We studied the particle growth in a protoplanetary disk in a high-ionization environment and found that icy planet formation is inactive for a disk with an ionization rate 100 times higher than that of the present Sol...We studied the particle growth in a protoplanetary disk in a high-ionization environment and found that icy planet formation is inactive for a disk with an ionization rate 100 times higher than that of the present Solar System. In particular, in the case of M < 10^(-7.4)M_☉yr^(-1), only rocky planet formation occurs. In such a case, all the solid materials in the disk drift inward, eventually reach the inner MRI front,and accumulate there. They form a dense, thin sub-disk of solid particles, which undergoes gravitational instability to form rocky planetesimals. The planetesimals rapidly grow into a planet through pebble accretion. Consequently, rocky planets tend to be much larger than planets formed through other regimes(tandem planet formation regime and dispersed planet formation regime), in which icy planet formation actively takes place. These rocky planets may evolve into hot Jupiters if they grow fast enough to the critical core mass of the runaway gas accretion before the dispersal of the disk gas, or they may evolve into super-Earths if the gas dispersed sufficiently early.展开更多
The properties of the new solid supper acid catlyst which was immerged by S2O82-and added with Sm2O3 were Studied.And the effect of acid strength,sulfur content and stability on the catalyst S2O82-/ZrO2-SiO2-Sm2O2 cau...The properties of the new solid supper acid catlyst which was immerged by S2O82-and added with Sm2O3 were Studied.And the effect of acid strength,sulfur content and stability on the catalyst S2O82-/ZrO2-SiO2-Sm2O2 caused by the dinnovation was studied.展开更多
The synthesis of butyl heptanoate with n butanol and heptanoic acid as reactants and the rare earth solid super acid SO 2- 4/TiO 2/La 3+ as catalyst had been sutdied.The effects of various actors on the reaction were ...The synthesis of butyl heptanoate with n butanol and heptanoic acid as reactants and the rare earth solid super acid SO 2- 4/TiO 2/La 3+ as catalyst had been sutdied.The effects of various actors on the reaction were investigated.The results showed that the appropriate conditions should be:Weight of catalyst is 0.5g(weight of heptanoic acid is 0.2mol);molar ratio of n butanol to heptanoic acid was 1.8∶1;reaction time was 2.0h;dehydrating agent (Toluene) being 15ml.The yield of butyl heptanoate was about 99.2%.展开更多
基金partly supported by Grant-in-Aid for Scientific Research on Innovative Areas Number 26106006
文摘We studied the particle growth in a protoplanetary disk in a high-ionization environment and found that icy planet formation is inactive for a disk with an ionization rate 100 times higher than that of the present Solar System. In particular, in the case of M < 10^(-7.4)M_☉yr^(-1), only rocky planet formation occurs. In such a case, all the solid materials in the disk drift inward, eventually reach the inner MRI front,and accumulate there. They form a dense, thin sub-disk of solid particles, which undergoes gravitational instability to form rocky planetesimals. The planetesimals rapidly grow into a planet through pebble accretion. Consequently, rocky planets tend to be much larger than planets formed through other regimes(tandem planet formation regime and dispersed planet formation regime), in which icy planet formation actively takes place. These rocky planets may evolve into hot Jupiters if they grow fast enough to the critical core mass of the runaway gas accretion before the dispersal of the disk gas, or they may evolve into super-Earths if the gas dispersed sufficiently early.
文摘The properties of the new solid supper acid catlyst which was immerged by S2O82-and added with Sm2O3 were Studied.And the effect of acid strength,sulfur content and stability on the catalyst S2O82-/ZrO2-SiO2-Sm2O2 caused by the dinnovation was studied.
文摘The synthesis of butyl heptanoate with n butanol and heptanoic acid as reactants and the rare earth solid super acid SO 2- 4/TiO 2/La 3+ as catalyst had been sutdied.The effects of various actors on the reaction were investigated.The results showed that the appropriate conditions should be:Weight of catalyst is 0.5g(weight of heptanoic acid is 0.2mol);molar ratio of n butanol to heptanoic acid was 1.8∶1;reaction time was 2.0h;dehydrating agent (Toluene) being 15ml.The yield of butyl heptanoate was about 99.2%.
