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1.
Environ Res ; 244: 117921, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38101721

ABSTRACT

The novel glutamic acid crosslinked chitosan membrane (CsG) was fabricated and tested for its adsorption capabilities for the removal of multiple pollutants like Cr (VI), cyanide, fluoride and diclofenac sodium from wastewater. This fabricated CsG membrane was characterized by various techniques like FT-IR, SEM, EDX and XRD, BET to assess its structural, compositional and morphological properties. The working parameters studied by batch experiments were solution pH, CsG dose, contact time, pollutant concentration and solution temperature. The CsG membrane exhibited maximum adsorption capacity of 410.7 mg/g, 310.2 mg/g, 14.3 mg/g, 132.7 mg/g for Cr (VI), cyanide, fluoride and diclofenac respectively. The validation of the operational parameters was performed by Response Surface Methodology (RSM). The experimental data fitted well with Langmuir isotherm model and followed pseudo second order kinetics for all the four targeted contaminants. The spontaneity of the process was checked by thermodynamics studies. The high partition coefficients of 7669 L/kg Cr(VI), 23,309 L/kg (CN-), 649 L/kg (F-) and 2613 L/kg (DFC) are the indicators of excellent attractive interaction between CsG membrane and target toxicants. The CsG membrane showed efficient regenerative adsorption properties up to 5 adsorption-desorption cycles. Overall, the developed novel CsG membrane promised as an effective material for the removal of multiple number of pollutants from water.


Subject(s)
Chitosan , Environmental Pollutants , Water Pollutants, Chemical , Water Purification , Chitosan/chemistry , Glutamic Acid , Spectroscopy, Fourier Transform Infrared , Fluorides , Chromium/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Hydrogen-Ion Concentration , Thermodynamics , Adsorption , Kinetics , Cyanides
2.
Environ Res ; 261: 119698, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-39074773

ABSTRACT

One of the few elements that can have negative health impacts in both conditions, when consumed in excess or insufficiency is fluoride. In current study, aluminium magnetite alginate composite (AMA) was fabricated and applied using batch adsorption of fluoride as well as by using statistical modelling. Heterogeneous surface as revealed from scanning electron micrograph, thermal stability shown by thermal studies, high surface area of 29.77 m2 g-1, pore volume 0.1987 cm3 g-1 with mesoporous structure having average pore radius of 133 Å shown by BET analysis, fare degree of magnetization from VSM analysis were the important features of this material. Screening experiments and batch trials were carried out to obtain optimum working conditions. pH of 3.0, dosage of 50 mg, interaction period of 60 min and concentration of 50 mg L-1 depicted maximum defluoridation efficacy of about 94%. The adsorption capacity was found to be 60.08 mg g-1 in accordance with Langmuir adsorption isotherm, while pseudo second order kinetics was followed. Overall effects of various factors on sorption process were optimized using response surface methodology (RSM). Regeneration potential of AMA has been demonstrated for 10 adsorption-desorption cycles, showing more than 60% efficiency in tenth cycle. The AMA composite shows E-factor value 0.004 depicting it is sustainable in environment. In short, this novel composite showed excellent morphological, magnetic, functional properties that led to enhanced adsorption efficiency in short span of time that can be regenerated and reused in multiple cycles.


Subject(s)
Alginates , Aluminum , Ferrosoferric Oxide , Fluorides , Water Pollutants, Chemical , Water Purification , Alginates/chemistry , Fluorides/chemistry , Adsorption , Water Pollutants, Chemical/chemistry , Water Purification/methods , Aluminum/chemistry , Ferrosoferric Oxide/chemistry , Kinetics , Porosity
3.
Environ Res ; 252(Pt 1): 118764, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38527722

