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"The growth and crystallization processes of the Cu2ZnSnS4 (CZTS) phase typically rely on high-temperature sulfurization, which involves a harmful chalcogen-containing atmosphere. Together with the use of high-toxicity solvents, these processes could hinder the widespread adoption of this technology in the mass production of CZTS semiconductors for solar cell application. Thus, we studied the formation of CZTS films from ethanol-based precursors without the sulfurization step, fully employing the non-toxic solvent and avoiding the environmentally harmful sulfur-containing atmosphere. The certain addition of 2-mercaptopropionic acid led to the formation of a clear and stable sulfur-containing precursor. The precursors were successfully deposited onto soda lime glass by employing spin coater. CZTS crystallinity in the identified XRD patterns was vanishingly small in the case of eliminating the sulfurization process. Moreover, the carbon concentration and grain size of the resulting films were controlled by changing the time period of drying treatment during film fabrication. A drying time of 120 minutes, which demonstrated a CZTS grain size of ± 1 µm with a direct optical energy gap around 1.4 eV, was confirmed as the ideal condition. These results may provide a useful route toward environment-friendly strategies for the production of a CZTS semiconductor that is compatible with the absorber application in thin-film solar cells."

"The growth and crystallization processes of the Cu2ZnSnS4 (CZTS) phase typically rely on high-temperature sulfurization, which involves a harmful chalcogen-containing atmosphere. Together with the use of high-toxicity solvents, these processes could hinder the widespread adoption of this technology in the mass production of CZTS semiconductors for solar cell application. Thus, we studied the formation of CZTS films from ethanol-based precursors without the sulfurization step, fully employing the non-toxic solvent and avoiding the environmentally harmful sulfur-containing atmosphere. The certain addition of 2-mercaptopropionic acid led to the formation of a clear and stable sulfur-containing precursor. The precursors were successfully deposited onto soda lime glass by employing spin coater. CZTS crystallinity in the identified XRD patterns was vanishingly small in the case of eliminating the sulfurization process. Moreover, the carbon concentration and grain size of the resulting films were controlled by changing the time period of drying treatment during film fabrication. A drying time of 120 minutes, which demonstrated a CZTS grain size of ± 1 µm with a direct optical energy gap around 1.4 eV, was confirmed as the ideal condition. These results may provide a useful route toward environment-friendly strategies for the production of a CZTS semiconductor that is compatible with the absorber application in thin-film solar cells."

"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).

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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)."

"Interaksi RKKY (Ruderman-Kittel-Kasuya-Yosida) adalah interaksi exchange tidak langsung antara dua buah momen magnet terlokalisasi yang dimediasi oleh elektron pita konduksi. Interaksi exchange tidak langsung dalam struktur multilayer magnetik spin valve bisa dimediasikan oleh elektron konduksi milik lapisan pemisah non-magnetik. Interaksi RKKY umum ditemukan pada struktur multilayer yang lapisan pemisahnya bersifat konduktor listrik. Namun dalam eksperimen ditemukan lapisan pemisah LaAlO3 dalam struktur spin valve bisa memediasikan interaksi exchange berjarak jauh meskipun memiliki sifat sebagai insulator. Dalam penelitian ini, kami meneliti mekanisme interaksi RKKY di dalam LaAlO3. Dalam eksperimen lain, ditemukan bahwa transfer muatan bisa menginduksi munculnya sifat konduktor pada LaAlO3. Untuk mempelajari efek transfer muatan, pendekatan density functional theory (DFT) dilakukan di dalam penelitian ini untuk mendapatkan struktur pita elektronik LaAlO3 dengan doping muatan. LaAlO3 yang tidak terdoping memiliki celah pita sebesar 3 eV dengan puncak pita valensi dan lembah pita konduksi masing-masing berada di titik R dan Γ. Kami menunjukkan sifat konduktor muncul dari energi Fermi yang meningkat melalui doping muatan. Dengan tambahan doping muatan pada perhitungan DFT, kami menunjukkan bahwa LaAlO3 bisa memiliki sifat konduktor yang sesuai dengan eksperimen transfer muatan pada LaAlO3. Selanjutnya, LaAlO3 bersifat konduktor bisa memediasi interaksi RKKY dalam struktur spin valve. Penelitian ini bermanfaat untuk aplikasi LaAlO3 dan semikonduktor dalam heterostruktur magnetik.

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RKKY interaction is an indirect interaction between localized magnetic moments mediated by conduction electron. Indirect exchange interactions between two magnetic layers in spin valve structure can be mediated by the conduction electron of the nonmagnetic spacer. RKKY exchange interaction is mostly found in magnetic multilayer involving conductor as the non-magnetic spacer. However, recent experiment shows that LaAlO3 spacer can intermediate of long-range exchange interaction even though it is an insulator. Here we study the mechanism of RKKY interaction in LaAlO3. An experiment shows that charge transfer can induce a conducting characteristic of LaAlO3. To study the effect of charge transfer, we perform a density functional theory (DFT) approach to obtain the band structure of LaAlO3 with charge doping. Undoped LaAlO3 has an indirect band gap around 3 eV with peak valence at R symmetry point and lowest conduction point at Γ point. We show that the conducting characteristic arise from Fermi energy shifts via charge doping. By adding charge doping into DFT calculation, we show that LaAlO3 can have conductor characteristic, in agreement with charge transfer experiment on LaAlO3. Furthermore, the conducting LaAlO3 is able to mediate RKKY interaction in spin valve structure. Our study is useful for application of LaAlO3 and semiconductor by extension in magnetic heterostructures."

