Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.129
Filtrar
1.
Environ Res ; 204(Pt A): 112032, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516980

RESUMO

A novel FeVO4/BiVO4 heterojunction photocatalyst was synthesized by hydrothermal method. The FeVO4/BiVO4 nanostructures were characterized by XRD, SEM, XPS, UV-vis, and photoluminescence spectroscopy. The effects of catalyst dosage, contaminant concentration, initial hydrogen peroxide (H2O2) concentration, and pH value on the degradation of levofloxacin were investigated and several repeated experiments were conducted to evaluate the stability and reproducibility. The optimized process parameters were used for mineralization experiments. Reactive oxygen species, degradation intermediates, and possible catalytic mechanisms were also investigated. The results showed that the sonophotocatalytic performance of the FeVO4/BiVO4 heterojunction catalyst was better than that of sonocatalysis and photocatalysis. In addition, the Type II heterojunction formed by the material still had good stability in the degradation of levofloxacin after 5 cycles. The possible degradation pathway and mechanism of levofloxacin by sonophotocatalysis were put forward. This work develops new sono-photo hybrid process for potential application in the field of wastewater treatment.

2.
J Biol Chem ; : 101200, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34537242

RESUMO

As a conserved post-translational modification, SUMOylation has been shown to play important roles in chromatin-related biological processes including transcription. However, how the SUMOylation machinery associates with chromatin is not clear. Here, we present evidence that multiple SUMOylation machinery components, including SUMO E1 proteins SAE1 and SAE2 and the PIAS (protein inhibitor of activated STAT) family SUMO E3 ligases, are primarily associated with the nuclear matrix rather than with chromatin. We show using nuclease digestion that all PIAS family proteins maintain nuclear matrix association in the absence of chromatin. Importantly, we identify multiple histones including H3 and H2A.Z as directly interacting with PIAS1, and demonstrate that this interaction requires the PIAS1 SAP (SAF-A/B, Acinus, and PIAS) domain. We demonstrate that PIAS1 promotes SUMOylation of histones H3 and H2B in both a SAP domain- and an E3 ligase activity-dependent manner. Furthermore, we show that PIAS1 binds to heat shock-induced genes and represses their expression, and that this function also requires the SAP domain. Altogether, our study reveals for the first time the nuclear matrix as the compartment most enriched in SUMO E1 and PIAS family E3 ligases. Our finding that PIAS1 interacts directly with histone proteins also suggests a molecular mechanism as to how nuclear matrix-associated PIAS1 is able to regulate transcription and other chromatin-related processes.

3.
Anim Biotechnol ; : 1-6, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533414

RESUMO

White yak is a unique economic livestock animal on the Qilian Mountains of Qinghai-Tibet Plateau (QTP). Here, 369 mitochondrial D-loop sequences from three Chinese white yak breeds/populations (Tianzhu, Menyuan and Huzhu) were comprehensively analyzed to indicate their maternal genetic diversity, differentiation and phylogenetic relationship. Our results showed that the haplotype diversity (Hd) was found to be highest in Tianzhu white yak (Hd ± SD = 0.9501 ± 0.0058), while the lowest was recorded in Huzhu white yak (Hd ± SD = 0.7178 ± 0.0474). Totally, the haplotype and nucleotide diversities of white yak were 0.9407 ± 0.0069 and 0.0187 ± 0.0094, respectively, indicating an abundant maternal genetic diversity in white yak. Estimates of FST (Fixation Index) values showed a high genetic differentiation between Tianzhu and Menyuan populations (FST = 0.2928, p < 0.05) as well as that between Tianzhu and Huzhu populations (FST = 0.2721, p < 0.05), but a moderate genetic differentiation between Menyuan and Huzhu populations (FST = 0.1352, p > 0.05) was observed. Cluster analysis based on FST values among populations indicated that the genetic relationship between Menyuan and Huzhu white yak was closer, but they had a far genetic relationship with Tianzhu white yak. Maternal phylogenetic analysis revealed that white yak represented two maternal lineages (I and II), suggesting two maternal origins. In addition, it is notable that taurine mtDNA haplotypes were detected in Tianzhu and Huzhu white yak populations, indicating taurine genetic introgression to some extent. Our study would provide useful information for the conservation and utilization of white yak.

