Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to...Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to produce it through solid state reaction from 900℃ to 1300℃. The conducted reaction was monitored by XRD step by step. Amount of Wollastonite formed at every temperature was also studied to some extent. Analyses of the obtained data indicated that the target mineral formation was quite effective and almost proportional to a rise in temperature up to 1200℃. The results from both, XRD and chemical analysis were found in fair agreement with one another展开更多
Photoneutron cross-section(PNCS)data are important in various current and emerging applications.Although a few sophis-ticated methods have been developed,there is still an urgent need to study the PNCS data.In this st...Photoneutron cross-section(PNCS)data are important in various current and emerging applications.Although a few sophis-ticated methods have been developed,there is still an urgent need to study the PNCS data.In this study,we propose the extraction of PNCS distributions using a combination of gamma activation and reaction yield ratio methods.To verify the validity of the proposed extraction method,experiments for generating^(62,64)Cu and^(85m,87m)Sr isotopes via laser-induced pho-toneutron reactions were performed,and the reaction yields of these isotopes were obtained.Using the proposed extraction method,the PNCS distributions of^(63)Cu and^(86)Sr isotopes(leading to^(85m)Sr isotope production)were successfully extracted.These extracted PNCS distributions were benchmarked against available PNCS data or TALYS calculations,demonstrating the validity of the proposed extraction method.Potential applications for predicting the PNCS distributions of the 30 iso-topes are further introduced.We conclude that the proposed extraction method is an effective complement to the available sophisticated methods for measuring and evaluating PNCS data.展开更多
The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of ...The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of the yield stress and the Soret effect. The governing boundary layer equations and boundary conditions are cast into a dimen- sionless form by similarity transformations, and the resulting system of equations is solved by a finite difference method. The results are preSented and discussed for concentration profiles, as well as the Nusselt number and the Sherwood number for various values of the parameters, which govern the problem. The results obtained show that the flow field is influenced appreciably by the presence of the chemical reaction parameter γ the order of.the chemical reaction parameter m, the Soret number St, the buoyancy ratio N, the Lewis number Le, and the dimensionless rheological parameter Ω.展开更多
Zirconium metal-organic frameworks（Zr-MOFs） represent the most promising candidates among MOFs for industrial utilizations owing to their high porosity and excellent stability. However, the efficient synthesis of Zr...Zirconium metal-organic frameworks（Zr-MOFs） represent the most promising candidates among MOFs for industrial utilizations owing to their high porosity and excellent stability. However, the efficient synthesis of Zr-MOFs combining with continuous production, high productivity and good product quality still remains a critical issue for practical applications. Herein, we report an efficient method of synthesizing a series of Zr-MOFs through a microdroplet flow reaction, which is more accommodate the requirements of industrial production. Four types of Zr-based MOFs with different ligands and topologies（MOF-801, MOF-804, DUT-67 and MOF-808） were produced as a pure phase of high quality crystalline with uniform morphologies. Furthermore, this series of Zr-MOFs were obtained in a continuous way and at a space-time yield（STY） highly up to 367.2 kg m-3 d-1. These MOFs exhibit the similar pore structure and thermal stability with that prepared from conventional solvothermal synthesis. CO2 sorption studies on these MOFs demonstrate that the hydroxyl groups on ligand can render MOFs with high CO2/N2 selectivity.展开更多
