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1.
Langmuir ; 40(19): 10184-10194, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38699923

RESUMO

We report the controlled synthesis of iron oxide microcubes (IOMCs) through the self-assembly arrays of ferric oxide hydroxide nanorods (NRs). The formation of IOMCs involves a complex interplay of nucleation, self-assembly, and growth mechanisms influenced by time, thermal treatment, and surfactant dynamics. The self-assembly of vertically aligned NRs into IOMCs is controlled by dynamic magnetism properties and capping agents like cetyltrimethylammonium bromide (CTAB), whose concentration and temperature modulation dictate growth kinetics and structural uniformity. These controlled structural growths were obtained via a hydrothermal process at 120 °C at various intervals of 8, 16, 24, and 32 h in the presence of CTAB as the capping agent. In this hydrothermal method, the formation of vertically oriented NR arrays was observed without the presence of ligands, binders, harsh drying techniques, and solvent evaporation. The formation of the self-assembly of NRs to IOMCs is obtained with an increase in saturated magnetization to attain the most stable state. The synthesized IOMCs have a uniform size, quasi-shape, and excellent dispersion. Due to its excellent magnetic and catalytic properties, IOMCs were employed to remove the various emerging pollutants known as per- and polyfluorinated substances (PFAS). Various microscopic and spectroscopic techniques were employed for the characterization and interaction studies of IOMCs with various PFAS. The interaction between IOMCs and perfluoroalkyl substances (PFAS) was investigated, revealing strong adsorption tendencies facilitated by electrostatic interactions, as evidenced by UV-vis and FT-IR spectroscopic studies. Furthermore, the higher magnetic and positive surface charge of IOMCs is responsible for an effective remediation eliminating any secondary pollution with ease of recovery after the sorption interaction studies, thereby making it practically worthwhile.

2.
J Nanosci Nanotechnol ; 15(10): 7980-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26726451

RESUMO

Palmitoyl grafted modified cellulose were prepared by simple chemical grafting method and applied as nano adsorbent for removal of pyrene from aqueous solution. The chemical properties and morphology of prepared nano-adsorbent were characterized by FT-IR, XRD, SEM, EDX, TGA, and contact angle. Results showed that palmitoyl successfully grafted on the surface of cellulose and possess effective organic functional groups for the adsorption of pyrene from aqueous solution. The adsorption performance of modified cellulose was significantly improved toward pyrene in aqueous solution. It is worthy to note that 0.25 g of palmitoyl grafted cellulose (PMC) removed 92% pyrene compared to unmodified cellulose which adsorbed 36% pyrene from 1.65 ppm aqueous solution of pyrene in very short contact time at room temperature. Results showed that, presence of various organic functional groups from palmitoyl chains grafted on cellulose backbone affected to pyrene removal. After completion of adsorption phenomenon nano-adsorbent can be removed by simply filtration process and reused several times. The adsorption capacity was studied under different experimental conditions and their effects on adsorption such as temperature, pH, and contact time were also studied. The kinetics and isotherms of material were also determined.


Assuntos
Celulose/química , Nanopartículas/química , Ácido Palmítico/química , Pirenos/química , Purificação da Água/métodos , Adsorção
3.
J Nanosci Nanotechnol ; 15(10): 7988-96, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26726452

RESUMO

Electro-spun fabricated TiO2 nanofibers were prepared by simple electro-spinning method, in subsequent step silver (Ag) was deposited using precipitation method and obtained Ag-TiO2 composite nanofibers. The properties and morphology of these prepared composite nanofibers were characterized by XRD, SEM, EDX, and TGA. The prepared electro-spun composite nanofibers were applied as catalyst for the photodegradation of Congo-red under immited solar light in aqueous solution. Result reveals that, Ag loaded TiO2 composite nanofibers were effectively increased photodegradation of Congo red compared with pure TiO2 nanofibers in analogous condition. As a result, 92.0% decomposition of Congo red was obtained by using 5 wt% of Ag loaded TiO2 composite nanofibers at room temperature in short reaction time using 300 W of solar light. In addition, photodegradation of Congo red was also studied under different experimental conditions such as amount of Ag loaded in TiO2 nanofibers and contact time. Moreover, we also studied sintering effect on TiO2 nanofibers and their consequent effect on photodegradation reaction. After completion of reaction, the nanofibers can be easily separated by filtration process and reused several times without significant loss of activity. Overall study reveals that, Ag-TiO2 composite nanofibers were strongly enhanced the surface activity for the photo catalytic degradation of Congo red under ambient condition.


