Crystalline admixtures(CA),also known as permeability reducer admixtures,are used in binder-based materials to improve concrete durability by reducing water permeability depth,increasing compressive strength,and stimu...Crystalline admixtures(CA),also known as permeability reducer admixtures,are used in binder-based materials to improve concrete durability by reducing water permeability depth,increasing compressive strength,and stimulating crack healing.The purpose of this study is to evaluate the potential of crystalline admixtures to enhance the self-healing characteristics and durability attributes of concrete and to contribute to the understanding of their role in the design of long-term efficiency and sustainability.The 28 days specimens of M40 grade concrete were prepared by adding CA and cast as 150 mm cubes,25×25×285 mm prisms and disks with a diameter of 100 mm and height of 50 mm.All samples were then tested for compressive strength,water permeability,dry shrinkage,sodium sulfate attack test,Rapid Chloride Migration Test(RCMT),and rapid chloride penetration test(RCPT)to study the behavior of incorporating crystalline admixtures in concrete.The conclusion drawn from this study was that the addition of a crystalline admixture of 0.8%resulted in an increase in the compressive strength by 7.98%and a decrease in water penetration depth through the cube by 71.5%,while the dry shrinkage of the specimen incorporated with the crystalline admixture was 65.21%less than that of the specimen without the crystalline admixture.These results substantiate the beneficial role of CA in increasing the durability of concrete through increased strength,lower permeability,and better dimensional stability,thus making crystalline admixtures beneficial for incorporation into high-performance concrete applications.展开更多
The review investigates the use of biomass-derived carbon as precursors for nanomaterials,acknowledging their sustainability and eco-friendliness.It examines various types of biomasses,such as agricultural residues an...The review investigates the use of biomass-derived carbon as precursors for nanomaterials,acknowledging their sustainability and eco-friendliness.It examines various types of biomasses,such as agricultural residues and food byproducts,focussing on their transformation via environmentally friendly methods such as pyrolysis and hydrothermal carbonisation.Innovations in creating porous carbon nanostructures and heteroatom surface functionalisation are identified,enhancing catalytic performance.The study also explores the integration of biomassderived carbon with nanomaterials for energy storage,catalysis,and other applications,noting the economic and environmental benefits.Despite these advantages,challenges persist in optimising synthesis methods and scaling production.The study also highlights existing research gaps,forms a basis for future studies,and underscores the role of biomass-derived nanomaterials in promoting a circular economy and sustainability.展开更多
Background:Cannabidiol(CBD)has numerous therapeutic properties,and is used to treat neurological conditions,such as neuroinflammation.However,the optimal dose of CBD to penetrate the brain requires further investigati...Background:Cannabidiol(CBD)has numerous therapeutic properties,and is used to treat neurological conditions,such as neuroinflammation.However,the optimal dose of CBD to penetrate the brain requires further investigation.The primary aim of this study was to use a mouse model and the intrabuccal route for CBD administration to determine the optimal dose at which CBD can penetrate the brain.The secondary aim was to determine whether sex is a confounding factor.Methods:Thirty adult Kramnik mice,divided equally into three groups,were ad-ministered CBD oil intrabuccally at three doses-10,20,and 30 mg/kg,euthanized 6 h later,and whole brain,urine,and blood samples were collected.Liquid chro-matography with tandem mass spectrometry was used to analyze the collected samples.Results:CBD and its three metabolites—7-carboxy cannabidiol(7-COOH-CBD),7-hydroxy cannabidiol(7-OH-CBD)and 6-hydroxy cannabidiol(6-OH-CBD),were identified and quantified in all samples.The 10 and 20 mg/kg doses of CBD produced similar results in the brain,but the group given the 10 mg/kg dose had the least vari-ation.The 30 mg/kg dose yielded the highest abundance of CBD and its metabolites in all samples,but also the greatest variation.Sex only became a confounding factor at 30 mg/kg.Conclusions:This study shows that the intrabuccal route of CBD administration is reliable and the 10 mg/kg dose of CBD is recommended in mice because there were good CBD metabolite concentrations in all samples,with the least variation among the doses,and sex was not a confounder at 10 mg/kg.展开更多
