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Abstrak :
Telah dilakukan penelitian pada paduan La0.67Ba0.33Mn1-xTixO3 dengan variasi x=0; 0.02; 0.04; 0.06 dengan mensintesa dan mengkarakterisasi bahan tersebut. Sintesa dilakukan menggunakan metode mechanical alloying dengan mencampurkan bahan-bahan dasar penyusun yakni La2O3, BaCO3, MnCO3, dan TiO2. Campuran ini kemudian dimilling selama 10 jam kemudian dikarakterisasi menggunakan Thermogravimetry Analysis (TGA). Kemudian dilakukan proses kalsinasi pada suhu 800º C selama 8 jam dan dilanjutkan dengan proses sintering pada suhu 1100º C selama 12 jam. Karakterisasi lainnya menggunakan difraksi sinar-X (XRD) sebelum sintering dan setelah sintering yang menunjukkan paduan La0.67Ba0.33Mn1-xTixO3 telah memiliki fasa tunggal dengan sistem kristal monoklinik,dengan parameter kisi a=5.53 Å ; b=5.54 Å ; c=7.8 Å dan space group I 1 2/c 1 (15), Particle Size Analyzer (PSA) menunjukkan hasil ukuran partikel besar untuk sampel yang tidak disintering. Scanning Electron Microscopy (SEM) untuk melihat morfologi permukaan. Hasil ukuran kristalit rata-rata menggunakan metode Debye-Scherrer.menghasilkan ukuran kristalit rata-rata material LBMO sebesar 60.3 nm dan LBMTO untuk setiap variasi x sebesar `~78.8 nm. ......This research focuses on the mixture La0.67Ba0.33Mn1-xTixO3with the value x=0; 0.02; 0.04; 0.06. The x variation is done through synthesis and characterizing the sample. The method of synthesis is mechanical alloying, by mixing the basic compounds La2O3, BaCO3, MnCO3 with TiO2. The milling process of this mixture is 10 hours, then characterized using Thermogravimetry Analysis (TGA). Then, calcination at 800º C for 8 hours followed by sintering at 1100º C for 12 hours. XRD is done, in addition, before and after sintering. Results show the mixture La0.67Ba0.33Mn1-xTixO3have a single phase monoclinic crystal structure with cell parameter a=5.53 Å ; b=5.54 Å ; c=7.8 Åand space group I 1 2/c 1 (15). PSA shows big particles for samples not undergoing sintering. SEM is used to analyze the surface morphology. The Debye-Scherrer method calculates the average resulting crystallites, with values LBMO = 60.3nm and for LBMTO = 78.8nm (for each x variation).

Abstrak :
The synthesis and characterization of nickel-graphite (Ni-C) nanocomposite materials by mechanical milling method have been performed. This composite was prepared by mixing high purity nickel and graphite. The mixture was milled for 25, 50, and 75 hours and then was compacted at pressure of 5000 psi. The samples consist of two phases, namely carbon and nickel phases. Carbon phase has hexagonal structure, space group: P 63 m c (186), lattice parameters of a = b = 2.352(1) Å and c = 6.669(7) Å, ? = ? = 90o and g = 120o, V = 31.9(7) Å3 and r = 5.585 gr.cm-3. Nickel phase has cubic structure, space group: F m -3 m (225), lattice parameters of a = b = c = 3.5254(7) Å, ? = ? = g = 90o, V = 43.81(2) Å3 and r = 8.898 gr.cm-3. The calculation results show that the crystallite size of the Ni-C75 sample was around 3.83 nm. The Ni-C75 sample is also suspected to have grown embryo of carbon nanotube (CNT) due to the presence of nickel. The hysteresis loop of the sample consists of intrinsic saturation Ms, remanence Mr, and coercivity Hc are 1.40 emu/gr, 0.28 emu/gr, and 128 Oe, respectively. The value of MR is about 28% at 7.5 kOe magnetic field. The sample shows magnetoresistance behavior and the phenomenon of sensor characteristics. We concluded that this study has successfully made Ni-C nanocomposite and it is expected that the nano composite Ni-C is able to be used for sensor material application.

Abstrak :
The purpose of this experiment is to study the influence of 10% carbomide peroxyde and 0.4% stannous fluoride application on the crystallic of hydroxypatite in tooth enamel, by using x-ray diffraction method. Hydrogen peroxide solution and distilled water are used as control. The materials are applied for X hours in an incubator with 37"C and 100% humidity, for total 192 hours. The crystallite size and the lattice parameters are calculated from x-ray diffraction pattern, and the structure was then refined by Rieiveld analysis. lt can he concluded that carbamide pcroxyde and stannous fluoride do not influence neither the crystallic size of tooth enamel nor the lattice parameters, but they influence the micro strain in crystal. The X-ray diffraction on Ihc facial surface of enamel shows preferred orientation pattern at |002].

