This review summarizes the recent advances on the application of ^(57)Fe Mössbauer spectrometry to study the magnetic and phase characteristics of Nd–Fe–B-based permanent magnets. First of all, the hyperfine st...This review summarizes the recent advances on the application of ^(57)Fe Mössbauer spectrometry to study the magnetic and phase characteristics of Nd–Fe–B-based permanent magnets. First of all, the hyperfine structures of the Ce_(2)Fe_(14)B,(Ce,Nd)_(2)Fe_(14)B and MM_(2)Fe_(14)B phases are well-defined by using the model based on the Wigner-Seitz analysis of the crystal structure. The results show that the isomer shift δ and the quadrupole splitting öEQ of those 2:14:1 phases show minor changes with the Nd content, while the hyperfine field Bhfincreases monotonically with increasing Nd content and its value is influenced by the element segregation and phase separation in the 2:14:1 phase. Then, the hyperfine structures of the low fraction secondary phases are determined by the ^(57)Fe Mössbauer spectrometry due to its high sensitivity. On this basis,the content, magnetic behavior, and magnetization of the REFe_(2) phase, the amorphous grain boundary(GB) phase, and the amorphous worm-like phase, as well as their effects on the magnetic properties, are systematically studied.展开更多
The molar heat capacities of La2Mo209 and La1.9Sr0.1MO209-δ were obtained using the differential scanning calorimetry （DSC） technique in a temperature range from 298 to 1473 K. The DSC curve of La2Mo209 showed an e...The molar heat capacities of La2Mo209 and La1.9Sr0.1MO209-δ were obtained using the differential scanning calorimetry （DSC） technique in a temperature range from 298 to 1473 K. The DSC curve of La2Mo209 showed an endothermal peak around 834 K corresponding to a first-order monoclinic-cubic phase transition, and the enthalpy change accompanying this phase transition is 5.99 kJ/mol. No evident endothermal peak existed in the DSC curve of La1.9Sr0.1MO209-δ, but a broad thermal anomaly existed in its heat capacity curve at around 832 K. In addition, the heat capacity values of La2Mo209 and La1.9Sr0.1MO209-δ began to decrease at 1196 and 1330 K, respectively. The non-transitional heat capacity values of La2Mo209 and La1.9Sr0.1MO209-δ were formulated using multiple regression analysis in two temperature ranges.展开更多
The hydrologic simulation of a catchment area, described as the transformation of rainfall into runoff, generally uses hydrologic model. This work opts for the global conceptual hydrologic model GR2M, a monthly time s...The hydrologic simulation of a catchment area, described as the transformation of rainfall into runoff, generally uses hydrologic model. This work opts for the global conceptual hydrologic model GR2M, a monthly time step model, to study the Kouilou-Niari basin, the second most important ones of the Republic of Congo. This includes two parameters to model the hydrologic behavior of a catchment area. The choice of the conceptual model GR2M is justified by the reduced number of parameters and the monthly time scale. The objective of this study is to determine the characteristic parameters of the GR2M model, by a calibrating and a validating procedure. The use of these parameters enables to follow the evolution of the water resources from the climatic variables. It has been first carried out a characterization of some physical, geological and climatic factors governing the flow, by dealing with the main climatic variables which constitute the inputs of the hydrologic model. Then, a hydrologic rainfall-runoff modeling allows to calibrate and validate the model at monthly time scale. Taking into account the number of parameters involved in hydrologic processes and the complexity of the cathment area, this model gives acceptable results throughout the Kouilou-Niari basin. The values of the Nash-Sutcliffe criterion and those of the correlation coefficient obtained are greater than 80% in validation, which explains the performance and robustness of the GR2M model on this basin.展开更多
