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1.
J Environ Manage ; 330: 117132, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584468

RESUMO

Herein, the ternary CdS/BiVO4/g-C3N4 (CBG) hybrid semiconductor photocatalyst was prepared via a hydrothermal technique. The synthesized photocatalysts were thoroughly characterized using powder XRD, XPS, FTIR, SEM, TEM, and UV-DRS to investigate the microstructural, morphological attributes, and optical properties. The photocatalytic activity of the ternary CBG hybrid semiconductor was assessed through the photodegradation of Methylene Blue (MB) aqueous dye under visible light. The outcomes exhibited that the CBG hybrid semiconductor showed excellent photocatalytic activity (about 94.5% after 120 min) compared to the results obtained with the pristine materials or the other composite (CdS/BiVO4). The enhancement of photocatalytic activity can be due to the construction of heterojunctions among g-C3N4, CdS, and BiVO4, which improves charge transfer efficiency and hence favors the degradation of organic dyes. Moreover, the as-prepared photocatalyst showed excellent stability after five cycles, indicating good stability and reusability. Subsequently, a possible photocatalytic mechanism was proposed based on the experimental results. The current investigation provides a promising strategy to promote photocatalytic activity to eliminate waterborne contaminants.


Assuntos
Azul de Metileno , Nanocompostos , Luz , Corantes
2.
J Environ Manage ; 330: 117134, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584459

RESUMO

Recently, the major environmental pollution produced by the release of wastewater in liquid type is one of the most extensive forms of foremost pollution in water ecosystems. In this article, the Bi2O3/g-C3N4 nanocomposite with a direct Z-scheme was effectively obtained by a facile hydrothermal system. The crystal structures, surface morphology, chemical composition, and the optical belongings of the as-obtained composite catalysts were examined by Power XRD, FT-IR spectra, High-resolution XPS spectra, FE-SEM images with EDX spectra, High-resolution TEM images, UV-Vis DRS, and PL spectra respectively. Furthermore, the photocatalytic performance was assessed by the degradation of aqueous Rhodamine B (Rh B) dye under visible-light exposure. The Bi2O3/g-C3N4 composite photocatalysts (PCs) showed the maximum photo-degradation efficiency through a rate constant value of 0.0149 min-1, which is 4.9 and 5.3 folds superior to Bi2O3, and GCN, respectively. The better GBO2 nanocomposite PCs showed a superior photocatalytic degradation performance (>82%) of aqueous Rh B dye after five successive recycles. Moreover, based on these outcomes of the radical scavenging test, a direct and effective Z-scheme photocatalytic charger transfer mechanism was also projected. Finally, the reusability of the as-obtained Bi2O3/g-C3N4 nanocomposite has better stability and reusability, which was a favourable applicant for wastewater handling.


Assuntos
Ecossistema , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Fontes de Energia Elétrica , Água
3.
Sensors (Basel) ; 21(17)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34502839

RESUMO

Advances in early insect detection have been reported using digital technologies through camera systems, sensor networks, and remote sensing coupled with machine learning (ML) modeling. However, up to date, there is no cost-effective system to monitor insect presence accurately and insect-plant interactions. This paper presents results on the implementation of near-infrared spectroscopy (NIR) and a low-cost electronic nose (e-nose) coupled with machine learning. Several artificial neural network (ANN) models were developed based on classification to detect the level of infestation and regression to predict insect numbers for both e-nose and NIR inputs, and plant physiological response based on e-nose to predict photosynthesis rate (A), transpiration (E) and stomatal conductance (gs). Results showed high accuracy for classification models ranging within 96.5-99.3% for NIR and between 94.2-99.2% using e-nose data as inputs. For regression models, high correlation coefficients were obtained for physiological parameters (gs, E and A) using e-nose data from all samples as inputs (R = 0.86) and R = 0.94 considering only control plants (no insect presence). Finally, R = 0.97 for NIR and R = 0.99 for e-nose data as inputs were obtained to predict number of insects. Performances for all models developed showed no signs of overfitting. In this paper, a field-based system using unmanned aerial vehicles with the e-nose as payload was proposed and described for deployment of ML models to aid growers in pest management practices.