In this research work, atomic and molecular orbitals based analysis has been made to see electronic structure of platinum halides (platinum dichloride, platinum dibromide, platinum diiodide and platinum difluride). Th...In this research work, atomic and molecular orbitals based analysis has been made to see electronic structure of platinum halides (platinum dichloride, platinum dibromide, platinum diiodide and platinum difluride). The geometry optimization and three dimensional (3D) modeling of the above mentioned species have been made on CAChe pro software. The results show: (i) The involvement of three p atomic orbitals is negligible as their summation values are very low in comparison to d orbital and considerably low with respect to s orbital. (ii) The study well support the Landis concepts of sdn-hybridation (here n = 1) as bond angle and contributions of s-orbital and d-orbital of Pt(II) are maximum with negligible contribution of p-orbitals. (iii) These halides also support the cloud-expanding effect with experimental data and also follow the nephelauxetic effect. The result is in good agreement with experiment results that covalent character increases in the order: PtI2 > PtBr2 > PtCl2 > PtF2. (iv) And thus the study will help to fine tune the existing complexes of these halides.展开更多
Fiber reinforcement significantly enhances the strength,toughness,and durability of concrete by reducing the propagation of microcracks in the concrete matrix.With the rising demand for high-performance concrete(HPC),...Fiber reinforcement significantly enhances the strength,toughness,and durability of concrete by reducing the propagation of microcracks in the concrete matrix.With the rising demand for high-performance concrete(HPC),this study investigates the mechanical properties of HPC with varying proportions of polypropylene(PP)and steel(ST)fibers.Supplementary cementitious materials(SCMs)toward partial replacement of ordinary Portland cement(OPC)were incorporated to prepare HPC mixes as a ternary composite system using Fly Ash(FA),Silica Fume(SF),and Ground Granulated Blast Furnace Slag(GGBS).Each HPC mix comprised two SCMs,accounting for 20%of the mass fraction of the OPC binder.The study encompassed fiber percentages ranging from 0 to 0.075%PP and 0 to 2%ST,incorporating them into the HPC mixes with gradual increases of 0.025%for PP and 0.5%for ST fiber by mass fraction.All HPC mixes were tested for mechanical properties using compressive and split tensile strength tests.The influence of SCMs on HPC was studied using X-ray diffraction(XRD)for microstructural analyses.It was found that the compressive and split tensile strengths of HPC increased up to an optimal fiber percentage and then decreased.A comparison of the test results of high-performance fiber-reinforced concrete with those of plain HPC revealed significant improvements in compressive and splitting tensile strengths by 26.59%and 57.74%,respectively.Also,the XRD analysis revealed that the composition of the SCMs in HPC was a significant and effective solution for the mechanical properties of the concrete.展开更多
Background:Acute Myeloid Leukemia(AML)is a highly aggressive clonal hematological malignancy with limited treatment options.This study aimed to evaluate the therapeutic potential of nigericin,a polyether ionophore der...Background:Acute Myeloid Leukemia(AML)is a highly aggressive clonal hematological malignancy with limited treatment options.This study aimed to evaluate the therapeutic potential of nigericin,a polyether ionophore derived from Streptomyces DASNCL-29,as a mitochondrial-targeted agent for AML treatment.Methods:Nigericin was isolated from Streptomyces DASNCL-29 and characterized via chromatography and NMR.Its cytotoxicity was tested in MOLM13(sensitive and venetoclax-resistant)and HL60(sensitive and cytarabine-resistant)cells using the MTT assay.Mitochondrial dysfunction was assessed by measuring reactive oxygen species(ROS),mitochondrial membrane potential(Δψm),and mitochondrial mass.Apoptosis was evaluated with Annexin V/PI assays and immunoblotting,while proteomic analysis was conducted using Liquid Chromatography-Tandem Mass Spectrometry(LC-MS/MS)to identify differentially regulated proteins.Results:Nigericin demonstrated potent cytotoxicity with IC50 values of 57.02 nM in MOLM13-sensitive,35.29 nM in MOLM13-resistant,20.49 nM in HL60-sensitive,and 1.197 nM in HL60-cytarabine-resistant cells.Apoptosis was confirmed by Annexin V/PI staining and caspase-3/PARP cleavage,along with MCL-1 downregulation.Mitochondrial dysfunction was evident from increased ROS,reducedΔψm,and decreased mitochondrial mass.Proteomic profiling identified 264 dysregulated proteins,including a 3.8-fold upregulation of Succinate Dehydrogenase[Ubiquinone]Flavoprotein Subunit A(SDHA).Conclusion:Nigericin induces apoptosis in AML cells by disrupting mitochondrial function and enhancing oxidative stress.Its nanomolar potency highlights the need for further mechanistic studies and in vivo evaluations to explore its potential in AML treatment.展开更多
