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2.
PLoS One ; 19(6): e0305272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38941302

RESUMO

This article represents a novel study of the design and analysis of a wind turbine system that includes a line-side permanent magnet synchronous generator (PMSG) with an ultra-step-up DC-DC converter for voltage regulation. Integrating renewable energy sources such as wind power into the grid requires efficient and reliable power conversion systems to handle fluctuating power and ensure a stable power supply. The wind turbine system utilizes a PMSG, which offers several advantages over traditional induction generators, including higher efficiency, reduced maintenance, and better power quality. The line-side configuration allows for increased control and flexibility, allowing the system to respond dynamically to grid conditions. This wind turbine system involves the integration of a grid-side PMSG-fed DC-DC converter between the PMSG and the grid. The converter enables a seamless flow of electricity between the wind turbine and the grid. By actively controlling the intermediate circuit voltage, the converter efficiently regulates the output voltage of the wind turbine and thus enables constant power generation regardless of fluctuating wind speeds. The simulation outcomes illustrate the efficacy of the proposed system in achieving voltage regulation and seamless integration with the grid. Performance is evaluated under various operating conditions and compared to conventional wind turbines.


Assuntos
Fontes de Energia Elétrica , Eletricidade , Vento , Energia Renovável , Desenho de Equipamento
3.
PLoS One ; 19(5): e0300145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38743740

RESUMO

Integration of renewable energy sources (RES) to the grid in today's electrical system is being encouraged to meet the increase in demand of electrical power and also overcome the environmental related problems by reducing the usage of fossil fuels. Power Quality (PQ) is a critical problem that could have an effect on utilities and consumers. PQ issues in the modern electric power system were turned on by a linkage of RES, smart grid technologies and widespread usage of power electronics equipment. Unified Power Quality Conditioner (UPQC) is widely employed for solving issues with the distribution grid caused by anomalous voltage, current, or frequency. To enhance UPQC performance, Fractional Order Proportional Integral Derivative (FOPID) is developed; nevertheless, a number of tuning parameters restricts its performance. The best solution for the FOPID controller problem is found by using a Coati Optimization Algorithm (COA) and Osprey Optimization Algorithm (OOA) are combined to make a hybrid optimization CO-OA algorithm approach to mitigate these problems. This paper proposes an improved FOPID controller to reduce PQ problems while taking load power into account. In the suggested model, a RES is connected to the grid system to supply the necessary load demand during the PQ problems period. Through the use of an enhanced FOPID controller, both current and voltage PQ concerns are separately modified. The pulse signal of UPQC was done using the optimal controller, which analyzes the error value of reference value and actual value to generate pulses. The integrated design mitigates PQ issues in a system at non-linear load and linear load conditions. The proposed model provides THD of 12.15% and 0.82% at the sag period, 10.18% and 0.48% at the swell period, and 10.07% and 1.01% at the interruption period of non-linear load condition. A comparison between the FOPID controller and the traditional PI controller was additionally taken. The results showed that the recommended improved FOPID controller for UPQC has been successful in reducing the PQ challenges in the grid-connected RESs system.


Assuntos
Algoritmos , Energia Renovável , Fontes de Energia Elétrica , Modelos Teóricos , Eletricidade
4.
PLoS One ; 19(5): e0301522, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776325

RESUMO

The design of a power electronic interface for high voltage difference DC buses is a key aspect in DC microgrid applications. A multi-port non isolated interleaved high-voltage gain bidirectional converter, which facilitates bidirectional power transfer and islanded operation in a DC microgrid, is presented in this paper. The forward high-voltage transfer ratio is achieved using a voltage multiplier circuit, and the high-gain step-down power conversion is performed using a resonant power module. A novel power transfer selection algorithm is proposed to control power flow among the interfaces of the RES, ESS, and DC grid converters, which utilizes the net power difference as the basis for switching the converter. The proposed converter is simulated for a 24 V PV source, 12 V battery, and 400 V DC grid interface using MATLAB/SIMULINK. A 200 W hardware prototype is implemented. The simulation results for voltages, currents, and power flow among RES, ESS, and microgrid DC bus proved an excellent voltage regulation, efficient power conversion, and a feasible duty cycle range with high voltage gain. These observations are validated through equivalent experimental results. A comparison is made regarding achieved gain, component sizing, achievable power transfer modes, efficiency, and control complexity with existing converters for DC microgrid applications. The presented topology proved to be a better interface with multiple-mode support with high efficiency.