4.
Cell Death Dis ; 12(9): 847, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518519

RESUMO

Proximal tubular epithelial cells (TECs) demand high energy and rely on mitochondrial oxidative phosphorylation as the main energy source. However, this is disturbed in renal fibrosis. Acetylation is an important post-translational modification for mitochondrial metabolism. The mitochondrial protein NAD+-dependent deacetylase sirtuin 3 (SIRT3) regulates mitochondrial metabolic function. Therefore, we aimed to identify the changes in the acetylome in tubules from fibrotic kidneys and determine their association with mitochondria. We found that decreased SIRT3 expression was accompanied by increased acetylation in mitochondria that have separated from TECs during the early phase of renal fibrosis. Sirt3 knockout mice were susceptible to hyper-acetylated mitochondrial proteins and to severe renal fibrosis. The activation of SIRT3 by honokiol ameliorated acetylation and prevented renal fibrosis. Analysis of the acetylome in separated tubules using LC-MS/MS showed that most kidney proteins were hyper-acetylated after unilateral ureteral obstruction. The increased acetylated proteins with 26.76% were mitochondrial proteins which were mapped to a broad range of mitochondrial pathways including fatty acid ß-oxidation, the tricarboxylic acid cycle (TCA cycle), and oxidative phosphorylation. Pyruvate dehydrogenase E1α (PDHE1α), which is the primary link between glycolysis and the TCA cycle, was hyper-acetylated at lysine 385 in TECs after TGF-ß1 stimulation and was regulated by SIRT3. Our findings showed that mitochondrial proteins involved in regulating energy metabolism were acetylated and targeted by SIRT3 in TECs. The deacetylation of PDHE1α by SIRT3 at lysine 385 plays a key role in metabolic reprogramming associated with renal fibrosis.

5.
Cell Death Dis ; 12(9): 845, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518524

RESUMO

Tumor cells require high levels of cholesterol for membrane biogenesis for rapid proliferation during development. Beyond the acquired cholesterol from low-density lipoprotein (LDL) taken up from circulation, tumor cells can also biosynthesize cholesterol. The molecular mechanism underlying cholesterol anabolism in esophageal squamous cell carcinoma (ESCC) and its effect on patient prognosis are unclear. Dysregulation of lipid metabolism is common in cancer. Lysophosphatidylcholine acyltransferase 1 (LPCAT1) has been implicated in various cancer types; however, its role in esophageal squamous cell carcinoma (ESCC) remains unclear. In this study, we identified that LPCAT1 is highly expressed in ESCC and that LPCAT1 reprograms cholesterol metabolism in ESCC. LPCAT1 expression was negatively correlated with patient prognosis. Cholesterol synthesis in ESCC cells was significantly inhibited following LPCAT1 knockdown; cell proliferation, invasion, and migration were significantly reduced, along with the growth of xenograft subcutaneous tumors. LPCAT1 could regulate the expression of the cholesterol synthesis enzyme, SQLE, by promoting the activation of PI3K, thereby regulating the entry of SP1/SREBPF2 into the nucleus. LPCAT1 also activates EGFR leading to the downregulation of INSIG-1 expression, facilitating the entry of SREBP-1 into the nucleus to promote cholesterol synthesis. Taken together, LPCAT1 reprograms tumor cell cholesterol metabolism in ESCC and can be used as a potential treatment target against ESCC.

