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BACKGROUND: We aimed to investigate the clinical and angiographic characteristics of patients with acute coronary syndrome (ACS) who survived this devastating earthquake and were admitted to our hospital in Antakya/Türkiye. METHODS: We retrospectively examined the impact of the earthquake on the occurrences of acute coronary syndromes in Antakya/Türkiye. All 248 consecutive patients with ACS, also survivors of the earthquake in Antakya, were enrolled as the earthquake group. The earthquake group was created from patients hospitalized between February and June in 2023 after the earthquake. In total, 209 consecutive ACS patients who were hospitalized in our cardiology clinic in similar months of 2022 named as the control group. RESULTS: Patients admitted before the earthquake were more hospitalized with multivessel disease compared to after the earthquake group (P <.001). Myocardial infarction with non-obstructive coronary artery disease (MINOCA) was the main reason for the significant increase rate of ACS after the earthquake. The earthquake patient group had lesser diabetes mellitus than the control group (P <.001). The risk of men suffering from ACS after an earthquake is approximately 2.1 times higher than women (P =.023). Those with a history of revascularization are approximately 1.8 times more likely to have ACS after an earthquake (P =.05). The risk of experiencing ACS after an earthquake is approximately 3.5 times higher for those with a family history than for those without (P <.001). CONCLUSION: Effects of the devastating earthquake on the heart are the increase in MINOCA patients triggered by great sudden environmental stress and the decrease in diabetes due to worsening nutritional conditions, respectively.
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BACKGROUND: The effects of thyroid hormone on patients hospitalized in coronary intensive care units are still controversial. Objective: We retrospectively examined thyroid hormone levels and their impact on cardiovascular morbidity in patients admitted to coronary intensive care units. METHODS: A total of 208 (Female/Male; 46.6%/53.4%) patients without any history of thyroid disease were enrolled and screened. Patients with specific heart disease and existing thyroid hormone parameters were included in the study. Low triiodothyronine syndrome is characterized by reduced serum total or free T3 (fT3) concentrations in normal free T4 (fT4) and TSH levels. RESULTS: The common diagnosis of the patients in the coronary care unit is acute coronary syndrome (n=59, 28.2 %) and heart failure (n=46, 23.3%). Patients were divided into two groups according to left ventricular ejection fraction percentages (LVEF ≤39% vs LVEF ≥40%). Plasma fT3 levels were significantly correlated with low LVEF (≤39%) (p =0.002). fT3 (r=-0.183, p =0.013) and hospitalization etiology (r=-0.161, p =0.023) were also the most critical parameters affecting the length of hospitalization. CONCLUSION: Low fT3 was associated with reduced ejection fraction and prolonged hospitalization, which may lead to potential morbidities in HF patients and may be useful in risk stratification and treatment strategies.
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In this study, glucose was used as the carbon source to synthesize carbon quantum dots (CQDs) and also aimed to synthesize CQDs doped with heteroatoms such as sulphur, nitrogen, and boron to enhance their functionality. The obtained material has been characterized by several techniques. According to FL analysis, the highest peaks for CQD, N-CQD, B-CQD, and S-CQD were determined as 432 nm (ex 350), 425 (ex 350), 430 nm (ex 340 nm), and 436 nm (ex 340 nm), respectively. FTIR spectra showed different characteristic peaks for CQD, and the FTIR results show that CQDs have a unique structure. According to TEM analysis, the morphology of all CQDs was found to be spherical and monodisperse with average sizes in the range of 5-7 nm. The characterization results of CQDs show that the addition of heteroatoms changes the properties of CQDs. The synthesized CQDs were also tested as colorimetric sensors for the detection of heavy metals. It was observed that CQDs detected Fe3+ metal ions, B-CQD and S-CQD detected Fe3+ and Ag+ metal ions, and N-CQDs detected Ca2+ metal ions. Sensor studies were performed for all CQDs and linear plots were obtained against metal concentrations in the range of 0.06-1.23 µM. LOD values for CQD, N-CQD, S-CQD, and B-CQD were calculated as 0.187 µM (Fe3+), 0.391 µM (Ca2+), 0.224 µM (Fe3+)-0.442 µM (Ag+), and 0.182 µM (Fe3+)-0.174 µM (Ag+), respectively. The results show that the addition of B, N, and S atoms to CQDs plays a role in the improvement and modification of colorimetric sensor properties and has the potential to be used in sensor applications for the detection of heavy metals in areas such as the environment and health.
