
Insects ; 15(9)2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39336614

ABSTRACT

Chironomidae is a cosmopolitan and species-rich family of insects, with many species serving as useful indicators of aquatic ecosystem health. In this study, we newly sequenced six species of Kiefferulus Goetghebuer, 1922 (Chironomidae: Chironominae) by high-throughput sequencing technology. We analyzed characters of the mitochondrial genome, including the sequence length, nucleotide composition, and evolutionary rates of this genus. The size of the newly obtained sequences ranged from 15,588 to 15,767 bp, and all of them included 22 tRNAs, 13 PCGs, 2 rRNAs, and 1 CR. The CR showed the highest AT content relative to the PCGs, rRNAs, and tRNAs. Relative synonymous codon usage analysis showed that UUA, UUU, and AUU are the preferred codons. The ratio of nonsynonymous (Ka) to synonymous (Ks) substitution rates showed that all Ka/Ks of PCGs were lower than 1, with ATP8 having the highest evolution rate, while COX1 exhibited the lowest evolution rate. We reconstructed the phylogenetic relationship of the genus Kiefferulus based on eight species (six ingroups and two outgroups), using five matrices and employing Maximum likelihood and Bayesian inference approaches. Phylogenetic analysis of the Kiefferulus showed that six species within this genus were classified into a monophyletic clade.

4.
Sleep Med ; 124: 77-83, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39276701

ABSTRACT

OBJECTIVES: Primary insomnia is a substantial public health burden, but current treatments for this disorder have limited effectiveness and adherence. Herein, we aimed to investigate the efficacy and safety of continuous theta burst stimulation (cTBS) for the treatment of primary insomnia. METHODS: This two-armed, randomized, sham-controlled trial was conducted at Peking University Sixth Hospital and local community clinics. A total of 46 patients with primary insomnia were recruited and randomly allocated to either the cTBS group or sham group. Forty-one patients completed 10 sessions of cTBS or sham intervention and follow-up assessments. RESULTS: After the intervention, the severity of insomnia was significantly lower in the cTBS group than in the sham group, with a large effect size (Cohen's d = -1.938). Additionally, 52.4 % of patients in the cTBS group achieved a response (Insomnia Severity Index score reduction ≥8), whereas only 4 % of patients in the sham group achieved a response. The duration of objective total sleep time and slow-wave sleep were higher in the cTBS group than in the sham group. The degree of anxiety was lower in the cTBS group than in the sham group. There were no significant differences in depression, sleepiness, or cognitive function between the cTBS and sham groups. During follow-up, the sleep quality of the cTBS group significantly improved and remained stable at the 6-month follow-up. CONCLUSION: In this randomized clinical trial, cTBS improved insomnia symptoms and was generally well tolerated, thus supporting the further development of cTBS for the treatment of primary insomnia.

5.
Adv Mater ; : e2409025, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39267409

ABSTRACT

Monolithic integration of color-conversion materials onto blue-backlight micro-light-emitting-diodes (micro-LEDs) has emerged as a promising strategy for achieving full-color microdisplay devices. However, this approach still encounters challenges such as the blue-backlight leakage and the poor fabrication yield rate due to unsatisfied quantum dot (QD) material and fabrication process. Here, the monolithic integration of 0.39-inch micro-display screens displaying colorful pictures and videos are demonstrated, which are enabled by creating interfacial chemical bonds for wafer-scale adhesion of sub-5 µm QD-pixels on blue-backlight micro-LED wafer. The ligand molecule with chlorosulfonyl and silane groups is selected as the synthesis ligand and surface treatment material, facilitating the preparation of high-efficiency QD photoresist and the formation of robust chemical bonds for pixel integration. This is a leading record in micro-display devices achieving the highest brightness larger than 400 thousand nits, the ultrahigh resolution of 3300 PPI, the wide color gamut of 130.4% NTSC, and the ultimate performance of service life exceeding 1000 h. These results extend the mature integrated circuit technique into the manufacture of micro-display device, which also lead the road of industrialization process of full-color micro-LEDs.

