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1.
Anal Chem ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329825

RESUMO

Charge detection mass spectrometry (CD-MS) is a single-particle technique, where the masses of individual ions are determined from simultaneous measurements of their mass-to-charge ratio (m/z) and charge. The ions are trapped in an electrostatic linear ion trap (ELIT) and oscillate back and forth through a conducting cylinder connected to a charge-sensitive amplifier. The oscillating ions generate a periodic signal that is processed with fast Fourier transforms (FFTs) to obtain the oscillation frequency (which is related to m/z) and magnitude (which is proportional to the charge). The simultaneous trapping of two or more ions is a way to increase throughput. However, when multiple ions are trapped, it is possible that some of them have overlapping oscillation frequencies, which can lead to an error in the charge determination. To avoid this error, results from overlapping ions are usually discarded. When measurements are performed with many trapped ions, the most abundant m/z species are discarded at a higher rate, which affects the relative abundances in the mass distribution. Here, we report the development of a post-processing method called multiple ion charge extraction (MICE) that uses a statistical approach to assign charges to ions with overlapping frequencies. MICE recovers single-ion information from high signal measurements and makes the relative abundances more resilient to the signal intensity. This approach corrects for high signal m/z biasing, allowing analysis to be faster and more reliable. Using MICE, CD-MS measurements were made at rates of 120 ions/s with little m/z biasing.

2.
BMC Med Inform Decis Mak ; 24(1): 92, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38575951

RESUMO

Emerging from the convergence of digital twin technology and the metaverse, consumer health (MCH) is witnessing a transformative shift. The amalgamation of bioinformatics with healthcare Big Data has ushered in a new era of disease prediction models that harness comprehensive medical data, enabling the anticipation of illnesses even before the onset of symptoms. In this model, deep neural networks stand out because they improve accuracy remarkably by increasing network depth and making weight changes using gradient descent. Nonetheless, traditional methods face their own set of challenges, including the issues of gradient instability and slow training. In this case, the Broad Learning System (BLS) stands out as a good alternative. It gets around the problems with gradient descent and lets you quickly rebuild a model through incremental learning. One problem with BLS is that it has trouble extracting complex features from complex medical data. This makes it less useful in a wide range of healthcare situations. In response to these challenges, we introduce DAE-BLS, a novel hybrid model that marries Denoising AutoEncoder (DAE) noise reduction with the efficiency of BLS. This hybrid approach excels in robust feature extraction, particularly within the intricate and multifaceted world of medical data. Validation using diverse datasets yields impressive results, with accuracies reaching as high as 98.50%. DAE-BLS's ability to rapidly adapt through incremental learning holds great promise for accurate and agile disease prediction, especially within the complex and dynamic healthcare scenarios of today.


Assuntos
Big Data , Tecnologia , Humanos , Biologia Computacional , Instalações de Saúde , Redes Neurais de Computação
3.
J Environ Manage ; 360: 121086, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733841

RESUMO

This research focuses on the synthesis and application of a novel kaolin-supported g-C3N4/MoO3 nanocomposite for the degradation of tetracycline, an important antibiotic contaminant in water systems. The nanocomposite was prepared through a facile and environmentally friendly approach, leveraging the adsorption and photocatalytic properties of kaolin, g-C3N4 and MoO3 nanoparticles, respectively. Comprehensive characterization of the nanocomposite was conducted using techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and optical spectra. The surface parameters were studied using N2 adsorption-desorption isotherm. The elemental composition was studied using X-ray photoelectron spectroscopy. The efficiency of the developed nanocomposite in tetracycline degradation was evaluated and the results revealed an efficient tetracycline degradation exhibiting the synergistic effects of adsorption and photocatalytic degradation in the removal process. The tetracycline degradation was achieved in 60 min. Kinetic studies and thermodynamic analyses provided insights into the degradation mechanism, suggesting potential applications for the nanocomposite in wastewater treatment. Additionally, the recyclability and stability of the nanocomposite were investigated, demonstrating its potential for sustainable and long-term application in water treatment.


