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1.
J Nutr ; 154(6): 1853-1860, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38614238

RESUMO

BACKGROUND: Obesity paradox has been reported in patients with cardiovascular disease, showing an inverse association between obesity as defined by BMI (in kg/m2) and prognosis. Nutritional status is associated with systemic inflammatory response and affects cardiovascular disease outcomes. OBJECTIVES: This study sought to examine the influence of obesity and malnutrition on the prognosis of patients with acute coronary syndrome (ACS). METHODS: This study included consecutive patients diagnosed with ACS and underwent coronary angiogram between January 2009 and February 2023. At baseline, patients were categorized according to their BMI as follows: underweight (<18), normal weight (18-24.9), overweight (25.0-29.9), and obese (>30.0). We assessed the nutritional status by Prognostic Nutritional Index (PNI). Malnutrition was defined as a PNI value of <38. RESULTS: Of the 21,651 patients with ACS, 582 (2.7%) deaths from any cause were observed over 28.7 months. Compared with the patient's state of normal weight, overweight, and obesity were associated with decreased risk of all-cause mortality. Malnutrition was independently associated with poor survival (hazards ratio: 2.64; 95% CI: 2.24, 3.12; P < 0.001). In malnourished patients, overweight and obesity showed a 39% and 72% reduction in the incidence of all-cause mortality, respectively. However, in nourished patients, no significant reduction in the incidence of all-cause mortality was observed (all P > 0.05). CONCLUSIONS: Obesity paradox appears to occur in patients with ACS. Malnutrition may be a significant independent risk factor for prognosis in patients with ACS. The obesity paradox is influenced by the status of malnutrition.


Assuntos
Síndrome Coronariana Aguda , Desnutrição , Obesidade , Humanos , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/mortalidade , Masculino , Feminino , Desnutrição/complicações , Obesidade/complicações , Pessoa de Meia-Idade , Idoso , Índice de Massa Corporal , Estado Nutricional , Prognóstico , Fatores de Risco , Avaliação Nutricional , Paradoxo da Obesidade
2.
Clin Interv Aging ; 19: 571-579, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545251

RESUMO

Background: Rate-pressure product (RPP) calculated by multiplying heart rate by systolic blood pressure, is a convenient indicator closely associated with cardiac work or myocardial oxygen consumption. It has been reported to relate strongly to important indices of cardiovascular risk in patients with myocardial ischemia. However, its relationship with short- and long-term mortality in patients with acute coronary syndrome (ACS) undergoing primary PCI/immediate invasive strategy has not been defined. Methods: This study analyzed 1301 consecutive ACS patients who had undergone primary PCI, between January 2018 and September 2021. Patients with systolic BP < 90 mmHg were excluded to avoid the confounding effect of cardiogenic shock. RPP values were collected on admission and were divided into four groups: RPP ≤ 7.4, 7.4 ≤ 8.8, 8.8 <8.8 < RPP8, and RPP > 10.8. Clinical endpoints were in-hospital cardiac and long-term all-cause mortality. The predictive performance was assessed by C-statistic, multivariate analysis and survival analysis. Results: Multivariate analysis showed that these in the highest vs lowest category of RPP (>10.8 vs ≤7.4) had OR of 4.33 (95% CI=1.10 -17.01; P = 0.036) in in-hospital cardiac mortality and 3.15 (95% CI=1.24 -8.00; P = 0.016) in long-term all-cause mortality. In C-statistic analyses, RPP was a strong predictor in ACS, STEMI or UA/NSTEMI group for in-hospital cardiac mortality (AUC = 0.746, 95% CI = 0.722-0.770, p < 0.001) and long-term all-cause mortality (AUC = 0.701, 95% CI = 0.675-0.725, p < 0.001). The Kaplan-Meier event rate for long-term survival of RPP > 10.8 was significantly lower than that of RPP ≤ 10.8. Conclusion: RPP showed a positive association with in-hospital cardiac or long-term all-cause mortality in ACS patients undergoing primary PCI/immediate invasive strategy, and RPP > 10.8 can be as an independent predictor.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Isquemia Miocárdica , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Síndrome Coronariana Aguda/cirurgia , Mortalidade Hospitalar , Fatores de Risco , Resultado do Tratamento
5.
Clin Res Cardiol ; 113(5): 761-769, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38197895

