Asep Riswoko
Center for Material Technology-Agency for the Assessment and Application of Technology Jl. M.H. Thamrin No. 8, Jakarta 10340, Indonesia

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GRAFTING OF CELLULOSIC PALMITATE-METHYL METHACRYLATE BY ELECTRON BEAM IRRADIATION AND CHARACTERIZATION OF THEIR MEMBRANES MECHANICAL PROPERTIES Riswoko, Asep; Suryanti, Tri
Jurnal Sains Materi Indonesia Vol 12, No 2: FEBRUARI 2011
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (333.576 KB) | DOI: 10.17146/jsmi.2011.12.2.4594

Abstract

GRAFTING OF CELLULOSIC PALMITATE-METHYL METHACRYLATE BY ELECTRON BEAM IRRADIATION AND CHARACTERIZATION OF THEIR MEMBRANES MECHANICAL PROPERTIES. A cellulose derivative membrane, cellulosic palmitate, has been modified to give a better mechanical properties of composite membranes. Modification has been carried out by adding methyl methacrylate (MMA) onto cellulosic palmitate with volume ratio 1:1 and then irradiated by electron beam at dosage of 3, 5, 7, 9, and 10 kGy. The best performance of MMA grafted cellulosic membrane was successfully obtained for irradiation dose at 5 kGy which has a tensile strength of 76,92 Kg/cm2 (stronger than that of the original cellulosic palmitate membrane up to 75%). This result is supported by FT-IR spectra which showed that grafting methyl methacrylate onto cellulosic palmitate increased the intensity of absorbance of -CH2- group (1468.47 and 1450.47 cm-1). In addition, there are also strong absorption in region 1068.64 and 1014.56 cm-1 which is absorption for C-O-C (ether linkage) between cellulosic palmitate and methyl methacrylate. X-Ray Diffraction and SEM analysis were also revealed that adding of MMA on cellulosic palmitate affected a degree of crystalline and morphology membrane.
Optimasi Media Kultivasi Senyawa Aktif Penicillium lagena sebagai Antifungi Patogen Phellinus lamaoensis dengan Menggunakan Respon Surface Methodology Sunaryanto, Rofiq; Nurani, Diana; Riswoko, Asep; Nabilah, Siti; Syamsu, Khaswar
Seminar Nasional Lahan Suboptimal 2018: Prosiding Seminar Nasional Lahan Suboptimal "Tantangan dan Solusi Pengembangan PAJALE dan Kel
Publisher : Seminar Nasional Lahan Suboptimal

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (589.616 KB)

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Sunaryanto et al, 2019. Optimization of Penicillium lagena Medium Cultivation on Antifungal Pathogen of Phellinus lamaoensis using Response Surface Methodology. pp. 410-420. Phellinus lamaoensis (Murr.) Hein is fungal pathogen that can cause brown root rot disease in cocoa, tea, rubber, and coffee plants. Endophytic fungi, Penicillium lagena, isolated from bandotan (Ageratum conyzoides Linn.), medicinal plant, is able to inhibit the growth of pathogenic, P. lamaoensis. The effect of carbon source, nitrogen source, and mineral solution was studied. Lactose, yeast extract, and mineral solution were media components which showed significant effect toward production of P. lagena active compound. Composition optimization of these three medium components was done by response surface methodology (RSM). The Optimal response region of the significant factor was predicted by using a second order polynomial model with statistical design, central composite design (CCD). Higest production of P. lagena active compound by quadratic model was predicted to be 69.233% with medium composition 44.77 g L-1 lactose, 13.02 g L-1 yeast extract, and 15.95 mL L-1 mineral solution. Verification value in laboratory is 58.365%, lower 15.7% than its prediction. Optimization increase P. lagena active compound 9 fold compared to unoptimize media.
SINTESIS DAN KARAKTERISASI STRUKTUR KRISTALCAIR FEROELEKTRIKTIPE ESTER BENZOAT TURUNAN DARIASAM (S)-(+)-2-METILBUTANOAT Riswoko, Asep; Afrizal, Afrizal; Setioko, Wahyu
Jurnal Sains Materi Indonesia Vol 12, No 3: JUNI 2011
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1055.548 KB) | DOI: 10.17146/jsmi.2011.12.3.4611

Abstract

SINTESIS DAN KARAKTERISASI STRUKTUR KRISTALCAIR FEROELEKTRIKTIPE ESTER BENZOAT TURUNAN DARIASAM (S)-(+)-2-METILBUTANOAT. Metode sintesis kristal cair feroelektrik tipe ester benzoat turunan dari asam (S)-(+)-2-metil butanoat telah berhasil dikembangkan melalui metode esterifikasi (S)-(+)-p-hidroksifenil-2-metilbutanoat ((S)-(+)-2-HFM) dengan akriloksi butiloksi benzoat (ABB). Senyawa kiral alkohol (S)-(+)-2-HFM diperoleh dengan esterifikasi Steglich menggunakan hidrokuinon dengan katalis disikloheksil karbodiimida (DCC) dan dimetil amino piridin (DMAP). Sedangkan akrilat ABB diperoleh dari hasil sintesis senyawa induk asam 4-klorobutil asetat melalui pembentukan eter Williamson yang diikuti hidrolisis basa dan dilanjutkan dengan akrilasi. Karakterisasi struktur kristal cair feroelektrik yang berasal dari kedua prekursor ini dengan Fourier Transform - Infra Red (FT-IR) menunjukkan ester dengan gugus karbonil dan fenil tanpa gugus hidroksi. Puncak serapan spektrum FT-IR produk ester (cm-1): 3323,53; 2851,03; 2666,01; 1729,09; 1622,86; 1536,74; 1510,75; 1244,16; dan 1170,16.