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1.
ACS Omega ; 9(8): 9147-9160, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434879

RESUMO

In this study, lead-free BiM2+(Zn, Ca, Mg)Ti-BiFeO3 ceramics are fabricated under eco-friendly hydrothermal reaction conditions at 250 °C. XRD patterns show that all the synthesized compounds exhibit a phase coexistence of monoclinic and tetragonal perovskite-type structures with a morphotropic phase boundary at x = 0.4, with minimum impurity. The calculated average crystallite/grain size of the samples was close to 50 nm at full width at half-maximum of the main peak. The corresponding bonds of the constituent elements were observed by FTIR analysis, which further supports the formation of the local structure. EDS analyses detect all of the elements, their quantities, and compositional homogeneity. SEM data show agglomerated and nearly spherical morphology with an average particle size of about 128 nm. All synthesized ceramic powders revealed thermal stability with trivial mass loss up to investigated high temperatures (1000 οC). The dielectric constant reached its maximum at 38.7 MHz and finally remained constant after 80 MHz for all nanoceramics. Because of the complementary impact of different compositions, the most effective piezoelectric characteristics of d33 = 136 pCN-1, Pr = 8.6 pCN-1 cm-2, and kp = 11% at 30 °C were attained at x = 0.4 content for 0.4BiCaTi-0.6BiFeO3 ceramic. The measured magnetic hysteresis data (M-H curve) showed a weak ferromagnetic nature with the highest moment of ∼0.23 emu/g for 0.4BiCaTi-0.6BiFeO3, and other samples exhibited negligible ferromagnetic to diamagnetic transition. The optical response study shows that the 0.4BiMgTi-0.6BiFeO3 sample yielded the maximal transmittance (50%), whereas the 0.4BiCaTi-0.6BiFeO3 compound exhibited the highest refractive index. The calculated large band gap shows a high insulating or dielectric nature. Our findings demonstrate that the BiM2+Ti-BiFeO3 system, which was fabricated using a low-temperature hydrothermal technique, is an excellent lead-free piezoelectric and multiferroic nanoceramic.

2.
ACS Omega ; 8(25): 22466-22485, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37396227

RESUMO

CsSnI3 is considered to be a viable alternative to lead (Pb)-based perovskite solar cells (PSCs) due to its suitable optoelectronic properties. The photovoltaic (PV) potential of CsSnI3 has not yet been fully explored due to its inherent difficulties in realizing defect-free device construction owing to the nonoptimized alignment of the electron transport layer (ETL), hole transport layer (HTL), efficient device architecture, and stability issues. In this work, initially, the structural, optical, and electronic properties of the CsSnI3 perovskite absorber layer were evaluated using the CASTEP program within the framework of the density functional theory (DFT) approach. The band structure analysis revealed that CsSnI3 is a direct band gap semiconductor with a band gap of 0.95 eV, whose band edges are dominated by Sn 5s/5p electrons After performing the DFT analysis, we investigated the PV performance of a variety of CsSnI3-based solar cell configurations utilizing a one-dimensional solar cell capacitance simulator (SCAPS-1D) with different competent ETLs such as IGZO, WS2, CeO2, TiO2, ZnO, PCBM, and C60. Simulation results revealed that the device architecture comprising ITO/ETL/CsSnI3/CuI/Au exhibited better photoconversion efficiency among more than 70 different configurations. The effect of the variation in the absorber, ETL, and HTL thickness on PV performance was analyzed for the above-mentioned configuration thoroughly. Additionally, the impact of series and shunt resistance, operating temperature, capacitance, Mott-Schottky, generation, and recombination rate on the six superior configurations were evaluated. The J-V characteristics and the quantum efficiency plots for these devices are systematically investigated for in-depth analysis. Consequently, this extensive simulation with validation results established the true potential of CsSnI3 absorber with suitable ETLs including ZnO, IGZO, WS2, PCBM, CeO2, and C60 ETLs and CuI as HTL, paving a constructive research path for the photovoltaic industry to fabricate cost-effective, high-efficiency, and nontoxic CsSnI3 PSCs.