Assuntos
Vermelho Congo/química , Nanocompostos/química , Nanofibras/química , Prata/química , Titânio/química , Nanocompostos/ultraestrutura , Nanofibras/ultraestrutura , Processos Fotoquímicos
4.
ACS Omega ; 9(7): 7869-7880, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38405531

RESUMO

Laser-induced graphene (LIG) has received great interest as a potential candidate for electronic and sensing applications. In the present study, we report the enhanced performance of a manganese carbonate-decorated LIG (MnCO3/LIG) composite electrode material employed for electrochemical glucose detection. Initially, the porous LIG was fabricated by directly lasing poly(ether sulfone) membrane substrate. Then, the MnCO3/LIG composite was synthesized via a hydrothermal method. Later, MnCO3/LIG was immobilized onto a glassy carbon electrode surface and employed for glucose detection. The structure of the MnCO3/LIG composite was carefully characterized. The influence of the MnCO3/LIG composite on the performance of the electrode was investigated using cyclic voltammetry curves. The MnCO3/LIG composite exhibited an excellent sensitivity of 2731.2 µA mM-1 cm-2, and a limit of detection of 2.2 µM was obtained for the detection of glucose. Overall, the performance of the MnCO3/LIG composite was found to be superior to that of most of the MnCO3-based composites.

5.
ChemSusChem ; 17(7): e202301009, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38084066

RESUMO

Magnesium (Mg) has received very little exploration on its importance in the realm of battery-type energy storage technologies. They are abundantly present in seawater, and if successfully extracted and utilized in energy storage systems, it could lead to the long-term advancement of human civilization. Here, we fabricated an all-solid-state supercapacitor (ASSSC) using tellurium nanotubes decorated cobalt magnesium telluride microtubes (Te NTs@CoMgTe MTs) clad on nickel foam (NF). Owing to the unique mixed phase hierarchical structure, Te NTs@CoMgTe MTs showcases some advancement in energy storage performance. When tested in a three-electrode system, multiphasic hybrid of elemental Te and metal tellurides, Te NTs@CoMgTe MTs outperforms the monometallic telluride owing to the strong synergistic interaction effect triggered from conductive three components and delivers a long-life span performance up to 15,000 cycles. The fabricated Te NT@CoMgTe MT//AC solid-state device exhibits a maximum areal capacity of 59.2 µAh cm-2 (56.3 mAh g-1) at a current density of 6 mA cm-2 with a maximum energy density of 42.2 Wh kg-1 (46.5 µWh cm-2) at a power density of 6857.1 W kg-1 (7574.6 µW cm-2). The performance of the device is rigid even at different bending angles (0 to 180°) which validates the extensibility of the process for future applications.

