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"This paper presents an investigation on the method for synthesizing hematite nanoparticle using ultrasonic sonochemistry. The effect of various bases with different basicity strengths, i.e. NaOH, NH4OH, and butylamine, as well as sintering treatment on the purity and crystallinity of hematite nanoparticles was studied. In this work, the as-synthesized hematite nanoparticles were characterized using FTIR, XRD, and HR-TEM analyses. The results showed that the formation of hematite crystal can undergo two possible reaction pathways depending on the basicity of the solution. When strong bases like NaOH and butylamine were used, iron(III) ion could react with water to form iron complexes, which further grow into rod-like magnetite nanocrystals as the major product. However, direct reaction of iron(III) ion with hydroxide ion to form hematite was observed when a weak base like NH4OH was used. Furthermore, it was also found that most of the polymorphous iron oxide precursors can be transformed into hematite crystals via high-temperature sintering."

"Saat ini, metode pengujian kandungan 3- Monochloropropanediol (3-MCPD) yang merupakan zat kontaminan pada minyak kelapa sawit dilakukan menggunakan instrumen GC-MS. Metode tersebut memerlukan prosedur yang lama dan rumit. Pengembangan nanopartikel emas dengan pengkaping Cysteine berpeluang menjadi solusi untuk mendeteksi 3-MCPD dalam waktu cepat berbasis analisis kolorimetri. Tujuan dari penelitian ini adalah untuk mengetahui kondisi optimal sintesis, ukuran, dan sensitivitas nanopartikel dalam mendeteksi 3-MCPD. Penelitian dilakukan dengan memvariasikan konsentrasi dan volume Cysteine. Variasi konsentrasi Cysteine yang digunakan adalah 0 hingga 0,5 mM, sedangkan variasi volume Cysteine yang dipakai adalah 0 hingga 2 ml. Pengujian 3-MCPD dilakukan dengan variasi konsentrasi 0 hingga 10 ppm. Selanjutnya, karakterisasi dilakukan dengan UV – Vis, FTIR, dan PSA. Sintesis yang optimal didapatkan ketika nanopartikel emas ditambahkan dengan 1 ml 0,025 mM Cysteine menghasilkan warna ruby red yang stabil hingga 24 jam. Ukuran nanopartikel didapatkan 27,1 nm dan terjadi pemutusan ikatan gugus fungsi tiol pada Cys-AuNPs. Nanopartikel emas ini berpotensi untuk dikembangkan lebih lanjut dalam mendeteksi 3-MCPD.

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Currently, the assay method of 3-Monochloropropanediol (3-MCPD) which is a contaminant in palm oil is carried out by using the GC-MS instrument. This method requires a long and complicated procedure. The development of gold nanoparticles with cysteine capping has the opportunity to be a solution to detect 3-MCPD in a fast time based on colorimetric analysis. This study aims to determine the optimal conditions for synthesis, size, and sensitivity of nanoparticles in detecting 3-MCPD. The research was conducted by varying the concentration and volume of Cysteine. Cysteine concentration variations used are 0 to 0.5 mM and the volume variation of Cysteine used is 0 to 2 ml. The 3-MCPD test was carried out with a concentration variation of 0 to 10 ppm. Furthermore, characterization was carried out using UV-Vis, FTIR, and PSA. Optimal synthesis was obtained when gold nanoparticles were added with 1 ml of 0.025 mM Cysteine. The color of the nanoparticles is ruby red and stable for up to 24 hours. The nanoparticle size was 27.1 nm, and the thiol functional group bond was broken in Cys-AuNPs. These gold nanoparticles have the potential to be further developed in detecting 3-MCPD."