本文利用差式扫描量热法,测定了邻二氯苯/间二氯苯、间二氯苯/对二氯苯、1,2,4-三氯苯/邻二氯苯、1,2,4-三氯苯/间二氯苯和1、2、4-三氯苯/对二氯苯等5个二元物系的固液平衡关系,并按以下方程进行了数据拟合: T=T<sub>m</sub&g...本文利用差式扫描量热法,测定了邻二氯苯/间二氯苯、间二氯苯/对二氯苯、1,2,4-三氯苯/邻二氯苯、1,2,4-三氯苯/间二氯苯和1、2、4-三氯苯/对二氯苯等5个二元物系的固液平衡关系,并按以下方程进行了数据拟合: T=T<sub>m</sub><sup>*</sup>[1+sum from j=1 to n a<sub>j</sub>（x<sub>1</sub>-x<sub>1</sub><sup>*</sup>）<sup>j</sup>]式中,T<sub>m</sub><sup>*</sup>为纯物质的熔点,x<sub>1</sub><sup>*</sup>为T<sub>m</sub><sup>*</sup>下组分1的摩尔分率,a<sub>j</sub>为拟合系数。通过按不同比例配制的邻、间、对二氯苯以及1,2,4-三氯苯拟二元相图,测出了下列物系三元固液平衡温度-组成关系:邻二氯苯/间二氯苯/对二氯苯、邻二氯苯/对二氯苯/1,2,4-三氯苯和邻二氯苯/间二氯苯/1,2,4-三氯苯。展开更多
目的研究G_(2)/S期应答相关蛋白1(G_(2) and S phase-expressed protein 1,GTSE1)在肝细胞癌(hepatocellular carcinoma,HCC)中的表达、免疫学作用和预后分析,及其潜在作用机制。方法使用公共数据库癌症基因组图谱(The Cancer Genome At...目的研究G_(2)/S期应答相关蛋白1(G_(2) and S phase-expressed protein 1,GTSE1)在肝细胞癌(hepatocellular carcinoma,HCC)中的表达、免疫学作用和预后分析,及其潜在作用机制。方法使用公共数据库癌症基因组图谱(The Cancer Genome Atlas,TCGA)提供的数据,用Kaplan-Meier、肿瘤免疫评估资源(Tumor Immune Estimation Resource,TIMER)数据库和基因表达谱交互分析(Gene Expression Profiling Interactive Analysis,GEPIA)数据库进行GTSE1基因表达、免疫学作用及预后分析,通过免疫组化实验验证GTSE1在临床样本中的表达,应用R软件对GTSE1相关差异基因进行基因本体(gene ontology,GO)和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析。结果GTSE1在人类癌组织中显著高表达,且与肝细胞癌预后不良显著相关(P<0.05);GTSE1基因表达与HCC中浸润性免疫细胞的丰度显著相关(P<0.001)。GTSE1相关的差异表达基因主要富集于核分裂、细胞器裂变、离子通道活性等基因模块;其参与的信号通路主要包括神经活性配体-受体的相互作用、细胞周期等。结论GTSE1在HCC中的表达显著上调并与患者预后不良显著相关,且在免疫细胞浸润中发挥重要作用,可作为HCC的预后标志物和免疫治疗靶点。展开更多
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(Grant Nos.LY20E010002,LR18E010001,and LD19E010001)the National Natural Science Foundation of China(Grant Nos.U1704253 and 51801047)+2 种基金Liaoning Revitalization Talents Program(Grant No.XLYC1807177)the Key Research and Development plan of Zhejiang Province,China(Grant No.2020C05014)Ten Thousand Talents Plan of Zhejiang Province,China(Grant No.2018R52003)。
文摘This review summarizes the recent advances on the application of ^(57)Fe Mössbauer spectrometry to study the magnetic and phase characteristics of Nd–Fe–B-based permanent magnets. First of all, the hyperfine structures of the Ce_(2)Fe_(14)B,(Ce,Nd)_(2)Fe_(14)B and MM_(2)Fe_(14)B phases are well-defined by using the model based on the Wigner-Seitz analysis of the crystal structure. The results show that the isomer shift δ and the quadrupole splitting öEQ of those 2:14:1 phases show minor changes with the Nd content, while the hyperfine field Bhfincreases monotonically with increasing Nd content and its value is influenced by the element segregation and phase separation in the 2:14:1 phase. Then, the hyperfine structures of the low fraction secondary phases are determined by the ^(57)Fe Mössbauer spectrometry due to its high sensitivity. On this basis,the content, magnetic behavior, and magnetization of the REFe_(2) phase, the amorphous grain boundary(GB) phase, and the amorphous worm-like phase, as well as their effects on the magnetic properties, are systematically studied.
基金This work was financially supported by the National Natural Science Foundation of China (No.50604002).
