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"The objective of this research was to reduce coconut sugar melting by enhancing glass transition temperature (Tg). Silicone dioxide (SiO2) and magnesium carbonate (MgCO3) were added before the coconut sugar was formed. Concentrations of SiO2 and MgCO3 were 0.5 %, 1.0 %, and 1.5 % respectively. Analysis was conducted for solidification temperature, moisture content, water activity, and glass transition temperature of coconut sugar. In this research, the glass transition temperature or coconut sugar was measured with differential thermal analyzer (DTA). The result showed that the addition of SiO and MgCO3 was not influenced toward moisture content of coconut sugar, but water activity was decreased. The solidification temperature and glass transition temperature were increased. The best coconut sugar was produced by addition of 1.5 % SiO3 with solidification temperature 72.67 °C, water activity 0.5, and glass transition temperature 70.45 °C "

"Pada proses pengeringan semprot apabila temperatur pengeringan terlalu rendah maka yang terjadi pada bahan cenderung mengalami kelengketan dan partikel serbuk menggumpal. Tomat memiliki moisture content yang rendah tetapi memiliki kadar gula dan likopen yang tinggi sehingga dalam proses pengeringan semprot diperlukan maltodextrin sebagai zat pengikat nutrisi dalam tomat yang berfungsi untuk meningkatkan temperatur gelas transisi (Tg) dan mengurangi kelengketan. Temperatur gelas transisi yang tinggi mampu mengurangi kelengketan. Temperatur transisi gelas (Tg) yang terlalu tinggi akan cepat mengering tetapi partikel bahan akan amorf membentuk kristalisasi dan Tg yang terlalu rendah partikel akan melumer dan lengket. Kondisi droplet untuk temperatur pengeringan jika diatas Tg akan lengket tetapi jika temperatur pengeringan dibawah Tg maka droplet akan kering. Analisa perhitungan temperatur transisi gelas untuk larutan tomat adalah 22,8 °C.

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Spray drying of process if too low drying temperature then occur at substance inclined particle stickiness and agglomerate. Tomato has low moisture content but have to high sugar value and lycopene until process to spray drying needful maltodextrin as nutrition essence on tomato which serves to increase glass transition temperature (Tg). High glass transition temperature (Tg) capable reducing stickiness. Very high glass transition temperature will running dry faster but matter of particle will amorphous crystallization shaping and very low glass transition temperature so particle will be melting and stickiness. Droplet conditions for drying temperature if above of Tg will stick but if the drying temperature is below of Tg so droplet will dry. Analysis calculation glass transition temperature for tomato liquids is 22,8 °C."

"The change of the electric and magnetic properties due to the particle size effect has been reported recently and opened a new door to investigate phenomena driven by dimensional effects. One of the interesting examples is nanogold which is a weak diamagnetic in a bulk state but it becomes ferrimagnetic when the size of the Au cluster is around 3 nm. In the case of the Mott insulating system, it is reported that the magnetic transition temperature, TN, drastically decreased due to nano-sized effects. The reason for the appearance of the ferrimagnetic phase and the reduction in TN are not fully understood and still an open question. We investigated nano-sized effects in typical Mott insulator, La2CuO4, and in high-Tc superconductor cuprates, La2-xSrxCuO4. From muon spin relaxation (μSR) measurements, it is observed that the TN drastically decreased to be 47(12) K with reducing the particle size of La2CuO4 down to 24 nm. The phase separation of long-range and short-range magnetic ordering state was observed. We proposed a core-shell model to describe it. Particle size affects the magnetic interaction in La2CuO4 where the inter-plane magnetic interaction, J’, plays an important role in controlling TN of antiferromagnets. In the case of La1.80Sr0.20CuO4, we found that there is a strong suppression of the superconducting state and the appearance of weak magnetism induced by nano-sized effects. These results revealed that magnetic orders and superconductivity are intertwined and interconnected in high-Tc cuprate superconductors.