RESUMO

BACKGROUND: Whether heart failure with preserved ejection fraction (HFpEF) is associated with an increased risk of developing systolic dysfunction and a poor prognosis in hypertrophic cardiomyopathy (HCM) patients is unknown. OBJECTIVE: We aimed to assess risk factors for the development of end-stage (ES) heart failure (HF) (ejection fraction < 50%) and compare the prognosis of different HF phenotypes. METHODS: This retrospective study was conducted on patients with HCM in China between January 2009 and February 2023. Patients were stratified into three different groups: HCM-non-HF, HCM-HFpEF and HCM-heart failure with reduced ejection fraction (HCM-HFrEF). The primary outcome was a composite of major adverse cardiac events (MACEs), including all-cause deaths, HF hospitalization, sudden cardiac death and ventricular tachycardia. RESULTS: Of 3,620 HCM patients enrolled, 1,553 (42.9%) had non-HF, 1,666 (46.0%) had HFpEF, and 579 patients (11.1%) had HFrEF at baseline. During the median follow-up period of 4.0 years (IQR 1.4-9.4 years), patients with HCM-HFpEF exhibited a higher incidence of ES-HF than those with HCM-non-HF (12.4% vs. 2.7%, P < 0.001). HFpEF was an independent risk factor for ES-HF development (HR 3.84, 2.54-5.80, P < 0.001). MACEs occurred in 26.9% with a higher incidence in HCM-HFpEF than HCM-non-HF (36.6% vs 12.2%, P < 0.001). HFpEF was an independent predictor of MACEs (HR 2.13, 1.75-2.59, P < 0.001). CONCLUSIONS: HFpEF is common in HCM. Compared to non-HF, it increases the risk of LVEF decline and poor prognosis. It may aid in risk stratification and need close echocardiography follow-up.


Assuntos
Cardiomiopatia Hipertrófica , Insuficiência Cardíaca , Humanos , Volume Sistólico , Estudos Retrospectivos , Prognóstico , Cardiomiopatia Hipertrófica/complicações , Função Ventricular Esquerda
6.
J Am Heart Assoc ; 13(3): e032997, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38240197

RESUMO

BACKGROUND: Systemic chronic inflammation plays a role in the pathophysiology of both heart failure with preserved ejection fraction (HFpEF) and metabolic dysfunction-associated fatty liver disease. This study aimed to investigate whether serum hs-CRP (high-sensitivity C-reactive protein) levels were associated with the future risk of heart failure (HF) hospitalization in patients with metabolic dysfunction-associated fatty liver disease and a normal left ventricular ejection fraction. METHODS AND RESULTS: The study enrolled consecutive individuals with metabolic dysfunction-associated fatty liver disease and normal left ventricular ejection fraction who underwent coronary angiography for suspected coronary heart disease. The study population was subdivided into non-HF, pre-HFpEF, and HFpEF groups at baseline. The study outcome was time to the first hospitalization for HF. In 10 019 middle-aged individuals (mean age, 63.3±10.6 years; 38.5% women), the prevalence rates of HFpEF and pre-HFpEF were 34.2% and 34.5%, with a median serum hs-CRP level of 4.5 mg/L (interquartile range, 1.9-10 mg/L) and 5.0 mg/L (interquartile range, 2.1-10.1 mg/L), respectively. Serum hs-CRP levels were significantly higher in the pre-HFpEF and HFpEF groups than in the non-HF group. HF hospitalizations occurred in 1942 (19.4%) patients over a median of 3.2 years, with rates of 3.7% in non-HF, 20.8% in pre-HFpEF, and 32.1% in HFpEF, respectively. Cox regression analyses showed that patients in the highest hs-CRP quartile had a ≈4.5-fold increased risk of being hospitalized for HF compared with those in the lowest hs-CRP quartile (adjusted-hazard ratio, 4.42 [95% CI, 3.72-5.25]). CONCLUSIONS: There was a high prevalence of baseline pre-HFpEF and HFpEF in patients with metabolic dysfunction-associated fatty liver disease and suspected coronary heart disease. There was an increased risk of HF hospitalization in those with elevated hs-CRP levels.


