The mechanism of adsorption of p-cresol over activated carbon adsorbent and the specific role of ... more The mechanism of adsorption of p-cresol over activated carbon adsorbent and the specific role of oxygen functional groups on cresol adsorption were studied using density functional theory (DFT) calculations. All the energy calculations and geometry optimization pertaining to DFT calculations were done using the B3LYP hybrid functional at basis set 6-31g level of theory in a dielectric medium of ε = 80 (corresponding to water). The interaction of cresol with different activated carbon models, namely pristine activated carbon, hydroxyl functionalized activated carbon, carbonyl functionalized activated carbon, and carboxyl functionalized activated carbon, were considered, and their adsorption energies corresponded to −416.47 kJ/mol, −54.73 kJ/mol, −49.99 kJ/mol, and −63.62 kJ/mol, respectively. The high adsorption energies suggested the chemisorptive nature of the cresol-activated carbon adsorption process. Among the oxygen functional groups, the carboxyl group tended to influence the ...
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
When polymeric materials like Polyallyl diglycol carbonate (PADC), Polycarbonate (PC), Polyvinyl ... more When polymeric materials like Polyallyl diglycol carbonate (PADC), Polycarbonate (PC), Polyvinyl Chloride (PVC), Polypropylene (PP) etc. are exposed to gamma radiation, they show pronounced changes in their physical and chemical properties. Interestingly, the changes due to irradiation are varied in nature, proving that all polymers do not undergo similar type of modifications under similar irradiation conditions. Thus, while polymers like PADC and PVC do not reveal any change in the IR spectral pattern, the IR spectrum of polypropylene polymer confirms the total destruction of isotactic arrangements of the polymer leading to the formation of alcoholic and ketonic groups. The etch-rates are drastically enhanced due to irradiation at the highest dose for all types of PADC detectors which is not the case for polycarbonates. For polyacetate polymer, elimination of carbon dioxide takes place due to destruction of the ester group. Interestingly, in polycarbonate polymer it was observed t...
A new application of nuclear track microfilters has been demonstrated by determining the critical... more A new application of nuclear track microfilters has been demonstrated by determining the critical micelle concentration (CMC) of cationic, anionic and nonionic surfactants. The lowering of CMC due to the addition of methyl red dye in Trition X-100 surfactant (in molar ratio of 1:100) has also been studied. The critical micelle concentrations of cetyl pyridinium chloride (CPC), sodium dodecyl sulphate (SDS) and polyoxyethylene (9.5) octylphenol (Triton X-100) surfactants are determined using polycarbonate nuclear track microfilters and these are found to be comparable with the literature values. The experimental method is described here and the results are discussed.
Investigations are made on the removal of fluoride from water by prepared activated carbons. Thre... more Investigations are made on the removal of fluoride from water by prepared activated carbons. Three activated carbon adsorbents, BKC, BOC and RSC are prepared from selected biomaterials of bergera koenigh, batavia orange and raphanus sativus respectively. The adsorption capacity towards adsorption of fluoride from aqueous solution was studied and was determined by using fixed amount of adsorbent(0.1g/100mL) and a known concentration of adsorbate (5mg/L) solution at 30 minutes agitating time. The data have been analyzed in the light of adsorption isotherms, adsorption kinetic equations and intraparticle diffusion model. Regeneration of adsorbents was studied.
In this work, the synthesis, characterization, and photocatalytic activity of iron-doped titaniu... more In this work, the synthesis, characterization, and photocatalytic activity of iron-doped titanium dioxide nanoparticles (FDT) supported on environmentally benign activated carbon (PAC) has been discussed. The photocatalytic activity of the nanocomposite was investigated for the degradation of Congo red (CR) dye from aqueous solution under visible light (520 nm), and it was observed that 100% degradation for 20 ppm CR solution took place within 60 mins. The experimental data of photodegradation of CR using the FDT/PAC nanocomposite had the highest correlation with Langmuir Hinshelwood model and pseudo-first-order rate kinetics with an apparent rate constant of 0.05341 min 1 and half-life period of 12.97 mins, respectively. The thermodynamics study revealed that the degradation process is exothermic and spontaneous. The effect of interfering ions on the degradation of CR solution was also examined. The photocatalytic antibacterial activity of the nanocomposite was tested against two bacteria pathogens, Escherichia coli and Staphylococcus aureus, and it was found that for the concentration of 10 5 CFU ml 1 , 100% photocatalytic inactivation was achieved for both Escherichia coli in 120 mins and Staphylococcus aureus in 75 mins under visible light irradiation. The total electrical energy consumed and operating cost were measured and the total operating cost was 312.50, 236.74, and 166.67 INR (Indian rupee) for 20 ppm, 60 ppm, and 100 ppm CR dye removal using 0.06 g FDT/PAC nanocomposite, respectively.
