The products of monoammonium phosphate containing Cr^3+resulted in disqualification,and further posed a serious threat to ecological environment and human beings.Herein,the porous adsorbent of fluor(calcium silicate)c...The products of monoammonium phosphate containing Cr^3+resulted in disqualification,and further posed a serious threat to ecological environment and human beings.Herein,the porous adsorbent of fluor(calcium silicate)composites(FCSc)was prepared by hydrothermal method using diatomaceous earth,hydrated lime and additive(NaF)as raw materials,which was characterized and used for the removal of Cr^3+from monoammonium phosphate solutions.The effects of different parameters,such as solution pH,initial Cr^3+concentration,temperature and contact time on the adsorption of Cr^3+onto FCSc were investigated in details.The results indicated that the adsorption process was in agreement with the pseudo-second-order kinetic model and Freundlich isotherm.The spontaneous and endothermic nature of the adsorption process was obtained by analyzing various thermodynamic parameters(△G0,△H0,and△S0).In addition,computational monte carlo simulations between Cr3+ions and FCSc were conducted to elucidate the adsorption mechanism.Such kind of porous adsorbent provided a potential application in the removal of impurities from monoammonium phosphate industry.展开更多
The novel chromium(Ⅲ) complex with salicylaldehyde semicarbazone was synthesized and characterized by IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space ...The novel chromium(Ⅲ) complex with salicylaldehyde semicarbazone was synthesized and characterized by IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space group Pbca with a = 8.9849(13), b = 12.0475(16), c = 34.522(5)A, V = 3736.9(9)A3, Z = 8, C16H18C1CrN6O5, Mr= 461.81, De= 1.642 g/cm^3, F(000) = 1896,A(MoKα) = 0.799 mm^-1, the final R = 0.0370 and wR = 0.0827 for 2908 observed reflections with I 〉 2σ(I). The interaction between the chromium(Ⅲ) complex with calf thymus DNA (Ct-DNA) has been investigated by absorption spectroscopy, fluorescence spectroscopy and viscosity measurements. The results indicated that the complex was bonded to Ct-DNA through a non-classical intercalative mode.展开更多
In this work,a solely gravity and capillary force-driven flow chemiluminescence(GCF-CL)paper-based microfuidic device has been proved for the first time as a new platforn for inex-pensive,usable,mini mally instrumente...In this work,a solely gravity and capillary force-driven flow chemiluminescence(GCF-CL)paper-based microfuidic device has been proved for the first time as a new platforn for inex-pensive,usable,mini mally instrumented dynamic chemiluninescence(CL)detection of chromium(Ⅲ)[Cr(Ⅲ)],where an appropriate angle of inclination between the loading and detection zones on the paper produces a rapid flow of CL prompt solution through the paper charnel.For this study,we use a cost-effective paper device that is manufactured by a simple wax screen-printing method,while the signal generated from the Cr(Ⅲ)-catalyzed oxidation of luminol by H_(2)O_(2) is recorded by a low-cost and luggable CCD camera.A series of GCF-CL affecting factors have been evaluated carefully.At optimal conditions,two linear relationships between GCF-CL intensities and the logarithms of Cr(Ⅲ)concentrations are obtained in the concentration mnges of 0.025-35 mg/L and 50-500 mg/L separately,with the detection limit of 0.0245mg/L for a les than 30s assay,and relative standard deviations(RSDs)of 38%,4.5%and 2.3%for 0.75,5 and 50 mg/L of Cr(Ⅲ)(n=8).The above results indicate that the GCF-CL paper-based microfluidic device possesses a receivable sensitivity,dynamic range,storage stability and reproducibility.Finally,the developed GCF-CL is utilized for Cr(Ⅲ)detection in real water samples.展开更多
Objectives:This study used Deinococcus radiodurans,which is extremely resistant to oxidative damage,genotoxic chemicals,high levels of ionising and ultraviolet radiation and drying,and its Vitreoscilla haemoglobin(vgb...Objectives:This study used Deinococcus radiodurans,which is extremely resistant to oxidative damage,genotoxic chemicals,high levels of ionising and ultraviolet radiation and drying,and its Vitreoscilla haemoglobin(vgb)gene-cloned recombinant with the vgb−recombinant strain as a control.In addition to the conditions wherein bacteria have an optimum Cr(Ⅲ)biosorption capacity,the contribution of the vgb gene to the biosorption ability of the bacteria has been investigated by providing the organism with a more oxygenic environment.Methods:Bacteria were produced and metal stock solution was prepared.To determine the Cr(Ⅲ)removal capacities of wild and recombinant D.radiodurans strains,the residual metal concentration in aqueous media at the beginning and after biosorption was determined in Atomic Absorption Spectrophotometer.Some optimal conditions were created for the biosorption conditions to occur.Conclusions:The optimisation tests showed that Cr(Ⅲ)reached the highest biosorption capacity within 15 minutes at a metal concentration of 2,000 ppm,30°C,pH 5.0 and 150 rpm stirring speed in all the three bacteria.The vgb gene had no significant contribution to the biosorption capacity.展开更多
基金the National Natural Science Foundation of China(U1633203)the Major Project of the Civil Aviation Administration of China(J2020-108)。
文摘The products of monoammonium phosphate containing Cr^3+resulted in disqualification,and further posed a serious threat to ecological environment and human beings.Herein,the porous adsorbent of fluor(calcium silicate)composites(FCSc)was prepared by hydrothermal method using diatomaceous earth,hydrated lime and additive(NaF)as raw materials,which was characterized and used for the removal of Cr^3+from monoammonium phosphate solutions.The effects of different parameters,such as solution pH,initial Cr^3+concentration,temperature and contact time on the adsorption of Cr^3+onto FCSc were investigated in details.The results indicated that the adsorption process was in agreement with the pseudo-second-order kinetic model and Freundlich isotherm.The spontaneous and endothermic nature of the adsorption process was obtained by analyzing various thermodynamic parameters(△G0,△H0,and△S0).In addition,computational monte carlo simulations between Cr3+ions and FCSc were conducted to elucidate the adsorption mechanism.Such kind of porous adsorbent provided a potential application in the removal of impurities from monoammonium phosphate industry.