Assuntos
Doença das Coronárias , Insuficiência Cardíaca , Hepatopatia Gordurosa não Alcoólica , Pessoa de Meia-Idade , Humanos , Feminino , Idoso , Masculino , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Proteína C-Reativa , Angiografia Coronária , Prognóstico , Hospitalização
8.
Chemistry ; 29(52): e202301469, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37385953

RESUMO

In this work, an organic-inorganic hybrid crystal, violet-crystal (VC), was used to etch the nickel foam (NF) to fabricate a self-standing electrode for the water oxidation reaction. The efficacy of VC-assisted etching manifests the promising electrochemical performance towards the oxygen evolution reaction (OER), requiring only ~356 and ~376 mV overpotentials to reach 50 and 100 mA cm-2 , respectively. The OER activity improvement is attributed to the collectively exhaustive effects arising from the incorporation of various elements in the NF, and the enhancement of active site density. Furthermore, the self-standing electrode is robust, exhibiting a stable OER activity after 4,000 cyclic voltammetry cycles, and ~50 h. The anodic transfer coefficients (αa ) show that the first electron transfer step is the rate-determining step on the surface of NF-VCs-1.0 (NF etched by 1 g of VCs) electrode, while the chemical step involving dissociation following the first electron transfer step is identified as the rate-limiting step in other electrodes. The lowest Tafel slope value observed in the NF-VCs-1.0 electrode indicates the high surface coverage of oxygen intermediates and more favorable OER reaction kinetics, as confirmed by high interfacial chemical capacitance and low charge transport/interfacial resistance. This work demonstrates the importance of VCs-assisted etching of NF to activate the OER, and the ability to predict reaction kinetics and rate-limiting step based on αa values, which will open new avenues to identify advanced electrocatalysts for the water oxidation reaction.

9.
Hepatol Int ; 17(4): 773-791, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37204656

RESUMO

BACKGROUND: Fatty liver disease in the absence of excessive alcohol consumption is an increasingly common condition with a global prevalence of ~ 25-30% and is also associated with cardiovascular disease (CVD). Since systemic metabolic dysfunction underlies its pathogenesis, the term metabolic (dysfunction)-associated fatty liver disease (MAFLD) has been proposed for this condition. MAFLD is closely intertwined with obesity, type 2 diabetes mellitus and atherogenic dyslipidemia, which are established cardiovascular risk factors. Unlike CVD, which has received attention in the literature on fatty liver disease, the CVD risk associated with MAFLD is often underestimated, especially among Cardiologists. METHODS AND RESULTS: A multidisciplinary panel of fifty-two international experts comprising Hepatologists, Endocrinologists, Diabetologists, Cardiologists and Family Physicians from six continents (Asia, Europe, North America, South America, Africa and Oceania) participated in a formal Delphi survey and developed consensus statements on the association between MAFLD and the risk of CVD. Statements were developed on different aspects of CVD risk, ranging from epidemiology to mechanisms, screening, and management. CONCULSIONS: The expert panel identified important clinical associations between MAFLD and the risk of CVD that could serve to increase awareness of the adverse metabolic and cardiovascular outcomes of MAFLD. Finally, the expert panel also suggests potential areas for future research.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Hepatopatias , Hepatopatia Gordurosa não Alcoólica , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Ásia , Consenso
10.
J Am Heart Assoc ; 12(8): e029070, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37066808

RESUMO

Background Patients with left ventricular thrombus (LVT) resolution can have LVT recurrence and risk for thromboembolism. However, these outcomes after LVT resolution are not well known. We aimed to assess the prevalence, risk factors, and clinical outcomes for LVT recurrence in patients with LVT resolution to inform follow-up and treatment. Methods and Results Patients with LVT resolution were identified retrospectively from a large echocardiography database between January 2009 and May 2022. Participants had echocardiograms at 3 time points, including baseline at LVT diagnosis, at LVT resolution, and a follow-up for identification of LVT recurrence. The cumulative LVT recurrence rate was estimated by the Kaplan-Meier method, and predictors of LVT recurrence were evaluated using Cox regression analysis. Among 115 patients with LVT resolution, 28 (24.3%) had LVT recurrence at a median follow-up of 1.2 (0.5-2.8) years. LV aneurysm (hazard ratio [HR], 2.59 [95% CI, 1.20-5.58], P=0.015) and anticoagulant use (HR, 0.12 [95% CI, 0.04-0.41], P=0.001) were predictors of LVT recurrence on multivariable analysis. Patients with an LV aneurysm who did not receive any anticoagulation demonstrated an LVT recurrence rate of 69.5%, whereas those without an LV aneurysm who received anticoagulation had a recurrence rate of 0%. Patients with LVT recurrence had a higher incidence of an embolic event (10.7% versus 1.1%, P=0.016). Conclusions LVT recurrence after LVT resolution is common, especially in those with an LV aneurysm, and is associated with a higher embolic risk. Continued anticoagulation is protective against LVT recurrence, although bleeding risk needs to be considered. These findings can inform follow-up and treatment of patients with documented LVT resolution.


