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1.
Molecules ; 28(9)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37175286

RESUMO

This work describes an ab initio principle computational examination of the optical, structural, elastic, electronic and mechanical characteristics of aluminum-based compounds AlRF3 (R = N, P) halide-perovskites. For optimization purposes, we used the Birch-Murnaghan equation of state and discovered that the compounds AlNF3 and AlPF3 are both structurally stable. The IRelast software was used to compute elastic constants (ECs) of the elastic properties. The aforementioned compounds are stable mechanically. They exhibit strong resistance to plastic strain, possess ductile nature and anisotropic behavior and are scratch-resistant. The modified Becke-Johnson (Tb-mBJ) approximation was adopted to compute various physical properties, revealing that AlNF3 and AlPF3 are both metals in nature. From the density of states, the support of various electronic states in the band structures are explained. Other various optical characteristics have been calculated from the investigations of the band gap energy of the aforementioned compounds. These compounds absorb a significant amount of energy at high levels. At low energy levels, the compound AlNF3 is transparent to incoming photons, whereas the compound AlPF3 is somewhat opaque. The examination of the visual details led us to the deduction that the compounds AlNF3 and AlPF3 may be used in making ultraviolet devices based on high frequency. This computational effort is being made for the first time in order to investigate the aforementioned properties of these chemicals, which have yet to be confirmed experimentally.

2.
Molecules ; 27(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36014503

RESUMO

This paper explains our first-principle computational investigation regarding the structural, optical, elastic, and electrical characteristics of gallium-based GaMF3 (M = Be and Ge) perovskite-type (halide-perovskite) compounds. Our current computation is based on density functional theory (DFT) and is achieved with the help of the WIEN2k code. We used the Birch-Murnaghan equation for optimization; in both compounds, we found that both GaBeF3 and GaGeF3 compounds are structurally stable. For the computation of elastic characteristics, the IRelast package for calculating elastic constants (ECs) is utilized. These compounds are mechanically ductile, scratch-resistant, anisotropic, and mechanically stable, showing huge opposition to plastic strain. The modified Becke-Johnson (TB-mBJ) potential approximation method is used to calculate different physical characteristics and shows that GaGeF3 behaves as a metal, whereas the GaBeF3 compound is insulating in nature. The involvement of various electronic states in band structures is calculated using the theory of the density of states. The different optical properties of these compounds can be studied easily using their band gap energy. At high energy ranges, these substances demonstrate strong absorption. At low energies, the GaGeF3 compound is transparent, while the GaBeF3 compound is opaque to incoming photons. Investigation of the optical characteristics has led us to the conclusion that both GaGeF3 and GaBeF3 compounds can be used for high-frequency ultraviolet device applications. This computational work is considered to be the first time that we can study these compounds, which to our knowledge have not previously been experimentally validated.

3.
Entropy (Basel) ; 21(8)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33267461

RESUMO

In this research article, the investigation of the three-dimensional Casson nanofluid flow in two rotating parallel plates has been presented. The nanofluid has been considered in steady state. The rotating plates have been considered porous. The heat equation is considered to study the magnetic field, joule heating, and viscous dissipation impacts. The nonlinear ordinary system of equations has been solved analytically and numerically. For skin friction and Nusslt number, numerical results are tabulated. It is found that velocity declines for higher values of magnetic and porosity parameter while it is heightened through squeezing parameter. Temperature is an enhancing function for Eckert number and nanoparticles volume fraction. Entropy generation is augmented with radiation parameter, Prandtl, and Eckert numbers. The Casson, porosity, magnetic field, and rotation parameters were reduced while the squeezing and suction parameters increased the velocity profile along x-direction. The porosity parameter increased the Bejan number while the Eckert and Prandtl numbers decreased the Bejan number. Skin friction was enhanced with increasing the Casson, porosity, and magnetic parameters while it decreased with enhancing rotation and squeezing parameters. All these impacts have been shown via graphs. The influences by fluid flow parameters over skin friction and Nusselt number are accessible through tables.