6.
Front Reprod Health ; 5: 1115643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954895

RESUMO

Background: The tribal culture views health care practices differently from the mainstream. Infertile tribal women practice treatment-seeking behaviour that reflects the community's cultural access to and availability of treatment as well as customs to meet their health care needs. In the environment of rising awareness of infertility and numerous treatment options, this study aims to highlight the infertility treatment-seeking behaviour of tribal communities. Data and methods: The study employed a mix methods approach to collect data from 153 tribal couples suffering with infertility (interview schedule) and the community (in-depth interviews-14 and focus group discussions-12). The data was analyzed using Stata 13.0, and NVivo 10. Results of the quantitative data were triangulated with qualitative data for writing. Results: Many treatment options were available for infertility in the community. Generally, traditional healers (98.7%) were preferred over modern healthcare practitioners (35%). Community members usually guided infertile couples for choosing providers. Treatment practices were very different among primary infertile women than sub-fertile. Women frequently discontinued treatment and switched between providers because of unaffordability, poor connectivity, distance, travel time, time constraints, and non-supportive circumstances. The couples were advised to consume herbs, and eat or avoid certain food items, were given massage, burns on the abdomen (dagani), removed black blood (phasani) and other various rituals to appease spirits, get rid of ghosts while offering animal sacrifice, and conducting shidwa ritual. The mean expenditure on treatment was INR 18,374. If treatment did not yield any result, couple resorted to add another wife, divorce, accept childlessness and foster a child. Conclusion: Local authorities should strive to work towards the socio-economic development of the tribal communities and provide good healthcare services at their doorstep. The infertility problem needs to be understood in the context of poverty, tribal beliefs, and unequal access to healthcare resources.

7.
ACS Appl Mater Interfaces ; 15(18): 21994-22011, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37114882

RESUMO

The excess anthropogenic CO2 depletion via the catalytic approach to produce valuable chemicals is an industrially challenging, demanding, and encouraging strategy for CO2 fixation. Herein, we demonstrate a selective one-pot strategy for CO2 fixation into "oxazolidinone" by employing stable porous trimetallic oxide foam (PTOF) as a new catalyst. The PTOF catalyst was synthesized by a solution combustion method using transition metals Cu, Co, and Ni and systematically characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), N2 sorption, temperature-programmed desorption (TPD), and X-ray photoelectron spectroscopy (XPS) analysis. Due to the distinctive synthesis method and unique combination of metal oxides and their percentage, the PTOF catalyst displayed highly interconnected porous channels along with uniformly distributed active sites on its surface. Well ahead, the PTOF catalyst was screened for the fixation of CO2 into oxazolidinone. The screened and optimized reaction parameters revealed that the PTOF catalyst showed highly efficient and selective activity with 100% conversion of aniline along with 96% selectivity and yield toward the oxazolidinone product at mild and solvent-free reaction conditions. The superiority of the catalytic performance could be due to the presence of surface active sites and acid-base cooperative synergistic properties of the mixed metal oxides. A doubly synergistic plausible reaction mechanism was proposed for the oxazolidinone synthesis experimentally with the support of DFT calculations along with bond lengths, bond angles, and binding energies. In addition, stepwise intermediate formations with the free energy profile were also proposed. Also, the PTOF catalyst displayed good tolerance toward substituted aromatic amines and terminal epoxides for the fixation of CO2 into oxazolidinones. Very interestingly, the PTOF catalyst could be significantly reused for up to 15 consecutive cycles with stable activity and retention in physicochemical properties.

8.
RSC Adv ; 13(46): 32110-32125, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37920763

RESUMO

Benzimidazole derivatives are considered as important heterocyclic motifs that show a wide range of pharmaceutical applications. In view of their wide-ranging bioactivities, it is imperative to direct research on the sustainable catalytic synthesis of benzimidazole. Therefore, herein, we report a novel approach for the synthesis of benzimidazole and its derivatives with engineered MgO supported on dendritic fibrous nano silica (MgO@DFNS) as a sustainable heterogeneous catalyst. The catalyst MgO@DFNS was thoroughly characterized to understand its physio-chemical properties using XRD, FE-SEM, XPS, FT-IR, zeta potential, HR-TEM, TGA, TPR and TPD. The obtained results suggested that the catalyst MgO@DFNS prepared well and have the desired characteristics in it. After the successful characterisation of the prepared catalyst MgO@DFNS, it was applied in the synthesis of benzimidazole derivatives via condensation of o-phenylenediamine, and various aromatic and aliphatic aldehydes under ambient temperature. The catalyst produced a clean reaction profile with excellent yields in a shorter time under the umbrella of green chemistry. The effect of reaction parameters such as the effect of time, catalyst dosage, loading of MgO, effect of solvents and effect of different homo and heterogeneous catalyst were also tested. Furthermore, to understand the scope of the catalyst different substituted diamines and substituted aldehydes were reacted and obtained desired products in good to efficient yield. In addition, a recyclability study was also conducted and it was observed that the catalyst could be recycled for up to six cycles without noticeable changes in the morphology and activity. We believe that the present methodology gave several advantages such as an eco-friendly method, easy work-up, good selectivity, high yields and quick recovery of catalyst. MgO@DFNS is highly stable for several cycles without significant loss of its activity, which possibly demonstrates its applicability at the industrial scale.

