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1.
Sci Rep ; 14(1): 15694, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977838

RESUMO

This study investigates the use of carbonized Himalayan Chir Pine Biomass, known as Chir Pine Activated Carbon (CPAC), as an eco-friendly and cost-effective adsorbent for efficient industrial dye removal, with a focus on environmental sustainability. By applying different additive treatments, four adsorbents (C1, C2, C3, and C4) were formulated. CPAC was synthesized through pyrolysis and characterized using various analytical techniques including FE-SEM, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The adsorption capacity of CPAC was evaluated using Malachite Green (MG) dye as a model contaminant. FE-SEM images revealed high porosity (~ 10 µm) and a high surface area (119.886 m2/g) as confirmed by BET testing. CPAC effectively removed MG dye within 30 min at a solution pH of 7. Langmuir and Freundlich isotherm models indicated both monolayer and multilayer adsorption, while kinetic models suggested chemisorption. The regeneration efficiency was assessed using 0.1 N HCl over five consecutive cycles, with C4 demonstrating a high regeneration tendency of 85% and only a 9% reduction in adsorption ability after the fifth cycle. The developed CPAC shows excellent potential for use in the textile, paper, and leather industries for industrial dye adsorption, contributing to the protection of aquatic ecosystems. Additionally, CPAC can be utilized in other water and air purification applications.

2.
Int J Biol Macromol ; 274(Pt 2): 133512, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944080

RESUMO

Nanocellulose@chitosan (nc@ch) composite beads were prepared via coagulation technique for the elimination of malachite green dye from aqueous solution. As malachite green dye is highly used in textile industries for dyeing purpose which after usage shows fatal effects to the ecosystems and human beings also. In this study the formulated nanocellulose@chitosan composite beads were characterized by Particle size analysis (PSA), Field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis were done to evaluate nanoparticles size distribution, morphological behaviour, functional group entities and degree of crystallinity of prepared beads. The nanocomposite beads adsorption performance was investigated for malachite green (MG) dye and BET analysis were also recorded to know about porous behaviour of the nanocomposite beads. Maximum removal of malachite green (MG) dye was found to be 72.0 mg/g for 100 ppm initial dye concentration. For accurate observations linear and non-linear modelling was done to know about the best-fitted adsorption model during the removal mechanism of dye molecules, on evaluating it has been observed that Langmuir isotherm and Freundlich isotherm show best-fitted observation in the case of linear and non-linear isotherm respectively (R2 = 0.96 & R2 = 0.957). In the case of kinetic linear models, the data was well fitted with pseudo-second-order showing chemosorption mechanism (R2 = 0.999), and in the case of non-linear kinetic model pseudo first order showed good fit showing physisorption mechanism during adsorption (R2 = 0.999). The thermodynamic study showed positive values for ΔH° and ΔS° throughout the adsorption process respectively, implying an endothermic behaviour. In view of cost effectiveness, desorption or regeneration study was done and it was showed that after the 5th cycle, the removal tendency had decreased from 48 to 38 % for 20-100 ppm dye solution accordingly. Thus, nanocomposite beads prepared by the coagulation method seem to be a suitable candidate for dye removal from synthetic wastewater and may have potential to be used in small scale textile industries for real wastewater treatment.

3.
Int J Biol Macromol ; 254(Pt 3): 127465, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866583

RESUMO

Rapid growth in industrialization sectors, the wastewater treatment plants become exhausted and potentially not able to give desirable discharge standards. Many industries discharge the untreated effluent into the water bodies which affects the aquatic diversity and human health. The effective disposal of industrial effluents thus has been an imperative requirement. For decades nanocellulose based materials gained immense attraction towards application in wastewater remediation and emerged out as a new biobased nanomaterial. It is light weighted, cost effective, mechanically strong and easily available. Large surface area, versatile surface functionality, biodegradability, high aspect ratio etc., make them suitable candidate in this field. Majorly cellulose based nanomaterials are used in the form of cellulose nanocrystals (CNCs), cellulose nanofibers (CNFs), or bacterial nanocellulose (BNC). This review specifically describes about a variety of extraction methods to produced nanocellulose and also discusses the modification of nanocellulose by adding functionalities in its surface chemistry. We majorly focus on the utilization of nanocellulose based materials in water remediation for the removal of different contaminants such as dyes, heavy metals, oil, microbial colony etc. This review mainly emphasizes in ray of hope towards nanocellulose materials to achieve more advancement in the water remediation fields.