Assuntos
Fontes de Energia Elétrica , Algoritmos , Desenho de Equipamento , Simulação por Computador
5.
Sci Rep ; 14(1): 11066, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745031

RESUMO

The development of DC microgrids is reliant on multi-input converters, which offer several advantages, including enhanced DC power generation and consumption efficiency, simplified quality, and stability. This paper describes the development of a multiple input supply based modified SEPIC DC-DC Converter for efficient management of DC microgrid that is powered by two DC sources. Here Multi-Input SEPIC converter offers both versatility in handling output voltage ranges and efficiency in power flow, even under challenging operating conditions like lower duty cycle values. These features contribute to the converter's effectiveness in managing power within a DC microgrid. In this configuration, the DC sources can supply energy to the load together or separately, depending on how the power switches operate. The detailed working states with equivalent circuit diagrams and theoretical waveforms, under steady-state conditions, are shown along with the current direction equations. This paper also demonstrates the typical analysis of large-signal, small-signal, steady-state modeling techniques and detailed design equations. The proposed configuration is validated through the conceptual examination using theoretical and comprehensive MATLAB simulation results. Detailed performance analysis has been done for different cases with various duty ratios. Finally, to show the competitiveness, the multi-input SEPIC topology is compared with similar recent converters.

6.
ACS Omega ; 9(11): 12602-12610, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524437

RESUMO

Background: Head and neck squamous cell carcinoma (HNSCC) is one of the major types of cancer, with 900,000 cases and over 400,000 deaths annually. It constitutes 3-4% of all cancers in Europe and western countries. As early diagnosis is the key to treating the disease, reliable biomarkers play an important role in the precision medicine of HNSCC. Despite treatments, the survival rate of cancer patients remains unchanged, and this is mainly due to the failure to detect the disease early. Thus, the objective of this study is to identify reliable biomarkers for head and neck cancers for better healthcare management. Methods: In this study, all available, curated human genes were screened for their expression against HNSCC TCGA patient samples using genomic and proteomic data by various bioinformatic approaches and datamining. Docking studies were performed using AutoDock or online virtual screening tools for identifying potential ligands. Results: Sixty genes were short-listed, and most of them show a consistently higher expression in head and neck patient samples at both the mRNA and the protein level. Irrespective of human papillomavirus (HPV) status, all of them show a higher expression in cancer samples. The higher expression of 30 genes shows adverse effects on patient survival. Out of the 60 genes, 12 genes have crystal structures and druggable potential. We show that genes such as GTF2H4, HAUS7, MSN, and MNDA could be targets of Pembrolizumab and Nivolumab, which are approved monoclonal antibodies for HNSCC. Conclusion: Sixty genes are identified as potential biomarkers for head and neck cancers based on their consistent and statistically significantly higher expression in patient samples. Four proteins have been identified as potential drug targets based on their crystal structure. However, the utility of these candidate genes has to be further tested using patient samples.

