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"Buku "Express and standard : ductile iron pipelines" ini membahas tentang spesifikasi pipa besi."

"Provides a solid overview of the important metallurgical concepts related to microstructures of irons and steels, and it provides detailed guidelines for the proper metallographic techniques used to reveal, capture, and understand microstructures."

"Ion tripolifosfat (P3O10-5) merupakan salah satu bentuk fosfat yang umumnya ditemukan pada limbah deterjen. Apabila tidak diolah dapat menyebabkan eutrofikasi (blooming alga). Karbon aktif yang dimodifikasi dengan besi oksida dapat digunakan untuk mengurangi jumlah ion tripolifosfat. Karbon aktif dibuat dengan memanfaatkan limbah lindi hitam hasil samping produksi bioetanol. Preparasi komposit karbon aktif/besi oksida dilakukan dengan menambahkan larutan besi dari FeSO4.7H2O ke dalam karbon aktif. Hasil karakterisasi menggunakan difraksi sinar-X menunjukan bahwa besi oksida yang terbentuk pada komposit karbon aktif/besi oksida merupakan fase goethite (α-FeOOH) dan berdasarkan data EDX jumlah kandungan besi yang terdapat pada kompossit karbon aktif/besi oksida adalah 17%. Kinerja komposit karbon aktif/besi oksida terhadap adsorpsi ion tripolifosfat dievaluasi berdasarkan uji variasi konsentrasi larutan awal tripolifosfat, pH, kecepatan agitasi dan waktu kontak. Persentase efisiensi maksimum ion tripolifosfat mencapai 96,87% dengan kapasitas adsorpsinya 1,5992 mg/g pada pH 3, konsentrasi awal larutan tripolifosfat 3 mg/L dan dosis adsorben 0,1 g. Hasil tersebut menunjukan bahwa karbon aktif yang dikompositkan dengan besi oksida memiliki efektifitas dan efisiensi yang tinggi untuk menurunkan ion tripolifosfat. Pada penelitian ini juga dilakukan desorpsi fosfat menggunakan medium asam sulfat, asam sitrat dan akuades. Jumlah fosfat yang terdesorpsi lebih besar dalam medium asam sulfat dengan persentase desorpsinya sebesar 87,71% selama 9 jam.

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Tripolyphosphate ion, known as P3O10-5, is one of phosphate forms which mostly recognized in the laundry wastewater. The abundant quantities of trpolyphosphate ions in the water resources potentially lead eutrophication or algae blooming therefore it damaged the inside-living organisms. To mitigate excess ion, activated carbon was modified with iron oxide can be used to remove the amount of tripolyphosphate ions. Activated carbon was made by utilizing black liquor waste water from bioethanol side-production. Activated carbon/iron oxide composites were prepared by introducing activated carbon into iron solution made from FeSO4.7H2.

The result from X-ray diffraction characterization showed the main iron oxide actually present in the composites was goethite (α-FeOOH) and based on the result of SEM-EDX measurement it contained 17% of iron element. The performance of activated carbon/iron oxide composites on the adsorption of tripolyphosphate ions was evaluated by various initial concentrations of tripolyphosphate solutions, which were adsorbent dose, pH, mixing speed, and contact time. The maximum efficiency percentage of tripolyphosphate ions reached 96.87% with adsorption capacity of 1,5992 mg/g at an initial tripolyphosphate concentration of 3 mg/L, solution pH of 3 and 0,1 g of adsorbent dose.

The results indicated that activated carbon/iron oxide were more effective to decrease tripolyphosphate ions than only activated carbons. This study also conducts desorption experiments of phosphate on sulfuric acid, citric acid, and aquades solutions. Amount of phosphate desorption in sulfuric acid medium was the highest desorption percentage around 87,717% within 9 hours."

"A complete introduction to titanium and its alloys, with coverage of all technical aspects of titanium with sufficient metals property data for most users. For users at any level of experience with titanium, providing both technical information and an executive summary of the metal and its uses. DLC: Titanium."

"Ceramic magnets with the chemical composition of barium hexaferrite (BaFe12O19) were obtained through the synthesis of magnetite powder from iron sand taken from the Southern Coast of Yogyakarta in Indonesia. The iron sand was dissolved and then synthesized to produce magnetite powder. Subsequently, the magnetite powder was oxidized at temperatures of 700, 900, and 1100°C for five hours to produce hematite. The un-oxidized magnetite and the magnetite which was oxidized at the different temperatures were each mixed with barium carbonate, respectively. The mixtures were then calcined at 1100°C for two hours. The calcined products were compacted and then sintered at 1100°C for one hour to produce sintered ceramic magnets. X-ray diffraction (XRD), a vibrating sample magnetometer (VSM), a scanning electron microscope (SEM) with an energy dispersive X-ray spectroscope (EDS), and thermogravimetry analysis (TGA) were used to characterize the ceramic magnets. The results showed the magnetite that was directly calcined, compacted, and sintered had a BaFe12O19 phase and also had the presence of a Fe2O3 phase with a BH(max) of 0.26 MGOe, Hc of 1.27 kOe, and Ms of 31.421 emu/g. The sintered ceramic magnet which was initially oxidized at a temperature of 900°C had a BaFe12O19 phase with a BH(max) of 0.78 MGOe, Hc of 1.95 kOe, and Ms of 46.970 emu/g. These results indicate satisfactory results as a permanent magnet. Thus, the iron sand from the Southern Coast of Yogyakarta in Indonesia has potential for the production of ceramic permanent magnets."

"ABSTRAKReduction of free fatty acid (FFA) in used palm oil was determined after treatment of waste cooking oil with an adsorbent derived from coffee bean husk ash. Coffee husks were burned at 600 ºC for 12 hrs to obtain the adsorbent ash. Free fatty acid removal efficiency was optimized with respect to ash dosage, contact time and temperature. It was found that shaking ash (1 g) with waste palm oil (50 g) at 250 rpm and 30°C for 330 min gave the highest reduction in free fatty acids (FFA) (1966 mg/g). The adsorption isotherm was followed by Temkin (R2 = 0.9283) and Freundlich models (R2 = 0.9146). The adsorption of FFA at all adsorbent doses followed pseudo-second order kinetics (R2 = 0.9817-0.9999). A thermodynamic study revealed that the changes in enthalpy, entropy and Gibbs free energy were 89.07 kJ/mol, -0.25 kJ/mol.K and -5.15 to -12.17 kJ/mol, respectively. The coffee husk ash (5 g ash / 50 g waste palm oil) was found to reduce FFA by 100% at 30°C.KeywordsCoffee husk, Used palm oil, Free fatty acid, Adsorption, Ash"