"Sampel nanopartikel coupled magnetite Fe3O4/ZnO dengan tiga variasi rasio molar disintesis dengan metode sol gel. Karakterisasi sampel dilakukan dengan menggunakan Field Emission Scanning Electron Microscope (FESEM), X-ray Diffraction (XRD), Electron Dispersive X-Ray (EDX), spektroskopi UV-Vis dan Vibrating Sample Magnetometer (VSM). Pengujian aktivitas fotokalitik dilakukan dengan mengamati degradasi larutan methylene blue (MB) sebagai model polutan organik di bawah penyinaran cahaya UV. Hasil analisis FESEM menunjukkan sampel nanopartikel coupled memiliki morfologi sferis. Hasil kurva XRD menunjukkan peningkatan intensitas seiring dengan meningkatnya rasio molar ZnO dalam nanopartikel coupled Fe3O4/ZnO. Keberadaan atom Fe, O dan Zn pada sampel nanopartikel coupled dikonfirmasi oleh spektrum EDX. Aktivitas fotokalitik yang paling baik ditunjukkan oleh sampel nanopartikel coupled rasio molar 1:5 dengan dosis sebanyak 20 mg/L pada kondisi pH 13. Nanopartikel Fe3O4 dan nanopartikel coupled Fe3O4/ZnO menunjukkan sifat feromagnetik yang memungkinkan sampel untuk dipisahkan secara magnetik dari dye methylene blue.

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Nanoparticle coupled magnetite Fe3O4/ZnO with various molar ratio has been syntesized using sol gel method. Characterization using Field Emission Scannig Electron Microscope (FESEM), X-Ray Diffraction (XRD), Electron Dispersive X-ray (EDX), UV-Vis Diffuse Reflectance and Vibrating Sampel Magnetometer (VSM) were conducted to identify morphology, structure, composition, optical and magnetic properties of nanoparticle coupled Fe3O4/ZnO. Photocatalytic activity studied by observing methylene blue (MB) degradation under UV light irradiation. FESEM shows Fe3O4/ZnO has spherical shape. XRD result shows ZnO phase intensity in nanoparticle coupled increase as ZnO molar ratio increase. The peaks corresponding to Fe, O and Zn atom were observed using EDX spectra. Maximum degradation of methylene blue was showed by 20 mg/L nanoparticle coupled with molar ratio 1:5 at pH 13. VSM result shows Fe3O4 and nanoparticle coupled samples exhibit ferromagnetic behavior. Therefore, samples can easily seperate from methylene blue using external magnetic."

"ZnO nanopartikel dengan berbagai variasi konsentrasi dopan Co2+ (3, 6, 15 dan 17 at.%) disintesis dengan metode ko-presipitasi. Karakerisasi yang dilakukan meliputi pengukuran EDX, XRD dan UV-VIS untuk mengamati struktur dan sifat optis dari ZnO didop Co nanopartikel. Komposisi Co dalam sample dikatahui dari karakterisasi EDX,. Hasil difraksi sinar X (XRD) menunjukkan bahwa sampel memiliki fase wurtzite dan tidak ditemaknnya fase sekunder. Hasil tersebut membuktikan bahwa ion Co2+ telah berhasil mensubtitusi Zn2+ dalam matrix ZnO. Analisis pelebaran puncak sinar X dilakukan untuk menilai crystalline size dan lattice strain dengan menggunakan metode analisis Williamson-Hall (W-H). Seluruh parameter terkait seperti strain, stress dan nilai energy density turut ditentukan nilainya dengan menggunakan berbagai model dari analisis W-H, yakni uniform deformation model (UDM), uniform stress deformation model (USDM) dan uniform deformation energy density model (UDEDM). Ketiga model analisis tersebut akan menghasilkan nilai strain yang berbeda diakibatkan pendekatan-pendekatan yang dilakukan. Sifat optis seperti celah pita energy dikarakterisasi dengan spektroskopi UV-VIS menunjukan penurunan seiring dengan bertambahnya konsentrasi dopan yang diberikan.