7.
Chemosphere ; 341: 139955, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37652247

RESUMO

The photocatalytic removal of toxic chemical pollutants from wastewater has garnered significant attention in recent times owing to its notable removal efficiency, cost-effectiveness, and eco-friendly characteristics. Nonetheless, this catalytic process necessitates augmented charge separation and distinctive interface properties to facilitate catalytic reactions for water treatment applications. Therefore, in the current study, novel g-C3N4/Ni-doped ZrO2 heterostructured hybrid catalysts have been synthesized via a hydrothermal approach. Microscopic studies reveal that ZrO2 nanospheres were distributed on the layered-like 2D structure of g-C3N4 nanosheets. Electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (UV-DRS), and photoluminescence (PL) characterizations were employed to investigate the impact of bandgap, electron-hole recombination, charge transfer, and interface properties on the catalytic performance of g-C3N4/ZrO2 hybrids. XRD analysis confirmed that the Ni-ions do not disturb the host lattice crystal structure and heterostructure development between g-C3N4 and doped ZrO2 sample. Structurally, Ni-doped nanoparticles were found to be equally superficially dispersed on g-C3N4 sheets. Optical analysis results suggest that the hybrid catalyst possesses a narrow bandgap of 2.56 eV. The synthesized photocatalyst degraded rhodamine B (RhB) and tetracycline (TC) with ∼92% and ∼89% degradation efficiency, respectively. Heterostructured hybrid catalysts showed superior degradation rate constants than other catalysts. This might be attributed to the sufficient separation of electron-hole due to the development of a heterojunction. The radical scavenging experiments suggested that O2●- and ●OH radicals contributed substantially to the dye elimination activity of the composite. Therefore, the synthesized novel nanohybrid catalysts in this study present an efficient and straightforward synthesis method for the efficient removal of toxins from wastewater under visible light irradiation.


Assuntos
Poluentes Ambientais , Nanosferas , Níquel , Fotólise , Águas Residuárias , Luz
8.
Environ Res ; 225: 115585, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36854374

RESUMO

In recent years, antibiotic drugs have been extensively used owing to increased industrial growth, and this has created issues related to drinking water and a green environment. Different techniques have been used to resolve these issues, among which heterogeneous photocatalysis has been widely explored for the elimination of toxic compounds from wastewater resources. In this study, ZnIn2S4, g-C3N4, and ZnIn2S4/g-C3N4 hybrid heterostructured composites are synthesized via hydrothermal method and used these (i) for the removal of antibiotic sulfamethoxazole pollutant and (ii) photoelectrochemical water oxidation. The nanomaterials were characterized using X-ray diffraction, Scanning electron microscopy, transmission electron microscopy, and UV-vis spectroscopy. The developed hybrid heterostructured composites were able to degrade sulfamethoxazole pollutants as well as offer improved photoelectrochemical properties compared to pristine samples. The catalytic performance of the materials developed under visible light irradiation was greatly improved for the degradation of the antibiotic drug up to 89.4% in 2 h. Moreover, the hybrid heterostructured photoelectrode showed a better photocurrent density (8.68 mA/cm2) and exhibited ∼19.2 and 29.9 times greater photocurrent density than the pristine photoelectrodes. Such a considerably increased catalytic activity was attributed to the active separation of charge carriers and transmission. The study offers an innovative approach to develop effective catalysts, and for the degradation of sulfamethoxazole as well as the PEC properties for hydrogen production.


Assuntos
Antibacterianos , Poluentes Ambientais , Sulfametoxazol , Luz , Água , Oxirredução
9.
Chemosphere ; 322: 138146, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36806805

RESUMO

Novel heterostructured hybrid catalysts are essential for the efficient photocatalytic removal of organic pollutants from wastewater generated by the pharmaceutical and textile industries. In this study, novel g-C3N4/BiVO4 nanohybrid catalysts were prepared using a solvothermal technique, and examined their structural and optical properties using different characterizations. The X-ray diffraction analysis confirmed the monoclinic crystal phase of BiVO4. Field emission scanning electron microscopy (FESEM) images revealed that g-C3N4 sheets anchored on the surface of BiVO4 nanospheres. X-ray photoelectron spectroscopy (XPS) analysis confirmed the oxidation states of g-C3N4/BiVO4 composite sample. UV-Vis DRS spectroscopy analysis revealed that the composite (2.08 eV) sample had a reduced bandgap compared to other samples. The photocatalytic properties of the prepared samples were tested in the presence of organic methylene blue (MB) and antibiotic tetracycline (TC) pollutants under visible light illumination. The hybrid composite catalyst exhibited enhanced photocatalytic degradation efficiency of MB (88%) and TC (89%) pollutants at elevated rate constants of 0.0128 and 0.01174 min-1, respectively. The improved catalytic performance of the composite catalyst is due to the heterojunctions between g-C3N4 and BiVO4 that successfully reduced the rate of charge carrier recombination in the catalyst system. Scavenger experiments revealed that O2●- and h+ radicals played a main role in the degradation of the chemical pollutants. The developed g-C3N4/BiVO4 heterostructured catalyst is a suitable candidate for removing contaminants from industrial wastewater because of its facile fabrication and exceptional photocatalytic activity under visible light irradiation.