Activated carbon was synthesized from Tithonia diversifolia biomass using potassium hydroxide as ... more Activated carbon was synthesized from Tithonia diversifolia biomass using potassium hydroxide as the chemical activating reagent. Taguchi's experimental design approach was applied to determine the best preparation conditions. An optimum 2:1 impregnation ratio and 700°C activation temperature produced the best carbon with a high 854.44 m 2 g-1 surface area, 0.445 cm 3 g-1 total pore volume and 18.3% yield. From the analysis of variance (ANOVA), the impregnation ratio was found to be the most influential factor in preparing activated carbon with the maximum surface area. SEM and XRD studies revealed the porous microcrystallite structure of the obtained activated carbon. Batch adsorption studies were performed to test the efficiency of Tithonia diversifolia activated carbon for the removal of Bisphenol A (BPA) from aqueous solution. A maximum 98.2% removal percentage was attained at optimum conditions of 0.2 g adsorbent dose, pH 7, 80 min contact time and 40 mg L −1 initial BPA concentration. The Langmuir isotherm model described the equilibrium adsorption of BPA well with a maximum adsorption capacity(q m) of 15.69 mg g −1 while the kinetic adsorption study indicated a pseudo second order model. A theoretical investigation suggested that the adsorption of BPA onto the activated carbon mainly proceeds via chemisorption and the presence of a carboxyl functional group on the activated carbon surface yielded a greater adsorptive impact on BPA. This study indicates that Tithonia diversifolia could be used as a potential raw material for preparing activated carbon for removing of BPA from water.
Waterborne pathogens in drinking water affect the lives of millions worldwide especially in the r... more Waterborne pathogens in drinking water affect the lives of millions worldwide especially in the rural areas of developing countries. Access to clean drinking water and modern water purification system is rare in rural community, therefore low maintenance, cost-effective and easy operational point-of-use water purification methods need to be employed to improve the quality of water in rural areas. Thus, the present manuscript gives an idea of the different techniques employed and use of ecofriendly, sustainable and cheap resources for effective removal of pathogens.
Water is a vital resource for sustaining life, however in present scenario the access to clean sa... more Water is a vital resource for sustaining life, however in present scenario the access to clean safe water around the world has become a burning concern especially in developing and emerging countries attributing to increase in population, climate change and environmental water pollution by sewages, industrial effluents, chemicals, domestic wastes, pesticides, pharmaceuticals and so on. These pollutants consist of organic, inorganic, biological and radioactive substances that make the water unfit for any use and poses a threat to human health, animals and plants as they are either toxic, carcinogenic or mutagenic. 1−3 According to report of World Water Development 2017, currently only 20% of wastewater produced globally receives proper treatment while majority of it is discharged without any form of treatment into the environment. 4 The occurrence of organic pollutants in wastewater have increased tremendously in modern years and has become a critical concern because of their toxicity, semi volatile nature, low water solubility, high bioaccumulation and non-biodegradability under normal environmental condition. 5-7 These types of organic pollutants such as phenolic compounds, polycyclic aromatic hydrocarbons (PAHs) and agricultural chemicals (organic pesticides and organic herbicides) have been considered as critical problems as it leads to aquatic system depletion, environmental degradation and also affect human health such as reproductive system disorders, endocrine disruption, obesity and cancer. 8,9 In this regard, water purification have now become the main critical issue worldwide for which strict legislation has been formulated by World Health Organization for organic compounds for Drinking-Water Quality. 10,11 Many ongoing studies in water purification remain a severe challenge to governments, scientists and industries, as lack of cost-effective water purification technology has aggravated the crisis of clean and safe water for the fast expanding population. Over the years, various methodologies to remediate these water threats have been developed, such as photocatalytic degradation, 12 advanced oxidation, 13 micellar enhanced ultra filtration, 14 combined photo-fenton and ultrasound,
The experimental results on the characterization of three polymeric solids in terms of energy-los... more The experimental results on the characterization of three polymeric solids in terms of energy-loss of 20-80 MeV t2C ions m Kapton, Hostaphan and Makrofol-N have been presented and compared with theoretical values.
