The AD 79 eruption of Somma-Vesuvius completely buried the ancient landscape around Pompeii (Italy) to some extent conserving the pre-AD 79 Roman paleosols of the Sarno River plain. To estimate potential post-burial s...The AD 79 eruption of Somma-Vesuvius completely buried the ancient landscape around Pompeii (Italy) to some extent conserving the pre-AD 79 Roman paleosols of the Sarno River plain. To estimate potential post-burial soil developments of these paleosols detailed soil liquid and solid phase analysis were carried out. Firstly, an in-situ soil hydrological monitoring was conducted within a pre-AD 79 paleosol in natural undisturbed stratification. The results show that soil water flow and nutrient transport from the overlying volcanic deposits into the pre-AD 79 paleosol take place. Secondly, to estimate their influence on the paleosol’s mineral soil properties, the solid phase of four pre-AD 79 paleosols and associated modern unburied soils were analysed and compared. By combining the data from the soil liquid and solid phase analysis, potential post-burial changes in the paleosols were estimated. Finally, a rise of the mean groundwater table was determined since AD 79. This distinguishes the Sarno River plain into two different zones of post-burial soil developments: 1) lower altitudes where formerly terrestrial paleosols are now influenced by groundwater dynamics and 2) higher altitudes where the paleosols are still part of the vadose zone and rather influenced by infiltration water or interflow. Thus, the mechanism of potential post-burial soil development being active in the pre-AD 79 paleosols is not uniform for the entire Sarno River plain but strongly depends on the paleotopographic situation.展开更多
To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain siz...To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain size of Li FeP O4/C decreases,and the impurities in Li Fe PO4/C composites reduce to a great extent. It makes great sense to the mass industrial production. The optimum synthesis conditions determined in this work are based on the orthogonal experiments. The samples synthesized in a scale of 500 g exhibit high purity,excellent electrochemical performance,high reaction activity,good reversibility,and low polarization level.The discharge capacities are 145,134,117,and 102 m Ah/g at the current densities of 0.1 C,0.2 C,0.5 C and1 C,respectively. This work puts forward a practical suggestion for mass producing environmental benign and low cost Li FeP O4/C as cathode materials of lithium ion batteries.展开更多
Using industrial titanyl sulfate solution as feedstock, titania white pigment was prepared by self-generated seeded thermal hydrolysis method. The influence of some factors (such as F value, volume ratio of pre-adding...Using industrial titanyl sulfate solution as feedstock, titania white pigment was prepared by self-generated seeded thermal hydrolysis method. The influence of some factors (such as F value, volume ratio of pre-adding water to TiOSO4, heating rate and pH of pre-adding water) on the structure and pigment properties of the as-prepared slurry metatitanic acid and titania samples were studied. The samples were characterized by XRD, particle size distribution, SEM and pigment properties test. The results show that all samples show anatase phase, and the calcined samples prepared under suitable conditions are with narrow particle size distribution and good pigment properties. All these influencing factors have great impacts on the hydrolysis velocity, nucleation rate, crystal growth rate, particle size distribution, crystal structure and pigment properties. The suitable F value is 1.73-1.93, the volume ratio of pre-adding water and TiOSO4 solution is 0.28-1, the optimum heating rate is 0.94-1.33 ℃ /min and pH of the pre-adding water should be at near-neutral range.展开更多
基金part of the interdisciplinary SALVE-research project undertaken by the German Archaeological Institute(DAI)in cooperation with the Heidelberg Academy of Sciences and Humanities(HAW)and the University of Tübingen(www.salve-research.org)Project directors are Florian Seiler(DAI)and Michael Märker(HAW)and it was funded by the Deutsche Forschungsgemeinschaft(German Research Foundation).
文摘The AD 79 eruption of Somma-Vesuvius completely buried the ancient landscape around Pompeii (Italy) to some extent conserving the pre-AD 79 Roman paleosols of the Sarno River plain. To estimate potential post-burial soil developments of these paleosols detailed soil liquid and solid phase analysis were carried out. Firstly, an in-situ soil hydrological monitoring was conducted within a pre-AD 79 paleosol in natural undisturbed stratification. The results show that soil water flow and nutrient transport from the overlying volcanic deposits into the pre-AD 79 paleosol take place. Secondly, to estimate their influence on the paleosol’s mineral soil properties, the solid phase of four pre-AD 79 paleosols and associated modern unburied soils were analysed and compared. By combining the data from the soil liquid and solid phase analysis, potential post-burial changes in the paleosols were estimated. Finally, a rise of the mean groundwater table was determined since AD 79. This distinguishes the Sarno River plain into two different zones of post-burial soil developments: 1) lower altitudes where formerly terrestrial paleosols are now influenced by groundwater dynamics and 2) higher altitudes where the paleosols are still part of the vadose zone and rather influenced by infiltration water or interflow. Thus, the mechanism of potential post-burial soil development being active in the pre-AD 79 paleosols is not uniform for the entire Sarno River plain but strongly depends on the paleotopographic situation.
基金supported by the National Science Foundation of China(grant no.21206099)
文摘To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain size of Li FeP O4/C decreases,and the impurities in Li Fe PO4/C composites reduce to a great extent. It makes great sense to the mass industrial production. The optimum synthesis conditions determined in this work are based on the orthogonal experiments. The samples synthesized in a scale of 500 g exhibit high purity,excellent electrochemical performance,high reaction activity,good reversibility,and low polarization level.The discharge capacities are 145,134,117,and 102 m Ah/g at the current densities of 0.1 C,0.2 C,0.5 C and1 C,respectively. This work puts forward a practical suggestion for mass producing environmental benign and low cost Li FeP O4/C as cathode materials of lithium ion batteries.
文摘Using industrial titanyl sulfate solution as feedstock, titania white pigment was prepared by self-generated seeded thermal hydrolysis method. The influence of some factors (such as F value, volume ratio of pre-adding water to TiOSO4, heating rate and pH of pre-adding water) on the structure and pigment properties of the as-prepared slurry metatitanic acid and titania samples were studied. The samples were characterized by XRD, particle size distribution, SEM and pigment properties test. The results show that all samples show anatase phase, and the calcined samples prepared under suitable conditions are with narrow particle size distribution and good pigment properties. All these influencing factors have great impacts on the hydrolysis velocity, nucleation rate, crystal growth rate, particle size distribution, crystal structure and pigment properties. The suitable F value is 1.73-1.93, the volume ratio of pre-adding water and TiOSO4 solution is 0.28-1, the optimum heating rate is 0.94-1.33 ℃ /min and pH of the pre-adding water should be at near-neutral range.