Assuntos
Caulim , Nanocompostos , Tetraciclina , Poluentes Químicos da Água , Purificação da Água , Tetraciclina/química , Nanocompostos/química , Adsorção , Purificação da Água/métodos , Caulim/química , Poluentes Químicos da Água/química , Catálise , Águas Residuárias/química , Difração de Raios X , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Pancreatology ; 23(6): 601-606, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37481340

RESUMO

BACKGROUND: /Objective: The extent of exocrine pancreatic insufficiency (EPI) in the paediatric population with acute pancreatitis (AP) is unknown. The primary objective was to use a 6 h stable-isotope breath test to determine the prevalence of EPI in children with AP. The secondary objective was to determine the diagnostic ability of a 4 h abbreviated breath test in the detection of EPI. METHODS: 13C-mixed triglyceride (MTG) breath test was used to measure fat digestibility in 12 children with AP and 12 normal children. EPI was diagnosed based on a cumulative dose percentage recovery (cPDR) cut-off value < 26.8% present in literature. To reduce the test burden, the diagnostic accuracy of an abbreviated 4 h test was evaluated, using a cPDR cut-off that was the 2.5th percentile of its distribution in control children. RESULTS: The cPDR of cases was significantly lower than that of controls (27.71 ± 7.88% vs 36.37 ± 4.70%, p = 0.005). The cPDR during acute illness was not significantly different to that at 1 month follow up (24.69 ± 6.83% vs 26.98 ± 11.10%, p = 0.52). The 4 h and 6 h breath test results correlated strongly (r = 0.93, p < 0.001) with each other. The new 4 h test had 87.5% sensitivity and 93.8% specificity for detecting EPI. CONCLUSION: Two-thirds (66.7%) of this sample of children with AP had EPI during admission, which persisted at 1 month follow up. The 4 h abbreviated 13C-MTG breath test has good diagnostic ability to detect EPI in children and may improve its clinical utility in this age group.


Assuntos
Insuficiência Pancreática Exócrina , Pancreatite , Humanos , Criança , Pancreatite/complicações , Pancreatite/diagnóstico , Doença Aguda , Testes Respiratórios , Insuficiência Pancreática Exócrina/diagnóstico , Triglicerídeos
5.
Appl Opt ; 62(19): 5325-5333, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707238

RESUMO

Radio over free space optics (RoFSO) is one of the potential technologies that can satisfy the requirements of 5G services in a smart city. However, as RoFSO is line-of-sight (LOS) communication, one of its limitations is the occurrence of a skip zone in the targeted areas. In this work, a reconfigurable intelligent surface (RIS) is proposed as the solution to overcome this connection difficulty, which prevents signal blocking by generating LOS connections. These RIS modules extend the communication channel coverage, making it more intelligent and controllable. The performance analysis based on outage probability, ergodic channel capacity, and bit error rate has been performed using heterodyne detection. Malaga distribution has been used to model atmospheric turbulence. The exact closed-form expressions of the probability density function and cumulative distribution function of the end-to-end signal-to-noise ratio are derived. Exploiting these derived statistics, system performance is investigated through the ergodic channel capacity, outage probability, and average bit error rate for M-ary quadrature amplitude modulation and two binary modulation schemes: non-coherent binary frequency-shift keying and coherent binary phase-shift keying. Numerical results are compared among different turbulence conditions, link lengths, and scattering errors. The results show that the proposed RIS-assisted RoFSO technology has the potential to be effective for 5G smart city applications.

6.
Pediatr Surg Int ; 39(1): 73, 2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36617341

RESUMO

PURPOSE: Foreign body (FB) ingestion in children has varied presentation. When unwitnessed, it poses therapeutic and diagnostic challenges especially in the presence of pre-existing anatomical pathology. We aim to analyze the clinical course, management, and outcome of children with impacted esophageal FBs. METHODS: Retrospective chart review (Jan 2000-Feb 2018) recruiting children with impacted esophageal FBs. FBs in cricopharynx and those that moved to stomach were excluded. Investigations/management were based on underlying anatomical pathology, duration of impaction, and difficult FBs. Clinical details, management, and outcomes were collated. RESULTS: Of 86 children, N1 = 31 had identifiable predisposing anatomic pathology and N2 = 55 had impactions in normal esophagus or difficult FBs. N1 group presented early (42 months), had recurrent impactions (1-6), and needed multiple dilatations (0-8) and longer follow-up (avg 35 months). Food matter was commonest impaction. Many had persistent symptoms. N2 group had commonly coin impactions and strictures developed in long standing or corrosive FBs. Most were asymptomatic. CONCLUSION: Abnormal esophageal anatomy predisposes to impaction with organic food bolus. Age of presentation is earlier with recurrent impactions requiring multiple dilatations/surgery and longer follow-up. Metallic FBs commonly impact in normal esophagus and are often innocuous. Atypical/multiple FBs may mirror an underlying psychiatric illness.


