Judul: Aplikasi Karbon Aktif sebagai Penyerap Etilen dan Teknik Pengemasan pada Salak Pondoh (Salacca edulis R.)
Abstrak: Salak pondoh is a highly commercial fruit, but has a short self life, so it decays easily. To ercome this problem, inhibition of its respiration rate can be carried out, i.e. by the adjustment of and CO2 compositions through the packaging, and adsorption of ethylene by giving of ethylene sorbent, such as activated carbon. The objective of this research was to increase the self life of alak by using activated carbon as an ethylene absorbent. This study was carried out by packing salak to polypropylene (PP) and polyethylene (PE) plastic bags with the packaging techniques (holes, rmal, and vacuum), and the addition of activated carbon (3% and 6%), and then were stored it in a Dol chamber at temperature of 15-20 °C and RH of 90-99%. The parameters tested were weight sses, percentage of damage, total suspended solids, and vitamin C. The best treatment obtained Som this study was packaging using PP plastic with vacuum technique and activated carbon dosage 3%. That condition was able to maintain the self life of salak up to 24 days of storage, 14 days Onger. Application of 3% addition of activated carbon was able to maintain the self life for 7 days Tonger at the maturity level of 90% and 11 days longer at the maturity level of 80%, compared to no addition of activated carbon and packed with PP plastic in vacuum condition.
Keyword: Packaging, Salak pondoh, Activated carbon, Eethylene absorbent, Self life

Judul: Kemasan Aktif Buah Salak Pondoh (Salacca edulis Reinw.) dengan Penyerap Gas Etilen dan Gas Karbondioksida
Abstrak: Snake fruit (Salacca edulis Reinw.) is one of the leading agricultural commodities in Indonesia which is currently widely consumed by the public, unfortunately fruits do not have a long shelf life after harvest. This study was purposed to obtain a combination of absorbing ethylene gases and CO2 gases produced from the respiration of fruits in order to extend shelf life. There are two combinations of absorbent material used, the chalk with zeolite and lime with activated charcoal. Zeolites and activated charcoal has a role to absorb the ethylene gas produced during the storage of snake fruit, while the role of lime to absorb CO2 gas produced from the salak respiration during storage. Concentration of each absorber used are: limestone (2.5%), zeolite (2.5%) and activated charcoal (1.5%). Type of plastic used to package the snake fruit is a type of plastic PP and PET with a thickness of 0.8 μm plastic. There are two packaging techniques that applied, with vacuum and normal. Temperature used in the fruits during their storage is 16-20° C with a humidity of 99%. The results of observations, a combination of absorbent materials which can increase the shelf life of salak and produces the smallest percentage of damage is a combination of lime with a zeolite absorbent material in plastic PETnormal. The combination was able to increase the shelf life up to 26 days.
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Judul: Invers Drazin dari Matriks Toeplitz Singular
Abstrak: Matriks Toeplitz adalah matriks yang setiap unsur pada diagonal utama bernilai sama dan setiap unsur pada subdiagonal yang bersesuaian dengan diagonal utama juga bernilai sama. Matriks singular adalah matriks yang tidak bisa ditentukan inversnya. Akan tetapi, dapat diupayakan untuk ditentukan inversnya menggunakan invers matriks yang diperumum. Invers Drazin merupakan salah satu jenis invers matriks yang diperumum. Pada karya ilmiah ini ditentukan invers Drazin dari matriks Toeplitz singular dengan menggunakan metode Leverrier Faddeev. Kemudian, ditentukan invers Drazin dari matriks Toeplitz singular yang direpresentasikan sebagai penjumlahan segitiga bawah dan segitiga atas matriks Toeplitz berdasar pada teorema Gohberg dan Semencul., Toeplitz matrix is a matrix in with element on the main diagonal has the same value and on the subdiagonal corresponding to the main diagonal also has the same value. Singular matrix is a matrix that has no inverse. However, it can be attempted to determine the inverse using a generalized inverse matrix. Inverse Drazin is a type of generalized matrix inverse. This paper discussed the inverse Drazin for a singular Toeplitz matrix using the Leverrier Faddeev method. Then, the Drazin inverse of the singular Toeplitz matrix which is represented as a sum of products of lower and upper triangular Toeplitz matrix based on Gohberg and Semencul theorem.
Keyword: inverse Drazine, singular Toeplitz matrix