9.
ACS Appl Mater Interfaces ; 15(43): 50134-50147, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37870918

RESUMO

This work showcases a novel strategy for the synthesis of shape-dependent alloy nanostructures with the incorporation of solid substrates, leading to remarkable enhancements in the electrocatalytic performance. Herein, an aqueous medium approach has been used to synthesize an octahedral PdXCuY alloy of different Pd:Cu ratios to better comprehend their electrocatalytic potential. With the aim to outperform high activity and efficient stability, zirconium oxide (ZrO2), graphene oxide nanosheets (GONs), and hexagonal boron nitride nanosheets (hBNNs) solid substrates are occupied to decorate the optimized Pd3Cu7 catalyst with a minimum 5 wt % metal loading. When compared to the counterparts and different ratios, the Pd3Cu7@hBNNs catalyst exhibited an optimal activity for hydrogen evolution reaction (HER). The lower overpotential and Tafel values observed are 64 and 51 mV/dec for Pd3Cu7@hBNNs followed by Pd3Cu7@ZrO2, which showed a 171 mV overpotential and a 98 mV/dec Tafel value, respectively. Meanwhile, the Pd3Cu7@GONs were found to have a 202 mV overpotential and a 110 mV/dec Tafel value. The density functional theory, which achieves a lower free energy (ΔGH*) value for Pd3Cu7@hBNNs than the other catalysts for HER, further supports its excellent performance in achieving the Volmer-Heyrovsky mechanism path. Moreover, the superior HER activity and sturdier resilience after 8 h of stability may be due to the synergy between the metal atoms, monodisperse decoration, and the coordination effect of the support material.

10.
Int J Biol Macromol ; 226: 690-705, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36513179

RESUMO

In this study, polyurethane (PU) and cellulose acetate (CA) electrospun fibers encapsulating rosemary essential oil (REO) and adsorbed silver (Ag) nanoparticles (NPs) were fabricated. The biologically inspired materials were analyzed for physicochemical characteristics using scanning electron microscopy, X-ray diffractometer, Fourier transform infrared, thermal gravimetric analysis, X-ray photoelectron spectroscopy, water contact angle, and water uptake studies. Results confirmed the presence of CA and Ag NPs on the PU micro-nanofibers increased the hydrophilicity from 107.1 ± 0.36o to 26.35 ± 1.06o. The water absorption potential increased from 0.07 ± 0.04 for pristine PU fibers to 12.43 ± 0.49 % for fibers with 7 wt% of CA, REO, and Ag NPs. The diffractometer confirmed the 2θ of 38.01°, 44.13o, and 64.33o, corresponding to the diffraction planes of Ag on the fibers. The X-ray photoelectron spectroscopy confirmed microfibers interfacial chemical interaction and surface changes due to CA, REO, and Ag presence. The inhibition tests on Staphylococcus aureus and Escherichia coli indicated that composites are antibacterial in activity. Moreover, synergistic interactions of REO and Ag NPs resulted in superior antibacterial activity. The cell viability and attachment assay showed improved hydrophilicity of the fibers, which resulted in better attachment of cells to the micro-nanofibers, similar to the natural extracellular matrix in the human body.