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The BaBiO3 (BBO) perovskite oxide was prepared via a sol-gel method with different concentrations of Bi nitrate and examined as a photocatalyst for RhB degradation under sunlight, and its antioxidant and antibacterial activities were examined. X-ray diffraction (XRD) indicated the formation of a BaBiO3-BaCO3 (BBO-BCO) binary composite. For the degradation of RhB under solar radiation, high photocatalytic activity (73%) was observed. According to the antibacterial activity study, the addition of Bi enhanced the antibacterial activity of the resulting material against both Gram-positive and Gram-negative microorganisms. The Bi%-BBO (Bi 20%) inhibited 96.23% S. aureus. 10% Bi-BBO as an antioxidant agent had the most efficacious IC50 value of 2.50 mg mL-1. These results seem to suggest that BBO-BCO is a promising catalytic material with potential application in the fields of catalysis and medicine.
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This study investigates the temperature-dependent frictional behavior of MoS2 in humid environments within the context of a long-standing debate over increased friction due to oxidation processes or molecular adsorption. By combining sliding friction experiments and density functional theory (DFT)-based first-principles simulations, it aims to clarify the role of water molecule adsorption in influencing frictional properties of MoS2, addressing the challenge of identifying interfacial bonding behavior responsible for friction in such conditions. Sliding experiments revealed that magnetron-sputtered MoS2 exhibits a reduction in the coefficient of friction (COF) with an increase in temperature from 25 to 100 °C under 20 and 40% relative humidity. This change in the COF obeys the Arrhenius law, presenting an energy barrier of 0.165 eV, indicative of the temperature-dependent nature of these frictional changes and suggests a consistent frictional mechanism. DFT simulations showed that H2O molecules are adsorbed at MoS2 vacancy defects with adsorption energies ranging from -0.56 to -0.17 eV, which align with the experimentally determined energy barrier. Adsorptive interactions, particularly the formation of stable H···S interfacial hydrogen bonds at defect sites, increase the interlayer adhesion and impede layer shearing. TEM analysis confirms that although MoS2 layers align parallel to the sliding direction in humid conditions, the COF remains at 0.12, as opposed to approximately 0.02 in dry air. This demonstrates that parallel layer alignment does not notably decrease the COF, underscoring humidity's significant role in MoS2's COF values, a result also supported by the Arrhenius analysis. The reversibility of the physisorption process, demonstrated by the recovery of the COF in high-temperature humid environments, suggests its dynamic nature. This study yields fundamental insights into MoS2 interfaces for environments with variable humidity and temperature, crucial for demanding tribological applications.
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Carvedilol can inhibit inflammation, vasoconstriction, and oxidative stress, which play important roles in the development and progression of contrast-induced nephropathy (CIN). To the best of our knowledge, no studies have investigated the potential effect of carvedilol on the prevalence of CIN after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). The present study aimed to determine whether carvedilol use is associated with the development of CIN. A total of 319 patients (mean age, 59.2 ± 12.4 years; 77.7% male) with ACS who underwent urgent PCI at our institution between May 2019 and May 2022 were included prospectively. Overall, 100 and 219 patients were assigned to the carvedilol and metoprolol groups, respectively. The prevalence of CIN was significantly lower in the carvedilol group (6.0%) than in the metoprolol group (18.3%; P = .003). Multivariate analysis revealed that carvedilol use (odds ratio [OR] .250, 95% confidence interval [CI] .092-.677, P = .006), amount of contrast agent (OR 1.004, 95% CI 1.000-1.008, P = .031), and admission estimated glomerular filtration rate (OR .978, 95% CI 0.960-.995, P = .014) were independently associated with the development of CIN. The use of carvedilol may be a promising option for the prevention of CIN in patients with ACS undergoing urgent PCI.
