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1.
Sci Rep ; 14(1): 10935, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740877

RESUMO

Sustainable cellulose-based hydrogels are used in medicine and environmental science. Hydrogels' porosity makes them excellent adsorbents and stable substrates for immobilizing photocatalysts to remove organic dyes. Despite their potential, the implementation of hydrogels for this purpose is still limited due to their high synthesis temperature and low cellulose content. To overcome these challenges, this study develops cellulose-based hydrogels, which have a high cellulose content and can be easily synthesized under ambient conditions. Containing a higher cellulose concentration than previous hydrogels, the synthesized hydrogels are more stable and can be reused numerous times in treatment operations. The hydrogel properties were investigated using Fourier transform infrared spectroscopy, X-ray diffraction and thermal analysis. Scanning electronic microscopy revealed that TiO2 nanoparticles were homogeneously distributed throughout the hydrogel's matrices. In addition, transparent hydrogels allow light to pass through, making them suitable substrates to remove organic dye. The results showed that the hydrogel with TiO2 was able to degrade nearly 90% of organic dye within 180 min. Furthermore, the hydrogel with the embedded catalyst exhibits the potential for reusability with a regeneration efficiency of 80.01% after five runs. These findings suggest that this novel hydrogel is a promising candidate for water pollution remediation.

2.
Bratisl Lek Listy ; 125(6): 392-398, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757598

RESUMO

OBJECTIVES: This study aims to determine the malnutrition status among Vietnamese patients newly diagnosed with gastric cancer (GC). BACKGROUND: GC remains the top rank of common and deadly diseases. With limited clinical manifestation, most GC patients were diagnosed at late stages when tumor is not radically resected. Malnutrition was associated with poor prognosis of GC, such as prolonged hospitalization, limited treatment efficacy and low survival rate. METHODS: The cross-sectional descriptive study recruited 77 patients newly diagnosed with GC and 90 healthy individuals (HC). The data used for this study were approved by the local Ethical Committee. The data were analysed on STATA 14.0 and GraphPad Prism 8.0. RESULTS: We observed the male dominant distribution in GC cohort and over 65% of GC were firstly diagnosed at advanced stages (III and IV). Anemia was detected in about 50% of GC patients. Hyponutrition was prevalent in newly diagnosed GC. We found the decreased tendency of anemia related indexes from HC to early stages (I and II) and advanced stages (III and IV) of GC patients. CONCLUSION: Anemia and hypoproteinemia occurred frequently among Vietnamese newly diagnosed GC. The nutrition therapy would benefit GC patients (Tab. 4, Fig. 4, Ref. 20).


Assuntos
Anemia , Desnutrição , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Vietnã/epidemiologia , Anemia/diagnóstico , Anemia/etiologia , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Idoso , Adulto , Estadiamento de Neoplasias
3.
Nanoscale ; 16(20): 9998-10010, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38699850

RESUMO

Identifying highly stable, cost-effective, platinum-free, and efficient electrocatalysts for the oxygen reduction reaction (ORR) remains a formidable challenge. The ORR is important for advancing fuel cell and zinc-air battery (ZAB) technologies towards cost-efficiency and environmental sustainability. This work presents the utilization of economically viable materials through a straightforward synthesis process, exhibiting the development of efficient Mo2C/Fe3C-NC catalysts ingeniously derived from phosphomolybdic acid (PMA) and iron phthalocyanine (FePc). The results demonstrate that the optimized Mo2C/Fe3C-NC3 catalysts exhibit remarkable electrochemical performance, evidenced by an impressive onset potential of ∼1.0 V versus RHE, a half-wave potential of 0.89 V, and a superior current density of about 6.2 mA cm-2. As for their performance in ZABs, the optimized catalysts reach a peak power density of 142 mW cm-2 at a current density of 200 mA cm-2. This synergy, coupled with the uniform distribution of Mo2C and Fe3C nanoparticles, greatly enhances the active catalytic sites and promotes electrolyte diffusion. Our approach diverges from traditional methods by employing an in situ self-assembled heterostructure of Mo2C/Fe3C on nitrogen-doped carbon tubes, avoiding the conventional high-temperature hydrogen gas reduction process. Beyond serving as feasible alternatives to commercially available Pt/C catalysts, these materials hold promise for large-scale production owing to their affordability and the simplicity of the synthesis technique. Such a breakthrough paves the way towards the realization of sustainable energy technologies and lays the groundwork for further exploration into amplifying the scalability and efficiency of ORR catalysts.

