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"Telah dilakukan sintesa dan karakterisasi bahan yang memiliki formula LaMgxMn1-xO3 (x = 0; 0,15; 0,25; 0,35 dan 0,50) menggunakan metode fine ceramics dari bahan-bahan MgO, MnO2, dan La2O3 melalui perhitungan stoikiometri. Ketiga bahan tersebut dicampur dan dihaluskan dengan alat High Energy Milling pada variasi waktu 5, 8 dan 10 jam, kemudian dipanaskan pada suhu 1300oC selama 6 jam, dilanjutkan dengan proses dengan variasi waktu milling 5, 8 dan 10 jam, setelah itu dilakukan pemanasan ulang pada suhu 1100oC selama 24 jam. Seluruh bahan dasar dan setiap hasil proses dikarakterisasi dengan XRD untuk melihat evolusi fasa yang terjadi. Didapati fasa baru terbentuk setelah dilakukan pemanasan pertama. Proses milling yang makin lama ternyata memperkecil ukuran butir. Konsentrasi Mg yang makin meningkat juga ternyata turut memperkecil ukuran butir namun tidak dapat secara langsung dikorelasikan karena faktor dimensi antara ukuran butir dan parameter kisi sekitar sepuluh berbanding satu dalam diameter. Refine struktur kristal yang dilakukan dengan software GSAS menunjukan bahwa parameter kisi pada struktur ortorombik berkurang dengan bertambahnya konsentrasi Mg karena ukuran jari-jari ion Mg2+ lebih kecil dari jari-jari ion Mn2+. Sampel LaMnO3, LaMg0,15Mn0,85O3, LaMg0,25Mn0,75O3, LaMg0,35Mn0,65O3 merupakan fasa tunggal dengan struktur kristal ortorombik dan LaMg0,50Mn0,50O3 mempunyai struktur kristal rombohedral (trigonal). Konsentrasi LaMg0,50Mn0,50O3 terdiri dari dua kristal perovskite (double perovskite) yang tersusun pada arah kisi c yang diperlihatkan dari ukuran kisi c yang dua kali lebih besar dibanding dengan kisi a dan b. Karakterisasi dengan SEM memperlihatkan tren yang sama dengan hasil perhitungan ukuran butiran dengan menggunakan metode Sherrer dari hasil XRD, dimana makin lama waktu miling makin kecil ukuran butirannya dan makin banyak konsentrasi Mg juga makin kecil ukuran butirannya.

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The research of crystal structure characteristic and synthesis on LaMgxMn1-xO3 ( x = 0; 0,15; 0,25; 0,35; 0,25) using MgO, MnO2 and La2O3 components reaction based on steichiometry measurement had been done. The three materials are mixed and grinded by using High Energy Milling about 5, 8 and 10 hours, then heated in 1300oC about 6 hours, continued by milling process about 5, 8 and 10 hours. After reheated in 1100oC about 24 hours, all basic materials and the result of the process are characterize by using XRD to know the phase of evolution occurred. A new phase formed after doing firstly heated. The milling process which takes much time, is believed can minimalizing grain size. The developed Mg concentration also influences minimalizing the grain size but it cannot correlated directly because of dimention factor between the size of grain and kisi parameter about 10 to 1 in differences in diameter. Refine the structure of crystal which is done by software GSAS shows that kisi parameter in Orthorombic structure decrease and Mg concentration increases as well. If happened because the size of Mg2+ radii ion is smaller than Mn2+ radii ion. Sampel LaMnO3, LaMg0,15Mn0,85O3, LaMg0,25Mn0,75O3, LaMg0,35Mn0,65O3 are single phase in Orthorombic crystal structure and LaMg0,50Mn0,50O3 has rhombohedral crystal structure (trigonal). LaMg0,50Mn0,50O3 consentration consist of double perovskite crystal which are formed in kisi c. It is shown from the size of kisi c which is bigger than kisi a nd b. Charaterizing by using SEM shows a same trend with sum of grain size by using Schere methode in XRD result. It is shown that if the longer milling process the smaller the grain size and more Mg concentration also the smaller the grain size."