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Síndrome Coronario Agudo , Enfermedades Renales , Intervención Coronaria Percutánea , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Síndrome Coronario Agudo/diagnóstico por imagen , Síndrome Coronario Agudo/cirugía , Carvedilol/uso terapéutico , Metoprolol/uso terapéutico , Intervención Coronaria Percutánea/efectos adversos , Medios de Contraste/efectos adversos , Enfermedades Renales/inducido químicamente , Angiografía Coronaria/efectos adversos , Factores de RiesgoRESUMEN
Immune-inflammatory biomarkers have been shown to be correlated with impaired coronary flow (ICF) in ST-segment elevation myocardial infarction. In this study, we assessed the relation between a novel comprehensive biomarker, pan-immune-inflammation value (PIV), and ICF after primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction. A total of 687 patients who underwent pPCI between 2019 and 2023 were retrospectively analyzed. Blood samples were collected at admission. PIV and other inflammation parameters were compared. PIV was calculated as (neutrophil count × platelet count × monocyte count)/lymphocyte count. Postprocedural coronary flow was assessed by thrombolysis in myocardial infarction (TIMI) classification. Patients were divided into 2 groups: a group with ICF defined as postprocedural TIMI 0 to 2 and a group with normal coronary flow defined as postprocedural TIMI flow grade of 3. The mean age was 61 ± 12 years, and 22.4% of the patients were women. Compared with the normal coronary flow group (median 492, interquartile range 275 to 931), the ICF group (median 1,540, interquartile range 834 to 2,909) showed significantly increased PIV (p <0.001). The optimal cutoff for the PIV was 804, as determined by receiver operating characteristic curve. The incidence of ICF was 17.0% in all patients, 6.4% in low-PIV group (<804), and 34.2% in high-PIV group (≥804). Multivariate analyses revealed that a baseline PIV ≥804 was independently associated with post-pPCI ICF (odds ratio 5.226, p <0.001). PIV was superior to neutrophil/lymphocyte ratio and platelet/lymphocyte ratio in determining ICF. In conclusion, a high-PIV was significantly associated with an increased risk of ICF after pPCI. Moreover, PIV was a better indicator of ICF than were other inflammatory markers.
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Infarto del Miocardio , Fenómeno de no Reflujo , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Estudios Retrospectivos , Fenómeno de no Reflujo/etiología , Infarto del Miocardio con Elevación del ST/complicaciones , Infarto del Miocardio/complicaciones , Biomarcadores , Inflamación/etiología , Intervención Coronaria Percutánea/efectos adversos , Angiografía Coronaria/efectos adversos , Resultado del TratamientoRESUMEN
Semiconducting single-walled carbon nanotubes (s-SWCNT) are structures that fluoresce in the near-infrared region. By coating SWCNT surfaces with polymeric materials such as single-chain DNA, changes in fluorescence emission occur in the presence of reagents. In this way, polymer-coated SWCNT structures allow them to be used as optical sensors for single molecule detection. Especially today, the inadequacy of the methods used in the detection of cellular molecules makes the early diagnosis of diseases such as cancer difficult at the single-molecule level. In this study, the detection of nitric oxide (NO) signals, which are a marker of cancer, was carried out at the single-molecule level. In this context, a sensor structure was formed by coating the 7,6-chiral s-SWCNT surface with ssDNA with different oligonucleotide lengths (AT). The sensor structure was characterized by using UV-vis spectroscopy and Raman spectroscopy microscopy. After formation of the sensor structure, a selectivity library was created using various molecules. As a result of the coating of the SWCNT (7,6) surface with DNA corona phase formation, Raman peaks at 195 and 276 cm-1 were observed to shift to the right. Additionally, the selectivity library results showed that the (AT)30 sequence can be used in NO detection. As a result of the studies using SWCNT (7.6)- (AT)30, the limit of detection (LOD) and limit of determination (LOQ) values of the sensor against NO were found to be 1.24 and 4.13 µM, respectively.