The materialization of polybutylene succinate(PBS)belongs to the family of polyesters which are degrad-able and biodegradable,their biodegradability properties have attracted enormous interest for product development ...The materialization of polybutylene succinate(PBS)belongs to the family of polyesters which are degrad-able and biodegradable,their biodegradability properties have attracted enormous interest for product development towards different polymer-based applications.Besides its biodegradability,PBS can be derived from petroleum and biobased monomers.At the same time,the latter is the driving factor for its growing interest in bioplastics for fully green and sustainable biobased-derived polymer products.The processes and techniques presented herein,are based on the production of biobased succinic acid monomer to PBS.However,the counterpart biobased monomer 1,4-butanediol(1,4-BDO)production has not been commercially demonstrated.This review discusses the progress in state-of-the-art developments in the synthesis strategies of PBS,its copolymers,and composites with the view to improve molecular weight,thermal,and mechanical properties.It further analyzes the different strategies to synthesize modified PBS polymer composites from organic and inorganic nanofillers to enhance their chemical,thermal,stability and mechanical structural properties.Importantly,the review highlights the progress in the applications of PBS copolymers and composites with tailored structure-designed properties for specific sectors such as packaging films,biomedical and drug release,fire retardants,and agricultural products.The structure-functional performance characteristics of these developments in the PBS,copolymers,and composites are highlighted to provide baseline insights for future developments in engineering the specific applications,and structural interface PBS composites with enhanced structure-functional performance properties.展开更多
The problem of textile dye pollution has been addressed by various methods,mainly physical,chemical,biological,and acoustical.These methods mainly separate and/or remove the dye present in water.Recently,advanced oxid...The problem of textile dye pollution has been addressed by various methods,mainly physical,chemical,biological,and acoustical.These methods mainly separate and/or remove the dye present in water.Recently,advanced oxidation processes（AOP）have been focused for removal of dye from waste water due to their advantages such as ecofriendly,economic and capable to degrade many dyes or organic pollutant present in water.Photocatalysis is one of the advance oxidation processes,mainly carried out under irradiation of light and suitable photocatalytic materials.The photocatalytic activity of the photocatalytic materials mainly depends on the band gap,surface area,and generation of electron–hole pair for degradation dyes present in water.It has been observed that the surface area plays a major role in photocatalytic degradation of dyes,by providing higher surface area,which leads to the higher adsorption of dye molecule on the surface of photocatalyst and enhances the photocatalytic activity.This present review discusses the synergic effect of adsorption of dyes on the photocatalytic efficiency of various nanostructured high surface area photocatalysts.In addition,it also provides the properties of the water polluting dyes,their mechanism and various photocatalytic materials;and their morphology used for the dye degradation under irradiation of light along with the future prospects of highly adsorptive photocatalytic material and their application in photocatalytic removal of dye from waste water.展开更多
The slurry settling characteristics are the most important to design a thickener in process industries. In this work, the iron ore slurry from the screw classifier overflow was used for the settling study. It was obse...The slurry settling characteristics are the most important to design a thickener in process industries. In this work, the iron ore slurry from the screw classifier overflow was used for the settling study. It was observed that the original slurry exhibited a low settling velocity and a turbid supernatant during the settling process. Commercial flocculating agents with anionic, cationic, and nonionic characters were used to improve the settling behavior of suspensions, which were added into the slurry at different ranges of slurry pH values, respectively. The settling results show that the use of flocculants increase the settling rate by several times. Compared with the cationic and non-ionic flocculants, the anionic flocculant is more effective in enhancing the slurry settling rate. The small dose of the anionic flocculant is found to be more effective, but the other flocculants are less effective even at higher dosages. The simulation of an industrial thickener was carried out based on the laboratory settling data, and the appropriate design and selection parameters of the industrial thickener were estimated.展开更多
Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesi...Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesis of n-butyl levulinate by esterification of levulinic acid with n-butanol using heteropolyacid （HPA） supported on acid-treated clay montmorillonite （K10）. 20% （w/w） dodecatungestophosphoric acid （DTPA） supported on K10 was found to be the most efficient catalyst with 97% levulinic acid conversion and 100% selectivity towards n-butyl levulinate. Effects of various process parameters were studied to examine the efficacy of 20% （w/w） DTPA/K10 for optimization of the activity.展开更多
Beneficiation of non-coking coal is gaining ground in India. It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses. For special applications...Beneficiation of non-coking coal is gaining ground in India. It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses. For special applications such as the fuel for integrated gasification combined cycle plant （IGCC）, the ash content in the coal should preferably be below 15 %. Indian coals are characterized by high inter-grown ash content mainly due to ＇drift origin＇ of Gondwana formation in Permian age. This warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals. A non- coking coal sample of vitrinite type from India was ground to 44 ~tm （dso） and subjected to column flotation to improve its quality. The non-coking coal analyzing 34.6 % ash, 26.2 % volatile matter, 1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters, namely, froth depth, superficial feed velocity and superficial air velocity. The concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route.展开更多
The effects of a fine water mist environment in a semi-confined blast chamber on the chemical and thermodynamic processes following detonation of a 20 g PE4 explosive charge have been investigated.The effects were qua...The effects of a fine water mist environment in a semi-confined blast chamber on the chemical and thermodynamic processes following detonation of a 20 g PE4 explosive charge have been investigated.The effects were quantified by the analysis of pressure profiles recorded where several parameters including arrival time of the shock at the sensors, peak overpressures, specific impulse of the positive phase, period of the negative phase and the specific impulse of the multiple reflections were quantified.The effect of the fine water mist on the arrival time, peak pressures and the specific impulse of the positive phase agrees with previous findings in literature. In this paper, the focus is on the implications of the fine water mist on the negative phase and the impulse of multiple pressure reflections. The period of the negative phase was found to have increased by 40% and with higher negative peak pressure in the mist condition compared to the atmospheric condition. The activities of the multiple pressure reflections were found to have decreased considerably, both in number and in amplitude leading to lower impulses(by about 60%) for the water mist conditions.展开更多
文摘Crystalline admixtures(CA),also known as permeability reducer admixtures,are used in binder-based materials to improve concrete durability by reducing water permeability depth,increasing compressive strength,and stimulating crack healing.The purpose of this study is to evaluate the potential of crystalline admixtures to enhance the self-healing characteristics and durability attributes of concrete and to contribute to the understanding of their role in the design of long-term efficiency and sustainability.The 28 days specimens of M40 grade concrete were prepared by adding CA and cast as 150 mm cubes,25×25×285 mm prisms and disks with a diameter of 100 mm and height of 50 mm.All samples were then tested for compressive strength,water permeability,dry shrinkage,sodium sulfate attack test,Rapid Chloride Migration Test(RCMT),and rapid chloride penetration test(RCPT)to study the behavior of incorporating crystalline admixtures in concrete.The conclusion drawn from this study was that the addition of a crystalline admixture of 0.8%resulted in an increase in the compressive strength by 7.98%and a decrease in water penetration depth through the cube by 71.5%,while the dry shrinkage of the specimen incorporated with the crystalline admixture was 65.21%less than that of the specimen without the crystalline admixture.These results substantiate the beneficial role of CA in increasing the durability of concrete through increased strength,lower permeability,and better dimensional stability,thus making crystalline admixtures beneficial for incorporation into high-performance concrete applications.
基金financial assistance of the National Research Foundation(NRF),grant number(138079)Eskom,grant number(2002/015527/0)South Africa,towards this research is acknowledged.