Assuntos
Tromboembolia , Trombose , Humanos , Anticoagulantes/uso terapêutico , Estudos Retrospectivos , Trombose/diagnóstico por imagem , Trombose/tratamento farmacológico , Trombose/epidemiologia , Tromboembolia/tratamento farmacológico , Coagulação Sanguínea
11.
ACS Appl Mater Interfaces ; 15(10): 12908-12914, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36867502

RESUMO

As an emerging energy storage concept, Al-CO2 batteries have not yet been demonstrated as a rechargeable system that can deliver a high discharge voltage and a high capacity. In this work, we present a homogeneous redox mediator to access a rechargeable Al-CO2 battery with an ultralow overpotential of 0.05 V. In addition, the resulting rechargeable Al-CO2 cell can maintain a high discharge voltage of 1.12 V and delivers a high capacity of 9394 mAh/gcarbon. Nuclear magnetic resonance (NMR) analysis indicates that the discharge product is aluminum oxalate which can facilitate the reversible operation of Al-CO2 batteries. The rechargeable Al-CO2 battery system demonstrated here holds great promise as a low-cost and high-energy alternative for future grid energy storage applications. Meanwhile, the Al-CO2 battery system could facilitate capture and concentration of atmospheric CO2, ultimately benefiting both the energy and environmental sectors of society.

12.
Front Neurosci ; 17: 1144421, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891459

RESUMO

Purpose: To explore the possible molecular mechanism by which epidermal growth factor-containing fibulin-like extracellular matrix protein 1 (EFEMP1) regulates choroid thickness (CT) in the development of myopia. Methods: In total, 131 subjects were divided into the emmetropia (EM) group, non-high myopia (non-HM) group and high myopia (HM) group. Their age, refraction, intraocular pressure, and other ocular biometric parameters were collected. A 6 × 6 mm area centered on the optic disc was scanned by coherent optical tomography angiography (OCTA) to measure CT, and the tear concentrations of EFEMP1 were quantified using enzyme-linked immunosorbent assay (ELISA) analysis. Twenty-two guinea pigs were divided into the control group and the form-deprivation myopia (FDM) group. The right eye of the guinea pig in the FDM group was covered for 4 weeks, and the diopter and axial length of the right eye of the guinea pig were measured before and after the treatment. After the measurement, the guinea pig was euthanized, and the eyeball was removed. Quantitative reverse transcription polymerase chain reaction, western blotting assays and immunohistochemistry were used to assess the expression of EFEMP1 in the choroid. Results: There were significant differences in CT among the three groups (p < 0.001). CT was positively correlated with age in HM (r = -0.3613, p = 0.0021), but no significant correlation with SE (p > 0.05) was observed. Furthermore, there were increased levels of EFEMP1 in the tears of myopic patients. After 4 weeks of covering the right eye of the FDM guinea pigs, there was a significant increase in axial length and a decrease in diopter (p < 0.05). The mRNA and protein expression of EFEMP1 was significantly increased in the choroid. Conclusion: Choroidal thickness was significantly thinner in myopic patients, and the expression level of EFEMP1 in the choroid increased during the development of FDM. Therefore, EFEMP1 may be involved in the regulation of choroidal thickness in myopia patients.

13.
J Clin Med ; 12(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36769499

RESUMO

The optimal antithrombotic strategy after percutaneous left atrial appendage closure (LAAC) has not yet been established. The advisability of administering low-dose direct oral anticoagulation after LAAC to patients at high risk of bleeding is uncertain. Thus, in the present study, we evaluated the safety and effectiveness of reduced-(15 mg) or half-dose rivaroxaban (10 mg) versus warfarin regarding real-world risks of thromboembolism, bleeding, and device-related thrombosis (DRT) after LAAC. Patients with non-valvular atrial fibrillation and HASBLED ≥ 3 who had undergone successful LAAC device implantation from October 2014 to April 2020 were screened and those who had received 10 mg or 15 mg rivaroxaban or warfarin therapy were enrolled. The patients were followed up 45 days and 6 months after LAAC to evaluate outcomes, including death, thromboembolism, major bleeding, and DRT. Of 457 patients with HASBLED ≥ 3 who had undergone LAAC, 115 had received warfarin and 342 rivaroxaban (15 mg: N = 164; 10 mg: N = 178). There were no significant differences in the incidence of thromboembolism or DRT between the warfarin and both doses of rivaroxaban groups (all p > 0.05). The incidence of major bleeding was significantly higher in the warfarin group than in either the reduced- or half-dose rivaroxaban groups (warfarin vs. rivaroxaban 15 mg: 2.6% vs. 0%, p = 0.030; warfarin vs. rivaroxaban 10 mg: 2.6% vs. 0%, p = 0.038). Either reduced- or half-dose rivaroxaban may be an effective and safe alternative to warfarin therapy in patients with LAAC and who are at high risk of bleeding, the risk of thromboembolism being similar and of major bleeding lower for both doses of rivaroxaban.

