Adisi Fe2O3 danSiCPada Material MgH2 untuk Aplikasi Tangki Penyimpanan Hidrogen Kendaraan Fuel Cell

The preliminary studies on MgH2 as hydrogen storage material by inserting dual catalysts, iron oxide and silicon carbide (5wt% Fe2O3 and SiC), has been done. The sample was prepared using reactive ball milling technique for 10 hours. The milling process was done under 10 bar hydrogen pressure. Phase investigation using X-ray diffraction showedthat after 10 hours of milling, the MgH2 emerged as the dominant phase and the crystallite size decreased to nanometer scale. The morphological observation obtained by scanning electron microscope showed that the powder material surface is irregular, as a result of repeated during the milling process. Finally,DTA scan showed the onset temperature at 354o Cwhich is still high for the automotive application. Keywords: hydorgen storage, magnesium, metal oxide, silicon carbide, millin

The Effect of Magnetite (Fe3o4)catalyst From Iron Sands on Desorption Temperature of Mgh2 Hydrogen Storage Material

One of the future technologies for a safe hydrogen storage media is metal hydrides. Currently, Mg-based metal hydride has a safety factor and efficient for vehicle applications. However, the thermodynamic properties of magnesium hydride (MgH2) found a relatively high temperature. High desorption temperatures caused MgH2 high thermodynamic stability resulting desorption enthalpy is also high. In this study, natural mineral (iron ore) has been extracted from iron sand into powder of magnetite (Fe3O4) and used as a catalyst in an effort to improve the desorption properties of MgH2. Magnetie has been successfully extracted from iron sand using precipitation method with a purity of 85 % , where the purity of the iron sand before extracted was 81%. Then, MgH2-Fe3O4 was milling using mechanical alloying method with a variety of catalysts and milling time. The observation by XRD showed the material was reduced to nanocrystalline scale. MgH2 phase appears as the main phase. DSC test results showed with the addition of Fe3O4, the desorption temperature can be reduced up to 366oC, compared to pure pure MgH2 reached by 409o C. Furthermore, based on gravimetric test, the hydrogen release occurs at a temperature of 388o C, weight loss of 0.66 mg during 16 minutes

Studies of Relation Between Turbidity and Refractive Indeks of Bottled Water in the Area of Banda Aceh by Using Interferometer Murty Method

Bottled water is clean water ready to drink quickly without cooking however, it is not all of the bottled water have a good quality. The quality of water can be observed from the optical properties of water, such as clarity and refractive index. A study has been carried out by using interferometer Murty method to know the relation between turbidity and refractive index of the bottled water. The refractive index measurement was carried out for 20 samples from 10 brands of the bottled water. The result of refractive index measurement shows that the refractive index of the water is about 1,1, in averge on the other hand the refractive index of water based on literature is 1,33. Along with the refractive index measurement by using interferometer Murty, turbidity was also measured by using Turbidimeter. The result of measurement show that there is a relation between turbidity and refractive index. The deviation of refractive index values obtained in this measurement from the literature data is because there are some error in the measurement process. By improving the error, better measurement will allow the interferometer Murty to be used to inspect water clarity

Studies of Relation Between Turbidity and Refractive Indeks of Bottled Water in The Area of Banda Aceh by Using Interferometer Murty Method

Bottled water is clean water ready to drink quickly without cooking however, it is not all of the bottled water have a good quality. The quality of water can be observed from the optical properties of water, such as clarity and refractive index. A study has been carried out by using interferometer Murty method to know the relation between turbidity and refractive index of the bottled water. The refractive index measurement was carried out for 20 samples from 10 brands of the bottled water. The result of refractive index measurement shows that the refractive index of the water is about 1,1, in averge on the other hand the refractive index of water based on literature is 1,33. Along with the refractive index measurement by using interferometer Murty, turbidity was also measured by using Turbidimeter. The result of measurement show that there is a relation between turbidity and refractive index. The deviation of refractive index values obtained in this measurement from the literature data is because there are some error in the measurement process. By improving the error, better measurement will allow the interferometer Murty to be used to inspect water clarity

SYNTHESIS AND CHARACTERIZATION OF HEMATITE (Fe2O3) EXTRACTED FROM IRON ORE BY PRECIPITATION METHOD

Indonesia has a lot of mining material of iron ore that could be used for various purposes in the steel industry or for other. This research, has synthesized and characterization of hematite from local iron ore from Lhoong area by precipitation mechanism. The iron ore powder was magnetic separation with magnet then mixed with HCl and NH4OH. Then, it was dried at temperature of 150 ºC and calcinated at 500º C for 2 hours. Characterizations were perfomed using X-ray Diffraction (XRD) and X-ray Fluorescence (XRF). As the results, it was found that the magnetic separation iron ore showed the composition of Fe2O3 (95.99%), SiO2 (2.10%). Then, by precipitation mechanism, the composition of Fe2O3 found around 96.58%. Next, the synthesis result are characterized with XRD show that the main phase is dominan in iron ore of Lhoong is hematit (Fe2O3). Scherrer calculations showed that precipitation mechanism to reducing grain size, the process of magnetic separation (58.009 µm) and the precipitation mechanism (20.950 µm.