Abstrak :
Zinc Oxide (ZnO) is an important semiconductor material due to its broad applications, such as in the fields of electronics, optoelectronics, photocatalysts, and solar cells. The main purpose of this work was to investigate the effect of pressure in post-hydrothermal treatment on crystallinity enhancement, crystallite growth, and band gap reduction of ZnO nanoparticles, which could be expected to improve their performance as the semiconductor oxide layer in the dye-sensitized solar cell application. For this purpose, ZnO nanoparticles have been successfully synthesized through the precipitation method, followed by a sequence of thermal treatments including drying, calcination, and Post-hydrothermal Treatment (PHT). For increasing the crystallinity of ZnO nanoparticles, PHT was carried out with a pressure variation of 1 and 3 bar. The resulting nanoparticles were further characterized with X-Ray Diffraction (XRD), Ultra-Violet Visible (UV-Vis) spectroscopy and a Scanning Electron Microscope (SEM). The study showed that by increasing the PHT pressure from 1 to 3 bar caused an adverse effect on the crystallinity, i.e. the crystallite size of ZnO nanoparticles slightly decreased from 27.42 to 26.88 nm. This was expected to be due to the increase of the boiling point of water causing less effective of vapor generated to improve the crystallinity by a cleavage mechanism on the inorganic framework. The band gap energy (Eg), however, was found to increase slightly from 3.25 to 3.26 eV, respectively. Considering the obtained properties, ZnO nanoparticles in this study have the potential to be used as the semiconductor oxide layer in the dye-sensitized solar cells.

Abstrak :
ABSTRAK
Nanostruktur TiO2 sebagai semikonduktor memiliki sifat-sifat unggul yang menjadikannya menarik untuk diteliti dan dikembangkan hingga sekarang. Sintesis dari nanostruktur TiO2 telah dilakukan pada penelitian ini dengan teknik presipitasi menggunakan prekursor TiOSO4.xH2O dan template kombinasi surfaktan P123 dan CTAB. Variabel yang diteliti berupa jenis pelarut yang digunakan untuk membuat larutan precursor (air dan ethanol), perlakuan hidrotermal, dan temperatur kalsinasi (200 dan 400 oC) yang bertujuan untuk menginvestigasi pengaruhnya terhadap kristalinitas fasa dan ukuran kristalit dari nanostruktur TiO2 yang dihasilkan. Karakterisasi dilakukan menggunakan XRD, TEM, dan UV-Vis. Hasil yang didapatkan menunjukkan parameter terbaik dalam sintesis nanostruktur TiO2 adalah dengan menggunakan pelarut air suling dalam pembuatan larutan prekursor, perlakuan hidrotermal untuk metode sintesisnya, dan temperatur kalsinasi 400 oC dimana didapatkan nanostruktur TiO2 dengan fasa anatase yang memiliki ukuran kristalit mencapai 8,02 nm. Hasil nanostruktur yang diperoleh ini menjanjikan untuk dipakai dalam aplikasi sel surya tersensitasi zat pewarna dan fotokatalisis.

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ABSTRACT
TiO2 nanostructure as semiconductor has distinguished properties that makes this material attractive to be studied and developed up until now. In this study, synthesize of TiO2 nanostructure was carried out by precipitation technique, using TiOSO4.xH2O as precursor and combination of P123 and CTAB surfactant as template. Variables investigated were solvent for preparing precursor solution (distilled water and ethanol), hydrothermal treatment, and calcination temperature (200 and 400 oC), which were aimed to investigate their effects of phase cristallinity and crystallite size of TiO2 nanostructure. Characterizations were performed by using XRD, TEM, and FTIR. The results showed that the best parameters in synthesizing TiO2 nanostructure are by using distilled water as solvent for preparing precursor solution, hydrothermal treatment for the synthesize method, and calcination temperature of 400 oC which successfully obtained nanostructure TiO2 with anatase phase and its crystallite size reached 8,02 nm. The obtained TiO2 nanostructure promises to be used in dye sensitized solar cell and photocatalytic applications.

