Hasil Pencarian  ::  Simpan CSV :: Kembali

Abstrak :
[ABSTRAK Pada aplikasinya, konstruksi jalan masih memiliki banyak kelemahan antara lain mudah rusak pada saat terdapat genangan air sehingga akan memperpendek umur pakai jalan. Pada penelitian ini akan dilakukan modifikasi dari bitumen yang merupakan bahan utama pembuatan jalan dengan cara penambahan High Density Polyehtylene (HDPE) dan liginin pada campuran bitumen pen 60/70. Hal ini dapat menurunkan nilai penetrasi sehingga menjadikan bitumen lebih keras dan tahan ketika diberikan beban kendaraan yang berulang, meningkatkan titik lembek, dan menurunkan daktilitas. Selain itu, penambahan lignin sebagai coupling agent dapat meningkatkan kompaktibilitas antara HDPE dengan bitumen karena lignin yang memiliki gugus polar dan non-polar. Kadar lignin yang digunakan yaitu 0,1%, 0,3%, dan 0,5%. Selain itu, penelitian ini juga ingin mengetahui pengaruh temperatur proses yaitu 140˚C, 160˚C dan 180˚C dan waktu pencampuran yaitu 15, 30, dan 45 menit terhadap sifat bitumen hasil modifikasi. Untuk itu dilakukan pengujian mekanik dan karakterisasi campuran untuk melihat kekuatan dari bitumen dan kompatibilitas antara bitumen, HDPE, dan lignin. Pengujian dilakukan melalui uji daktilitas, penetrasi, dan titik lembek. Sedangkan, karakterisasi dilakukan dengan menggunakan Fourier Transform Infrared (FTIR), Thermo Gravimetric Analyzer (TGA), dan Differential Scaning Calorimetry (DSC). Dari hasil pengujian menunjukkan semakin tinggi kadar dari liginin dan semakin tinggi temperatur proses yang digunakan maka semakin tinggi juga kekuatan bitumen modifikasi dalam menahan beban serta semakin tinggi ketahanan termalnya. Kompatibilitas yang baik didapat pada penambahan lignin 0,5% dan temperatur proses 180&#deg;C.

---

ABSTRACT In the application, road construction still has some weakness such as easily damaged, especially when wet patch of water exists. In this case, it will shorten the lifespan of the road. In this study, therefore, the main purpose is to modify the bitumen, which is the main ingredient of asphalt for road construction. The work was performed by adding high density polyethylene (HDPE) and lignin into the bitumen mix pen 60/70. It was expected that it could decrease the penetration?s value so it will make the asphalt harder and resistant to the load, increase the softening point, and thus lower the ductility. The addition of lignin was expected to function as a coupling agent and could increase the compatibility between HDPE and bitumen. This can be understood since lignin has a polar and a non-polar groups. Concentration of lignin used was 0.1, 0.3, and 0.5 wt.% at processing temperature of 140oC, 160oC and 180oC and mixing times of 15, 30, and 45 minutes. Characterization was performed by using a Fourier Transform Infrared (FTIR), Thermogravimetric Analyzer (TGA), and Differential Scanning Calorimetry (DSC), whereas the mechanical testing of the modified bitumen was performed through ductility testing, penetration, and softening point. The results showed that high level of lignin and high temperature of the process resulted in high strength of the modified bitumen and so does the thermal resistance. The best result was obtained in the addition of 0.5 wt.% lignin at a process temperature of 180°C.;In the application, road construction still has some weakness such as easily damaged, especially when wet patch of water exists. In this case, it will shorten the lifespan of the road. In this study, therefore, the main purpose is to modify the bitumen, which is the main ingredient of asphalt for road construction. The work was performed by adding high density polyethylene (HDPE) and lignin into the bitumen mix pen 60/70. It was expected that it could decrease the penetration?s value so it will make the asphalt harder and resistant to the load, increase the softening point, and thus lower the ductility. The addition of lignin was expected to function as a coupling agent and could increase the compatibility between HDPE and bitumen. This can be understood since lignin has a polar and a non-polar groups. Concentration of lignin used was 0.1, 0.3, and 0.5 wt.% at processing temperature of 140oC, 160oC and 180oC and mixing times of 15, 30, and 45 minutes. Characterization was performed by using a Fourier Transform Infrared (FTIR), Thermogravimetric Analyzer (TGA), and Differential Scanning Calorimetry (DSC), whereas the mechanical testing of the modified bitumen was performed through ductility testing, penetration, and softening point. The results showed that high level of lignin and high temperature of the process resulted in high strength of the modified bitumen and so does the thermal resistance. The best result was obtained in the addition of 0.5 wt.% lignin at a process temperature of 180oC., In the application, road construction still has some weakness such as easily damaged, especially when wet patch of water exists. In this case, it will shorten the lifespan of the road. In this study, therefore, the main purpose is to modify the bitumen, which is the main ingredient of asphalt for road construction. The work was performed by adding high density polyethylene (HDPE) and lignin into the bitumen mix pen 60/70. It was expected that it could decrease the penetration’s value so it will make the asphalt harder and resistant to the load, increase the softening point, and thus lower the ductility. The addition of lignin was expected to function as a coupling agent and could increase the compatibility between HDPE and bitumen. This can be understood since lignin has a polar and a non-polar groups. Concentration of lignin used was 0.1, 0.3, and 0.5 wt.% at processing temperature of 140oC, 160oC and 180oC and mixing times of 15, 30, and 45 minutes. Characterization was performed by using a Fourier Transform Infrared (FTIR), Thermogravimetric Analyzer (TGA), and Differential Scanning Calorimetry (DSC), whereas the mechanical testing of the modified bitumen was performed through ductility testing, penetration, and softening point. The results showed that high level of lignin and high temperature of the process resulted in high strength of the modified bitumen and so does the thermal resistance. The best result was obtained in the addition of 0.5 wt.% lignin at a process temperature of 180oC.]

