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Abstrak :
Dye-sensitized solar cell (DSSC) is one of the very promising alternative renewable energy sources to anticipate the declination in the fossil fuel reserves in the next few decades and to make use of the abundance of intensive sunlight energy in tropical countries like Indonesia. In the present study, TiO2 nanoparticles of different nanocrystallinity was synthesized via sol− gel process with various water to inorganic precursor ratio (R w) of 0.85, 2.00 and 3.50 upon sol preparation, followed with subsequent drying, conventional annealing and post-hydrothermal treatments. The resulting nanoparticles were integrated into the DSSC prototype and sensitized with an organic dye made of the extract of red onion. The basic performance of the fabricated DSSC has been examined and correlated to the crystallite size and band gap energy of TiO2 nanoparticles. It was found that post-hydrothermally treated TiO2 nanoparticles derived from sol of 2.00 Rw, with the most enhanced nanocrystalline size of 12.46 nm and the lowest band gap energy of 3.48 eV, showed the highest open circuit voltage (Voc) of 69.33 mV.

Abstrak :
The main focus of this article was to investigate the potential of natural zeolite adsorbent for the removal of CO2 and H2S in biogas produced from palm oil mill effluent (POME) in fixed-bed column adsorption. The effects of the flowrates and dosage of the adsorbent on the CO2 adsorption were also studied. The surface area of the adsorbent was determined using the Brunauer, Emmett, and Teller (BET) model, while the pore size distribution was calculated according to the Barrett, Joyner, and Halenda (BJH) model. The morphology of the adsorbent was determined by field emission scanning electron microscopy and energy dispersive x-ray (FESEM-EDX) analysis. Before and after purification, the biogas was analyzed by gas chromatography with a thermal conductivity detector and polydimethylsiloxane as a column. Biogas from the POME, via the anaerobic digestion process, produced 89% CH4 and 11% CO2. The surface and structure of the clinoptilolite zeolites was modified by a strong acid (1M HCl), strong base (1M NaOH), and calcination at 450°C, and the surface area of the natural zeolites was reduced up to 16%. The working capability of CO2 adsorption by the modified zeolites decreased with increasing flow rates (100, 200, and 300 mL/min) of the biogas, with levels of CO2 at 106,906, 112,237, and 115,256 mg/L. The removal of the CO2 in the biogas by using adsorbent dosages of 1.5, 2.0, and 2.5 g was 97,878, 97,404 and 93,855 mg/L, respectively. The optimum purification of the biogas occurred under the flow rate of 100 mL/min and adsorbent dosage of 2.5 g. The high working capability of the modified zeolites for the removal of CO2 in the biogas was a key factor, and the most important characteristic for the adsorbent. The results indicate that clinoptilolite zeolites are promising adsorbent materials for both the purification and upgrading of biogas.

Abstrak :
ABSTRACT
Background: Tadalafil is a PDE5I which has been licensed for the treatment of erectile dysfunction (ED) since 2003, is effective from 30 minutes after administration and its efficacy is maintained for up to 36 hours. More recently, it is also given OAD in a lower dose to allow spontaneous sexual activities. However, whether OAD administration is more effective than PRN administration in improving the EF is yet to be established. This study aimed to evaluate whether OAD administration of tadalafil leads to a better improvement of erectile function (EF) in patients with erectile dysfunction (ED) compared to PRN administration. Methods: literature search of electronic database was performed through Medline, Scopus, Cochrane Library, and CINAHL databases. Cochrane Risk of Bias Tool was then employed to assess the risk of bias in each study. Results: initial literature search resulted in 231 hits, but only four studies were included in final selection. Based on our judgements, the study by Kang et al. was the most applicable in our clinical setting. This study showed that subjects who received tadalafil OAD had statistically significant higher increases of mean IIEF-EF (6,5 (SD 4,5) vs 4,9 (SD 4,2), p=0,032), proportion of yes responses to SEP-2 (81,8% vs 64,7%, p=0,025), and proportion of yes responses to SEP-3 (77,3% vs 60,3%, p= 0,034). Conclusion: administration of tadalafil OAD leads to a better improvement of EF compared to PRN administration.