Assuntos
Nanopartículas Metálicas , Nanofibras , Óleos Voláteis , Rosmarinus , Humanos , Poliuretanos , Prata/química , Nanopartículas Metálicas/química , Nanofibras/química , Antibacterianos/farmacologia , Antibacterianos/química , Óleos Voláteis/farmacologia , Cicatrização
11.
RSC Adv ; 12(23): 14740-14756, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35702231

RESUMO

1,5-Benzodiazepine is considered as one of the central moieties in the core unit of most drug molecules. Construction of such moieties with a new C-N bond under solvent-free and mild reaction conditions is challenging. Herein, we present a benign protocol for one pot synthesis of 1,5-benzodiazepine derivatives by using ferrocene (FC) supported activated carbon (AC) as a heterogeneous catalyst. The catalyst FC/AC was characterized by several analytical and spectroscopic techniques to reveal its physicochemical properties and for structural confirmation. The synthesized catalyst FC/AC was explored for its catalytic activity in the synthesis of 1,5-benzodiazepines through condensation of o-phenylenediamine (OPDA) and ketones (aromatic and aliphatic) under solvent-free conditions. The robust 10 wt% FC/AC catalyst demonstrated appreciable activity with 99% conversion of diamines and 91% selectivity towards the synthesis of the desired benzodiazepine derivatives under solvent-free conditions at 90 °C in 8 h. Additionally, several reaction parameters such as catalyst loading, reaction temperature, effect of reaction time and effect of different solvents on selectivity were also studied and discussed in-depth. To understand the scope of the reaction, several symmetrical and unsymmetrical ketones along with different substituted diamines were tested with the synthesized catalyst. All prepared reaction products were obtained in good to efficient yields and were isolated and identified as 1,5-benzodiazepines and no side products were observed. The obtained catalyst characterization data and the activity studies suggested that, the synergetic effect occurred due to the uniform dispersion of ferrocene over the AC surface with numerous acidic sites which triggered the reaction of diamine and ketone to form the corresponding benzodiazepine derivative and the same was illustrated in the plausible mechanism. Furthermore, the synthesized catalyst was tested for leaching and recyclability, and the results confirmed that catalyst can be used for up to six consecutive cycles without much loss in the catalytic activity and its morphology which makes the process sustainable and economical for scale-up production. The present method offered several advantages such as an ecofriendly method, excellent yields, sustainable catalytic transformation, easy work-up and isolation of products, and quick recovery of catalyst.

12.
ACS Omega ; 7(4): 3324-3340, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128243

RESUMO

Solvent-based recycling of plastic can offer the main improvement when it is employed for pyrolysis-catalytic steam reforming. In this research, plastic waste dissolved in phenol was used as a feed for catalytic cracking and steam reforming reactions for valuable liquid fuels and hydrogen production, which is gaining the attention of researchers globally. Microplastic wastes (MPWs) are tiny plastic particles that arise due to product creation and breakdown of larger plastics. They can be found mainly in several habitats, including seas and freshwater ecosystems. MPWs harm aquatic species, turtles, and birds and were chosen to recover in this study that can be reacted on the catalyst surface. Biphasic anatase-rutile TiO2 with spherical-shaped support for Ni and Pd metals with nanosized particles was synthesized via the hydrothermal treatment method, and its chemical and physical properties were characterized accordingly. According to temperature-programmed desorption of carbon dioxide (CO2-TPD) and temperature-programmed reduction of hydrogen (H2-TPR) results, the incorporation of Pd into Ni/TNPs enhanced the basicity of the support surface and the redox properties of catalysts, which were strongly linked to the improved hydrogen yield (71%) and phenol conversion (79%) at 600 °C. The Ni-Pd/TNPs nanocatalyst, with remarkable stability for 72 h of time on stream, is a promising catalyst for the MPW-phenol cracking and steam reforming reactions toward H2 production for clean energy generation and other environmental applications. Besides, this study has also highlighted the opportunities of overcoming the risk of microplastic waste and converting it into valuable fuels such as decamethyltetrasiloxane, phenanthrene, methyl palmitate, benzenepropanoic acid, benzoic acid, azulene, xanthene, anisole, biphenyl, phthalic acid, diisooctyl phthalate, etc.