Assuntos
Afídeos , Nariz Eletrônico , Animais , Insetos , Aprendizado de Máquina , Espectroscopia de Luz Próxima ao Infravermelho , Triticum
4.
Sensors (Basel) ; 20(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911709

RESUMO

Bushfires are increasing in number and intensity due to climate change. A newly developed low-cost electronic nose (e-nose) was tested on wines made from grapevines exposed to smoke in field trials. E-nose readings were obtained from wines from five experimental treatments: (i) low-density smoke exposure (LS), (ii) high-density smoke exposure (HS), (iii) high-density smoke exposure with in-canopy misting (HSM), and two controls: (iv) control (C; no smoke treatment) and (v) control with in-canopy misting (CM; no smoke treatment). These e-nose readings were used as inputs for machine learning algorithms to obtain a classification model, with treatments as targets and seven neurons, with 97% accuracy in the classification of 300 samples into treatments as targets (Model 1). Models 2 to 4 used 10 neurons, with 20 glycoconjugates and 10 volatile phenols as targets, measured: in berries one hour after smoke (Model 2; R = 0.98; R2 = 0.95; b = 0.97); in berries at harvest (Model 3; R = 0.99; R2 = 0.97; b = 0.96); in wines (Model 4; R = 0.99; R2 = 0.98; b = 0.98). Model 5 was based on the intensity of 12 wine descriptors determined via a consumer sensory test (Model 5; R = 0.98; R2 = 0.96; b = 0.97). These models could be used by winemakers to assess near real-time smoke contamination levels and to implement amelioration strategies to minimize smoke taint in wines following bushfires.


Assuntos
Nariz Eletrônico , Vitis , Vinho , Inteligência Artificial , Frutas/química , Fumaça/análise , Vinho/análise
5.
J Nanosci Nanotechnol ; 19(9): 5529-5545, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30961707

RESUMO

In this study, adsorption is an attractive for the removal of industrial dyes from aqueous simulated wastewaters is reported. The ternary graphene oxide-TiO2-SiO2 (GTS) nanocomposite was synthesized by sol-gel method. The as-synthesized nanocomposite was characterized by XRD, BET, FT-IR, SEM-EDAX and TEM analysis. It was found that the synthesised nanocomposite has excellent adsorption and photocatalytic degradation abilities for the removal of cationic dyes, methylene blue (MB) and crystal violet (CV) owing to its homogeneous mesoporosity with a BET surface area of 583.15 m²/g. Furthermore, the adsorption mechanism of these cationic dyes follows pseudosecond-order kinetic model. In addition, the GTS nanocomposite showed maximum adsorption efficiency over MB and CV around 384.62 mg/g and 188.68 mg/g respectively. The thermodynamic parameters (ΔG°, ΔH°, and ΔS°) calculated from the temperature dependent isotherms suggested that the adsorption was spontaneous and endothermic in nature. The study on the reusability of the GTS nanocomposite showed that, even after five succeeding cycles, the capacity of the adsorbent was almost identical.

6.
Bioorg Med Chem ; 24(22): 5988-6003, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27707628

RESUMO

Since our first discovery of a CD4-mimic, NBD-556, which targets the Phe43 cavity of HIV-1 gp120, we and other groups made considerable progress in designing new CD4-mimics with viral entry-antagonist property. In our continued effort to make further progress we have synthesized twenty five new analogs based on our earlier reported viral entry antagonist, NBD-11021. These compounds were tested first in HIV-1 Env-pseudovirus based single-cycle infection assay as well as in a multi-cycle infection assay. Four of these new compounds showed much improved antiviral potency as well as cytotoxicity. We selected two of the best compounds 45A (NBD-14009) and 46A (NBD-14010) to test against a panel of 51 Env-pseudotyped HIV-1 representing diverse subtypes of clinical isolates. These compounds showed noticeable breadth of antiviral potency with IC50 of as low as 150nM. These compounds also inhibited cell-to-cell fusion and cell-to-cell HIV-1 transmission. The study is expected to pave the way of designing more potent and selective HIV-1 entry inhibitors targeted to the Phe43 cavity of HIV-1 gp120.


Assuntos
Fármacos Anti-HIV/farmacologia , Desenho de Fármacos , HIV-1/efeitos dos fármacos , Pirróis/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Tiazóis/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , HIV-1/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
7.
J Food Sci Technol ; 51(4): 750-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24741170

RESUMO

To make more effective use of available marine resources, acid soluble collagen (ASC) was isolated from body and foot of wedge clam Donax cuneatus Linnaeus, 1758 with acetic acid and was characterized for their potential and commercial applications. The yield of ASC was 17% and 23% respectively. SDS PAGE, UV and FTIR spectroscopy showed that both were type I mainly with slight differences. HPLC was used for identifying the presence of different types of amino acids, where glycine was more or less 20% in both the samples and takes the lead amino acid position and presence of imino acids (11.8 and 12.6%) has been the characteristic feature of type I collagen.