文摘The molar heat capacities of La2Mo209 and La1.9Sr0.1MO209-δ were obtained using the differential scanning calorimetry （DSC） technique in a temperature range from 298 to 1473 K. The DSC curve of La2Mo209 showed an endothermal peak around 834 K corresponding to a first-order monoclinic-cubic phase transition, and the enthalpy change accompanying this phase transition is 5.99 kJ/mol. No evident endothermal peak existed in the DSC curve of La1.9Sr0.1MO209-δ, but a broad thermal anomaly existed in its heat capacity curve at around 832 K. In addition, the heat capacity values of La2Mo209 and La1.9Sr0.1MO209-δ began to decrease at 1196 and 1330 K, respectively. The non-transitional heat capacity values of La2Mo209 and La1.9Sr0.1MO209-δ were formulated using multiple regression analysis in two temperature ranges.
文摘The hydrologic simulation of a catchment area, described as the transformation of rainfall into runoff, generally uses hydrologic model. This work opts for the global conceptual hydrologic model GR2M, a monthly time step model, to study the Kouilou-Niari basin, the second most important ones of the Republic of Congo. This includes two parameters to model the hydrologic behavior of a catchment area. The choice of the conceptual model GR2M is justified by the reduced number of parameters and the monthly time scale. The objective of this study is to determine the characteristic parameters of the GR2M model, by a calibrating and a validating procedure. The use of these parameters enables to follow the evolution of the water resources from the climatic variables. It has been first carried out a characterization of some physical, geological and climatic factors governing the flow, by dealing with the main climatic variables which constitute the inputs of the hydrologic model. Then, a hydrologic rainfall-runoff modeling allows to calibrate and validate the model at monthly time scale. Taking into account the number of parameters involved in hydrologic processes and the complexity of the cathment area, this model gives acceptable results throughout the Kouilou-Niari basin. The values of the Nash-Sutcliffe criterion and those of the correlation coefficient obtained are greater than 80% in validation, which explains the performance and robustness of the GR2M model on this basin.
文摘本文利用差式扫描量热法,测定了邻二氯苯/间二氯苯、间二氯苯/对二氯苯、1,2,4-三氯苯/邻二氯苯、1,2,4-三氯苯/间二氯苯和1、2、4-三氯苯/对二氯苯等5个二元物系的固液平衡关系,并按以下方程进行了数据拟合: T=T<sub>m</sub><sup>*</sup>[1+sum from j=1 to n a<sub>j</sub>（x<sub>1</sub>-x<sub>1</sub><sup>*</sup>）<sup>j</sup>]式中,T<sub>m</sub><sup>*</sup>为纯物质的熔点,x<sub>1</sub><sup>*</sup>为T<sub>m</sub><sup>*</sup>下组分1的摩尔分率,a<sub>j</sub>为拟合系数。通过按不同比例配制的邻、间、对二氯苯以及1,2,4-三氯苯拟二元相图,测出了下列物系三元固液平衡温度-组成关系:邻二氯苯/间二氯苯/对二氯苯、邻二氯苯/对二氯苯/1,2,4-三氯苯和邻二氯苯/间二氯苯/1,2,4-三氯苯。
文摘目的研究G_(2)/S期应答相关蛋白1(G_(2) and S phase-expressed protein 1,GTSE1)在肝细胞癌(hepatocellular carcinoma,HCC)中的表达、免疫学作用和预后分析,及其潜在作用机制。方法使用公共数据库癌症基因组图谱(The Cancer Genome Atlas,TCGA)提供的数据,用Kaplan-Meier、肿瘤免疫评估资源(Tumor Immune Estimation Resource,TIMER)数据库和基因表达谱交互分析(Gene Expression Profiling Interactive Analysis,GEPIA)数据库进行GTSE1基因表达、免疫学作用及预后分析,通过免疫组化实验验证GTSE1在临床样本中的表达,应用R软件对GTSE1相关差异基因进行基因本体(gene ontology,GO)和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析。结果GTSE1在人类癌组织中显著高表达,且与肝细胞癌预后不良显著相关(P<0.05);GTSE1基因表达与HCC中浸润性免疫细胞的丰度显著相关(P<0.001)。GTSE1相关的差异表达基因主要富集于核分裂、细胞器裂变、离子通道活性等基因模块;其参与的信号通路主要包括神经活性配体-受体的相互作用、细胞周期等。结论GTSE1在HCC中的表达显著上调并与患者预后不良显著相关,且在免疫细胞浸润中发挥重要作用,可作为HCC的预后标志物和免疫治疗靶点。
