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1.
Int J Biol Macromol ; 253(Pt 3): 126885, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37709213

RESUMO

In this research paper, a novel process was developed for reactive printing of cotton fabric, with the objective of producing a high-quality printed fabric that is sustainable, eco-friendly, and low-cost which will ultimately reduce the impact of climate change. The study incorporated substituted tamarind polysaccharide (STP) obtained from agricultural waste, trichloro-ethanoic acid (TCEA), and polyethylene glycol (PEG-400) in the reactive printing paste. Tamarind starch was extracted from the seeds having 72 % yield, and substitution was performed to use it as a thickener in the printing paste. The conventional printing system was formulated with sodium alginate, urea, and sodium bicarbonate at dose levels of 2 %, 15 %, and 2.5 %, respectively, while the modified recipe was formulated with STP and TCEA at 5 % and 3 % dose levels, respectively along with varying doses of PEG-400 (0 %, 1 %, and 2 %) in novel prints. Various factors such as shade comparison, penetration, staining on the white ground, washing, rubbing, light and perspiration fastness, sharpness of edges, and fabric hardness were evaluated for all the recipes. The study demonstrated that the optimal outcomes were obtained with a 2 % PEG-400 dose level. This study represents a significant contribution to sustainable textile production, as tamarind agriculture waste was used as a raw material, which is an environmentally friendly alternative of sodium alginate that reduces the wastewater load. Additionally, PEG-400 was utilized as a nitrogen-free solubilizing moisture management substitution of urea for printing, while TCEA dissociated at high temperature to make alkaline pH during curing of the printed fabric to replace sodium bicarbonate. This research is a novel contribution to the printing industry, as these three constituents have not been previously used together other than this research group, in the history of reactive printing.


Assuntos
Mudança Climática , Bicarbonato de Sódio , Alginatos , Agricultura , Ureia
2.
ACS Omega ; 8(23): 21032-21041, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37323397

RESUMO

In this work, we report the engineering of sub-30 nm nanocomposites of CuO/ZnO/NiO by using Dodonaea viscosa leaf extract. Zinc sulfate, nickel chloride, and copper sulfate were used as salt precursors, and isopropyl alcohol and water were used as solvents. The growth of nanocomposites was investigated by varying the concentrations of precursors and surfactants at pH 12. The as-prepared composites were characterized by XRD analysis and found to have CuO (monoclinic), ZnO (hexagonal primitive), and NiO (cubic) phases with an average size of 29 nm. FTIR analysis was performed to investigate the mode of fundamental bonding vibrations of the as-prepared nanocomposites. The vibrations of the prepared CuO/ZnO/NiO nanocomposite were detected at 760 and 628 cm-1, respectively. The optical bandgap energy of the CuO/NiO/ZnO nanocomposite was 3.08 eV. Ultraviolet-visible spectroscopy was performed to calculate the band gap by the Tauc approach. Antimicrobial and antioxidant activities of the synthesized CuO/NiO/ZnO nanocomposite were investigated. It was found that the antimicrobial activity of the synthesized nanocomposite increases with an increase in the concentration. The antioxidant activity of the synthesized nanocomposite was examined by using both ABTS and DPPH assays. The obtained results show an IC50 value of 0.110 for the synthesized nanocomposite compared to DPPH and ABTS (0.512), which is smaller than that of ascorbic acid (IC50 = 1.047). Such a low IC50 value ensures that the antioxidant potential of the nanocomposite is higher than that of ascorbic acid, which in turn shows their excellent antioxidant activity against both DPPH and ABTS.

3.
Adv Sci (Weinh) ; 10(7): e2203889, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36683257

RESUMO

In the past few decades, 2D layer materials have gradually become a central focus in materials science owing to their uniquely layered structural qualities and good optoelectronic properties. However, in the development of 2D materials, several disadvantages, such as limited types of materials and the inability to synthesize large-scale materials, severely confine their application. Therefore, further exploration of new materials and preparation methods is necessary to meet technological developmental needs. Organic molecular materials have the advantage of being customizable. Therefore, if organic molecular and 2D materials are combined, the resulting 2D organic materials would have excellent optical and electrical properties. In addition, through this combination, the free design and large-scale synthesis of 2D materials can be realized in principle. Furthermore, 2D organic materials exhibit excellent properties and unique functionalities along with great potential for developing sensors, biomedicine, and electronics. In this review, 2D organic materials are divided into five categories. The preparation methods and material properties of each class of materials are also described in detail. Notably, to comprehensively understand each material's advantages, the latest research applications for each material are presented in detail and summarized. Finally, the future development and application prospects of 2D organic materials are briefly discussed.

4.
J Mol Graph Model ; 118: 108335, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36183685

RESUMO

In the paper, the wettability of different phases of TiO2 thin films (anatase, brookite, and rutile) have been studied using molecular-dynamics simulation. The principle of micro-wetting is discussed. The simulation results show that the contact angle decreases upon increasing the interaction energy between the water and the titanium dioxide interface during the wetting process. The values of contact angles from large to small are: rutile, brookite and anatase. The calculated equilibrium contact angles are 73.9°, 59.2°, and 43.7°, respectively. The reason is that the structural connection and the arrangement of the surface microtopography directly affect the movement of water droplets on the surface of the material, thus affecting the wettability. In addition, the amount of the interaction energy and the radial distribution function between these three interfaces and the droplets are calculated, and the density change of the droplet is analyzed further which indicate the difference in wetting between the three crystal structures. At the same time, by simulating and comparing the wettability of the trench surface and the original surface of anatase, it is inferred that the rough interface increases the contact angle with the droplet and reduces the wettability.