Activated carbon synthesized from the plant Mucuna prurines have been successfully used to remove... more Activated carbon synthesized from the plant Mucuna prurines have been successfully used to remove fluoride from aqueous solution by adsorption method. Batch method adsorption has been studied and the adsorption was found to be very significant. Almost 96% of fluoride could be removed by adsorption. Adsorption studies of fluoride signify the fact that among the different adsorption model, Langmuir adsorption model seems to be more favorable in the present case. Different parameters like effect of adsorbent dosage, contact time, pH and initial concentration are studied to understand the adsorption mechanism.
Chitosan is known for its absorption and adhesion property and it is a non-toxic biodegradable he... more Chitosan is known for its absorption and adhesion property and it is a non-toxic biodegradable hetero polymer. It has a strong affinity for water and high degree of solubility in acidic medium. In addition, chitosan hydrogels showed low mechanical strength and minimum ability to control the delivery of encapsulated compounds. And hence, in this investigation a set of compounds cross linked with Chitosan was screened for anticancer agent using computational technique (molecular docking) against NOS enzyme (PDB ID: 4NOS). The result was interesting as majority of the compounds screened turned up with favorable molecular interaction and binding affinity as evidenced from the docking score. Furthermore the molecular interaction analysis represents the cross linked compounds possessed heavy molecular interaction at the active site residue of the enzyme. Thus, Chitosan cross linked compounds target the specific active site residue and hence can be used in future for drug delivery.
Gamma irradiation effects on track properties of Polyallyl Diglycol Carbonate (PADC) track detect... more Gamma irradiation effects on track properties of Polyallyl Diglycol Carbonate (PADC) track detector (PADC-American Acrylics) are studied in the dose range of 101-106Gy. It is observed that due to gamma exposure the bulk and track-etch rates of the detector increases. This increase in both etch-rates is more pronounced in post gamma exposed PADC detectors. The etch-rate ratio (S) for both pre and post-gamma exposed detectors decreases with increasing etching temperature at the dose of 106Gy. At a higher etching temperature of 70ºC, the etch rates ratio becomes almost equal for post gamma exposed detector. Etching efficiency of the detector is found to be much higher when exposed to gamma radiation. However it is observed that at the etching temperature of 70ºC, etching efficiency for both pre and post-gamma exposed samples tends to become almost equal to the pristine one.
Microwave-induced solvent-free brominations of organic substrates have been carried out with tetr... more Microwave-induced solvent-free brominations of organic substrates have been carried out with tetrabutylammonioum tribromide,(C4H9) 4N+(Br3–). Reactions are facile, affording products in high yields within very short reaction times. Keywords: Microwave ( ...
... DOI: 10.1080/00397910903531912 Latonglila Jamir a , B. Alimenla a , Anil Kumar a , Dipak Sinh... more ... DOI: 10.1080/00397910903531912 Latonglila Jamir a , B. Alimenla a , Anil Kumar a , Dipak Sinha a ... 2006 , 161 , 687 – 693 ; (l) Alimenla , B. ; Kumar , A. ; Jamir , L. ; Sinha , D. ; Sinha , UB An ... Nath , J. ; Ghosh , H. ; Yella , R. ; Patel , BK Molecular iodine–mediated preparation of ...