13.
RSC Adv ; 12(3): 1604-1627, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35425206

RESUMO

Sustainable renewable energy production is being intensely disputed worldwide because fossil fuel resources are declining gradually. One solution is biodiesel production via the transesterification process, which is environmentally feasible due to its low-emission diesel substitute. Significant issues arising with biodiesel production are the cost of the processes, which has stuck its sustainability and the applicability of different resources. In this article, the common biodiesel feedstock such as edible and non-edible vegetable oils, waste oil and animal fats and their advantages and disadvantages were reviewed according to the Web of Science (WOS) database over the timeframe of 1970-2020. The biodiesel feedstock has water or free fatty acid, but it will produce soap by reacting free fatty acids with an alkali catalyst when they present in high portion. This reaction is unfavourable and decreases the biodiesel product yield. This issue can be solved by designing multiple transesterification stages or by employing acidic catalysts to prevent saponification. The second solution is cheaper than the first one and even more applicable because of the abundant source of catalytic materials from a waste product such as rice husk ash, chicken eggshells, fly ash, red mud, steel slag, and coconut shell and lime mud. The overview of the advantages and disadvantages of different homogeneous and heterogeneous catalysts is summarized, and the catalyst promoters and prospects of biodiesel production are also suggested. This research provides beneficial ideas for catalyst synthesis from waste for the transesterification process economically, environmentally and industrially.

14.
Chemosphere ; 290: 133296, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34914962

RESUMO

The fatty acid methyl ester (FAME) production from dairy effluent scum as a sustainable energy source using CaO obtained from organic ash over titanium dioxide nanoparticles (TNPs) as the transesterification nano-catalyst has been studied. The physical and chemical properties of the synthesized catalysts were characterized, and the effect of different experimental factors on the biodiesel yield was studied. It was revealed that the CaO-TiO2 nano-catalyst displayed bifunctional properties, has both basic and acid phases, and leads to various effects on the catalyst activity in the transesterification process. These bifunctional properties are critical for achieving simultaneous transesterification of dairy scum oil feedstock. According to the reaction results, the catalyst without and with a low ratio of TNPs showed a low catalytic activity. In contrast, the 3Ca-3Ti nano-catalyst had the highest catalytic activity and a strong potential for reusability, producing a maximum biodiesel yield of 97.2% for a 3 wt% catalyst, 1:20 oil to methanol molar ratio for the dairy scum, and a reaction temperature of 70 °C for a period of 120 min under a 300 kPa pressure. The physical properties of the produced biodiesel are within the EN14214 standards.


Assuntos
Biocombustíveis , Titânio , Compostos de Cálcio , Catálise , Esterificação , Óxidos , Óleos de Plantas
15.
Mater Sci Eng C Mater Biol Appl ; 118: 111547, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255098

RESUMO

Cellulose nanofibers, which are troublesome to spin into fibers, can be easily fabricated by post-regeneration of its acetate-derived threads. Cellulose is a natural polymer; it enjoys better biocompatibility, cellular mimicking, and hydrophilic properties than its proportionate analog. Herein, we regenerated acetate-free nanofibers by alkaline de-acetylation of as-spun nanofibers. The resultant cellulose nanofibers previously loaded with hydroxyapatite (HAp) were immobilized using silver (Ag) nanoparticles (NPs) by reduction of adsorbed Ag ions on using sodium borohydride. These amalgamated nanofibers were characterized for SEM, EDX, TEM, FTIR, and hydrophilicity tests revealing the existence of both HAp and Ag NPs in/on the nanofiber scaffolds. The de-acetylation of composite nanofibers resulted in spontaneous hydrophilicity. These nanofibers were cytocompatible, as resolved by MTT assay conducted on chicken embryo fibroblasts. The SEM of the samples after cell culture revealed that these composites allowed a proliferation of the fibroblasts over and within the nanofiber network, and increased concentration of HAp levitated the excessive of apatite formation as well as increased cell growth. The antimicrobial activity of these nanofibers was assessed on E. coli (BL21) and S. aureus, suggesting the potential of de-acetylated nanofibers to restrain bacterial growth. The degradation study for 10, 30, and 60 days indicated degradation of the fibers much is faster in enzymes as compared to degradation in PBS. The results certify that these nanofibers possess enormous potential for soft and hard tissue engineering besides their antimicrobial properties.