Assuntos
Poluentes Ambientais , Fotólise , Águas Residuárias , Espectroscopia Fotoeletrônica , Microscopia Eletrônica de Varredura , Luz , Antibacterianos , Tetraciclina
10.
Environ Res ; 217: 114923, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435491

RESUMO

The worldwide energy calamity and ecological disturbances demand materials that can remove harmful contaminants from the polluted water. Recently, semiconductor-based catalytic dye removal has created much consideration due to its high efficacy and eco-friendly contaminated water treatment processes. Vanadium oxide (V2O5) has attracted superior attention as a catalyst due to its robust oxidation power, chemical inertness, and stability against photodegradation. In this study, pristine and cobalt (Co)-doped V2O5 samples were synthesized by solvothermal method and examined for their photo-degradation activity and photoelectrochemical (PEC) water oxidation properties. The orthorhombic crystal phase was confirmed by X-ray diffraction (XRD), hexagonal-shaped morphology was observed by scanning electron microscope (SEM) and reduced optical band gap (2.01 eV) was noticed for doped V2O5 catalyst compared to the pristine (2.20 eV) catalyst. The doped V2O5 catalyst exhibited enhanced photodegradation of crystal violet CV (92.7%) and Cr (VI) reduction (90.5%) after 100 min of light irradiation. The doped photocatalyst exhibited approximately 2.1 and 1.9-fold enhancement of photodegradation of CV and Cr(VI) reduction, respectively. The doped electrode showed improved photocurrent density (0.54 mA/cm-2) compared to pristine electrode (0.12 mA/cm-2). Moreover, the doped electrode showed reduced charge-transfer resistance and enhanced charge-transfer properties compared to those of the pristine electrode. Hence, the prepared hexagonal-shaped V2O5 is a suitable material for the elimination of environmental contaminants from the polluted water as well as water splitting for hydrogen generation.


Assuntos
Cobalto , Poluentes Ambientais , Oxirredução , Óxidos/química , Fotólise , Catálise
11.
Chemosphere ; 311(Pt 1): 137015, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36342024

RESUMO

Photodegradation of organic pollutants using metal oxides has shown extraordinary promise owing to the catalytic efficacy, low cost, less noxiousness, and good chemical constancy. In this research, pure and transition metal ions (Cu)-doped V2O5 nanosheets were synthesized and investigated for their photocatalytic efficiency using methyl blue (MB) and rhodamine B (RhB) organic dye pollutants under visible light irradiation. The orthorhombic crystal phase was confirmed by XRD analysis, which exhibited a stable phase upon incorporating Cu dopant ions. Optical properties were examined using optical absorption spectroscopy, while a reduced band gap was observed in the doped V2O5 nanosheets over the undoped sample. EIS analysis confirmed lower charge resistance in doped V2O5 nanosheets. The Cu dopant incorporation into the host matrix considerably enhanced photodegradation efficiency for MB and RhB impurities under light illumination. The improvement in catalytic efficacy is attributed to dopant ions that can separate photoinduced charge carriers and the quick movement of the charge. Moreover, comparatively lesser crystalline size, improved specific surface area, and hydroxyl group onto the catalyst surface are quite advantageous to offer better photocatalytic activity of Cu-doped V2O5 nanosheets.