4.
Cureus ; 16(2): e54814, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38529435

RESUMO

One of the most uncommon cystic duct abnormalities is double cystic ducts exiting a single gallbladder. Adequate knowledge of this anomaly should be kept in mind to avoid any surgical complications. We present a case of a 49-year-old Asian Pakistani male patient who had an elective laparoscopic cholecystectomy and was discovered to have two distinct cystic ducts leaving the gallbladder. On examination, there were no other clinically relevant signs except for mild tenderness in the right hypochondrium. Ultrasound of the abdomen and pelvis confirmed the diagnosis of cholelithiasis. Standard four-port laparoscopic cholecystectomy was done via the open Hasson technique under general anesthesia. After meticulous dissection of the Calot's triangle, double cystic ducts were discovered draining a single gallbladder. The gallbladder was retrieved after clipping and cutting the cystic ducts and cystic artery. To minimize the risk of complications, surgeons must be aware of the numerous anatomical variations that may exist.

5.
ACS Omega ; 9(14): 16860-16867, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617604

RESUMO

The optoelectronic, structural, and elastic properties of K2ScCuCl6 and K2YCuCl6 double perovskite compounds were thoroughly investigated in this study using density functional theory. It is observed that both compounds exhibit exceptional structural and mechanical stability. The structural stability is assessed using Goldsmith's tolerance factor (tG), with values approaching unity indicating a reliable cubic perovskite structure. Phonon stability was ensured by the absence of negative energy formations and only real frequencies in the phonon calculations. Applying the finite displacement method also provided further evidence of the compounds' thermodynamic stability. The electronic properties analysis revealed that K2ScCuCl6 and K2YCuCl6 are narrow band gap semiconductors, with band gap values of 1.8 and 2.5 eV, respectively. This was confirmed by analyzing the density of states. Furthermore, the optical properties exhibited transparency at lower photon energies and significant absorption at higher energies. These exciting findings suggest that K2ScCuCl6 and K2YCuCl6 have promising applications in high-frequency UV devices.

6.
PLoS One ; 19(6): e0290915, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38843283

RESUMO

The Urdu language is spoken and written on different social media platforms like Twitter, WhatsApp, Facebook, and YouTube. However, due to the lack of Urdu Language Processing (ULP) libraries, it is quite challenging to identify threats from textual and sequential data on the social media provided in Urdu. Therefore, it is required to preprocess the Urdu data as efficiently as English by creating different stemming and data cleaning libraries for Urdu data. Different lexical and machine learning-based techniques are introduced in the literature, but all of these are limited to the unavailability of online Urdu vocabulary. This research has introduced Urdu language vocabulary, including a stop words list and a stemming dictionary to preprocess Urdu data as efficiently as English. This reduced the input size of the Urdu language sentences and removed redundant and noisy information. Finally, a deep sequential model based on Long Short-Term Memory (LSTM) units is trained on the efficiently preprocessed, evaluated, and tested. Our proposed methodology resulted in good prediction performance, i.e., an accuracy of 82%, which is greater than the existing methods.


Assuntos
Idioma , Processamento de Linguagem Natural , Humanos , Mídias Sociais , Aprendizado Profundo , Internet , Aprendizado de Máquina
7.
Cureus ; 16(1): e52686, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38384622

RESUMO

INTRODUCTION: Intestinal anastomosis is a surgical procedure crucial for restoring the integrity of the digestive system and finds widespread application in addressing diverse gastrointestinal disorders such as tumors, inflammatory conditions, and traumatic injuries. The timing of restarting feeding after the surgery is a debated topic due to its potential impact on patient recovery. Early enteral feeding, administered soon after surgery, aims to counteract the negative effects of prolonged fasting and improve outcomes. OBJECTIVE: This study analyzed the early and late enteral feeding following gastrointestinal anastomosis surgery. METHODS: Forty patients undergoing abdominal surgery were prospectively randomized into early or late feeding groups. Demographics, laboratory values, operative time, blood loss, transfusion rates, nasogastric tube (NGT) removal, hospital stay, gastrointestinal recovery, postoperative body mass index (BMI), and complications were compared. Data was organized in Excel and analyzed using the Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 27.0, Armonk, NY). Qualitative data were presented with numbers and percentages, while parametric quantitative data used means, standard deviations, and ranges. Non-parametric quantitative data were represented with medians and interquartile ranges. Chi-square tests were used for comparing two qualitative groups with predicted counts less than 5, while independent t-tests and Mann-Whitney tests were employed for comparing two quantitative groups with parametric and non-parametric distributions, respectively. The analysis used a 95% confidence interval, a 5% margin of error, and considered P values less than 0.05 as significant. RESULTS: Early feeding was associated with significantly shorter NGT removal times (p=0.005) and hospital stays (p=0.001) than late feeding. Postprandial potassium levels were higher in the early group (p=0.007), while CRP levels were significantly lower (p=0.004). No significant differences were found in operative time, blood loss, transfusion rates, gastrointestinal recovery, postoperative BMI, or complication rates between groups. CONCLUSIONS: Early enteral feeding appears safe and effective after gastrointestinal anastomosis surgery, potentially reducing hospital stay and improving inflammatory markers without increasing adverse events.

