Mesoporous TiO 2 material was synthesized from dissolution ilmenite as well as from titanium chloride precursor via a sol-gel process in acidic aqueous solution. The properties of these materials were characterized with several analytical techniques including scanning electron microscopy (SEM), transmission electron microscopy (TEM), wide angle X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, and Barrett-Joyner-Halenda (BJH) analysis. The mesoporous TiO 2 materials calcinated at various temperatures were found to have high value surface areas. The photovoltaic of photo-anode build from the mesoporous TiO 2 was characterized with I-V Keitley Multimeter, and it was found that photovoltaics fabricated using the mesoporous TiO 2 have a good performance. Such a high photovoltaic activity is explained with large surface area and small crystal size.

<p>Modification of materials and thicknesses reflector RPB of Kartini reactor has been done to support cancer therapy with BNCT method. Modifications have been investigated by computer simulation method based on software MCNP5. Neutron beam for BNCT must be fulfill the criteria recommended by International Atomic Energy Agency (IAEA), two of which are  n.cm^-2.s^-1 and  . Before the modification of the neutron beam done, the measurements in the end of the RPB indicate that  n.cm^-2.s^-1 and  . These conditions were not fulfilling the requirements of the IAEA, so that the modification of the reflector material and thickness layer of RPB should be done. Those modifications were done by varying the materials PbF2, Pb-nat, 209Bi, Ni-nat (95%) and Fe-nat. The simulation result showed if the material Ni-nat (95%) on the thickness 1.5 cm was use as a coating material reflector optimally. The results after the modification showed that  increased 7,54% with the increase amounted to n.cm^-2.s^-1.  decrease 21,45%, then decreasing the value of       became 1,70.  After the modification the results has not yet fulfill the criteria of the IAEA. Because of the reflector was not the only guide neutron beam. Moderator and filter have not been optimized to deliver results for files that match the criteria of the IAEA for BNCT. Therefore, in future studies modified with the addition of a neutron moderator and also filter is expected to help increasing the quantity of  and decreasing of .</p>

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<span>Synthesis of <span><em>titanium dioxide </em><span>(TiO<span>2<span>) for dye sensitized solar cell (DSSC) with anthocyanins <span>rosella (<span><em>Hibisccus Sabdariffa</em><span>) has succesfully been done using sol-gel technique. The <span>semiconductor layer is a very important part of the DSSC since it gives a high surface area for <span>dye absorption which gives rise to high currents. DSSC was formed structually two electrodes <span>sandwiching the electrolyte. The working electrode is TiO<span>2 <span>layer coating on a Fluorine doped <span>Tin Oxide (FTO) glass substrat and sensitified with anthocyanin dye. A counter electrode is <span>carbon coating on the FTO. The fabricated solar cells have an area of 1.5 cm<span>2<span>, soaked in the <span>anthocyanin dye for 24 hours and 48 hours. The sample was characteriz with X-ray diffraction <span>method. The X-ray diffractogram indicates that the sample possesses rutile and anatase phase. <span>The dye absorption measured using spektrofotometer UV-Visible Lambda 25 showed the<br /><span>absorption occurs in the range 440-620 nm. The efficiencies of the solar cells measured by I-V <span>meter Keithley for 24 and 48 hours soaking are 0.0064(6)%, and 0.0151(4)%, respectively.</span></span></span></span></span></span></span></span></span></span></span><br /></span></span></span></span></span></span></span></span></span></span></span>

The molten salt reactor (MSR) is a generation IV reactor with liquid fuel having nearly zero excess reactivity. Due to the very low excess reactivity, it requires a small number of control rods worth to shut down the reactor. However, as it operates at high temperatures, the core reactivity increases as the fuel temperature cools down during shutdown. In such a case, the control rods might not be able to keep the reactor at a subcritical state, and consequently, the fuel must be removed from the core for long-term shutdown into a fuel drain tank (FDT) below the core. This paper is intended to assess the shutdown capability of the first active shutdown system and fuel drain tank of ThorCon MSR by doing neutronic calculations with MCNP6. The results indicated that the control rods having reactivity worth -1.699 %dk/k are unable to maintain the core at a subcritical state as the core excess reactivity increases to +7.760 %dk/k when the fuel reaches room temperature. Therefore, the fuel must be drained to FDT to be cooled down and kept subcritical. Evaluation for various cases of FDT produced the highest multiplication factor of 0.57008 ± 0.00004 at the most conservative condition. The multiplication factor is well below the critical state of 1.0. The evaluations suggest that soon after the control rods shut the reactor down, the fuel has to be drained to FDT to maintain shutdown condition and dissipate the decay heat.