Assuntos
Poluentes Ambientais , Fotólise , Poluentes Ambientais/análise , Luz , Catálise , Corantes/química
12.
Environ Res ; 217: 114672, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36356664

RESUMO

Photocatalytic dye degradation is a method of environmental degradation that is commonly used to eliminate various pollutants produced by pharmaceutical and textile industries. Herein, pure and chromium (Cr)-doped SnO2 nanoflakes were synthesized using a simple facile hydrothermal method and photocatalytic properties were studied under visible light illumination. In addition, photoelectrochemical (PEC) water oxidation properties were also studied using the prepared samples. Doping of transition metal ions introduces structural defects, which narrow the band gap of host sample, resulting in high catalytic activity. The synthesized doped SnO2 displayed a rutile tetragonal crystal phase with a nanoflakes-like surface morphology having no other contaminations. The optical band gap of Cr-doped SnO2 nanoflakes was significantly reduced (2.48 eV) over the pure sample (3.32 eV), due to successful incorporation of Cr ions into the host lattice. Furthermore, the dye removal efficiency of these nanoflakes was investigated for methyl orange (MO) and tetracycline (TC) organic contaminations. The Cr-doped SnO2 nanoflakes exhibited superior photodegradation with 87.8% and 90.6% dye removal efficiency, within 90 min of light illumination. PEC water oxidation analysis showed that the doped photoelectrode achieved enhanced photocurrent density and showed a higher photocurrent density (1.08 mA cm-2) over that of the undoped electrode (0.60 mA cm-2). Electrochemical impedance spectroscopy (EIS) showed that doped electrodes exhibited lesser charge resistance than the pure electrode. The synthesized Cr-doped SnO2 nanoflakes are suitable for water oxidation and photodegradation of organic pollutants. Thus, we strongly believe that the obtained results in this report will continue to provide new opportunities for the improvement of effective visible light photocatalysts for industrial wastewater treatment and water splitting for H2 generation.


Assuntos
Poluentes Ambientais , Água , Água/química , Cromo , Oxirredução , Luz
13.
Ann Afr Med ; 21(4): 395-402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36412341

RESUMO

Background: Probiotic organisms Lactobacillus reuteri UBLRU-87 and Bifidobacterium bifidum UBBB-55 were proven to be acting against the caries causing organisms. Aims: This study aims to evaluate the influence of Lactobacillusreuteri, Bifidobacterium bifidum and their blend on Mutans streptococci count in the saliva of children, and also to appraise the sustainability of their action. Materials and Methods: A randomized, double-blind and placebo-controlled study with 60 subjects (15 in each group) in 6-14 years of age group. The children consumed curd containing Bifidobacterium bifidum (UBBB 55, MTCC 5398) and Lactobacillus reuteri (UBLRu 87, MTCC 5403), and their blend once daily for 14 days. The control group received curd with no Probiotic in it. The saliva samples were collected just before the curd (T0) administration to establish baseline levels of mutans streptococci and after a day of the final consumption of the curd (T14). The follow-up samples at 21 days (T21) and 28 days (T28) after the baseline were also collected to know the sustainability of action probiotics on mutans streptococci if any. Results: Statistically significant reduction of mutans streptococci is observed in the group administered with Lactobacillus reuteri and the effect lasted up to a minimum of 21 days. Mixed cultures are seemed to be not effective against the oral microorganisms. Conclusions: The probiotic organism Lactobacillus reuteri in Indian curd is effective on salivary mutans streptococci, and the effect was sustained for some period after the administration.


