Zirconia toughened alumina (ZTA) ceramics are very promising materials for structural and biomedical applications due to their high hardness, fracture toughness, strength, corrosion and abrasion resistance and excelle...Zirconia toughened alumina (ZTA) ceramics are very promising materials for structural and biomedical applications due to their high hardness, fracture toughness, strength, corrosion and abrasion resistance and excellent biocompatibility. The effect of unstabilized ZrO<sub>2</sub> on the density, fracture toughness, microhardness, flexural strength and microstructure of some Zirconia-toughened alumina (ZTA) samples was investigated in this work. The volume percentage of unstabilized ZrO<sub>2</sub> was varied from 0% - 20% whereas sintering time and sintering temperature were kept constant at 2 hours and 1580°C. The samples were fabricated from nanometer-sized (<em>α</em>-Al<sub>2</sub>O<sub>3</sub>: 150 nm, monoclinic ZrO<sub>2</sub>: 30 - 60 nm) powder raw materials by the conventional mechanical mixing process. Using a small amount of sintering aid (0.2 wt% MgO) almost 99.2% of theoretical density, 8.54 MPam<sup>?</sup> fracture toughness, 17.35 GPa Vickers microhardness and 495.67 MPa flexural strength were found. It was observed that the maximum flexural strength and fracture toughness was obtained for 10 vol% monoclinic ZrO<sub>2</sub> but maximum Vickers microhardness was achieved for 5 vol% ZrO<sub>2</sub> although the maximum density was found for 20 vol% ZrO<sub>2</sub>. It is assumed that this was happened due to addition of denser component, phase transformation of monoclinic ZrO<sub>2</sub> and the changes of grain size of α-Al<sub>2</sub>O<sub>3</sub> and ZrO<sub>2</sub>.展开更多
Currently, communication system requires multiband small antennas for 5G mobile applications. Driven this motivation, this paper proposes a multiband patch antenna for Wi-Fi, WiMAX and 5G applications. The proposed an...Currently, communication system requires multiband small antennas for 5G mobile applications. Driven this motivation, this paper proposes a multiband patch antenna for Wi-Fi, WiMAX and 5G applications. The proposed antenna can effectively operate at 2.4 GHz as Wi-Fi, 7.8 GHz as WiMAX and 33.5 GHz as 5G communication purposes. The proposed antenna arrays have given directional radiation patterns, very small voltage standing wave ratio, high gain (VSWR) and directivity for each aforementioned systems operating frequency. This antenna is made for multiband purpose which can be effective for not only Wi-Fi and WiMAX but also 5G applications.展开更多
The acceptability and physicochemical qualities of carambola candy were evaluated in order to increase fruit consumption. The goal of this investigation was to see whether there were any techniques to preserve ca...The acceptability and physicochemical qualities of carambola candy were evaluated in order to increase fruit consumption. The goal of this investigation was to see whether there were any techniques to preserve carambola in the form of candy. Sugar in various forms (white sugar, corn syrup, icing sugar, and molasses) was employed in candy making process in this study. Moisture, protein, fat, ash, vitamin C, total sugar content, organoleptic quality and microbial status of the prepared candy were analyzed. Protein, fat, vit-C, and total sugar content of carrambola candy were found to be higher with white sugar solution but moisture and ash content was found to be higher with molasses. On the microbiological analysis, total fungal growth was tested visually at 0 to 90 days and compared with refrigeration and room temperature. Fungal growth was found at 90 days at room temperature for all types of carambola candy. Sensory attributes revealed that sample 2 (corn syrup-based candy) was most delicious and appreciated among other samples. The best characteristic of carambola candy was found with white sugar solution, with sufficient nutrient and lowest fungal growth than candy prepared with corn syrup, icing sugar solution and molasses.展开更多
文摘Zirconia toughened alumina (ZTA) ceramics are very promising materials for structural and biomedical applications due to their high hardness, fracture toughness, strength, corrosion and abrasion resistance and excellent biocompatibility. The effect of unstabilized ZrO<sub>2</sub> on the density, fracture toughness, microhardness, flexural strength and microstructure of some Zirconia-toughened alumina (ZTA) samples was investigated in this work. The volume percentage of unstabilized ZrO<sub>2</sub> was varied from 0% - 20% whereas sintering time and sintering temperature were kept constant at 2 hours and 1580°C. The samples were fabricated from nanometer-sized (<em>α</em>-Al<sub>2</sub>O<sub>3</sub>: 150 nm, monoclinic ZrO<sub>2</sub>: 30 - 60 nm) powder raw materials by the conventional mechanical mixing process. Using a small amount of sintering aid (0.2 wt% MgO) almost 99.2% of theoretical density, 8.54 MPam<sup>?</sup> fracture toughness, 17.35 GPa Vickers microhardness and 495.67 MPa flexural strength were found. It was observed that the maximum flexural strength and fracture toughness was obtained for 10 vol% monoclinic ZrO<sub>2</sub> but maximum Vickers microhardness was achieved for 5 vol% ZrO<sub>2</sub> although the maximum density was found for 20 vol% ZrO<sub>2</sub>. It is assumed that this was happened due to addition of denser component, phase transformation of monoclinic ZrO<sub>2</sub> and the changes of grain size of α-Al<sub>2</sub>O<sub>3</sub> and ZrO<sub>2</sub>.
文摘Currently, communication system requires multiband small antennas for 5G mobile applications. Driven this motivation, this paper proposes a multiband patch antenna for Wi-Fi, WiMAX and 5G applications. The proposed antenna can effectively operate at 2.4 GHz as Wi-Fi, 7.8 GHz as WiMAX and 33.5 GHz as 5G communication purposes. The proposed antenna arrays have given directional radiation patterns, very small voltage standing wave ratio, high gain (VSWR) and directivity for each aforementioned systems operating frequency. This antenna is made for multiband purpose which can be effective for not only Wi-Fi and WiMAX but also 5G applications.
文摘The acceptability and physicochemical qualities of carambola candy were evaluated in order to increase fruit consumption. The goal of this investigation was to see whether there were any techniques to preserve carambola in the form of candy. Sugar in various forms (white sugar, corn syrup, icing sugar, and molasses) was employed in candy making process in this study. Moisture, protein, fat, ash, vitamin C, total sugar content, organoleptic quality and microbial status of the prepared candy were analyzed. Protein, fat, vit-C, and total sugar content of carrambola candy were found to be higher with white sugar solution but moisture and ash content was found to be higher with molasses. On the microbiological analysis, total fungal growth was tested visually at 0 to 90 days and compared with refrigeration and room temperature. Fungal growth was found at 90 days at room temperature for all types of carambola candy. Sensory attributes revealed that sample 2 (corn syrup-based candy) was most delicious and appreciated among other samples. The best characteristic of carambola candy was found with white sugar solution, with sufficient nutrient and lowest fungal growth than candy prepared with corn syrup, icing sugar solution and molasses.