ABSTRACT

The primary aim of this research is to comprehensively assess the applicability of chitosan biopolymer towards water treatment application and to enhance its adsorption capacity towards Remazol brilliant blue R-19 dye. This has been achieved through physical modification to obtain the material in hydrogel form and chemical modification by crosslinking it with barbituric acid. The characterization of the resulting Chitosan-barbituric acid hydrogel (CBH) was carried out using various analytical techniques such as SEM-EDX, FT-IR, TGA-DTA, XRD, and BET. CBH was employed as the adsorbent to eliminate R-19 dye from aqueous media. Utilizing response surface methodology (RSM), the parameters were fine-tuned, leading to the achievement of more than a 95% removal for R-19 dye. The adsorption behavior closely adhered to the Langmuir isotherm and pseudo-second-order kinetics. An interesting observation indicated that the rise in temperature leads to rise in adsorption capacity of CBH. The maximum adsorption capacities evaluated at 301.15 K, 313.15 K, 318.15 K, and 323.15 K were 566.6 mg g-1, 624.7 mg g-1, 671.3 mg g-1, and 713.5 mg g-1 respectively, in accordance with the Langmuir isotherm model. Examining the thermodynamics of the adsorption process revealed its spontaneous nature (ΔG = -21.14 to -27.09 kJ mol-1) across the entire temperature range. Furthermore, the assessment of the isosteric heat of adsorption (ΔHads) was conducted using the Clausius-Clapeyron equation, with results indicating an increase in ΔHads from 1.85 to 2.16 kJ mol-1 with temperature rise from 301.15 K to 323.15 K due to augmented surface loading. This suggested the existence of lateral interactions between the adsorbed dye molecules. The potential of adsorbent for regeneration was investigated, demonstrating the ability to reuse the material. Sustainability parameter calculated for synthesis process reflected a notably low E-factor value of 0.32 demonstrated the synthesis is environment friendly.


Subject(s)
Chitosan , Water Pollutants, Chemical , Chitosan/chemistry , Adsorption , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/analysis , Hydrogels/chemistry , Anthraquinones/chemistry , Kinetics , Barbiturates/chemistry , Water Purification/methods , Coloring Agents/chemistry
4.
Environ Res ; 242: 117762, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38029812

ABSTRACT

The objective of this research is to conduct a comprehensive characterization of chitosan while also improving its attributes by crosslinking with malonic acid, with a focus on its efficacy in removing hexavalent chromium, arsenite and fluoride ions. Crosslinking chitosan in 1:0.5 mass ratio forming a film led to substantial enhancement in confiscation of these target pollutants. The characterization of the adsorbent involved several techniques, including FT-IR, TGA-DSC, SEM-EDX, XRD, and BET surface area analysis. In batch adsorption experiments, Chitosan-malonic acid (CMA) was employed to remove CrVI, AsIII and F- from aqueous solutions. These experiments were conducted while varying conditions such as pH, dosage, concentration, temperature, and time. Through the implementation of response surface methodology (RSM), parameters were optimized, resulting in over 95% removal of CrVI, AsIII and F- ions. The isotherm and kinetics data demonstrated a good fit with the Langmuir isotherm model and pseudo second-order kinetics, respectively. According to the Langmuir isotherm, the maximum adsorption capacities on CMA for CrVI, AsIII and F- were determined to be 687.05 mg g-1, 26.72 mg g-1 and 51.38 mg g-1 respectively under optimum pH of 4.0, 7.0 and 5.0 respectively under ambient temperature of 303 K. Thermodynamic analysis indicated that the adsorption process was spontaneous and driven by enthalpy. The regenerability of the adsorbent was validated through five adsorption-desorption cycles, signifying its reusability. An assessment of the adsorbent's sustainability indicated an eco-friendly synthesis, as reflected by the low E-factor value of 0.0028.


Subject(s)
Chitosan , Malonates , Water Pollutants, Chemical , Water Purification , Chitosan/chemistry , Spectroscopy, Fourier Transform Infrared , Adsorption , Water Pollutants, Chemical/chemistry , Water Purification/methods , Thermodynamics , Chromium/chemistry , Kinetics , Ions , Hydrogen-Ion Concentration
5.
Environ Res ; 251(Pt 2): 118770, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38518913