"Telah dipelajari pengaruh Pb terhadap struktur kristal dan kerapatan elektron keramik Ba1_x PbxTiO3 dengan x (nominal) = 0,5. Sampel dalam percobaan ini didapat melalui sintesis metalurgi serbuk dari bahan asal BaC03, PbC03 dan TiO2, yang merupakan reagen dengan kemurnian lebih dari 99% yang tersedia secara komersial dari E-Merck. Difraktogram sinar-X yang diperoleh pada suhu kamar dianalisis menggunakan paket program kristallografi GSAS. Analisis struktur memperlihatkan bahwa kristalnya adalah Bao,7Pb0,3TiO3 dengan tipe struktur perovskife BaTiO3, grup ruang tetragonal P4mm, a = 3,943(1) A, c = 4,055(1) A, V = 63.035(63) A3, x2 = 2,115, Rp = 18,630 dan Rwp = 23,640 dengan jumlah variabel 19. Hal ini memberikan arti bahwa penambahan Pb terhadap keramik BaTiO3 tidak merubah struktur nonsentrosimetrik bahan, akan tetapi hanya sedikit berpengaruh terhadap kontraksi sumbu a dan b dan pemanjangan terhadap sumbu c. Analisis kerapatan elektron dalam bahan memperlihatkan bahwa ada konsistensi pengukuran kerapatan elektron dengan parameter struktur kalkulasi dengan ∆p max. 7.965 e A-3 dan ∆p min.-2.555 e A-3. Hasil akhir memperlihatkan bahwa, bila dibandingkan dengan barium titanat mumi yang dalam percobaan ini mempunyai kerapatan elektron p max. 115,129 e A-3 dan 112,467 a A-3 masing-masing untuk nilai observasi dan perhitungan, terjadi penambahan kerapatan elektron pada posisi ion subtitusi dengan p max. 180,069 e A-3 dan 172,105 e A-3 masing-masing untuk nilai observasi dan nilai perhitungan. Selanjutnya, pengukuran diferensial termal dari bahan Ba0,7Pbg,3TiO3 memperlihatkan bahwa kemungkinan titik lelehnya lebih rendah dari BaTiO3, sedangkan hasil pengukuran konstanta dielektrik memperlihatkan bahwa temperatur Curie dan konstanta dielektrik pada temperatur tersebut masing-masing adalah 210 °C dan 5440.

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The effect of Pb on crystallographic structure and electron density of Ba1.xPbxTi03 ceramic, where x (nominal) = 0.5, has been investigated. The samples in this study were synthesized using powder metallurgy from BaCO3, PbCO3 and TiO2, which were reagents with purity better than 99% available commercially from E-Merck. The X-ray diffractograms, which were obtained at room temperature, were refined using the crystallographic software package GSAS. Structural analysis shows that the crystal is Bao.7Pba.3TiO3 with the perovskite-type BaTiO3 structure, the space group tetragonal P4mm, a = 3.943(1) A, c = 4.055(1), V=63.035(63) A3 with 19 refined variables, the goodness of fit x2 is of 2.115 and the residual parameters Rp and Rwp are 18.630% and 23.640% respectively. These results imply that Pb has no effect on the noncentrosymmetric structural change of barium titanate except to contract a and b axis and to extend c axis. Studies on electron density show that the electron density measurements are consistent with the calculated structural parameters with max ∆p = 7.965 e A-3 and min. ∆p = -2.555 e A-3. Final results show that, as compared to that of pure BaTi03, which in this study has the value of max. p 115,129 e A'3 and 112,467 e A-3 for the observed and the calculated value respectively, there is an increasing of electron density at the substitute ion positions with max. p 180.069 e A-3 and 172,105 e A-3 for the observed and the calculated value respectively. Furthermore, differential thermal analyzer measurements on Bao.7Pba.3TiO3 show that its melting point might be lower than that of BaTiO3, while dielectric constants measurement shows that the Curie temperature and corresponding dielectric constant are 210 °C and 5440 respectively."