8.
Sci Rep ; 13(1): 17294, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828074

RESUMO

Customer churn, a phenomenon that causes large financial losses when customers leave a business, makes it difficult for modern organizations to retain customers. When dissatisfied customers find their present company's services inadequate, they frequently migrate to another service provider. Machine learning and deep learning (ML/DL) approaches have already been used to successfully identify customer churn. In some circumstances, however, ML/DL-based algorithms lacks in delivering promising results for detecting client churn. Previous research on estimating customer churn revealed unexpected forecasts when utilizing machine learning classifiers and traditional feature encoding methodologies. Deep neural networks were also used in these efforts to extract features without taking into account the sequence information. In view of these issues, the current study provides an effective method for predicting customer churn based on a hybrid deep learning model termed BiLSTM-CNN. The goal is to effectively estimate customer churn using benchmark data and increase the churn prediction process's accuracy. The experimental results show that when trained, tested, and validated on the benchmark dataset, the proposed BiLSTM-CNN model attained a remarkable accuracy of 81%.

9.
RSC Adv ; 13(41): 28395-28406, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37766934

RESUMO

In our pursuit of enhancing material performance, our focus is centered on the investigation of sodium-based halide perovskites, specifically NaXCl3 (where X = Be & Mg). We are utilizing first-principles methods based on density functional theory (DFT) to delve into these materials' properties and potential improvements. This investigation is executed using the WIEN2K code, aiming to uncover a deeper understanding of these materials' properties and potential enhancements. In this study, we utilize the Full Potential Linear Augmented Plane Wave (FP-LAPW) approach to analyze the structural, mechanical, electronic, and optical properties of cubic perovskite materials NaXCl3 (X = Be, Mg). We employ the Birch-Murnaghan fitting curve to assess the structural stability of these compounds, and in each case, the compound demonstrates structural stability in its optimal or ground state. The existence of real frequencies serves as confirmation of the phonon stability for both compounds. To determine the elastic characteristics, the IRelast Package is used. This involves calculating the elastic constants, which demonstrates that the compounds have anisotropic, ductile properties and demonstrate mechanical stability. We investigate the electronic properties by analyzing the density of states and the band structure. Both compounds exhibit an indirect band gap energy of 4.15 eV for NaBeCl3 and 4.16 eV for NaMgCl3. We analyze both the total and partial density of states to gain insight into the contributions of different electronic states to the band structure. Furthermore, optical characteristics, including the dielectric function, absorption coefficient, refractive index, and reflectivity, are investigated across an energy spectrum ranging from 0 to 15 eV. These findings can offer a comprehensive insight into the development of advanced electronic devices with improved efficiency and enhanced capabilities. Furthermore, they have the capacity to inspire experimental researchers to delve further into this field for subsequent explorations.

10.
Front Public Health ; 11: 1269209, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38106902

RESUMO

Introduction: The continually increasing incidence of hepatitis, a worldwide health issue, in Pakistan, has highlighted the need to investigate the epidemiology factors and implement preventive measures accordingly. The purpose of this study was to scrutinize the prevalent and significantly associated risk factors of hepatitis in students and employees, screening them for hepatitis B and C virus and vaccinating them against HBV to make IUB hepatitis free. Methodology: A total of 12,912 participants including students (n = 10,948) and employees (n = 1964) were screened for HBV and HCV via immunochromatographic test. Hepatitis- positive participants' blood samples were further tested and viral load was estimated by quantitative PCR. All the hepatitis-negative participants were vaccinated against HBV. The demographic and risk factors-related data were collected using the questionnaire. Statistical analysis (Chi-square test and bivariate regression analysis) was performed using SPSS software to explore any association between risk factors and hepatitis. Results: Results indicated that 662/12912 participants (students = 478/10,948, employees = 184/1,964) tested positive for hepatitis. Among them, HCV was observed to be more prevalent than HBV among the study participants, employees, and students, and viral count was low in both HBV and HCV-infected participants. However, men were more affected than women. The studied risk factors represented higher frequency among hepatitis-positive participants relative to the hepatitis-negative participants. The Chi-square test revealed that students' gender, history of hepatitis in the family and relatives, dental treatment, sharing cosmetics and shaving blades were significant (p > 0.005) risk factors of hepatitis while in the employees group surgery and age were significant. Moreover, the reused of syringes was found to be associated with hepatitis in both groups. The bivariate analysis helped to identify various new risk factors which were independently, either positively or negatively, associated with hepatitis. Discussion: Our study enabled us to recognize different risk factors of hepatitis among the target population. The information thus generated can be usefully applied in planning hepatitis awareness, targeted screening, and effective control programs for other target populations. In general, this module can be further utilized for any other disease.