3.
Sci Rep ; 13(1): 2521, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781884

RESUMO

Cesium tin chloride (CsSnCl3) is a potential and competitive absorber material for lead-free perovskite solar cells (PSCs). The full potential of CsSnCl3 not yet been realized owing to the possible challenges of defect-free device fabrication, non-optimized alignment of the electron transport layer (ETL), hole transport layer (HTL), and the favorable device configuration. In this work, we proposed several CsSnCl3-based solar cell (SC) configurations using one dimensional solar cell capacitance simulator (SCAPS-1D) with different competent ETLs like indium-gallium-zinc-oxide (IGZO), tin-dioxide (SnO2), tungsten disulfide (WS2), ceric dioxide (CeO2), titanium dioxide (TiO2), zinc oxide (ZnO), C60, PCBM, and HTLs of cuprous oxide (Cu2O), cupric oxide (CuO), nickel oxide (NiO), vanadium oxide (V2O5), copper iodide (CuI), CuSCN, CuSbS2, Spiro MeOTAD, CBTS, CFTS, P3HT, PEDOT:PSS. Simulation results revealed that ZnO, TiO2, IGZO, WS2, PCBM, and C60 ETLs-based halide perovskites with ITO/ETLs/CsSnCl3/CBTS/Au heterostructure exhibited outstanding photoconversion efficiency retaining nearest photovoltaic parameters values among 96 different configurations. Further, for the six best-performing configurations, the effect of the CsSnCl3 absorber and ETL thickness, series and shunt resistance, working temperature, impact of capacitance, Mott-Schottky, generation and recombination rate, current-voltage properties, and quantum efficiency on performance were assessed. We found that ETLs like TiO2, ZnO, and IGZO, with CBTS HTL can act as outstanding materials for the fabrication of CsSnCl3-based high efficiency (η ≥ 22%) heterojunction SCs with ITO/ETL/CsSnCl3/CBTS/Au structure. The simulation results obtained by the SCAPS-1D for the best six CsSnCl3-perovskites SC configurations were compared by the wxAMPS (widget provided analysis of microelectronic and photonic structures) tool for further validation. Furthermore, the structural, optical and electronic properties along with electron charge density, and Fermi surface of the CsSnCl3 perovskite absorber layer were computed and analyzed using first-principle calculations based on density functional theory. Thus, this in-depth simulation paves a constructive research avenue to fabricate cost-effective, high-efficiency, and lead-free CsSnCl3 perovskite-based high-performance SCs for a lead-free green and pollution-free environment.

4.
RSC Adv ; 12(54): 34850-34873, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36540224

RESUMO

In this study, combined DFT, SCAPS-1D, and wxAMPS frameworks are used to investigate the optimized designs of Cs2BiAgI6 double perovskite-based solar cells. First-principles calculations are employed to investigate the structural stability, optical responses, and electronic contribution of the constituent elements in Cs2BiAgI6 absorber material, where SCAPS-1D and wxAMPS simulators are used to scrutinize different configurations of Cs2BiAgI6 solar cells. Here, PCBM, ZnO, TiO2, C60, IGZO, SnO2, WS2, and CeO2 are used as ETL, and Cu2O, CuSCN, CuSbS2, NiO, P3HT, PEDOT:PSS, spiro-MeOTAD, CuI, CuO, V2O5, CBTS, CFTS are used as HTL, and Au is used as a back contact. About ninety-six combinations of Cs2BiAgI6-based solar cell structures are investigated, in which eight sets of solar cell structures are identified as the most efficient structures. Besides, holistic investigation on the effect of different factors such as the thickness of different layers, series and shunt resistances, temperature, capacitance, Mott-Schottky and generation-recombination rates, and J-V (current-voltage density) and QE (quantum efficiency) characteristics is performed. The results show CBTS as the best HTL for Cs2BiAgI6 with all eight ETLs used in this work, resulting in a power conversion efficiency (PCE) of 19.99%, 21.55%, 21.59%, 17.47%, 20.42%, 21.52%, 14.44%, 21.43% with PCBM, TiO2, ZnO, C60, IGZO, SnO2, CeO2, WS2, respectively. The proposed strategy may pave the way for further design optimization of lead-free double perovskite solar cells.

5.
Nanomaterials (Basel) ; 12(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36296771

RESUMO

In the future, when fossil fuels are exhausted, alternative energy sources will be essential for everyday needs. Hydrogen-based energy can play a vital role in this aspect. This energy is green, clean, and renewable. Electrochemical hydrogen devices have been used extensively in nuclear power plants to manage hydrogen-based renewable fuel. Doped zirconate materials are commonly used as an electrolyte in these electrochemical devices. These materials have excellent physical stability and high proton transport numbers, which make them suitable for multiple applications. Doping enhances the physical and electronic properties of zirconate materials and makes them ideal for practical applications. This review highlights the applications of zirconate-based proton-conducting materials in electrochemical cells, particularly in tritium monitors, tritium recovery, hydrogen sensors, and hydrogen pump systems. The central section of this review summarizes recent investigations and provides a comprehensive insight into the various doping schemes, experimental setup, instrumentation, optimum operating conditions, morphology, composition, and performance of zirconate electrolyte materials. In addition, different challenges that are hindering zirconate materials from achieving their full potential in electrochemical hydrogen devices are discussed. Finally, this paper lays out a few pathways for aspirants who wish to undertake research in this field.