"ABSTRAKTelah dilakukan refinement struktur kristal zeolit Bayah dari data difraksi menggunakan program Rietan. Intensitas difraksi dari zeolit diukur dengan teknik difraksi sinar-x (XRD). Hasil terbaik dari pencocokan dan refinement pola difraksi, yang menunjukkan keberadaan dua fasa klinoptilolit dan mordenit, memberikan tingkat reliabilitas (Rwp) sebesar 11,37 % pada sampel 1 (lokasi 1) dan 10,34 % pada sampel 2 (lokasi 2). Tingginya harga ini disebabkan oleh rendahnya data statistik dan adanya puncak-puncak abnormal, yang mungkin ditimbulkan oleh proses pemurnian zeolit alam yang kurang sempurna atau tingginya mobilitas beberapa atom. Berhasil dikonfirmasikan bahwa zeolit alam berasal dari Bayah mempunyai dua fasa yaitu fasa klinoptilolit dan mordenit yang berturut-turut mempunyai simetri ruang C2/m dengan sistim kristal monoklinik dan simetri ruang Cmcm dengan sistim kristal ortorombik. Pada sampel I fraksi berat masing-masing sebesar 59,26 % untuk fasa klinoptilolit bentuk uni kation K dan 40,74 % untuk mordenit bentuk poli kation K-Na. dengan formula K6,06(A16Si30O72) 3,OH2O dan K3.10 Na5.12(Al8Si40O96). 3,04H2O. Sampel 2, fraksi berat berturutturut sebesar 33,13 % untuk fasa klinoptilolit bentuk poli kation K-Mg dan 66,87 % untuk mordenit bentuk poll kation Ca-Na dengan formula K517 Mg0,16(AI6S6O72).1,0 H2O dan Ca1,13 Na5,63 (Al8Si40096) 1,2H2O. Dominasi fasa klinoptilolit dan mordenit tiap lokasi ternyata berbeda. Adanya dua tipe gugus hydroxyl dalam struktur sangkar zeolit telah diidentifikasi dengan teknik Spektroskopi Infra Merah (FTIR). Morfologi permukaan zeolit telah diperiksa dengan Scanning Electron Miceoscope Energy Dispersive X-Ray Analyzer (SEM-EDAX). Penelitian ini dapat memberikan harapan bahwa zeolit alam Bayah dapat digunakan sebagai bahan dengan pemakaian dan pengembangan zeolit yang tepat guna.

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ABSTRACT

The crystallographic structures of Bayah zeolite have been refined using RIETAN program from the x-ray diffraction intensity data. The best refinement gives residual factor (Rwp) of 11.37% in sample 1 (first location) and 10.34 % in sample 2 (second location) which comes from poor statistics and abnormal peaks in the data. The latter might be due to the purification problem in natural zeolite process or high mobility of same atoms. This refinement suggest that this Bayah zeolit (first sample) compound crystallizes in two phases of the clinoptilolite K-form (uni-cation) with chemical formula : K6.06 (AI6Si30O72),3.0H20 type monoclinic phase (space group C21m) and mordenite K-Na-form (poly-cation) with chemical formula K3,10 Na5.12(Al8Si40O96). 3.04H20 type orthorhombic phase (space group Cmcm) with mass fraction of 59.26 % and 40.74 % respectively. Second sample compound crystallizes also in two phases of the clinoptilolite K-Mg form (poly-cation) with chemical formula : KS.17 Mgo.16(A16Si30072).1.0 H2O type monoclinic phase (space group C21m) and mordenite Ca-Na-form (poly-cation) with chemical formula : Ca13 Na5.63(AI8Si40096).1.2 H2O type orthorhombic phase (space group Cmcm) with mass fraction of 33.13 % and 66.87 % respectively. Two types of hydroxyl group in framework were identified by using Fourier Transform Infra Red (FTIR). The surface morphology was probed with Scanning Electron Microscope Energy Dispersive X-Ray Analyzer (SEM-EDAX). The results of this investigation raise hope that the Bayah natural zeolit is able to be modified and to be used effectively."

"Material Fe murni dengan tingkat kemurnian 99,9% memiliki fasa tunggal dan sistem kristal Body Centered Cubic (BCC) yang kemudian dilakukan penggerusan mekanik (Mechanical Alloying) dan penambahan serbuk SiC untuk membandingkan pengaruh ukuran kristal material dengan sifat magnetiknya. Serbuk SiC digunakan untuk membantu memperkecil ukuran kristal Fe karena nilai kekerasan yang dimiliki SiC dapat membantu menghaluskan atom-atom Fe. Karakterisasi yang dilakukan yaitu X-Ray Diffraction (XRD) dan Permagraf. XRD dilakukan untuk melihat ukuran dari partikel, densitas, dan parameter kisi pada material Fe yang sudah dilakukan penggerusan mekanik dan penambahan SiC sedangkan Permagraf dilakukan untuk melihat sifat magnetik dari ukuran kristal yang semakin kecil. Sifat magnetik suatu material menurun seiring dengan mengecilnya ukuran kristal partikel Fe.