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ZnO nanoparticles with different Co2+ doping concentrations (3,6,15 and 17 at.%) were synthesized by co-precipitation method. Characterization technique of EDX, XRD and UV-Visible spectra measurement were done to investigate the effects of the doping concentration on the structural and optical properties of Co doped ZnO nanoparticles (NP). The compositional analysis was carried out by Energy Dispersive X-Ray (EDX) measurement. X-Ray diffraction analysis reveals that the Co doped ZnO NP crystallize in wurzite structure without any impurity phase and Co2+ ion were successfully incorporated into the lattice position of Zn2+ ions in ZnO matrix. The wurzite structure (lattice constant) is decreasing with increasing Co doping concentration, it show their crystallization decrease with the increase of Co2+ doping Concentration. The crystalline development in the Co doped ZnO NP was investigated by X-Ray peak broadening. The Williamson-Hall (WH) analysis was used to study the individual contribution of crystallize size and lattice strain on the peak broadening. All other relevant physical parameter such as strain, stress and energy density values were also calculated using W-H plot analysis with different model, viz, uniform deformation model, uniform stress deformation model and uniform deformation energy density model, the three models yield different strain values, it may be due to anisotropic nature or the material. The optical studies show that the band gap of Co doped ZnO NP decreases with increase doping concentration."

"Pada penelitian ini, nanopartikel Li₃PO₄, Fe₃(PO₄)₂, LiFePO₄ sampel A telah berhasil disintesis menggunakan ekstrak daun delima (Punica granatum L) dengan metode green synthesis dan nanopartikel LiFePO₄ sampel B telah berhasil disintesis dengan metode kimia (sol-gel). Ekstrak daun delima (EDD) yang dihasilkan mengandung senyawa metabolit sekunder yang berfungsi sebagai sumber basa dan capping agent dalam menstabilkan ukuran nanopartikel dan mencegah terjadinya proses aglomerasi. Hasil karakterisasi FTIR menunjukkan bahwa LiFePO₄ sampel A dan B membentuk serapan vibrasi (v₂-v₄) PO₄^3- pada bilangan gelombang 586 cm^-1 - 461 cm^-1 (v₄ & v₂) dan 1038/1035 cm^-1 (v₃). Pada hasil XRD menunjukkan nanopartikel LiFePO₄ sampel A dan B memiliki sistem kristal orthorombik. Hasil SEM menunjukkan morfologi LiFePO₄ memiliki bentuk yang heterogen. Nanopartikel LiFePO₄ yang telah disintesis kemudian dijadikan sebagai lembaran katoda dan disusun menjadi baterai ion litium kemudian dilakukan karakterisasi elektrokimia menggunakan EIS, CV dan GCD. Hasil uji GCD menunjukkan bahwa sampel A memiliki kapasitas discharge sebesar 0,35 mAH/gram sedangkan sampel B memiliki kapasitas discharge sebesar 0,93 mAH/gram.

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In this research, Li₃PO₄, Fe₃(PO₄)₂, LiFePO₄ nanoparticles sample A have been successfully synthesized using pomegranate leaf extract (Punica granatum L) with green synthesis method and LiFePO₄ nanoparticle sample B have also been successfully synthesized by chemical method (sol-gel). Pomegranate leaf extract (EDD) produced contains secondary metabolite compounds that function as a source of base and capping agent in stabilizing the size of nanoparticles and preventing agglomeration. The results of FTIR characterization shows that the LiFePO₄ nanoparticles of samples A and B forms vibrational absorption (v₂-v₄) PO₄^3- at wavenumbers 586-461 cm^-1 (v₄ & v₂) and 1038/1035 cm^-1 (v₃). The XRD results show that the LiFePO₄ nanoparticles of samples A and B have an orthorhombic crystal system. SEM results show that the morphology of LiFePO₄ has a heterogeneous shape. The LiFePO₄ nanoparticles that were formed were successfully used as cathode sheets and arranged into lithium ion batteries then electrochemical characterization was carried out using EIS, CV and GCD. The GCD test results show that sample A has a discharge capacity of 0,35 mAH/gram while sample B has a discharge capacity of 0,93 mAH/gram."