4.
Ann Med ; 56(1): 2354852, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38767238

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a debilitating condition that affects more than 300 million people worldwide. Current treatments are based on a trial-and-error approach, and reliable biomarkers are needed for more informed and personalized treatment solutions. One of the potential biomarkers, gamma-frequency (30-80 Hz) brainwaves, are hypothesized to originate from the excitatory-inhibitory interaction between the pyramidal cells and interneurons. The imbalance between this interaction is described as a crucial pathological mechanism in neuropsychiatric conditions, including MDD, and the modulation of this pathological interaction has been investigated as a potential target. Previous studies attempted to induce gamma activity in the brain using rhythmic light and sound stimuli (GENUS - Gamma Entrainment Using Sensory stimuli) that resulted in neuroprotective effects in Alzheimer's disease (AD) patients and animal models. Here, we investigate the antidepressant, cognitive, and electrophysiological effects of the novel light therapy approach using 40 Hz masked flickering light for patients diagnosed with MDD. METHODS AND DESIGN: Sixty patients with a current diagnosis of a major depressive episode will be enrolled in a randomized, double-blinded, placebo-controlled trial. The active treatment group will receive 40 Hz masked flickering light stimulation while the control group will receive continuous light matched in color temperature and brightness. Patients in both groups will get daily light treatment in their own homes and will attend four follow-up visits to assess the symptoms of depression, including depression severity measured by Hamilton Depression Rating Scale (HAM-D17), cognitive function, quality of life and sleep, and electroencephalographic changes. The primary endpoint is the mean change from baseline to week 6 in depression severity (HAM-D6 subscale) between the groups.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/terapia , Método Duplo-Cego , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Fototerapia/métodos , Resultado do Tratamento , Adulto Jovem , Ritmo Gama/fisiologia , Idoso , Eletroencefalografia/métodos , Adolescente
5.
J Am Heart Assoc ; 13(9): e033078, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38639361

RESUMO

BACKGROUND: This review aimed to quantify the impact of socioeconomic status on functional outcomes from stroke and identify the socioeconomic status indicators that exhibit the highest magnitude of association. METHODS AND RESULTS: We performed a systematic literature search across Medline and Embase from inception to May 2022, to identify observational studies (n≥100, and in English). Risk of bias was assessed using the modified Newcastle Ottawa Scale. Random effects meta-analysis was used to pool data. We included 19 studies (157 715 patients, 47.7% women) reporting functional outcomes measured with modified Rankin Scale or Barthel index, with 10 assessed as low risk of bias. Measures of socioeconomic status reported were education (11 studies), income (8), occupation (4), health insurance status (3), and neighborhood socioeconomic deprivation (3). Pooled data suggested that low socioeconomic status was significantly associated with poor functional outcomes, including incomplete education or below high school level versus high school attainment and above (odds ratio [OR], 1.66 [95% CI, 1.40-1.95]), lowest income versus highest income (OR, 1.36 [95% CI, 1.02-1.83]), a manual job/being unemployed versus a nonmanual job/working (OR, 1.62 [95% CI, 1.29-2.02]), and living in the most disadvantaged socioeconomic neighborhood versus the least disadvantaged (OR, 1.55 [95% CI, 1.25-1.92]). Low health insurance status was also associated with an increased risk of poor functional outcomes (OR, 1.32 [95% CI, 0.95-1.84]), although this was association was not statistically significant. CONCLUSIONS: Despite great strides in stroke treatment in the past decades, social disadvantage remains a risk factor for poor functional outcome after an acute stroke. Further research is needed to better understand causal mechanisms and disparities.