基金Supported by the Scientific Research Common Program of Beijing Municipal Commission of Education, PRC (KM200510028005)
文摘The novel chromium(Ⅲ) complex with salicylaldehyde semicarbazone was synthesized and characterized by IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space group Pbca with a = 8.9849(13), b = 12.0475(16), c = 34.522(5)A, V = 3736.9(9)A3, Z = 8, C16H18C1CrN6O5, Mr= 461.81, De= 1.642 g/cm^3, F(000) = 1896,A(MoKα) = 0.799 mm^-1, the final R = 0.0370 and wR = 0.0827 for 2908 observed reflections with I 〉 2σ(I). The interaction between the chromium(Ⅲ) complex with calf thymus DNA (Ct-DNA) has been investigated by absorption spectroscopy, fluorescence spectroscopy and viscosity measurements. The results indicated that the complex was bonded to Ct-DNA through a non-classical intercalative mode.
基金supported by the National Natural Science Foundation of China(No.81571765)Guangzhou Science and Technology Program(No.2014J4100030)Guangdong Science and Technology Program(Nos.2014A020212503 and 2016A020215143).
文摘In this work,a solely gravity and capillary force-driven flow chemiluminescence(GCF-CL)paper-based microfuidic device has been proved for the first time as a new platforn for inex-pensive,usable,mini mally instrumented dynamic chemiluninescence(CL)detection of chromium(Ⅲ)[Cr(Ⅲ)],where an appropriate angle of inclination between the loading and detection zones on the paper produces a rapid flow of CL prompt solution through the paper charnel.For this study,we use a cost-effective paper device that is manufactured by a simple wax screen-printing method,while the signal generated from the Cr(Ⅲ)-catalyzed oxidation of luminol by H_(2)O_(2) is recorded by a low-cost and luggable CCD camera.A series of GCF-CL affecting factors have been evaluated carefully.At optimal conditions,two linear relationships between GCF-CL intensities and the logarithms of Cr(Ⅲ)concentrations are obtained in the concentration mnges of 0.025-35 mg/L and 50-500 mg/L separately,with the detection limit of 0.0245mg/L for a les than 30s assay,and relative standard deviations(RSDs)of 38%,4.5%and 2.3%for 0.75,5 and 50 mg/L of Cr(Ⅲ)(n=8).The above results indicate that the GCF-CL paper-based microfluidic device possesses a receivable sensitivity,dynamic range,storage stability and reproducibility.Finally,the developed GCF-CL is utilized for Cr(Ⅲ)detection in real water samples.
基金This study was supported by Inonu University Scientific Research Projects Coordination Unit(project number:2012-192).
文摘Objectives:This study used Deinococcus radiodurans,which is extremely resistant to oxidative damage,genotoxic chemicals,high levels of ionising and ultraviolet radiation and drying,and its Vitreoscilla haemoglobin(vgb)gene-cloned recombinant with the vgb−recombinant strain as a control.In addition to the conditions wherein bacteria have an optimum Cr(Ⅲ)biosorption capacity,the contribution of the vgb gene to the biosorption ability of the bacteria has been investigated by providing the organism with a more oxygenic environment.Methods:Bacteria were produced and metal stock solution was prepared.To determine the Cr(Ⅲ)removal capacities of wild and recombinant D.radiodurans strains,the residual metal concentration in aqueous media at the beginning and after biosorption was determined in Atomic Absorption Spectrophotometer.Some optimal conditions were created for the biosorption conditions to occur.Conclusions:The optimisation tests showed that Cr(Ⅲ)reached the highest biosorption capacity within 15 minutes at a metal concentration of 2,000 ppm,30°C,pH 5.0 and 150 rpm stirring speed in all the three bacteria.The vgb gene had no significant contribution to the biosorption capacity.