Abstrak :
Telah dilakukan penelitian untuk membuat paduan Sn-Cu-Zn dengan menggunakan material solder 99.3% Sn - 0.7% Cu (wt%) dan plat Zn. Pembuatan material menggunakan metode peleburan dengan lima buah sampel dengan variasi komposisi Zn. Karakterisasi XRD digunakan untuk melihat sifat struktural, fasa yang terbentuk, ukuran kristal serta regangan mikro. Metode perhitungan ukuran kristal dan regangan mikro menggunakan metode Scherrer dan metode Williamsons-Hall. Dari hasil penelitian didapatkan bahwa besar parameter kisi akan berubah saat besar konsentrasi Zn ditambahkan juga, walaupun besar perubahan tersebut tidak signifikan. Ukuran kristal terbesar didapatkan pada 12.9 wt% Zn, saat besar konsentrasi Zn ditambahkan maka ukuran kristal serta regangan mikro akan menurun. Pada paduan Sn-Cu-Zn ini hanya ditemukan 3 buah fasa yaitu fasa Sn (Timah), fasa Cu (Tembaga) dan fasa Zn (Seng). ......Research on creating Sn-Cu-Zn alloys consisting solder material 99.3% Sn - 0.7% Cu (wt%) and Zn plate has been done. The alloy were manufactured using fusion method with five various Zn composition. XRD characterization was used to observe the structural properties, type of phase, crystallite size and microstrain. Scherrer and Williamson-Hall method was used to calculate crystallite size and microstrain. The result shown that lattice parameter changed when Zn concentration changed, with no significant variation of change. The largest crystallite size were found with 12.9 wt% Zn, and when the Zn composition was increased the crystallite size and microstrain will decrease. Only 3 phase were found in Sn-Cu-Zn alloys, the phases is Sn (Stannum), Cu (Cuprum) and Zn (Zinc).

Abstrak :
Pada penelitian ini, telah dilakukan sintesis nanopartikel TiO2 melalu proses sol─gel dengan variasi rasio air terhadap prekursor (Rw) yaitu 0.85, 2.00 dan 3.50 selama proses formulasi yang kemudian diikuti perlakukan termal lanjut berupa pengeringan, anil dan pasca-hidrotermal. Karakterisasi XRD dilakukan untuk mengukur besar ukuran kristalit nanopartikel yang dihasilkan. Dari hasil perhitungan, metode pasca-hidrotermal menghasilkan produk dengan ukuran kristalit paling tinggi dibandingkan perlakukan anil dan pengeringan. Ukuran kristalit tertinggi dimiliki sampel Rw = 3.50 cair dengan besar ukuran kristalit 8,566 nm, diikuti Rw = 3.50 gel sebesar 7,614 nm, Rw = 2.00 sebesar 6,853 nm dan Rw = 0.85 sebesar 6,527 nm. Lebih jauh lagi, nanotube TiO2 difabrikasi melalui teknik hidrotermal dengan melarutkan nanopartikel TiO2 hasil perlakuan anil dan serbuk P-25 Degussa ke dalam larutan alkalin sodium hidroksida berkonsentrasi tinggi di dalam otoklaf tersegel. Detil struktur dan morfologi sampel diuji dengan SEM. Hasil investigasi menunjukkan bahwa nanopartikel dengan Rw = 2.00 berhasil dibuat menjadi nanotube dengan diameter 115─269 nm.

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In this study, TiO2 nanoparticles was synthesized via sol−gel process with various water to inorganic precursor ratio (Rw) of 0.85, 2.00 and 3.50 upon sol preparation, followed with subsequent drying, conventional annealing and posthydrothermal treatments. The resulting nanoparticles were characterized using XRD to measure the crystallite size. On the basis of results obtained, the posthydrothermal resulted TiO2 samples with largest crystallite size in comparison to drying and annealing. The largest crystallite size of hydrothermally treated samples is Rw = 3.50 cair with 8,566 nm, followed by Rw = 3.50 gel with 7,614 nm, Rw = 2.00 with 6,853 nm and Rw = 0.85 with 6,527 nm. Furthermore, nanotube TiO2 have been fabricated through a hydrothermal technique where anneal treated nanopartikel TiO2 sol-gel and P-25 Degussa nanopowder was dissolved in highly concentrated alkaline solution of sodium hydroxide (NaOH) in a sealed autoclave. The detail of the structure and morphology of the resulting nanotubes were characterized using SEM. The result of investigation showed that nanoparticle with Rw = 2.00 can be fabricated became nanotubes with its diameter 155─269 nm.

Abstrak :
This investigation presents the synthesis procedure and the results of an investigation of the crystallite growth of TiO2 and the formation of Si–O–Ti bonds in novel silica xerogel (SiO2) glass ceramic produced from an amorphous SX derived from sago waste ash. The composition had been prepared by adding various amounts of TiO2, from 20 wt% to 80 wt%, into the amorphous SiO2, and then a series of samples were sintered at 1200°C for 2 hours. The influence of the content of TiO2 and the sintering temperature on the properties of TiO2, namely crystallite size and formation of Si–O–Ti bonds, has been studied in detail. The properties of the produced ceramics have been characterized on the basis of the experimental data obtained using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. It has been found that an addition of SiO2 confers an appreciable effect on the quantity of Si–O–Ti bonds. The interpretation of the XRD pattern allows one to explain the increase in the crystallite size of rutile TiO2 by a decreased quantity of Si–O–Ti bonds.

