The ion exchange model of the leaching process was determined via batch leaching experiments using the Kerr model, with the selectivity coefficient experimentally determined to be 12.59×10^-10 L^2/g^2. Solute tra...The ion exchange model of the leaching process was determined via batch leaching experiments using the Kerr model, with the selectivity coefficient experimentally determined to be 12.59×10^-10 L^2/g^2. Solute transport laws of ammonium ions (NH4 +) and rare earth ions (RE^3+) in column leaching were described by the convection-dispersion equation (CDE). The source and sink in the CDE were determined by the Kerr model. The CDE with strong nonlinearity was solved using the sequential non-iterative method. Compared with the breakthrough curve of RE^3+, the correlation coefficient between the simulated and experimental curves reached 0.8724. Therefore, this method can simulate the one-dimensional column leaching of weathered crust elution-deposited rare earth ore. Moreover, the effects of different concentrations of ammonium sulfate ((NH4)2SO4) solution on the leaching rate of rare earth were analyzed. The optimal concentration of the (NH4)2SO4 solution had a linear relationship with the rare earth grade.展开更多
This paper aims to establish a mathematical model that can analyze the whole leaching kinetics process of ion-adsorption type rare earth ores.This leaching process is composed of three steps:(1)ammonium ions arrive at...This paper aims to establish a mathematical model that can analyze the whole leaching kinetics process of ion-adsorption type rare earth ores.This leaching process is composed of three steps:(1)ammonium ions arrive at the ore particle surface through the diffusion layer;(2)ammonium ions exchange with rare earth ions;and(3)rare earth ions enter into the external solution through the diffusion layer.In the leaching process,it is hypothesized that the ore particle size remains constant The process of ammonium ions and rare earth ions passing through the diffusion layer was described by the Fick law,and the reversible ion exchange process between ammonium ions and rare earth ions was described by the Kerr model,A leaching kinetics model of rare earth ions by ammonium ions was constructed.Accuracy of this kinetics model was verified with laboratory tests.It is found that the correlation coefficients of all data are greater than 0.9000.The proposed kinetics model is therefore feasible for kinetics analysis throughout the leaching process.展开更多
Column leaching experiments with ion adsorption-type rare earth ores for different lixiviant concentrations and different column heights were carried out.A mathematical model of column leaching was constructed based o...Column leaching experiments with ion adsorption-type rare earth ores for different lixiviant concentrations and different column heights were carried out.A mathematical model of column leaching was constructed based on the experimental data.Two parameters(a and b)in the model were determined according to the following methodology:the ore column was divided into several units;each unit was treated with multiple leaching steps.The leaching process was simulated as a series of batch leaching experiments.Parameter a of the model was determined based on the selectivity coefficient of the balanced batch leaching experiment.Further,the influences of ammonium sulfate concentration,rare earth grade,column height,permeability coefficient,and hydrodynamic dispersion coefficient on the extraction were analyzed.Relationships between parameter b,the ammonium sulfate concentration,and the physical and mechanical properties of the ore column,were examined using dimensional analysis.It was determined that the optimal ammonium sulfate concentration for different column heights(2.5,5.0,7.5,and 10.0 cm)using the mathematical model were 5.9,6.2,7.3,and 7.7 g/L,respectively.The mathematical model can be used to estimate the breakthrough curve,leaching rate,and leaching period of rare earth ores,to achieve optimal extraction.展开更多
The establishment of a mathematical model for the ion exchange process is key to creating a theoretical basis for the mining of ion-adsorption type rare earth ores.Ore samples from Xinfeng,Xunwu and Anyuan were used a...The establishment of a mathematical model for the ion exchange process is key to creating a theoretical basis for the mining of ion-adsorption type rare earth ores.Ore samples from Xinfeng,Xunwu and Anyuan were used as the test ore samples in the present study and equilibrium batch tests of ore sample leaching using various ammonium sulfate concentrations were performed.The results show that,after leaching,there is a negative exponential relationship between the ratio of the solid-phase rare earth ion concentration to the aqueous-phase rare earth ion concentration and the initial ammonium ion