Assuntos
Nanofibras , Nanopartículas , Nanoestruturas , Humanos , Água , Nanoestruturas/química , Nanopartículas/química , Nanofibras/química , Celulose/química
4.
Aquat Toxicol ; 260: 106555, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37196506

RESUMO

The proficiency of microalgae to resist heavy metals has potential to be beneficial in resolving various environmental challenges. Global situations such as the need for cost-effective and ecological ways of remediation of contaminated water and for the development of bioenergy sources could employ microalgae. In a medium with the presence of heavy metals, microalgae utilize different mechanisms to uptake the metal and further detoxify it. Biosorption and the next process of bioaccumulation are two such major steps and they also include the assistance of different transporters at different stages of heavy metal tolerance. This capability has also proved to be efficient in eradicating many heavy metals like Chromium, Copper, Lead, Arsenic, Mercury, Nickel and Cadmium from the environment they are present in. This indicates the possibility of the application of microalgae as a biological way of remediating contaminated water. Heavy metal resistance quality also allows various microalgal species to contribute in the generation of biofuels like biodiesel and biohydrogen. Many research works have also explored the capacity of microalgae in nanotechnology for the formation of nanoparticles due to its relevant characteristics. Various studies have also revealed that biochar deduced from microalgae or a combination of biochar and microalgae can have wide applications specially in deprivation of heavy metals from an environment. This review focuses on the strategies adopted by microalgae, various transporters involved in the process of tolerating heavy metals and the applications where microalgae can participate owing to its ability to resist metals.


Assuntos
Metais Pesados , Microalgas , Poluentes Químicos da Água , Biodegradação Ambiental , Poluentes Químicos da Água/toxicidade , Metais Pesados/toxicidade , Metais Pesados/análise , Água
5.
Cureus ; 15(2): e34586, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36883084

RESUMO

Background Hypsarrhythmia is a classical multifocal electroencephalographic finding in patients of infantile spasm and related epileptic syndromes of early childhood including West syndrome and Otahara syndrome. It usually presents in early infancy and persists up to the age of two years, after which it usually resolves. The persistence of hypsarrhythmia beyond the age of two years has rarely been reported in the literature. The present study is an attempt to investigate and compare the origin and activation pattern of epileptic activity between the subjects aged 3-10 years with and without hypsarrythmia. Material and methods Forty-one patients in the age group of 3-10 years with features suggestive of seizure have been studied for quantitative electroencephalographic characteristics after dividing into hypsarrythmic and normal seizure patterns. Result The power spectral density (PSD) of 15 patients with hypsarrhythmia showed a significantly predominant delta frequency in quantitative electrography (qEEG) in comparison to the seizure subjects with normal electroencephalography (EEG) patterns. The amplitude progression analysis of both groups showed that the origin of focus of the hypsarrhythmic pattern is from the occipital region while no such pattern has been noticed in the control group. Discussion and conclusion Hypsarrythmia is known to show multifocal origin. Predominant occipital origin in older age group subjects distinguishes the condition from classical hypsarrythmia of early childhood. The occipital origin may be indicative of persistent immaturity of the thalamocortical synaptic pathway.

6.
Opt Quantum Electron ; 54(11): 762, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189113

RESUMO

The analytical modeling for linear and non-linear impairments (LNI) for single mode fiber (SMF) and simulative analysis of extended power budget class-1 i.e. E1-class of next generation passive optic network-2 (NG-PON2) is presented in the paper. The proposed power-budget class time and wavelength division multiplexing (TWDM) based NG-PON2 network configuration is delivering symmetric 2.5 point-to-multi point (PtM) representing time and TWDM XGS-PON along with 10 Gbps point-to-point (PtP) wavelength division multiplexing (WDM) symmetric and coexistent channels (Ch) in worst-case scenario. Channel modelling of LNI is carried out under the incremental and aggregate strain of estimated chromatic dispersion CD, self-phase modulation (SPM), cross-phase modulation (XPM) of single mode fiber (SMF) channel deployed in optical distributing network (ODN) between 20 and 50 km link lengths. Downlink (D/L) and uplink (U/L) ODN is optimized to PTODN = 7.1 dBm and 4.09 dBm, respectively and corresponding channel imparities including Kerr parameter Î³, corresponding SPM, XPM, CD, four-wave mixing (FWM) analysis and corresponding component power and efficiency, interchange crosstalk (Cc) attracting power penalties (Pc) are estimated and incorporated in the simulation for the real response of lossy SMF channel. Further, splitter power budget (SP) and slitter configuration for respective PtM and PtP D/L Ch are estimated under the aggregate impact of CD, SPM, XPM and FWM. Analytical modeling of LNI and simulative analysis has confirmed the configuration delivered rise in receiver sensitivity (Rxs) of - 39.75/- 33.45 dBm and - 29/- 35.34 dBm for D/L and U/L Ch respectively. The estimated power of FWM element is between 1.34 × 10-52 to 2.15 × 10-53 and 3.87 × 10-52 to 2.41 × 10-51 contributing crosstalk between Ch (Cc) of - 31.97/- 30.12 dB for down/up spectrum under the impact of SPM and XPM respectively accommodating splitter configuration of 768 at 40 km.