E ect of gamma irradiation on thermal properties of di erent types of nuclear track detectors lik... more E ect of gamma irradiation on thermal properties of di erent types of nuclear track detectors like PADC (Homalite), PADC (American-Acrylics), Polycarbonate, Lexan, Makrofol-E, Triafol-TN, Triafol-BN and Polypropylene are studied in the dose range of 10 1-10 6 Gy. For some detectors like PADC (Homalite), Lexan and Makrofol-E, the e ect is not very signiÿcant. But for detectors like PADC (American-Acrylics), the thermal resistance comes down at a dose of 10 6 Gy and the detector decomposes at much lower temperatures. Polycarbonate detectors gain some thermal stability due to gamma exposure at the highest dose. In the case of polypropylene detectors, the thermal stability decreases drastically and the detector decomposes in four di erent steps in comparison to single-step decomposition shown by the pristine one.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2005
Ion irradiation of polymers offers a number of interesting possibilities for applications. In the... more Ion irradiation of polymers offers a number of interesting possibilities for applications. In the case of latent tracks, radiochemical changes, phase transitions, alterations of the intrinsic free volume, or radiation induced defects can be exploited-the latter ones to trap mobile impurities. These approaches are useful to form, e.g. new types of sensors. Apart from this, etched tracks in polymers offer a vast range of possibilities. Practically any material-including colloides and nanocrystals-can be inserted into these pores to form nanowires or nanotubules. Sequential deposition can be made as well in radial as axial direction to form complex nanostructures. Combination with lithography enables one to form different types of novel transistors, microcapacitors,-magnets,-transformers and-sensors. Also sterilizing foils for medicine and packing industry have been made in this way. A number of new ideas are presented how to proceed further in this field.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2000
Ion beam treatment studies have been carried out to investigate the potential for improvements in... more Ion beam treatment studies have been carried out to investigate the potential for improvements in conductivity properties of the polymers Polytetra¯uroethylene (PTFE), Polyimide (PI), Polyethyleneterepthalate (PET) and Polypropylene (PP), after 2 MeV electron and 62 MeV proton irradiation. The shift in optical absorption edges as observed by UV±VIS spectra of the irradiated polymers has been correlated to the optical band-gap using TaucÕs expression. A decrease in the optical band-gap has been observed in irradiated PP and PTFE, but no considerable change was found for the optical band-gaps of PET and PI. Further AC conductivity measurements con®rmed an increase in conductivity in electron irradiated PP.
The efficacies of different organic ammonium tribromides were studied with different classes of o... more The efficacies of different organic ammonium tribromides were studied with different classes of organic substrates using solvent-free reaction protocols involving reactions at elevated temperature and also under microwave conditions. The reactions were regio-selective, facile and afforded good to excellent product yields in short reaction time.
The mechanism of adsorption of p-cresol over activated carbon adsorbent and the specific role of ... more The mechanism of adsorption of p-cresol over activated carbon adsorbent and the specific role of oxygen functional groups on cresol adsorption were studied using density functional theory (DFT) calculations. All the energy calculations and geometry optimization pertaining to DFT calculations were done using the B3LYP hybrid functional at basis set 6-31g level of theory in a dielectric medium of ε = 80 (corresponding to water). The interaction of cresol with different activated carbon models, namely pristine activated carbon, hydroxyl functionalized activated carbon, carbonyl functionalized activated carbon, and carboxyl functionalized activated carbon, were considered, and their adsorption energies corresponded to −416.47 kJ/mol, −54.73 kJ/mol, −49.99 kJ/mol, and −63.62 kJ/mol, respectively. The high adsorption energies suggested the chemisorptive nature of the cresol-activated carbon adsorption process. Among the oxygen functional groups, the carboxyl group tended to influence the ...
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
When polymeric materials like Polyallyl diglycol carbonate (PADC), Polycarbonate (PC), Polyvinyl ... more When polymeric materials like Polyallyl diglycol carbonate (PADC), Polycarbonate (PC), Polyvinyl Chloride (PVC), Polypropylene (PP) etc. are exposed to gamma radiation, they show pronounced changes in their physical and chemical properties. Interestingly, the changes due to irradiation are varied in nature, proving that all polymers do not undergo similar type of modifications under similar irradiation conditions. Thus, while polymers like PADC and PVC do not reveal any change in the IR spectral pattern, the IR spectrum of polypropylene polymer confirms the total destruction of isotactic arrangements of the polymer leading to the formation of alcoholic and ketonic groups. The etch-rates are drastically enhanced due to irradiation at the highest dose for all types of PADC detectors which is not the case for polycarbonates. For polyacetate polymer, elimination of carbon dioxide takes place due to destruction of the ester group. Interestingly, in polycarbonate polymer it was observed t...
