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The presence of spacecraft in ionospheric plasma can change plasma properties, vice versa plasma can lead to charge buildup on spacecraft. The level of charging, through electric potential of spacecraft, initially depends on plasma density. However, simulations done on four LEO satellites, i.e. ERS 1, MIDORI, ASCA and FUSE 1, showed that charging level depends on plasma electron temperature rather than plasma density which satisfied the Boltzmann’s relation in the absence of high-energy electrons from aurora. The higher the plasma electron temperature the more spacecraft exposed to negative charging. It is assumed that plasma ions and electrons are collisionless or in Maxwellian distribution. It is found that there is no strong relation between density and charging level. Furthermore, there exists insignificant different of charging between polar and equatorial satellites. It means that the placement of satellite in polar or equatorial region, as long as the presence of auroral electrons is excluded, will suffer similar level of charging which is less than 5V (negative). Since spacecraft are exposed to negative charge, electric field generated by spacecraft potential, together with mesothermal motion effects, deflects ion trajectory into donwstream region leading to ion void region. The ion density is reduced compared to electron density, but there is no significant different of ion void feature between polar and equatorial satellites.and capacity building of beneficiaries.

This paper reports the synthesis, characterization, anticancer screening and quantum chemical calculation of a tetradentate Schiff base 2,2'-((1E,1'E)-((2,2-dimethylpropane-1,3-diyl)bis- (azanylylidene))bis(methanylylidene))bis(4-fluorophenol) (L2F) and its Pd (II) complex (PdL2F). The compounds were characterized via UV-Visible, NMR, IR spectroscopy and single crystal x-ray diffraction. Density Functional Theory (DFT) and time-dependent DFT calculations in gas and solvent phases were carried out using B3LYP, B3P86, CAM-B3LYP and PBE0 hybrid functionals combined with LanL2DZ basis set. Complexation of L2F to form PdL2F was observed to cause a bathochromic shift of the maximum absorption bands of n-π* from 327 to 410 nm; an upfield shift for δ (HC = N) from 8.30 to 7.96 ppm and a decreased wavenumber for ν(C = N) from 1637 to 1616 cm-1. Overall, the UV-Vis, NMR and IR spectral data are relatively well reproduced through DFT and TD-DFT methods. L2F and PdL2F showed IC50 of 90.00 and 4.10 μg/mL, respectively, against human colorectal carcinoma (HCT116) cell lines, signifying increased anticancer activity upon complexation with Pd (II).

Abstract A satellite placed in space is constantly affected by the space environment, resulting in various impacts from temporary faults to permanent failures depending on factors such as satellite orbit, solar and geomagnetic activities, satellite local time, and satellite construction material. Anomaly events commonly occur during periods of high geomagnetic activity that also trigger plasma variation in the low Earth orbit (LEO) environment. In this study, we diagnosed anomalies in LEO satellites using electron data from the Medium Energy Proton and Electron Detector onboard the National Oceanic and Atmospheric Administration (NOAA)-15 satellite. In addition, we analyzed the fluctuation of electron flux in association with geomagnetic disturbances 3 days before and after the anomaly day. We selected 20 LEO anomaly cases registered in the Satellite News Digest database for the years 2000–2008. Satellite local time, an important parameter for anomaly diagnosis, was determined using propagated two-line element data in the SGP4 simplified general perturbation model to calculate the longitude of the ascending node of the satellite through the position and velocity vectors. The results showed that the majority of LEO satellite anomalies are linked to low-energy electron fluxes of 30–100 keV and magnetic perturbations that had a higher correlation coefficient (~ 90%) on the day of the anomaly. The mean local time calculation for the anomaly day with respect to the nighttime migration of energetic electrons revealed that the majority of anomalies (65%) occurred on the night side of Earth during the dusk-to-dawn sector of magnetic local time.