concentration.However,there is a linear relationship between the natural logarithm of the ratio of the solidphase ammonium ion concentration to the aqueous-phase ammonium ion concentration and the initial ammonium ion concentration.Based on the above two functional relationships,a two-parameter model for the equilibrium ion exchange process of ion-adsorption type rare earth ores was established.Using the established model to analyze the test data the model error for the Xunwu ore sample is found to be less than 5%.The proposed model is more accurate compared with the Kerr model.The two-parameter model proposed in this study provides theoretical support for the numerical simulation of column leaching(in-situ leaching)of ion-adsorption type rare earth ores.展开更多
Objective:To compare effect of immunoprevention or immunotherapy based on denderitic cells (DCs),or supernatants on pancreatic carcinoma and hepatocelluar carcinoma in ritro and in vivo.Methods:DCs and monouclear cell...Objective:To compare effect of immunoprevention or immunotherapy based on denderitic cells (DCs),or supernatants on pancreatic carcinoma and hepatocelluar carcinoma in ritro and in vivo.Methods:DCs and monouclear cells (immunoeffecetor cells) were stimulated with hGM-CSF,hIL-4,hTNF-α,PC3 TA or BEL7402 TA and hIL-2,then DCs and immunoeffector cells were cocultured,and supernatants were harvested.In vitro,the immunoeffector cells were divided into A0 group (without DCs stimulated),A1 group (DCs stimulated,cultured with cytokines cocktail),A2 group (DCs stimulated,cultured with cytokines cocktail and tumor antigen.DCs vaccine).Cytoxicity assay was performed with lactate dehydogenase method,In vivo,the nude mice were allocated in 3 groups:prevention group,receiving immunoeffector cells activated by DCs vaccine 2 days before inoculation with PC3 or BEL7402;treatment group,receiving immunoeffector cells activated by DCs vaccine after development of implanted tumor in all nude mice;control group,receiving equivalents amount of RPMI1640 cultured liquid.On the 45th day,all the nude mice were sacrificed and the tumor was weighed.Results:The maximal inhibition rate of the A0.A1 andA2 were 3.5%.68.1%.81.0% in the BEL7402;4.5%,33.0%.62.4% in the PC3.The differences in tumor weight among three groups were significant,but the difference were not significant between the PC3 and BEL7402.Conclusions:DCs vaccine or supernatants may play an important role in treating and preventing against malignant tumor.展开更多
Objective:To explore the effect of different fertilization time after human chorionic gonadotropin(HCG)injection on the outcome of fertilization in vitro fertilization-embryo transfer(IVF-ET).Methods:One thousand one ...Objective:To explore the effect of different fertilization time after human chorionic gonadotropin(HCG)injection on the outcome of fertilization in vitro fertilization-embryo transfer(IVF-ET).Methods:One thousand one hundred and forty IVF-ET cycles from January 2016 to August 2018 were analyzed retrospectively.According to the different fertilization time after injection of HCG divided into four groups:Group A(38.0 h~39.0 h),Group B(39.1 h~40.0 h),Group C(40.1 h~41.0 h),and Group D(41.1 h~42.0 h).The normal fertilization rate,the normal cleavage rate,the embryo utilization rate,the high-quality embryo rate,the clinical pregnancy rate,the implantation rate,and the spontaneous abortion rate were analyzed among the groups.Then we investigated the effect of different promotion methods on the outcome of fertilization during the optimal fertilization time.Results:There was no significant difference in 2PN cleavage rate,available embryo rate,clinical pregnancy rate,implantation rate and abortion rate among the four groups(P>0.05).The high-quality embryo rate in Group D(44.6%)was the highest,and was significantly different among the four groups(P<0.05).The normal fertilization rate in Group D(71.6%)was the highest,and was significantly different among the four groups(P<0.05).The normal fertilization rate(78.1%)of antagonist group was significantly higher than other groups(P<0.05).Conclusion:The different fertilization time after HCG injection have effects on high-quality embryo rate and normal fertilization rate of patients in IVF-ET.The appropriate fertilization time of patients in IVF-ET was 41 h~42 h after HCG injection in our reproductive center,improved the clinical pregnancy rate and reduced the early abortion rate.The GnRH-ant protocol is superior to other protocol in IVF-ET.展开更多