A new application of nuclear track microfilters has been demonstrated by determining the critical... more A new application of nuclear track microfilters has been demonstrated by determining the critical micelle concentration (CMC) of cationic, anionic and nonionic surfactants. The lowering of CMC due to the addition of methyl red dye in Trition X-100 surfactant (in molar ratio of 1:100) has also been studied. The critical micelle concentrations of cetyl pyridinium chloride (CPC), sodium dodecyl sulphate (SDS) and polyoxyethylene (9.5) octylphenol (Triton X-100) surfactants are determined using polycarbonate nuclear track microfilters and these are found to be comparable with the literature values. The experimental method is described here and the results are discussed.
Investigations are made on the removal of fluoride from water by prepared activated carbons. Thre... more Investigations are made on the removal of fluoride from water by prepared activated carbons. Three activated carbon adsorbents, BKC, BOC and RSC are prepared from selected biomaterials of bergera koenigh, batavia orange and raphanus sativus respectively. The adsorption capacity towards adsorption of fluoride from aqueous solution was studied and was determined by using fixed amount of adsorbent(0.1g/100mL) and a known concentration of adsorbate (5mg/L) solution at 30 minutes agitating time. The data have been analyzed in the light of adsorption isotherms, adsorption kinetic equations and intraparticle diffusion model. Regeneration of adsorbents was studied.
In this work, the synthesis, characterization, and photocatalytic activity of iron-doped titaniu... more In this work, the synthesis, characterization, and photocatalytic activity of iron-doped titanium dioxide nanoparticles (FDT) supported on environmentally benign activated carbon (PAC) has been discussed. The photocatalytic activity of the nanocomposite was investigated for the degradation of Congo red (CR) dye from aqueous solution under visible light (520 nm), and it was observed that 100% degradation for 20 ppm CR solution took place within 60 mins. The experimental data of photodegradation of CR using the FDT/PAC nanocomposite had the highest correlation with Langmuir Hinshelwood model and pseudo-first-order rate kinetics with an apparent rate constant of 0.05341 min 1 and half-life period of 12.97 mins, respectively. The thermodynamics study revealed that the degradation process is exothermic and spontaneous. The effect of interfering ions on the degradation of CR solution was also examined. The photocatalytic antibacterial activity of the nanocomposite was tested against two bacteria pathogens, Escherichia coli and Staphylococcus aureus, and it was found that for the concentration of 10 5 CFU ml 1 , 100% photocatalytic inactivation was achieved for both Escherichia coli in 120 mins and Staphylococcus aureus in 75 mins under visible light irradiation. The total electrical energy consumed and operating cost were measured and the total operating cost was 312.50, 236.74, and 166.67 INR (Indian rupee) for 20 ppm, 60 ppm, and 100 ppm CR dye removal using 0.06 g FDT/PAC nanocomposite, respectively.
Activated carbon was synthesized from Tithonia diversifolia biomass using potassium hydroxide as ... more Activated carbon was synthesized from Tithonia diversifolia biomass using potassium hydroxide as the chemical activating reagent. Taguchi's experimental design approach was applied to determine the best preparation conditions. An optimum 2:1 impregnation ratio and 700°C activation temperature produced the best carbon with a high 854.44 m 2 g-1 surface area, 0.445 cm 3 g-1 total pore volume and 18.3% yield. From the analysis of variance (ANOVA), the impregnation ratio was found to be the most influential factor in preparing activated carbon with the maximum surface area. SEM and XRD studies revealed the porous microcrystallite structure of the obtained activated carbon. Batch adsorption studies were performed to test the efficiency of Tithonia diversifolia activated carbon for the removal of Bisphenol A (BPA) from aqueous solution. A maximum 98.2% removal percentage was attained at optimum conditions of 0.2 g adsorbent dose, pH 7, 80 min contact time and 40 mg L −1 initial BPA concentration. The Langmuir isotherm model described the equilibrium adsorption of BPA well with a maximum adsorption capacity(q m) of 15.69 mg g −1 while the kinetic adsorption study indicated a pseudo second order model. A theoretical investigation suggested that the adsorption of BPA onto the activated carbon mainly proceeds via chemisorption and the presence of a carboxyl functional group on the activated carbon surface yielded a greater adsorptive impact on BPA. This study indicates that Tithonia diversifolia could be used as a potential raw material for preparing activated carbon for removing of BPA from water.
