Nickel and nickel-ceria catalysts supported on high surface area silica, with 6 wt% Ni and 20 wt% CeO2 were prepared by microwave assisted(co) precipitation method. The catalysts were investigated by XRD,TPR and XPS a...Nickel and nickel-ceria catalysts supported on high surface area silica, with 6 wt% Ni and 20 wt% CeO2 were prepared by microwave assisted(co) precipitation method. The catalysts were investigated by XRD,TPR and XPS analyses and they were tested in partial oxidation of methane(CPO). The catalytic reaction was carried out at atmospheric pressure in a temperature range of 400–800℃ with a feed gas mixture containing methane and oxygen in a molecular ratio CH4/O2=2. The Ni catalyst exhibited 60% methane conversion with 60% selectivity to CO already at 500℃. On the contrary, the Ni–Ce catalyst was inert to CPO up to 700℃. Moreover, the former catalyst reproduced its activity at the descending temperatures maintaining a good stability at 600℃, over a reaction time of 80 h, whereas the latter one completely deactivated. Test of CH4 temperature programmed surface reaction(CH4-TPSR) revealed a higher methane activation temperature(> 100℃) for the Ni–Ce catalyst as compared to the Ni one. Noticeable improvement of the ceria containing catalyst occurred when the reaction test started at a temperature higher than the methane decomposition temperature. In this case, the sample achieved the same catalytic behavior of the Ni catalyst. As confirmed by XPS analyses, the distinct electronic state of the supported nickel was responsible for the differences in catalytic behavior.展开更多
The hole-hole interaction(Ehh) has been considered in a CdTe/Cd1-x Mnx Te Semimagnetic Quantum Well Wire(SQWW). The influence of the shape of the confining potential like square well and parabolic well type on the bin...The hole-hole interaction(Ehh) has been considered in a CdTe/Cd1-x Mnx Te Semimagnetic Quantum Well Wire(SQWW). The influence of the shape of the confining potential like square well and parabolic well type on the binding energy of an acceptor impurity with two holes and their Coulomb interaction between them has been studied for various impurity locations. Magnetic field has been used as a probe to understand the carrier-carrier correlation in such Quasi 1-Dimensional QWW since it alters the strength of the confining potential tremendously. In order to show the significance of the correlation between the two holes, the calculations have been done with and without including the correlation effect in the ground state wavefunction of the hyderogenic acceptor impurity and the results have been compared. The expectation value of the Hamiltonian, H, is minimized variationaly in the effective mass approximation through which(Ehh) has been obtained.展开更多
NaP zeolite particles were prepared through a template-free hydrothermal condition at 100oC. Parameters like Na2O/Si O2 and Si O2/Al2O3 molar ratios, gel aging time and aging temperature were investigated for regulati...NaP zeolite particles were prepared through a template-free hydrothermal condition at 100oC. Parameters like Na2O/Si O2 and Si O2/Al2O3 molar ratios, gel aging time and aging temperature were investigated for regulating the crystallization of the final product. The samples at different synthesis stages were characterized with N2 adsorption at-196oC, field emission scanning electron microscopy(FE-SEM), temperature programmed desorption of ammonia adsorption, X-ray diffraction, thermogravimetric and differential scanning calorimetry analysis and Fourier transform infrared spectroscopy. The experimental results evidenced that a high ordering crystallinity of Na P zeolite was obtained at Na2O/Si O2 and Si O2/Al2O3 molar ratios of 1.10 and 1.40, respectively, and a temperature of 100°C for 4 days of aging. FE-SEM image exhibited polycrystalline aggregates of Na P zeolite with crystallite sizes ranging up to 5.04 μm with cactus/cabbage like structures. The quantitative analysis of the total number of acid sites was found to increase as Na2 O increases. The Na P zeolite sample with a Na2O/Si O2 molar ratio of 1.13 exhibited a large fraction of the acid sites on its external surface, contrary to that synthesized with a relevant ratio of 1.10. The optimized Na P zeolite could be successfully bestowed with excellent sorption properties of Ca(II) in aqueous solution. The kinetic parameters for Ca(II) adsorption were thoroughly investigated.展开更多