Assuntos
Esôfago , Corpos Estranhos , Criança , Humanos , Estudos Retrospectivos , Esôfago/diagnóstico por imagem , Esôfago/cirurgia , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/cirurgia , Estômago
7.
J Solid State Electrochem ; 27(1): 271-280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36373059

RESUMO

The growing demand for electricity has increased the interest of the researchers towards exploration of energy storing devices (ESDs). With the motif for developing electrochemical energy storage devices, this research work is focussed on the study of MoO3 nanoparticles and its doping with chromium as an efficient electrode material for energy storage applications. The nanoparticles were synthesized by hydrothermal method and were examined by powder X-ray diffraction, which determined the thermodynamically stable orthorhombic phase of MoO3, and their morphologies were examined using scanning electron microscopy displaying flake-like structures. The typical vibrational bands of Mo-O were identified from Infra-red and Raman spectral analysis. The ultra violet diffuse reflectance spectra revealed the decrease in optical band gap after doping with chromium. The temperature dependent AC and DC conductivities were enhanced on doping. Electrochemical behaviour of the nanoparticles was probed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) measurements and galvanostatic charge-discharge (GCD) analysis for which specific capacitance (C sp) value of 334 Fg-1 was achieved for Cr-doped MoO3 nanoparticles. The electrochemical performance of the sample was found to be increased after doping with Cr.

8.
Sensors (Basel) ; 23(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37050704

RESUMO

This Special Issue presents the latest research and developments in the field of optical and RF propagation sensing, propagation/effects/channel molding, advancements in applications, signal far-field measurements, theoretical/measurement methods for beam handling/processing, military applications, and next-generation network formations, amongst others [...].

9.
Int J Mol Sci ; 24(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37373219

RESUMO

In the present work, superparamagnetic adsorbents based on 3-aminopropyltrimethoxy silane (APTMS)-coated maghemite (γFe2O3@SiO2-NH2) and cobalt ferrite (CoFe2O4@SiO2-NH2) nanoparticles were prepared and characterized using transmission-electron microscopy (TEM/HRTEM/EDXS), Fourier-transform infrared spectroscopy (FTIR), specific surface-area measurements (BET), zeta potential (ζ) measurements, thermogravimetric analysis (TGA), and magnetometry (VSM). The adsorption of Dy3+, Tb3+, and Hg2+ ions onto adsorbent surfaces in model salt solutions was tested. The adsorption was evaluated in terms of adsorption efficiency (%), adsorption capacity (mg/g), and desorption efficiency (%) based on the results of inductively coupled plasma optical emission spectrometry (ICP-OES). Both adsorbents, γFe2O3@SiO2-NH2 and CoFe2O4@SiO2-NH2, showed high adsorption efficiency toward Dy3+, Tb3+, and Hg2+ ions, ranging from 83% to 98%, while the adsorption capacity reached the following values of Dy3+, Tb3+, and Hg2+, in descending order: Tb (4.7 mg/g) > Dy (4.0 mg/g) > Hg (2.1 mg/g) for γFe2O3@SiO2-NH2; and Tb (6.2 mg/g) > Dy (4.7 mg/g) > Hg (1.2 mg/g) for CoFe2O4@SiO2-NH2. The results of the desorption with 100% of the desorbed Dy3+, Tb3+, and Hg2+ ions in an acidic medium indicated the reusability of both adsorbents. A cytotoxicity assessment of the adsorbents on human-skeletal-muscle derived cells (SKMDCs), human fibroblasts, murine macrophage cells (RAW264.7), and human-umbilical-vein endothelial cells (HUVECs) was conducted. The survival, mortality, and hatching percentages of zebrafish embryos were monitored. All the nanoparticles showed no toxicity in the zebrafish embryos until 96 hpf, even at a high concentration of 500 mg/L.