Assuntos
Classe Social , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/epidemiologia , Recuperação de Função Fisiológica , Renda , Determinantes Sociais da Saúde , Escolaridade , Fatores de Risco , Estado Funcional , Reabilitação do Acidente Vascular Cerebral , Fatores Socioeconômicos , Feminino , Masculino
6.
Cureus ; 16(3): e56246, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38623111

RESUMO

A large portion of the world's population is affected by acne vulgaris (AV), with many of these individuals being adolescents. The underlying mechanism of AV is hyperkeratinization and Cutibacterium acnes infection of the pilosebaceous follicle secondary to excessive stimulation of sebaceous glands by androgens. Metformin is a biguanide medication primarily used in efforts to lower patients' sugar levels in the management of type 2 diabetes. It has been proven to reduce levels of circulating androgens in patients with insulin resistance, indicating its potential for treating AV. A search strategy was developed and performed using the databases Ovid Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica database (EMBASE), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Controlled Register of Trials (CENTRAL), and Web of Science. The keywords "metformin" and "acne" were searched, along with related Medical Subject Headings (MeSH) and other subject headings. Studies that met the inclusion criteria were controlled trials, published after 2010, and in the English language. Participants with and without comorbidities such as polycystic ovary syndrome (PCOS) were considered. Two independent reviewers screened studies based on predefined criteria and extracted data from each study, which were quantitatively combined. A total of 15 studies were included in this systematic review. Across the 15 studies, there were 1,046 participants, with 13 studies looking exclusively at women with PCOS. Of the remaining two studies, one examined males with altered metabolic profiles, while the other included men and women with moderate AV. Notable risks of bias included studies that did not exclusively state the blindness of the study. Of the studies that were examined, 13 showed that metformin reduces AV, with seven studies showing statistical significance. Acne vulgaris is an inflammatory condition that has plagued patients for years due to the limited treatment options available. The hyperglycemic medication metformin, used in the management of type 2 diabetes, is being explored as a novel therapeutic that can possibly be repurposed for the treatment of AV. The use of metformin in AV is hypothesized to disrupt the proposed linkage between insulin resistance and AV proliferation. This proposed research could offer physicians a new option for the treatment of AV as well as render an alternative AV treatment for patients.

7.
Dalton Trans ; 53(16): 7213-7228, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38584502

RESUMO

While metal-organic framework (MOF) photocatalysts have demonstrated a unique Cr(VI) photoreduction capability in recent decades, their performance is still insufficient for practical applications because of their low Cr(VI) uptake and poor visible light response. To cope with these drawbacks, a new OH-modified Zr-based MOF, termed HCMUE-1, was successfully prepared via a solvothermal method in this work. The complete characterization of HCMUE-1 was performed through various techniques, including powder X-ray diffraction (PXRD), Raman spectroscopy, Fourier transform infrared (FT-IR), thermogravimetric analysis and differential scanning calorimetry (TGA-DSC), scanning electron microscopy combined with energy-dispersive X-ray (SEM-EDX), and X-ray photoelectron spectroscopy (XPS). The obtained data exhibited the excellent Cr(VI) photoreduction efficiency of HCMUE-1, reaching up to 98% after 90 min and almost 100% after 120 min under visible light illumination in a low acidic medium. Noteworthily, HCMUE-1 retained the same Cr(VI) removal rate for at least seven cycles without considerable loss. Further experimental investigations demonstrated that the structural stability and surface morphology of HCMUE-1 were retained after photoreduction. Moreover, the photocatalytic reduction mechanism of Cr(VI) to Cr(III) was interpreted through a series of systematic experimental measurements. These results indicate that HCMUE-1 possesses potential as an efficient photocatalyst for reducing toxic Cr(VI) species from wastewater in real-life conditions.