8.
Sci Rep ; 14(1): 4504, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402262

RESUMO

Extended-range models are the interesting systems, which has been widely used to understand the non-local properties of the fermions at quantum scale. We aim to study the interplay between criticality and extended range couplings under various symmetry constraints. Here, we consider a two orbital Bernevig-Hughes-Zhang model in one dimension with longer (finite neighbor) and long-range (infinite neighbor) couplings. We study the behavior of model using scaling laws and universality class for models with Hermitian, parity-time ([Formula: see text]) symmetric and broken time-reversal symmetries. We observe the interesting results on multi-criticalities, where the universality class of critical exponent is different than the normal criticalities. Also, the results can be generalized by considering the interplay between criticalities and different symmetry classes of Hamiltonian. Also, with the introduction of extended-range of coupling, there occurs different criticalities, and we provide the analogy to characterize their universality classes. We also show the violation of Lorentz invariance at multi-criticalities and evaluation of short-range limit in long-range models as the highlights of this work.

9.
Nat Commun ; 15(1): 4042, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740739

RESUMO

Antennas that can operate across multiple communication standards have remained a challenge. To address these limitations, we propose a Field-Programmable Radio Frequency Surface (FPRFS), which is based on manipulating current flow on its surface to achieve desirable RF characteristics. In this work, we demonstrate that substantial enhancements in radiation efficiency can be achieved while preserving the high reconfigurability of antenna structures implemented on the FPRFS. This is accomplished by utilizing an asymmetric excitation, directing the excitation to the low-loss contiguous surface, and dynamically manipulating the imaged return current on a segmented ground plane by switches. This important insight allows for adaptable antenna performance that weakly depends on the number of RF switches or their loss. We experimentally validate that FPRFS antennas can achieve efficiencies comparable to traditionally implemented antenna counterparts. This permits the FPRFS to be effectively utilized as a productive antenna and impedance-matching network with real-time reconfigurability.

10.
Chemosphere ; 330: 138708, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37072085

RESUMO

Photocatalytic degradation of azo dyes is seen as a viable technique for addressing environmental and energy concerns simultaneously. Therefore, the primary requirement is the creation of a better catalyst with adequate product selectivity for removal efficiency under solar light. Herein, pure ZnO and Cu (0.10 M) doped cotton stalk activated carbons with ZnO (Cu-doped ZnO/CSAC) were produced, and these are labelled as CZ1, CZ2, CZ3, and CZ3/CSAC, respectively. The optoelectronic and photodegradation efficiencies were examined regarding the impact of doping and loading samples. The XRD patterns confirmed that the CZ3/CSAC sample exhibited a hexagonal wurtzite structure. The XPS survey confirmed that Cu ions were incorporated into the ZnO lattice in a Cu2+ oxidation state. The band gap value (CZ3/CSAC) was reduced (2.38 eV) compared to pure ZnO and CZ3. Moreover, PL and EIS analysis proved more efficient at separating photoinduced charged carriers for CZ3/CSAC than all other samples. The CZ3/CSAC sample showed improved photocatalytic degradation efficiency (93.09%) compared to the pure ZnO and CZ3 samples using brilliant green (BG) dye under sunlight irradiation.


Assuntos
Óxido de Zinco , Óxido de Zinco/química , Luz Solar , Metais , Fotólise , Corantes , Catálise
11.
Int J Biol Macromol ; 244: 125303, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37311516

RESUMO

The proposed research outlines a facile method to synthesize Silver Chromate/reduced graphene oxide nanocomposites (Ag2CrO4/rGO NCs) with a narrow dissemination size for the ecological treatment of hazardous organic dyes. The photodegradation performance toward the decontamination of model artificial methylene blue dye was assessed under solar light irradiation. The crystallinity, particle size, recombination of photogenerated charge carriers, energy gap and surface morphologies of synthesized nanocomposites were determined. The experiment objective is to use rGO nanocomposites to increase Ag2CrO4 photocatalytic efficiency in the solar spectrum. Tauc plots of ultraviolet-visible (UV-vis) spectrum were used to calculate the optical bandgap energy of the produced nanocomposites ∼1.52 eV, which resulted in a good photodegradation percentage of ∼92 % after 60 min irradiation of Solar light. At the same time, pure Ag2CrO4 and rGO nanomaterials showed ∼46 % and âˆ¼ 30 %, respectively. The ideal circumstances were discovered by investigating the effects of several parameters, including catalyst loading and different pH levels, on the degradation of dyes. However, the final composites maintain their ability to degrade for up to five cycles. According to the investigations, Ag2CrO4/rGO NCs are an effective photocatalyst and can be used as the ideal material to prevent water pollution. Furthermore, antibacterial efficacy for the hydrothermally synthesized nanocomposite was tested against gram-positive (+ve) bacteria viz. Staphylococcus aureus and gram-negative (-ve) bacteria viz. Escherichia coli. The maximum zone of inhibition for S. aureus and E. coli were 18.5 and 17 mm, respectively.


