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1.
J Colloid Interface Sci ; 668: 385-398, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38685164

RESUMEN

Desalination processes frequently require a lot of energy to generate freshwater and energy, which depletes resources. Their reliance on each other creates tension between these two vital resources. Herein, hierarchical MXene nanosheets and bismuth vanadate (Ti3C2/BiVO4)-derived microcapsules were synthesized for a photothermal-induced photoredox reaction for twofold applications, namely, solar-driven water evaporation and hydrogen (H2) production. For this purpose, flexible aerogels were fabricated by introducing Ti3C2/BiVO4 microcapsules in the polymeric network of natural rubber latex (NRL-Ti3C2/BiVO4), and a high evaporation rate of 2.01 kg m-2 h-1 was achieved under 1-kW m-2 solar intensity. The excellent performance is attributed to the presence of Ti3C2/BiVO4 microcapsules in the polymeric network, which provides balanced hydrophilicity and broadband sun absorption (96 %) and is aimed at plasmonic heating with microscale thermal confinement tailored by heat transfer simulations. Notably, localized plasmonic heating at the catalyst active sites of the Ti3C2/BiVO4 heterostructure promotes enhanced photocatalytic H2 production evolved after 4 h of reaction is 9.39 µmol, which is highly efficient than pure BiVO4 and Ti3C2. This method turns the issue of water-fuel crisis into a collaborative connection, presenting avenues to collectively address the anticipated demand rather than fostering competition.

2.
iScience ; 27(1): 108612, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38179065

RESUMEN

Proton conductors are typically developed by doping to introduce structural defects such as oxygen vacancies to facilitate ionic transport through structural bulk conduction mechanism. In this study, we present a novel electrochemical proton injection method via an in situ fuel cell process, demonstrating proton conduction in europium oxide (Eu2O3) through a surficial conduction mechanism for the first time. By tuning Eu2O3 into a protonated form, H-Eu2O3, we achieved an exceptionally high proton conductivity of 0.16 S cm-1. Distribution of relaxation time (DRT) analysis was employed to investigate the proton transport behavior and reveal the significant contribution of surface proton transport to the overall conductivity of Eu2O3. Remarkably, H-Eu2O3 exhibited a low activation energy for ionic transport, comparable to the best ceramic electrolytes available. The proton-coupled electron transfer (PCET) mechanism describes this novel surficial proton conduction mechanism. These findings provide new possibilities for developing advanced proton conductors with improved performance.

3.
J Family Med Prim Care ; 12(10): 2385-2391, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38074239

RESUMEN

Background: SARS-CoV-causing COVID-19 resulted in mortality, and the clinic-epidemiological profile at the time of admission of patients who died later could provide an insight into pathophysiological consequences due to infection. Method: Retrospective observational study of 64 RTPCR-confirmed COVID-19 non-survivors was conducted from April - June 2021 and January February 2022. Data were analyzed, and a P value<0.05 was taken as significant. Results: 60.94% and 39.06 % were males and females, and 26.57% & 73.43 % of patients had moderate and severe disease, respectively. Fever, cough, and dyspnea were the most common presenting symptoms. 78.12% and 21.88% had pre-existing (diabetes and hypertension were most common) and no co-morbidities, respectively. 65.62 & 17.19 % of patients had bilateral and unilateral ground glass opacities, respectively. Thrombocytopenia, lymphopenia, neutrophilia, elevated monocytes, and neutrophil-lymphocyte ratio (NLR) of 7.52 were hematological findings. D dimer was elevated. ABG showed low PaO2 and SPO2 %. ALT and AST were elevated. Tachycardia was also present. Compared to the first wave, no significant association of gender with severity was found. However, the percentage of male patients was higher. The association of the duration of stay and co-morbidity with disease severity was significant in both the first and subsequent waves of COVID-19. Conclusion: Co-morbidity, disease severity, and radiological lung opacities play a role in the outcome of COVID-19. The associated findings are hematological, renal, liver, cardiovascular, and arterial blood gas derangements.

