Judul: Manufacture and Characterization of Physical Properties of Non-Wood Paper from Palm Oil Solid Waste as Packaging Paper
Abstrak: Penelitian ini bertujuan membuat kertas dari bahan non-kayu, yaitu limbah padat kelapa sawit, yang bernilai ekonomis serta menganalisis sifat fisiknya. Proses yang digunakan untuk membuat pulp serat mesokarp dan tandan kosong kelapa sawit (TKKS) adalah metode kimia menggunakan NaOH 10% selama 60 menit, pada suhu 100 ℃. Kertas dibuat dengan nisbah pulp limbah kelapa sawit dan kertas bekas 60:40 dan 70:30 dengan tambahan perekat 2−5%. Kertas dengan kualitas terbaik dihasilkan dari nisbah serat mesokarp dan TKKS 60% dan kertas bekas 40% dengan tambahan perekat 5%. Kertas dari campuran serat mesokarp dan kertas bekas menghasilkan gramatur sebesar 157,0 g/m2, kekuatan tarik 0,94 kN/m, dan ketahanan sobek 511,8 mN. Kertas dari TKKS menghasilkan nilai gramatur sebesar 134,7 g/m2, kekuatan tarik 0,87 kN/m, dan ketahanan sobek 441,1 mN. Hasil penelitian menunjukkan bahwa gramatur dan ketahanan sobek kertas dari serat mesokarp dan TKKS sudah sesuai SNI 8218:2015, sedangkan kekuatan tarik belum memenuhi standar. Spektrum inframerah menunjukkan bahwa kedua kertas mengandung selulosa dan lignin., This research aimed to prepare low-cost non-wood paper and analyze the properties of non-wood paper produced from palm oil solid waste. The method used to make mesocarp fiber pulp and empty fruit bunch (EFB) pulp was a chemical method using 10% NaOH for 60 minutes at a temperature of 100 ℃. The paper was prepared with a 60:40 and 70:30 ratios of palm oil waste pulp and waste paper with the addition of 2-5% adhesive. The best-quality paper was produced from 60% palm oil waste pulp and 40% waste paper with 5% adhesive added. Mesocarp fiber paper has grammage of 157.0 g/m2, a tensile strength of 0.94 kN/m, and a tear resistance of 511.8 mN. The EFB paper has a grammage of 134.7 g/m2, a tensile strength of 0.87 kN/m, and a tear resistance of 441.1 mN. As result, the grammage and tear resistance of paper from mesocarp fibers and EFB met the requirements of SNI 8218:2015, while the tensile strength did not meet the standard. The infrared spectrum showed that both papers contained cellulose and lignin.
Keyword: EFB, mesocarp fiber, packaging paper, palm oil waste

Judul: Penggunaan Selulosa TandanKosong Kelapa Sawit dan Selulosa Mikrobial dari Nata de Cassavasebagai Pensubstitusi Selulosa Kayu dalam Pembuatan Kertas
Abstrak: Nowadays, forest-extracted wood cellulose still predominantly serves as raw material for pulp and paper manufacture in Indonesia. Consequently, the deforestation rate has alarmingly increased 2% per year. Attempts are necessary to seek alternative cellulose sources that sound potentially available, among which are empty oil-palm fruit bunches (EOPFB) and microbial-cellulose, as synthesizedwith the aid of microorganisms from substrate containing glucose, fructose, sucrose, or other simple carbohydrates, such as juicy waste from tapioca processing (e.g. nata de cassava). In this research, pulp of nata de cassava‟s microbial cellulose was mixed with EOPFB pulp at various proportions (w/w), i.e. 100%+0%, 75%+25%, 50%+50%, 25%+75%, 0%+100%to be processed into pulp and paper. Grammage target made was 60 gr/m2 and 120 gr/m2. Prior to paper-sheet forming, additives were added to such mixture (i.e. 2% alum, 2.5% tapioca starch, and 5% kaolin). Sheet forming also made without additives (as control). The forming of each combination between mixture proportion, grammage target and additive/control-use was replicated 2 times, and the data examined comprised pulp/paper physical and strength properties. The data were analyzed using a completely randomized design with factorial pattern. The yields of microbial-cellulose pulp and of EOPFB pulp were consecutively (wet basis) 60,09% and 61,619%. Physical and strength properties of paper with grammage 60 gr/m2and 120gr/m2consecutively, i.e. water content (4,04-8,95% & 3,83- 9,01%), grammage (59,8-78,92gr/m2& 107,64-145,32 gr/m2), tensile index 0,0056-0,0424 & 0,01002-0.06499 kNm/g), tear index (4,04-8,22 & 4,55-7,72 mN m2/gr),folding endurance (3,5-108,5 & 4-397,5), Cobb60 (56,86-211,32 & 75,03- 398,12 g/m2 for the smooth surface; and 51,07-218,91 & 57,65-404,46 g/m2for the rough/lower surface), brightness (15,64-38,03% & 13,1-26,26%) and printing opacity (62,81-97,55% & 42,99-99,38%). Analysis on biomass conversion revealed that the manufacture of paper from the mixture (w/w) of nata de cassava‟s microbial cellulose (50%) and empty oil palm fruit bunch pulp (50%) through the expansion of each cultivating areas, both totaling 200 ha can substitute for 4.247.156forest-tree stands per year. With this tree-saving figure, it can afford the CO2absorption (uptake) from the air equal to approximately 594.601,85 tons of CO2 per year.
Keyword: carbon uptake, biomass conversion analysis, pulp/paper, empty oil-palm fruit bunch, nata de cassava, microbial cellulose

Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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