Non-Camellia tea is a part of the colorful Chinese tea culture,and is also widely used as beverage and medicine in folk for disease prevention and treatment.In this study,37 samples were collected,including 33 kinds o...Non-Camellia tea is a part of the colorful Chinese tea culture,and is also widely used as beverage and medicine in folk for disease prevention and treatment.In this study,37 samples were collected,including 33 kinds of non-Camellia teas and 4 kinds of teas(Camellia).Traditional functions of non-Camellia teas were investigated.Furthermore,non-Camellia teas of original plants were characterized and identified by molecular methods.Four candidate regions(rbcL,matK,ITS2,psbA-trnH)were amplified by polymerase chain reaction.In addition,DNA barcodes were used for the first time to discriminate the commercial non-Camellia tea and their adulterants,and to evaluate their safety.This study showed that BLASTN and the relevant phylogenetic tree are efficient tools for identification of the commercial non-Camellia tea and their adulterants.However,some sequences from original plants have not been found and there is a limitation of sequence number of original plants in GenBank.Submitting more original plant sequences to the GenBank will be helpful for evaluating the safety of non-Camellia teas.展开更多
Objective To investigate Mongolian medicinal plants called Digeda and the prescriptions in Inner Mongolia region and to establish a molecular method for authentication of Digeda Mongolian patent medicines （MPMs）. Me...Objective To investigate Mongolian medicinal plants called Digeda and the prescriptions in Inner Mongolia region and to establish a molecular method for authentication of Digeda Mongolian patent medicines （MPMs）. Methods A field investigation was conducted on traditional uses of Digeda. After interviewed traditional healers in Mongolian, ethnopharmacological information of Digeda prescriptions was recorded in detail, including names, compositions, and traditional uses. And the total DNA from 10 MPMs has been amplified by three pairs of specific primers. Specific PCR products were further identified by sequence alignment with the known sequences already submitted in GenBank or own sequences. Results Fifteen Digeda plants and 29 Digeda prescriptions with their ethnopharmacological knowledge were collected. Ten MPM samples containing Lomatogonium rotatum, Viola philippica, and Corydalis bungeana were successfully evidenced by PCR with specific bands as raw materials. Conclusion Digeda should be further investigated in ethnopharmacology, which is a fundamental step toward developing efficacious natural drugs for various diseases. PCR amplification of specific allele is an easy and economical method, which can be used to identify highly processed MPMs and will assist in monitoring their qualities and legalities.展开更多
基金Projects(51664015,41602311,51774156) supported by the National Natural Science Foundation of China
文摘The ion exchange model of the leaching process was determined via batch leaching experiments using the Kerr model, with the selectivity coefficient experimentally determined to be 12.59×10^-10 L^2/g^2. Solute transport laws of ammonium ions (NH4 +) and rare earth ions (RE^3+) in column leaching were described by the convection-dispersion equation (CDE). The source and sink in the CDE were determined by the Kerr model. The CDE with strong nonlinearity was solved using the sequential non-iterative method. Compared with the breakthrough curve of RE^3+, the correlation coefficient between the simulated and experimental curves reached 0.8724. Therefore, this method can simulate the one-dimensional column leaching of weathered crust elution-deposited rare earth ore. Moreover, the effects of different concentrations of ammonium sulfate ((NH4)2SO4) solution on the leaching rate of rare earth were analyzed. The optimal concentration of the (NH4)2SO4 solution had a linear relationship with the rare earth grade.
基金Projects supported by the National Natural Science Foundation of China(51664015,51874147)Jiangxi University of Science and Technology Qingjiang Youth Elite Support Program(JXUSTQJBJ2016007)。
文摘This paper aims to establish a mathematical model that can analyze the whole leaching kinetics process of ion-adsorption type rare earth ores.This leaching process is composed of three steps:(1)ammonium ions arrive at the ore particle surface through the diffusion layer;(2)ammonium ions exchange with rare earth ions;and(3)rare earth ions enter into the external solution through the diffusion layer.In the leaching process,it is hypothesized that the ore particle size remains constant The process of ammonium ions and rare earth ions passing through the diffusion layer was described by the Fick law,and the reversible ion exchange process between ammonium ions and rare earth ions was described by the Kerr model,A leaching kinetics model of rare earth ions by ammonium ions was constructed.Accuracy of this kinetics model was verified with laboratory tests.It is found that the correlation coefficients of all data are greater than 0.9000.The proposed kinetics model is therefore feasible for kinetics analysis throughout the leaching process.
