Synthesis of Polyhedral Magnetite Particles by Hydrothermal Process Under High Pressure Condition

Magnetite particles were successfully generated by hydrothermal synthesis using water at subcritical conditions. By changing the temperature and pressure at subcritical water conditions, the thermodynamics and transport properties of the water can be controlled, thus enabling to manage the way of crystal formation, morphology, and particle size. In this work, the experiments were carried out at temperatures of 250 °C and 290 °C and a pressure of 10 MPa with a reactor made of SUS 316 in a batch system. The synthesized particles were dried in vacuum condition and characterized by SEM and XRD. The XRD patterns showed that magnetite particles were dominantly formed in the particle products with a black color. The results showed that the magnetite particles formed had diameters of around 60 nm in all experiments with irregular polyhedral shaped morphologies

Simulasi Numerik Deposisi Aerosol Partikel Pada Porous Struktur Berbasis Computational Fluid Dynamic (Cfd)

Deposisi partikel didalam porous struktur substrate telah dikembangkan aplikasinya sebagai fotokatalitik, membran filter, dan template untuk material pendukung dalam bidang energi dan lingkungan. Penelitian ini bertujuan untuk mendapatkan kondisi optimum pada deposisi aerosol partikel pada substrat yang mempunyai struktur berpori berdasarkan simulasi numerik dengan software Computational Fluid Dynamics (CFD). Metode simulasi berbasis CFD digunakan sebagai alternatif untuk mereduksi beberapa variabel kondisi yang sulit dikontrol. Permodelan dengan menggunakan CFD ini meliputi tiga tahapan proses, yaitu pre-processing, processing, dan post-processing. Dimensi yang akan digunakan pada CFD ini adalah dengan permodelan 2 dimensi, dimana wall memiliki panjang 10 cm dan lebar 2,5 cm. Analisa yang dilakukan meliputi pola gerakan partikel, kecepatan gerakan partikel, dan jumlah partikel pada porous struktur. Variabel yang ditetapkan pada permodelan ini adalah jarak partikel dengan substrat dan diameter pori dari substrat. Sedangkan ukuran partikel dan kecepatan fluida divariasikan. Hasil penelitian menunjukkan bahwa pola alir dan pergerakan partikel sangat ditentukan oleh kecepatan fluida. Selain itu, semakin kecil partikel yang digunakan maka semakin optimum deposisi yang terjadi, dimana deposisi optimum akan tercapai jika partikel tersebut mempunyai ukuran hingga 36 % dari ukuran pore nya. Deposisi yang optimum juga terjadi jika aliran fluidanya dalam kondisi laminar dan transisi

SIMULASI NUMERIK DEPOSISI AEROSOL PARTIKEL PADA POROUS STRUKTUR BERBASIS COMPUTATIONAL FLUID DYNAMIC (CFD)

Deposisi partikel didalam porous struktur substrate telah dikembangkan aplikasinya sebagai fotokatalitik, membran filter, dan template untuk material pendukung dalam bidang energi dan lingkungan. Penelitian ini bertujuan untuk mendapatkan kondisi optimum pada deposisi aerosol partikel pada substrat yang mempunyai struktur berpori berdasarkan simulasi numerik dengan software Computational Fluid Dynamics (CFD). Metode simulasi berbasis CFD digunakan sebagai alternatif untuk mereduksi beberapa variabel kondisi yang sulit dikontrol. Permodelan dengan menggunakan CFD ini meliputi tiga tahapan proses, yaitu pre-processing, processing, dan post-processing. Dimensi yang akan digunakan pada CFD ini adalah dengan permodelan 2 dimensi, dimana wall memiliki panjang 10 cm dan lebar 2,5 cm. Analisa yang dilakukan meliputi pola gerakan partikel, kecepatan gerakan partikel, dan jumlah partikel pada porous struktur. Variabel yang ditetapkan pada permodelan ini adalah jarak partikel dengan substrat dan diameter pori dari substrat. Sedangkan ukuran partikel dan kecepatan fluida divariasikan. Hasil penelitian menunjukkan bahwa pola alir dan pergerakan partikel sangat ditentukan oleh kecepatan fluida.  Selain itu, semakin kecil partikel yang digunakan maka semakin optimum deposisi yang terjadi, dimana deposisi optimum akan tercapai jika partikel tersebut mempunyai ukuran hingga 36 % dari ukuran pore nya. Deposisi yang optimum juga terjadi jika aliran fluidanya dalam kondisi laminar dan transisi