Résumé Contexte: Il a été démontré que les organismes probiotiques Lactobacillus reuteri UBLRU-87 et Bifidobacterium bifidum UBBB-55 agissaient contre les organismes responsables des caries. Objectifs: Cette étude vise à évaluer l'influence de Lactobacillus reuteri, Bifidobacterium bifidum et de leur mélange sur le nombre de streptocoques Mutans streptocoques dans la salive des enfants, et également d'évaluer la durabilité de leur action. Conception de l'étude: Une étude randomisée, en double aveugle et placebo avec 60 sujets (15 dans chaque groupe) dans le groupe d'âge 6-14 ans. Les enfants ont consommé du lait caillé contenant du Bifidobacterium bifidum (UBBB 55, MTCC 5398) et Lactobacillus reuteri (UBLRu 87, MTCC 5403), et leur mélange une fois par jour pendant 14 jours. Le groupe témoin a reçu du lait caillé sans probiotique. Les échantillons de salive ont été prélevés juste avant l'administration du lait caillé (T0) pour établir les niveaux de base des streptocoques mutans. Les échantillons de salive ont été prélevés juste avant l'administration du lait caillé (T0) pour établir les niveaux de base de streptocoques mutans et un jour après la consommation finale du lait caillé (T14). Les échantillons de suivi à 21 jours (T21) et 28 jours (T28) après la ligne de base ont également été collectés pour connaître les niveaux de streptocoques mutans. la ligne de base ont également été collectés pour connaître la durabilité de l'action des probiotiques sur les streptocoques mutans, le cas échéant. Résultats: Réduction statistiquement significative statistiquement significative des streptocoques mutans est observée dans le groupe administré avec Lactobacillus reuteri et l'effet a duré jusqu'à un minimum de 21 jours. Les cultures mixtes ne semblent pas être efficaces contre les micro-organismes oraux. Conclusions: L'organisme probiotique Lactobacillus reuteri dans le caillé indien est efficace sur la salive Indian curd est efficace sur les streptocoques mutans salivaires, et l'effet a été maintenu pendant une certaine période après l'administration. Mots-clés: Caillé, probiotique, mutans salivaires.


Assuntos
Limosilactobacillus reuteri , Probióticos , Criança , Humanos , Saliva/microbiologia , Streptococcus mutans , Probióticos/uso terapêutico , Método Duplo-Cego
14.
Chemosphere ; 308(Pt 2): 136414, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36099985

RESUMO

Photodegradation is an eco-friendly degradation process routinely employed for the removal of various pollutants produced by pharmaceutical and textile industries. In this work, g-C3N4 sheets (g-CN) supported with Fe-doped ZrO2 nanoparticles have been prepared via a facile hydrothermal method as photocatalysts for the effective photodegradation of methyl orange (MO) and tetracycline (TC). The as-prepared photocatalysts were characterized by using a wide range of techniques to understand the origin of their superior photodegradation performance. Structurally, Fe-doped ZrO2 nanoparticles were found to be uniformly superficially distributed on g-C3N4. The addition of Fe-doped ZrO2 nanoparticles was also found to improve the surface area and light absorption capacity of pure g-CN. It was further revealed that the development of heterojunctions between g-C3N4 and Fe-doped ZrO2 nanoparticles effectively reduced the recombination rate of electron and hole pairs within the photocatalyst system, resulting in improved photocatalytic activity. Previous studies have pointed at the superoxide radical anions (˙O2-) and (OH·) as being primarily responsible for the degradation of MO and TC species, leading us to hypothesize that the g-FZ composite works via a possible free-radical based catalytic mechanism to support the photodegradation process.


Assuntos
Poluentes Ambientais , Nanopartículas , Antibacterianos , Compostos Azo , Luz , Preparações Farmacêuticas , Superóxidos , Tetraciclina
15.
Comput Intell Neurosci ; 2022: 3170244, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35855796

RESUMO

Over the last few decades, forest fires are increased due to deforestation and global warming. Many trees and animals in the forest are affected by forest fires. Technology can be efficiently utilized to solve this problem. Forest fire detection is inevitable for forest fire management. The purpose of this work is to propose deep learning techniques to predict forest fires, which would be cost-effective. The mixed learning technique is composed of YOLOv4 tiny and LiDAR techniques. Unmanned aerial vehicles (UAVs) are promising options to patrol the forest by making them fly over the region. The proposed model deployed on an onboard UAV has achieved 1.24 seconds of classification time with an accuracy of 91% and an F1 score of 0.91. The onboard CPU is able to make a 3D model of the forest fire region and can transmit the data in real time to the ground station. The proposed model is trained on both dense and rainforests in detecting and predicting the chances of fire. The proposed model outperforms the traditional methods such as Bayesian classifiers, random forest, and support vector machines.


