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"Sampel penelitian adalah sampah industri baja Neomax di Jepang dengan basis ferrite. Identifikasi fase dengan XRD dan XRF memperlihatkan bahwa sampel merupakan senyawa strontium ferrite SrO.6Fe 2O3 fasa tunggal. Kurva XRD menunjukkan waktu milling 5, 10 dan 20 jam tidak signifikan terlihat perubahannya. Mikrograf SEM menunjukkan semakin lama waktu milling jumlah porositas (pori) semakin berkurang dan proses sintering telah memadatkan butiran -butiran grain kristal. Perbandingan Histerisis PERMAGRAPH menunjukkan milling dengan waktu yang lebih lama dan sintering dengan waktu yang lebih lama pada suhu sekitar 1000°C - 1300°C (dibawah titik leleh Fe) dapat meningkatkan nilai remanen magnetisasi Br, dengan kecenderungan nilai koersivitas Hc relatif tetap atau turun dalam batas tertentu."

"Material Bi1-xGdxFeO3 dengan nilai x=0, 0.06, 0.1, 0.2 dibuat melalui metode solgel autocombustion. Material dibuat denganprekursorFe(NO3)3.9H2O powder, Bi(NO3).6H2O powder, Gd(NO3)3.6H2O powder, H2O, dan citric acid (C6H8O7). Material ini di-sintering pada temperatur 750oC selama 3 jam setelah diperoleh gel. Pengaruh dari variasi doping Gd pada material BFO ini menjadi fokus yang akan dipelajari. Kemudian material ini akan dikarakterisasi dengan menggunakan X-Ray Diffraction (XRD), Permagraph, dan SEM Edax. Hasil karakterisasi XRD menunjukkan bahwa terjadi pembentukan dua fasa yang berbeda. Secara umum hasil pengujian Permagrapf pada suhu ruang menunjukkan bahwa material tersebut bersifat diamagnetik yang dikarenakan tingginya intensitas bismuth pada material.

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Bi1-xGdxFeO3material which is x = 0, 0.06, 0.1, 0.2 is made by the sol-gel method autocombustion. The material is made with the precursors of Fe(NO3)3.9H2O powder, Bi(NO3).6H2O powder, Gd(NO3)3.6H2O powder, H2O, andcitric acid (C6H8O7). Then the material will be sintered in 750° for three hours after the gel has been obtained. Effect of Gd doped BFO with variations of x is the main focus that will be learned. After that, this material will be characterized with X-Ray Diffraction (XRD), Permagraph, and SEM Edax.Result of XRD shows that there?re two differen phase. In general, the result of permagraf testing on room temperature shows that the material is kind of diamagnetic because of the high bismuth intensity on material."

"Duplex Stainless steel (DSS) 2205 is wedely used in shipbuilding industry as well as in gas and oil industry because its supenorit N in corrosion resistant and thoughness compared to other metals, during welding process, deformation may occur in DSS 2205. Line heating followed by quenching is often used to relieve deformation following welding process. Line heating applied to DSS 2205 may change microstructure and properties of the steel as well. There are many factors that affect the microstructure change during line heating process and one of them is the number of line heating passes applied to the material at the same location. This reseach examines microstructure and properties of DSS 2205 due to line heating process. Three samples of weld joints were line heated. Each sample were line heated once to and three times respectively in the direction perpendicular to thje weld line. Quanching in fresh water carried out following the line heating process. Each sample was cut into two pieces for metallography, hardness, and ferritescope test. Data obtained from metallography, hardness and ferrtescope tests showed that more line heating passes applied to the same location resulted in creasing ferrite contents increased 21.3% in base metal and 14.6% in weld metal. Ferritescope test showed that ferrite number (FN) increased 6.21 in base metal and 8.13% in weld metal. Hardness number of base metal increased 13 - 71%, 8.85% fusion line and 11.02% weld metal."

"Nanopartikel (NP) Mangan ferit (MnFe2O4) telah menyediakan platform serbaguna untuk mengembangkan sistem nano multifungsi untuk Magnetic Resonance Imaging (MRI) dan modalitas Single Photon Emmision Computed Tomography (SPECT). Di sini, kami mengembangkan NP Yodium-131 (131I)-bertanda nimotuzumab-MnFe2O4 baru sebagai MRI multimodalitas dan SPECT untuk diagnosis penyakit seperti kanker. Sintesis NP MnFe2O4 dilakukan dengan menggunakan ekstrak Piper nigrum (EPN). EPN berperan sebagai bahan sumber basa lemah dan zat penstabil yang menunjukkan adanya alkaloid, polifenol, serta terpenoid yang dikonfirmasi dari uji fitokimia. NP MnFe2O4 kemudian dikonjugasikan ke Epidermal Growth Factor Receptor (EGFR) nimotuzumab melalui PEG-linker heterobifungsional. Radiolabeling NP MnFe2O4 terkonjugasi nimotuzumab dengan Yodium-131 dilakukan dengan metode oksidasi iodobead. NP MnFe2O4 hasil sintesis dikarakterisasi dengan DRS, FTIR, XRD, SEM, TEM, dan EDX. NP MnFe2O4 yang dikonfirmasi memiliki bentuk bulat, dengan ukuran rata-rata sekitar 21 nm dengan bentuk kristal kubik fase tunggal. Nanopartikel menunjukkan sifat magnetisasi 23,4 emu/g sebagaimana dikonfirmasi oleh analisis VSM. Hasil konjugasi MnFe2O4 -nimotuzumab berhasil dilakukan dengan linker SH-PEG-NHS. Nanopartikel 131I-bertanda nimotuzumab-MnFe2O4 ​​yang disiapkan memberikan kemurnian radiokimia yang sangat baik sebesar 93,57 ± 0,52%. Investigasi biologis di masa depan dari NP MnFe2O4-nimotuzumab-131I baru ini sebagai nanoprobe MRI dan SPECT baik in vitro dan in vivo masih diperlukan

