Papers by Keyword: Na

Abstract: Nanoparticle has been used in agricultural practices such as soil ameliorant. Nanoparticle of volcanic ash and biofertilizer were applied to improve some soil characteristics of Inceptisols. The objective of this research was to optimize the benefit of nanoparticle of volcanic ash and biofertilizer in reducing soil acidity, increasing organic carbon content, and increasing basic cations of Inceptisols. Volcanic ash was obtained from the eruption of Mt. Merapi in Central Java. Nanoparticle was grinded in Nanotechnology and Graphene Research Center, Universitas Padjadjaran. Phosphate solubilizing fungi was used as biofertilizer, isolated in Soil Microbiology Laboratory, Universitas Padjadjaran. A two factors randomized experimental design was used in this research. Nanoparticle of volcanic ash was used as first factor (four levels: 0%, 2%, 4% and 6% of soil weight percentages). Biofertilizer was used as second factor (two levels: 0 and 10 g.kg^-1). These two treatments were combined and mixed evenly and incubated for three months in field condition. Every month during those three months a few soil samples were taken to analyze the change of soil characteristics. The results showed that the treatments increased organic carbon content and potassium basic cation but had no effect to soil acidity.

Abstract: The first-principles with pseudopotentials method based on the density functional theory was applied to calculate the formation energy of impurities and the electronic structure of ZnO doped with Na. In Na-doped ZnO, Na_O is the most unstable than the other cases. Simultaneously, Na_Zn is more stable than Na_i according to that Na_Zn have smaller formation energy. Furthermore, the electronic structure of Na-doped ZnO indicates that that Na_Zn behaves as an acceptor, while Na_i behaves as a donor.

Abstract: In this paper, we designed a new type of high precision 1 μA constant current source after deeply studying the high precision precise dc constant current source. Compared with the traditional constant current source, in this paper we adopted complex amplifier added with floating power supply outside to design high precision dc constant current source which is for China's space use , its output current is 1 μA, resolution is 0.1 nA, accuracy is 0.5. This high precise dc constant current source is mainly used for new model rocket engine performance testing in aerospace, but also can be widely applied in different fields in need of precision measurement.

Abstract: A series of coke samples with loading alkali and alkaline earth metals were prepared by the impregnation method, the NOx emission were investigated in a silica fixed bed reactor in the combustion process of raw coke and coke modified by Na, K, Ca and Mg. The results show that Na, K, Ca and Mg play in-situ catalytic effects on the NOx reduction reactions. When the loading amount of Na2CO3 is 2.0%, the NOx reduction ratio was around 17.4%, when the loading of K2CO3 is 2.0%, the amount of NOx emission is reduced by 26.5%. When the loading of CaCl2 is 2.0%, the amount of NOx emission is reduced by 22.3%. When the loading of MgCl2 is 2.0%, the NOx reduction ratio is about 10.9%.

Abstract: The article chooses Na, LiPb and LBE three kinds of metal coolant, and makes a comparative analysis of the thermophysical properties of Na, LiPb and LBE when they are at liquid state. The results show that Na has the lowest density and the largest thermal conductivity and specific heat capacity. There is a small difference between LBE and LiPb in terms of density, thermal conductivity and specific heat capacity. LiPb has the largest kinematic viscosity. The thermal conductivity of Na decreases as temperature rises, which is opposite of LBE and LiPb. The kinematic viscosity of LiPb increases as temperature rises. Considering thermal conductivity and specific heat capacity, LBE and LiPb are not the best coolant. However, their high densities can economize equipments and materials at the same time. When it flows, LiPb’s heat transfer capacity gets larger as temperature rises, this character can not be ignored in fusion reactor.