8.
Foot Ankle Orthop ; 9(2): 24730114241247826, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38659719

RESUMO

Background: Ankle fractures are a common injury treated by orthopaedic surgeons. Unstable, displaced ankle fractures are often fixed with open reduction internal fixation (ORIF) using different implant constructs at various cost. No study to date has looked at transparency in ankle implant costs to surgeon behavior. Our surgeons self-identified that the biggest barrier for lowering implant cost was the lack of cost transparency. This was a surgeon-led-study to evaluate whether increased transparency in implant costs affected surgeon behavior. Methods: Monthly operative logs from December 2021 to September 2022 were reviewed at our level 1 trauma center for operative fixation of ankle fractures. The cost data of each fixation construct was reported to trauma-trained surgeons at the end of each month from March 2022 to June 2022. Average costs of implants were compared before and after education. A linear mixed model was used to explore what factors were associated with changes in costs. Surgeons also participated in a poststudy survey. Results: The implant costs of 110 ankle fracture fixations were reviewed over the period before education (n = 60), during education (n = 30), and after education (n = 20). The mean implant cost difference for unimalleolar fractures was -$204.80 (P = .68), whereas the mean cost difference for bimalleolar fractures was -$9.82 (P = .98). Trimalleolar fractures had a mean cost difference of +$94.47 (P = .84). Linear mixed model demonstrated fracture pattern as the only factor significantly associated with implant costs (P < .01). Post-education surgeon survey revealed that 6 of 7 surgeons felt that monthly updates affected their implant selection. However, only 2 surgeons demonstrated a change in practice with decreased implant costs during the study. Conclusion: The majority of surgeons self-reported being influenced by the implant cost education, but the detected change in implant cost was only observed in less than one-third of surgeons. Our results suggest implant selection and related costs are not influenced by increased cost transparency education alone. Level of Evidence: Level III, case control study.

9.
ACS Omega ; 9(15): 16949-16958, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38645317

RESUMO

Three-dimensional (3D) cell culture systems are becoming increasingly popular due to their ability to mimic the complex process of angiogenesis in cancer, providing more accurate and physiologically relevant data than traditional two-dimensional (2D) cell culture systems. Microwell systems are particularly useful in this context as they provide a microenvironment that more closely resembles the in vivo environment than traditional microwells. Poly(ethylene glycol) (PEG) microwells are particularly advantageous due to their bio-inertness and the ability to tailor their material characteristics depending on the PEG molecular weight. Although there are several methods available for microwell fabrication, most of them are time-consuming and expensive. The current study utilizes a low-cost laser etching technique on poly(methyl methacrylate) materials followed by molding with PDMS to produce microwells. The optimal conditions for making concave microwells are an engraving parameter speed of 600 mm/s, power of 20%, and a design diameter of the microwell of 0.4 mm. The artificial tumor achieved its full size after 7 days of cell growth in a microwell system, and the cells developed drugs through a live/dead assay test. The results of the drug testing revealed that the IC50 value of zerumbone-loaded liposomes in HepG2 was 4.53 pM, which is greater than the IC50 value of zerumbone. The HepG2 cancer sphere's 3D platform for medication testing revealed that zerumbone-loaded liposomes were very effective at high doses. These findings generally imply that zerumbone-loaded liposomes have the capacity to target the liver and maintain medication delivery.

10.
Sex Med Rev ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38686687

RESUMO

INTRODUCTION: The prevalence of male sexual dysfunction (MSD) increases with age, with >50% of men aged >40 years reporting erectile dysfunction (ED). In recent years, wearable male sex devices (WMSDs) have been increasingly utilized by patients and recommended by sexual medicine clinicians. OBJECTIVES: This study seeks to investigate the safety and efficacy of products currently marketed for the treatment of MSD. METHODS: Available products for WMSDs were reviewed by analyzing product websites, forums, advertisements, and clinical recommendations. Qualitative comparisons were based on patient reviews, cost, and specific features. Investigatory evidence and Food and Drug Administration status were also reviewed. Additionally, Google Trends was used to determine the popularity of devices over time. RESULTS: Eight WMSDs for the treatment of MSD and enhancement of sexual pleasure were reviewed. Constriction bands, such as the Maintain Ring Loop, Eddie by Giddy, and Xialla, have shown significant benefits in clinical trials and were the most popular devices among patients. Smart devices can provide real-time feedback on erectile quality and/or sexual performance. Similar to the RigiScan, the Adam sensor provides feedback on erectile quality while monitoring changes in penile tumescence during sleep with additional analysis available through a mobile application. Neuromodulation devices such as the Morari Patch and vPatch/in2 Patch use electrical stimulation to delay ejaculation and improve sexual function. The FirmTech Performance Ring uses sensors to track the vital signs of erectile fitness with clinical trials ongoing. CONCLUSIONS: Overall, this review describes the available investigatory evidence for a range of WMSDs and highlights the potential benefits and limitations of these devices in treating MSD and enhancing sexual pleasure. Further research is needed to evaluate the effectiveness of these devices and to determine which ones may be the most suitable for individual patients.

