In an effort to explore the use of natural resources, stoneware ceramics have been made using iron sand as a filler to replace quartz Kalimantan. The results showed that iron sand can be well used in making stoneware ...In an effort to explore the use of natural resources, stoneware ceramics have been made using iron sand as a filler to replace quartz Kalimantan. The results showed that iron sand can be well used in making stoneware ceramics. This is shown by the measurement of water absorption which is less than 5% and has compressive strength slightly smaller compared to stoneware ceramics made with quartz as a filler.展开更多
Investigation of the substitution process can provide a better understanding of the superconducting mechanisms in cuprous oxide materials. In this work the effects of substitution Lanthanum (La) for Gadolinium (Gd) on...Investigation of the substitution process can provide a better understanding of the superconducting mechanisms in cuprous oxide materials. In this work the effects of substitution Lanthanum (La) for Gadolinium (Gd) on the structure and oxygen content for x = 0.0 - 0.5 in the compound Gd1-xLaxBa2Cu3O7-δ (GLBCO-123 phase) have been investigated. Samples were synthesized by using a wet-mixing method from powders of Gd2O2, La2O2, BaO, CuO, and solution of HNO3. Based on the analysis of XRD data and SEM-EDXA, it confirms that the sample has formed the GLBCO-123 phase, as expected. It has been obtained that the lattice parameters a and c are increased while the parameter b is slightly decreased with increasing content of Lanthanum. The oxygen content slightly decreased and structure of the Gd1-xLaxBa2Cu3O7-δ phase changed from orthorhombic to tetragonal with increasing the content of Lanthanum.展开更多
Synthetic membranes have gained an important place in chemical technology and are used in a broad range of applications. UV irradiation is an age old process used for disinfection as well as for sterilization purposes...Synthetic membranes have gained an important place in chemical technology and are used in a broad range of applications. UV irradiation is an age old process used for disinfection as well as for sterilization purposes. It is used for sterilizing equipment in which polysulfone (PSf) membranes are used. As a result, short time UV irradiation of polymer membranes has acquired importance in recent times. In the present study, microporous polysulfone membranes with0.108 mmthickness have been prepared using phase inversion method. Effect of UV irradiation on the membranes for short time intervals (0 - 60 minutes) has been investigated using UV-Vis and FTIR spectrophotometer, and SEM. The performance of the membranes has studied by filtration techniques. UV-Vis and IR spectra analysis and SEM images obtained suggest that chains scission and crosslink have occurred simultaneously in the irradiated membranes by UV radiation in a dose dependant manner. The pure water flux (PWF) values of irradiated membranes obtained from filtration studies were higher compared to that of the control membrane. These results show that a very short UV irradiation (2 minutes) affected the physicochemical characteristics of microporous polysulfone membrane which it increases with increase in time.展开更多
In an effort to improve the performance of superconductors in the field and high temperatures it is important to study the superconducting mechanism. For this reason, the cation substitution can be conducted. One of t...In an effort to improve the performance of superconductors in the field and high temperatures it is important to study the superconducting mechanism. For this reason, the cation substitution can be conducted. One of the high Tc superconductors Gd1Ba2Cu3O7−δ phase with Sr substitution has been synthesized, i.e. Gd1(Ba2−xSrx)Cu3O7−δ compound. The sample was synthesized by using a solid-state reaction method with a wet mixing, sintered for 12 hours at temperature 900°C. The synthesis results are characterized by using XRD. The results of Match-3 software analysis showed high (higher 85%) Gd1Ba2Cu3O7−δ phase was formed. The Sr substitution causes changes to the structure, i.e. the lattice parameters a, b and c, where the orthorhombicity tends to decrease with increasing Sr content. Refinement results show that based on the oxygen occupancy, the total oxygen content tends to increase.展开更多
文摘In an effort to explore the use of natural resources, stoneware ceramics have been made using iron sand as a filler to replace quartz Kalimantan. The results showed that iron sand can be well used in making stoneware ceramics. This is shown by the measurement of water absorption which is less than 5% and has compressive strength slightly smaller compared to stoneware ceramics made with quartz as a filler.
文摘Investigation of the substitution process can provide a better understanding of the superconducting mechanisms in cuprous oxide materials. In this work the effects of substitution Lanthanum (La) for Gadolinium (Gd) on the structure and oxygen content for x = 0.0 - 0.5 in the compound Gd1-xLaxBa2Cu3O7-δ (GLBCO-123 phase) have been investigated. Samples were synthesized by using a wet-mixing method from powders of Gd2O2, La2O2, BaO, CuO, and solution of HNO3. Based on the analysis of XRD data and SEM-EDXA, it confirms that the sample has formed the GLBCO-123 phase, as expected. It has been obtained that the lattice parameters a and c are increased while the parameter b is slightly decreased with increasing content of Lanthanum. The oxygen content slightly decreased and structure of the Gd1-xLaxBa2Cu3O7-δ phase changed from orthorhombic to tetragonal with increasing the content of Lanthanum.
文摘Synthetic membranes have gained an important place in chemical technology and are used in a broad range of applications. UV irradiation is an age old process used for disinfection as well as for sterilization purposes. It is used for sterilizing equipment in which polysulfone (PSf) membranes are used. As a result, short time UV irradiation of polymer membranes has acquired importance in recent times. In the present study, microporous polysulfone membranes with0.108 mmthickness have been prepared using phase inversion method. Effect of UV irradiation on the membranes for short time intervals (0 - 60 minutes) has been investigated using UV-Vis and FTIR spectrophotometer, and SEM. The performance of the membranes has studied by filtration techniques. UV-Vis and IR spectra analysis and SEM images obtained suggest that chains scission and crosslink have occurred simultaneously in the irradiated membranes by UV radiation in a dose dependant manner. The pure water flux (PWF) values of irradiated membranes obtained from filtration studies were higher compared to that of the control membrane. These results show that a very short UV irradiation (2 minutes) affected the physicochemical characteristics of microporous polysulfone membrane which it increases with increase in time.
基金This report is part of the fundamental research report with contract No.486 127/UN14.2/PNL.01.03.00/2016.
文摘In an effort to improve the performance of superconductors in the field and high temperatures it is important to study the superconducting mechanism. For this reason, the cation substitution can be conducted. One of the high Tc superconductors Gd1Ba2Cu3O7−δ phase with Sr substitution has been synthesized, i.e. Gd1(Ba2−xSrx)Cu3O7−δ compound. The sample was synthesized by using a solid-state reaction method with a wet mixing, sintered for 12 hours at temperature 900°C. The synthesis results are characterized by using XRD. The results of Match-3 software analysis showed high (higher 85%) Gd1Ba2Cu3O7−δ phase was formed. The Sr substitution causes changes to the structure, i.e. the lattice parameters a, b and c, where the orthorhombicity tends to decrease with increasing Sr content. Refinement results show that based on the oxygen occupancy, the total oxygen content tends to increase.