Assuntos
Antibacterianos , Nanocompostos , Antibacterianos/farmacologia , Antibacterianos/química , Esgotos , Escherichia coli , Staphylococcus aureus , Nanocompostos/química
12.
Sci Rep ; 13(1): 12121, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37495655

RESUMO

We investigate the nature of quantum criticality and topological phase transitions near the critical lines obtained for the extended Kitaev chain with next nearest neighbor hopping parameters and non-Hermitian chemical potential. We surprisingly find multiple gap-less points, the locations of which in the momentum space can change along the critical line unlike the Hermitian counterpart. The interesting simultaneous occurrences of vanishing and sign flipping behavior by real and imaginary components, respectively of the lowest excitation is observed near the topological phase transition. Introduction of non-Hermitian factor leads to an isolated critical point instead of a critical line and hence, reduced number of multi-critical points as compared to the Hermitian case. The critical exponents obtained for the multi-critical and critical points show a very distinct behavior from the Hermitian case.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38082593

RESUMO

Wireless endovascular sensors and stimulators are emerging biomedical technologies for applications such as endovascular pressure monitoring, hyperthermia, and neural stimulations. Recently, coil-shaped stents have been proposed for inductive power transfer to endovascular devices using the stent as a receiver. However, less work has been done on the external transmitter components, so the maximum power transferable remains unknown. In this work, we design and evaluate a wearable transmitter coil that allows 50 mW power transfer in simulation.Clinical Relevance-This allows more accurate measurements and precise control of endovascular devices.


Assuntos
Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Fontes de Energia Elétrica , Simulação por Computador , Stents
14.
Sci Rep ; 12(1): 11951, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831337

RESUMO

An attempt is made to find different emergent quantum phases for interacting topological state of quantum matter. Our study is based on the quantum field theoretical renormalization group (RG) calculations. The behaviour of the RG flow lines give the emergence of different quantum phases for non-interacting and interacting topological state of quantum matter. We show explicitly electron-electron interaction can turn a topologically trivial phase into a topologically nontrivial one and also topologically nontrivial phase to topologically trivial phase. We show that physics of emergence goes beyond the quantum Berezinskii-Kosterlitz-Thouless transition. We also present the analysis of fixed point and show the behaviour of fixed point changes in presence and absence of interaction. This work provides a new perspective not only from the topological state of interacting quantum matter and but also for the correlated quantum many -body physics.

15.
Mater Today Proc ; 56: 3780-3785, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36415847

RESUMO

Personnel protective equipment, N95 masks, and filtering facepiece respirators such as goggles, face shields, played a very important rolein the safety of bothvirus-affected persons and as well as medical staff, health workers. As the coronavirus (Covid-19) was increasing exponentially worldwide, healthcare has been the demand for this basic equipment especiallyface protection shields have critical issues. There has been an effort to find out the different ways to conserve PPE kits, to use after the sterilization process. The current work focused onthe fabrication of the Portable PPE Kit Sterilizer model using UV Ozone Sanitization Processto utilize for recycling of N95 masks, goggles. Due to its miniature structure, can be used in public health sectors like the hospital, research centers, schools, and laboratories also. The method adopted was cheap, reuse, well suited for mass sanitization.

16.
J Pharm Bioallied Sci ; 13(Suppl 2): S917-S920, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35017898

RESUMO

The commonly used prosthodontic materials are resins, ceramics, metals and silicones. A comprehensive review of literature was completed about the incorporation of nanomaterials in prosthetic dentistry using PubMed and Google Scholar databases. This was supplemented with a manual search of selected journals. English language articles in peer- reviewed journals were selected. Current literature reveals that incorporation of nanomaterials has significantly improved the properties of the prosthetic materials within the clinically acceptable ranges. There appears to be a need for a standardization for these in vitro studies carried out to evaluate their physical, mechanical and antimicrobial properties.