Metal-fluorine(MF)diatomic molecules,such as YbF and PbF,are extensively utilized in precision spectroscopy and fundamental physics applications.For instance,they are suitable candidates for the search of electric dip...Metal-fluorine(MF)diatomic molecules,such as YbF and PbF,are extensively utilized in precision spectroscopy and fundamental physics applications.For instance,they are suitable candidates for the search of electric dipole moments(EDMs)and the investigation of laser cooling systems.Studying how to generate these molecules effectively and productively is of significant importance.In the present work,we focus on the generation of YbF and PbF through chemical reactions involving Yb,Pb atoms ablated from an Yb-,Pb-metal targets and two most commonly used fluorine-containing gases,SF_(6)and CF_(4).The reactions are investigated theoretically using density functional theory(DFT)and experimentally employing the laser-ablation/laser-induced fluorescence(LIF)technique to compare the efficiencies of YbF and PbF molecule generation.Computational results suggest that when generating PbF,the use of SF_(6)as the fluorine gas enhances the yield in comparison to CF_(4),which is consistent with our experimental results.On the contrary,for YbF,while theoretical calculations similarly advocate for SF_(6)yielding higher yields,the experimental results contradict this conclusion.Furthermore,theoretical predictions propose that metal atoms in an excited state can promote the progress of the reaction.展开更多
A novel zoledronic acid derivative,1-hydroxy-2-(2-butyl-1H-imidazole-1-yl)-ethylidene-l,l- diphosphonic acid(BIDP),was synthesized and labeled with ^(99)Tc^m.The detailed kinetic study on the labeling reaction between...A novel zoledronic acid derivative,1-hydroxy-2-(2-butyl-1H-imidazole-1-yl)-ethylidene-l,l- diphosphonic acid(BIDP),was synthesized and labeled with ^(99)Tc^m.The detailed kinetic study on the labeling reaction between BIDP and ^(99)Tc^m was carried out.The results indicated that the reaction rate constants k were 0.0258,0.0268, 0.0305,0.0323,0.0351 and 0.0384 min^(-1)at 0℃,5℃,10℃,15℃,20℃and 25℃,respectively.From the Arrhenius equation k=A·e^(-E_Δ/(RT)),the activation energy E_a of the labeling reaction was calculated to be 10.45 kJ/mol.And the correlation between k and temperature(T)was also deduced as In k=-1258.8×(l/T)+0.9531.In addition,it was found that in order to get a high radiolabeling yield(RLY)(>90%),the reaction temperature must be up to 12℃.展开更多
文摘Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to produce it through solid state reaction from 900℃ to 1300℃. The conducted reaction was monitored by XRD step by step. Amount of Wollastonite formed at every temperature was also studied to some extent. Analyses of the obtained data indicated that the target mineral formation was quite effective and almost proportional to a rise in temperature up to 1200℃. The results from both, XRD and chemical analysis were found in fair agreement with one another
基金This work was supported by the National Key R&D Program of China(No.2022YFA1603300)the National Natural Science Foundation of China(Nos.U2230133)+2 种基金the Independent Research Project of the Key Laboratory of Plasma Physics,CAEP(No.JCKYS2021212009)the Open Fund of the Key Laboratory of Nuclear Data,CIAE(No.JCKY2022201C152)Hengyang Municipal Science and Technology Project(No.202150054076).
文摘Photoneutron cross-section(PNCS)data are important in various current and emerging applications.Although a few sophis-ticated methods have been developed,there is still an urgent need to study the PNCS data.In this study,we propose the extraction of PNCS distributions using a combination of gamma activation and reaction yield ratio methods.To verify the validity of the proposed extraction method,experiments for generating^(62,64)Cu and^(85m,87m)Sr isotopes via laser-induced pho-toneutron reactions were performed,and the reaction yields of these isotopes were obtained.Using the proposed extraction method,the PNCS distributions of^(63)Cu and^(86)Sr isotopes(leading to^(85m)Sr isotope production)were successfully extracted.These extracted PNCS distributions were benchmarked against available PNCS data or TALYS calculations,demonstrating the validity of the proposed extraction method.Potential applications for predicting the PNCS distributions of the 30 iso-topes are further introduced.We conclude that the proposed extraction method is an effective complement to the available sophisticated methods for measuring and evaluating PNCS data.