ABSTRACT

Multifunctional nanoparticles (NPs) production from phytochemicals is a sustainable process and an eco-friendly method, and this technique has a variety of uses. To accomplish this, we developed zinc oxide nanoparticles (ZnONPs) using the medicinal plant Tinospora cordifolia (TC). Instruments such as UV-Vis, XRD, FTIR, FE-SEM with EDX, and high-resolution TEM were applied to characterize the biosynthesized TC-ZnONPs. According to the UV-vis spectra, the synthesized TC-ZnONPs absorb at a wavelength centered at 374 nm, which corresponds to a 3.2 eV band gap. HRTEM was used to observe the morphology of the particle surface and the actual size of the nanostructures. TC-ZnONPs mostly exhibit the shapes of rectangles and triangles with a median size of 21 nm. The XRD data of the synthesized ZnONPs exhibited a number of peaks in the 2θ range, implying their crystalline nature. TC-ZnONPs proved remarkable free radical scavenging capacity on DPPH (2,2-Diphenyl-1-picrylhydrazyl), ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid), and NO (Nitric Oxide). TC-ZnONPs exhibited dynamic anti-bacterial activity through the formation of inhibition zones against Pseudomonas aeruginosa (18 ± 1.5 mm), Escherichia coli (18 ± 1.0 mm), Bacillus cereus (19 ± 0.5 mm), and Staphylococcus aureus (13 ± 1.1 mm). Additionally, when exposed to sunlight, TC-ZnONPs show excellent photocatalytic ability towards the degradation of methylene blue (MB) dye. These findings suggest that TC-ZnONPs are potential antioxidant, antibacterial, and photocatalytic agents.


Subject(s)
Anti-Bacterial Agents , Antioxidants , Green Chemistry Technology , Zinc Oxide , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Zinc Oxide/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Green Chemistry Technology/methods , Catalysis , Metal Nanoparticles/chemistry , Nanoparticles/chemistry
6.
Environ Monit Assess ; 196(7): 646, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38907046

ABSTRACT

The study of natural disasters is a crucial field that involves analyzing the occurrence, impact, and aftermath of various natural hazards that can cause significant harm to communities and the environment. Efficient waste management and environmental protection require proper classification of waste. Analyzing natural disasters and categorizing waste can be a time-consuming task, and conventional methods often struggle with it. However, a new approach called Visual Geometry Group with Federated Learning (VGG-FL) has been introduced to address these challenges. This methodology uses the golden search optimization (GSO) algorithm for feature selection and leverages VGG with federated learning for feature extraction and classification. To test the effectiveness of this method, a disaster image dataset was used to train the VGG-FL model. The results showed that the VGG-FL model attained exceptional accuracy in discerning and categorizing various disaster scenarios. The waste classification dataset simultaneously trains the VGG-FL model to categorize waste based on its characteristics and potential hazards. To measure the model's performance, several evaluation metrics such as accuracy, specificity, precision, F1-score, and recall are utilized to assess the effectiveness of the proposed VGG-FL method. These results are then compared with existing methodologies. The VGG-FL method performs exceptionally well, achieving 98.52% accuracy, 97.48% precision, 97.83% recall, 97.58% F1-score, and 97.12% specificity. These experimental findings demonstrate the efficacy of the VGG-FL method in analyzing natural disasters and classifying waste materials.


Subject(s)
Algorithms , Natural Disasters , Machine Learning , Waste Management/methods , Environmental Monitoring/methods
7.
ScientificWorldJournal ; 2016: 6105053, 2016.
Article in English | MEDLINE | ID: mdl-27006976

ABSTRACT

Today's technology development in the field of computer along with internet of things made huge difference in the transformation of our lives. Basic computer framework and web client need to make significant login signify getting to mail, long range interpersonal communication, internet keeping money, booking tickets, perusing online daily papers, and so forth. The login user name and secret key mapping validate if the logging user is the intended client. Secret key is assumed an indispensable part in security. The objective of MFA is to make a layered safeguard and make it more troublesome for an unauthenticated entity to get to an objective, for example, a physical area, processing gadget, system, or database. In the event that one element is bargained or broken, the assailant still has two more boundaries to rupture before effectively breaking into the objective. An endeavor has been made by utilizing three variable types of authentication. In this way managing additional secret key includes an additional layer of security.

