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"ABSTRAKPercampuran serbuk baja ODS Oxide Dispersion Strengthened pada umumnya menggunakan metode mekanik dengan ball mill, namun selama pembuatannya disertai pembentukan oksida. Percampuran serbuk dengan metode iradiasi ultrasonik merupakan metode baru yang memberikan keuntungan berupa membentuk microalloying partikel dan meminimalisasi pembentukan fasa oksida. Penelitian ini mempelajari tentang pengaruh amplitudo 20, 30, 40 dan waktu perlakuan 20jam, 30 jam terhadap reduksi ukuran partikel dan pembentukan microalloying Fe-Cr. Serbuk dibagi menjadi 7 sampel dengan sampel A perlakuan pencampuran mortar, iradiasi ultrasonik sampel B1 A:20, t: 20 jam, sampel B2 A:30, t:20 jam, sampel B3 A:40, t:20 jam, sampel C1 A:20, t:30 jam, sampel C2 A:40, t:30 jam, dan sampel C3 A:40, t:30 jam yang kemudian dikarakterisasi menggunakan SEM, EDS, dan XRD. Hasil penelitian ini adalah pada iradiasi ultrasonik selama 20 jam menghasilkan ukuran partikel sampel B1>sampel B2>sampel B3 adalah 5.326 m>4.769 m>4.563 m. Sedangkan pada iradiasi ultrasonik selama 30 jam menghasilkan ukuran partikel sampel C1>sampel C2>sampel C3 adalah 4.605 m>3.719 m>3.608 m. Komposisi Fe-Cr yang terbentuk adalah sampel A: sampel B1: sampel B2: sampel B3:sampel C1:sampel C2: C3 adalah 0:48.85:26.07:2478:89:81.94:42.98. Hasil tersebut menunjukan bahwa semakin besar amplitudo, microalloying Fe-Cr yang terbentuk menjadi semakin rendah, penambahan waktu perlakuan justru meningkatkan presentase Fe-Cr yang terbentuk. Pada ultrasonik selama 20 jam, nilai crystallite size Fe-Cr sampel B1>sampel B2>sampel B3 adalah 292.72 nm>246.76 nm>184.77 nm dan nilai microstrains Fe-Cr sampel B1184.34 nm dan nilai microstrains Fe-Cr sampel C1< sampel C2.

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ABSTRACTThe mixing of ODS Oxide Dispersion Strengthened powder generally uses mechanical method with ball mill, but during its manufacture with oxide formation. Powder mixing with ultrasonic irradiation method is a new method that provides the advantage of forming microalloying particles and minimizing the formation of the oxide phase. This study studied the effect of amplitude 20, 30, 40 and treatment time 20h, 30h on particle size reduction and formation of Fe Cr microalloying. The powder was divided into 7 samples with sample A mortar mixing treatment, ultrasonic irradiation of sample B1 A 20, t 20 hours, sample B2 A 30, t 20 hours, sample B3 A 40, T 20 hours, sample C1 A 20, t 30 hours, C2 sample A 40, t 30 hours, and C3 sample A 40, t 30 hours Which is then characterized using SEM, EDS, and XRD. The results of this study were on ultrasonic irradiation for 20 hours yielding sample particle size B1 sample B2 B3 sample was 5,326 m 4,769 m 4,563 m. While on ultrasonic irradiation for 30 hours resulted in particle size of sample C1 C2 sample C3 sample is 4,605 m 3,719 m 3,608 m. The composition of Fe Cr formed is sample A sample B1 sample B2 sample B3 sample C1 sample C2 C3 is 0 48.85 26.07 24.78 89 81.94 42.98. These results show that the greater the amplitude, the lower the Fe Cr microalloying that is formed, the added time of treatment actually increases the Fe Cr percentage that is formed. At ultrasonic for 20 hours, the crystallite size of Fe Cr sample B1 sample B2 B3 sample is 292.72 nm 246.76 nm 184.77 nm and the Fe Cr microstrains value of sample B1 198.02 nm 184.34 nm and the Fe Cr microstrains value of sample C1."