11.
Nanoscale Adv ; 6(7): 1822-1836, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38545284

RESUMO

This paper is devoted to reviewing a decade of the development of vacuum sputter deposition onto liquid poly(ethylene glycol) (PEG) to prepare metal and alloy nanoparticles (NPs) with a controlled particle growth, size, structure, and composition. Especially, we have discussed the fine structures of alloy NPs obtained in PEG and compared them with those sputtered onto other non-volatile liquids. Finally, we have shared our prospect of applications for the resulting alloy NPs.

12.
RSC Med Chem ; 15(3): 1046-1054, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516598

RESUMO

Plants of the Zingiberaceae family, specifically those belonging to the Curcuma species, are commonly under consideration as potential therapeutic agents for the management of gastrointestinal diseases. In this study, we carried out a phytochemical study on Curcuma aromatica Salisb. (or so-called "Nghe trang" in Vietnamese) grown in Vietnam, which yields three newly discovered 3,5-diacetoxy diarylheptanoids (1-3) and six known 3,5-dihydroxyl diarylheptanoids (4-9). The bioactivity assessment shows that all isolated compounds, except compounds 3, 7, and 8, could inhibit urease. Compounds 4 and 9 significantly inhibit urease, with an IC50 value of 9.6 and 21.4 µM, respectively, more substantial than the positive control, hydroxyurea (IC50 = 77.4 µM). The structure-activity relationship (SAR) of linear diarylheptanoids was also established, suggesting that the hydroxyl groups at any position of skeleton diarylheptanoids are essential for exerting anti-urease action. Through a comparative analysis of the binding sites of hydroxyurea and diarylheptanoid compounds via our constructed in silico model, the mechanism of action of diarylheptanoid compounds is predicted to bind to the dynamic region close to the dinickel active center, resulting in a loss of catalytic activity. Such insights certainly help design and/or find diarylheptanoid-based compounds for treating gastric ulcers through inhibiting urease.

13.
J Pediatr Gastroenterol Nutr ; 78(4): 927-935, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38451048

RESUMO

OBJECTIVES: Nuts are nutrient-dense foods rich in unsaturated fatty acids, protein, dietary fiber, vitamins, and minerals. The present prebirth cohort study examined the association between maternal nut intake during pregnancy and the risk of childhood behavioral problems in 5-year-old Japanese children. METHODS: Study subjects were 1199 mother-child pairs. Dietary intake was assessed using a diet history questionnaire. Emotional problems, conduct problems, hyperactivity problems, peer problems, and low prosocial behavior were assessed using the parent-reported version of the Strengths and Difficulties Questionnaire. Adjustments were made for a priori-selected nondietary confounders and potentially related dietary factors. RESULTS: Compared with mothers who had not eaten nuts during pregnancy, mothers who had eaten nuts had a significantly reduced risk of peer problems in children; the adjusted odds ratio was 0.64 (95% confidence interval: 0.42-0.97). There were no measurable associations between maternal consumption of nuts during pregnancy and the risk of childhood emotional problems, conduct problems, hyperactivity problems, and low prosocial behavior. CONCLUSIONS: Maternal consumption of nuts during pregnancy may be associated with a decreased risk of peer problems in 5-year-old children.