文摘The review investigates the use of biomass-derived carbon as precursors for nanomaterials,acknowledging their sustainability and eco-friendliness.It examines various types of biomasses,such as agricultural residues and food byproducts,focussing on their transformation via environmentally friendly methods such as pyrolysis and hydrothermal carbonisation.Innovations in creating porous carbon nanostructures and heteroatom surface functionalisation are identified,enhancing catalytic performance.The study also explores the integration of biomassderived carbon with nanomaterials for energy storage,catalysis,and other applications,noting the economic and environmental benefits.Despite these advantages,challenges persist in optimising synthesis methods and scaling production.The study also highlights existing research gaps,forms a basis for future studies,and underscores the role of biomass-derived nanomaterials in promoting a circular economy and sustainability.
基金National Research Fund of South Africa(grant number:137792).
文摘Background:Cannabidiol(CBD)has numerous therapeutic properties,and is used to treat neurological conditions,such as neuroinflammation.However,the optimal dose of CBD to penetrate the brain requires further investigation.The primary aim of this study was to use a mouse model and the intrabuccal route for CBD administration to determine the optimal dose at which CBD can penetrate the brain.The secondary aim was to determine whether sex is a confounding factor.Methods:Thirty adult Kramnik mice,divided equally into three groups,were ad-ministered CBD oil intrabuccally at three doses-10,20,and 30 mg/kg,euthanized 6 h later,and whole brain,urine,and blood samples were collected.Liquid chro-matography with tandem mass spectrometry was used to analyze the collected samples.Results:CBD and its three metabolites—7-carboxy cannabidiol(7-COOH-CBD),7-hydroxy cannabidiol(7-OH-CBD)and 6-hydroxy cannabidiol(6-OH-CBD),were identified and quantified in all samples.The 10 and 20 mg/kg doses of CBD produced similar results in the brain,but the group given the 10 mg/kg dose had the least vari-ation.The 30 mg/kg dose yielded the highest abundance of CBD and its metabolites in all samples,but also the greatest variation.Sex only became a confounding factor at 30 mg/kg.Conclusions:This study shows that the intrabuccal route of CBD administration is reliable and the 10 mg/kg dose of CBD is recommended in mice because there were good CBD metabolite concentrations in all samples,with the least variation among the doses,and sex was not a confounder at 10 mg/kg.
文摘In this research work, atomic and molecular orbitals based analysis has been made to see electronic structure of platinum halides (platinum dichloride, platinum dibromide, platinum diiodide and platinum difluride). The geometry optimization and three dimensional (3D) modeling of the above mentioned species have been made on CAChe pro software. The results show: (i) The involvement of three p atomic orbitals is negligible as their summation values are very low in comparison to d orbital and considerably low with respect to s orbital. (ii) The study well support the Landis concepts of sdn-hybridation (here n = 1) as bond angle and contributions of s-orbital and d-orbital of Pt(II) are maximum with negligible contribution of p-orbitals. (iii) These halides also support the cloud-expanding effect with experimental data and also follow the nephelauxetic effect. The result is in good agreement with experiment results that covalent character increases in the order: PtI2 > PtBr2 > PtCl2 > PtF2. (iv) And thus the study will help to fine tune the existing complexes of these halides.
基金financed by the Science and Engineering Research Board,India,in Project No.EEQ/2023/000130CSIR-India in Project No.MLP072002.