6.
Int Immunopharmacol ; 100: 108146, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34537481

RESUMO

BACKGROUND: Our previous studies demonstrated that autophagy alleviates cerebral I/R injury by inhibiting NLRP3 inflammasome-mediated inflammation. 6-Gingerol, a phenolic compound extracted from ginger, was reported to possess potent antiapoptotic and anti-inflammatory activities and is associated with autophagy. However, the effects of 6-Gingerol in cerebral I/R injury have not been elucidated, and whether they involve autophagy-induced NLRP3 inflammasome inhibition remains unclear. METHODS: Adult male Sprague-Dawley (SD) rats were subjected to middle cerebral artery occlusion (MCAO) for 1 h, followed by reperfusion for 24 h. 6-Gingerol and 3-methyladenine (3-MA) were injected intraperitoneally, and si-TRPV1 was injected via the lateral ventricle. Cerebral infarct volume, brain edema, neurological deficits, HE and Nissl were used to evaluate the morphological and functional changes of brain tissue, respectively. TRPV1, FAF1, autophagy related (LC3II/I, P62, Beclin1), inflammation related (NLRP3, cleaved-caspase-1, caspase-1, cleaved-IL-1ß, IL-1ß, cleaved-IL-18, IL-18) and apoptosis related (Bcl-2, Bax, cleaved-caspase-3) proteins were assessed by Western blot, immunofluorescence staining and coimmunoprecipitation, respectively. Enzyme linked immunosorbent assay (ELISA) was used to evaluate the changes in the expression levels of interleukin-1 (IL-1ß) and interleukin-18(IL-18), respectively. The degree of neuronal apoptosis was evaluated by TUNEL staining. Neuronal ultrastructure was examined by transmission electron microscopy. RESULT: 6-Gingerol treatment significantly reduced cerebral infarct volume, improved brain edema and neurological scores, and reversed brain histomorphological damage after I/R injury. In addition, 6-Gingerol significantly reduced NLRP3 inflammasome-derived inflammation and neuronal apoptosis and upregulated autophagy. The autophagy inhibitor 3-MA rescued the effects of 6-Gingerol on the NLRP3 inflammasome and apoptosis. Moreover, the findings illustrated that 6-Gingerol inhibited autophagy-induced NLRP3 inflammasome activation and apoptosis through the dissociation of TRPV1 from FAF1. CONCLUSION: In brief, 6-Gingerol exerts antiapoptotic and anti-inflammatory effects via TRPV1/FAF1 complex dissociation-mediated autophagy during cerebral I/R injury. Therefore, 6-Gingerol may be an effective drug for the treatment of I/R injury.

7.
Clin Chim Acta ; 522: 23-30, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34389280

RESUMO

Nesfatin-1, an anorexic neuropeptide discovered in 2006, is widely distributed in the central nervous system and peripheral tissues. It has been shown to be involved in the regulation of food intake and lipid metabolism, inhibiting fat accumulation, accelerating lipid decomposition, and in general, inhibiting the development of lipid-related diseases, such as obesity and metabolic syndrome. Potential mechanisms of Nesfatin-1 action in lipid metabolism and lipid-related diseases will be discussed as well as its role as a biomarker in cardiovascular disease. This review expected to provide a new strategy for the diagnosis and prevention of clinically related diseases.

8.
Cereb Cortex ; 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34379744

RESUMO

Creativity is generally defined as the ability to generate innovative thoughts that are both original and valuable. Previous studies have suggested that the temporal lobe, related to memory extraction and construction, is responsible for generating creative ideas and that the executive system supports the generation of creative ideas. However, the causal relationships between these structures and the novelty index as well as the appropriateness index of generated ideas have not been revealed. It is still largely unknown where and how original and valuable ideas are generated. In this study, the transcranial direct current stimulation technique was used to selectively manipulate the activity of the generation-related right temporoparietal junction (TPJ) (experiment 1) and the executive control-related left dorsolateral prefrontal cortex (DLPFC) (experiment 2). Then, both the novelty and appropriateness indexes of generated ideas were analyzed during insight problem-solving. The results showed that anodal stimulation of the right TPJ increased both the novelty and appropriateness indexes of creative ideas, whereas anodal stimulation of the left DLPFC increased the novelty index but not the appropriateness index of creative ideas. These findings suggest that the posterior temporal lobe takes both the novelty and appropriateness attributes into account to generate ideas, while the executive control system can effectively regulate the novelty attribute of generated ideas but ineffectively addresses the inappropriateness attribute. The current study indicates complementary mechanisms in the process of generating original and valuable ideas.

9.
Neurosci Lett ; 763: 136152, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34384845

RESUMO

Lycium ruthenicum Murray is widely used in traditional Chinese medicine and is believed to have antimicrobial, antioxidant, and anti-fatigue effects. Anthocyanins are considered to be one of the main active components. The previous work by our research team found that the anthocyanins in Lycium ruthenicum extract (ALRM) produce a stable anti-anxiety effect. The mechanisms of action include reducing the level of corticotropin-releasing factor (CRF) as well as regulating extracellular signal-regulated kinase/mitogen activation, protein kinase (ERK/MAPK) pathways, and others, all of which are related to the mechanisms of nicotine addiction. To investigate the effects of ALRM on anxiety and craving behavior after nicotine withdrawal, the components of ALRM were analyzed using the UPLC-Orbitrap MS method. The effects of ALRM on anxiety behavior induced by nicotine withdrawal were investigated in mice using the elevated plus maze (EPM) and light-dark box (LDB) tests. The effects of ALRM on craving behavior after nicotine withdrawal were further investigated using the conditional place preference (CPP) test. The EPM and LDB tests demonstrated that ALRM could alleviate the anxiety behavior induced by nicotine withdrawal and reduce nicotine craving in mice. Based on the identified ALRM components, the network pharmacology method was used to predict the mechanism of ALRM alleviating anxiety after nicotine withdrawal in mice. It was speculated that ALRM was involved in the production and transmission of dopamine, choline, and other nervous system functions and exhibited a potential role in treating nicotine addiction.