5.
Materials (Basel) ; 15(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35955354

RESUMO

Two-dimensional (2D) tri-TMDCs carrier dynamics provide a platform for studying excitons through Ultrafast Pump-Probe Transient Absorption Spectroscopy. Here we studied the ZrTe3 nanosheets (NTs) exciton dynamics by transient absorption (TA) spectrometer. We observed different carrier dynamics in the ZrTe3 NTs sample at different pump powers and with many wavelengths in the transient absorption spectrometer. The shorter life decay constant is associated with electron-phonon relaxation. Similarly, the longer-life decay constant represents the long live process that is associated with charge separation. The interactions between carrier-phonons at nanoscale materials can be changed by phonons quantum confinements. The hot carrier lifetime determined the strength of carrier phonon interactions. The value of fast decay in the conduction band is due to carrier relaxation or the carrier gets trapped due to surface states or localized defects. The value of slow decay is due to the recombination of surface state and localized defects processes. The lifetime declines for long wavelengths as size decreases. Whereas, during short wavelength-independent decay, carrier characteristics have been observed. TA spectroscopy is employed to investigate insight information of the carrier's dynamical processes such as carrier lifetime, cooling dynamics, carrier diffusion, and carrier excitations. The absorption enhanced along excitons density with the increase of pump power, which caused a greater number of carriers in the excited state than in the ground state. The TA signals consist of trap carriers and (electron-hole) constituents, which can be increased by TA changes that rely on photoexcitation and carrier properties.

6.
Food Chem ; 366: 130591, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34293548

RESUMO

For the shelf life extension of fruits, we envisioned a novel antimicrobial approach that is based on the production of a thin layer of hydrogen peroxide at the surface of food by utilizing the bioactivity of glucose oxidase (GOx). The enzyme, purified from Aspergillus Niger, was immobilized on zinc oxide nanoparticles and then suspended in a buffer to prepare a spraying solution of GOx/ZnONPs. Post-immobilization analyses indicated that immobilized enzyme showed higher activity as compared to the free enzyme. The GOx/ZnONPs spray was applied for postharvest treatment of peach. The control and treatment groups were stored at ambient conditions for fifteen days and standard quality parameters were analyzed. In contrast to the control group, the GOx/ZnONPs spray treatment was remarkably effective in maintaining the physiological appearance of fruits even more than 12 days and showed a significant reduction in the decrease of weight, firmness, TSS, and DPPH free radical scavenging activity of fruits. Thus GOx/ZnONPs is an excellent platform to extend the postharvest shelf life of peach.


Assuntos
Nanopartículas , Prunus persica , Óxido de Zinco , Enzimas Imobilizadas , Frutas , Glucose Oxidase
7.
Materials (Basel) ; 16(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36614468

RESUMO

The synthesis of nanoparticles (NPs) using the green route is environmentally harmonious and cost-effective compared to conventional chemical and physical methods. In this study, the green synthesis of silver NPs was carried out using an extract of Debregeasia salicifolia. The synthesized Ag NPs were characterized by means of different techniques i.e., UV-Vis spectroscopy, FTIR spectroscopy, SEM, and XRD. The XRD pattern exhibited distinctive Bragg's peaks at (200), (111), (311), and (220). The XRD analysis confirmed the face-centered cubic geometry of the synthesized NPs and revealed that the nature of these NPs is crystalline. The synthesized NPs were verified for their antibacterial activities against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria. It showed that antibacterial activity of synthesized silver (NPs) was increased with increasing concentrations of both calcined and non-calcined NPs. The antioxidant activities of Ag NPs were also determined against ABTS at different concentrations for both calcined and non-calcined Ag NPs. Non-calcined Ag NPs have greater antioxidant activity than calcined Ag NPs. This report has a significant medicinal application, and it might open up new horizons in this field.

8.
Carbohydr Polym ; 237: 116111, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32241453

RESUMO

The novel N-p-carboxy benzyl chitosan (CBC)/ poly (vinyl alcohol) (PVA) based mixed matrix membranes (MMMs) filled with surface-modified zeolite have been prepared using the dissolution casting technique. The applicability of prepared MMMs for direct methanol fuel cell (DMFC) was investigated in terms of water uptake, methanol permeation, and proton conductivity by changing filler content (10-50 wt. %). The zeolite was modified by silane coupling agent, 3-mercaptopropyltrimethoxysilane (MPTMS). The resultant modified zeolite (MZ) was incorporated into CBC/PVA blend to obtain mixed matrix PEMs. The functional group, structural properties, morphological and topographical investigation of MMMs were examined using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Scanning electron microscopy (SEM) respectively. The prepared MMMs exhibited a remarkable decrease in methanol permeability of 2.3 × 10-7  cm2/s with C-CPMZ50. The maximum value of proton conductivity of 0.0527 Scm-1, was shown by C-CMPZ10. The prepared PEMs also displayed good stability during long term operating time.

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