"Penelitian bertujuan mempelajari pembentukan nanopartikel 𝐵𝑎0.5𝑆𝑟0.5𝑇𝑖𝑂3 (B50ST) melalui sintesis pemaduan mekanik dan destruksi ultrasonik. Semua prekursor dari B50ST dipadukan secara mekanik menggunakan planetary ball mill serta di sintering untuk reaksi solid-state. Tahapan sintesis menghasilkan partikel kristalin berfasa tunggal dengan ukuran rata-rata sebesar 1738 nm. Kemudian partikel kristalin didispersikan kedalam air demin dalam 3 konsentrasi berbeda masing masing 0,67; 2 dan 3 %. Partikel dalam media menjalani proses destruksi ultrasonik dalam 4 durasi waktu yang berbeda masing-masing 1, 3, 5 dan 9 jam. Hasil evaluasi ukuran partikel menunjukkan bahwa destruksi ultrasonik terhadap partikel dalam media sangat efektif mengecilkan ukuran partikel. Dalam durasi destruksi selama 1 jam terhadap media dengan konsentrasi 0,67 % mampu menurunkan ukuran rata-rata partikel menjadi 789 nm dan menjadi lebih halus lagi mencapai ukuran rata-rata partikel 220 nm pasca destruksi 9 jam dan dengan distribusi ukuran yang sangat sempit mengindikasikan ukuran partikel yang hampir seragam. Hal yang mirip juga ditemukan pada hasil proses destruksi media konsentrasi yang lebih besar, namun ukuran partikel rata-rata diperoleh meningkat dengan meningkatnya konsentrasi partikel. Berbeda dengan hasil evaluasi ukuran partikel, maka ukuran kristalit dalam partikel pasca tahapan destruksi ultrasonik tidak mengalami perubahan ukuran sebesar ~34 nm yaitu hampir sama dengan ukuran kristalit partikel sebelum tahapan destruksi. Penelitian ini menyimpulkan bahwa nanopartikel dapat dihasilkan melalui proses sintesis melalui pemaduan mekanik dan dilanjutkan dengan destruksi ultrasonik. Semakin rendah konsentrasi partikel dalam media, semakin halus ukuran partikel yang dihasilkan. Semakin panjang durasi waktu destruksi ultrasonik, semakin halus ukuran partikel yang diperoleh. Partikel berukuran rata rata 220 nm atau kira-kira 7 kali ukuran kristalitnya telah diperoleh dalam penelitian ini.

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We reported results of research studies regarding the formation of (B50ST) nanoparticles synthesized through mechanical alloying followed by ultrasonic destruction. All precursors of B50ST were mechanically alloyed under a planetary ball mill and successively sintered for a solid state reaction. These has resulted in single phase crystalline particles with an average size of 1738 nm. The crystalline particles were then dispersed into a demineralized water media in 3 different solution concentrations respectively 0.67; 2 and 3%. Particles in each solution were then subsequently undergo ultrasonic destruction process in four different time duration respectively 1, 3, 5 and 9 hours.

Results of particle sizes evaluation showed that the ultrasonic destruction very effective to reduce the particle size. In destruction of over 1 hour duration, the average size of the particles in the solution of 0.67% was drastically refined to 789 nm and further refined to 220 nm after the destruction of 9 hours. In addition, the particle size distribution was very narrow indicating nearly uniform particle sizes. A similar case was found in greater media concentrations, but the average particle size obtained was increased with increasing the particle concentration. In contrast to results of particle size evaluation, crystallite sizes evaluation for refined particles showed no significant changing in which the size of ~ 34 nm which is almost equal to the crystallite size of the particles before the stages of destruction.

The study concluded that the nanoparticles can be produced through synthesis process of crystalline particles by mechanical alloying process and successively followed by ultrasonic destruction. The lower the concentration of particles in the media, the finer the particle size produced. The longer the duration of the ultrasonic destruction, the finer the particle size obtained. The average particle size of 220 nm or about 7 times the size of its crystallite size has been obtained in this study."