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Perubahan sifat listrik dan magnet yang disebabkan efek ukuran partikel telah diteliti secara intensif akhir-akhir ini dan membuka pandangan baru dalam investigasi fenomena yang di-drive oleh efek dimensi. Salah satu contoh efek partikel yang sangat menarik adalah nano-gold. Gold (Au) bersifat dimagnetik lemah dalam keadaan bulk tetapi menjadi ferrimagnetik saat ukuran cluster Au dikecilkan menjadi 3 nm. Di kasus sistem Mott insulating, suhu transisi magnetik, TN, dilaporkan menurun karena nano-sized effects. Alasan munculnya fasa ferrimagnetik dan menurunnya TN di sistem nano masih belum dipahami sepenuhnya dan masih menjadi pertanyaan. Kami menginvestigasi nano-sized effects di typical Mott insulator, La2CuO4, dan high-Tc superconductor cuprates, La2-xSrxCuO4. Dari hasil pengukuran muon spin relaxation (μSR), dihasilkan bahwa TN menurun drastis menjadi 47(12) K dengan dikecilkannya ukuran partikel menjadi 24 nm. Dari hasil μSR, teramati juga adanya pemisahan fasa antara long-range dan short-range magnetic ordering. Core-shell model diajukan untuk menjelaskan pemisahan fasa magnetic ordering yang terjadi di La2CuO4 nanopartikel. Kami menemukan bahwa inter-plane magnetic interaction, J’, berperan penting dalam mengontrol perubahan TN di antiferromagnet. Pada kasus La1.80Sr0.20CuO4, teramati adanya penurunan superconducting state secara drastis dan munculnya weak magnetism yang disebabkan oleh nano-sized effects. Hasil ini menunjukkan bahwa magnetic orders dan superkonduktivitas saling terkait dan berhubungan."

"Kelapa merupakan komodotas penting bagi Indonesia.Selain memenuhi kebutuhan dalam negeri,kelapa juga merupakan komoditas ekspor penghasil devisa. Sebagian besar pertanaman kelapa rakyat belum memenuhi standar budi daya....."

"Biodiesel is an alternative fuel that can be produced from coconut oil through transesterification process using methanol and sodium hydroxide (NaOH) as catalyst. Nowadays , the development of biodiesel is urgently required to reduce people people burden due to the price and the uncertain supply of diesel fuel in small and remote island...."

"Kelapa merupakan salah satu komoditas unggulan kabupaten Tanjung Jabung Timur, Jambi dari. 59.396 ha areal tanaman kelapa yang ada, sebagian terdapat di Kecamatan Muara Sabak. Pertanaman kelapa umumnya terdapat di lahan pasang surut di sepanjang aliran sungai (Dinas Perkebunan Kabupaten Tanjung jabung Timur 2002)...."

"Dengan pertumbuhan penduduk yang tinggi ,sampai saat ini kecukupan kalori dan protein masyarakat Indonesia masih rendah . Untuk itu diperlukan penggalian sumber protein dan karbohidrat alternatif, seperti ubi kayu dan koro-koroan yang tumbuh dengan baik di lahan marginal...."

"Mud of sawit represent processing of coconut of sawit phase of first able to be used as by materials of feeding in livestock having value of gizi high where chemical value of mud of sawit is BK 90,5% PK 11,5%,LK 19,1%,SK 17%,Ca 0,5% and P 0,75% and also gros energy 18 % or 3.353 kkal/kg of energy metabolism (Nitis, 1981)...."