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Pure iron materials with 99,9% purity have a single phase and Body Centered Cubic (BCC) crystal system then performed mechanical alloying and addition SiC (silicon carbide) powder to compare the effect of crystallite size on magnetic properties of iron. SiC powder used to help reduce size of crystallite of iron because hardness values from SiC can help smooth atoms of iron. Identification study of x-rays and permagraph has been characterized. X-ray Diffraction used to found crystallite size, density, and lattice parameters in iron which performed mechanical alloying and addition SiC and then permagraph used to found magnetic properties from smaller crystallite size. Magnetic properties in material decrease with smaller crystallite size."

"Telah dilakukan analisa mengenai pengaruh penambahan 0.5 inol berat Mn terhadap fasa dan Struktur kristal barium titanat (BaTiO:,). Cuplikan diperoleh dengan metoda metalurgi serbuk dengan bahan dasar BaCQ-,. MnO_, dan FiO: yang merupakan grade reagen dari E-Merck, dengan perbandingun masing-masing 1 : 0,5 : 0,5. Difraktogram sinar-X dengan A, (Co K.O.) "= 1,7889 A dan scan secara kontinu pada temperatur kamar dianalisis menggunakan program kristalografi GSAS. Analisis struktur metnperlihatkan bahwa bahan terdiri dari 5 (lima) fasa, BaMn05Ti05O3 sebagai fasa utama dengan grup ruaiig P4mm, parameter kisi a dan c masing-masing 3,999 A dan 4,025 A, faktor pencocokan (i educed x ) =- 2,175 dan 45 variabel. Sedangkan 4 (empat ) fasa pengotor tersebut masing-masing memiliki fraksi berat yaitu BaCO., (45,83%); MnO2 (8.47%); TiO: (20,36%) dan MmTi: (6,75%) masing-masing dengan grup ruang Pnma, P 42/mnm, Pbca dan P 63/mmc.

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The effect of 0.5 weight mol Mn on phase and crystal structure of barium titanate has been analyzed. The best sampel in this study were synthesized using powder metallurgy with stoichiometric amounts of BaCCh, MnO2 and TiO2 that were reagents from E-Merck. The X-ray diffractograms which were obtained with continuous counts and X (Co Ka) = 1.7889 A at room temperature, were refined using the crystallographic software package GSAS. Structural analysis shows that sample consists of 5 (five) phase where the crystal is BaMni,5Ti()5O:, with the perovs kHe-type BaTiO, structure, the space group tetragonal P4mm, a = 3.999 A, t- - 4.025 A. the goodness of fit £ is of 2.175 with 45 variables and the residual parameters Rp and Rwp are of 18.8% and 24.2% respectively. The four phase impurity has a weight fraction is BaCO, (45.83%); MnO, (8.47%); TiO: (20,36%) and Mn:,Ti2 (6,75%) with the space group each are Pnma. P 42/mnm, 1 41/amd and P 63/mmc."

"[ABSTRAKMaterial solder saat ini banyak menggunakan Sn-Pb. Saat ini ada permasalahan lingkungan yaitu Pb yang bersifat racun. Selain itu terjadi fenomena Whiskers yang dapat menyebabkan hubungan pendek pada peralatan elektronikTelah dilakukan sintesa material solder bebastimbal Sn-0.7Cu-xBi/Zn. Pada sampel dilakukan karakterisasi x-ray difraksi. Dilakukan analisis Rietveld untukm emperoleh parameter kristalografidant eksturpa daarah bidang tertentu untuk melihat fenomena whisker.Hasilanilisa Rietveld memperlihatkan penambahan unsurBismut dengan konsentrs i tertentu pada paduan Sn-0.7Cu-xBi dapat merubah teksturpada bidang kristalografi tertentu ditandai dengant ingginya kerapatan pole figure yang dapat diartik antingginya keseragaman orientasikristalit yang dapat menja di penghambat whiskers dibidangtersebut.;