14.
Polymers (Basel) ; 15(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36679233

RESUMO

Tetrakis(dialkylamino)phosphonium (TKDAAP) compounds exhibit extraordinary base resistance, a prerequisite feature for high-performance anion exchange membranes (AEMs). It is, however, challenging to synthesize a TKDAAP compound with reactive functionality that can be used to link the cation to a polymer backbone. In this study, two TKDAAP compounds with alkyne functionality were synthesized and incorporated into an azide-modified SBS triblock copolymer backbone via Cu(I)-catalyzed alkyne-azide cycloaddition (CuAAC) "click" chemistry. The properties of the resulting AEMs were characterized. It was found that (1) the triazole linker between the cation and the polymer backbone was stable under alkaline conditions; (2) varying the substituents of TKDAAP compounds could dramatically alter the stability; and (3) increasing the hydrophilicity of the AEM was an efficient way to enhance its ionic conductivity. Using clickable TKDAAP compounds makes it easy to combine various cations into polymer backbones with adjustable cation content, thus potentially leading to an efficient way to screen a wide variety of polyelectrolyte structures to identify the most promising candidates for high-performance AEMs.

15.
Cardiovasc Diabetol ; 21(1): 270, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463192

RESUMO

The newly proposed term "metabolic dysfunction-associated fatty liver disease" (MAFLD) is replacing the old term "non-alcoholic fatty liver disease" (NAFLD) in many global regions, because it better reflects the pathophysiology and cardiometabolic implications of this common liver disease. The proposed change in terminology from NAFLD to MAFLD is not simply a single-letter change in an acronym, since MAFLD is defined by a set of specific and positive diagnostic criteria. In particular, the MAFLD definition specifically incorporates within the classification recognized cardiovascular risk factors. Although convincing evidence supports a significant association between both NAFLD and MAFLD, with increased risk of CVD morbidity and mortality, neither NAFLD nor MAFLD have received sufficient attention from the Cardiology community. In fact, there is a paucity of scientific guidelines focusing on this common and burdensome liver disease from cardiovascular professional societies. This Perspective article discusses the rationale and clinical relevance for Cardiologists of the newly proposed MAFLD definition.


Assuntos
Cardiologia , Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Fatores de Risco , Fatores de Risco de Doenças Cardíacas
16.
Proc Natl Acad Sci U S A ; 119(45): e2203256119, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36322760

RESUMO

The next generation of fuel cells, electrolyzers, and batteries requires higher power, faster kinetics, and larger energy density, which necessitate the use of compositionally complex oxides to achieve multifunctionalities and activity. These compositionally complex oxides may change their phases and structures during an electrochemical process-a so-called "electrochemically driven phase transformation." The origin for such a phase change has remained obscure. The aim of this paper is to present an experimental study and a theoretical analysis of phase evolution in praseodymium nickelates. Nickelate-based electrodes show up to 60 times greater phase transformation during operation when compared with thermally annealed ones. Theoretical analysis suggests that the presence of a reduced oxygen partial pressure at the interface between the oxygen electrode and the electrolyte is the origin for the phase change in an oxygen electrode. Guided by the theory, the addition of the electronic conduction in the interface layer leads to the significant suppression of phase change while improving cell performance and performance stability.