"Polylactid acid (PLA) adalah plastik berbasis alam yang memiliki potensial yang besar untuk menggantikan plastik berbasis minyak bumi karena tingginya modulus young dan kuat tariknya. Akan tetapi PLA memiliki kekurangan yaitu ketangguhan dan kecepatan kristalisasinya yang rendah yang membatasi aplikasinya.Pada penelitian ini, PLA diperkuat oleh serat bambu dengan perlakuan berbeda seperti perlakuan alkali (NaOH) dan perlakuan pemutihan (NaClO) yang bertujuan untuk meningkatkan kristalinitas PLA. Kandungan serat bambu dalam komposit adalah 5, 10 dan 20 %. Kandungan kimia dan kristalintas serat diselidiki dengan menggunakan FTIR (Fourier Transform Infra Red ) dan XRD (X ray Diffraction). Terbukti bahwa terjadi peningkatan kristalinitas seiring dengan penurunan lignin dan hemiselulosa. Kristalinitas serat bambu yang tidak diberi perlakuan adalah 56,5 %, sedangkan dengan perlakuan alkali adalah 64 % dan dengan perlakuan pemutihan adalah 66,6 %. Untuk mengetahui efek kristalinitas terhadap PLA dilakukan uji DSC (differensial Scanning Calorimetri) dan XRD pada masing – masing sampel komposit. Hasil XRD menunjukkan adanya interaksi antara serat dan PLA serta menunjukkan adanya peningkatan kristalinitas. Peningkatan kristalinitas terjadi ketika penambahan kandungan 10 % dan 20 % serat tetapi tidak pada kandungan serat 5 %. Tanpa memperhatikan komposit PLA – serat bambu kandungan serat 5 %, kristalinitas tertinggi terjadi pada PLA – serat bambu hasil perlakuan pemutihan. Sedangkan hasil DSC menujukkan kecenderungan peningkatan kristalinitas seiring dengan bertambahnya kandungan serat.

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Polylactid acid (PLA) is a bio-based palstic that has a great potential to replace petroleum-based plastic due to its high Young's modulus and tensile strength. However, the drawbacks of PLA are low toughness and slow crystallization speed limited it's application. In this study, PLA reinforced by bamboo fibers with different treatments such as alkali treated (NaOH) and bleaching treated (NaClO) in order to improve the crystallinity of PLA. The concentration of bamboo fiber in the composite were 5, 10 and 20 wt%. The chemical content and cystallinity of fiber was investigated by FTIR (Fourier Transform Infra Red ) and XRD (X ray Diffraction). It was proved that the crystallinty of fiber was increased with decreasing of lignin and hemicellulose. Bamboo fibers without treatment has 56,5 % cystallinity, while alkali treatment 64 % crystallinity and fiber bleaching treatment has 66,6 % crystalllinity. To determine the crystallinity effect of treated fiber on PLA composite, DSC (Differential Scanning Calorimetry) and XRD test was conducted on each composite sample. XRD result showed the interaction between fibers and PLA and an increasing of crystallinity with increasing of fiber content. The increasing of crystallinity happened on 10 % and 20 % fiber content but not in composite with 5 % fiber content. By obeying 5 % fiber content on PLA, the best cystallinty was PLA - bleached bamboo fiber composite. The DSC data showed that increasing of fiber content resulted in increasing crystallization rate of PLA."

"Pembukaan konstitusi proklamasi, undang-undang dasar negara republik Indonesia tahun 1945 ( UUD NRI 1945) merupakan kristalisasi dari cita negara dan cita hukum negara republik Indonesia . Dalam pembukaan konstitusi tersebut terkandung alasan, tujuan dan misi negara berlandaskan nilai dasar pancasila.embukaan dianggap bertentangan dengan semangat pembukaan dianggap bertentangan dengan konstitusi."

"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."

"Tujuan. Menganalisis efek aplikasi NSF dan PPF terhadap remineralisasi dentin melalui uji kristalinitas.Metode. Dentin blok dibagi dalam sembilan kelompok, yaitu kelompok kontrol positif dan negatif dan tujuh kelompok perlakuan. Kontrol negatif merupakan dentin normal dan kontrol positif merupakan dentin yang didemineralisasi. Kelompok perlakuan diaplikasikan NSF dan PPF dengan konsentrasi yang berbeda. Karakteristik kristal dari seluruh dentin blok diuji oleh X-Ray Diffraction XRD.Hasil. Gambaran XRD memperlihatkan senyawa apatit, senyawa kalsium, dan senyawa logam dalam kelompok perlakuan lebih tinggi dibandingkan kelompok kontrol positif.Kesimpulan. NSF dan PPF efektif terhadap remineralisasi dentin.

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To analyze the effects of NSF and PPF application to dentin remineralization by crystallinity test.

Method. Dentin blocks were allocated to nine groups, control groups positive and negative and seven treatment groups. Control negative is sound dentin and control positive is demineralized dentin. The treatment groups were applied of NSF and PPF with different concentration. The crystal characteristics of dentin blocks were investigated by X Ray Diffraction XRD.

Result. XRD revealed precipitates of apatite compounds, calcium compounds, and metal compounds in treatment groups higher than in control positive group.

Conclusion. NSF and PPF were effective for dentin remineralization. "