"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."

"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."

"Senyawa golongan kuinazolinon memiliki aktivitas biologis yang luas. Salah satunya adalah senyawa 2-[(E)-2-feniletenil]-3,4-dihidrokuinazolin-4-on yang memiliki aktifitas antibakteri. Aktivitas antibakteri paling efektif ditunjukkan oleh turunan senyawa kuinazolinon dengan cincin benzena yang tidak tersubstitusi atau tersubstitusi oleh substituen kecil dan cincin pirimidin yang tersubstitusi oleh substituen besar. Dalam rangka memperoleh senyawa turunan kuinazolinon baru yang diperkirakan memiliki aktivitas antibakteri, telah dilakukan sintesis senyawa 6-amino-2-[(E)-2-feniletenil]-3,4-dihidrokuinazolin-4-on. Sintesis dilakukan melalui empat tahap. Tahap 1, sintesis 2-metil-3,4-dihidrokuinazolin-4-on (1) dari antranilamida dan asetamida dengan iradiasi microwave. Tahap 2, sintesis 2-metil-6- nitro-3,4-dihidrokuinazolin-4-on (2) dari nitrasi 2-metil-3,4-dihidrokuinazolin-4-on dengan asam nitrat pekat berasap dan asam sulfat pekat. Struktur molekul produk 1 dan 2 telah dikonfirmasi dengan FT-IR. Tahap 3, sintesis 6-nitro-2-[(E)-2-feniletenil]-3,4-dihidrokuinazolin-4-on (3) dari kondensasi Knoevenagel 2-metil-6-nitro-3,4-dihidrokuinazolin-4-on dan benzaldehida. Tahap 4, sintesis 6-amino-2-[(E)-2-feniletenil]-3,4-dihidrokuinazolin-4-on (4) dari reduksi 6-nitro-2-[(E)-2-feniletenil]-3,4-dihidrokuinazolin-4-on dengan serbuk besi, dan asam klorida pekat menggunakan ultrasonik. Struktur molekul produk 3 dan 4 telah dikonfirmasi dengan FT-IR dan 1H-NMR. Hasil penelitian menunjukkan bahwa produk hasil sintesis sudah sesuai dengan senyawa yang diharapkan dengan nilai rendemen tahap 1 sebesar 90,19%; tahap 2 sebesar 79,61%; tahap 3 sebesar 42,04% dan tahap 4 sebesar 72,24%.

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Quinazolinone derivatives have wide spectrum of biological activity. One of them is 2-[(E)-2-phenylethenyl]-3,4-dihydroquinazolin-4-one which have antibacterial activity. The most effective antibacterial activity were showed by quinazolinone derivative with an unsubstituted benzene ring or substituted with one small substituents and a pyrimidine ring substituted with large substituents. To get a novel quinazolinone derivative which predicted to have antibacterial activity, 6-amine-2-[(E)-2-phenylethenyl]-3,4-dihydroquinazolin-4-one has been synthesized. There were four stages of synthesis. First, synthesis of 2-methyl-3,4-dihydroquinazolin-4-one (1) from antranilamide and acetamide by microwave irradiation. Second, synthesis of 2-methyl-6-nitro-3,4-dihydroquinazolin-4-one (2) by nitration of 2-methyl-3,4-dihydroquinazolin-4-one with nitric acid fuming and concentrated sulfuric acid. The structure of first and second products was confirmed using FT-IR. Third, synthesis of 6-nitro-2-[(E)-2-phenylethenyl]-3,4-dihydroquinazolin-4-one (3) by Knoevenagel condensation of 2-methyl-6-nitro-3,4-dihydroquinazolin-4-one and benzaldehyde. Fourth, synthesis of 6-amine-2-[(E)-2-phenylethenyl]-3,4-dihydroquinazolin-4-one (4) by reduction of 6-nitro-2-[(E)-2-phenylethenyl]-3,4-dihydroquinazolin-4-one with iron powder and concentrate hydrocloric acid using ultrasonic. The structure of third and fourth products was confirmed using FT-IR and 1H-NMR. The results showed that the synthesized products are in confirmity with the expected compound with 90,19% yield for first stage; 79,16% yield for seconde stage; 42,04% yield for third stage and 72,24% yield for fourth stage."