Assuntos
Fontes de Energia Elétrica , Óxidos , Óxidos/química , Eletrodos , Eletrólitos/química , Oxigênio/química
17.
Ecotoxicol Environ Saf ; 242: 113849, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35809394

RESUMO

Groundwater may contain radioactive substances which can be dangerous to human health. Concentrations of natural radionuclides polonium (Po), thorium (Th), uranium (U), and radium (Ra) isotopes were measured in groundwater samples collected from different locations in the vicinity of the Waste Isolation Pilot Plant (WIPP) site in Carlsbad, New Mexico. The average values of gross activity concentrations of 210Po, 228Th, 238U, 234U, 226Ra and 228 Ra isotopes were determined to be 1.62 Bq L-1 in shallow groundwater and 5.88 Bq L-1 in deep groundwater, respectively. The total radioactivity in deep groundwater was higher than that in shallow groundwater, and most of the radioactivity in the water is from 226Ra. Furthermore, the effective doses for ingestion of natural radionuclides were about 0.333 mSv y-1 for shallow groundwater and about 1.338 mSv y-1 for deep groundwater samples, which are higher than the World Health Organization (WHO, 2017) guideline level (0.1 mSv y-1) for drinking water. Ra dominated the total ingestion dose, contributing 93.06 % and 75.40 % of the total effective doses to the deep and shallow groundwater, respectively. The ingrowth and decay of natural radionuclides suggested that 228Ra/226Ra ratio can be a useful indicator of the source of radioactive contamination. The radioactivity data obtained from the investigated groundwater samples can be used to establish a baseline for radioactivity levels in groundwater around the WIPP site.


Assuntos
Água Subterrânea , Polônio , Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Urânio , Poluentes Radioativos da Água , Humanos , Polônio/análise , Radioisótopos/análise , Rádio (Elemento)/análise , Tório/análise , Urânio/análise , Poluentes Radioativos da Água/análise
18.
J Colloid Interface Sci ; 626: 836-847, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35820218

RESUMO

Electrochemical reduction of carbon dioxide (ERCO2) allows for the conversion of CO2 to value-added low-carbon chemicals. Catalysts are indispensable for an efficient ERCO2 process. In this work, a Sn-based metal-organic framework (Sn-MOF) was synthesized as an electrocatalyst for the conversion of CO2 to formate (HCOO-). Such a Sn-MOF electrocatalyst exhibits an outstanding performance with a formate selectivity up to 92% and a current density of 23.2 mA cm-2 at -1.2 VRHE. Density functional theory calculations were used to probe and analyze the catalytic ERCO2 mechanism. This work shows the possibility to achieve a high efficiency of a pure Sn-MOF in catalyzing ERCO2 directly. In addition, this work provides insights into the design and synthesis of highly efficient ERCO2 electrocatalysts for practical applications.

19.
Langmuir ; 38(9): 2852-2861, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35192772

RESUMO

Superhydrophobic surface is an enabling technology in numerous emerging and practical applications such as self-cleaning, anticorrosion, antifouling, anti-icing coatings, and oil-water separation. Here, we report a facile air-assisted electrospray approach to achieve a superhydrophobic surface by systematically studying spray conditions and the chemistry of a coating precursor solution consisting of silicon dioxide nanoparticles, polyacrylonitrile, and N,N-dimethylformamide. The wettability behavior of the surface was analyzed with contact angle measurement and correlated with surface structures. The superhydrophobic coating exhibits remarkable water and oil repellent characteristics, as well as good robustness against abrasion and harsh chemical conditions. This air-assisted electrospray technique has shown great control over the coating process and properties and thus can be potentially used for various advanced industrial applications for self-cleaning and anticorrosion surfaces.

20.
J Colloid Interface Sci ; 612: 235-245, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-34998187

RESUMO

Metal-organic frameworks (MOFs) and their derivatives have shown great potential as electrocatalysts, in virtue of their ease of functionalization and abundance of active sites. Here, we report a series of indium-doped bismuth MOF-derived composites (BiInX-Y@C) for the direct conversion of carbon dioxide (CO2) to hydrocarbon derivatives. Amongst the catalysts studied, BiIn5-500@C demonstrated high selectivity for the production of formate and intrinsic activity in a wide potential window, ranging from - 1.16 to - 0.76 V vs. RHE (VRHE). At - 0.86 VRHE, the Faradaic efficiency and total current density were determined as 97.5% and - 13.5 mA cm-2, respectively. In addition, a 15-h stability test shows no obvious signs of deactivation. Complementary density functional theory (DFT) calculations revealed that the In-doped Bi2O3 are the predominant active centers for HCOOH production in the reduction of CO2 under the action of the BiInX-Y@C catalyst. This work provides new detailed insights into reaction mechanism, and selectivity for reduction of CO2via MOFs, which are expected to inspire and guide the design of novel, selective and efficient catalysts.

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