8.
Water Sci Technol ; 70(12): 2047-55, 2014.
Article in English | MEDLINE | ID: mdl-25521142

ABSTRACT

A sulfate-crosslinked chitosan (SCC) was prepared for effective detoxification of hexavalent chromium (Cr(VI)) from effluents. SCC was characterized using Fourier transform infrared, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray studies. The maximum adsorption of Cr(VI) was observed at pH 6.0 with adsorption capacity of 157 mg/g in accordance with the Langmuir adsorption isotherm model. The adsorption process was found to follow the pseudo-second-order rate kinetics. From the study of various thermodynamic parameters (Gibbs energy, entropy and enthalpy changes), the adsorption capacity was found to decrease with increase in temperature. Column studies were carried out to obtain a breakthrough point of the adsorbent. The adsorbent was regenerated using sodium hydroxide with no change in the adsorption efficiency for up to 10 cycles. Effect of diverse ions on adsorption efficiency was studied and SCC was applied for Cr(VI) removal in synthetic effluents.


Subject(s)
Chitosan/chemical synthesis , Chromium/isolation & purification , Adsorption , Environmental Pollution/prevention & control , Hydrogen-Ion Concentration , Ions , Kinetics , Microscopy, Electron, Scanning , Sulfates , Temperature , Thermodynamics , Waste Disposal, Fluid , X-Ray Diffraction
9.
Open Life Sci ; 18(1): 20220770, 2023.
Article in English | MEDLINE | ID: mdl-38045489

ABSTRACT

Cervical cancer is one of the most dangerous and widespread illnesses afflicting women throughout the globe, particularly in East Africa and South Asia. In industrialised nations, the incidence of cervical cancer has consistently decreased over the past few decades. However, in developing countries, the reduction in incidence has been considerably slower, and in some instances, the incidence has increased. Implementing routine screenings for cervical cancer is something that has to be done to protect the health of women. Cervical cancer is famously difficult to diagnose and cure due to the slow rate at which it spreads and develops into more advanced stages of the disease. Screening for cervical cancer using a Pap smear, more often referred to as a Pap test, has the potential to detect the illness in its earlier stages. For the purpose of selecting features for this article, a gray level co-occurrence matrix (GLCM) technique was used. Following this step, classification is performed with methods such as convolutional neural network (CNN), support vector machine, and auto encoder. According to the findings of this experiment, the GLCM-CNN classifier proved to be the one with the highest degree of precision.

10.
Nat Prod Res ; 37(4): 681-686, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35608174

ABSTRACT

In this contribution, ethanolic extracts of Cuminum cyminum (C. cyminum) seeds were evaluated in terms of phytochemical content, total phenol and flavonoid contents. As far as the analytical techniques are concerned, UV-Vis, FTIR, HPLC, NMR (1H and 13C) and ESI-MS were performed. The binding capacity of five different antidiabetic enzymes was tested by in silico molecular docking studies. The HPLC, UV-Vis, FTIR, NMR and ESI-MS data highlighted the presence of seven biologically active molecules e.g. α-pinene, ß-pinene, Δ3-carene, ρ-cymene, α-terpineol, cuminaldehyde and linalool. The results coming from the in silico molecular docking studies showed that such phytochemicals present in the cumin seed extracts play an important role in the activity of key enzymes involved in carbohydrate metabolism. Therefore, C. cyminum is proven to be useful for the treatment of diabetes mellitus and its major secondary complications.


Subject(s)
Cuminum , Hypoglycemic Agents , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/analysis , Cuminum/chemistry , Molecular Docking Simulation , Phytochemicals/pharmacology , Phytochemicals/analysis , Plant Extracts/chemistry , Seeds/chemistry
11.
Procedia Comput Sci ; 215: 706-712, 2022.
Article in English | MEDLINE | ID: mdl-36618030

ABSTRACT

The Covid-19 (coronavirus) pandemic creates a worldwide health crisis. According to the WHO, the effective protection system is wearing a face mask in public places. Many studies proved that carrying a face mask is also one of the precautions to decrease the possibility of viral transmission. Strict monitoring of face mask being worn by people is now enforced in many countries. Manual observation and monitoring is quite tedious. Hence, automated systems have been researched using well-kwown face mask detection methods. However, this research paper, deals with some deep learning models which can be effectively used to detect multiple face masks in a crowded environment when the amount of incoming data from sensors is huge or in otherwise stated to a Big data problem. Hence, standalone face detection models are not quite suited. Deep learning models are required in such Big data scenario which forms the essence of this study.