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Nanotubos de Carbono , Neoplasias , Humanos , Óxido Nítrico , Nanotubos de Carbono/química , ADN/química , PolímerosRESUMEN
Background: Chronic coronary syndrome (CCS) is one of the most life-restricting coronary artery diseases, and symptom relief is the main goal in CCS patients who suffer from angina. Objectives: To assess the potential benefits of device-guided breathing in CCS patients with angina in this randomized, controlled, single-blinded study. Methods: Fifty-one patients with CCS received device-guided breathing for 7 days/8 weeks. Exercise capacity [exercise stress test], cardiac function [transthoracic echocardiography], and angina severity [Canadian Cardiovascular Society Classification] were evaluated initially and after the training. Device-guided breathing was performed at the lowest resistance of the device (POWERbreathe® Classic LR) for the control group (n = 17). The low load training group (LLTG; n = 18) and high load training group (HLTG; n = 16) were trained at 30% and 50% of maximal inspiratory pressure. Baseline characteristics were compared using one-way ANOVA and Kruskal-Wallis test. Categorical data were compared using the chi-square test. ANCOVA was performed to compare changes between three groups. A p value < 0.05 was considered statistically significant. Results: Metabolic equivalent values were significantly improved in both HLTG and LLTG groups (p < 0.001, p = 0.003). The Duke treadmill score significantly improved and shifted to low-risk both in the HLTG (p < 0.001) and LLTG (p < 0.001) groups. Angina severity significantly alleviated after the training in both HLTG and LLTG groups (p < 0.001, p = 0.002). Conclusions: An 8-week long program of short-term respiratory muscle training provided positive gains in exercise capacity and angina severity in CCS patients with angina. The effects of long-term training programs on CCS patients should be investigated clinically because of the possibility of helping to decrease the need for invasive treatments.
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Hydrogen peroxide (H2O2) and heavy metals, which are among the wastes of the industrial sector, become a threat to living things and the environment above certain concentrations. Therefore, the detection of both H2O2 and heavy metals with simple, low-cost, and fast analytical methods has gained great importance. The use of nanoparticles in colorimetric sensor technology for the detection of these analytes provides great advantages. In recent years, green synthesis of nanomaterials with products that can be considered biowaste is among the popular topics. In this study, silver/silver chloride nanoparticles (Ag@AgCl NPs) were synthesized using the green synthesis method as an eco-friendly and cheap method, the green algae extract was used as a reducing agent. The characterization of Ag@AgCl nanoparticles and green algae extract was carried out with several techniques such as Transmission Electron Microscopy (TEM), UV-Visible spectrometry (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction patterns (XRD) methods were used for characterization. According to TEM analysis, the Ag@AgCl NPs typically spherical in form and range in size from 4 to 10 nm, and UV-vis showed the formation of surface plasmon resonance (SPR) of the Ag@AgCl between 400 and 450 nm. In addition, its activity as a colorimetric sensor for hydrogen peroxide (H2O2) and multi-metal detection was evaluated. Interestingly, Ag/AgCl NPs caused different color formations for 3 metals simultaneously in the sensor study for heavy metal detection, and Fe3+, Cu2+, and Cr6+ ions were detected. The R2 values for H2O2, Fe3+, Cu2+, and Cr6+ were 0.9360, 0.9961, 0.9787, and 0.9625 the limit of detection (LOD) was 43.75, 1.69, 3.18, and 5.05 ppb (ng/mL), respectively. It was determined that Ag@AgCl NPs have the potential to be used as a colorimetric sensor for the detection of H2O2 and heavy metals from wastewater.
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Nanopartículas del Metal , Nanoestructuras , Colorimetría/métodos , Peróxido de Hidrógeno/análisis , Plata/química , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas del Metal/química , Difracción de Rayos XRESUMEN
In this work, for the removal of azo dyes that cause environmental pollution, TiO2-ZnO has been modified with graphitic carbon nitride (g-C3N4) to form an advanced hetero-linked photocatalyst. With this catalyst, photocatalytic hydrogen production and photodegradation activity against methylene orange (MO) and rhodamineB (RhB) dye removal were studied. The synthesized nanostructure was extensively characterized by several techniques such as XRD, TEM, UV-Vis and fluorescence spectrophotometer (PL) techniques. According to the analysis, a significant increase in the photocatalytic efficiency of TiO2-ZnO was determined after it was modified with g-C3N4 nanostructures. The combination between TiO2-ZnO and g-C3N4 was shown to be responsible for the improvement in photocatalytic activity because it significantly decreased electron-hole recombination. After 90 min the 62.81% of MO dye was removed but at 120 min only 57% of RhB was degraded. In addition, the antibacterial activity of TiO2-ZnO/g-C3N4 catalyst was carried out against gram positive and gram negatif bacteria. The bacterial inhibition (%) of TiO2-ZnO/g-C3N4 catalyst.was found to be 44 % against E. coli and 33 % against at 100 µg/ml concentration. In line with the analyzes obtained with this study, important results have been revealed for the application of photocatalytic methods in more industrial dimensions in the production of hydrogen, which is a valuable energy type.