6.
Nanoscale Adv ; 6(19): 4877-4884, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39323423

ABSTRACT

Large and faceted nanoparticles, such as gold bipyramids, presently require synthesis using alkyl ammonium halide ligands in aqueous conditions to stabilize the structure, which impedes subsequent transfer and suspension of such nanoparticles in low polarity solvents despite success with few nanometer gold nanoparticles of shapes such as spheres. Phase transfer methodologies present a feasible avenue to maintain colloidal stability of suspensions and move high surface energy particles into organic solvent environments. Here, we present a method to yield stable suspensions of gold bipyramids in low-polarity solvents, including methanol, dimethylformamide, chloroform, and toluene, through the requisite combination of two capping agents and the presence of a co-solvent. By utilizing PEG-SH functionalization for stability, dodecanethiol (DDT) as the organic-soluble capping agent, and methanol to aid in the phase transfer, gold bipyramids with a wide-range of aspect ratios and sizes can be transferred between water and chloroform readily and maintain colloidal stability. Subsequent transfer to various organic and low-polarity solvents is then demonstrated for the first time.

7.
RSC Adv ; 14(42): 30566-30581, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39324044

ABSTRACT

Carbon monoxide, one of the major pollutants in the air, is mainly produced due to the incomplete combustion of fossil fuels such as coal and oil. Among all the techniques developed for removing CO, catalytic oxidation has been considered one of the most effective approaches, and the commonly used catalysts include metal oxides and noble metals. Noble metal attracted extensive attention due to its good catalytic performance at low temperatures and high resistance to poisoning. The review summarizes the recent advances of noble metals including Pt, Pd, Au, Ru, Rh, and Ir in CO oxidation. The effect of support, metal doping, the particle size of noble metals, and the hydroxyl groups on CO oxidation is discussed. Besides, the metal-support interaction on the stability and activity is also involved in this review. Finally, the challenges and opportunities of supported noble metal catalysts in practical CO oxidation are proposed.

8.
Peptides ; : 171299, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39326462

ABSTRACT

The mammalian cardiac myocytes not only synthesize and secrete atrial natriuretic peptide (ANP), but also express cholecystokinin (CCK) and its receptors (CCK1R and CCK2R). However, atrial CCK expression patterns and its effects on ANP secretion during hypoxia are unclear. Therefore, this study is aimed to investigate the effect of hypoxia on the expression levels of CCK and its receptors, as well as the underlying mechanisms involved in regulating hypoxia-induced ANP secretion in isolated beating atria. The results of this study showed that acute hypoxia significantly upregulated expression of CCK and CCK1R as well as CCK2R through activation of hypoxia-inducible factor 1α-apelin signaling. Endogenous CCK induced by hypoxia markedly upregulated the expression of silent information regulator factor 2-related enzyme 1 (Sirt1) and its downstream nuclear factor erythroid­2­related factor 2 (Nrf2) via the activation of nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4), leading to increase of activating T cell factor (TCF) 3 and TCF4/ lymphoid enhancer factor (LEF) 1, ultimately promoting hypoxia-induced ANP secretion. In addition, siRNA-mediated knockdown of LEF1 dramatically attenuated hypoxia-induced increase of ANP expression in HL-1 atrial myocytes. These results indicated endogenous CCK induced by hypoxia promoted hypoxia-induced ANP secretion by activation of NOX4-Sirt1-TCF3/4-LEF1 signaling pathway.

