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Abstrak :
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. ......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.

Abstrak :
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

Abstrak :
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. ......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.