Assuntos
Incêndios , Incêndios Florestais , Animais , Teorema de Bayes
16.
Chemosphere ; 295: 133851, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35124089

RESUMO

Pure ZrO2, graphitic carbon nitride, Cu-doped ZrO2 nanoparticles (Cu-Zr), and doped Cu-Zr nanoparticles decorated on the g-C3N4 surface (g-CuZr nanohybrids) were successfully prepared by a hydrothermal technique. Synthesized catalysts were examined by XRD, FE-SEM, TEM, UV-Vis spectroscopy, photoluminescence (PL), and BET surface measurements, respectively. The photocatalytic reduction of Cr(VI) photoreduction as well as energy storage supercapacitor applications were thoroughly investigated. The g-CuZr hybrid photocatalyst outperformed other pristine photocatalysts in terms of light absorption and catalytic Cr(VI) reduction performance under stimulated solar light irradiation. Furthermore, methylene blue (MB) was used as a photosensitizer to further improve the Cr(VI) photoreduction performance. In precise, the heterostructured hybrid catalyst exhibited improved photocatalytic Cr(VI) photoreduction activity (∼88.1%) in 5 mg/L MB solution over other catalysts. Moreover, the decoration of Cu-Zr on the surface of g-C3N4 enhanced the absorption ability of light and catalytic Cr(VI) photoreduction performance. The PL, EIS, and transient photocurrent analysis demonstrated that the efficiency of the charge carrier's separation in the nanohybrid catalyst was superior over other catalysts. Furthermore, heterostructured g-CuZr nanohybrid electrode exhibited superior specific capacitance (297.2 F/g) over other electrodes, which are 5.5 folds (54.01 F/g), ∼2 folds (144.01 F/g) better than pure ZrO2 and g-C3N4 electrodes. Likewise, the nanohybrid electrode retained about 90% of the capacitive value after 2500 cycles over its initial capacitance.


Assuntos
Cromo , Nanopartículas , Catálise , Cromo/química , Fenômenos Físicos
17.
Indian J Med Microbiol ; 40(2): 306-308, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35144832

RESUMO

The Aeromonads are ubiquitous Gram-negative bacilli that cause community acquired, and healthcare associated infections. In this retrospective study we analysed clinical and microbiological characteristics of thirty-six culture proven Aeromonas infections. The most common species isolated was A.hydrophila. Clinical presentation included syndromes like skin and soft tissue infections (SSTI), urinary tract infections, and central line associated bloodstream infections (CLABSI). Most of the isolates were sensitive to aminoglycosides [97.2%], followed by 3 rd generation cephalosporins, quinolones and carbapenems. Overall mortality was 13.88% (5 out of 36 patients). A high index of suspicion is required for diagnosis and better outcomes.


Assuntos
Aeromonas , Infecções por Bactérias Gram-Negativas , Infecções Urinárias , Carbapenêmicos , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Masculino , Estudos Retrospectivos , Infecções Urinárias/microbiologia
18.
Indian J Crit Care Med ; 26(7): 877-878, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36864873