9.
ACS Appl Mater Interfaces ; 16(38): 51575-51583, 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39276070

ABSTRACT

Holographic data storage technology is a cost-effective solution for long-term archival data storage. However, the development of suitable holographic recording materials remains a challenge. Among these materials, phenanthraquinone-doped poly(methyl methacrylate) (PQ/PMMA) stands out due to its low cost and controllable thickness. Nevertheless, its limited photosensitivity and diffraction efficiency hinder its widespread application. In order to solve these problems, we put forward a kind of convenient and simple, low cost strategy, by adding plasticizer N,N-dimethylformamide (DMF) for preparation of DMF-PQ/PMMA photopolymer, avoid the use of complex compounds. The addition of DMF not only influences the thermal polymerization stage but also forms weak interactions with PQ during the photoreaction process, thereby enhancing the holographic performance of DMF-PQ/PMMA. Consequently, we achieved a remarkable 9.1-fold increase in photosensitivity (from ∼0.35 to 3.18 cm J-1), improved diffraction efficiency by 20% (from 65% to 80%), and reduced volume shrinkage by a factor of 8 (from 0.4% to 0.05%). Furthermore, utilizing a collinear holographic storage system with multiplexing shift at a scale of 5 µm resulted in an impressively low minimum bit error rate (BER) of only 0.36% (with an average BER of 1.4%), highlighting the fast processing capability and potential for low BER applications in holographic information storage using DMF-PQ/PMMA.

10.
Inorg Chem ; 2024 Sep 26.
Article in English | MEDLINE | ID: mdl-39324751

ABSTRACT

A unique meso Ce(III)-containing antimonotungstate, {Na(OAc)(H2O)2[Ce4(tar)(Htar)2(Sb2W21O72)2(H2O)7]}244- (Ce4tar3; H4tar = tartaric acid), consisting of two enantiomeric parts with a butterfly-like configuration, was successfully synthesized by a one-pot in situ method and characterized. The coordination of d- or l-tar ligands induced the formation of Dawson-like {Ce2Sb2W21} with right or left configurations, thereby determining the d/l configurations of {Na(OAc)(H2O)2[Ce4(tar)(Htar)2(Sb2W21O72)2(H2O)7]}22-. Carboxyl groups link these two enantiomeric parts with Ce(III) ions from each other around the symmetric center of the P1̅ space group. The three types of tar ligands exhibit distinct coordination modes, and all coordinate with at least one W(VI) atom using one carboxylate oxygen atom and one α-OH. Ce4tar3 represents the largest case among those meso-dl-tar-functionalized polyoxometalates. Furthermore, Ce4tar3 exhibits excellent catalytic activity for synthesizing isoindolinones via the three-component reaction of 2-acetylbenzoic acids, amines, and phosphine oxides.

11.
Zhongguo Zhong Yao Za Zhi ; 49(16): 4437-4449, 2024 Aug.
Article in Chinese | MEDLINE | ID: mdl-39307780

ABSTRACT

Traditional Chinese medicine(TCM) placebos are simulated preparations for specific objects and the color simulation in the development of TCM placebos is both crucial and challenging. Traditionally, the prescription screening and pattern exploration process involves extensive experimentation, which is both time-consuming and labor-intensive. Therefore, accurate prediction of color simulation prescriptions holds the key to the development of TCM placebos. In this study, we efficiently and precisely predict the color simulation prescriptions of placebos using an image-based approach combined with Matlab software. Firstly, images of TCM placebo solutions are captured, and 13 chromaticity space values such as the L* a* b*, RGB, HSV, and CMYK values are extracted using Photoshop software. Correlation analysis and normalization are then performed on these extracted values to construct a 13×9×3 back propagation(BP) neural network model. Subsequently, the whale optimization algorithm(WOA) is employed to optimize the initial weights and thresholds of the BP neural network. Finally, the optimized WOA-BP neural network is validated using three representative instances. The training and prediction results indicate that, compared to the BP neural network, the WOA-BP neural network demonstrates superior performance in predicting the pigment ratios of placebos. The correlation coefficients for training, validation,testing, and the overall dataset are 0. 95, 0. 87, 0. 95, and 0. 95, respectively, approaching unity. Furthermore, all error values are reduced, with the maximum reduction reaching 99. 83%. The color difference(ΔE) values for the three validation instances are all less than 3, further confirming the accuracy and practicality of the WOA-BP neural network approach.