12.
Int J Biol Macromol ; 223(Pt A): 636-651, 2022 Dec 31.
Article in English | MEDLINE | ID: mdl-36370863

ABSTRACT

The aim of the study is to characterize and hierarchically modify chitosan using partially lateritized khondalite (PLK) rock. PLK is a metamorphic rock rich in mineral oxides and is not commercialized thus, treated as a mining reject. Chitosan was sequentially altered to Chitosan-PLK (Ch-PLK) and Chitosan-PLK-Epichlorohydrin (Ch-PLK-ECH) and both the materials were characterized by FT-IR, SEM, EDX, XRD, XRF and BET surface area analysis. The adsorbents were used for removal of cyanide ions from aqueous solution using batch adsorption experiments. The experiments were performed varying operational parameters and were optimized using RSM. The conditions optimized by RSM were carried out, more than 90 % of CN- adsorption was observed. The isotherm and kinetics studies have shown that the adsorption process fitted well with Langmuir isotherm model and pseudo second order kinetics. Using Langmuir isotherm, the maximum adsorption capacities of Ch-PLK and Ch-PLK-ECH towards cyanide ions at 30 °C were found to be 23.98 mg g-1 and 65.27 mg g-1 respectively. Thermodynamic studies described that adsorption process was spontaneous, enthalpy-driven over entire temperature range. Column studies established that the adsorbents may be applicable to large volume of samples. The adsorbents were tested for regeneration for 5 adsorption-desorption cycles suggesting reusability of the materials.


Subject(s)
Chitosan , Water Pollutants, Chemical , Water Purification , Cyanides , Spectroscopy, Fourier Transform Infrared , Hydrogen-Ion Concentration , Temperature , Adsorption , Kinetics , Thermodynamics
13.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2612, 2011 Oct 01.
Article in English | MEDLINE | ID: mdl-22058758

ABSTRACT

In the title compound, C(11)H(9)ClN(4)OS(2), the thia-diazole and chloro-phenyl rings are oriented at an angle of 43.1 (1)°. The sum of the bond angles around the amide N atom (359.8°) of the acetohydrazide group is in accordance with a model of sp(2) hybridization. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R(2) (2)(8) loops. Weak C-H⋯π inter-actions also occur.

14.
3 Biotech ; 11(12): 490, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34790514

ABSTRACT

The objective of this study was to develop nanobiomaterial containing silver nanoparticles (AgNPs) for wound healing. AgNPs were synthesized using Saussurea lappa (Sl) aqueous root extract as reducing agent and were characterized physico-chemically using UV-vis spectral studies, XRD, FESEM, TEM, FTIR spectral analysis, DLS, and TG-DSC. Sl AgNPs production was optimized using response surface methodology. The cytotoxicity of Sl AgNPs was assessed by THP1 cell lines, which showed that Sl AgNPs were nontoxic with an IC50 of 151.10 µg/mL at 24 h. For topical application, Sl AgNPs was loaded on chitosan hydrogel was characterized through spreadability, in vitro release, antibacterial activity, swelling behavior, and SEM analysis. The chitosan Sl AgNPs hydrogel was subjected acute dermal toxicity test using Wistar albino rats and was found to be nontoxic. The excisional wound model was created along with Pseudomonas aeruginosa as an inoculant in Wistar albino rats. The chitosan Sl AgNPs hydrogel treated rats showed excellent wound healing qualities, lower bacterial counts, and enhanced production of connective tissues. Our findings strongly suggest that AgNPs synthesized from Saussurea lappa root extract loaded on chitosan hydrogel possibly applied for the remedy of infectious wounds at a concentration of 0.1 mg of Sl AgNPs/g of hydrogel. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-03030-0.