文摘Fiber reinforcement significantly enhances the strength,toughness,and durability of concrete by reducing the propagation of microcracks in the concrete matrix.With the rising demand for high-performance concrete(HPC),this study investigates the mechanical properties of HPC with varying proportions of polypropylene(PP)and steel(ST)fibers.Supplementary cementitious materials(SCMs)toward partial replacement of ordinary Portland cement(OPC)were incorporated to prepare HPC mixes as a ternary composite system using Fly Ash(FA),Silica Fume(SF),and Ground Granulated Blast Furnace Slag(GGBS).Each HPC mix comprised two SCMs,accounting for 20%of the mass fraction of the OPC binder.The study encompassed fiber percentages ranging from 0 to 0.075%PP and 0 to 2%ST,incorporating them into the HPC mixes with gradual increases of 0.025%for PP and 0.5%for ST fiber by mass fraction.All HPC mixes were tested for mechanical properties using compressive and split tensile strength tests.The influence of SCMs on HPC was studied using X-ray diffraction(XRD)for microstructural analyses.It was found that the compressive and split tensile strengths of HPC increased up to an optimal fiber percentage and then decreased.A comparison of the test results of high-performance fiber-reinforced concrete with those of plain HPC revealed significant improvements in compressive and splitting tensile strengths by 26.59%and 57.74%,respectively.Also,the XRD analysis revealed that the composition of the SCMs in HPC was a significant and effective solution for the mechanical properties of the concrete.
文摘Background:Acute Myeloid Leukemia(AML)is a highly aggressive clonal hematological malignancy with limited treatment options.This study aimed to evaluate the therapeutic potential of nigericin,a polyether ionophore derived from Streptomyces DASNCL-29,as a mitochondrial-targeted agent for AML treatment.Methods:Nigericin was isolated from Streptomyces DASNCL-29 and characterized via chromatography and NMR.Its cytotoxicity was tested in MOLM13(sensitive and venetoclax-resistant)and HL60(sensitive and cytarabine-resistant)cells using the MTT assay.Mitochondrial dysfunction was assessed by measuring reactive oxygen species(ROS),mitochondrial membrane potential(Δψm),and mitochondrial mass.Apoptosis was evaluated with Annexin V/PI assays and immunoblotting,while proteomic analysis was conducted using Liquid Chromatography-Tandem Mass Spectrometry(LC-MS/MS)to identify differentially regulated proteins.Results:Nigericin demonstrated potent cytotoxicity with IC50 values of 57.02 nM in MOLM13-sensitive,35.29 nM in MOLM13-resistant,20.49 nM in HL60-sensitive,and 1.197 nM in HL60-cytarabine-resistant cells.Apoptosis was confirmed by Annexin V/PI staining and caspase-3/PARP cleavage,along with MCL-1 downregulation.Mitochondrial dysfunction was evident from increased ROS,reducedΔψm,and decreased mitochondrial mass.Proteomic profiling identified 264 dysregulated proteins,including a 3.8-fold upregulation of Succinate Dehydrogenase[Ubiquinone]Flavoprotein Subunit A(SDHA).Conclusion:Nigericin induces apoptosis in AML cells by disrupting mitochondrial function and enhancing oxidative stress.Its nanomolar potency highlights the need for further mechanistic studies and in vivo evaluations to explore its potential in AML treatment.
文摘The materialization of polybutylene succinate(PBS)belongs to the family of polyesters which are degrad-able and biodegradable,their biodegradability properties have attracted enormous interest for product development towards different polymer-based applications.Besides its biodegradability,PBS can be derived from petroleum and biobased monomers.At the same time,the latter is the driving factor for its growing interest in bioplastics for fully green and sustainable biobased-derived polymer products.The processes and techniques presented herein,are based on the production of biobased succinic acid monomer to PBS.However,the counterpart biobased monomer 1,4-butanediol(1,4-BDO)production has not been commercially demonstrated.This review discusses the progress in state-of-the-art developments in the synthesis strategies of PBS,its copolymers,and composites with the view to improve molecular weight,thermal,and mechanical properties.It further analyzes the different strategies to synthesize modified PBS polymer composites from organic and inorganic nanofillers to enhance their chemical,thermal,stability and mechanical structural properties.Importantly,the review highlights the progress in the applications of PBS copolymers and composites with tailored structure-designed properties for specific sectors such as packaging films,biomedical and drug release,fire retardants,and agricultural products.The structure-functional performance characteristics of these developments in the PBS,copolymers,and composites are highlighted to provide baseline insights for future developments in engineering the specific applications,and structural interface PBS composites with enhanced structure-functional performance properties.