6.
ACS Appl Bio Mater ; 5(3): 971-1012, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35226465

RESUMO

Traditional treatment approaches for cancer involve intravenous chemotherapy or other forms of drug delivery. These therapeutic measures suffer from several limitations such as nonspecific targeting, poor biodistribution, and buildup of drug resistances. However, significant technological advancements have been made in terms of superior modes of drug delivery over the last few decades. Technical capability in analyzing the molecular mechanisms of tumor biology, nanotechnology─particularly the development of biocompatible nanoparticles, surface modification techniques, microelectronics, and material sciences─has increased. As a result, a significant number of nanostructured carriers that can deliver drugs to specific cancerous sites with high efficiency have been developed. This particular maneuver that enables the introduction of a therapeutic nanostructured substance in the body by controlling the rate, time, and place is defined as the nanostructured drug delivery system (NDDS). Because of their versatility and ability to incorporate features such as specific targeting, water solubility, stability, biocompatibility, degradability, and ability to reverse drug resistance, they have attracted the interest of the scientific community, in general, and nanotechnologists as well as biomedical scientists. To keep pace with the rapid advancement of nanotechnology, specific technical aspects of the recent NDDSs and their prospects need to be reported coherently. To address these ongoing issues, this review article provides an overview of different NDDSs such as lipids, polymers, and inorganic nanoparticles. In addition, this review also reports the challenges of current NDDSs and points out the prospective research directions of these nanocarriers. From our focused review, we conclude that still now the most advanced and potent field of application for NDDSs is lipid-based, while other significantly potential fields include polymer-based and inorganic NDDSs. However, despite the promises, challenges remain in practical implementations of such NDDSs in terms of dosage and stability, and caution should be exercised regarding biocompatibility of materials. Considering these aspects objectively, this review on NDDSs will be particularly of interest for small-to-large scale industrial researchers and academicians with expertise in drug delivery, cancer research, and nanotechnology.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/uso terapêutico , Neoplasias/tratamento farmacológico , Estudos Prospectivos , Distribuição Tecidual
7.
Rev Sci Instrum ; 92(2): 023506, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648119

RESUMO

The Toroidal Magnetized System device has been significantly upgraded to enable development of various wall conditioning techniques, including methods based on ion and electron cyclotron (IC/EC) range of frequency plasmas, and to complement plasma-wall interaction research in tokamaks and stellarators. The toroidal magnetic field generated by 16 coils can reach its maximum of 125 mT on the toroidal axis. The EC system is operated at 2.45 GHz with up to 6 kW forward power. The IC system can couple up to 6 kW in the frequency range of 10 MHz-50 MHz. The direct current glow discharge system is based on a graphite anode with a maximum voltage of 1.5 kV and a current of 6 A. A load-lock system with a vertical manipulator allows exposure of material samples. A number of diagnostics have been installed: single- and triple-pin Langmuir probes for radial plasma profiles, a time-of-flight neutral particle analyzer capable of detecting neutrals in the energy range of 10 eV-1000 eV, and a quadrupole mass spectrometer and video systems for plasma imaging. The majority of systems and diagnostics are controlled by the Siemens SIMATIC S7 system, which also provides safety interlocks.

8.
Cult Med Psychiatry ; 41(3): 382-406, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28132396

RESUMO

To assess how participants receiving abnormal prenatal genetic testing results seek information and understand the implications of results, 27 US female patients and 12 of their male partners receiving positive prenatal microarray testing results completed semi-structured phone interviews. These interviews documented participant experiences with chromosomal microarray testing, understanding of and emotional response to receiving results, factors affecting decision-making about testing and pregnancy termination, and psychosocial needs throughout the testing process. Interview data were analyzed using a modified grounded theory approach. In the absence of certainty about the implications of results, understanding of results is shaped by biomedical expert knowledge (BEK) and cultural expert knowledge (CEK). When there is a dearth of BEK, as in the case of receiving results of uncertain significance, participants rely on CEK, including religious/spiritual beliefs, "gut instinct," embodied knowledge, and social network informants. CEK is a powerful platform to guide understanding of prenatal genetic testing results. The utility of culturally situated expert knowledge during testing uncertainty emphasizes that decision-making occurs within discourses beyond the biomedical domain. These forms of "knowing" may be integrated into clinical consideration of efficacious patient assessment and counseling.