10.
Cell Death Dis ; 12(8): 792, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34392303

RESUMO

Impaired energy metabolism in proximal tubular epithelial cells (PTECs) is strongly associated with various kidney diseases. Here, we characterized proximal tubular phenotype alternations during kidney injury and repair in a mouse model of folic acid nephropathy, in parallel, identified carnitine palmitoyltransferase 1α (CPT1α) as an energy stress response accompanied by renal tubular dedifferentiation. Genetic ablation of Cpt1α aggravated the tubular injury and interstitial fibrosis and hampered kidney repair indicate that CPT1α is vital for the preservation and recovery of tubular phenotype. Our data showed that the lipid accumulation and mitochondrial mass reduction induced by folic acid were persistent and became progressively more severe in PTECs without CPT1α. Interference of CPT1α reduced capacities of mitochondrial respiration and ATP production in PTECs, and further sensitized cells to folic acid-induced phenotypic changes. On the contrary, overexpression of CPT1α protected mitochondrial respiration and prevented against folic acid-induced tubular cell damage. These findings link CPT1α to intrinsic mechanisms regulating the mitochondrial respiration and phenotype of kidney tubules that may contribute to renal pathology during injury and repair.

11.
Int Arch Allergy Immunol ; : 1-10, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34428765

RESUMO

OBJECTIVE: Rheumatoid arthritis (RA) is a kind of chronic inflammatory disease characterized by the release of inflammatory cytokines and cardiomyocyte apoptosis, which lead to increased riskfor heart diseases. This study aims to explore the possible effect and mechanism of Celastrol on RA induced cardiac impairments in rats. METHODS: Collagen induced RA wistar rat models (CIA) were established for the measurement on secondary foot swelling degree, polyarthritis index score, spleen and thymus index. Pathological morphology was observed using H&E staining. Heart fibrosis was measured after Sirius red staining, while cell apoptosis was determined by TUNEL staining. For in vitro experiments, rat cardiomyocytes were isolated to determine the inflammatory cytokine secretion and cell apoptosis using ELISA and flow cytometry, respectively. Protein expressions of related index and autophagy were detected by Western blot and immunofluorescence. RESULTS: CIA rat model was successfully established and characterized by severe secondary foot swelling degree, and increased polyarthritis index score and spleen and thymus index. Synovial hyperplasia, disordered cardiomyocytes, cell infiltration and fibrosis were also observed in CIA rat model. Compared with CIA model, Celastrol treatment could suppress the release of inflammatory cytokines, including TNF-α, IL-6, IL-1ß, as well as inhibiting the expressions of Bax, cleaved caspase3, collagen I, collagen III and α-SMA. In addition to that, Celastrol treatment can attenuate cell apoptosis and fibrosis of cardiomyocytes and elevate Bcl-2 expression. RA induced cell autophagy can be suppressed by Celastrol through inhibiting the activation of TLR2/HMGB1 signal pathway. CONCLUSION: Celastrol can regulate TLR2/HMGB1 signal pathway to suppress autophagy and therefore exert cardioprotective effect in RA.

13.
Adv Mater ; : e2103999, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34398465

RESUMO

The prostate-specific antigen (PSA) has been widely used for the early diagnosis of prostate cancer during routine check-ups. However, the low sensitivity of regular PSA tests in the PSA gray zone often means that patients are required to undergo further invasive needle biopsy for the diagnosis of prostate cancer, which may lead to potential overdiagnosis and overtreatment. In this study, a circulating tumor cell (CTC)-chip based on an evaporation-induced reduced graphene oxide (rGO) coating is presented, which enables a highly specific and non-invasive diagnosis of prostate cancer in the PSA gray zone. During the evaporation process of the rGO dispersion, the Marangoni effect induces the self-assembly of a hierarchical micro/nanowrinkled rGO coating, which can capture CTCs after subsequent surface modification of capture agents. Compared to the low diagnostic sensitivity (58.3%) of regular PSA tests, a combination of CTC detection and PSA-based hematological tests via machine-learning analysis can greatly upgrade the diagnostic sensitivity of this disease to 91.7% in clinical trial. Therefore, this study provides a non-invasive alternative with high sensitivity for the diagnosis of prostate cancer in the PSA gray zone.