17.
Sci Rep ; 11(1): 1004, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441801

RESUMO

The investigation and characterization of topological quantum phase transition between gapless phases is one of the recent interest of research in topological states of matter. We consider transverse field Ising model with three spin interaction in one dimension and observe a topological transition between gapless phases on one of the critical lines of this model. We study the distinct nature of these gapless phases and show that they belong to different universality classes. The topological invariant number (winding number) characterize different topological phases for the different regime of parameter space. We observe the evidence of two multi-critical points, one is topologically trivial and the other one is topologically active. Topological quantum phase transition between the gapless phases on the critical line occurs through the non-trivial multi-critical point in the Lifshitz universality class. We calculate and analyze the behavior of Wannier state correlation function close to the multi-critical point and confirm the topological transition between gapless phases. We show the breakdown of Lorentz invariance at this multi-critical point through the energy dispersion analysis. We also show that the scaling theories and curvature function renormalization group can also be effectively used to understand the topological quantum phase transitions between gapless phases. The model Hamiltonian which we study is more applicable for the system with gapless excitations, where the conventional concept of topological quantum phase transition fails.

18.
Cureus ; 13(7): e16343, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34395125

RESUMO

Introduction  Coronavirus disease 2019 (COVID-19) resulted in postponing non-emergency elective surgeries beginning in April 2020. Our hospital successfully restarted elective orthopaedic surgery during the pandemic to help improve the quality of life of patients with chronic disabilities.  This study describes the development of local protocols and pathways to allow for a safe restart of elective orthopaedic surgery in a COVID-19-free 'green' site. It includes the morbidity and mortality outcomes of those patients who underwent non-emergency orthopaedic operations during this time.  Methods  This is a prospective cohort study over an eight-week period evaluating 104 patients undergoing non-emergency orthopaedic procedures through a COVID-19-free surgical pathway. The primary outcome measure was 14-day postoperative mortality. The main secondary outcome measures were the development of a COVID-19 infection in the hospital and 14 days postoperatively as well as the need for intensive care unit admissions.  Results  No patients developed a COVID-19 infection. There were no intensive care unit admissions or postoperative deaths during our study time frame. There was no statistical difference seen for age (< 70 or > 70), gender, body mass index, or American Society of Anesthesiologists (ASA) grades in the development of postoperative complications.  Conclusions  This study describes a roadmap to setting up a protocolised elective operating service for orthopaedic surgery. It has shown that standardised protocols in a COVID-19-free 'green' site, preoperative COVID-19 testing, and adherence to national guidelines on self-isolation can help prevent developing COVID-19 infection postoperatively and reduce the risk of postoperative mortality.

19.
Food Chem ; 343: 128544, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33223287

RESUMO

The changes in secondary structure of proteins with heating were characterised and compared for bovine masseter (fibre type I) and cutaneous trunci (fibre type II) muscles by Differential Scanning Calorimetry (DSC) and Fourier Transform InfraRed (FTIR) microspectroscopy. Heating led to a decrease in α- helices, and an increase in aggregated strands, random coils and aromatic side chains in the muscle fibres of both muscles. In the intramuscular connective tissue (IMCT) of both muscles, a decrease in α- helix, turn and unordered structures was complemented with an increase in aggregated strands. At temperatures < 60 °C, the greater thermal denaturation of proteins in cutaneous trunci than in masseter (FTIR), supported by a myosin associated peak at 55.8 °C for cutaneous trunci and no peak for masseter (DSC), indicates that myosin in type II fibres is more sensitive to thermal denaturation than myosin in type I fibres and this should be considered in thermal meat processing.


Assuntos
Varredura Diferencial de Calorimetria , Tecido Conjuntivo/química , Proteínas Musculares/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Animais , Bovinos , Carne , Proteínas Musculares/isolamento & purificação , Estrutura Secundária de Proteína
20.
Nanotechnology ; 20(47): 475604, 2009 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-19875877

RESUMO

An efficient method based on molecular beam epitaxy has been developed to integrate an epitaxial Ge quantum well buried into a single crystalline rare earth oxide. The monolithic heterostructure comprised of Gd2O3-Ge-Gd2O3 grown on an Si substrate exhibits excellent crystalline quality with atomically sharp interfaces. This heterostructure with unique structural quality could be used for novel nanoelectronic applications in quantum-effect devices such as nanoscale transistors with a high mobility channel, resonant tunneling diode/transistors, etc. A phenomenological model has been proposed to explain the epitaxial growth process of the Ge layer under oxide encapsulation using a solid source molecular beam epitaxy technique.

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