Assuntos
Mercúrio , Poluentes Químicos da Água , Humanos , Animais , Camundongos , Peixe-Zebra , Dióxido de Silício/química , Células Endoteliais , Mercúrio/química , Íons , Nanopartículas Magnéticas de Óxido de Ferro , Adsorção , Cinética , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química
10.
BMC Nurs ; 22(1): 153, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147627

RESUMO

Despite the presence of numerous generic time management instruments, relatively few research articles have assessed the validity and reliability of time management skills specific for the nursing profession. This study aimed at developing and validating a time management scale for nurses.Method A self-administered questionnaire was administered to 715 nurses working in hospitals and clinics in the northern region of the West Bank, Palestine. The scale was examined through exploratory factor analysis, reliability measures, and correlations with other scales.Results The scale revealed a 3-factor structure 1) organization of nursing work 2) planning and goal setting and 3) coordination of nursing work. The scale demonstrated excellent psychometric properties.Conclusions The Nursing Time Management Scale (NTMS) is a valid and reliable measure that can be used in assessing time management skills of nurses and in evaluating interventions and training modules aiming at developing nurses' time management skills.

11.
BMC Nurs ; 22(1): 386, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848893

RESUMO

BACKGROUND: In today's companies, time management abilities have grown as a significant predictor of nurses' success. Organizations have simplified their internal operations and flattened their organizational structures in an effort to increase productivity and cut expenses. As a result, successful time management skills are particularly crucial for nurses in recently restructured healthcare organizations. This study aimed at exploring factors influencing time management skills among Palestinian nurses. METHODS: Cross-sectional quantitative study of all nurses (715) working in private and government hospitals and primary healthcare centers in north Palestine was conducted. Time management skills were measured on a continuous scale using the Nursing Time Management Scale (NTMS), Arabic version. The scale measures various aspects of time management including goal setting, planning, scheduling, and organizing activities. The relationship between time management skills and background variables was assessed using the multivariate linear regression. RESULTS: The average total score for NTMS scale was 63.39 out of a total score of 90. This score indicates relatively good time management skills among the respondents. The multivariate linear regression results showed that females obtained slightly lower scores than males, coefficient = -2.36, p = 0.043. Nurses in primary care centers had significantly higher scores than nurses who work at hospitals, coefficient = 4.47, p = 0.004. The type of healthcare organization emerged as a significant factor predicting time management skills. Nurses in private hospitals had worse time management skills than nurses in government hospitals, coefficient = -12.27, p < 0.001. Nurse supervisors had better time management skills than staff nurses, coefficient = 4.01, p = 0.023. Nurses working in non-teaching hospitals had worse time management skills than nurses in teaching hospitals, coefficient = - 3.86, p = 0.001. Nurses who did not attend a time management course had worse time management skills than nurses who attended time management course, coefficient = - 4.05, p = p < 0.001. CONCLUSIONS: Healthcare institutions should consider organizational and individual factors to improve the time management skills of their staff. Time management training interventions are proven and effective policies that are recommended to be adopted by all healthcare centers.