Acid Mine Drainage (AMD) contains Fe(II) and Mn(II) metals, which can cause environmental pollution. This research aimed to investigate the potency of activated carbon made from coal as an adsorbent in AMD treatment. The carbon was made of coal and activated with H3PO4 in a weight ratio of 40%, 800 °C for 120 minutes while supplying 1.5 L/min of nitrogen during the carbonization process. The result shows that BET surface area, total pore volume, and iodine number were 296.4 m2/g, 0.156 cc/g, and 1205 mg/g, respectively. The surface contained many fractures, channels, and big holes, as evidenced by the FT-IR and SEM investigations, and it also had acidic surface functional groups. The optimum contact time adsorption for AMD treatment was 30 minutes, and the first concentration of Fe(II) and Mn(II) metals affected the adsorption. The optimum removal of Fe(II) in AMD treatment was 95.27% at an initial concentration of 3.51 ppm, while the optimum removal of Mn(II) was 99.82% at an initial concentration of 5.71 ppm. This activated carbon has a considerable potency to be used as the adsorbent in AMD treatment to reduce Fe(II) and Mn(II) levels.

The "Socialization of Economic and Islamic Financial Sustainability for Student Entrepreneurs" was a collaborative event between Universitas Syiah Kuala (USK) and Universiti Malaysia Sabah (UMS) on June 25, 2024. It aimed to enhance student entrepreneurs' understanding of Islamic finance and Sharia law. Using the service-learning method, Dr. Dg. Safrina Ag. Budin presented on "Diversification of Islamic Banking Products in Malaysia," and Dr. Ridwan Nurdin discussed "The Uniqueness of Sharia in Aceh." Results showed significant improvement in participants' knowledge and engagement. This activity effectively contributed to promoting sustainable economic and financial practices among student entrepreneurs, aligning with the Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

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Chemical industries are greatly assisted by catalysts; and commonly used catalysts for C-C formation reactions are mainly phosphine-based complexes which are air and moisture sensitive. New air stable Schiff base Pd(II) complexes have been synthesised, characterised and screened for their catalytic potential. This paper reports three ONNO Schiff bases, namely, L2C [2,2'-((l E ,l'E)-((2,2-dimethylpropane-l,3- diyl) bis (azanylylidene)) bis (methanylylidene)-) bis (4-chlorophenol)], L2M [2,2'-((lE ,l'E)-((2,2- dimethylpropane-l,3-diyl)bis(azanylyli-dene)) bis (methanylylidene)) bis (4-methylphenol)] and L2H [2,2'-((lE ,l'E) - ((2,2-dimethyl-propane-l,3-diyl)bis (azanylylidene)) bis (methanylylidene)) diphenol]. These were synthesised from 2,2-dimethyl-l,3-propanediamine and salicylaldehyde derivatives with Cl, CH3 and H at the meta position, respectively. The compounds were reacted with palladium(II) acetate yielding three palladium(II) complexes denoted as PdL2C, PdL2M and PdL2H. The structures of all compounds were elucidated through elemental analysis, 1H and 13C NMR, FTIR and melting point. The complexes were screened for catalytic activities in Sonogashira coupling reaction between iodobenzene and phenylacetylene in DMSO. PdL2H was found to be the most active catalyst with 87% iodobenzene conversion after 12 hours of reaction. [ABSTRACT FROM AUTHOR]

This study examined the profitability of technical analysis using moving-average (MA) crossover strategy compared with the conventional simple buy-and-hold strategy, using Malaysian equity market. We investigates the performance of the original moving-average strategy and a modified moving-average crossover strategy with additional trading rules such as entry rule, exit rule, holding rule, and stop-loss rule. The results are consistent to previous studies that strongly support moving-average crossover trading strategies. The result suggests that all combinations of short-MA and long-MA periods of the original MA crossover strategy and majority combinations of short-MA and long-MA of the modified MA crossover strategy outperform market benchmark with higher risk-adjusted return. In addition, the 1-period short-MA demonstrates the best return in both original and modified moving-average crossover strategy; better still the modified strategy outperforms the original strategy with lower frequency of trades which could largely reduce transaction costs and with lower return distribution variability.