Subject(s)
Algorithms , Color , Drugs, Chinese Herbal , Medicine, Chinese Traditional , Neural Networks, Computer , Drugs, Chinese Herbal/chemistry , Placebos , Animals
12.
Nanoscale ; 2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39308319

ABSTRACT

Direct visualization of the states originating from electron-electron interactions is of great importance for engineering the surface and interfacial properties of graphene-based quantum materials. For instance, the rotational symmetry breaking or nematic phase inferred from spectroscopic imaging has confirmed the existence of correlated states in a wide range of moiré materials. Here, we study the atomic-scale spatial distributions and symmetry of wave functions in gate-tunable twisted double bilayer graphene by employing scanning tunneling microscopy/spectroscopy and continuum model calculations. A series of spectroscopic imaging analyses are used to identify dominant symmetry breaking of the emergent states. Interestingly, in non-integer hole fillings, a completely new localized electronic state with rotational symmetry breaking is observed on the left side of the valence flat band. The degree of anisotropy is found to increase from the conduction flat band through the valence flat band to the new state. Our results provide an essential microscopic insight into the flat band and its adjacent state for a full understanding of their electric field response in twisted graphene systems.

13.
J Biotechnol ; 395: 71-79, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39299520

ABSTRACT

Macrolactins have attracted considerable attention due to their value and application in medicine and agriculture. However, poor yields severely hinder their broader application in these fields. This study aimed to improve macrolactins production in Bacillus siamensis using a combined atmospheric and room-temperature plasma mutagenesis and a microbial microdroplet culture system. After 25 days of treatment, a desirable strain with macrolactins production 3.0-fold higher than that of the parental strain was successfully selected. The addition of 30 mg/L ZnSO4 further increased macrolactins production to 503 ± 37.6 µg/mL, representing a 30.9 % improvement in production compared to controls. Based on transcriptome analysis, the synthesis pathways of amino acids, fengycin, and surfactin were found to be downregulated in IMD4036. Further fermentation experiments confirmed that inhibition of the comparative fengycin synthesis pathway was potentially driving the increased production of macrolactins. The strategies and possible mechanisms detailed in this study can provide insight into enhancing the production of other secondary metabolites toxic to the producer strains.

15.
Front Public Health ; 12: 1423286, 2024.
Article in English | MEDLINE | ID: mdl-39220462

ABSTRACT

Background: Limited epidemiological evidence suggests that exposure to trace elements adversely impacts the development of gastric precancerous lesions (GPL) and gastric cancer (GC). This study aimed to estimate the association of individual urinary exposure to multiple elements with GPL and GC. Methods: A case-control investigation was conducted in Anhui Province from March 2021 to December 2022. A total of 528 subjects (randomly sampled from 1,020 patients with GPL, 200 patients with GC, and 762 normal controls) were included in our study. Urinary levels of iron (Fe), copper (Cu), zinc (Zn), nickel (Ni), strontium (Sr), and Cesium (Cs) were measured using inductively coupled plasma mass spectrometry (ICP-MS). Four different statistical approaches were employed to explore the risk of GPL and GC with mixed exposure, including multivariate logistic regression, weighted quantile regression (WQS), quantile g-computation (Qgcomp), and the Bayesian kernel machine regression (BKMR) model. Results: The WQS model indicated that urinary exposure to a mixture of elements is positively correlated with both GPL and GC, with ORs for the mixture exposure of 1.34 (95% CI: 1.34-1.61) for GPL and 1.38 (95% CI: 1.27-1.50) for GC. The Qgcomp and BKMR models also demonstrated a statistically significant positive correlation between the mixture and both GPL and GC. Conclusion: Considering the limitations of case-control studies, future prospective studies are warranted to elucidate the combined effects and mechanisms of trace elements exposure on human health.