Abstrak :
Among semiconductors, zinc oxide (ZnO) has received great attention due to its wide band-gap and high electron mobility, resulting in various strategic applications. Controlling the physical properties of ZnO is therefore a critical issue in the fabrication of related electronic and optical devices. In this study, ZnO nanorods layers were grown on an ITO glass substrate via chemical bath deposition at low temperature. Prior to the growing process, the layers were deposited using a spin-coating technique. The seeding solution was made by dissolving zinc nitrate tetrahydrate and hexamethylene tetraamine in cold water (0oC) for an hour using a cooler bath. The as-synthesized ZnOs were further subjected to different post-hydrothermal treatment series at a temperature of 150oC for three hours at atmospheric pressure and at 100°C for one hour under one bar of nitrogen gas (N2) pressure. The characterization was performed using scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and UV-Vis spectroscopy. The SEM results showed that the ZnO nanorods were grown as a vertically aligned hexagonal structure, while the XRD patterns showed a high intensity at the (002) plane. On the basis of investigation, it was found that under post-hydrothermal treatment at 150oC for three hours with atmospheric pressure, the synthesis procedure resulted in nanostructures in the form of ZnO rods. Meanwhile, post-hydrothermal treatment at 100°C for one hour under one bar of nitrogen gas (N2) produced ZnO rods and tubes. In general, the post-hydrothermal process provided a high degree of crystallinity. The optimum ZnO layer was obtained after post-hydrothermal treatment at 150oC for three hours at atmospheric pressure, with a crystallite size and band-gap energy of ~18 nm and 3.20 eV, respectively.

Abstrak :
Pengaruh variasi persen berat Bi di dalam sistem material Sn-Cu-Bi dan pemberian tekanan pada material solder SnCu terhadap parameter kisi dan ukuran kristal masing-masing sampel material telah diteliti dalam penelitian ini. Material Sn-Cu-Bi yang digunakan memiliki 5 komposisi berbeda dengan variasi persen berat Bi antara 1.2 % hingga 12%. Material SnCu yang digunakan memiliki komposisi 99.3Sn-0.7Cu kemudian diberikan variasi tekanan 5-15ton. Semua material yang digunakan dipreparasi dengan metode solid solution dengan teknik peleburan. Karakterisasi XRD digunakan untuk melihat sifat struktural, fasa yang terbentuk, ukuran kristal serta regangan mikro masing-masing sampel tiap material. Untuk material Sn-Cu-Bi, hasil refinement data XRD menggunakan metode Le Bail menunjukan bahwa pada komposisi Sn-Cu-Bi dengan persen berat Bi kurang dari 3% membentuk suatu paduan dengan satu fasa Sn. Untuk persen berat Bi lebih dari 6% campuran Sn-Cu-Bi membentuk campuran yang memiliki 2 fasa yaitu fasa Sn dan Bi. Parameter kisi dan ukuran kristal pada sistem material Sn-Cu-Bi berubah seiring dengan bertambahnya persen berat Bi dalam campuran. Untuk material paduan SnCu, pemberian tekanan pada material tersebut memberikan pengaruh pada hasil data XRD tiap-tiap material. Hasil XRD menunjukan penambahan tekanan memberikan pengaruh pada pergeseran puncak difraksi dan pelebaran puncak difraksi. Gambaran paling jelas terlihat pada puncak difraksi bidang 112. Pelebaran dan pergeseran puncak difraksi itu menunjukan pengaruh pada ukuran dan regangan mikro kristal. ......In this research, efffects of weight percent of Bi (Bismuth) variations and various pressure addition on the lattice parameter and crystallite size of Sn-Cu-Bi and Sn-Cu material system was investigated. Sn-Cu-Bi alloys and Sn-Cu alloys were manufactured using fusion solid solution method with five various composition SnCuBi and pressure addition about 5-15 ton on Sn-Cu alloy. XRD characterization was used to observe the structural properties, type of phase, crystallite size and microstrain. For material Sn-Cu-Bi, refinement XRD data pattern result using Le Bail method shown that material SnCuBi that consist weight percent Bi lower than 3%, formed an alloy with single phase, Sn. For material SnCuBi that consist weight percent Bi upper than 6.5%, mix material that has 2 phase, Sn and Bi phase was formed. Based on refinement XRD data pattern result, lattice parameter Changde along with the change of Bi concentration. The crystallite size and microstrain would change when the Bi composition increased. For SnCu alloys,the various pressure that was applied to materials could change the XRD pattern. The XRD?s result shown that diffraction?s peaks pattern become broader. The clearest figure about broadener peaks pattern was shown by diffraction?s peak plane 112 (Sn phase).