No abstract

The purpose of this research is to create a model of the discharge as the impact of climate change due to global warming. The study was conducted using data from the Bangga watershed. Monthly water balance model used is the development of a model FJ. Mock by entering the natural phenomena that occur at this time such as climate change, canopy interception, rainfall distribution based on land use, soil type and soil characteristics. Calibration of water balance is used to determine the performance of the models to variations in climate change. Then, analysis is conducted as the effect of rain and temperature on runoff at river Bangga. The conclusion of this research were: 1) Accuracy of discharge simulation models against observed discharge is quite good, which is characterized by the Nash coefficient (Ns) close to one except for a few periods and annual rainfall runoff ratio (RE) approaches one. 2) Changes in rainfall have a considerable influence on the runoff, while the effect of temperature on runoff is not too significant.

MgO nanoparticle was synthesized by sol-gel method from magnesium acetate and oxalic acid dissolved in methanol followed by annealed process. Characterization of functional groups was performed using (FTIR) Fourier Transforms Infrared spectroscopy, crystal profile analysis using (XRD) X-ray Diffraction and morphology using (SEM) Scanning Electron Microscopy. The FTIR and XRD results indicated that the magnesium acetate converted into magnesium oxalate (Precursor), and then the anneal process was changed into MgO nanoparticles. The Scherrer's equation used to determine the distribution of MgO nanoparticle crystals. Modified Williamson-Hall plot is used to determine the strain, stress and energy density value (micro structural properties) based on angle values 2θ and (FWHM) Full width at half maximum of XRD angles from 10° to 80°. The results of the XRD and SEM analysis show that magnesium complexes have changed. The solid layer formed by the Mg polymer complex network is transformed into a cubic structure.

No abstract

Quantitative Structure and Activity Relationship (QSAR) analysis of 13 benzothiazoles derivatives compound as antimalarial compounds have been performed using electronic descriptor of the atomic net charges (q), dipole moment (μ), ELUMO, EHOMO and polarizability (α). The electronic structures as descriptors were calculated through HyperChem for Windows 7.0 using AM1 semi-empirical method. The descriptors were obtained through molecules modeling to get the most stable structure after geometry optimization step. The antimalarial activity (IC50) were taken from literature. The best model of QSAR model was determined by multiple linear regression approach and giving equation of QSAR: Log IC50 = 23.527 + 4.024 (qC4) + 273.416 (qC5) + 141.663 (qC6) – 0.567 (ELUMO) – 3.878 (EHOMO)– 2.096 (α). The equation was significant on the 95% level with statistical parameters: n = 13, r = 0.994, r2 = 0.987, SE = 0.094, Fcalc/Ftable = 11.212, and gave the PRESS = 0.348. Its means that there were only a relatively few deviations between the experimental and theoretical data of antimalarial activity.