Subject(s)
Precancerous Conditions , Stomach Neoplasms , Trace Elements , Humans , Stomach Neoplasms/urine , Stomach Neoplasms/epidemiology , China/epidemiology , Male , Trace Elements/urine , Female , Case-Control Studies , Middle Aged , Precancerous Conditions/urine , Aged , Adult
16.
Ying Yong Sheng Tai Xue Bao ; 35(7): 1771-1778, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39233405

ABSTRACT

Litter layer, serving as the "skin" of forest soil, plays a crucial role in conserving water resources and maintaining soil and water conservation. We analyzed the relationship of tree species richness, community weighted mean traits, and functional diversity with the standing mass, maximum water holding rate, and effective water sto-rage capacity of litters from various tree species including Liquidambar formosana, Mytilaria laosensis, Castanopsis sclerophylla, Castanopsis hystrix, Cunninghamia lanceolata, Pinus massoniana, Fokienia hodginsii, Taxus wallichiana and their combinations of mixed forests in subtropical region. The results showed that across various tree species combinations, the ranges of maximum water holding rate, standing litter mass and effective water storage capacity of undecomposed layer were 0-419%, 0-0.58 t·hm-2, and 0-1.66 t·hm-2, respectively. For the semi-decomposition layer, these values spanned in 0-375%, 0-6.14 t·hm-2, and 0-16.03 t·hm-2, respectively. Tree species richness and community weighted mean specific leaf area had significantly positive effects on standing mass of litter and effective water storage capacity, while community weighted mean leaf N content had significantly negative effect on standing mass of litter. The maximum water holding rate increased with the increases of functional diversity of specific leaf area and community weighted mean specific leaf area, decreased with the increase of community weighted mean leaf thickness. Results of structural equation model showed that tree species richness increased litter water holding capacity by increasing functional diversity of specific leaf area. The community weighted mean specific leaf area increased the water holding capacity of litter layer by increasing standing mass of litter and the maximum water holding rate. It is necessary to consider planting mixed forest with higher community weighted mean specific leaf area in the management of subtropical artificial forest, so as to improve the water holding capacity of litter layer.


Subject(s)
Biodiversity , Plant Leaves , Soil , Trees , Tropical Climate , Water , Trees/growth & development , Trees/classification , Water/analysis , China , Plant Leaves/growth & development , Soil/chemistry , Forests
17.
Bioact Mater ; 42: 52-67, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39280584

ABSTRACT

Vascular calcification and vascular ageing are "silent" diseases but are highly prevalent in patients with end stage renal failure and type 2 diabetes, as well as in the ageing population. Melatonin (MT) has been shown to induce cardiovascular protection effects. However, the role of MT on vascular calcification and ageing has not been well-identified. In this study, the aortic transcriptional landscape revealed clues for MT related cell-to-cell communication between endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) in vascular calcification and vascular ageing. Furthermore, we elucidated that it was exosomes that participate in the information transportation from ECs to VSMCs. The exosomes secreted from melatonin-treated ECs (MT-ECs-Exos) inhibited calcification and senescence of VSMCs. Mechanistically, miR-302d-5p was highly enriched in MT-ECs-Exos, while depletion of miR-302d-5p blocked the ability of MT-ECs-Exos to suppress VSMC calcification and senescence. Notably, Wnt3 was a bona fide target of miR-302d-5p and modulated VSMC calcification and senescence. Furthermore, we found that maturation of endothelial derived exosomal miR-302d-5p was promoted by WTAP in an N6-methyladenosine (m6A)-dependent manner. Interestingly, MT alleviated vascular calcification and ageing in 5/6-nephrectomy (5/6 NTP) mice, a chronic kidney disease (CKD) induced vascular calcification and vascular ageing mouse model. MT-ECs-Exos was absorbed by VSMCs in vivo and effectively prevented vascular calcification and ageing in 5/6 NTP mice. ECs-derived miR-302d-5p mediated MT induced anti-calcification and anti-ageing effects in 5/6 NTP mice. Our study suggests that MT-ECs-Exos alleviate vascular calcification and ageing through the miR-302d-5p/Wnt3 signaling pathway, dependent on m6A methylation.

