Judul: Pengaruh Pemupukan Boron terhadap Kualitas Buah Manggis (Garcinia mangostana L.).
Abstrak: The objective of this research was to study the effect of boron application on fruit quality of mangosteen, especially the scaring and yellow latex incidence (gamboges). The research was conducted at mangosteen orchard Cicantayan Sukabumi, Laboratory Centre for Tropical Horticulture Studies (PKHT) IPB, and Post Harvest Laboratory of Agronomy and Horticulture IPB on November 2011 to April 2012. The research was arranged in Randomized Complete Design with one factor of treatment: Boron dose (B2O3). There were four doses of fertilizer used consisted of : the control with no fertilizer application B2O3, 15, 30, and 45 g B2O3 / plant. The results of this research showed that Boron application have significant effect on gamboges on pericarp of the mangosteen fruit when compared to controls. However, Boron application significantly increase fruit weight and diameter as well as totat soluble solids content, but there is no different effect of doses between 15, 30, and 45 g/ plant. This treatment is also have no effect on other components of the mangosteen fruit qualities such as hardness of fruit, fruit weight and skin thickness, total of titrable acid, and vitamin C in the mangosteen.
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Judul: Pelapisan Manggis Segar (Garcinia mangostana L.) dengan Lilin Lebah, Hormon Giberelin, dan Benomil
Abstrak: Mangosteen (Garcinia Mangostana L) is one of fruit which has high economic value. The constraint of Mangosteen selling is wilt speed of fruit calyx, that could be assumed as decrease of quality by consumer thinking. Because of that condition, selling activity also decreased. One of way of to lengthen the fruit shelf-life is coating. Coating has known as a protecting substance of food, reduce the transpiration of product, and protect products from microbial contamination. So, the constrain which faced aspecially for seller and exporter for maintain mangosteen quality and freshness can be solved. The purpose of this research are knowing maturity degree of mangosteene which use as a raw material for next research that is knowing organoleptyc and physical effects of coating consentrations during storage. This research consists of two phases. Phase I decide of maturitie’s degree (2 , 3, and 4) and temperature’s storage (room and cool). Phase II decide consentration of coating agent. Types of concentration agent are consisted two levels of beeswax (4 and 6%), three levels of giberelic acid (5, 10, and 15 ppm), and two levels of benomyl (500 and 1000 ppm). The parameters were observed during storage involve physical parameter (visual sheath, weight reduce, husk hardness, and husk colour) and organoleptyc test (kernel and fruit husk colour, ratch vision, taste, and flavour). Based on regretion analysis result visual sheath and weight reduce, the third maturity degree has slope value (2,443 and 0,008). that result have smaller vvalue than others. Result of that maturitie’s organoleptyc test was accepted by consumer in cool storage temperature until 12 days. While room storage until 9 days. The 6% concentration of beeswax coating has smaller slope value at parameters sheath, reduce weight, and hardness husk than others (2,109; 0,007; 0,017). Not only that parameters but also organoleptyc test knowed that consentration had higher accepted consumer than others. The 10 ppm concentration of giberelic acid coating has smaller slope value at parameters sheath, reduce weight, and hardness husk than others (2,453; 0,001; 1,579). According organoleptyc test knowed that consentration had higher accepted consumer than others. The 1000 ppm concentration of benomyl coating has smaller slope value at parameters sheath, reduce weight, and hardness husk than others (2,237; 0,009; 0,179). Not only that parameters but also organoleptyc test knowed that consentration had higher accepted consumer than others.
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Judul: Best Difference Equation Aproximation to Duffing 's Equation
Abstrak: Persamaan Duffing merupakan persamaan yang sering muncul sebagai model masalah sistem ayun mekanis atau pada masalah rangkaian listrik. Umumnya penyelesaian persamaan ini secara numerik memberikan hampiran dengan gala! yang tinggi, seperti dengan metode Runge-Kutta. Tulisan ini mengkonstruksi suatu persamaan beda untuk menghampiri persamaan Duffing tersebut. Penyelesaian dari persamaan beda ini melibatkan fungsi-fungsi eliptik Jacobi. Berdasarkan penyelesaian ini diperoleh basil bahwa penyelesaian hampirannya persis sama dengan penyelesaian analitiknya. Penyelesaian analitik yang diperolehjuga melibalkan fungsi-fungsi eliptik Jacobi.
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