15.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): o998, 2010 Mar 31.
Article in English | MEDLINE | ID: mdl-21580794

ABSTRACT

In the title compound, C(33)H(34)N(6)O(6), the dihydro-benzimidazol-2-one ring system is essentially planar (r.m.s. deviation = 0.021 Å). The cyclo-hexane ring adopts a chair conformation. In the 5-(biphenyl-2-yl)-2H-tetra-zole fragment, the tetra-zole ring is twisted away from the attached benzene ring by 35.73 (11)° and the two benzene rings form a dihedral angle of 68.00 (9)°. An intra-molecular C-H⋯O inter-action is observed. In the crystal, the mol-ecules are linked into a zigzag chain running along the b axis by inter-molecular N-H⋯O hydrogen bonds.

16.
J Pharm Biomed Anal ; 47(1): 183-9, 2008 May 12.
Article in English | MEDLINE | ID: mdl-18313249

ABSTRACT

The focus of this study is identification, isolation and characterization of a principal oxidation impurity of clopidogrel which ranged from 0.05 to 0.12% using high performance liquid chromatography. This impurity is considered as principal oxidation impurity as it is observed in oxidative degradation (stress) study. Preparative HPLC with Xterra MS C18 ODB column was used to isolate the impurity. The isolated impurity was co-injected with the sample containing impurities and found the retention time match of the spiked impurities. A thorough study was undertaken to characterize this impurity and based on their spectral data (UV, MS, MSn 1H/13C, DEPT and 2D NMR) the structure was characterized as 5-[1-(2-chlorophenyl)-2-methoxy-2-oxoethyl]-6,7-dihydrothieno[3,2-c]pyridin-5-ium with a molecular weight 320 amu.


Subject(s)
Drug Contamination , Pharmaceutical Preparations/analysis , Platelet Aggregation Inhibitors/analysis , Ticlopidine/analogs & derivatives , Clopidogrel , Magnetic Resonance Spectroscopy , Oxidation-Reduction , Spectrometry, Mass, Electrospray Ionization , Ticlopidine/analysis , Ticlopidine/chemistry
17.
J Photochem Photobiol B ; 171: 20-26, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28472721

ABSTRACT

The flavonoids present in the leaves of Lagerstroemia speciosa were extracted, characterized by spectral methods and studied for its cytotoxicity activity against MCF-cell lines and photocatalytic activity against azo dye. Direct and sequential soxhlet extraction was performed and its concentrated crude extract was subjected to high performance liquid chromatography. The yield obtained by the isolated compound (MEI-quercetin) from leaves of L. speciosa was found to be 1.8g from the methanolic extract. The phytochemical analysis and the Rf value of the isolated flavonoid was found to be 3.59. The isolated compound was characterized by Infrared Spectroscopy, NMR and Mass. Based on the characterization, the structure was elucidated as quercetin - a flavonoid. The isolated compound showed the significant in vitro cytotoxicity activity against MCF-7 cell lines at 500µg/ml when compared to the crude extract. Among the various concentrations (25, 50, 100, 250, and 500µg/ml), at higher concentration the cell viability was pronounced and also compared with that of the control. It was first time to report that the isolated flavonoid showed photocatalytic against azo dye-methyl orange. The dye degradation was monitored by UV-Vis spectrophotometry. The isolated compound showed dye degradation of 91.66% with the crude extract 82.47% at 160min. Hence in the present findings, the photocatalytic degradation of MO dye under UV irradiation was investigated over isolated compound of L. speciosa. Hence we expect that this can be used to treat the waste water in near future based on the photocatalytic technique.


Subject(s)
Lagerstroemia/chemistry , Plant Extracts/chemistry , Azo Compounds/chemistry , Azo Compounds/metabolism , Azo Compounds/toxicity , Catalysis , Cell Survival/drug effects , Cell Survival/radiation effects , Chromatography, High Pressure Liquid , Humans , Lagerstroemia/metabolism , Light , MCF-7 Cells , Magnetic Resonance Spectroscopy , Mass Spectrometry , Methanol/chemistry , Photolysis/radiation effects , Plant Leaves/chemistry , Plant Leaves/metabolism , Quercetin/analysis , Quercetin/isolation & purification , Quercetin/toxicity , Spectrophotometry, Ultraviolet
18.
Int J Biol Macromol ; 104(Pt B): 1528-1538, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28259624