12.
Chin J Traumatol ; 26(2): 101-105, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35491374

RESUMO

PURPOSE: Various surgical modalities are available to treat Neer types 2 and 5 unstable fractures of lateral end clavicle but none of them are standardized. Arthroscopic fixation of the displaced lateral end clavicle fractures provides good short-term results but mid- to long-term outcomes are not available. The purpose of this study was to show the mid- to long-term radiological and functional outcomes of these fractures treated arthroscopically by a TightRope device, and to show the complications associated with this procedure. METHODS: A retrospective study was conducted over 2 years from January 2014 to December 2015 with a minimum 5-year follow-up. Active patients aged 18-50 years with acute (less than 3 weeks) displaced fracture of lateral end of the clavicle, with a minimum 5-year follow-up were included in the study. Patients with associated fractures of the proximal humerus, glenoid, scapula and acromioclavicular joint injuries were excluded from the study along with open fractures and neurovascular injuries. The outcomes were assessed by objective (complications and radiographic examination) and subjective criteria (quick disabilities of the arm, shoulder and hand score, the Constant-Murley score and the visual pain analogue scale). The data were analyzed by SPSS version 21.0. RESULTS: Totally, 42 patients were operated during the study period and 37 were available with a minimum 5-year follow-up. Thirty were male and 7 were female with a mean age of 29.5 years and a mean follow-up of 6.1 years. The mean quick disabilities of the arm, shoulder and hand score was 68.2 ± 4.6 preoperatively and 1.27 ± 2.32 at final follow-up (p < 0.001); the mean visual pain analogue scale score was 6.85 ± 2.2 preoperatively and 0.86 ± 1.60 at final follow-up (p < 0.001). The average Constant-Murley score was 93.38 ± 3.25 at the end of the follow-up. There were 2 fixation failures, with established non-union and 3 patients developed radiographic acromioclavicular joint arthritis. CONCLUSIONS: Arthroscopic TightRope fixation of displaced lateral end clavicular fractures provides good radiological and functional outcomes at mid- to long-term follow-up. With the low complication rates and high patient satisfaction, this technique can be considered as a primary option in the surgical treatment of these fractures.


Assuntos
Fraturas Ósseas , Fraturas Expostas , Humanos , Masculino , Feminino , Adulto , Seguimentos , Clavícula/cirurgia , Estudos Retrospectivos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fraturas Ósseas/complicações , Fixação Interna de Fraturas/métodos , Dor , Resultado do Tratamento
13.
Niger J Clin Pract ; 26(9): 1215-1225, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37794532

RESUMO

Dental implants are considered an ideal treatment for a missing single tooth. Immediate loading of implants can hasten the procedure, providing comfort to the patients. Recently, immediate loading of implants has gained much importance as it helps hasten the procedure and provides more comfort to patients. A previous systematic review published 5 years ago compared the success rates between immediate and conventional loading. There are several factors that influence the success rate of implants that were not discussed in detail in the previous review. Hence, the present systematic review is done to report differences in the outcomes from single implant restorations of missing teeth in the posterior region in patients who were subjected to immediate loading and conventional loading. A follow up for 1 year was done. Electronic databases of Medline, Scopus, and Web of Science were searched for publications in the English Language during May 2021. The search results yielded 306 articles, out of which 225 were excluded based on title and abstract screening. Screening of the remaining 81 full text articles yielded 14 original research articles that satisfied the predefined inclusion criteria. Meta analysis was not possible due to the heterogeneity of the data. The overall success rate of the immediate loading of a single implant is 94.31%. Implants in the maxillary region had a higher survival rate than those in the mandibular region. The age range between 18 and 80 years showed good prognosis and outcomes in older individuals. Good oral hygiene was emphasized for all patients to prevent any secondary conditions or delays in healing.


Assuntos
Anodontia , Implantes Dentários , Carga Imediata em Implante Dentário , Perda de Dente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Prótese Dentária Fixada por Implante , Carga Imediata em Implante Dentário/métodos , Perda de Dente/cirurgia
14.
Niger J Clin Pract ; 26(6): 666-673, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37470637

RESUMO

Background and Aim: Various methods to accelerate the orthodontic tooth movement have been used, among which corticotomy is considered to be the most common one. The suggested reasoning for such acceleration was the regional acceleratory phenomenon (RAP). Since the RAP is a property of both the hard and soft tissues, we designed a soft tissue flap procedure to compare the effects with the conventional corticotomy procedure. A split-mouth study was conducted where the two procedures were assessed in a single participant. Patients and Methods: The total sample size was calculated to be 40 with 20 participants in each group. The rate of tooth movement was the primary outcome measure, and the secondary outcomes were dentoalveolar changes, which were studied in both the conventional corticotomy and the flap-only procedure based on a cone-beam computed tomography (CBCT) wherein the alveolar bone density (BD) around canines, tipping, and rotational changes in canines, premolars, and molars were assessed. Results: Corticotomy resulted in greater canine angulation, lesser canine rotation and premolar rotation, and greater molar rotation compared with flap elevation, but these differences were statistically insignificant. Conclusion: Though the corticotomy resulted in higher BD, the differences were statistically insignificant. There was no significant difference in the rate of space closure assessed by the two techniques compared.


