Studies on Colloidal Properties of Mixed Metal Hydroxide－Clay Aqueous Suspension

he electrical property,stability and rheological property of mixed metal hydroxide(MMH)-clay aqueous suspensions were studied via determining elec- trophoretic mobilities,heterocoagulation and rheological parameters. The suspen- sions of MMH-Na-montmorillonite and MMH-Kaolinite may be transformed from negatively charged systems into positively charged systems through changing the ratio of MMH to clav. The increase of MMH content makes the stability of dilute MMH-clay suspensions decreased in negatively chrged systems and increased in positively chrged systems. The complete coagulations at near neutral systems oc- curs. In the concentrated MMH-clay suspension,the steric network structures may be formed between MMH and clay particles,which cause the apparent viscosity(AV)and Bingham yield point(YP) of the suspentqion to increase. There is a suit- able ratio of MMH to clay at which the AV and YP of the suspension attain a maximum value,which in agreement with “bridging theory”of polymer flocculation.

A review of nutriology of food hydrocolloids

Most current commercially important hydrocolloids could be considered as dietary fibers.A great deal of research has focused on the bio-function of hydrocolloid materials resulting from their chemical structure,including antioxidant properties,bacteriostatic capacity and cancer prevention.However,the colloidal properties of hydrocolloids in water-holding,high viscosity,gelling and indigestion,which are characterized by macromolecules,also contribute to the human health.Therefore,the nutritional value of hydrocolloids deriving from their colloid properties is defined as colloid nutriology.More specifically,hydrocolloids in this study refer to dietary fibers which are metabolically inert or fermented in the colon or large intestine.Based on this conception,this mini-review attempts to elaborate the nutritional value of hydrocolloids resulting from its colloidal properties.

Enhancement of adjustable localized surface plasmon resonance in ZnO nanocrystals via a dual doping approach

Recently, the localized surface plasmon resonance （LSPR） concept was expanded from noble metals to doped semiconductor nanocrystals （NCs）. However, the strengthening of the intrinsically very weak LSPR in NCs remains a great challenge for its applications in optics, electronics and optoelectronics fields. In this work, we report on the remarkable strengthening and controllability of LSPR in ZnO through a dual-doping strategy. First, high quality In-doped ZnO （IZO） NCs with intense LSPR were synthesized by a simple single-pot method. Importantly, the LSPR can be tuned by simply adjusting the concentration of In dopant, as well as by UV light irradiation （photo-induced doping）. The pattern of electricity of an IZO NC film matches the shift of LSPR independent of dopant concentration. The UV light irradiation clearly enhanced the electrical properties of the films （350 fl/sq） due to increase carrier density explained by LSPR and confirmed by X-ray photoelectron spectroscopy, The IZO NCs can be easily dispersed in various organic solvents and serve as inks for assembling uniform films via solution processes. These IZO NC ink is promising for application in next-generation solution-based field effect transistors and other optoelec- tronic devices.