Identification of Oxide Compound in Dolomite Mineral from Aceh Tamiang Region

Indonesia has abundant mineral especially carbonate-based mineral, ike dolomite. Particularly in Aceh province's, the largest dolomite deposits is available in Aceh Tamiang district around 1.9 billion tons. Unfortunately, current use of dolomite in the industry and other applications is still limited. In this work we report the advanced preparation of dolomite using calcinations method. Whereas, with this method, the dolomite mineral can be processed into calcium and magnesium oxide which has a very wide field of application and higher values. To obtain optimal results, we also identify the effect of temperature on the formation of oxide compounds. Preliminary study using XRF founded that dolomite in village Selamat is known as the highest concentration of CaO (61.20%) followed by MgO (25.28%). It is also showed that the main phase obtained by XRD is dolomite (CaMg(CO3)2). Furthermore, after the calcinations process at 700 °C, it was founded that the formation of dolomite were CaCO3 and MgO, whereas at temperatures of 900 °C mostly the CaCO3 has decomposed into CaO. SEM observations showed that dolomite has the composition of particles distributed homogeneously along the particle agglomerate when it calcinations

SYNTHESIS AND CHARACTERIZATION OF HEMATITE (Fe2O3) EXTRACTED FROM IRON ORE BY PRECIPITATION METHOD

Indonesia has a lot of mining material of iron ore that could be used for various purposes in the steel industry or for other. This research, has synthesized and characterization of hematite from local iron ore from Lhoong area by precipitation mechanism. The iron ore powder was magnetic separation with magnet then mixed with HCl and NH4OH. Then, it was dried at temperature of 150 ºC and calcinated at 500º C for 2 hours. Characterizations were perfomed using X-ray Diffraction (XRD) and X-ray Fluorescence (XRF). As the results, it was found that the magnetic separation iron ore showed the composition of Fe2O3 (95.99%), SiO2 (2.10%). Then, by precipitation mechanism, the composition of Fe2O3 found around 96.58%. Next, the synthesis result are characterized with XRD show that the main phase is dominan in iron ore of Lhoong is hematit (Fe2O3). Scherrer calculations showed that precipitation mechanism to reducing grain size, the process of magnetic separation (58.009 µm) and the precipitation mechanism (20.950 µm.

Pengembangan dan Implementasi Modul Fisika Berbasis Saintifik pada Materi Alat Optik untuk Meningkatkan KPS Siswa di SMA Negeri 5 Banda Aceh

Penelitian ini dilakukan untuk mengetahui efektifitas implementasi modul fisika berbasis pendekatan saintifik dalam meningkatkan keterampilan proses sains siswa pada materi alat-alat optik di SMA Negeri 5 Banda Aceh. Metode yang digunakan dalam penelitian ini adalah metode quasi experimental design, desain penelitian ini hanya menggunakan  satu kelompoks aja, sehingga tidak memerlukan kelompok kontrol. Jenis penelitian yang digunakan adalah pengembangan dan implementasi dengan menggunakan model ADDIE. Pembelajaran melalui implementasi modul fisika berbasis pendekatan saintifik pada materi alat-alat optik efektif meningkatkan keterampilan proses sains. Hal ini dapat dilihat dari nilai rata-rata skor keterampilan proses sebelum diberikan perlakuan sebesar 46,09%, dan setelah diberikan perlakuan didapatkan sebesar 76,74%

PENGARUH PENGGUNAAN MEDIA KOMPUTER BERBASIS SIMULASI PHYSICS EDUCATION TECHNOLOGY (PhET) TERHADAP HASIL BELAJAR DAN KETERAMPILAN BERFIKIR KRITIS SISWA PADA MATERI FLUIDA STATIS

Penelitian ini bertujuan untuk mengetahui peningkatan hasil belajar dan keterampilan berfikir kritis pada pelajaran fisika konsep fluida statis dengan menggunakan media komputer berbasis simulasi PhET dengan pembelajaran konvensional. Metode penelitian yang digunakan adalah metode eksperimen dan desain kontrol group pretes postes. Populasi dalam penelitian ini adalah seluruh siswa kelas XI IPA. Teknik pengambilan sampel dilakukan dengan cara cluster random sampling yang memiliki kemampuan yang sama, tanpa mengacak siswa tiap kelasnya. Pengelompokan sampel terdiri dari dua kelas di sekolah MAN Rukoh Banda Aceh. Teknik pengumpulan data dilakukan dengan menggunakan tes tertulis berupa soal pilihan ganda sebanyak 20 soal pretes dan postes. Hasil uji t menunjukkan Hasil penelitian menunjukkan bahwa terjadinya perbedaan peningkatan hasil belajar dan keterampilan berfikir kritis siswa pada kelas kontrol dan kelas eksperimen. Kelas eksperimen yang menggunakan simulasi PhET mengalami peningkatan hasil belajar dan keterampilan berfikir kritis yang lebih tinggi daripada kelas kontrol yang menggunakan pembelajaran konvensional