ABSTRACT

Chitosan, a potent amino polysaccharide, has been impregnated with Sn(IV) chloride for effective adsorption of fluoride from water. The Sn(IV) chloride impregnated chitosan was synthesized using microwave assisted technique. The material was thoroughly characterized using FTIR, SEM, EDX and XRD. The decrease in surface area and pore volume has been revealed from BET studies. Enhanced thermal stability of this material was ascertained by TGA-DTA studies. This Sn(IV) chloride impregnated chitosan(Sn-Ch) has been exploited for its defluoridation property. Various parameters like pH, amount of adsorbent, adsorption time etc have been optimized to achieve maximum defluoridation efficiency. Under optimum conditions, Sn-Ch was found to have adsorption capacity of 17. 63mg/g. The equilibrium studies showed that the data fits well with Freundlich isotherm model. Thermodynamics and kinetics parameters have been evaluated. The material has been applied for the defluoridation of real water sample. It was found to be recyclable material and can be regenerated and reused multiple times adding a greener dimension.


Subject(s)
Chitosan/chemistry , Fluorides/chemistry , Tin Compounds/chemistry , Water Purification/methods , Water/chemistry , Adsorption , Fluorides/isolation & purification , Kinetics
19.
Carbohydr Polym ; 172: 205-212, 2017 Sep 15.
Article in English | MEDLINE | ID: mdl-28606527

ABSTRACT

Chitosan, a potent amino polysaccharide, has been cross-linked with Sn(IV) chloride. The material was thoroughly characterized using FT-IR, XRD, SEM, EDX, TGA-DTA and BET studies. This Sn(IV) chloride cross-linked chitosan (Sn-Ch) has been exploited for As(III) adsorption. Various parameters like pH, amount of adsorbent, adsorption time etc have been optimized to achieve maximum adsorption efficiency. Under optimum conditions of pH 7.0±0.2, adsorption time of 45min and adsorbent dose 200mg, Sn-Ch was found to have adsorption capacity of 17.10mg/g at 298K. Adsorption of As(III) by Sn-Ch follow non-linear Freundlich isotherm model. The equilibrium studies showed that the experimental data fits well with non-linear pseudo-second-order kinetic model. Adsorption process was found to be exothermic and spontaneous. Column study proves the applicability of Sn-Ch to the larger sample volumes. It was found to be recyclable material and could be regenerated and reused multiple times adding a greener dimension.

20.
Int J Biol Macromol ; 104(Pt B): 1556-1568, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28214584

ABSTRACT

Ethylhexadecyldimethyl ammonium bromide impregnated chitosan (EHDAIC) was prepared to remove cadmium and mercury from synthetic effluent. The adsorbent was characterized by FTIR, XRD, SEM, EDX and TGA-DTA. Adsorption studies were carried out under different conditions of pH, adsorbent dose, temperature, and contact time. The results showed that the adsorption capacity of EHDAIC is a function of the solution pH and the optimum pH for these metal ions was found to be 3.0. The equilibrium data has been described using Langmuir and Freundlich isotherm models. The maximum adsorption capacity of 341.30mg/g was observed for Cd(II) and 43.43mg/g for Hg(II) in accordance with Langmuir adsorption isotherm in the form of their chloro complexes. The kinetic data fitted well with pseudo-second-order model, and equilibrium data was found to follow Freundlich isotherm model. The calculated thermodynamic parameters showed that the adsorption process was feasible, exothermic and spontaneous. Effect of common excipient ions was studied. Also the material was tested for large sample volumes using column extraction process. The adsorbent material could be regenerated for repetitive applications.


Subject(s)
Cadmium/chemistry , Cadmium/isolation & purification , Chitosan/chemistry , Environmental Pollutants/chemistry , Environmental Pollutants/isolation & purification , Mercury/chemistry , Mercury/isolation & purification , Adsorption , Hydrogen-Ion Concentration , Kinetics , Quaternary Ammonium Compounds/chemistry
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