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Nanocompuestos , Óxido de Zinc , Agua , Colorantes , Escherichia coli , Nanocompuestos/química , Hidrógeno/químicaRESUMEN
As an alternative to antibiotics, nanoparticles (NPs) are increasingly being used for targeting bacteria. Nanotechnology holds great potential in the treatment of bacterial infections. Although the mechanisms of antibacterial activity of NPs are not fully understood, widely accepted explanations include oxidative stress induction, metal ion release, and non-oxidative processes. Several simultaneous gene changes would be required in the bacterial cell, making it difficult for bacterial cells to develop resistance to NPs. One important application of nanoparticles is in dye removal. Nanoparticle structures can be utilized effectively as adsorbents due to their reduced size and increased surface area, by combining noble metals, Palladium-Nickel (Pd-Ni), with a carbon structure known as Vulcan Carbon (VC), it is anticipated that the consumption of precious metals can be reduced while benefiting from the enhanced properties of the bimetallic structure. The PdNi@VC structure was synthesized using the microwave synthesis technique. Characterization techniques such as Transmission Electron Microscope (TEM) and X-Ray diffraction (XRD) were employed to confirm the formation of the bimetallic structure. According to the Debye-Scherrer equation, the size is 2.74 nm. In addition, photodegradation assays using simulator solar radiation yielded 67% efficacy against Safranine dye. In addition, The PdNi@VC had a high percentage of bacterial inhibition at the concentration of 200 g/ml against Staphylococcus aureus (S.aureus), and Escherichia coli (E.coli). This study focuses on the synthesis of bimetallic nanoparticles for antibacterial applications and investigates their effectiveness in dye removal from wastewater. The obtained results provide valuable insights for the implementation of innovative methods in these areas.
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Nanopartículas del Metal , Nanopartículas , Níquel/química , Paladio/farmacología , Paladio/química , Nanopartículas del Metal/química , Carbono/química , Microondas , Antibacterianos/química , Difracción de Rayos XRESUMEN
In this study, an innovative nanomaterial was synthesized for hydrogen production from methanolysis on sodium borohydride (NaBH4) in order to be a solution for future energy problems. The nanocomposite containing FeCo, which does not contain noble metals, and whose support material is Polyvinylpyrrolidone (PVP), was synthesized by means of a thermal method. TEM, XRD and FTIR characterization methods were used for the analysis of the morphological and chemical structure of the nanocomposite. Nanocomposite particle size was found to be 2.59 nm according to XRD analysis, and 5.45 nm according to TEM analysis for scale of 50 nm. For catalytic properties of nanomaterial in the methanolysis reaction of NaBH4, temperature, catalyst, substrate, and reusability experiments were carried out and kinetic calculations were obtained. Among the activation parameters of FeCo@PVP nanoparticles, turnover frequency, enthalpy, entropy and activation energy were calculated as 3858.9 min-1, 29.39 kJ/mol, -139.7 J/mol.K, and 31.93 kJ/mol, respectively. As a result of the reusability test of the obtained FeCo@PVP nanoparticles catalysts, which was carried out for 4 cycles, the catalytic activity was 77%. Catalytic activity results are given in comparison with the literature. In addition, the photocatalytic activity of FeCo@PVP NPs was evaluated against MB azo dye under solar light irradiation for 75 min and was found to be as 94%.
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Nanocompuestos , Nanopartículas , Luz Solar , Compuestos Azo , Iluminación , Nanocompuestos/química , HidrógenoRESUMEN
In this study, Silver-Platinum (Pt-Ag) bimetallic nanoparticles were synthesized by the biogenic reduction method using plant extracts. This reduction method offers a highly innovative model for obtaining nanostructures using fewer chemicals. According to this method, a structure with an ideal size of 2.31 nm was obtained according to the Transmission Electron Microscopy (TEM) result. The Pt-Ag bimetallic nanoparticles were characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), and Ultraviolet-Visible (UV-VIS) spectroscopy. For the electrochemical activity of the obtained nanoparticles in the dopamine sensor, electrochemical measurements were made with the Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) methods. According to the results of the CV measurements taken, the limit of detection (LOD) was 0.03 µM and the limit of quantification (LOQ) was 0.11 µM. To investigate the antibacterial properties of the obtained Pt-Ag NPs, their antibacterial effects on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria were investigated. In this study, it was observed that Pt-Ag NPs, which were successfully synthesized by biogenic synthesis using plant extract, exhibited high electrocatalytic performance and good antibacterial properties in the determination of dopamine (DA).