Assuntos
Boca , Técnicas de Movimentação Dentária , Humanos , Técnicas de Movimentação Dentária/métodos
15.
Nanotechnology ; 33(40)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35704978

RESUMO

Stretchable electrochromic devices (ECDs) were fabricated from electrospun PEDOT:PSS (poly(3, 4-ethylenedioxythiophene):polystyrene sulfonate) fibers. Stretchable and transparent electrodes with a sheet resistance of 1200 Ω sq-1were prepared by depositing the conductive fibers on elastomeric substrates that were prepared from polydimethylsiloxane. The conductive substrates replaced the ITO coated glass electrodes that are typically used in ECDs. The functioning device was prepared from a flexible chitosan electrolytic gel and a 4, 7-bis(4-diphenylaminophenyl)-2, 1, 3-benzothiaziazole (TPA-BZT-TPA) electrochrome that were deposited on the streatchable transparent electrodes. The assembled device could be stretched to 150% its original length and bent to a curvature of 0.1. The device could be operated and switched between its yellow (off) and blue (on) states while being stretched and bent with a maximum contrast ΔT ≈ 30% at 805 nm and a coloration efficiency of 168 cm2C-1. The stretchable device had an electrochromic contrast that was 30% greater than its counterpart that was prepared from conventional ITO-glass electrodes. The critical composition required for making devices truly stretchable was possible by evaluating the performance of five types of devices consisting of different layers.

16.
Environ Res ; 212(Pt B): 113295, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35452668

RESUMO

Metal nanoparticles furnished by the green synthesis approach have exhibited fascinating attributes owing to their biocompatibility with biomolecules, and their rapid environmentally friendly synthesis. On copper oxide (CuO) nanoparticles, a laser induced bio reduction work has been accomplish using Centella asiatica aqueous extract at room temperature is the pioneer in the field. This synthesis technique is easy, fruitful, eco-friendly, and counterfeit for the size-tunable synthesis of diverse shapes of stable copper nanoparticles. UV-visible spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), Energy - Dispersive X-ray Spectroscopy (EDX), X-ray diffraction (XRD) and photodegradation study have astounding properties of regulating the formation, crystalline nature, and morphology of an integrated specimen. Moreover, the obtained copper oxide nanoparticle has the tendency to decrease the absorbance maximum value of methylene blue because of the catalytic activity posed by these nanoparticles on the reduction of methylene blue by Centella asiatica. It has been studied and confirmed by UV-visible spectrophotometer, and it has been recognised as an electron relay effect.


Assuntos
Cobre , Nanopartículas Metálicas , Cobre/química , Lasers , Nanopartículas Metálicas/química , Azul de Metileno/química , Extratos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
17.
Environ Res ; 211: 112970, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35219632

RESUMO

Recently, researchers are concentrating on the synthesis of composite materials to enhance the efficiency of the materials in various applications. In this work, nickel vanadium oxide (NiV2O6) nanocomposite material is prepared via two methods and the prepared samples have been characterized with basic studies to analyse the effect of preparation method and the reaction time. The XRD studies reveal a polycrystalline growth in both the methods. The broad XRD peaks obtained for samples prepared via hydrothermal method suggests the size reduction and 1D nanostructure formation. The SEM analysis shows the formation of 1D structures in hydrothermal and 3D microsphere structures in solvothermal methods. The possible formation mechanism behind this formation has been discussed in this manuscript. The FTIR peaks in the fingerprint region confirm the formation and vibration of metal-oxygen bonds. The large optical bandgap values obtained from Tauc plot again confirms the formation of nanostructures of the synthesized samples. The photocatalytic activity of nickel vanadium oxide on methylene blue dye under halogen light were performed and, the recyclability of the sample is investigated. It was found from the photocatalytic spectrum that, the samples prepared from both the methods shows a degradation efficiency of more than 80% within 150 min. It was confirmed that the prepared NiV2O6 photocatalyst samples does not lose their degradation ability even after five cycles of repeated usage.