4.
Nanotechnology ; 35(6)2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37879320

RESUMEN

Nickel-based oxides are selected for their inexpensive cost, well-defined redox activity, and flexibility in adjusting nanostructures via optimization of the synthesis process. This communique explores the field of energy storage for hydrothermally synthesized NiO/ZnO nanowires by analysing their capacitive behaviour. The p-type NiO was successfully built onto the well-ordered mesoporous n-type ZnO matrix, resulting in the formation of p-n heterojunction artefacts with porous nanowire architectures. NiO/ZnO nanowire-based electrodes exhibited much higher electrochemical characteristics than bare NiO nanowires. The heterojunction at the interface between the NiO and ZnO nanoparticles, their specific surface area, as well as their combined synergetic influence, are accountable for the high specific capacitance (Cs) of 1135 Fg-1at a scan rate of 5 mV s-1. NiO/ZnO nanowires show an 18% dip in initial capacitance even after 6000 cycles, indicating excellent capacitance retention and low resistance validated by electrochemical impedance spectroscopy. In addition, the specific capacitance, energy and power density of the solid state asymmetric capacitor that was manufactured by employing NiO/ZnO as the positive electrode and activated carbon as the negative electrode were found to be 87 Fg-1, 23 Whkg-1and 614 Wkg-1, respectively. The novel electrode based on NiO/ZnO demonstrates excellent electrochemical characteristics all of which point to its promising application in supercapacitor devices.

5.
Glob Chall ; 7(9): 2300091, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37745825

RESUMEN

Solar evaporation is a facile and promising technology to efficiently utilize renewable energy for freshwater production and seawater desalination. Here, the fabrication of self-regenerating hydrogel composed of 2D-MXenes nanosheets embedded in perovskite La 0.6Sr 0.4Co 0.2Fe 0.8O3- δ (LSCF)/polyvinyl alcohol hydrogels for efficient solar-driven evaporation and seawater desalination is reported. The mixed dimensional LSCF/Ti3C2 composite features a localized surface plasmonic resonance effect in the polymeric network of polyvinyl alcohol endows excellent evaporation rates (1.98 kg m-2 h-1) under 1 k Wm-2 or one sun solar irradiation ascribed by hydrophilicity and broadband solar absorption (96%). Furthermore, the long-term performance reveals smooth mass change (13.33 kg m-2) during 8 h under one sun. The composite hydrogel prompts the dilution of concentrated brines and redissolves it back to water (1.2 g NaCl/270 min) without impeding the evaporation rate without any salt-accumulation. The present research offers a substantial opportunity for solar-driven evaporation without any salt accumulation in real-life applications.

6.
RSC Adv ; 13(39): 27233-27243, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37701287

RESUMEN

Ceramic fuel cells presently hold an important position in the future of sustainable energy. However, new concepts and designs are vital for each individual cell's component materials to improve the overall power output and stability. The limited ionic conductivity of the electrolyte component is one major challenge among these. In the present work, we developed nanosheets with a cubic fluoride structure of CeO2 and introduced the di- and tri-valent doping of La and Sr to study their impact on oxygen vacancies and its ionic transport, keeping in mind the fact that CeO2 is reduced when exposed to a reducing atmosphere. The attained La- and Sr-doped fluorite structures of CeO2 exhibited good ionic conductivity of >0.05 S cm-1 at low temperature, and their use in a fuel cell resulted in achieving a power output of >900 mW cm-2 while operating at 550 °C. Therefore, we have found that laterally combining di- and tri-valent doping could be textured to give a highly oxygen-deficient CeO2 structure with high ionic transport. Furthermore, various microscopic and spectroscopic analyses, such as HR-TEM, XPS, Raman, UV-visible, EIS, and density functional theory, were applied to investigate the change in structural properties and mechanism of the ionic transport of the synthesized La and Sr co-doped CeO2 electrolyte. This work provides some new insights for designing high-ionic-conductivity electrolytes from low-cost semiconductor oxides for energy storage and conversion devices.

