Judul: Efektivitas Emulsifiable Concentrate (EC) Berbasis Ekstrak Daun Mindi (Melia azedarach L.) Dalam Mengurangi Kerusakan Beras Akibat Serangan Sitophilus zeamais Motsch Selama Penyimpanan
Abstrak: Rice is the staple food in Indonesia. It needs to be preserved with a good post-harvest handling. Storage is one of the most important stage. At this stage there are often changes in the quality and quantity of stored materials that are influenced by various factors such as storage facilities and warehouse pests. Sitophilus zeamais is a major pest during storage of food grains such rice and maize. Insect control is mostly done by using synthetic insecticides. However, the use of synthetic insecticides should consider their danger due to the fact that they are poisonous to man and domestic animals. One effort to find a replacement for synthetic insecticides are insecticides derived from plants. Mindi (Melia azedarach L.) is a type of tree that grows in tropical and sub-tropical areas and is known as source of plant pesticide. The objectives of this research are to determine the effectiveness of insecticide formulations in the form of Emulsifiable Concentrate (EC) to be applied to the storage of rice and to study the damage of rice during storage due to Sitophilus zeamais infestation. This research consists of two main steps, i.e. preparation stage and insecticide test stage. Parameters observed during storage are number of insect populations (Nt), percent of the holed seeds (%BB), percent weight loss (%KB), % frass, water content and free fatty acid content. Mortality test showed that at concentration of 0 % causing 14 % of insect mortality. It means that in the absence of active ingredient, solvent and emulsifier influence the development of insects. Result of the insecticide test showed that the concentration variation of Melia azedarach L. leaves extract significantly affect (p<0.05) the parameters of rice damage. It was concluded that the most effective concentration of the extact to reduce rice damage is 16 %.
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Judul: Efektivitas Penggunaan Zeolit Dan Bawang Putih Sebagai Zat Penghambat Kerusakan Biologi Pada Jagung Dan Dedak Padi Selama Proses Penyimpanan
Abstrak: The aim of this experiment was to compare the effectiveness of zeolite and garlic as a preventive biological damage caused by insect and mold during the storage of rice bran and corn. The experiment used a complete randomized design, with the factorial model 5 x 4 and 3 replication resepectively. The treatments were P0 (Corn or Rice Bran), P1 (P0 + 1% Zeolite), P2 (P0 + 1% Garlic) and P3 (P0 + 0.15% anti mold commercial). The experiment was conducted for 8 weeks. Variable observed were temperature and humidity, moisture, water activity, total of mold, total and kind of insect. The data were analyzed by Analysis of Variance, and differences among treatments were examined with Duncan (Least Significant Difference). The results showed that the addition of garlic and zeolit at rice bran significantly (P<0.05) decreased total of mold in the sixth week of storage. The commercial anti-mold at rice bran significantly (P<0.05) increased total insect in the eight th week of storage. It is added 1% zeolite and 1% garlic is effective to prevent biological damage caused mold growht at rice bran during storage process and couldn’t effective to corn.
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Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology