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1.
ACS Omega ; 9(4): 5068-5079, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313529

RESUMO

Zn-Fe layered double hydroxide (LDH) was synthesized through the low-temperature-based coprecipitation method. Various concentrations of Ag (1, 3, and 5 wt %) with a fixed amount (5 wt %) of polyvinylpyrrolidone (PVP) were doped into LDH nanocomposites. This research aims to improve the bactericidal properties and catalytic activities of doping-dependent nanocomposites. Adding Ag and PVP to LDH enhanced oxygen vacancies, which increased the amount of hydroxide adsorption sites and the number of active sites. The doped LDH was employed to degrade rhodamine-B dye in the presence of a reducing agent (NaBH4), and the obtained results showed maximum dye degradation in a basic medium compared to acidic and neutral. The bactericidal efficacy of doped Zn-Fe (5 wt %) showed a considerably greater inhibition zone of 3.65 mm against Gram-negative (G-ve) or Escherichia coli (E. coli). Furthermore, molecular docking was used to decipher the mystery behind the microbicidal action of Ag-doped PVP/Zn-Fe LDH and to propose an inhibition mechanism of ß-ketoacyl-acyl carrier protein synthase IIE. coli (FabH) and deoxyribonucleic acid gyrase E. coli behind in vitro results.

2.
Materials (Basel) ; 15(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36431535

RESUMO

Zinc sulfide (ZnS) thin films with variable structural, optical, electrical, and thermoelectric properties were obtained by changing the source-to-substrate (SSD) distance in the physical-vapor-thermal-coating (PVTC) system. The films crystallized into a zinc-blende cubic structure with (111) preferred orientation. The films had a wide 3.54 eV optical band gap. High-quality homogenous thin films were obtained at 60 mm SSD. The sheet resistance and resistivity of the films decreased from 1011 to 1010 Ω/Sq. and from 106 to 105 Ω-cm, when SSD was increased from 20 mm to 60 mm, respectively. The phase and band gap were also verified by first principles that were in agreement with the experimental results. Thermoelectric characteristics were studied by using the semi-classical Boltzmann transport theory. The high quality, wide band gap, and reduced electrical resistance make ZnS a suitable candidate for the window layer in solar cells.

3.
Nanomaterials (Basel) ; 12(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35889606

RESUMO

The results of studies on the wettability properties and preparation of porous anodic alumina (PAA) membranes with a 3.3 ± 0.2 µm thickness and a variety of pore sizes are presented in this article. The wettability feature results, as well as the fabrication processing characteristics and morphology, are presented. The microstructure effect of these surfaces on wettability properties is analyzed in comparison to outer PAA surfaces. The interfacial contact angle was measured for amorphous PAA membranes as-fabricated and after a modification technique (pore widening), with pore sizes ranging from 20 to 130 nm. Different surface morphologies of such alumina can be obtained by adjusting synthesis conditions, which allows the surface properties to change from hydrophilic (contact angle is approximately 13°) to hydrophobic (contact angle is 100°). This research could propose a new method for designing functional surfaces with tunable wettability. The potential applications of ordinary alumina as multifunctional films are demonstrated.

4.
Radiat Prot Dosimetry ; 198(1-2): 86-99, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35098312

RESUMO

Present study was aimed to investigate trace elemental composition and possible elemental correlation with depth of some Pakistani wells. Exploratory oil wells of Toot oilfield from Potwar region of upper Indus basin were selected for this purpose. Samples of well cuttings and soil sections were collected with the assistance of Oil and Gas Development Company Limited. Elemental analyses were performed using instrumental neutron activation analysis. This study is the first of its kind to report detailed elemental profile of Toot oilfield, Attock, Punjab, Pakistan, via instrumental neutron activation analysis (INAA). Source formation of Toot oilfield is characterized by Jurassic Datta formation. Around 19-26 elements were identified by INAA. Major, minor and trace elemental concentrations varied with depths along the sampling lines. Data analysis was performed by the application of principal component analysis (PCA). PCA was useful in differentiating between surface and depth samples. Elemental volumes of different wells were established through bi-plots. In extension, naturally occurring radioactive materials and technologically enhanced naturally occurring radioactive materials were also determined for the wells of Toot oilfield. Annual dose rates and activity levels were calculated in oil well formations. Measurements of annual dose rates fall within safe limits, indicating anodyne atmosphere. Contamination indices, such as enrichment factor with respect to Al, geo accumulation index (Igeo), pollution index and integrated pollution index, were also determined. Cr and Zn were found to cross the safe limits, which may be due to the local industrial and anthropogenic activities.


Assuntos
Campos de Petróleo e Gás , Espectrometria gama , Monitoramento Ambiental/métodos , Análise de Ativação de Nêutrons , Paquistão , Solo/química
5.
Mater Sci Eng C Mater Biol Appl ; 129: 112384, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34579903

RESUMO

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has become a threat to global health because of limited treatments. MRSA infections are difficult to treat due to increasingly developing resistance in combination with protective biofilms of Staphylococcus aureus (S. aureus). Nanotechnology-based research revealed that effective MRSA treatments could be achieved through targeted nanoparticles (NPs) that withstand biological films and drug resistance. Thus, the principal aim towards improving MRSA treatment is to advance drug delivery tools, which successfully address the delivery-related problems. These potential delivery tools would also carry drugs to the desired sites of therapeutic action to overcome the adverse effects. This review focused on different types of nano-engineered carriers system for antimicrobial agents with improved therapeutic efficacy of entrapped drugs. The structural characteristics that play an essential role in the effectiveness of delivery systems have also been addressed with a description of recent scientific advances in antimicrobial treatment, emphasizing challenges in MRSA treatments. Consequently, existing gaps in the literature are highlighted, and reported contradictions are identified, allowing for the development of roadmaps for future research.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus
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