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Nanopartículas del Metal , Nanopartículas del Metal/química , Dopamina , Staphylococcus aureus , Plata/química , Escherichia coli , Antibacterianos/química , Espectroscopía Infrarroja por Transformada de Fourier , Extractos Vegetales/químicaRESUMEN
In this study, titanium dioxide- Pluronics @F127/functionalized -multi walled carbon nanotubes (TiO2-F127f-/MWCNT) nanocatalysts were prepared, characterized, and used in methylene blue (MB) degradation under ultrasonic conditions. The characterization studies were performed using TEM, SEM, and XRD analyses to reveal the morphological and chemical properties of TiO2-F127/MWCNT nanocatalysts. To detect the optimum parameters for MB degradation using TiO2-F127/f-MWCNT nanocatalysts, several experimental parameters were conducted at various conditions such as different temperatures, pH, catalyst amount, hydrogen peroxide (H2O2) concentration, and various reaction contents. Transmission electron microscopy (TEM) analyses showed that TiO2-F127/f-MWCNT nanocatalysts consisted of a homogenous structure and have a 12.23 nm particle size. The crystalline particle size of TiO2-F127/MWCNT nanocatalysts was found to be 13.31 nm. Scanning electron microscope (SEM) analyses revealed the surface structure of TiO2-F127/f-MWCNT nanocatalysts turned to be modified after TiO2 loaded on MWCNT. Under the optimum conditions; pH: 4, MB concentration: 25 mg/L, H2O2 concentration: 30 mol/L, reaction time: and catalyst dose: 24 mg/L, chemical oxygen demand (COD) removal efficiency reached a maximum of 92%. To detect the radical effectiveness, three scavenger solvents were tested. Reuse experiments revealed that TiO2-F127/f-MWCNT nanocatalysts retained 84.2% catalytical activity after 5 cycles. Gas chromatography-mass spectrometry (GC-MS) was successfully used to identify the generated intermediates. Based on the experimental results, it has been suggested that â¢OH radicals are the main active species responsible for the degradation reaction in the presence of the TiO2-F127/f-MWCNT nanocatalysts.
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Nanotubos de Carbono , Poloxámero , Azul de Metileno/química , Nanotubos de Carbono/química , Peróxido de Hidrógeno , Catálisis , Titanio/químicaRESUMEN
The storage and shelf life of the fig, which has a sensitive fruit structure, is short, and this results in excessive economic losses. In a study carried out to contribute to the solution of this problem, the effect of postharvest putrescine application at different doses (0, 0.5, 1.0, 2.0, and 4.0 mM) on fruit quality characteristics and biochemical content during cold storage in figs was determined. At the end of the cold storage, the decay rate and weight loss in the fruit were in the ranges of 1.0-1.6% and 1.0-5.0 %, respectively. The decay rate and weight loss were lower in putrescine-applied fruit during cold storage. Putrescine application had a positive effect on the changes in fruit flesh firmness values. The SSC rate of fruit varied between 14 and 20%, while significant differences in the SSC rate occurred depending on storage time and putrescine application dose. With putrescine application, the decrease in the acidity rate of the fig fruit during cold storage was smaller. At the end of the cold storage, the acidity rate was between 1.5-2.5% and 1.0-5.0. Putrescine treatments affected total antioxidant activity values and changes occurred in total antioxidant activity depending on the application dose. In the study, it was observed that the amount of phenolic acid in fig fruit decreased during storage and putrescine doses prevented this decrease. Putrescine treatment affected the changes in the quantity of organic acids during cold storage, and this effect varied depending on the type of organic acid and the length of the cold storage period. As a result, it was revealed that putrescine treatments can be used as an effective method to maintain postharvest fruit quality in figs.