RESUMO

Background: Organophosphorus (OP) pesticides are extensively used both in developed and developing countries. Organophosphorus poisoning primarily occurs through occupational, accidental, and suicidal exposures. Toxicity through parenteral injections is seldom reported and there are only very few case reports till date. Case presentation: We report a case of parenteral injection of 10 mL of OP compound (Dichlorvos 76%) into a swelling over the left leg. The compound was injected by the patient himself as adjuvant therapy for swelling. Initial manifestations included vomiting, abdomen pain, and excessive secretions followed by neuromuscular weakness. The patient was subsequently intubated and treated with atropine and pralidoxime. The patient did not improve with antidotes for OP poisoning, attributed to the depot the OP compound had formed. The swelling was excised and the patient immediately showed response to the treatment. Biopsy of the swelling showed granuloma and fungal hyphae. The patient developed intermediate syndrome during the ICU stay and was discharged after 20 days of hospital stay. How to cite this article: Jacob J, Reddy CHK, James J. "The Toxic Depot": Parenteral Insecticide Injection. Indian J Crit Care Med 2022;26(7):877-878.

19.
J Hazard Mater ; 423(Pt A): 127044, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523469

RESUMO

A simple hydrothermal approach was demonstrated for synthesizing a coupled NiFe2O4-ZnWO4 nanocomposite, wherein one-dimensional ZnWO4 nanorods were inserted into two-dimensional NiFe2O4 nanoplates. Herein, we evaluated the photocatalytic removal of Cr(VI), and degradation of tetracycline (TC) and methylene blue (MB) by the nanocomposite, as well as its ability to split water. The ZnWO4 nanorods enriched the synergistic interactions, upgraded the solar light fascination proficiency, and demonstrated outstanding detachment and migration of the photogenerated charges, as confirmed by a transient photocurrent study and electrochemical impedance spectroscopy measurements. Compared to pristine NiFe2O4 and ZnWO4, the NiFe2O4-ZnWO4 nanocomposite exhibited a higher Cr(VI) reduction (93.5%) and removal of TC (97.9%) and MB (99.6%). Radical trapping results suggested that hydroxyl and superoxide species are dominant reactive species, thereby facilitating the Z-scheme mechanism. Furthermore, a probable photocatalytic mechanism was projected based on the experimental results. The photoelectrochemical analysis confirmed that NiFe2O4-ZnWO4 exhibited minor charge-transfer resistance and large photocurrents. We propose a novel and efficient approach for designing a coupled heterostructured nanocomposites with a significant solar light ability for ecological conservation and water splitting.


Assuntos
Poluentes Ambientais , Óxido de Zinco , Catálise , Cromo , Compostos Férricos , Níquel , Óxidos , Tungstênio , Água , Zinco
20.
Chemosphere ; 287(Pt 2): 132081, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34500333

RESUMO

In recent times, the synthesis of metal nanoparticles (NPs) using plant extracts has recently emerged as an intriguing issue in the field of nanoscience and nanobiotechnology, with numerous advantages over conventional physicochemical approaches. In the current study, ZnO NPs were synthesized from Synadium grantii leaf extricate with varying Cu-dopant concentrations. In order to the synthesis of the pure and Cu-doped ZnO NPs, zinc nitrate hexahydrate and copper nitrate trihydrate were used as a precursor in leaf extracts of the plant. XRD, TEM, FTIR, XPS, and PL measurements were carried out to examine the physical and optical properties of the synthesized samples. The photocatalytic studies of the prepared samples were studied using Methylene blue (MB), Indigo Carmine (IC), and Rhodamine B (RhB) organic pollutants. The wurtzite crystal structure of synthesized samples was confirmed by XRD and TEM analysis. Further, the presence of functional groups in the prepared samples was confirmed by FTIR analysis. XPS analysis confirmed that the binding energies of a host material and dopant ions. The emission peaks identified at 424, 446 and 573 nm are associated with the electron movement from the deep donor level, zinc interstitial to the zinc vacancy and oxygen vacancy. 3% and 5% Cu-doped samples exhibited superior photocatalytic activity for MB, IC, and RhB dyes. The green synthesized ZnO NPs showed enriched photocatalytic performance, signifying that bio-synthesis can be an outstanding approach to develop versatile and environmental products.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Óxido de Zinco , Catálise , Azul de Metileno
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