Assuntos
Tomada de Decisões , Testes Genéticos , Conhecimentos, Atitudes e Prática em Saúde , Diagnóstico Pré-Natal/psicologia , Adulto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Gravidez , Estados Unidos , Adulto Jovem
9.
Mymensingh Med J ; 24(1): 1-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25725661

RESUMO

Farming is a large and main industry in Bangladesh. Large numbers of people are directly involved in farming and have very unique exposure compare to other sectors. Musculoskeletal problems among farmer population are not infrequent. This study was carried out among 200 farmers in one selected district. The study revealed that musculoskeletal problems were common among the farmers working in a traditional way. All the respondents were male. The age of all respondents lie between 20-60 years. Among them 22.5% farmers were illiterate, about 45.5% below Class V. About half (42%) of the respondents had reported pain in different parts of the body at least one or more times during working in land. And about two third (65.5%) of the farmers had history of joint pain and stiffness in last 12 month. Most of the farmers who suffered from musculoskeletal symptoms were 41-60 years. Specially who worked more then 20 years (82.6%) and average 6 hours per day (66.7%). The occurrence of musculoskeletal problems in various part of the body included Knee pain - 48.1%, Back pain (back ache) - 22.9%, Waist pain (low back ache) - 13.3%, Neck pain - 18.3% and shoulder pain - 10.7%. Length of work in year and daily average working hours were found significant association with musculoskeletal pain. It was found that musculoskeletal pain were more common among the farmers when they worked in squatting position (52%) and specially during weeding of plants (31%). Among them only 22% also engaged in other business. Most of the farmers complained dull aching pain (40.6%), only 2.3% noticed severe acute pain, but about 86% farmers' temporary stop their work for pain and 80% get relief after discontinue of work. About 75% respondents visited doctors for their pain which was statistically significant (p=0.001). It was found that the rates of musculoskeletal complaints are more among those individuals who worked relatively bad ergonomic condition, such as body position probably play an important role.


Assuntos
Doenças dos Trabalhadores Agrícolas/epidemiologia , Doenças Musculoesqueléticas/epidemiologia , Adulto , Bangladesh/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Mymensingh Med J ; 21(4): 627-32, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23134909

RESUMO

Climate change is taking its toll in the form of saline water intrusion into the mainland of Bangladesh, which is one of the lowest-altitude countries in the world. The study was carried out with the objective to assess the blood pressure status associated with salinity in saline prone selected areas of Bagherhat and Tangail districts from March 2008 - June 2008 of rural Bangladesh. Two hundred and ninety subjects were selected purposively from both the districts. About 70% of the respondents were males and below forty years of age. More than two thirds of the respondents were illiterate; belong to 4-5 member family, with monthly family income of less than Tk. 4000 per month. Only one third of the respondents were smokers. More than two thirds of the respondents from salinity area had salinity level of 2-3%. Among them majority were drinking saline water for 6-10 years and 26% were drinking for more than ten years. About 20% of the non saline respondents' systolic blood pressure was 110-120 mm of Hg and 26% of saline area had systolic blood pressure >135-140 mm of Hg. Mean systolic BP among salinity area was more than that for non salinity area. About 19% of the non saline respondents' diastolic blood pressure was ≤ 85 mm of Hg. About one third had ≥ 90 mm of Hg, among them 31% were from saline area. Mean diastolic BP among salinity area was more than non salinity area. There was no history of heart disease, and less than 1% was diabetic among them. About two thirds had mean arterial pressure <70 mm of Hg, among them majority were from non saline area. About one third had >70 mm of Hg, among them majority were from saline area. The study concluded that systolic and diastolic blood pressures of saline group were significantly higher than that of the non saline group.


Assuntos
Pressão Sanguínea , Cloreto de Sódio/análise , Abastecimento de Água/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Hosp Community Psychiatry ; 40(7): 724-31, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2777229

RESUMO

The functioning of 58 adolescent psychiatric patients at hospital admission, discharge, and one-and-a-half-year follow-up was examined in relation to six predictor variables: level of precipitating stress, primary process thinking on the Rorschach test, cognitive inefficiency, severity of psychopathology, maladaptive behavior on the unit, and process versus reactive illness. Severity of psychopathology and cognitive inefficiency were significantly related to the adolescents' functioning at all three observation points. High precipitating stress and short duration of symptoms (that is, in reactive illnesses) were associated with significantly better functioning at follow-up. Primary process thinking on the Rorschach was correlated with severe disturbances on admission, but was unrelated to outcome at discharge or follow-up. Maladaptive behavior on the unit was unrelated to functioning at any time. The authors concluded that outcome for hospitalized adolescents is determined by key patient differences and is systematically predictable.


Assuntos
Transtornos Mentais/reabilitação , Alta do Paciente , Adaptação Psicológica , Adolescente , Feminino , Seguimentos , Hospitais com 100 a 299 Leitos , Hospitais Psiquiátricos , Humanos , Masculino , Transtornos Mentais/psicologia , Pennsylvania , Escalas de Graduação Psiquiátrica , Meio Social
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