Abstrak :
Saat ini sudah banyak sekali produk-produk berbasis material polimer khususnya plastik. Namun, plastik sangat tidak ramah lingkungan karena sifatnya yang sulit untuk terdegradasi. Biokomposit yang mengandung matriks polimer dan serat alam merupakan salah satu alternatif dalam mereduksi penggunaan produk-produk plastik karena sifatnya yang mudah terdegradasi oleh alam. Serat alam yang memiliki potensi bagus untuk dijadikan sebagai penguat ialah serat sorgum. Selulosa dari serat sorgum diperlukan untuk menghasilkan penguat yang baik pada matriks polimer. Selulosa ini bisa didapatkan dengan mendefibrilasi serat sorgum sehingga kandungan non-selulosa seperti lignin dan hemiselulosa dapat berkurang. Proses defibrilasi dilakukan menggunakan teknik hidrotermal dengan metode rendam bertekanan dengan variasi waktu proses selama 5, 10, 15, 20, 25, 30, dan 60 menit. Hasil menunjukkan bahwa nilai optimum dalam mendefibrilasi serat sorgum terdapat pada proses hidrotermal rendam bertekanan selama 5 menit. Serat sorgum yang dihasilkan memiliki permukaan yang halus dan mengalami peningkatan kristalinitas, hidrofilisitas, dan kestabilan termal.

---

Nowadays, we have a lot of polymer based products, especially plastic. However, the plastic is not very environmentally friendly because it is difficult to degrade. Biocomposites containing polymer matrix and natural fibers is an alternative in reducing the use of plastic products because of its ease biodegradable. Natural fiber that has good potential to be used as a reinforce is sorghum fiber. Cellulose from sorghum fiber is required to produce a good compatibility with polymer matrix. This cellulose can be obtained by defibrillate the sorghum fibers so that non cellulose content such as lignin and hemicellulose can be reduced. The defibrillation process was performed using hydrothermal technique with pressure soak method with variation of processing time for 5, 10, 15, 20, 25, 30, and 60 minutes. The results showed that the optimum value in the defibrillation of sorghum fiber was found in the hydrothermal pressurized soak process for 5 minutes. The resulting sorghum fiber has a smooth surface and increases in crystallinity, hydrophilicity, and thermal stability.

Abstrak :
ABSTRAK
Faktor keamanan dan kinerja merupakan aspek fundamental pada peralatan medis. Untuk menjamin kualitas dan keamanan pada peralatan Elektroensefalograf (EEG), salah satunya ialah harus memenuhi syarat kompatibilitas terhadap elektromagnetik (EMC) yang secara khusus diatur pada standar IEC 60601-1- 2:2014. Pada penelitian ini, telah dilakukan analisis dan pengembangan aspek kompatibilitas elektromagnetik terhadap prototipe EEG berbasis Arduino Uno mengacu standar IEC 60601-1-2:2014. Hasil dari penelitian ini menunjukkan emisi radiasi elektromagnetik pada prototipe EEG dapat diturunkan dengan modifikasi PCB, menambah ferrite bead pada kabel USB dan menambah shield. Dengan menggabungkan ketiga metode tersebut, level emisi radiasi pada rentang frekuensi 30MHz sampai 1GHz dapat diturunkan, sehingga berada di bawah limit standar. Penurunan terbesar level emisi radiasi elektromagnetik terjadi pada frekuensi 35.9MHz yaitu sebesar 27.7 dB. Pengembangan dengan menggabungkan ketiga metode tersebut tidak berdampak pada level emisi melalui konduksi, sehingga masih tetap berada dibawah limit standar. Prototipe EEG yang telah diberi penambahan varistor dan ESD (Electrostatic Discharge) suppressor juga terbukti mampu bertahan dari kerusakan permanen saat pengujian imunitas dengan level surge sampai 1kV dan pengujian ESD secara kontak sampai 8kV.

