A typical amphiphilic star polymer adamantane-[poly(lactic-co-glycolic acid)-bis(2-carboxyethyl) sulfide-poly(ethylene glycol) monomethyl ether)]4 with a specific hydrophilic/redox-sensitive/hydrophobic structure was designed and synthesized through ring opening and esterification reactions. The self-assembled nanomicelles were used as doxorubicin (DOX) delivery vehicles with suitable critical micelle concentrations (5.0 mg/L). After the drug being loaded, drug-loaded micelles showed good drug-loading efficiency (10.39%), encapsulation efficiency (58.1%), and drug release (up to 60%) under simulated biological environment conditions. In addition, the backbone structure of the biodegradable polymer was easily hydrolyzed by the action of biological enzymes. As expected, cell-based studies showed that the designed polymer micelles possessed good biocompatibility (a survival rate of 85% for NH-3T3 cells). Moreover, the drug (DOX) still maintained good anti-cancer effects after being loaded, which caused 40% of MCF-7 cells to survive. These redox-sensitive micelles showed anti-tumor therapeutic potential.

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Gelatinized starch paste was prepared by gelatinizing rice starch at 95°C in a water bath. Then, the rice starch (both normal rice starch and waxy rice starch) paste was subjected to high-pressure homogenization at homogenizing pressure of 20, 40, 60, 80 MPa. The rheological properties (including shear stress versus shear rate, apparent viscosity versus shear rate and thixotropy) of starch paste were studied. The high-pressure homogenization was able to improve the flow properties of starch paste. The shear stress increased with the increasing shear rate, and the Power law equation was capable of fitting the shear stress versus shear rate quite precisely. High-pressure homogenization treatment sharply decreased the thixotropy of starch paste, and the thixotropy of rice starch (both NRS and WRS) paste decreased with the increasing homogenous pressure. Efectos de la homogeneización a alta presión sobre las propiedades reológicas del almidón de arroz RESUMEN Para el presente estudio se preparó pasta de almidón gelatinizada, gelatinizando almidón de arroz a 95ºC en un baño de agua. Luego, la pasta de almidón de arroz (tanto de almidón de arroz normal (NRS) como de almidón de arroz ceroso (WRS)) fue sometida a homogeneización a alta presión, utilizando una presión de homogeneización de 20, 40, 60, 80 MPa. Posteriormente, se estudiaron sus propiedades reológicas (incluida la tensión de corte versus la velocidad de corte, la viscosidad aparente versus la velocidad de corte y la tixotropía). La homogeneización a alta presión mejoró las propiedades de flujo de la pasta de almidón. El esfuerzo cortante aumentó con el incremento de la velocidad de corte, y la ecuación de la ley de potencia fue capaz de ajustar la tensión de corte versus la velocidad de corte con bastante precisión. El tratamiento con homogeneización a alta presión disminuyó drásticamente la tixotropía de la pasta de almidón; además, la tixotropía de la pasta de almidón de arroz (tanto NRS como WRS) disminuyó con el aumento de la presión homogénea.

Use polyurethane rubber composite modified asphalt.Through the Marshall test and rutting test, test of polyurethane rubber asphalt mixture high temperature stability, low temperature crack resistance and water damage resistance, verify the composite modification advantages.