The effect of ultrasound pretreatment on some selected physicochemical properties of black cumin (Nigella Sativa)

Background In the present study, the effects of ultrasound pretreatment parameters including irradiation time and power on the quantity of the extracted phenolic compounds quantity as well as on some selected physicochemical properties of the extracted oils including oil extraction efficiency, acidity and peroxide values, color, and refractive index of the extracted oil of black cumin seeds with the use of cold press have been studied. Methods For each parameter, three different levels (30, 60, and 90 W) for the ultrasound power and (30, 45, and 60 min) and for the ultrasound irradiation time were studied. Each experiment was performed in three replications. Results The achieved results revealed that, with enhancements in the applied ultrasound power, the oil extraction efficiency, acidity value, total phenolic content, peroxide value, and color parameters increased significantly (P 0.05). Conclusions In summary, it could be mentioned that the application of ultrasound pretreatment in the oil extraction might improve the oil extraction efficiency, the extracted oil’s quality, and the extracted phenolic compounds content.info:eu-repo/semantics/publishedVersio

Centrifugal melt spinning of polyvinylpyrrolidone (PVP)/triacontene copolymer fibres

Polyvinylpyrrolidone/1-triacontene (PVP/TA) copolymer fibre webs produced by centrifugal melt spinning were studied to determine the influence of jet rotation speed on morphology and internal structure as well as their potential utility as adsorbent capture media for disperse dye effluents. Fibres were produced at 72 C with jet head rotation speeds from 7000 to 15,000 r min-1. The fibres were characterised by means of SEM, XRD and DSC. Adsorption behaviour was investigated by means of an isothermal bottle point adsorption study using a commercial disperse dye, Dianix AC-E. Through centrifugal spinning nanofibers and microfibers could be produced with individual fibres as fine as 200–300 nm and mean fibre diameters of ca. 1–2 lm. The PVP/TA fibres were mechanically brittle with characteristic brittle tensile fracture regions observed at the fibre ends. DSC and XRD analyses suggested that this brittleness was linked to the graft chain crystallisation where the PVP/TA was in the form of a radial brush copolymer. In this structure, the triacontene branches interlock and form small lateral crystals around an amorphous backbone. As an adsorbent, the PVP/TA fibres were found to adsorb 35.4 mg g-1 compared to a benchmark figure of 30.0 mg g-1 for a granular-activated carbon adsorbent under the same application conditions. PVP/TA is highly hydrophobic and adsorbs disperse dyes through the strong ‘‘hydrophobic bonding’’ interaction. Such fibrous assemblies may have applications in the targeted adsorption and separation of non-polar species from aqueous or polar environments

Mindfulness, Health And Wellbeing

Well-being isn't simply a lack of illness. It includes various factors affecting an individual's bodily, mental, and social fitness. Pollard and Davidson outline health as “a country of a hit overall performance throughout the existence path integrating bodily, cognitive and social-emotional function”. Practicing mindfulness helps with managing strain and depression. This study considers mindfulness as be a powerful device for dealing with intellectual and bodily fitness issues, in addition to commonly enhancing our overall performance, relationships, and well-being. Keywords: Mindfulness, Health, Wellbein

Abstract of Invited Speaker : Research Opportunities in Japanese Universities and Tips for Scientific Publications

This article gives information for researcher to do research in Japanese Universities based on author\u27s experience and some literatures. Researchers may obtain research opportunities with Japanese Universities through postdoctoral fellowship program provided by Japanese Society for the Promotion of Science (JSPS). Other financial supports to make research collaboration with Japanese Universities may also be applied through JSPS program. In addition, author summarized tips for scientific publications both in International conferences and journals. The tips may help researchers to write a scientific article to be published in an International journa