Controllable Synthesis of Polyhedral Fe3O4 Hollow Spheres Using Hexamethylenetetramine as Structure-Directing Agent.

Polyhedral Fe3O4 hollow spheres were synthesized using hexamethylenetetramine as structure-directing agent and the effect of hexamethylenetetramine on the morphology was investigated in detailed. The comparison for samples prepared with and without hexamethylenetetramine indicated that hexamethylenetetramine played a vital role in the formation process of the hollow polyhedral structure. The formation process and growth mechanism of Fe3O4 spheres with hollow polyhedral morphology were preliminarily explored according to a detailed time-dependent morphology and structure evolution. It was deduced that the hollow polyhedral structure can be ascribed to the cooperation of oriented aggregation and Ostwald ripening mechanisms. The as-prepared Fe3O4 hollow spheres with polyhedral structures which possess high magnetization saturation value (73 emu/g) at room temperature, large cavity and huge specific surface area (57.12 m2·g­1) are expected to have wide potential applications, for example in the drug delivery process, magnetic separation and waste treatment in the future.

Hospitalization expenses of coronary heart disease inpatients in China: evidence from two hospitals in Ningxia Hui autonomous region.

Aim: The increasing morbidity from coronary health disease (CHD) has imposed a significant social and economic burden in China. We analyzed the factors affecting hospitalization expenses of CHD patients. Design: From 2012 to 2018, data on 16,726 CHD patients were collected from the hospital information system in Ningxia Hui Autonomous Region. Methods: A multiple ordered logistic regression model was used to analyze the factors affecting hospitalization expenses. Results: The average hospitalization expense was RMB30998.26 ± 29890.03. Hospital materials expenses accounted for roughly 60% of total hospitalization costs. The older adult, patients who were male, in critical health status, with longer hospital stays, unemployed, using antibiotics and undergoing an operation without incision had significantly raised hospital expenses, while those with fewer complications, no operations and self-paying for health care had reduced hospitalization costs (p < 0.05). The length of hospital stay played a partial mediator role (p < 0.05). Public contribution: Controlling the increase of medical materials costs and preventing over-consumption of hospital services by insured patients are recommended.