18.
Article in English | MEDLINE | ID: mdl-39227495

ABSTRACT

Local anesthetics, such as ropivacaine (Ropi), are toxic to nerve cells. We aimed to explore the role of forkhead box O3 (FOXO3) in Ropi-induced nerve injury to provide a theoretical basis for reducing the anesthetic neurotoxicity. SK-N-SH cells were cultured and treated with different concentrations of Ropi. Cell viability, apoptosis, cytotoxicity (LDH/ROS/SOD), and levels of FOXO3, miR-126-5p, and tumor necrosis factor receptor-associated factor 6 (TRAF6) were detected. The enrichment of FOXO3 on the miR-126-5p promoter was analyzed. The binding relationships among FOXO3, miR-126-5p promoter sequence, and TRAF6 3'UTR sequence were verified. Combined experiments detected the regulatory role of FOXO3/miR-126-5p/TRAF6 in Ropi-induced nerve injury. FOXO3 was upregulated in Ropi-induced nerve cell damage. Inhibition of FOXO3 ameliorated Ropi-induced decreased cell viability, and increased apoptosis and cytotoxicity. FOXO3 bound to the miR-126-5p promoter and inhibited its expression, thereby counteracting miR-126-5p-induced repression. miR-126-5p inhibition and TRAF6 overexpression partially reversed the alleviative effect of FOXO3 inhibition on Ropi-induced nerve cell damage. In conclusion, FOXO3 aggravated the neurotoxicity of Ropi through miR-126-5p downregulation and TRAF6 upregulation, suggesting that FOXO3 inhibitor could be an adjuvant agent for local anesthetics, to alleviate local anesthetics-induced neurotoxicity.

19.
Carbohydr Polym ; 346: 122616, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39245526

ABSTRACT

Traditional Fenton principles for degrading polysaccharides, including chondroitin sulfate (CS), are fraught with limitations, such as strict pH-dependence, higher temperature requirements, desulfurization, and environmentally perilous. In this study, an effective Fenton-like system comprising trimetallic-doped carbon nitride material (tri-CN) with hydrogen-bonded melamine-cyanuric acid (MCA) supramolecular aggregates as its basic skeleton was engineered to overcome the challenges of traditional methods. Detailed material characterizations revealed that, compared to monometallic-doped or bimetallic-doped counterparts, tri-CN offered a larger surface area, higher porosity, and increased metal loading, thereby enhancing reactant accessibility and polysaccharide degradation efficiency. The characterization and activity assessment of the degraded polysaccharide revealed structurally intact products without significant desulfurization, indicating the effectiveness of the designed approach. Moreover, the degraded chondroitin sulfate CS3 catalyzed by tri-CN, exhibited promising antioxidant activity and anti-CRISPR potential. The results elucidated that the high-valent iron species in the material served as primary active sites, catalyzing the cleavage of hydrogen peroxide to generate hydroxyl radicals that subsequently attacked CS chains, leading to their fragmentation. Hence, the designed material can be efficiently applied to polysaccharide degradation, but not limited to photocatalysis, electrocatalysis, sensor, energy storage materials, and wastewater treatment.

20.
Adv Mater ; : e2406608, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39246123

ABSTRACT

Smart memristors with innovative properties are crucial for the advancement of next-generation information storage and bioinspired neuromorphic computing. However, the presence of significant sneak currents in large-scale memristor arrays results in operational errors and heat accumulation, hindering their practical utility. This study successfully synthesizes a quasi-free-standing Bi2O2Se single-crystalline film and achieves layer-controlled oxidation by developing large-scale UV-assisted intercalative oxidation, resulting ß-Bi2SeO5/Bi2O2Se heterostructures. The resulting ß-Bi2SeO5/Bi2O2Se memristor demonstrates remarkable self-rectifying resistive switching performance (over 105 for ON/OFF and rectification ratios, as well as nonlinearity) in both nanoscale (through conductive atomic force microscopy) and microscale (through memristor array) regimes. Furthermore, the potential for scalable production of self-rectifying ß-Bi2SeO5/Bi2O2Se memristor, achieving sub-pA sneak currents to minimize cross-talk effects in high-density memristor arrays is demonstrated. The memristors also exhibit ultrafast resistive switching (sub-100 ns) and low power consumption (1.2 pJ) as characterized by pulse-mode testing. The findings suggest a synergetic effect of interfacial Schottky barriers and oxygen vacancy migration as the self-rectifying switching mechanism, elucidated through controllable ß-Bi2SeO5 thickness modulation and theoretical ab initio calculations.

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