7.
iScience ; 26(6): 106869, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37275521

RESUMEN

The fuel cell's three layers-anode/electrolyte/cathode-convert fuel's chemical energy into electricity. Electrolyte membranes determine fuel cell types. Solid-state and ceramic electrolyte SOFC/PCFC and polymer based PEMFC fuel cells dominate fuel cell research. We present a new fuel cell concept using next-generation ceramic nanocomposites made of semiconductor-ionic material combinations. A built-in electric field driving mechanism boosts ionic (O2- or H+ or both) conductivity in these materials. In a fuel cell device, non-doped ceria or its heterostructure might attain 1 Wcm-2 power density. We reviewed promising functional nanocomposites for that range. Ceria-based and multifunctional semiconductor-ionic electrolytes will be highlighted. Owing to their simplicity and abundant resources, these materials might be used to make fuel cells cheaper and more accessible.

8.
Chem Commun (Camb) ; 59(41): 6223-6226, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37129587

RESUMEN

High-performing electrolytes at low operating temperatures have become an inevitable trend in the development of low-temperature solid oxide fuel cells (LT-SOFCs). Such electrolytes have drawn significant attention due to their appeal for high performance. Herein, we propose a new material by doping Y3+ into Gd2O3 for LT-SOFC electrolyte use. The prepared material was characterized in terms of crystal structure, surface, and interface properties, followed by its application in LT-SOFCs. YDG delivered promising SOFC performance with a power density of 1046 mW cm-2 at 550 °C along with high ionic conductivity of 0.19 S cm-1. Moreover, impedance spectra revealed that YDG exhibited the least ohmic resistance of 0.06-0.09 Ω cm2 at 550-460 °C. Furthermore, stable operation for 60 h demonstrated the chemical stability of the material in reduced temperature environments. Density function theory was also applied to analyze the electronic band structure and density of states of the synthesized sample. Our findings thus certify that YDG as a high-performing electrolyte at low operating temperatures.

9.
Int J Biol Macromol ; 240: 124367, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37031789

RESUMEN

This study aims to protect sensitive vitamins D, E, B1 and B2 by co-encapsulation in micro and nanoparticles of water chestnut starch for synergistic effects. The encapsulation efficiency, particle size, thermal properties and molecular configuration & interactions studies were analysed. The nano-sized starch with a particle size of 362 nm showed better encapsulation potential than micro-sized starch having an average particle size of 3.47 µm. The encapsulation efficiency was found to be 35 %, 81.17 %, 83.13 %, & 76.07 % and 46.27 %, 89.29 %, 84.91 %, & 77.60 % for vitamin D, E, B1 and B2 in micro and nano-sized starch, respectively. Fluorescence spectroscopy showed higher intensity for non-covalent interactions within the internal matrix of capsules. The FTIR peak at 877 cm-1 belonging to vitamin ring structures was prominent and confirmed the presence of vitamins in encapsulated powders. The nano starch capsules of vitamins showed better thermal stability with low crystallinity than micro starch capsules of vitamins. The study suggests the use of co-encapsulated vitamins in food fortification/supplementation to overcome the issues related to vitamin deficiencies.


Asunto(s)
Nanopartículas , Almidón , Almidón/química , Vitaminas , Colecalciferol , Nanopartículas/química , Vitamina A , Vitamina K
10.
RSC Adv ; 12(38): 24480-24490, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36128392

