This study examines the role of the nano- and micro-particle ratio in dispersion stability and mechanical properties of composite resins for SLA(stereolithography) 3D printing technology. VTES(vinyltriethoxysilane)-coated ZrO2 ceramic particles with different nano- and micro-particle ratios are prepared by a hydrolysis and condensation reaction and then dispersed in commercial photopolymer (High-temp) based on interpenetrating networks(IPNs). The coating characteristics of VTES-coated ZrO2 particles are observed by FE-TEM and FT-IR. The rheological properties of VTEScoated ZrO2/High-temp composite solution with different particle ratios are investigated by rheometer, and the dispersion properties of the composite solution are confirmed by relaxation NMR and Turbiscan. The mechanical properties of 3Dprinted objects are measured by a tensile test and nanoindenter. To investigate the aggregation and dispersion properties of VTES-coated ZrO2 ceramic particles with different particle ratios, we observe the cross-sectional images of 3D printed objects using FE-SEM. The 3D printed objects of the composite solution with nano-particles of 80 % demonstrate improved mechanical characteristics.
The purpose of this study is to investigate the optimum conditions of dispersion and strength to maximize the mechanical properties of woody cellulose nano–crystal (CNC). As a dispersing method, ultrasonic dispersing machine and magnetic stirrer were used as the mechanical dispersion method. The mixing ratio of cellulose nano-crystals (CNCs) was 0.2% and the dispersion time was 10 minutes. Steam curing was carried out for 6, 24 and 48 hours. Based on the experimental results, we will propose source technology regarding CNC for construction materials.
Nanosized and aggregated Y2O3:Eu Red phosphors were prepared by template method from metal salt impregnated into crystalline cellulose. The particle size and photoluminescent property of Y2O3:Eu red phosphors were controlled by variation of the calcination temperature and time. Dispersed nanosol was also obtained from the aggregated Y2O3:Eu Red phosphor under bead mill wet process. The dispersion property of the Y2O3:Eu nanosol was optimized by controlling the bead size, bead content ratio and milling time. The median particle size (D50) of Y2O3:Eu nanosol was found to be around 100 nm, and to be below 90 nm after centrifuging. In spite of the low photoluminescent properties of Y2O3:Eu nanosol, it was observed that the photoluminescent property recovered after re-calcination. The dispersion and photoluminescent properties of Y2O3:Eu nanosol were investigated using a particle size analyzer, FE-SEM, and a fluorescence spectrometer.
A bulk porous composite with plantinum nano-dispersion was synthesized in air atmosphere through the combination of several in situ reactions, including the pyrolysis of . A mixture of (dolomite), , and LiF (0.5 wt%, as an additive) was cold isostatically pressed at 200 MPa and sintered at for 2 h. The porous composite ( : Pt=99 : 1 in volume) had a uniformly open-porous structure (porosity: 56%) with three-dimensional (3-D) network and a narrow pore-size distribution, similarly to the porous composites reported before. Catalytic Properties (viz., NO direct decomposition and NO reduction by ) of the composite were investigated up to . In the absence of oxygen, the NO conversion rate reached ~52% for the direct decomposition and ~100% for the reduction by , respectively. The results suggest the possibility of the porous composite as a multifunctional filter, i.e., simultaneous hot gas-filtering and in one component.
Background : Cu ion is an essential mineral of animal feed. But rapid degradation of Cu ion in animal intestine causes poor immune activity and potential environment hazard. Therefore, to enhance immune system and control metal ion deliverly in intestine, we developed Cu ion nano suspension. In animal feed, > 127 ㎎/g of Cu ion are found but only 5 - 7 ㎎ are used out of them. Therefore, huge loss of Cu ion causes environment, economy and animal health problem. Methods and Results : Seven formulation were prepared to prepare nano suspension (particle size < 200 ㎚) of CuSO4. The particle diameter, polydispersity index, and zeta potential values of the samples were measured using dynamic light scattering (DLS) and laser Doppler methods (ELS-Z1000; Otsuka Electronics, Tokyo, Japan). Absorbance and Cu ion concentration was measured using UV-VIS Spectrophotometer. Cu ion nano particle (< 200 ㎚) was found in a formulation comprised of Cu ion : surfactant (lipophilic : hydrophilic) and PEG. In consistence with this result, total absorbance and concentration was found higher in the same formulation compared to control. Conclusion : From our experiment we may conclude that mixture of Cu ion : surfactant (lipophilic : hydrophilic) and PEG successfully prepared nano suspension which slow down the degradation of Cu ion in intestine with improving feed quality, animal health and prevent potential environment pollution.