Flotation Separating Rutile from Calcium and Silicon Gangue Minerals

Rutile separation from calcite, apatite and quartz by flotation was investigated. The results show that the rutile separation from calcium and silicon gangue minerals can be realized with alkyl-imino-bismethylene phosphoric acid (TF112) as a collector and sodium hexametaphosphate (SH) as a regulator.

Syntactic Intergrowth Structure in the Calcium-Rare Earth Fluorocarbonate Minerals

The microstructural characteristics of syntactic polycrystal in the calcium rare earth fluorocarbonate minerals from Southwest China have been studied by means of selected area electron diffraction and high resolution electron microscopy(HREM). The complication of the heterogeneous fabric of the minerals have been revealed by HREM. The results show that the crystal structure of the minerals was formed by a disorder stacking of the unit layers of bast naesite and synchisite in the calcium rare earth fluorocarbonate minerals along c direction. The stacking fault and other crystal defects in the syntactic polycrystal have been discussed.

Aragonite from Mulanshan Glaucophane Schist: Implications for Regional Evolution of Southwestern Dabie Mountains, Central China

The aragonite, an index mineral of glaucophane schist facies, has not been confirmed in the Dabie Mountains high pressure and ultrahigh pressure metamorphic belts. The Mulanshan glaucophane schist in Huangpi County, Hubei Province is located in the southwestern Dabie Mountains, Central China. The micron sized intergranular aragonite is confirmed with optical microscope (OM) and electron probe microanalysis (EPMA) in the glaucophane schist. The submicrometer sized ellipse aragonite inclusion is observed by using bright field image (BFI), X ray energy damage spectrograph (EDS) and selected area electron diffraction (SAED) with transmission electron microscope in the quartz lens of glaucophane albite epidote chlorite schist from Mulanshan. The presence of aragonite indicates not only the average geothermal gradient of the Mulanshan glaucophane schist less than 10 ℃/km, which is very close to that of eclogite in the Dabie Mountains metamorphic belts, but also the relatively higher concentration of CO2 during the metamorphic process. In addition, the glaucophane schist free of such index minerals as lawsonite, prehnite and pumpellyite, has been attributed to the effect of CO2 on the stability of calcium aluminum silicate minerals during the low grade metamorphism. EDS and SAED analysis results show that the host of aragonite inclusion is amorphous SiO2. The occurrence of amorphous SiO2 indicates a quick cooling process during the exhumation of the Mulanshan glaucophane schist. These results suggest that the rapid exhumation mechanism of the glaucophane schist, the same as that of eclogite in the Dabie Mountains metamorphic belts, occurred in the geodynamic context of subduction obduction.

Calcium-mineralized polypeptide nanoparticle for intracellular drug delivery in osteosarcoma chemotherapy

The acidic microenvironments of tumor tissue and cells provide an opportunity for the development of pHresponsive drug delivery systems in cancer therapy.In this work,we designed a calcium carbonate(CaCO3)-corecrosslinked nanoparticle of methoxy poly(ethylene glycol)-block-poly(L-glutamic acid)through mineralization for intracellular delivery of doxorubicin(DOX),referred to as CaNP/DOX.CaNP/DOX exhibited high drug loading capability,uniform nanoparticle size,and pH-dependent DOX release.In the meantime,the enhanced cell uptake,superior cytotoxicity toward mouse osteosarcoma K7 cells,extended circulation half-life,and improved accumulation of DOX in K7 allograft tumor from CaNP/DOX were also demonstrated.More interestingly,CaNP/DOX displayed improved antitumor effect and reduced side effects against the K7 osteosarcoma-allografted mouse model and the 143B orthotopic osteosarcoma mouse model.Given the superior properties of Ca-mineralized polypeptide nanoparticle for intracellular drug delivery,the smart drug delivery system showed strong competitiveness in clinical chemotherapy of cancers.