14.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3364-3367, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34396756

RESUMO

Mansoa alliacea,commonly known as garlic vine,is native to the tropical rain forests of South America and widely cultivated in South China. As a popular folk medicine with various biological activities,however,this plant remains to be fully elucidated in terms of its phytochemical constituents. In this study,two new pyranonaphthoquinones were isolated from the 95% ethanol extract of the leaves and twigs of M. alliacea by various chromatographic approaches including silica gel,octadecyl silica( ODS),Sephadex LH-20,and preparative high-performance liquid chromatography( PHPLC). Their structures were determined to be 8,9-dimethoxy-α-lapachone( 1) and 7-hydroxy-8,9-dimethoxy-α-lapachone( 2) by comprehensive spectroscopic analyses and therefore respectively named as mansonin A( 1) and mansonin B( 2).


Assuntos
Compostos Fitoquímicos , Folhas de Planta , China , Cromatografia Líquida de Alta Pressão
15.
Front Endocrinol (Lausanne) ; 12: 665666, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381422

RESUMO

Background: Hepatocyte growth factor (HGF) signaling plays a plethora of roles in tumorigenesis and progression in many cancer types. As HGF activator inhibitors, serine protease inhibitor, Kunitz types 1 and 2 (SPINT1 and SPINT2) have been reported to be differentially expressed in breast cancer, but their prognostic significance and functioning mechanism remain unclear. Methods: In our study, multiple databases and bioinformatics tools were used to investigate SPINT1/2 expression profiles, prognostic significance, genetic alteration, methylation, and regulatory network in breast carcinoma. Results: SPINT1/2 expression was upregulated in breast cancer, and was relatively higher in human epidermal growth factor receptor 2 (HER2) and node positive patients. Elevated SPINT1/2 expression was significantly correlated with a poorer prognosis. Genetic alterations and SPINT1/2 hypomethylation were observed. In breast carcinoma, SPINT1/2 were reciprocally correlated and shared common co-expressed genes. Gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that their common co-expressed genes were primarily involved in regulating cell attachment and migration. Conclusions: Our study identified the expression profiles, prognostic significance and potential roles of SPINT1/2 in breast carcinoma. These study results showed that the SPINT1/2 were potential prognostic biomarker for patients with breast cancer.

16.
Multivariate Behav Res ; : 1-18, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34357822

RESUMO

The bifactor model is a promising alternative to traditional modeling techniques for studying the predictive validity of hierarchical constructs. However, no study to date has systematically examined the influence of cross-loadings on the estimation of regression coefficients in bifactor predictive models. Therefore, we present a systematic examination of the statistical performance of six modeling strategies to handle cross-loadings in bifactor predictive models: structural equation modeling (SEM), exploratory structural equation modeling (ESEM) with target rotation, Bayesian structural equation modeling (BSEM), and each of the three with augmentation. Results revealed four clear patterns: 1) forcing even small cross-loadings to zero was detrimental to empirical identification, estimation bias, power and Type I error rates; 2) the performance of ESEM with target rotation was unexpectedly weak; 3) augmented BSEM had satisfactory performance in an absolute sense and outperformed the other five strategies across most conditions; 4) augmentation improved the performance of ESEM and SEM, although the degree of improvement was not as substantial as that of BSEM. In addition, we also presented an empirical example to show the feasibility of the proposed approach. Overall, these findings can help users of bifactor predictive models design better studies, choose more appropriate analytical strategies, and obtain more reliable results. Implications, limitations, and future directions are discussed.

17.
J Relig Health ; 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34460022

RESUMO

Many loving-kindness and compassion meditation methods used in psychological research are derived from Theravada and Tibetan Buddhism. Zhiyi (), a representative figure of Chinese Buddhism, proposed a different meditation method, namely, imagination-based loving-kindness and compassion meditation. The current article introduces the imagination-based loving-kindness and compassion meditation proposed by Zhiyi and compares it with meditation methods from Theravada and Tibetan Buddhism. Zhiyi's method limits the content of imagination during meditation, which can be an essential supplement to the free association method derived from Theravada Buddhism. Zhiyi's method of helping others entirely through imagination differs significantly from the tonglen method derived from Tibetan Buddhism and may be more suitable for participants without religious beliefs. Based on Zhiyi's source text and previous psychological studies, a mental-health training program for imagination-based loving-kindness and compassion meditation is proposed. The limitations of Zhiyi's method and the future directions for empirical research on Zhiyi's method are also discussed. The differences between Zhiyi's method and other methods in terms of effects and applicable populations need to be examined in future studies.