"Kasus resistensi terhadap antibakteri memicu kebutuhan akan adanya antibakteri baru. Kuinazolin-4-on memiliki spektrum aktivitas biologi yang luas, salah satunya adalah antibakteri. Dihidrofolat reduktase merupakan enzim yang penting dalam biosintesis asam nukleat bakteri. Senyawa turunan kuinazolin-4-on dengan substitusi pada posisi 2- dan 6- dapat menghambat aktivitas dihidrofolat reduktase. Penambahan gugus stiril pada posisi 2- dapat menyebabkan kerusakan sel mikroorganisme. Adanya gugus amina pada posisi 6- bersifat aktif sebagai antimikroba. Dalam rangka memperoleh senyawa turunan kuinazolin-4-on lainnya telah dilakukan sintesis senyawa baru 6-amino-2-[(E)-2-(4-hidroksifenil)etenil]-3,4-dihidrokuinazolin-4-on yang dilakukan dalam empat tahap. Tahap pertama adalah sintesis 2-metil-3,4-dihidrokuinazolin-4-on dari antranilamida dan asetamida menggunakan microwave. Tahap kedua adalah sintesis 2-metil-6-nitro-3,4-dihidrokuinazolin-4-on menggunakan asam nitrat berasap dan asam sulfat pekat. Tahap ketiga adalah sintesis 2-[(E)-2-(4-hidroksifenil)etenil]-6-nitro-3,4-dihidrokuinazolin-4-on dari 2-metil-6-nitro-3,4-dihidrokuinazolin-4-on dan 4-hidroksibenzaldehida dalam asam asetat glasial menggunakan microwave. Tahap keempat adalah sintesis 6-amino-2-[(E)-2-(4-hidroksifenil)etenil]-3,4-dihidrokuinazolin-4-on menggunakan serbuk besi dalam asam klorida pekat dengan sonikasi. Struktur molekul senyawa produk tahap satu dan dua dikonfirmasi dengan FT-IR, sedangkan senyawa tiga dan empat dikonfirmasi dengan FT-IR dan 1H NMR. Hasil penelitian menunjukkan bahwa produk sintesis telah sesuai dengan senyawa yang diharapkan dengan persen perolehan tahap satu 90,19%, tahap dua 79,61%, tahap tiga 67,45% dan tahap empat 52,91%.

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Antibacterial resistance cases have triggered the necessity of new antibacterial agents. Quinazolin-4-one has a wide spectrum of biological activities, one of them is antibacterial. Dihydrofolate reductase is the important enzyme in the biosynthesis of nucleic acid. Inhibition of dihydrofolate reductase will cause cell death. The series of 2,6-substitued-quinazolin-4-one have the inhibition activities of dihydrofolate reductase. Addition of styryl compound in 2-substitued-quinazolin-4-on can cause the damage of microorganism cells. Amine group in 6-substitued-quinazolin-4-one have the characteristic as antibiotic.