Assuntos
Hepatite B , Hepatite C , Masculino , Humanos , Feminino , Vírus da Hepatite B , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Hepatite B/complicações , Fatores de Risco , Vacinação , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite C/prevenção & controle
11.
RSC Adv ; 13(20): 13735-13785, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37152571

RESUMO

Nanomaterials and nanoparticles are a burgeoning field of research and a rapidly expanding technology sector in a wide variety of application domains. Nanomaterials have made exponential progress due to their numerous uses in a variety of fields, particularly the advancement of engineering technology. Nanoparticles are divided into various groups based on the size, shape, and structural morphology of their bodies. The 21st century's defining feature of nanoparticles is their application in the design and production of semiconductor devices made of metals, metal oxides, carbon allotropes, and chalcogenides. For the researchers, these materials then opened a new door to a variety of applications, including energy storage, catalysis, and biosensors, as well as devices for conversion and medicinal uses. For chemical and thermal applications, ZnO is one of the most stable n-type semiconducting materials available. It is utilised in a wide range of products, from luminous materials to batteries, supercapacitors, solar cells to biomedical photocatalysis sensors, and it may be found in a number of forms, including pellets, nanoparticles, bulk crystals, and thin films. The distinctive physiochemical characteristics of semiconducting metal oxides are particularly responsible for this. ZnO nanostructures differ depending on the synthesis conditions, growth method, growth process, and substrate type. A number of distinct growth strategies for ZnO nanostructures, including chemical, physical, and biological methods, have been recorded. These nanostructures may be synthesized very simply at very low temperatures. This review focuses on and summarizes recent achievements in fabricating semiconductor devices based on nanostructured materials as 2D materials as well as rapidly developing hybrid structures. Apart from this, challenges and promising prospects in this research field are also discussed.

12.
RSC Adv ; 13(23): 15457-15466, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37275204

RESUMO

Herein, the optoelectronic, structural, thermoelectric, and elastic characteristics of M2LiCeF6 (M = Rb and Cs) double perovskite compounds were investigated using ab initio modeling in the DFT framework. The Birch-Murnaghan fitting curve used for the optimization showed that these two compounds are structurally stable. The elastic properties of the M2LiCeF6 (M = Rb and Cs) double perovskite compounds were examined using the IRelast code. The results showed that these two compounds possess mechanical stability, anisotropy, and toughness, and offer resistance to plastic deformation. The precise and accurate determination of their electronic properties was achieved via the Trans-Blaha-modified Becke-Johnson (TB-mBJ) approximation. The Rb2LiCeF6 and Cs2LiCeF6 compounds are narrow band gap semiconductors with band gaps of 0.6 eV and 0.8 eV at the high symmetrical points from (Γ-M), respectively, exhibiting an indirect nature. To further understand how the various states contribute to the different band structures, total and partial density of state (DOS) computations were performed. The optical properties in the energy range of 0-40 eV for Rb2LiCeF6 and Cs2LiCeF6 were explored. The selected materials show transparency in the low incident photon energy range and have large light absorption and transmission at higher photon energies. Thus, it can be concluded that Rb2LiCeF6 and Cs2LiCeF6 can be used in high-frequency UV devices based on their optical characteristics. Both materials exhibit high electrical conductivity, power factors, and figures of merit (ZT) and act as effective thermoelectric resources. To the best of our knowledge, this is the first theoretical research on the optoelectronic, structural, thermoelectric, and elastic features of M2LiCeF6 (M = Rb and Cs).