"Nanozeolite synthesis was carried out through seeding method, in which the seed was Y zeolite (member of faujasite, FAU, family) using tetraethyl orto silicate (TEOS) as silica source, and aluminium isopropoxide Al[(CH3)2CHO)]3 as aluminum source, and tetramethylammoniumhydroxide (TMAOH) as template, under hydrothermal condition. The seeds then were grown on glassy carbon (GC) sheet, that prior being used was modified, using layer by layer (LbL) technique, with three layers of polyelectrolytes: Poly(diallyldimethylammoniumchloride), PDDA; Poly-4-sodium-styrenesulfonate, PSS; and PDDA again. The seeded GC sheet then was immersed into colloidal suspension with molar composition as follow: 14Na2O: Al2O3: 10SiO2: 798H2O: 3Na2SO4 and the pH of the suspension was kept at 9,0 before was treated hydrothermally for 20 hours at 100oC. The variation on number of seed layers on GC (1, 2 and 3 layers), observed by SEM, showed that homogenous structure and crystal size was obtained with 1 layer of seeds applied on the surface of glassy carbon. When more layers of seeds applied, the agregation and intergrowth of zeolite crystals in the thin film of zeolite became more visible. XRD pattern of the as-prepared thin film zeolite indicates that the zeolite has nanoparticle structure. Furthermore, the pattern of glassy carbon predominated the XRD pattern and covered the pattern of Y-zeolite. On the other hand, XRD of as prepared bulk Y-zeolite shows structure of FAU framework."

"Sintesis material ferroelektrik SrTiO3 (STO) dan material magnet SrFe12O19 (SHF) melalui teknik pemaduan mekanik dilanjutkan perlakuan sintering pada temperatur 1100°C selama 3 jam. Kedua material sudah berfasa tunggal berdasarkan hasil identifikasi puncak-puncak difraksi sinar-x pada masing-masing pola difraksi. Ukuran partikel material STO dan SHF masing-masing adalah 1116 nm dan 1230 nm. Destruksi partikel secara ultrasonik selama 7 jam, memperkecil ukuran rata-rata partikel dari kedua senyawa menjadi 522 nm dan 70 nm. Teknik destruksi secara mekanik dan ultrasonik dapat digunakan untuk pembentukan nanopartikel.

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Synthesis of ferroelectric material SrTiO3 (STO) and magnetic material SrFe12O19 (SHF) with mechanical alloying method and sintering with temperature at 1100°C for 3 hours. Both of the material have been a single phase based on the identification result of the peaks in each diffraction pattern. The particle size of material STO and SHF is 1116 nm and 1230 nm. Ultrasonic destruction for 7 hours reduced the mean particle size for both material to 522 nm and 70 nm. Particle destruction with mechanical and ultrasonic method can be used to synthesis of nanoparticle."

"Tanaman melinjo (Gnetum gnemon L.) yang tumbuh banyak di Indonesia, diketahui memiliki biji dengan kandungan trans-resveratrol cukup tinggi dibandingkan anggur. Trans-resveratrol merupakan senyawa polifenol, yang strukturnya mengandung gugus fenol dan cincin benzene dengan gugus hidroksi. Microwave assisted extraction (MAE) merupakan metode ekstraksi yang dapat digunakan sebagai metode alternatif terhadap metode ekstraksi konvensional karena dengan metode MAE proses ekstraksi berjalan lebih singkat dan menggunakan pelarut yang lebih sedikit. Penelitian ini bertujuan untuk mengoptimalkan proses ekstraksi MAE dari biji melinjo sehingga mendapatkan formulasi sediaan yang kaya kandungan trans-resveratrol dan mampu berpenetrasi dengan baik di kulit. Pada penelitian ini optimasi ekstraksi dilakukan dengan metode MAE menggunakan dua pelarut. Pembuatan solid lipid nanoparticles (SLN) menggunakan metode homogenisasi tekanan tinggi dan potensi penetrasi sediaan diuji dengan metode sel difusi Franz. Dari optimasi ekstraksi MAE diperoleh kadar trans-resveratrol tertinggi adalah menggunakan pelarut [Bmim]Br dengan kadar 0,52 mg/g simplisia yang diekstraksi selama 10 menit dan daya gelombang mikro sebesar 10%, sedangkan kadar trans-resveratrol dari fase etil asetat biji melinjo adalah 3,3 mg/g ekstrak. Jumlah kumulatif terpenetrasi trans-resveratrol dari fase etil asetat biji melinjo dalam gel SLN adalah 19,8±0,42 μg/cm2 dengan nilai fluks 1,45±0,04 μg/cm2/jam, sedangkan untuk gel non SLN hanya mencapai 7,7±0,13 μg/cm2 dengan nilai fluks 0,36±0,02 μg/cm2/jam. Penelitian ini menunjukkan bahwa fase etil asetat biji melinjo yang diformulasikan dalam sediaan gel SLN memiliki kemampuan penetrasi di kulit yang lebih baik dibandingkan sediaan gel non SLN.