In order to obtain another derivate of quinazolin-4-one, a new 6-amino-2-[(E)-2-(4-hydroxyphenyl)ethenyl]-3,4-dihydroquinazolin-4-one had been synthesized in four stages. First stage was microwave-assisted synthesis of 2-methyl-3,4-dihydroquinazolin-4-one from anthranilamide and acetamide. Second stage was synthesis of 2-methyl-6-nitro-3,4-dihydroquinazolin-4-one using fuming nitric acid and concentrated sulfuric acid. Third stage was microwave-assisted synthesis of 2-[(E)-2-(4-hydroxyphenyl)ethenyl]-6-nitro-3,4-dihydroquinazolin-4-one from 2-methyl-6-nitro-3,4-dihydroquinazolin-4-one and 4-hydroxybenzaldehide in glacial acetic acid. Fourth stage was synthesis of 6-amino-2-[(E)-2-(4-hydroxyphenyl)ethenyl]-3,4-dihydroquinazolin-4-one using iron powder in concentrated hydrochloride acid with sonication. Molecular structure of the first and second compound was confirmed by using FT-IR while the third and fourth compound was confirmed by using FT-IR and 1H NMR. Result of the research shows that the final product is in conformity with the expected compound with 90,19% yield for first stage, 79,61% second stage, 67,45% third stage, and 52,91% fourth stage."

"Senyawa turunan kuinazolin-4(3H)-on telah diketahui memiliki aktivitas farmakologis yang luas. Senyawa 2-stirilkuinazolin-4(3H)-on secara khusus memiliki aktivitas penghambatan polimerisasi tubulin, Epidermal Growth Factor Receptor, dan dihidrofolat reduktase yang berperan penting dalam terjadinya tumor. Pada penelitian ini, dilakukan sintesis senyawa baru turunan 2-stirilkuinazolin-4(3H)-on tersubstitusi pada posisi 6, yaitu 6-amino-2-[(E)-2-[4-(dimetilamino)fenil]etenil]-3,4-dihidrokuinazolin-4-on. Sintesis dilakukan dalam empat tahap: sintesis 2-metilkuinazolin-4(3H)-on, nitrasi membentuk 2-metil-6-nitrokuinazolin-4(3H)-on, kondensasi dengan p-dimetilaminobenzaldehida membentuk 2-[(E)-2-[4-(dimetilamino)fenil]etenil]-6-nitro-3,4-dihidrokuinazolin-4-on, dan reduksi membentuk 6-amino-2-[(E)-2-[4-(dimetilamino)fenil]etenil]-3,4-dihidrokuinazolin-4-on. Struktur molekul senyawa produk tahap satu dan dua dikonfirmasi dengan spektroskopi FT-IR. Struktur molekul senyawa produk tahap tiga dan empat dikonfirmasi dengan spektroskopi FT-IR dan 1H-NMR. Hasil penelitian menunjukkan bahwa senyawa produk sesuai dengan senyawa yang diharapkan dengan rendemen sebagai berikut: tahap satu 90,2 %, tahap dua 79,61 %, tahap tiga 73,27 %, dan tahap empat 56,69 %.

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Derivatives of quinazolin-4(3H)-one are known to have broad pharmacological activities. The 2-styrylquinazolin-4(3H)-one is known for its inhibition activity of tubulin polymerization, epidermal growth factor receptor, and dihydrofolate reductase which play important roles on tumor development. In this research, the novel 2-styrylquinazolinone substituted on C6 position derivative, 6-amino-2-[(E)-2-[4-(dimethylamino)phenyl]ethenyl]-3,4-dihydroqui-nazolin-4-one was synthesized in four steps: formation of 2-methylquinazolin-4(3H)-one, nitration to form 2-methyl-6-nitroquinazolin-4(3H)-one, further reaction with p-dimethylaminobenzaldehyde yielding 2-[(E)-2-[4-(dimethyl-amino)phenyl]ethenyl]-6-nitro-3,4-dihydroquinazolin-4-one, and reduction to 6-amino-2-[(E)-2-[4-(dimethylamino)phenyl]ethenyl]-3,4-dihydroquinazolin-4-one. Molecular structures of first and second reaction products were confirmed with FT-IR spectroscopy. Molecular structures of third and fourth reaction products were confirmed with FT-IR and 1H-NMR spectroscopy. Results show that molecular structures of the products meet the predicted structure, with reaction yields as follow: first step 90,2 %, second step 79,61 %, third step 73,27 %, and fourth step 56,69 %."