Assuntos
Nanofibras , Nanopartículas , Animais , Celulose/análogos & derivados , Embrião de Galinha , Durapatita , Escherichia coli , Prata/farmacologia , Staphylococcus aureus , Engenharia Tecidual
16.
Chemosphere ; 281: 130988, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289632

RESUMO

Catalytic hydrolysis of sodium borohydride can potentially be considered as a convenient and safe method to generate hydrogen, an environmentally clean and sustainable fuel for the future. The present effort establishes the development of FeCuCo tri-metallic oxide catalyst by a simple, single-step solution combustion synthesis (SCS) method for hydrogen generation from NaBH4 hydrolysis. Amongst series of FeCuCo tri-metallic oxide catalyst synthesized, FeCuCo with 50:37.5:12.5 wt% respective precursor loading displayed remarkable activity by generating hydrogen at the rate of 1380 mL min-1 g-1 (1242 mL in 18 min) with turnover frequency (TOF) of 62.02 mol g-1 min-1. The catalyst was characterized by using various techniques to understand their physiochemical and morphological properties. The results revealed that the catalyst synthesized by combustion method led to the formation of FeCuCo with appreciable surface area, porous foam-like morphology and high surface acidity. Major factors affecting the hydrolysis of NaBH4 such as catalyst loading, NaOH concentration and temperature variation were studied in detail. Additionally, the FeCuCo catalyst also displayed substantial recyclability performance up to eight cycles without considerable loss in its catalytic activity. Therefore, FeCuCo oxide can be demonstrated as one of the most efficient, cost effective tri-metallic catalyst so far for application in the hydrogen generation.


Assuntos
Hidrogênio , Óxidos , Catálise , Hidrólise
17.
Sci Rep ; 6: 31120, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27506839

RESUMO

Ternary spinel CuCo2O4 nanostructure clenches great potential as high-performance electrode material for next-generation energy storage systems because of its higher electrical conductivity and electrochemical activity. Carbon free and binder free 3D flower-like CuCo2O4 structure are grown on nickel foam (NF) via a facile hydrothermal synthesis method followed by annealing. The obtained CuCo2O4/NF is directly used as electrode for lithium ion batteries (LIBs) and supercapacitors (SCs) application. The electrochemical study of 3D flower-like CuCo2O4 as an electrode for LIB and SC shows highly mesoporous unique architecture plays important role in achieving high capacity/capacitance with superior cycle life. The high surface area and mesoporous nature not only offer sufficient reaction sites, but also can accelerate the liquid electrolyte to penetrate electrode and the ions to reach the reacting sites. In outcome, it exhibits highest capacity of 1160 mA h g(-1) after 200 cycles when used as an anode for LIB and specific capacitance of 1002 F g(-1) after 3000 cycles. The superior electrochemical of synthesized material is attributed to direct contact of electrode active material with good intrinsic electrical conductivity to the underneath conductive NF substrate builds up an express path for fast ion and electron transfer.