RESUMEN

Fast ionic conduction at low operating temperatures is a key factor for the high electrochemical performance of solid oxide fuel cells (SOFCs). Here an A-site deficient semiconductor electrolyte Sr1-x Co x FeO3-δ is proposed for low-temperature solid oxide fuel cells (LT-SOFCs). A fuel cell with a structure of Ni/NCAL-Sr0.7Co0.3FeO3-δ -NCAL/Ni reached a promising performance of 771 mW cm-2 at 550 °C. Moreover, appropriate doping of cobalt at the A-site resulted in enhanced charge carrier transportation yielding an ionic conductivity of >0.1 S cm-1 at 550 °C. A high OCV of 1.05 V confirmed that neither short-circuiting nor power loss occurred during the operation of the prepared SOFC device. A modified composition of Sr0.5Co0.5FeO3-δ and Sr0.3Co0.7FeO3-δ also reached good fuel cell performance of 542 and 345 mW cm-2, respectively. The energy bandgap analysis confirmed optimal cobalt doping into the A-site of the prepared perovskite structure improved the charge transportation effect. Moreover, XPS spectra showed how the Co-doping into the A-site enhanced O-vacancies, which improve the transport of oxide ions. The present work shows that Sr0.7Co0.3FeO3-δ is a promising electrolyte for LT-SOFCs. Its performance can be boosted with Co-doping to tune the energy band structure.

11.
ACS Appl Mater Interfaces ; 14(38): 43067-43084, 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36121444

RESUMEN

Achieving fast ionic conductivity in the electrolyte at low operating temperatures while maintaining the stable and high electrochemical performance of solid oxide fuel cells (SOFCs) is challenging. Herein, we propose a new type of electrolyte based on perovskite Sr0.5Pr0.5Fe0.4Ti0.6O3-δ for low-temperature SOFCs. The ionic conducting behavior of the electrolyte is modulated using Mg doping, and three different Sr0.5Pr0.5Fe0.4-xMgxTi0.6O3-δ (x = 0, 0.1, and 0.2) samples are prepared. The synthesized Sr0.5Pr0.5Fe0.2Mg0.2Ti0.6O3-δ (SPFMg0.2T) proved to be an optimal electrolyte material, exhibiting a high ionic conductivity of 0.133 S cm-1 along with an attractive fuel cell performance of 0.83 W cm-2 at 520 °C. We proved that a proper amount of Mg doping (20%) contributes to the creation of an adequate number of oxygen vacancies, which facilitates the fast transport of the oxide ions. Considering its rapid oxide ion transport, the prepared SPFMg0.2T presented heterostructure characteristics in the form of an insulating core and superionic conduction via surface layers. In addition, the effect of Mg doping is intensively investigated to tune the band structure for the transport of charged species. Meanwhile, the concept of energy band alignment is employed to interpret the working principle of the proposed electrolyte. Moreover, the density functional theory is utilized to determine the perovskite structures of SrTiO3-δ and Sr0.5Pr0.5Fe0.4-xMgxTi0.6O3-δ (x = 0, 0.1, and 0.2) and their electronic states. Further, the SPFMg0.2T with 20% Mg doping exhibited low dissociation energy, which ensures the fast and high ionic conduction in the electrolyte. Inclusively, Sr0.5Pr0.5Fe0.4Ti0.6O3-δ is a promising electrolyte for SOFCs, and its performance can be efficiently boosted via Mg doping to modulate the energy band structure.

12.
Chemphyschem ; 23(11): e202200314, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35657038

RESUMEN

The front cover artwork is provided by Prof. Faze Wang's group at the Southeast University. The built-in electric field created by the semiconductor heterostructure confines the proton transport on the surface layer of the nanocomposite core-shell heterostructure imparting faster ion transport and lower activation energy. Read the full text of the Research Article at 10.1002/cphc.202200170.