Waterborne pathogens in drinking water affect the lives of millions worldwide especially in the r... more Waterborne pathogens in drinking water affect the lives of millions worldwide especially in the rural areas of developing countries. Access to clean drinking water and modern water purification system is rare in rural community, therefore low maintenance, cost-effective and easy operational point-of-use water purification methods need to be employed to improve the quality of water in rural areas. Thus, the present manuscript gives an idea of the different techniques employed and use of ecofriendly, sustainable and cheap resources for effective removal of pathogens.
Water is a vital resource for sustaining life, however in present scenario the access to clean sa... more Water is a vital resource for sustaining life, however in present scenario the access to clean safe water around the world has become a burning concern especially in developing and emerging countries attributing to increase in population, climate change and environmental water pollution by sewages, industrial effluents, chemicals, domestic wastes, pesticides, pharmaceuticals and so on. These pollutants consist of organic, inorganic, biological and radioactive substances that make the water unfit for any use and poses a threat to human health, animals and plants as they are either toxic, carcinogenic or mutagenic. 1−3 According to report of World Water Development 2017, currently only 20% of wastewater produced globally receives proper treatment while majority of it is discharged without any form of treatment into the environment. 4 The occurrence of organic pollutants in wastewater have increased tremendously in modern years and has become a critical concern because of their toxicity, semi volatile nature, low water solubility, high bioaccumulation and non-biodegradability under normal environmental condition. 5-7 These types of organic pollutants such as phenolic compounds, polycyclic aromatic hydrocarbons (PAHs) and agricultural chemicals (organic pesticides and organic herbicides) have been considered as critical problems as it leads to aquatic system depletion, environmental degradation and also affect human health such as reproductive system disorders, endocrine disruption, obesity and cancer. 8,9 In this regard, water purification have now become the main critical issue worldwide for which strict legislation has been formulated by World Health Organization for organic compounds for Drinking-Water Quality. 10,11 Many ongoing studies in water purification remain a severe challenge to governments, scientists and industries, as lack of cost-effective water purification technology has aggravated the crisis of clean and safe water for the fast expanding population. Over the years, various methodologies to remediate these water threats have been developed, such as photocatalytic degradation, 12 advanced oxidation, 13 micellar enhanced ultra filtration, 14 combined photo-fenton and ultrasound,
The experimental results on the characterization of three polymeric solids in terms of energy-los... more The experimental results on the characterization of three polymeric solids in terms of energy-loss of 20-80 MeV t2C ions m Kapton, Hostaphan and Makrofol-N have been presented and compared with theoretical values.
Activated carbon synthesized from the plant Mucuna prurines have been successfully used to remove... more Activated carbon synthesized from the plant Mucuna prurines have been successfully used to remove fluoride from aqueous solution by adsorption method. Batch method adsorption has been studied and the adsorption was found to be very significant. Almost 96% of fluoride could be removed by adsorption. Adsorption studies of fluoride signify the fact that among the different adsorption model, Langmuir adsorption model seems to be more favorable in the present case. Different parameters like effect of adsorbent dosage, contact time, pH and initial concentration are studied to understand the adsorption mechanism.
Chitosan is known for its absorption and adhesion property and it is a non-toxic biodegradable he... more Chitosan is known for its absorption and adhesion property and it is a non-toxic biodegradable hetero polymer. It has a strong affinity for water and high degree of solubility in acidic medium. In addition, chitosan hydrogels showed low mechanical strength and minimum ability to control the delivery of encapsulated compounds. And hence, in this investigation a set of compounds cross linked with Chitosan was screened for anticancer agent using computational technique (molecular docking) against NOS enzyme (PDB ID: 4NOS). The result was interesting as majority of the compounds screened turned up with favorable molecular interaction and binding affinity as evidenced from the docking score. Furthermore the molecular interaction analysis represents the cross linked compounds possessed heavy molecular interaction at the active site residue of the enzyme. Thus, Chitosan cross linked compounds target the specific active site residue and hence can be used in future for drug delivery.