18.
J Nanosci Nanotechnol ; 15(10): 8243-50, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26726496

RESUMO

Aluminum trichloride (AlCl3) impregnated molybdenum oxide heterogeneous nano-catalyst was prepared by using simple impregnation method. The prepared heterogeneous catalyst was characterized by powder X-ray diffraction, FT-IR spectroscopy, solid-state NMR spectroscopy, SEM imaging, and EDX mapping. The catalytic activity of this protocol was evaluated as heterogeneous catalyst for the Friedel-Crafts acylation reaction at room temperature. The impregnated MoO4(AlCl2)2 catalyst showed tremendous catalytic activity in Friedel-Crafts acylation reaction under solvent-free and mild reaction condition. As a result, 84.0% yield of acyl product with 100% consumption of reactants in 18 h reaction time at room temperature was achieved. The effects of different solvents system with MoO4(AlCl2)2 catalyst in acylation reaction was also investigated. By using optimized reaction condition various acylated derivatives were prepared. In addition, the catalyst was separated by simple filtration process after the reaction and reused several times. Therefore, heterogeneous MoO4(AlCl2)2 catalyst was found environmentally benign catalyst, very convenient, high yielding, and clean method for the Friedel-Crafts acylation reaction under solvent-free and ambient reaction condition.

19.
Artigo | IMSEAR | ID: sea-202725

RESUMO

Introduction: Saroglitazar is known to safely and effectivelyimprove dyslipidemia by reducing triglyceride (TG), lowdensity lipoprotein (LDL) cholesterol, very low-densitylipoprotein (VLDL) cholesterol, non-high-density lipoprotein(non-HDL) cholesterol and increasing high densitylipoprotein (HDL) cholesterol. In addition, saroglitazar canimprove glycemic indices in diabetic patients by reducingfasting plasma glucose (FPG) and glycosylated haemoglobin(HbA1c). Aim of the study was to evaluate the hospital basedclinic-pathological profile, diagnosis, treatment and followup of Indian patients with Non-alcoholic fatty liver diseaseand to evaluate the safety and efficacy of Saroglitazar 4 mg inpatients with Non-alcoholic fatty liver disease /Non-alcoholicSteatohepatitis in real life setting.Material and methods: This was an ongoing observationalstudy with the sample size of 52 patients having Nonalcoholic fatty liver disease and dyslipidaemia with or withoutType 2 Diabetes Mellitus and treatment follow up for a periodof 1 year in the Department Of Gastroenterology. The datawas collected from eligible patients who have been prescribedSaroglitazar 4 mg once daily in routine clinical practice.Primary endpoints were to see liver stiffness. Secondaryendpoints were to measure serum alanine aminotransferase,aspartate aminotransferase level and Serum triglycerideslevel.Results: There was a significant decrease in Serum alanineaminotransferase (p <0.001), aspartate aminotransferase (pvalue < 0.001), triglycerides (p value <0.001) and triglycerides(p value 0.01), levels after the treatment as compared to thebaseline.Conclusion: Saroglitazar treatment is effective and there isa significant difference in Serum alanine aminotransferaseand aspartate aminotransferase, triglycerides and LiverStiffness Measurement levels after treatment. The drug can besuccessfully administered for the treatment of Non-alcoholicfatty liver disease.

20.
Bioresour Technol ; 132: 342-50, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23435221

RESUMO

Acidity modified silver exchanged silicotungstic acid (AgSTA) catalyst was prepared and characterized by X-ray diffraction, FT-IR spectroscopy, Raman spectroscopy, FT-IR pyridine adsorption, SEM imaging, EDX mapping, and antimicrobial activity was also tested. The catalytic activity was evaluated for the dehydration of fructose and sucrose in superheated water. As a result, 98% conversion of fructose with 85.7% HMF yield and 87.4% HMF selectivity in 120 min reaction time at 120 °C reaction temperature using 10 wt.% of AgSTA catalyst was achieved. While, 92% sucrose conversion with 62.5% of HMF yield was obtained from sucrose at uniform condition in 160 min. The effect of reaction parameters, such as reaction temperature, time, catalyst dosage, and effect acidity on HMF yield was also investigated. The AgSTA catalyst was separated from the reaction mixture by filtration process at end of the reaction and reused eight times without loss of catalytic activity.


Assuntos
Biocombustíveis , Frutose/química , Furaldeído/análogos & derivados , Temperatura Alta , Silicatos/química , Sacarose/química , Compostos de Tungstênio/química , Catálise , Furaldeído/síntese química , Microscopia Eletrônica de Varredura , Estrutura Molecular , Prata , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Água , Difração de Raios X
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