Assuntos
Nanocompostos , Níquel , Catálise , Nanocompostos/química , Óxidos , Solventes , Vanádio , Águas Residuárias
18.
Environ Res ; 214(Pt 1): 113804, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35830910

RESUMO

Photocatalysis is found to be one of the best suited processes that respond to the purification of water systems and the semiconductor nanomaterials are learned to be incredible materials which carry out the photocatalytic process as they readily decompose the pollutants effectively. In this present work, CdSe nanoparticles belonging to II-VI group semiconductor compounds were synthesized using a facile hydrothermal process with different precursor concentrations and were analysed for various characterization studies such as X-ray diffraction (XRD), Transmission electron microscopy (TEM), UV-vis absorption spectroscopy, Fourier transform infrared spectroscopy (FTIR) and Photoluminescence (PL) studies. The XRD study of the synthesized CdSe nanostructures revealed that the average crystallite size was ranging from 18.5 nm to 24 nm pointing out the increase in size with increase in molar concentrations. The morphological structure of synthesized CdSe samples exhibited urchin-like structure for a lower concentration with several rod-like projections appearing in diverse directions. These CdSe nano-urchins synthesized with lower concentrations are found suitable to carry out the process of photocatalytic activity. The process was carried out under visible light radiation for 180 min with aqueous solution of methylene blue (MB) as the ideal toxin to be degraded. The attained degradation efficiency was nearly 80% clearly displaying that the synthesized samples are good photocatalysts. By tuning the bandgap, through the optimization of the precursor concentrations, greater efficiency can be achieved in future.


Assuntos
Compostos de Cádmio , Compostos de Selênio , Catálise , Luz , Azul de Metileno
19.
Environ Res ; 213: 113595, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35688219

RESUMO

Semiconductor nanoparticles and nanocrystals have a great impact due to its contribution in the diverse fields including electronics, solar energy, biological imaging, and photonics. Among these semiconductor nanoparticles, cadmium selenide of II-VI group binary semiconductor nanoparticles were synthesized using solvothermal process for the different reaction temperatures. The XRD pattern of the synthesized samples confirms the crystalline nature of the samples and showed increase in its crystallite size with rise in temperature. The morphology of the samples was analysed with TEM images and found that the nanoparticles synthesized at different temperatures were varied in size and shape indicating the increase in the size of the particles with the raise in temperature. The optical properties of the samples pointed out that they exhibit a blue shift owing to quantum confinement. Photocatalytic activity was carried out for the synthesized samples under visible light radiation using methylene blue (MB) as a model pollutant and it proved to be a good photocatalyst achieving the efficiency of 75% which is promising for future application with good optimization. The efficiency could be increased when these semiconductor CdSe nanoparticles are doped with metal particles due to an increase in the absorption edge wavelength and a decrease in bandgap energy were reported in detail.


Assuntos
Compostos de Cádmio , Nanopartículas , Compostos de Selênio , Compostos de Cádmio/química , Catálise , Nanopartículas/química , Têxteis , Águas Residuárias
20.
Environ Res ; 203: 111880, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34400161

RESUMO

The present research work focuses on preparing 3D transition metal doped copper oxide nanostructures through sonication method and to investigate the effect of doping different transition metal into copper oxide (CuO) on the basic properties of CuO nanoparticles and, to study the photocatalytic behaviour of the doped CuO samples. The morphological studies performed with the help of SEM revealed the formation of flower like CuO 3D nanostructures for all the doped samples. The slight shift in the position of peaks in the x-ray diffraction (XRD) pattern confirms that doping has been successfully done into CuO. Also, the sharp diffraction peaks suggest the polycrystalline nature of the sample with monoclinic structure. The UV-vis absorption analysis reveals a bandgap of 2.26, 2.12 and 2.15 eV for the CuO samples doped with nickel, zinc, and iron respectively via Tauc plot. The photocatalytic performance of the samples tested through the degradation of methylene blue (MB) dye suggests that samples doped with Zn shows better degradation. Thus, it is evident that the morphology and the optical properties of the CuO can be tailored by doping transition metal into it.


Assuntos
Nanopartículas , Nanoestruturas , Catálise , Cobre , Luz , Azul de Metileno
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