Microbial electrolysis cell(MEC)is a potential technology to meet the increasing interest in finding new sources of energy that will not harm the environment.MEC is an alternative energy conversion technology for the ...Microbial electrolysis cell(MEC)is a potential technology to meet the increasing interest in finding new sources of energy that will not harm the environment.MEC is an alternative energy conversion technology for the production of biofuels.It is possible to produce hydrogen by fermenting biogenous wastes with hydrogen-producing bacteria.This study investigated the biohydrogen production from co-substrates using electrogenic bacteria such as Escherichia coli,Salmonella bongori,and Shewanella oneidensis in pure culture and as a co-culture,which has the potential to be used as co-substrate in MECs.Briefly,150 mL working-volume reactors were constructed for batch biohydrogen production.The hydrogen production rate(HPR)from the co-substrate was maximum at a ratio of 75:25 g/L with a co-culture of 2.35 mL/(L h).Fabricated a single-chamber membrane-free microelectrolysis cell to evaluate the power density,current density,voltage,HPR,chemical oxygen demand(COD)removal efficiency and Columbic efficiency.Scanning electron microscope(SEM)imaging confirmed the binding of electrogenic bacteria to anode and cathode.The efficiency of electrical conductivity of MEC was analyzed by three different electrodes,namely,nickel,copper and aluminum.The HPR was high using nickel when compared to the other two electrodes.The HPR of a single chamber using a nickel electrode was 2.8 HPR ml/L H_(2) d^(−1) and provided a power density of 17.7 mW/m^(2) at pH 7.This study suggests that the nickel cathode in a single chamber could be a promising sustainable source for stable power generation.展开更多
Nowadays,a number of promising strategies are being developed that aim at combining diagnostic and therapeutic capabilities into clinically effective formulations.Thus,the combination of a modified release provided by...Nowadays,a number of promising strategies are being developed that aim at combining diagnostic and therapeutic capabilities into clinically effective formulations.Thus,the combination of a modified release provided by an organic encapsulation and the intrinsic physico-chemical properties from an inorganic counterpart opens new perspectives in biomedical applications.Herein,a biocompatible magnetic lipid nanocomposite vehicle was developed through an efficient,green and simple method to simultaneously incorporate magnetic nanoparticles and an anticancer drug(doxorubicin)into a natural nano-matrix.The theranostic performance of the final magnetic formulation was validated in vitro and in vivo,in melanoma tumors.The systemic administration of the proposed magnetic hybrid nanocomposite carrier enhanced anti-tumoral activity through a synergistic combination of magnetic hyperthermia effects and antimitotic therapy,together with MRI reporting capability.The application of an alternating magnetic field was found to play a dual role,(i)acting as an extra layer of control(remote,on-demand)over the chemotherapy release and(ii)inducing a local thermal ablation of tumor cells.This combination of chemotherapy with thermotherapy establishes a synergistic platform for the treatment of solid malignant tumors under lower drug dosing schemes,which may realize the dual goal of reduced systemic toxicity and enhanced anti-tumoral efficacy.展开更多
基金The Executive Programme for Cooperation between Italy and India (Prot.No.MAE01054762017)。
文摘Nickel and nickel-ceria catalysts supported on high surface area silica, with 6 wt% Ni and 20 wt% CeO2 were prepared by microwave assisted(co) precipitation method. The catalysts were investigated by XRD,TPR and XPS analyses and they were tested in partial oxidation of methane(CPO). The catalytic reaction was carried out at atmospheric pressure in a temperature range of 400–800℃ with a feed gas mixture containing methane and oxygen in a molecular ratio CH4/O2=2. The Ni catalyst exhibited 60% methane conversion with 60% selectivity to CO already at 500℃. On the contrary, the Ni–Ce catalyst was inert to CPO up to 700℃. Moreover, the former catalyst reproduced its activity at the descending temperatures maintaining a good stability at 600℃, over a reaction time of 80 h, whereas the latter one completely deactivated. Test of CH4 temperature programmed surface reaction(CH4-TPSR) revealed a higher methane activation temperature(> 100℃) for the Ni–Ce catalyst as compared to the Ni one. Noticeable improvement of the ceria containing catalyst occurred when the reaction test started at a temperature higher than the methane decomposition temperature. In this case, the sample achieved the same catalytic behavior of the Ni catalyst. As confirmed by XPS analyses, the distinct electronic state of the supported nickel was responsible for the differences in catalytic behavior.
基金Supported by University Grants Commission,New Delhi,India under Major Research Project F.No.42-816/2013(SR)
文摘The hole-hole interaction(Ehh) has been considered in a CdTe/Cd1-x Mnx Te Semimagnetic Quantum Well Wire(SQWW). The influence of the shape of the confining potential like square well and parabolic well type on the binding energy of an acceptor impurity with two holes and their Coulomb interaction between them has been studied for various impurity locations. Magnetic field has been used as a probe to understand the carrier-carrier correlation in such Quasi 1-Dimensional QWW since it alters the strength of the confining potential tremendously. In order to show the significance of the correlation between the two holes, the calculations have been done with and without including the correlation effect in the ground state wavefunction of the hyderogenic acceptor impurity and the results have been compared. The expectation value of the Hamiltonian, H, is minimized variationaly in the effective mass approximation through which(Ehh) has been obtained.