文摘The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of the yield stress and the Soret effect. The governing boundary layer equations and boundary conditions are cast into a dimen- sionless form by similarity transformations, and the resulting system of equations is solved by a finite difference method. The results are preSented and discussed for concentration profiles, as well as the Nusselt number and the Sherwood number for various values of the parameters, which govern the problem. The results obtained show that the flow field is influenced appreciably by the presence of the chemical reaction parameter γ the order of.the chemical reaction parameter m, the Soret number St, the buoyancy ratio N, the Lewis number Le, and the dimensionless rheological parameter Ω.
基金supported by grants from the National Natural Science Foundation of China (Nos. 21401215, 21473254)the Special Project Fund of "Taishan Scholars" of Shandong Province (No. ts201511017)
文摘Zirconium metal-organic frameworks（Zr-MOFs） represent the most promising candidates among MOFs for industrial utilizations owing to their high porosity and excellent stability. However, the efficient synthesis of Zr-MOFs combining with continuous production, high productivity and good product quality still remains a critical issue for practical applications. Herein, we report an efficient method of synthesizing a series of Zr-MOFs through a microdroplet flow reaction, which is more accommodate the requirements of industrial production. Four types of Zr-based MOFs with different ligands and topologies（MOF-801, MOF-804, DUT-67 and MOF-808） were produced as a pure phase of high quality crystalline with uniform morphologies. Furthermore, this series of Zr-MOFs were obtained in a continuous way and at a space-time yield（STY） highly up to 367.2 kg m-3 d-1. These MOFs exhibit the similar pore structure and thermal stability with that prepared from conventional solvothermal synthesis. CO2 sorption studies on these MOFs demonstrate that the hydroxyl groups on ligand can render MOFs with high CO2/N2 selectivity.
基金supported by the National Natural Science Foundation of China(No.11674096 and No.21973030).
文摘Metal-fluorine(MF)diatomic molecules,such as YbF and PbF,are extensively utilized in precision spectroscopy and fundamental physics applications.For instance,they are suitable candidates for the search of electric dipole moments(EDMs)and the investigation of laser cooling systems.Studying how to generate these molecules effectively and productively is of significant importance.In the present work,we focus on the generation of YbF and PbF through chemical reactions involving Yb,Pb atoms ablated from an Yb-,Pb-metal targets and two most commonly used fluorine-containing gases,SF_(6)and CF_(4).The reactions are investigated theoretically using density functional theory(DFT)and experimentally employing the laser-ablation/laser-induced fluorescence(LIF)technique to compare the efficiencies of YbF and PbF molecule generation.Computational results suggest that when generating PbF,the use of SF_(6)as the fluorine gas enhances the yield in comparison to CF_(4),which is consistent with our experimental results.On the contrary,for YbF,while theoretical calculations similarly advocate for SF_(6)yielding higher yields,the experimental results contradict this conclusion.Furthermore,theoretical predictions propose that metal atoms in an excited state can promote the progress of the reaction.
基金Supported by National Natural Science Foundation of China(Nos.20801024 and 21001055)Natural Science Foundation of J iangsu Province(No.BK2009077)Science Foundation of Health Department of Jiangsu Province(No.H200963)
文摘A novel zoledronic acid derivative,1-hydroxy-2-(2-butyl-1H-imidazole-1-yl)-ethylidene-l,l- diphosphonic acid(BIDP),was synthesized and labeled with ^(99)Tc^m.The detailed kinetic study on the labeling reaction between BIDP and ^(99)Tc^m was carried out.The results indicated that the reaction rate constants k were 0.0258,0.0268, 0.0305,0.0323,0.0351 and 0.0384 min^(-1)at 0℃,5℃,10℃,15℃,20℃and 25℃,respectively.From the Arrhenius equation k=A·e^(-E_Δ/(RT)),the activation energy E_a of the labeling reaction was calculated to be 10.45 kJ/mol.And the correlation between k and temperature(T)was also deduced as In k=-1258.8×(l/T)+0.9531.In addition,it was found that in order to get a high radiolabeling yield(RLY)(>90%),the reaction temperature must be up to 12℃.