Gamma irradiation effects on track properties of Polyallyl Diglycol Carbonate (PADC) track detect... more Gamma irradiation effects on track properties of Polyallyl Diglycol Carbonate (PADC) track detector (PADC-American Acrylics) are studied in the dose range of 101-106Gy. It is observed that due to gamma exposure the bulk and track-etch rates of the detector increases. This increase in both etch-rates is more pronounced in post gamma exposed PADC detectors. The etch-rate ratio (S) for both pre and post-gamma exposed detectors decreases with increasing etching temperature at the dose of 106Gy. At a higher etching temperature of 70ºC, the etch rates ratio becomes almost equal for post gamma exposed detector. Etching efficiency of the detector is found to be much higher when exposed to gamma radiation. However it is observed that at the etching temperature of 70ºC, etching efficiency for both pre and post-gamma exposed samples tends to become almost equal to the pristine one.
Microwave-induced solvent-free brominations of organic substrates have been carried out with tetr... more Microwave-induced solvent-free brominations of organic substrates have been carried out with tetrabutylammonioum tribromide,(C4H9) 4N+(Br3–). Reactions are facile, affording products in high yields within very short reaction times. Keywords: Microwave ( ...
... DOI: 10.1080/00397910903531912 Latonglila Jamir a , B. Alimenla a , Anil Kumar a , Dipak Sinh... more ... DOI: 10.1080/00397910903531912 Latonglila Jamir a , B. Alimenla a , Anil Kumar a , Dipak Sinha a ... 2006 , 161 , 687 – 693 ; (l) Alimenla , B. ; Kumar , A. ; Jamir , L. ; Sinha , D. ; Sinha , UB An ... Nath , J. ; Ghosh , H. ; Yella , R. ; Patel , BK Molecular iodine–mediated preparation of ...
E ect of gamma irradiation on thermal properties of di erent types of nuclear track detectors lik... more E ect of gamma irradiation on thermal properties of di erent types of nuclear track detectors like PADC (Homalite), PADC (American-Acrylics), Polycarbonate, Lexan, Makrofol-E, Triafol-TN, Triafol-BN and Polypropylene are studied in the dose range of 10 1-10 6 Gy. For some detectors like PADC (Homalite), Lexan and Makrofol-E, the e ect is not very signiÿcant. But for detectors like PADC (American-Acrylics), the thermal resistance comes down at a dose of 10 6 Gy and the detector decomposes at much lower temperatures. Polycarbonate detectors gain some thermal stability due to gamma exposure at the highest dose. In the case of polypropylene detectors, the thermal stability decreases drastically and the detector decomposes in four di erent steps in comparison to single-step decomposition shown by the pristine one.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2005
Ion irradiation of polymers offers a number of interesting possibilities for applications. In the... more Ion irradiation of polymers offers a number of interesting possibilities for applications. In the case of latent tracks, radiochemical changes, phase transitions, alterations of the intrinsic free volume, or radiation induced defects can be exploited-the latter ones to trap mobile impurities. These approaches are useful to form, e.g. new types of sensors. Apart from this, etched tracks in polymers offer a vast range of possibilities. Practically any material-including colloides and nanocrystals-can be inserted into these pores to form nanowires or nanotubules. Sequential deposition can be made as well in radial as axial direction to form complex nanostructures. Combination with lithography enables one to form different types of novel transistors, microcapacitors,-magnets,-transformers and-sensors. Also sterilizing foils for medicine and packing industry have been made in this way. A number of new ideas are presented how to proceed further in this field.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2000
Ion beam treatment studies have been carried out to investigate the potential for improvements in... more Ion beam treatment studies have been carried out to investigate the potential for improvements in conductivity properties of the polymers Polytetra¯uroethylene (PTFE), Polyimide (PI), Polyethyleneterepthalate (PET) and Polypropylene (PP), after 2 MeV electron and 62 MeV proton irradiation. The shift in optical absorption edges as observed by UV±VIS spectra of the irradiated polymers has been correlated to the optical band-gap using TaucÕs expression. A decrease in the optical band-gap has been observed in irradiated PP and PTFE, but no considerable change was found for the optical band-gaps of PET and PI. Further AC conductivity measurements con®rmed an increase in conductivity in electron irradiated PP.
The efficacies of different organic ammonium tribromides were studied with different classes of o... more The efficacies of different organic ammonium tribromides were studied with different classes of organic substrates using solvent-free reaction protocols involving reactions at elevated temperature and also under microwave conditions. The reactions were regio-selective, facile and afforded good to excellent product yields in short reaction time.
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