文摘NaP zeolite particles were prepared through a template-free hydrothermal condition at 100oC. Parameters like Na2O/Si O2 and Si O2/Al2O3 molar ratios, gel aging time and aging temperature were investigated for regulating the crystallization of the final product. The samples at different synthesis stages were characterized with N2 adsorption at-196oC, field emission scanning electron microscopy(FE-SEM), temperature programmed desorption of ammonia adsorption, X-ray diffraction, thermogravimetric and differential scanning calorimetry analysis and Fourier transform infrared spectroscopy. The experimental results evidenced that a high ordering crystallinity of Na P zeolite was obtained at Na2O/Si O2 and Si O2/Al2O3 molar ratios of 1.10 and 1.40, respectively, and a temperature of 100°C for 4 days of aging. FE-SEM image exhibited polycrystalline aggregates of Na P zeolite with crystallite sizes ranging up to 5.04 μm with cactus/cabbage like structures. The quantitative analysis of the total number of acid sites was found to increase as Na2 O increases. The Na P zeolite sample with a Na2O/Si O2 molar ratio of 1.13 exhibited a large fraction of the acid sites on its external surface, contrary to that synthesized with a relevant ratio of 1.10. The optimized Na P zeolite could be successfully bestowed with excellent sorption properties of Ca(II) in aqueous solution. The kinetic parameters for Ca(II) adsorption were thoroughly investigated.
文摘Microbial electrolysis cell(MEC)is a potential technology to meet the increasing interest in finding new sources of energy that will not harm the environment.MEC is an alternative energy conversion technology for the production of biofuels.It is possible to produce hydrogen by fermenting biogenous wastes with hydrogen-producing bacteria.This study investigated the biohydrogen production from co-substrates using electrogenic bacteria such as Escherichia coli,Salmonella bongori,and Shewanella oneidensis in pure culture and as a co-culture,which has the potential to be used as co-substrate in MECs.Briefly,150 mL working-volume reactors were constructed for batch biohydrogen production.The hydrogen production rate(HPR)from the co-substrate was maximum at a ratio of 75:25 g/L with a co-culture of 2.35 mL/(L h).Fabricated a single-chamber membrane-free microelectrolysis cell to evaluate the power density,current density,voltage,HPR,chemical oxygen demand(COD)removal efficiency and Columbic efficiency.Scanning electron microscope(SEM)imaging confirmed the binding of electrogenic bacteria to anode and cathode.The efficiency of electrical conductivity of MEC was analyzed by three different electrodes,namely,nickel,copper and aluminum.The HPR was high using nickel when compared to the other two electrodes.The HPR of a single chamber using a nickel electrode was 2.8 HPR ml/L H_(2) d^(−1) and provided a power density of 17.7 mW/m^(2) at pH 7.This study suggests that the nickel cathode in a single chamber could be a promising sustainable source for stable power generation.
基金partially supported by NORTE 2020(2014-2020 North Portugal Regional Operational Program)the ERDF(European Regional Development Fund)under Grant NORTE-01-0145-FEDER-000019+7 种基金by European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No.686009by“TAMs-targeted and externally controlled nanotheranostics of triple-negative-breast-cancer(Nanother)"project UTAP-EXPL/NTec/0038/2017by“Local specific treatment of triple-negative-breast-cancer through externally triggered target-less drug carriers(MagtargetON)"project NORTE-01-0145-FEDER-031142co-funded by FCT and the ERDF through NORTE2020by 2014-2020 INTERREG Cooperation Programme Spain-Portugal(POCTEP)through the project 0624_2IQBIONEURO_6_Esupport from Raman4clinics COST Action BM1401 and Radiomag COST action TD1402the ERDF and the Spanish MINECO under project ref.PI19/00349(AES 2019)the Instituto de Salud Carlos Ⅲ for the Sara Borrell Grant(CD19/00035).
文摘Nowadays,a number of promising strategies are being developed that aim at combining diagnostic and therapeutic capabilities into clinically effective formulations.Thus,the combination of a modified release provided by an organic encapsulation and the intrinsic physico-chemical properties from an inorganic counterpart opens new perspectives in biomedical applications.Herein,a biocompatible magnetic lipid nanocomposite vehicle was developed through an efficient,green and simple method to simultaneously incorporate magnetic nanoparticles and an anticancer drug(doxorubicin)into a natural nano-matrix.The theranostic performance of the final magnetic formulation was validated in vitro and in vivo,in melanoma tumors.The systemic administration of the proposed magnetic hybrid nanocomposite carrier enhanced anti-tumoral activity through a synergistic combination of magnetic hyperthermia effects and antimitotic therapy,together with MRI reporting capability.The application of an alternating magnetic field was found to play a dual role,(i)acting as an extra layer of control(remote,on-demand)over the chemotherapy release and(ii)inducing a local thermal ablation of tumor cells.This combination of chemotherapy with thermotherapy establishes a synergistic platform for the treatment of solid malignant tumors under lower drug dosing schemes,which may realize the dual goal of reduced systemic toxicity and enhanced anti-tumoral efficacy.