7.
Water Sci Technol ; 84(10-11): 2830-2841, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34850697

RESUMO

Superhydrophobic-superoleophilic fabrics were prepared and evaluated for oil-water mixture separation efficiencies. The nano-TiO2 and nano-SiO2 based coatings were done on the surface of the cotton fabric to create nanoscale roughness over the surface which was further modified by low energy material 1, 1, 3, 3-Hexamethyldisilazane (HMDS) and, polydimethylsiloxane (PDMS). Particle size and stability of prepared sol were characterized by particle size analysis and zeta potential. Coated cotton fabric samples were characterized by contact angle, contact angle hesteresis and surface free energy for its hydrophobic nature. Surface morphology was studied by scanning electron microscopy (SEM). The coated fabrics were found to be hydrophobic with low surface free energy values. The maximum contact angle was found to be 133° and lowest contact angle hysteresis was 5°. SEM confirmed the appearance of nanoscale surface roughness after coating of sols on cotton fabric. The average particle size and zeta potential values of silica sol was 61 nm and 137 mv whereas for titania sol it was found 344 nm and 200 mv, respectively. The oil-water separation efficiency of coated fabric was also observed by a different oil-water mixture. The coatings were found to be hydrophobic in nature and seem to be very useful for oil-water mixture separation.


Assuntos
Têxteis , Água , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Dióxido de Silício
8.
J Family Med Prim Care ; 8(1): 14-21, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30911475

RESUMO

The research study aimed to study the effect of short term exposure to light basically red, blue and white on the autonomic tone of essential hypertensive individuals. The objective was to find out the baseline cardiac autonomic function along with the effect of these lights on the cardiac autonomic function among them. Till date few if any study have been conducted upon the individuals with certain disorder as common as essential hypertension. This was a cross sectional observational study conducted in the institute itself that included 77 newly diagnosed hypertensive subjects who willingly participated in the study. After written informed consent, brief history taking with the help of self-made questionnaire and clinical examination, they were randomized to different intervention groups (IG) namely IG I (red) IG II (blue) and IG III (white). HRV analysis of the last 5-6 minutes of both the baseline and color exposure was finally analyzed using MS Excel version 13 and Graph Pad Prism version 7.05. Different HRV parameters have been found to be affected differently on different color exposures. Red has shown to have an impact, mainly on the sympathetic system whereas white showed a dominant vagal component thus acting as a parasympathetic regulator. On one hand, where no conclusive result was found on blue light exposure, white light showed the most prominent results affecting various time and frequency components of HRV like SDRR, TP, LF etc. The present study, both, contradicts as well as supports various other works done on the similar area of interest. One reason of such high variation in different results is because HRV is itself a very dynamic function affected by even a slight change in both the internal and external environment of the subject. As artificial lights of various colors are part and parcel of the aesthetics and designing of most of the work environment all over world, it is very pertinent to study its impact upon human health status. The outcome of the study may play a decisive role in the diagnostics and therapeutics of essential hypertension in days to come. Furthermore, on the basis of the present findings, a future study could be undertaken with bigger data base addressing the limitations of the present study to find some conclusive evidence in the area highlighted.

9.
J Mater Sci Mater Med ; 19(5): 2121-30, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17990082

RESUMO

Semi-interpenetrating polymer networks (IPNs) of carboxymethyl cellulose (CMC) and polyacrylic acid were prepared and its potential for controlled release of ciprofloxacine (Cfx) was assessed. The IPNs were characterized by IR spectral analysis and Environmental scanning electron microscopy (ESEM). The entrapped drug was examined for its antibacterial activity and chemical stability. The effects of experimental parameters such as varying chemical composition of the IPNs, percent loading of Cfx, pH and temperature of release medium and presence of salt ions in outer solution were examined on the release profile of the drug. On the basis of Fick's power law equations, the diffusion exponents (n) and diffusion constant (D) were evaluated for different IPNs compositions. From the kinetic parameter data, an attempt was made to resolve the mechanism of the release process of Cfx.


Assuntos
Carboximetilcelulose Sódica/farmacologia , Ciprofloxacina/administração & dosagem , Inibidores da Síntese de Ácido Nucleico/administração & dosagem , Resinas Acrílicas/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , Difusão , Relação Dose-Resposta a Droga , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Cinética , Teste de Materiais , Microscopia Eletrônica de Varredura , Polímeros/química , Espectrofotometria Infravermelho/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
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