13.
RSC Adv ; 13(27): 18934-18945, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37350857

RESUMO

To enhance the effectiveness of materials, we are motivated to investigate lithium-based halide perovskites LiRCl3 (where R = Be and Mg) using first-principles techniques based on density functional theory (DFT), implemented in the WIEN2K code. In this study, the research makes use of the WIEN2K simulation code, employing the plane-wave and self-consistent (PWSCF) approach. The cut-off energy, responsible for distinguishing core and valence states, is established at -6.0 Ry. To guarantee well-converged solutions with 2000 K points, parameters of RMT × Kmax = 7.0 are selected, where RMT represents the smallest muffin-tin radius and Kmax denotes the plane wave cut-off. Convergence is determined to be attained when the overall energy of the system remains unchanged during self-consistent calculations, reaching a threshold of 0.001 Ry. We observe structural stability of these materials using the Birch-Murnaghan fit, tolerance factor and formation energy. The tolerance factor for LiMgCl3 and LiBeCl3 are 1.03 and 0.857, while the formation energy for LiMgCl3 and LiBeCl3 are -7.39 eV and -8.92 eV respectively, confirming these to be stable structurally. We evaluate the electronic properties of the current materials, shedding light on their nature, by using the suggested modified Becke-Johnson potential. It turns out that they are indirect insulators, with calculated band gaps of 4.02 and 4.07 eV for LiMgCl3 and LiBeCl3, respectively. For both materials, we also calculate the density of states (DOS), and our findings regarding the band gap energies are consistent with the band structure. It is observed that both materials exhibit transparency to low-energy photons, with absorption and optical conduction occurring in the UV range. These compounds are mechanically stable, according to the elastic investigation, however LiBeCl3 shows higher resistance to compressive and shear loads as well as resistance to shape change. On the other hand, LiMgCl3 exhibits weaker resistance to changes in volume. Furthermore, we discovered that none of the compounds are entirely isotropic, and specifically, LiMgCl3 and LiBeCl3 are brittle in nature. These materials appear to be potential candidates for use in optoelectronic devices based on our analysis of their optical properties. Our findings may provide comprehensive insight, invoking experimental studies for further investigations.

15.
Nanoscale ; 15(4): 1900-1913, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36607270

RESUMO

Electronic devices featuring biomimetic behaviour as electronic synapses and neurons have motivated the emergence of a new era in information and humanoid robotics technologies. In the human body, a nociceptor is a unique sensory neuron receptor that is capable of detecting harmful signals, leading to the central nervous system initiating a motor response. Herein, a nickel-doped zinc oxide (NZO)/Au based memristor is fabricated for the first time and characterized for artificial nociceptor application. For this, the introduction of a nickel-doped zinc oxide (NZO) layer between P++-Si and Au electrodes is used to eliminate the surface effects of the NZO layer, resulting in improved volatile threshold switching performance. Depending on the intensity, duration, and repetition rate of the external stimuli, this newly created memristor exhibits various critical nociceptive functions, including threshold, relaxation, allodynia, and hyperalgesia. The electron trapping/detrapping to/from the traps in the NZO layer is responsible for these nociceptive properties. This kind of NZO-based device produces a multifunctional nociceptor performance that is essential for applications in artificial intelligence systems, such as neural integrated devices with nanometer-sized features.


Assuntos
Óxido de Zinco , Humanos , Zinco , Inteligência Artificial , Níquel
16.
ACS Omega ; 8(20): 17779-17787, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37251136

RESUMO

In the present work, several properties of fluoroperovskites are computed and examined through the approximations of trans- and blaha-modified Becke-Johnson (TB-mBJ) and generalized gradient approximation of Perdew-Burke-Ernzerhof (GGA-PBE) integrated within density functional theory (DFT). The lattice parameters for cubic TlXF3 (X = Be, Sr) ternary fluoroperovskite compounds at an optimized state are examined and their values are used to calculate the fundamental physical properties. TlXF3 (X = Be and Sr) cubic fluoroperovskite compounds contain no inversion symmetry and are thus a non-centrosymmetric system. The phonon dispersion spectra confirm the thermodynamic stability of these compounds. The results of electronic properties clarify that both the compounds possess a 4.3 eV of indirect band gap from M-X for TlBeF3 and a direct band gap of 6.03 eV from X-X for TlSrF3, which display that both compounds are insulators. Furthermore, the dielectric function is considered to explore optical properties like reflectivity, refractive index, absorption coefficient, etc., and the different types of transitions between the bands were investigated by using the imaginary part of the dielectric function. Mechanically, the compounds of interest are computed to be stable and possess high bulk modulus values, and the ratio of "G/B" is higher than "1", which indicates the strong and ductile nature of the compound. Based on our computations for the selected materials, we deem an efficient application of these compounds in an industrial application, which will provide a reference for future work.