"Latar belakang: Hidroksiapatit merupakan salah satu bahan alloplast yang banyak digunakan di bidang kedokteran gigi. Komposisi hidroksiapatit sama dengan komposisi anorganik tulang dan gigi manusia sehingga bersifat biokompatibel dan bioaktif. Selain itu, hidroksiapatit juga bersifat osteokonduktif. Salah satu metode pembuatan hidroksiapatit yaitu metode disolusi-presipitasi dalam kondisi hidrotermal. Pembuatan blok hidroksiapatit dengan metode disolusi-presipitasi pada suhu 100°C selama 48 jam masih menghasilkan fasa lain selain hidroksiapatit, yaitu dicalcium phosphate anhydrous (DCPA). Fasa DCPA dan/atau fasa DCPD (dicalcium phosphate dehydrate) dapat terbentuk dalam pH asam. Sedangkan, hidroksiapatit dapat terbentuk pada pH basa. Oleh karena itu, pH dapat dijadikan indikator secara tidak langsung mengenai hasil fasa yang terbentuk. Gipsum dipilih sebagai prekursor karena mengandung ion kalsium (Ca2+). Sedangkan, larutan Na3PO4 digunakan karena mengandung ion fosfat (PO43-), bersifat tidak toksik, dan memiliki pH basa. Tujuan: Penelitian ini bertujuan untuk mengetahui pengaruh perbedaan suhu terhadap perubahan pH larutan Na3PO4 dalam pembuatan blok hidroksiapatit dari blok gipsum.Metode Penelitian: Penelitian ini menggunakan blok gipsum dan larutan Na3PO4 sebagai prekursor untuk membuat blok hidroksiapatit. Spesimen yang digunakan berupa 30 mL larutan 1 mol/L Na3PO4 sebanyak dua beaker glass larutan. Sebelum dilakukan perendaman, pH larutan diukur terlebih dahulu untuk mengetahui pH awal larutan 1 mol/L Na3PO4. Lima belas blok gipsum direndam dalam 30 mL larutan 1 mol/L Na3PO4 dengan suhu yang berbeda yaitu 100°C, 140°C, dan 180°C pada kondisi hidrotermal selama 48 jam. Setelah perendaman, blok dan larutan 1 mol/L Na3PO4 dipisahkan. Kemudian, pH larutan 1 mol/L Na3PO4 diukur kembali menggunakan pH meter Eutech Instruments pH 700 untuk mendapatkan pH larutan 1 mol/L Na3PO4 setelah digunakan untuk perendaman selama 48 jam. Hasil: Nilai pH larutan 1 mol/L Na3PO4 sebelum digunakan untuk perendaman yaitu 13,04. Sedangkan, nilai pH larutan 1 mol/L Na3PO4 setelah digunakan untuk perendaman pada suhu 100°C, 140°C, dan 180°C berturut-turut yaitu 12,72; 12,67; dan 12,30. Kesimpulan: Peningkatan suhu yang digunakan menyebabkan penurunan pH larutan 1 mol/L Na3PO4. Namun, pH akhir larutan masih cukup basa untuk hidroksiapatit terbentuk. Namun, penelitian lebih lanjut masih perlu dilakukan mengenai pengukuran pH larutan Na3PO4 dengan sampel yang lebih banyak.

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Background: Hydroxyapatite is one of the alloplastic materials that is widely used in dentistry. The composition of hydroxyapatite is similar with the inorganic composition of human bone so that it is biocompatible and bioactive. Besides, hydroxyapatite is also osteoconductive. One of the fabrication methods of hydroxyapatite is the dissolution-precipitation method under hydrothermal conditions. The fabrication of hydroxyapatite block with the dissolution-precipitation method at 100°C for 48 hours still produced other phase except hydroxyapatite, specifically dicalcium phosphate anhydrous (DCPA). DCPA and/or dicalcium phosphate dehydrate (DCPD) phase can be obtained if the pH is acidic. Meanwhile, hydroxyapatite can be fabricated on the alkaline pH condition. Therefore, the pH value can be the indirect indicator to predict the phase product. Gypsum was chosen as a precursor because it has calcium ions (Ca2+). Na3PO4 solution was used because it contained phosphate ions (PO43+), non-toxic, and has an alkaline pH value.

Objective: This study aimed to determine the effect of temperature differences on changes of the pH value of Na3PO4 solution in the fabrication of hydroxyapatite block from gypsum block.

Methods: This study used gypsum block and Na3PO4 solution as precursors to fabricate hydroxyapatite block. The specimens of this study were two beaker glasses of 30 mL of 1 mol/L Na3PO4 solution. Before the immersion, the pH value of the solution was measured first to determine the initial pH value of 1 mol/L Na3PO4 solution. Fifteen specimens of gypsum blocks were immersed in 30 mL of 1 mol/L Na3PO4 solution with different temperatures specifically 100°C, 140°C, and 180°C under the hydrothermal condition for 48 hours. After the immersion, the blocks and the 1 mol/L Na3PO4 solution were separated. Then, the pH value of 1 mol/L Na3PO4 solution was measured using Eutech Instruments pH 700 pH meter to obtain the pH of 1 mol/L Na3PO4 solution after being used for immersion for 48 hours.

Results: The pH value of 1 mol/L Na3PO4 solution before being used for the immersion was 13,04. Meanwhile, the pH value of 1 mol/L Na3PO4 solution after being used for the immersion at 100°C, 140°C, and 180°C respectively were 12.72, 12.67, and 12.30.

Conclusions: The increase in the temperature caused the derivation of the pH value of 1 mol/L Na3PO4 solution. Nevertheless, the final pH value was still alkaline enough for hydroxyapatite to be formed. However, further research still needs to be done to measure the pH value of the Na3PO4 solution with more samples."