基金the National Natural Science Foundation of China(Nos.51664015,41602311,and 51774156)the Jiangxi University of Science and Technology Qingjiang Youth Elite Support Program(No.JXUSTQJBJ2016007).
文摘Column leaching experiments with ion adsorption-type rare earth ores for different lixiviant concentrations and different column heights were carried out.A mathematical model of column leaching was constructed based on the experimental data.Two parameters(a and b)in the model were determined according to the following methodology:the ore column was divided into several units;each unit was treated with multiple leaching steps.The leaching process was simulated as a series of batch leaching experiments.Parameter a of the model was determined based on the selectivity coefficient of the balanced batch leaching experiment.Further,the influences of ammonium sulfate concentration,rare earth grade,column height,permeability coefficient,and hydrodynamic dispersion coefficient on the extraction were analyzed.Relationships between parameter b,the ammonium sulfate concentration,and the physical and mechanical properties of the ore column,were examined using dimensional analysis.It was determined that the optimal ammonium sulfate concentration for different column heights(2.5,5.0,7.5,and 10.0 cm)using the mathematical model were 5.9,6.2,7.3,and 7.7 g/L,respectively.The mathematical model can be used to estimate the breakthrough curve,leaching rate,and leaching period of rare earth ores,to achieve optimal extraction.
基金Projects supported by the National Natural Science Foundation of China(51664015,51874147)Jiangxi University of Science and Technology Qingjiang Youth Elite Support Program(JXUSTQJBJ2016007)。
文摘The establishment of a mathematical model for the ion exchange process is key to creating a theoretical basis for the mining of ion-adsorption type rare earth ores.Ore samples from Xinfeng,Xunwu and Anyuan were used as the test ore samples in the present study and equilibrium batch tests of ore sample leaching using various ammonium sulfate concentrations were performed.The results show that,after leaching,there is a negative exponential relationship between the ratio of the solid-phase rare earth ion concentration to the aqueous-phase rare earth ion concentration and the initial ammonium ion concentration.However,there is a linear relationship between the natural logarithm of the ratio of the solidphase ammonium ion concentration to the aqueous-phase ammonium ion concentration and the initial ammonium ion concentration.Based on the above two functional relationships,a two-parameter model for the equilibrium ion exchange process of ion-adsorption type rare earth ores was established.Using the established model to analyze the test data the model error for the Xunwu ore sample is found to be less than 5%.The proposed model is more accurate compared with the Kerr model.The two-parameter model proposed in this study provides theoretical support for the numerical simulation of column leaching(in-situ leaching)of ion-adsorption type rare earth ores.
文摘Objective:To compare effect of immunoprevention or immunotherapy based on denderitic cells (DCs),or supernatants on pancreatic carcinoma and hepatocelluar carcinoma in ritro and in vivo.Methods:DCs and monouclear cells (immunoeffecetor cells) were stimulated with hGM-CSF,hIL-4,hTNF-α,PC3 TA or BEL7402 TA and hIL-2,then DCs and immunoeffector cells were cocultured,and supernatants were harvested.In vitro,the immunoeffector cells were divided into A0 group (without DCs stimulated),A1 group (DCs stimulated,cultured with cytokines cocktail),A2 group (DCs stimulated,cultured with cytokines cocktail and tumor antigen.DCs vaccine).Cytoxicity assay was performed with lactate dehydogenase method,In vivo,the nude mice were allocated in 3 groups:prevention group,receiving immunoeffector cells activated by DCs vaccine 2 days before inoculation with PC3 or BEL7402;treatment group,receiving immunoeffector cells activated by DCs vaccine after development of implanted tumor in all nude mice;control group,receiving equivalents amount of RPMI1640 cultured liquid.On the 45th day,all the nude mice were sacrificed and the tumor was weighed.Results:The maximal inhibition rate of the A0.A1 andA2 were 3.5%.68.1%.81.0% in the BEL7402;4.5%,33.0%.62.4% in the PC3.The differences in tumor weight among three groups were significant,but the difference were not significant between the PC3 and BEL7402.Conclusions:DCs vaccine or supernatants may play an important role in treating and preventing against malignant tumor.