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ABSTRACTSolder material is using Lead (Pb) recently. Toxity of lead was creating environtment issue now. Beside of that whiskers phenomena could make short at electronics circuits.Synthesis of Sn-0.7Cu-xBi/Zn lead free solder materials have been conducted. These alloys were being characterized by using XRD diffractometer. Crystallographic paratemeters and texture of certain plane have been extracted to observe whiskers phenomenaThe result from Rietveld refinement show that adding certain Bismuth concentration could change texture of Sn-0.7Cu-xBi alloy at certain crystall plane. This condition was being show by high density of pole figure, means crystallite orientation more uniform. High density of pole figure at certain crystall plane could become whisker inhibitor.;Solder material is using Lead (Pb) recently. Toxity of lead was creating environtment issue now. Beside of that whiskers phenomena could make short at electronics circuits.Synthesis of Sn-0.7Cu-xBi/Zn lead free solder materials have been conducted. These alloys were being characterized by using XRD diffractometer. Crystallographic paratemeters and texture of certain plane have been extracted to observe whiskers phenomenaThe result from Rietveld refinement show that adding certain Bismuth concentration could change texture of Sn-0.7Cu-xBi alloy at certain crystall plane. This condition was being show by high density of pole figure, means crystallite orientation more uniform. High density of pole figure at certain crystall plane could become whisker inhibitor., Solder material is using Lead (Pb) recently. Toxity of lead was creating environtment issue now. Beside of that whiskers phenomena could make short at electronics circuits.Synthesis of Sn-0.7Cu-xBi/Zn lead free solder materials have been conducted. These alloys were being characterized by using XRD diffractometer. Crystallographic paratemeters and texture of certain plane have been extracted to observe whiskers phenomenaThe result from Rietveld refinement show that adding certain Bismuth concentration could change texture of Sn-0.7Cu-xBi alloy at certain crystall plane. This condition was being show by high density of pole figure, means crystallite orientation more uniform. High density of pole figure at certain crystall plane could become whisker inhibitor.]"

"Providing a comprehensive and invaluable overview of the basics of crystallographic textures and their industrial applications, this book covers a broad range of both structural and functional materials. It introduces the existing methods of representation in an accessible manner and presents a thorough overview of existing knowledge on texture of metallic materials. Texture analysis has widespread use in many industries, and provides crucial input towards the development of new materials and products. There has been rapid growth in the science and art of texture analysis in the last few decades. Other topics addressed within this book include recent research on texture in thin films and non-metals, and the dependence of material properties on texture, and texture control in some engineering materials. This book constitutes an invaluable reference text for researchers and professionals working on texture analysis in metallurgy, materials science and engineering, physics and geology. By using content selectively, it is also highly accessible to undergraduate students."

"Kristal tunggal betaine phosphate disintesis dengan metode solution growth. Kristal berukuran terbesar digerus sehingga menjadi bubuk untuk pengukuran difraksi sinar-X, bercuplikan bubuk. Data difraksi sinar-X dianalisis dengan menggunakan perangkat lunak GSAS untuk mendapatkan informasi mengenai struktur kristal, Struktur kristal digambar dengan ORTEP (bagian dari GSAS). Hasilnya, pada temperatur 30°C dan 120°C, Betaine Phosphate mempunyai sistem kristal monoklinik dan masing-masing memiliki grup ruang P21 /C dan P21 /m dengan CT= 11,051 (1) A, £=7,840(2) A, c= 12,918(6) A, p= 119,590( 12) A, dan o=l 1,099(1) A, £=7,894(1) A, c=6,535(l) A, {3=1 19,783(12) A.

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Single crystalline betaine phosphates have been synthesized by the solution growth method. The biggest size of the crystals were ground for X-ray diffraction measurement of the powder sample. The diffraction data were analyzed using GSAS software resulting refined crystal structural parameters. Crystal structures were drawn with ORTEP. The results were that at temperature 30°C and 120°C betaine phosphate crystallizes in monoclinic P21/C and P2l/m with 0=11.051(1) A, £=7.840(2) A, c=12.918(6) A, (5=119.590(12) A, and o=l 1.099(1) A, £=7.894(1) A, c=6.535(l) A, 0=119.783(12) A, respectively."

"The performance of solar cell with various surface texture patterns was reported. Wet, RIE one and two dimensions texturing with and without the nitridi antireflection coating were compared...."