---

ABSTRACT
Safety and performance of medical devices are fundamental aspects to be concerned. To ensure the quality and safety of electroencephalograph ( EEG ), one of the requirement is electromagnetic compatibility (EMC) which is specifically regulated by IEC 60601-1-2: 2014 standard. EMC aspect of Arduino Uno based EEG prototype was analyzed and developed refer to IEC 60601-1- 2:2014. The results of this study indicated emission of electromagnetic radiation on EEG prototype can be derived by PCB modification, added ferrite beads on the USB cable and added a shield. By combining these three methods, radiated emission level at frequency range 30MHz until 1GHz was reduced until below the standard limit. The largest reduction of electromagnetic radiated emission level occured at frequency 35.9MHz with value 27.7 dB. Combination of these three methods on a EEG prototype did not impact on the level of emissions through conduction, and it remained below the standard limit. EEG prototype that has been fitted with varistor and ESD (Electrostatic Discharge ) suppressor also proved to be able to withstand from permanent damage at the level surge immunity testing up to 1kV , and contact ESD testing up to 8kV.

Abstrak :
Pirfenidon yang diberikan secara oral dalam terapi idiopathic pulmonary fibrosis (IPF) dapat mengakibatkan munculnya efek samping sistemik yang berpotensi menurunkan efektivitas terapi. Penelitian ini bertujuan untuk mengembangkan mikropartikel pirfenidon untuk penghantaran pulmonal yang dapat mengurangi paparan sistemik dan efek samping sistemik dari pirfenidon. Sepuluh formula mikropartikel pirfenidon dibuat dengan memvariasikan konsentrasi polimer (sodium karboksimetil selulosa dan sodium alginat) dan konsentrasi porogen (amonium bikarbonat). Mikropartikel pirfenidon dibuat dengan metode semprot kering. Karakterisasi fisikokimia, studi stabilita, dan uji kompatibilitas in vitro dilakukan untuk mengevaluasi mikropartikel pirfenidon. Hasil penelitian menunjukkan bahwa formula dengan sodium alginat 1,0% dan amonium bikarbonat 0,3% (F10) memiliki potensi yang paling baik untuk penghantaran pulmonal. F10 memiliki mass median aerodynamic diameters (MMADs) 0,065; 0,597; 2,212; dan 5,626 µm yang ideal untuk deposisi di daerah bronkiolar hingga alveolar. Studi stabilita menunjukkan bahwa kadar pirfenidon dalam mikropartikel stabil selama 24 minggu pada penyimpanan suhu 30o ± 2oC dan 40o ± 2oC dengan rentang 99,08-100,00% dan 98,83-100,00%. Nilai MMAD mikropartikel pirfenidon menunjukkan peningkatan selama studi stabilita hingga 5,895 µm dan 6,273 µm pada suhu 30o ± 2oC dan 40o ± 2oC karena adanya agregasi. Hasil studi viabilitas in vitro menunjukkan bahwa pirfenidon dan F10 secara berturut-turut memiliki nilai IC50 sebesar 685,76 µg/ mL dan 437,58 µg/ mL. Studi pelepasan IL-6 dari sel A549 pada konsentrasi di bawah IC50 dan konsentrasi IC50 menunjukkan pelepasan IL-6 yang lebih rendah ketika diinkubasi dengan F10 (5367 ± 346 pg/mL pada 300 µg/mL dan 8707 ± 538 pg/ mL pada 440 µg/ mL) dibandingkan pirfenidon (8900 ± 327 pg/mL pada 300 µg/mL dan 11299 ± 161 pg/ mL pada 690 µg/ mL). Berdasarkan data – data di atas, F10 menunjukkan karakteristik yang sesuai untuk penghantaran pulmonal pirfenidon dalam terapi fibrosis paru. ......Orally administered pirfenidone in idiopathic pulmonary fibrosis (IPF) induced numerous systemic adverse effects that decreased the effectiveness of therapy. This study aimed to develop pirfenidone microparticles for pulmonary delivery to reduce systemic exposure and, subsequently, its systemic adverse effects. Ten formulas of pirfenidone microparticles were prepared using the spray-drying method by varying the concentration of polymers (sodium carboxymethyl cellulose and sodium alginate) and porogen (ammonium bicarbonate). The physicochemical characterization, stability study, and in vitro compatibility study were conducted to evaluate these microparticles. The results showed that F10, which consisted of sodium alginate 1.0% and ammonium bicarbonate 0.3%, had the most promising results. F10 had mass median aerodynamic diameters (MMADs) of 0.065, 0.597, 2.212, and 5.626 µm, which were ideal for deposition in the bronchiolar to the alveolar region. The stability study showed that the pirfenidone content was stable for 24 weeks at 30o ± 2oC and 40o ± 2oC with a range of 99.08-100.00% and 98.83-100.00%. The MMAD was increased up to 5.895 µm and 6.273 µm at 30o ± 2oC and 40o ± 2oC, respectively, due to aggregation. In vitro viability study showed that F10 at 62.5 µg/ mL had the highest cell viability with IC50 of 437.58 µg/ mL. The IL-6 released study showed that the A549 cell released lower IL-6 concentration when incubated with F10 (5367 ± 346 pg/mL at 300 µg/mL and 8707 ± 538 pg/ mL at 440 µg/ mL) than pirfenidone (8900 ± 327 pg/mL at 300 µg/mL and 11299 ± 161 pg/ mL at 690 µg/ mL). In conclusion, F10 shows suitable characteristics for pulmonary pirfenidone delivery in pulmonary fibrosis therapy.