Titanium dioxide (T1O2) is well known as the most active and stable semiconductor as an environmentally friendly photocatalytic material to degrade pollutants in aqueous and gas. In this research, TiO2 thin film was synthesized on a stainless steel surface using DC sputtering method. To enhance the photocatalytic activity, the TiO2 thin film was doped with a silver (Ag) also using DC sputtering method. The surface morphology, chemical composition, and crystal structure of the thin film were characterized using scanning electron microscopy –energy dispersive spectroscopy (SEM-EDX) and X-rays diffraction (XRD), respectively. Based on SEM-EDX analysis, it’s found that the content of silver (Ag) is 10.5 % weight or 2.56 % at.. This condition was achieved for 2 minutes of deposition time. The photocatalytic activity of TiO2 and TiO2-Ag thin film was studied using UV light and sunlight. As a model pollutant, it’s used methylene blue. It’s found that, if the film exposure using UV light, the absorbance for TiO2 film is 35.85 % and 64.26 % for TiO2-Ag thin film. If the film exposure using sunlight, the absorbance for TiO2 film is 17.5 % and 76.74 % for TiO2-Ag thin film. It can be concluded that the effect of Ag doping can enhance the photocatalytic activity of the thin film.

IRADIATOR STTN: OVERVIEW DESAIN MANAJEMEN KESELAMATAN DAN KESEHATAN KERJA. Iradiator gamma STTN dapat memberi kebermanfaatan yang besar sebagai fasilitas yang mendukung tridharma perguruan tinggi. Namun secara bersamaan memiliki potensi resiko karena membawa sumber radioaktif  yang cukup besar yakni Co-60 12 kiloCurie. Oleh karena itu, dalam penggunaan fasilitas iradiator harus disusun dan diterapkan sistem manajemen keselamatan dan kesehatan kerja (SMK3) dalam rangka pengendalian risiko yang berkaitan dengan kegiatan kerja dengan sumber radiasi, guna tercipta tempat kerja yang aman, efisien dan produktif. Dari penggabungan semua sistem K3 dan penjaminan mutu yang mengacu pada garis peraturan yang berlaku maka dapat ditarik empat pilar manajeman dalam pemanfaatan Iradiator STTN yang meliputi planning (perencanaan), organizing (pengorganisasian), leading (pengarahan) dan controlling (pengendalian). Dalam hal ini planning meliputi pemilihan tipe irradiator, desain ruang/bangun, dan kualifikasi SDM;                 organizing dilakukan dengan adanya struktur organisasi pengelola irradiator; leading dengan pengarahan untuk optimalisasi pelayanan; dan controlling yang meliputi kontrol terhadap pengoperasian, perawatan, data personil, dan paparan lingkungan.

Crystalline hydroxyapatite (HA) prepared from duck eggshell using the precipitation method. Duck eggshell used because it has higher calcium oxide (CaO) purity than another eggshell. The amount of duck eggshell calcinated to obtain calcium precursor then dropped with phosphoric acid wisely. The hydroxyapatite result modified with a silver (HA-Ag) using gamma radiolysis reduction. Hydroxyapatite powder added with an alcoholic silver ion precursor and followed by high energy gamma irradiation. This modification is to increase the antibacterial activity of hydroxyapatite for further medical applications. The results of the bacterial inhibitory test, showed the largest antibacterial clear zone in 25 kGy irradiation dose of HA-Ag. HA and HA-Ag characterized by FTIR, XRD, SEM and EDX. All characterization result support the forming of pure hydroxyapatite and the presence of a silver particle.

Electroactive materials with excellent performance are developed to be applied in different fields. In this study, Graphene Oxide (GO) was synthesized using the Hummer method then reduced and modified with Cu trough gamma irradiation (radiolytic reduction) for dose variations. The optimum dose that produces the highest electroactive is 35 kGy which was tested with cyclic voltammetry. The results of FTIR analysis show the characteristics of functional groups found in GO and rGO are different. The modification of rGO with Cu was successfully shown from the results of XRD and SEM-EDX analysis. The results of the XRD analysis showed that there are two peaks at position 2 theta 10.58° which showed the presence of GO and at position 2 theta 42.55° which indicates the presence of Cu. The results of the SEM-EDX analysis showed that there is 2.25% wt of Cu on the surface of the rGO.