Assuntos
Nozes , Comportamento Problema , Feminino , Gravidez , Humanos , Pré-Escolar , Estudos de Coortes , Japão , Mães
15.
JBJS Case Connect ; 14(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38452162

RESUMO

CASE: We present the case of a 25-year-old man with body mass index of 77 who underwent open reduction internal fixation (ORIF) of a displaced fracture dislocation of the acetabulum after a high-speed motor vehicle accident. Remarkably, he achieved full weight-bearing with minimal hip pain and has returned to independent mobility and meaningful work. CONCLUSION: ORIF of an acetabular fracture in a patient with class III obesity presents many challenges. Positioning, surgical approach, fracture manipulation, and postoperative morbidity and mortality can be managed through interdisciplinary collaboration and preoperative communication.


Assuntos
Artroplastia de Quadril , Fraturas do Quadril , Masculino , Humanos , Adulto , Acetábulo/cirurgia , Índice de Massa Corporal , Fixação Interna de Fraturas , Seguimentos , Fraturas do Quadril/cirurgia
16.
J Orthop ; 53: 114-117, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38495580

RESUMO

Introduction: With the increasing incidence of total knee arthroplasty (TKA), there is an expected rise in rate of periprosthetic fractures in the coming years. It is unclear how the outcomes of patients with distal femur fractures (DFF) and a total knee arthroplasty compare to patients of the same age group with native knees (NK). Materials and methods: A retrospective review was completed for distal femur fractures treated with surgical fixation from January 2019-March 2021. We excluded patients <50 years old, non-ambulatory patients, revision surgeries, and patients with less than 90 days of follow-up. A chart review was performed to collect age, gender, BMI, smoking status, American Society of Anesthesiology (ASA) classification, fracture type, fixation method, time to full weight bearing, and complications. Comparisons between the TKA vs native knee groups were performed using t-test, chi-square, and Fisher's exact test where appropriate. Results: 138 patients were included in our study with a mean age of 74 years. 69 DFF ipsilateral to a TKA were included in the study group and 71 DFF were included in the native knee group. Age, sex, BMI, smoking status, and ASA class were similar between the groups. All patients with periprosthetic femur fractures had 33A AO/OTA fracture classification. Patients with native knees were more likely to receive dual implant fixation, 15.5% compared to 4.3% (p = 0.02). Full weight bearing was achieved at 8.5 vs 8.6 weeks between the NK and TKA groups (p = 0.64). The complication rate was 16.9% in the NK group vs. 7.2% in the TKA group (p = 0.21). Conclusion: Patients with periprosthetic femur fractures have similar time to weight bearing and complications rate with patients with distal femur fracture in native knees. We found a higher utilization rate of dual implant fixation in the native knee group.

17.
Small ; : e2400779, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546187

RESUMO

The development of an efficient electrocatalyst for HMF oxidation to FDCA has been in the early stages. Herein, the NiNPs/GO-Ni-foam is fabricated as an electrocatalyst for FDCA production. However, the electrocatalytic performance of the untreated NiNPs/GO-Ni-foam is observed with moderate Faradaic efficiency (FE) (73.0%) and FDCA yield (80.2%). By electrochemically treating the NiNPs/GO-Ni-foam in an alkaline solution with positive potential at different treatment durations, the degree of NiOOH on metal surfaces is changed. The distinctive electrocatalytic activity obtained when using the different NiOOH degrees allows to understand the crucial impact of NiOOH species in HMF electrooxidation. Enhancing the portion of the NiOOH phase on the electrocatalyst surface improves electrocatalytic activity in terms of FE and FDCA yield up to 94.8±4.8% and 86.9±4.1%, respectively. Interestingly, as long as the NiOOH portion on the electrocatalyst surface is preserved or regenerated, the electrocatalyst performance can be intact even after several catalytic cycles. The theoretical study via density functional theory (DFT) also agrees with the experimental observations and confirms that the NiOOH phase facilitates the electrochemical transformation of HMF to FDCA through the HMFCA pathway, and the potential limiting step of the overall reaction is the oxidation of FFCA to FDCA.

