The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid(SPA) was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based part...The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid(SPA) was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based particle size analysis, adsorption measurements and DLVO theory. The flotation tests indicated that rutile fines could be flocculated by SPA, and pH, shear force(stirring speed) and stirring time played significant roles in flocculation. The isoelectric point(IEP) and zeta-potential in whole range all moved to negative values as SPA was added according to the results from zeta-potential measurement. It was demonstrated that the primary reason for above was chemical adsorption. The laser-based particle size results showed the particle size at a stirring speed of 1800 r/min and 1000 mg/L SPA was the largest in all experiments. Furthermore, using the optical microscope observation and flotation tests, it was important for flotation of rutile fines to produce the flocculant. In the light of above-mentioned facts, floc flotation of rutile fines could be induced in the form of chemical adsorption by SPA to increase particle size. The data calculated from DLVO theory also indicated that chemical adsorption was the main reason for the formation of flocculant.展开更多
The phase transformation of chalcopyrite and the effect of its phase status on bacterial leaching were studied. Under the protection of high-purity argon, different temperatures(203, 382 and 552℃) were applied to nat...The phase transformation of chalcopyrite and the effect of its phase status on bacterial leaching were studied. Under the protection of high-purity argon, different temperatures(203, 382 and 552℃) were applied to natural chalcopyrite to complete the phase change. In addition, the chalcopyrite was bioleached before and after the phase change. The results show that the chalcopyrite heated at 203 and 382℃ remained in the α phase, whereas the chalcopyrite changed from α to β phase at 552℃. The leaching rates of chalcopyrite after the phase transitions at 203, 382 and 552℃ were 32.9%, 40.5% and 60.95%, respectively. Further, the crystal lattice parameters of chalcopyrite increased and lattice energy decreased, which were the fundamental reasons for the significant increase in leaching rate. Electrochemical experiments demonstrated that with increasing annealing temperature, the polarization resistance decreased and corrosion current density increased. The higher the oxidation rate was, the higher the leaching rate was.展开更多
Self-Incompatibility (SI) Is a genetic mechanism of self/non-self pollen recognition to prevent self-fertilization In many flowering plants and, In most cases, this is controlled by a multl-allellc S-locus. S-RNase ...Self-Incompatibility (SI) Is a genetic mechanism of self/non-self pollen recognition to prevent self-fertilization In many flowering plants and, In most cases, this is controlled by a multl-allellc S-locus. S-RNase and Slocus F box (SLF) proteins have been shown to be the female and male determinants of gametophytlc selfIncompatibility (GSI), respectively, In the Solanaceae, Scrophulariaceae and Rosaceae. Nevertheless, It is thought that additional factors are required for the SI response. Herein, we constructed a mature anther cDNA library from a self-Incompatible Petunia hybrida Vllm. line of the S3S3 haplotype. Using AhS2-RNase from Antirrhinum hispanicum as a bait for yeast two-hybrid screening, we found that petunia germinating pollen (PGP) S/D3 was capable of Interacting physically with the bait. However, the Interaction lacked haplotype specificity. The PGPS/D3 gene Is a single copy gene that Is expressed In tissues such as the style, ovary, pollen, and leaf. The PGPS/D3::GFP (green fluorescence protein) construct was detected In both the membrane and cytoplasm. The Implications of these findings In the operation of S-RNase-based SI are discussed.展开更多
基金Projects(51474254,51774332,51320105006) supported by the National Natural Science Foundation of ChinaProject(NCET-13-0595) supported by the Program for New Century Excellent Talents in University,ChinaProjects(2017zzts579,2017zzts379) supported by the Fundamental Research Funds for the Central Universities of China
文摘The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid(SPA) was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based particle size analysis, adsorption measurements and DLVO theory. The flotation tests indicated that rutile fines could be flocculated by SPA, and pH, shear force(stirring speed) and stirring time played significant roles in flocculation. The isoelectric point(IEP) and zeta-potential in whole range all moved to negative values as SPA was added according to the results from zeta-potential measurement. It was demonstrated that the primary reason for above was chemical adsorption. The laser-based particle size results showed the particle size at a stirring speed of 1800 r/min and 1000 mg/L SPA was the largest in all experiments. Furthermore, using the optical microscope observation and flotation tests, it was important for flotation of rutile fines to produce the flocculant. In the light of above-mentioned facts, floc flotation of rutile fines could be induced in the form of chemical adsorption by SPA to increase particle size. The data calculated from DLVO theory also indicated that chemical adsorption was the main reason for the formation of flocculant.
基金Project(2018zzts768) supported by the Fundamental Research Funds for the Central South University,ChinaProject(51204207) supported by the National Natural Science Foundation of China
文摘The phase transformation of chalcopyrite and the effect of its phase status on bacterial leaching were studied. Under the protection of high-purity argon, different temperatures(203, 382 and 552℃) were applied to natural chalcopyrite to complete the phase change. In addition, the chalcopyrite was bioleached before and after the phase change. The results show that the chalcopyrite heated at 203 and 382℃ remained in the α phase, whereas the chalcopyrite changed from α to β phase at 552℃. The leaching rates of chalcopyrite after the phase transitions at 203, 382 and 552℃ were 32.9%, 40.5% and 60.95%, respectively. Further, the crystal lattice parameters of chalcopyrite increased and lattice energy decreased, which were the fundamental reasons for the significant increase in leaching rate. Electrochemical experiments demonstrated that with increasing annealing temperature, the polarization resistance decreased and corrosion current density increased. The higher the oxidation rate was, the higher the leaching rate was.
基金Supported by the Chinese Academy of Sciences and the National Natural Science Foundation of China (30221002).Acknowledgements The authors are grateful to Qi Xie (Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences) for help with the construction of the cDNA library and the yeast two-hybrid techniques and Tim Robbins for providing P. hybrida. The authors also thank Jiayang Li (Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences) for the pB1221-35S:GFP vector.
文摘Self-Incompatibility (SI) Is a genetic mechanism of self/non-self pollen recognition to prevent self-fertilization In many flowering plants and, In most cases, this is controlled by a multl-allellc S-locus. S-RNase and Slocus F box (SLF) proteins have been shown to be the female and male determinants of gametophytlc selfIncompatibility (GSI), respectively, In the Solanaceae, Scrophulariaceae and Rosaceae. Nevertheless, It is thought that additional factors are required for the SI response. Herein, we constructed a mature anther cDNA library from a self-Incompatible Petunia hybrida Vllm. line of the S3S3 haplotype. Using AhS2-RNase from Antirrhinum hispanicum as a bait for yeast two-hybrid screening, we found that petunia germinating pollen (PGP) S/D3 was capable of Interacting physically with the bait. However, the Interaction lacked haplotype specificity. The PGPS/D3 gene Is a single copy gene that Is expressed In tissues such as the style, ovary, pollen, and leaf. The PGPS/D3::GFP (green fluorescence protein) construct was detected In both the membrane and cytoplasm. The Implications of these findings In the operation of S-RNase-based SI are discussed.