13.
Chemphyschem ; 23(11): e202200170, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35322910

RESUMEN

Lately, semiconductor-membrane fuel cells (SMFCs) have attained significant interest and great attention due to the deliverance of high performance at low operational temperatures, <550 °C. This work has synthesized the nanocomposite core-shell heterostructure (TiO2 -SrTiO3 ) electrolyte powder by employing the simple hydrothermal method for the SMFC. The SrTiO3 was grown in situ on the surface of TiO2 to form a core-shell structure. A heterojunction mechanism based on the energy band structure is proposed to explain the ion transport pathway and promoted protonic conductivity. The core-shell heterostructure (TiO2 -SrTiO3 ) was utilized as an electrolyte to reach the peak power density of 951 mW cm-2 with an open-circuit voltage of 1.075 V at 550 °C. The formation of core-shell heterostructure among TiO2 and SrTiO3 causes redistribution of charges and establishes a depletion region at the interface, which confined the protons' transport on the surface layer with accelerated ion transport and lower activation energy. The current work reveals novel insights to understand enhanced proton transport and unique methodology to develop low-temperature ceramic fuel cells with high performance.

14.
J Mater Sci Mater Med ; 33(1): 10, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35022850

RESUMEN

Herein we report synthesis of hematite (α-Fe2O3) nanorods by calcinating hydrothermally synthesized goethite nanorods at 5000C. The structural, optical and MRI imaging guided cancer therapeutic properties of fabricated nanorods have been discussed in this manscript. FESEM and TEM imaging techniques were used to confirm the nanorod like morphology of as prepared materials. As we know that Fe2O3 nanorods with size in the range of 25-30 nm exhibit super magnetism. After coating with the PEG, the as prepared nanorods can be used as T2 MR imaging contrast agents. An excellent T2 MRI contrast of 38.763 mM-1s-1 achieved which is highest reported so far for α-Fe2O3. Besides the as prepared nanorods display an excellent photothermal conversion efficiency of 39.5% thus acts as an excellent photothermal therapeutic agent. Thus, we envision the idea of testing our nanorods for photothermal therapy and MR imaging application both in vitro and in vivo, achieving an excellent T2 MRI contrast and photothermal therapy effect with as prepared PEGylated nanorods.


Asunto(s)
Compuestos Férricos/química , Nanotubos/química , Animales , Materiales Biocompatibles/química , Línea Celular , Supervivencia Celular , Femenino , Compuestos Férricos/toxicidad , Células HeLa , Humanos , Técnicas In Vitro , Imagen por Resonancia Magnética , Ensayo de Materiales , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Desnudos , Microscopía Electrónica de Rastreo , Nanotubos/toxicidad , Nanotubos/ultraestructura , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , Fototerapia/métodos , Polietilenglicoles/química , Espectrometría Raman , Difracción de Rayos X
15.
J Colloid Interface Sci ; 608(Pt 2): 1868-1881, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34752976

RESUMEN

Tunable microwave absorption characteristics are highly desirable for industrial applications such as antenna, absorber, and biomedical diagnostics. Here, we report BiNdxCrxFe1-2xO3 (x = 0, 0.05, 0.10, 0.15) nanoparticles (NPs) with electromagnetic matching, which exhibit tunable magneto-optical and feasible microwave absorption characteristics for microwave absorber applications. The experimental results and theoretical calculations demonstrate the original bismuth ferrite (BFO) crystal structure, while Nd and Cr injection in the BFO structure may cause to minimize dielectric losses and enhance magnetization by producing interfacial defects in the spinel structure. Nd and Cr co-doping plays a key role in ordering the BFO crystal structure, resulting in improved microwave absorption characteristics. The BiNd0.10Cr0.10Fe1.8O3 (BNCF2) sample exhibits a remarkable reflection loss (RL) of -37.7 dB with a 3-mm thickness in the 10.15 GHz-10.30 GHz frequency region. Therefore, Nd and Cr doping in BFO nanoparticles opens a new pathway to construct highly efficient BFO-based materials for tunable frequency, stealth, and microwave absorber applications.