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Manganese ferrite (MnFe2O4) nanoparticles (NPs) has provided versatile platform to develop multifunctional nanosystem for magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) modalities. Herein, we develop novel iodine-131-labeled-nimotuzumab-MnFe2O4 NPs as multimodalities MRI and SPECT nanoprobe for diagnosis of disease such as cancer. The synthesis of MnFe2O4 NPs were done using Piper nigrum extract (PNE). PNE plays role as a weak base source material and stabilizing agent which showed the presence of alkaloids, polyphenols, as well as terpenoids as confirmed from the phytochemical test. MnFe2O4 NPs were then conjugated to anti-epidermal growth factor receptor (EGFR) nimotuzumab via heterobifunctional PEG-linker. The radiolabeling of nimotuzumab-conjugated MnFe2O4 NPs with iodine-131 was performed using iodobead oxidizing method. The synthesized MnFe2O4 NPs were characterized by DRS, FTIR, XRD, XRD, SEM, TEM, and EDX. The confirmed MnFe2O4 NPs have a spherical shape, with an average size of about 21 nm with a single-phase cubic crystal form. The NPs showed magnetization properties of 23.4 emu/g as confirmed by VSM analysis. The results of the conjugation of MnFe2O4-nimotuzumab were successfully carried out with the SH-PEG-NHS linker. The prepared iodine-131-labeled-nimotuzumab-MnFe2O4 NPs gave an excellent radiochemical purity of 93.57 ± 0.52 %. Future biological investigations of this novel iodine-131-labeled-nimotuzumab-MnFe2O4 NPs as MRI and SPECT nanoprobe both in vitro and in vivo are required. "

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Bismuth Ferrite, BiFeO₃ (BFO) merupakan material yang memperlihatkan sifat ferroelektrik yang baik dan sifat ferromagnetik yang lemah. Lemahnya sifat ferromagnetik material BFO ini disebabkan adanya sifat antiferromagnetik sikloid tipe G. Salah satu upaya meningkatkan sifat ferromagnetik BFO ini adalah dengan mendoping atom Bi yang berada pada posisi A didalam senyawa ABO₃ menggunakan Li (Bi_1-xLi_xFeO₃, x= 0,02, 0,04, 0,06) dan Zn (Bi_1-zZn_zO₃, z= 0,05, 0,1, 0,15). Proses sintesis doping BFO tersebut dilakukan menggunakan metode sol-gel. Dari sampel hasil doping tersebut diketahui bahwa keberadaan Li dan Zn telah memicu terjadinya kenaikan saturasi magnetik didalam BFO. Kenaikan sifat magnetik ini diakibatkan oleh pengecilan sudut Fe–O–Fe. Pengecilan sudut ini disebabkan oleh perubahan rasio kisi c/a kristal BFO didalam struktur rombohedral dengan spacegroup (s.g.) R3c. Kenaikan sifat magnetik didalam sampel BFO hasil doping tersebut disertai munculnya Fe²⁺ dan terbentuknya vakansi oksigen sebagai kompensasi atas keberadaan Li¹⁺ dan Zn²⁺ yang menggantikan posisi Bi³⁺. Keberadaan Li didalam BFO teridentifikasi pada energi ikat sebesar 56,7 eV menggunakan XPS. Penggunaan metode sol-gel didalam proses preparasi sampel diketahui efektif untuk menghasilkan bubuk sampel berskala nano (<200 nm).

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Bismuth Ferrite, BiFeO₃ (BFO) is a material that shows excellent ferroelectric properties and weak ferromagnetic properties. The weak ferromagnetic properties of BFO material are due to the antiferromagnetic nature of cycloid type G. One effort to improve the ferromagnetic properties of BFO is to dope Bi atoms in position A in the compound ABO₃ using Li (Bi_1-xLi_xFeO₃, x= 0,02, 0,04, 0,06) and Zn (Bi_1-zZn_zO₃, z= 0,05, 0,1, 0,15). The BFO doping synthesis process was carried out using the sol-gel method. From the doping sample, it is known that the presence of Li and Zn has triggered an increase in magnetic saturation in BFO. This increase in magnetic properties was caused by the reduction of Fe – O – Fe angle. This reduction in angle is caused by changes in the lattice ratio of c / a BFO crystals in the rhombohedral structure to the spacegroup (s.g.) R3c. The increase in magnetic properties in the doped BFO sample is accompanied by the appearance of Fe²⁺ and the formation of oxygen vacancy as compensation for the presence of Li¹⁺ and Zn²⁺ which replace the position of Bi³⁺. Li's presence in BFO was identified in the binding energy of 56.7 eV using XPS. The use of the sol-gel method in the sample preparation process is known to be effective for producing nanoscale sample powders (<200 nm). 

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