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In the study, a new bimetallic catalyst was synthesized for methanol oxidation using multi-walled carbon nanotube (MWCNT)-supported platinum-osmium (PtOs) nanoparticles (PtOs@MWCNT NPs). The morphological structures of the prepared NPs were examined using different techniques, such as scanning electron microscopy (SEM) and X-ray diffraction (XRD). The electrochemical characterization of the synthesized PtOs@MWCNT catalysts, such as chronoamperometry (CA), cyclic voltammetry (CV), scan rate (SR) analysis, cyclic catalytic test, and electrochemical surface area (ECSA) evaluation, were performed in an alkaline medium. From the results obtained, the size of the NPs was found to be 3.12 nm according to the Debye-Schrrer equation, and the MWCNTs were clearly observed by SEM imaging. After the characterization of the prepared nanomaterials, the PtOs@MWCNT catalysts were employed in the methanol oxidation reaction, and a high oxidation current value of 220.86 mA cm-2 was observed. Besides, according to the CA results, the catalyst exhibited high stability for 4000 s, and it was seen that Os metal improved the catalytic activity of the main catalyst. These results show that the PtOs@MWCNT catalyst is highly stable and reusable, and provides high electrocatalytic activity in the methanol oxidation reaction. Moreover, the obtained catalyst gave ideal results in terms of CO tolerance and activity. These data show that the obtained catalyst will provide significant improvement and superior efficiency in fuel-cell applications.
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Various impurities found nowadays in water can be detrimental to human health. This work focused on utilizing Fe3O4@MnO2 nanocomposite for cleaning organic contaminants from water, including rhodamine B (RhB) and Escherichia coli (E. coli). Analysis methods such as XRD, UV-vis, TEM, and FTIR were used to describe the nanocomposite. The results showed that the developed nanocomposite has good photocatalytic activity against pollutants in wastewater. The E. coli was destroyed after 90 min, and the RhB photodegradation rate was 75%. Moreover, the Fe3O4@MnO2 efficiency as a catalyst for producing hydrogen as an alternative energy source was tested. According to the calculations, the nanomaterial's turnover frequency, activation energy, enthalpy, and entropy are 1061.3 h-1, 28.93 kJ/mol, 26.38 kJ/mol, and -128.41 J/mol.K, respectively. Four reusability tests were completed, and the average reusability was 78%. The obtained data indicated the excellent potential for the developed Fe3O4@MnO2 nanomaterial to act as an adsorbent, thus representing an alternative to the classical depollution methods. This study showed that nanoparticles have a photocatalytic effect against pathogenic bacteria and RhB azo dye in polluted waters and offer an effective catalytic activity to produce hydrogen as an alternative energy source.
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Escherichia coli , Aguas Residuales , Humanos , Óxidos , Hidrólisis , Compuestos de Manganeso , Agua , Colorantes , TextilesRESUMEN
Activated carbon (AC) supported palladium cobalt bimetallic nanoparticles (PdCo@AC NPs) were obtained by green synthesis method using Cinnamomum verum (C. Verum) extract. The obtained NPs were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Crystallography (XRD), Transmission Electron Microscope (TEM) and Ultraviolet Visible (UV-VIS) spectroscopy, and the functional groups and morphology of the nanoparticle were elucidated. The resulting particle size was found to be 2.467 nm. NPs were evaluated using Cyclic Voltammetry (CV), Scan Rate (SR), and Differential Pulse Voltammetry (DPV) techniques for potential dopamine sensors application. According to the obtained DPV results, Limit of Detection (LOD) and Limit of Quantitation (LOQ) values are found to be 5.68 pM and 17.21 pM, respectively. It was also observed that AC supported PdCo nanoparticles obtained from C. verum extract sensed dopamine quite well. Besides, to examine the antibacterial properties of NPs, antibacterial analyzes were performed with Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus). It was observed that it showed good antibacterial properties against gram positive (S. aureus) and gram negative (E. coli) bacteria. The study gave important results in terms of the synthesis of bimetallic NPs using the green synthesis method and their usability in different areas. With this study, it was observed that a good antibacterial dopamine sensor were obtained with the successful biogenic synthesis of AC supported PdCo bimetallic NPs.