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Melinjo (Gnetum gnemon L.) plant that grows in many area of Indonesia, is known to have seeds with trans-resveratrol content is quite high compared to wine. Trans-resveratrol is a polyphenol compound, whose structure contains a phenol group and a benzene ring with a hydroxy group. Microwave assisted extraction (MAE) is an extraction method that can be used as an alternative method to conventional because MAE extraction could run shorter and uses less solvent. This study aims to optimize the extraction process of MAE from melinjo seeds so as to get the formulation rich in trans-resveratrol and able to penetrate through the skin. In this study, the optimization of extraction was done by MAE method using two solvents. Preparation of solid lipid nanoparticle (SLN) using high pressure homogenization method and the potential penetration of gel SLN was tested by cell diffusion Franz method. From the optimization of MAE extraction, the highest trans-resveratrol obtained was 0.52 mg/g dry weight using 2.5 M [Bmim]Br extracted for 10 minutes and 10% of microwave power, while the ethyl acetate phase obtained was 3.3 mg/g extract. The cumulative amount of trans-resveratrol penetration of the melinjo seed ethyl acetate phase in the SLN gel was 19.8±0.42 μg/cm2 with a flux value of 1.45±0.04 μg/cm2/hr, while for non-SLN gel only reached 7,7±0.13 μg/cm2 with a flux value of 0.36±0.02 μg/cm2/hr. This study shows that the ethyl acetate fraction of melinjo seed formulated in SLN gel preparations has better skin penetration ability than non-SLN gel."

"Aditif Nanopartikel CaCO3 dapat meningkatkan daya guna pada gemuk seperti anti aus, dan koefisien friksi, serta aditif tersebut bersifat ramah lingkungan dan tidak beracun. Sintesis gemuk bio NLGI 2 dilakukan dengan reaksi saponifikasi dengan minyak sawit sebagai base oil-nya dan asam oleat epoksida, asam asetat serta kalsium hidroksida sebagai pengentalnya. Preparasi Nanopartikel CaCO3 dengan metode presipitasi melalui rute karbonasi menghasilkan ukuran nanopartikel sebesar 70-90 nm. Nanopartikel CaCO3 digunakan sebagai aditif gemuk bio dengan variasi komposisi 0-10% berat. Penggunan aditif nanopartikel CaCO3 dapat mengurangi jumlah keausan dan memiliki titik optimum yakni saat konsentrasi aditif sebesar 5% dengan jumlah keausan 0,8 mg dan dropping point 2810 C.

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Additives CaCO3 nanoparticles can increase the usability of the Grease as anti-wear and coefficient of friction, and the additives are environmentally friendly and non-toxic. Synthesis bio grease NLGI 2 carried out by saponification reaction with palm oil as its base oil and oleic acid epoxide, acetic acid and calcium hydroxide as Thickener. Preparation of CaCO3 nanoparticles by precipitation method through the carbonation route, produce nanoparticles of 70-90 nm size. CaCO3 nanoparticles used as additives with bio grease composition variation of 0-10% by weight. Use of additives CaCO3 nanoparticles can reduce the amount of wear and have the optimum point when additive concentration of 5% and the amount of wear with the 0.8 mg and dropping point 2810 C."