17.
Nano Lett ; 11(3): 1061-9, 2011 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-21306114

RESUMO

A thin film of Al(0.94)Ga(0.06)N embedded with Er(3+) ions is used as an optical temperature sensor to image the temperature profile around optically excited gold nanostructures of 40 nm gold nanoparticles and lithographically prepared gold nanodots. The sensor is calibrated to give the local temperature of a hot nanostructure by comparing the measured temperature change of a spherical 40 nm gold NP to the theoretical temperature change calculated from the absorption cross section. The calibration allows us to measure the temperature where a lithographically prepared gold nanodot melts, in agreement with the bulk melting point of gold, and the size of the nanodot, in agreement with SEM and AFM results. Also, we measure an enhancement in the Er(3+) photoluminescence due to an interaction of the NP and Er(3+). We use this enhancement to determine the laser intensity that melts the NP and find that there is a positive discontinuous temperature of 833 K. We use this discontinuous temperature to obtain an interface conductance of ∼10 MW/m(2)-K for the gold NP on our thermal sensor surface.


Assuntos
Nanopartículas , Calibragem , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Temperatura
18.
RSC Adv ; 12(12): 7002-7008, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35424649

RESUMO

In this research work, the Tl-based fluoroperovskite compounds TlLF3 (L = Ca, Cd) were investigated computationally using density functional theory (DFT) to comprehend their structural, elastic, optical, and electronic properties. Computation of the tolerance factor and Birch-Murnaghan curve indicated that the compounds are cubic and structurally stable. The structurally optimized lattice constants and the optimum volume corresponding to the optimum energy were measured. Elastic properties were predicted using the IRelast package, and the results showed that the compounds of interest are mechanically stable, ductile, and anisotropic in nature. The electronic properties (band structures and density of states) show that TlCaF3 and TlCdF3 possess a wide direct bandgap from (X-X) symmetry points of 5.7 eV and 5.6 eV, respectively. The contributions of different elemental states to the valence and conduction bands are evaluated from the total and partial density of states (TDOS & PDOS). Analysis of the optical properties showed that these compounds possess a high refractive index, absorption coefficient, and reflectivity at high energy ranges. The values of the direct bandgap indicated that these compounds are expected to be semiconducting in nature, and their use is primarily considered to be in the semiconductor industries and optoelectronic devices. These compounds are new and have been investigated for the first time using the computational approach, which provides comprehensive insight into their different properties; based on the results, they are recommended as industrial candidates.

19.
Materials (Basel) ; 15(17)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36079324

RESUMO

Al-based fluoroperovskites compounds AlMF3 (M = Cr, B) are investigated computationally and calculated their elastic, structural, optical, and electrical properties in this study utilising TB-MBJ potential (also GGA+U for AlCrF3) approximations, according to the Birch Murnaghan Equation curve and tolerance factor, these material are structurally cubic and stable. The IRelast algorithm is used to forecast elastic properties, and the outputs show that these compound are mechanically stable, anisotropic and ductile. AlBF3 has a metallic nature and overlapping states, while AlCrF3 have a narrow indirect band gap at (X-M) points of symmetry, with band gaps of 0.71 eV for AlCrF3 and zero eV for AlBF3. The partial and total density of states are being used to determine the influences of different basic states to the conduction and valence bands (TDOS & PDOS). Investigation of Optical properties shows that these compounds have low refractive index and high absorption coefficient, conductivity, reflective coefficient at high energy ranges. Owing to the indirect band gap, the applications of these compounds are deemed in conducting industries. Here we are using these compounds for first time and are examined using the computational method, which delivers a complete view into the different properties.

20.
RSC Adv ; 12(21): 13456-13463, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35527731

RESUMO

The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1-x Co x O (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1-x Co x O was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn't change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.

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