18.
Sci Total Environ ; 801: 149611, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34428657

RESUMO

Ultrafiltration is an environmentally friendly water treatment technology, but membrane fouling significantly impacts membrane performance and service life. Photocatalytic modification of membrane is regarded as an effective way for membrane fouling control. In this study, graphite oxide (GO), Ag3PO4 and Ag3PO4-GO nanomaterials were applied in polyvinylidene fluoride (PVDF) ultrafiltration membranes modification, and the membranes was denoted as P-GO, P-AgP and P-AgP@GO, respectively. Filtration of humic acid (HA) at different operating conditions was adopted in evaluation of membrane performance. Among them, P-AgP@GO had the best permeation, rejection and antifouling performances, and could maintain excellent properties when operation conditions (HA concentration, operation pressure, pH and ionic strength) were changed. Furthermore, the effect of photocatalysis on the self-cleaning performance and its mechanism were revealed. The overall performance of P-AgP@GO could be enhanced by visible light irradiation, and extending the visible illumination time during the filtration was conducive to the reusability.

19.
Adv Mater ; : e2101259, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34292627

RESUMO

Black phosphorus (BP) is a promising anode material in lithium-ion batteries (LIBs) owing to its high electrical conductivity and capacity. However, the huge volume change of BP during cycling induces rapid capacity fading. In addition, the unclear electrochemical mechanism of BP hinders the development of rational designs and preparation of high-performance BP-based anodes. Here, a high-performance nanostructured BP-graphite-carbon nanotubes composite (BP/G/CNTs) synthesized using ball-milling method is reported. The BP/G/CNTs anode delivers a high initial capacity of 1375 mA h g-1 at 0.15 A g-1 and maintains 1031.7 mA h g-1 after 450 cycles. Excellent high-rate performance is demonstrated with a capacity of 508.1 mA h g-1 after 3000 cycles at 2 A g-1 . Moreover, for the first time, direct evidence is provided experimentally to present the electrochemical mechanism of BP anodes with three-step lithiation and delithiation using ex situ X-ray diffraction (XRD), ex situ X-ray absorption spectroscopy (XAS), ex situ X-ray emission spectroscopy, operando XRD, and operando XAS, which reveal the formation of Li3 P7 , LiP, and Li3 P. Furthermore, the study indicates an open-circuit relaxation effect of the electrode with ex situ and operando XAS analyses.

20.
J Hazard Mater ; 421: 126703, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34315026

RESUMO

Water eutrophication leads to increasingly serious harmful algal blooms (HABs), which poses tremendous threats on aquatic environment and human health. In this work, a novel magnetically separable ZnFe2O4/Ag3PO4/g-C3N4 (ZFO/AP/CN) photocatalyst with double Z-scheme was constructed for Microcystis aeruginosa (M. aeruginosa) inactivation and Microcystin-LR (MC-LR) degradation under visible light. The photocatalyst was characterized by XRD, SEM, EDS, TEM, XPS, FTIR, UV-vis, PL, and VSM. Approximately 96.33% of chlorophyll a was degraded by ZFO/AP/CN (100 mg/L) after 3 h of visible light irradiation. During the photocatalytic process, the malondialdehyde (MDA) of M. aeruginosa increased, the activities of superoxide dismutase (SOD) and catalase (CAT) increased initially and decreased afterwards. Furthermore, the photocatalytic removal efficiency of M. aeruginosa (OD680 ≈0.732) and MC-LR (0.2 mg/L) reached 94.31% and 76.92%, respectively, in the simultaneous removal of algae and algal toxin experiment. Reactive species scavenging experiments demonstrated that·O2- and·OH played key roles in inactivating M. aeruginosa and degrading MC-LR. The excellent recoverability and stability of ZFO/AP/CN were proved by cycling photocatalytic experiment which using magnetic recovery method. In summary, the synthesized magnetically separable ZFO/AP/CN photocatalyst has remarkable photocatalytic activity under visible light and shows promising potential for practical application of alleviating HABs.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...