基金National Natural Science Foundation of China(No.81460236)Major Science and Technology Program of Hainan Province(No.ZDKJ2017007)Innovative Project for Postgraduate of Hainan Province(No.Hys2018-281)。
文摘Objective:To explore the effect of different fertilization time after human chorionic gonadotropin(HCG)injection on the outcome of fertilization in vitro fertilization-embryo transfer(IVF-ET).Methods:One thousand one hundred and forty IVF-ET cycles from January 2016 to August 2018 were analyzed retrospectively.According to the different fertilization time after injection of HCG divided into four groups:Group A(38.0 h~39.0 h),Group B(39.1 h~40.0 h),Group C(40.1 h~41.0 h),and Group D(41.1 h~42.0 h).The normal fertilization rate,the normal cleavage rate,the embryo utilization rate,the high-quality embryo rate,the clinical pregnancy rate,the implantation rate,and the spontaneous abortion rate were analyzed among the groups.Then we investigated the effect of different promotion methods on the outcome of fertilization during the optimal fertilization time.Results:There was no significant difference in 2PN cleavage rate,available embryo rate,clinical pregnancy rate,implantation rate and abortion rate among the four groups(P>0.05).The high-quality embryo rate in Group D(44.6%)was the highest,and was significantly different among the four groups(P<0.05).The normal fertilization rate in Group D(71.6%)was the highest,and was significantly different among the four groups(P<0.05).The normal fertilization rate(78.1%)of antagonist group was significantly higher than other groups(P<0.05).Conclusion:The different fertilization time after HCG injection have effects on high-quality embryo rate and normal fertilization rate of patients in IVF-ET.The appropriate fertilization time of patients in IVF-ET was 41 h~42 h after HCG injection in our reproductive center,improved the clinical pregnancy rate and reduced the early abortion rate.The GnRH-ant protocol is superior to other protocol in IVF-ET.
基金This research was financially supported by the“Twelfth Five-year Plan”Program supported by the Ministry of Science and Technology(2012BAI28B02).
文摘Non-Camellia tea is a part of the colorful Chinese tea culture,and is also widely used as beverage and medicine in folk for disease prevention and treatment.In this study,37 samples were collected,including 33 kinds of non-Camellia teas and 4 kinds of teas(Camellia).Traditional functions of non-Camellia teas were investigated.Furthermore,non-Camellia teas of original plants were characterized and identified by molecular methods.Four candidate regions(rbcL,matK,ITS2,psbA-trnH)were amplified by polymerase chain reaction.In addition,DNA barcodes were used for the first time to discriminate the commercial non-Camellia tea and their adulterants,and to evaluate their safety.This study showed that BLASTN and the relevant phylogenetic tree are efficient tools for identification of the commercial non-Camellia tea and their adulterants.However,some sequences from original plants have not been found and there is a limitation of sequence number of original plants in GenBank.Submitting more original plant sequences to the GenBank will be helpful for evaluating the safety of non-Camellia teas.
基金National Natural Science Foundation of China(81160504,81060372)"Twelfth Five-year Plan"Program supported by the Ministry of Science and Technology(2012BAI28B02)Guangxi Natural Science Foundation of China(2011GXNSFD018037)
文摘Objective To investigate Mongolian medicinal plants called Digeda and the prescriptions in Inner Mongolia region and to establish a molecular method for authentication of Digeda Mongolian patent medicines （MPMs）. Methods A field investigation was conducted on traditional uses of Digeda. After interviewed traditional healers in Mongolian, ethnopharmacological information of Digeda prescriptions was recorded in detail, including names, compositions, and traditional uses. And the total DNA from 10 MPMs has been amplified by three pairs of specific primers. Specific PCR products were further identified by sequence alignment with the known sequences already submitted in GenBank or own sequences. Results Fifteen Digeda plants and 29 Digeda prescriptions with their ethnopharmacological knowledge were collected. Ten MPM samples containing Lomatogonium rotatum, Viola philippica, and Corydalis bungeana were successfully evidenced by PCR with specific bands as raw materials. Conclusion Digeda should be further investigated in ethnopharmacology, which is a fundamental step toward developing efficacious natural drugs for various diseases. PCR amplification of specific allele is an easy and economical method, which can be used to identify highly processed MPMs and will assist in monitoring their qualities and legalities.