基金CSIR-CSMCRI communication No.160/2016funding through Network Project on "Waste to Wealth-Waste Plastics (W2W)" (Project No: CSC-0120)
文摘The problem of textile dye pollution has been addressed by various methods,mainly physical,chemical,biological,and acoustical.These methods mainly separate and/or remove the dye present in water.Recently,advanced oxidation processes（AOP）have been focused for removal of dye from waste water due to their advantages such as ecofriendly,economic and capable to degrade many dyes or organic pollutant present in water.Photocatalysis is one of the advance oxidation processes,mainly carried out under irradiation of light and suitable photocatalytic materials.The photocatalytic activity of the photocatalytic materials mainly depends on the band gap,surface area,and generation of electron–hole pair for degradation dyes present in water.It has been observed that the surface area plays a major role in photocatalytic degradation of dyes,by providing higher surface area,which leads to the higher adsorption of dye molecule on the surface of photocatalyst and enhances the photocatalytic activity.This present review discusses the synergic effect of adsorption of dyes on the photocatalytic efficiency of various nanostructured high surface area photocatalysts.In addition,it also provides the properties of the water polluting dyes,their mechanism and various photocatalytic materials;and their morphology used for the dye degradation under irradiation of light along with the future prospects of highly adsorptive photocatalytic material and their application in photocatalytic removal of dye from waste water.
文摘The slurry settling characteristics are the most important to design a thickener in process industries. In this work, the iron ore slurry from the screw classifier overflow was used for the settling study. It was observed that the original slurry exhibited a low settling velocity and a turbid supernatant during the settling process. Commercial flocculating agents with anionic, cationic, and nonionic characters were used to improve the settling behavior of suspensions, which were added into the slurry at different ranges of slurry pH values, respectively. The settling results show that the use of flocculants increase the settling rate by several times. Compared with the cationic and non-ionic flocculants, the anionic flocculant is more effective in enhancing the slurry settling rate. The small dose of the anionic flocculant is found to be more effective, but the other flocculants are less effective even at higher dosages. The simulation of an industrial thickener was carried out based on the laboratory settling data, and the appropriate design and selection parameters of the industrial thickener were estimated.
基金S. Dharne thanks Director, NCL, Pune for permission to workas an M. E. (Chemical Engineering) project trainee
文摘Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesis of n-butyl levulinate by esterification of levulinic acid with n-butanol using heteropolyacid （HPA） supported on acid-treated clay montmorillonite （K10）. 20% （w/w） dodecatungestophosphoric acid （DTPA） supported on K10 was found to be the most efficient catalyst with 97% levulinic acid conversion and 100% selectivity towards n-butyl levulinate. Effects of various process parameters were studied to examine the efficacy of 20% （w/w） DTPA/K10 for optimization of the activity.
文摘Beneficiation of non-coking coal is gaining ground in India. It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses. For special applications such as the fuel for integrated gasification combined cycle plant （IGCC）, the ash content in the coal should preferably be below 15 %. Indian coals are characterized by high inter-grown ash content mainly due to ＇drift origin＇ of Gondwana formation in Permian age. This warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals. A non- coking coal sample of vitrinite type from India was ground to 44 ~tm （dso） and subjected to column flotation to improve its quality. The non-coking coal analyzing 34.6 % ash, 26.2 % volatile matter, 1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters, namely, froth depth, superficial feed velocity and superficial air velocity. The concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route.
文摘The effects of a fine water mist environment in a semi-confined blast chamber on the chemical and thermodynamic processes following detonation of a 20 g PE4 explosive charge have been investigated.The effects were quantified by the analysis of pressure profiles recorded where several parameters including arrival time of the shock at the sensors, peak overpressures, specific impulse of the positive phase, period of the negative phase and the specific impulse of the multiple reflections were quantified.The effect of the fine water mist on the arrival time, peak pressures and the specific impulse of the positive phase agrees with previous findings in literature. In this paper, the focus is on the implications of the fine water mist on the negative phase and the impulse of multiple pressure reflections. The period of the negative phase was found to have increased by 40% and with higher negative peak pressure in the mist condition compared to the atmospheric condition. The activities of the multiple pressure reflections were found to have decreased considerably, both in number and in amplitude leading to lower impulses(by about 60%) for the water mist conditions.