18.
Luminescence ; 39(3): e4698, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38462505

RESUMO

In this study, cerium ion (Ce3+ )-doped calcium scandium silicate garnet (Ca3 Sc2 Si3 O12 , abbreviated CSSG) phosphors were successfully synthesized using the sol-gel method. The crystal phase, morphology, and photoluminescence properties of the synthesized phosphors were thoroughly investigated. Under excitation by a blue light-emitting diode (LED) chip (450 nm), the CSSG phosphor displayed a wide emission spectrum spanning from green to yellow. Remarkably, the material exhibited exceptional thermal stability, with an emissivity ratio at 150°C to that at 25°C reaching approximately 85%. Additionally, the material showcased impressive optical performance when tested with a blue LED chip, including a color rendering index (CRI) exceeding 90, an R9 value surpassing 50, and a biological impact ratio (M/P) above 0.6. These noteworthy findings underscore the potential applications of CSSG as a white light-converting phosphor, particularly in the realm of human-centered lighting.


Assuntos
Cério , Iluminação , Humanos , Luz , Silicatos/química , Cálcio , Cério/química
19.
Adv Mater ; : e2312508, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38465829

RESUMO

Sodium foil, promising for high-energy-density batteries, faces reversibility challenges due to its inherent reactivity and unstable solid electrolyte interphase (SEI) layer. In this study, a stable sodium metal battery (SMB) is achieved by tuning the electrolyte solvation structure through the addition of co-solvent 2-methyl tetrahydrofuran (MTHF) to diglyme (Dig). The introduction of cyclic ether-based MTHF results in increased anion incorporation in the solvation structure, even at lower salt concentrations. Specifically, the anion stabilization capabilities of the environmentally sustainable MTHF co-solvent lead to a contact-ion pair-based solvation structure. Time-of-flight mass spectroscopy analysis reveals that a shift toward an anion-dominated solvation structure promotes the formation of a thin and uniform SEI layer. Consequently, employing a NaPF6-based electrolyte with a Dig:MTHF ratio of 50% (v/v) binary solvent yields an average Coulombic efficiency of 99.72% for 300 cycles in Cu||Na cell cycling. Remarkably, at a C/2 cycling rate, Na||Na symmetric cell cycling demonstrates ultra-long-term stability exceeding 7000 h, and full cells with Na0.44MnO2 as a cathode retain 80% of their capacity after 500 cycles. This study systematically examines solvation structure, SEI layer composition, and electrochemical cycling, emphasizing the significance of MTHF-based binary solvent mixtures for high-performance SMBs.

20.
ACS Appl Mater Interfaces ; 16(9): 11537-11551, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38361372

RESUMO

The strategy of defect engineering is increasingly recognized for its pivotal role in modulating the electronic structure, thereby significantly improving the electrocatalytic performance of materials. In this study, we present defect-enriched nickel and iron oxides as highly active and cost-effective electrocatalysts, denoted as Ni0.6Fe2.4O4@NC, derived from NiFe-based metal-organic frameworks (MOFs) for oxygen reduction reactions (ORR) and oxygen evolution reactions (OER). XANES and EXAFS confirm that the crystals have a distorted structure and metal vacancies. The cation defect-rich Ni0.6Fe2.4O4@NC electrocatalyst exhibits exceptional ORR and OER activities (ΔE = 0.68 V). Mechanistic pathways of electrochemical reactions are studied by DFT calculations. Furthermore, a rechargeable zinc-air battery (RZAB) using the Ni0.6Fe2.4O4@NC catalyst demonstrates a peak power density of 187 mW cm-2 and remarkable long-term cycling stability. The flexible solid-state ZAB using the Ni0.6Fe2.4O4@NC catalyst exhibits a power density of 66 mW cm-2. The proposed structural design strategy allows for the rational design of electronic delocalization of cation defect-rich NiFe spinel ferrite attached to ultrathin N-doped graphitic carbon sheets in order to enhance active site availability and facilitate mass and electron transport.

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