16.
Environ Dev Sustain ; 23(6): 8774-8797, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32989376

RESUMEN

Due to fast and deadly spread of corona virus (COVID-19), the Government of India implemented lockdown in the entire country from 25 April 2020. So, we studied the differences in the air quality index (AQI) of Delhi (DTU, Okhla and Patparganj), Haryana (Jind, Palwal and Hisar) and Uttar Pradesh (Agra, Kanpur and Greater Noida) from 17 February 2020 to 4 May 2020. The AQI was calculated by combination of individual sub-indices of seven pollutants, namely PM2.5, PM10, NO2, NH3, SO2, CO and O3, collected from the Central Pollution Control Board website. The AQI has improved by up to 30-46.67% after lockdown. The AQI slope values - 1.87, - 1.70 and - 1.35 were reported for Delhi, - 1.11, - 1.31 and - 1.04 were observed for Haryana and - 1.48, - 1.79 and - 1.78 were found for Uttar Pradesh (UP), which may be attributed to limited access of transportation and industrial facilities due to lockdown. The ozone (O3) concentration was high at Delhi because of lesser greenery as compared to UP and Haryana, which provides higher atmospheric temperature favourable for O3 formation. The air mass back trajectory (AMBT) analysis reveals the contribution of air mass from Europe, Africa and Gulf countries as well as local emissions from Indo-Gangetic Plain, Madhya Pradesh and Maharashtra states of India.

17.
Poult Sci ; 99(8): R4101, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33044919

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The authors retract the above paper due to: 1) conflict of interest among the authors; and 2) addition of coauthor Dr. Muhammad Younus without his knowledge or permission. The authors apologize for these two grave mistakes.

18.
ACS Appl Mater Interfaces ; 12(31): 35071-35080, 2020 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-32667772

RESUMEN

Dual-ion electrolytes with oxygen ion and proton-conducting properties are among the innovative solid oxide electrolytes, which exhibit a low Ohmic resistance at temperatures below 550 °C. BaCo0.4Fe0.4Zr0.1Y0.1O3-δ with a perovskite-phase cathode has demonstrated efficient triple-charge conduction (H+/O2-/e-) in a high-performance low-temperature solid oxide fuel cell (LT-SOFC). Here, we designed another type of triple-charge conducting perovskite oxide based on Ba0.5Sr0.5Co0.1Fe0.7Zr0.1Y0.1O3-δ (BSCFZY), which formed a heterostructure with ionic conductor Ca0.04Ce0.80Sm0.16O2-δ (SCDC), showing both a high ionic conductivity of 0.22 S cm-1 and an excellent power output of 900 mW cm-2 in a hybrid-ion LT-SOFC. In addition to demonstrating that a heterostructure BSCFZY-SCDC can be a good functional electrolyte, the existence of hybrid H+/O2- conducting species in BSCFZY-SCDC was confirmed. The heterointerface formation between BSCFZY and SCDC can be explained by energy band alignment, which was verified through UV-vis spectroscopy and UV photoelectron spectroscopy (UPS). The interface may help in providing a pathway to enhance the ionic conductivities and to avoid short-circuiting. Various characterization techniques are used to probe the electrochemical and physical properties of the material containing dual-ion characteristics. The results indicate that the triple-charge conducting electrolyte is a potential candidate to further reduce the operating temperature of SOFC while simultaneously maintaining high performance.

19.
J Appl Microbiol ; 129(3): 474-485, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31800143

RESUMEN

Consumers' demand is increasing for safe foods without impairing the phytochemical and sensory quality. In turn, it has increased research interest in the exploration of innovative food processing technologies. Cold plasma technology is getting popularity now days owing to its high efficacy in decontamination of microbes in fruit and fruit-based products. As a on-thermal approach, plasma processing maintains the quality of fruits and minimizes the thermal effects on nutritional properties. Cold plasma is also exploited for inactivating enzymes and degrading pesticides as both are directly related with quality loss and presently are most important concerns in fresh produce industry. The present review covers the influence of cold plasma technology on reducing microbial risks and enhancing the quality attributes in fruits.


Asunto(s)
Contaminación de Alimentos/prevención & control , Calidad de los Alimentos , Frutas/química , Frutas/microbiología , Gases em Plasma/química , Manipulación de Alimentos , Inocuidad de los Alimentos , Plaguicidas/química
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