Judul: Karakteristik Hasil Fumigasi Amonia dan Daya Tahan Lapisan Finishing Pelarut Air (Waterbased Lacquer) pada Beberapa Jenis Kayu Rakyat
Abstrak: Kayu hutan rakyat memiliki peluang yang tinggi untuk dijadikan produk bernilai tambah yang tinggi, khususnya furniture. Akan tetapi, kayu dari hutan rakyat memiliki penampilan yang kurang menarik (warna pucat dan tidak seragam, serta corak serat kurang menarik) sehingga perlu adanya upaya untuk meningkatkan kualitas tampilan alaminya, salah satunya dengan metode fumigasi amonia. Metode fumigast ini dapat merubah warna dan penampilan kayu menjadi lebih menarik secara alami. Fumigasi amonia dapat digunakan sebagai metode pewarnaan kayu, selain menggunakan staining atau dyeing. Penggunaan metode fumigasi amonia dalam proses finishing kayu juga akan membantu dalam meningkatkan efektifitas dan efisiensi dari proses finishing. Selain itu, bahan finishing yang digunakan sebaiknya aman bagi manusia dan memiliki kekuatan fisik lapisan film yang baik. Salah satu jenis bahan finishing yang aman bagi lingkungan adalah bahan finishing pelarut air (waterbased lacquer). Oleh karena itu, penelitian ini bertujuan untuk mengetahui aplikabilitas pewarnaan alami kayu dengan metode fumigasi amonia dan efektifitasnya terhadap rayap kayu kering (Cryptotermes cynocephalus Light), serta menguji daya tahan lapisan finishing pelarut air (waterbased lacquer) terhadap bahan kimia rumah tangga, hot and cold test, dan cross cut test pada sembilan jenis kayu rakyat terfumigasi dan tanpa fumigasi, delapan jenis diantaranya kayu rakyat yang diteliti, seperti kayu akasia, jengkol, kemang, laban, lamtoro, manglid, puspa, dan watu gunung. Satu jenis yang paling populer bagi konsumen Amerika dan Eropa juga diujikan, yaitu kayu oak. Hasil pengujian menunjukkan bahwa metode fumigasi amonia meningkatkan nilai estetika kayu (tampilan warna dan corak alami) dan keawetan kayu. Selain itu, hasil pengamatan secara visual pada kondisi permukaan kayu terhadap pelunturan bahan kimia rumah tangga dengan interval 1 jam dan 24 jam, dan hot and cold test menunjukkan bahwa bahan finishing pelarut air memiliki daya tahan lapisan yang kuat, sehingga diklasifikasikan ke dalam kelas 10. Pada pengujian daya lekat cat (uji cross cut), contoh uji kayu jengkol terfumigasi dan tanpa fumigasi diklasifikasikan ke dalam Grade 4B dan delapan jenis kayu yang lainnya termasuk Grade 5B.
Keyword: Institut Pertanian Bogor, IPB, Kayu Rakyat, Waterbased, Wood Finishing, Uji Cross Cut, Oak, Bogor Agricultural University

Judul: Karakteristik Hasil Fumigasi Amonia Dan Daya Tahan Lapisan Finishing Pelarut Air (Waterbased Lacquer) Pada Beberapa Jenis Kayu Rakyat.
Abstrak: Wood species from community forests have a high chance to be developed of a high value-added products, particularly furniture. However, these timber forest have a less attractive appearance (pale colors and ununiforms, as well as less attractive fibers). Therefore efforts to improve the quality of its natural appearance are needed. One of the proposed method to improve the quality is ammonia fumigation method can change the color and appearance of wood becomes more attractive naturally. Therefore this method can be used for wood staining. The use of fumigation method in wood finishing process will also help in improving the effectiveness and efficiency of the finishing process. Finishing materials used should be safe for humans also having strength and good film layers. One of which is waterbased lacquer. This study aims to determine the applicability of natural wood staining by ammonia fumigation method and its effectiveness against dry wood termites (Cryptotermes cynocephalus Light). The durability of the finishing layer of waterbased lacquer to household chemicals, hot and cold test, and cross cut tests were also tested. Wood species studied were A. mangium, A. parviflorum, M. kemanga, V. pubescens, L. glauca, M. glauca, S. wallichii, and H. tiliaceus. One of most popular wood species for American and Europe consumers was also tested (the oak wood). The test results showed that ammonia fumigation method increases the aesthetic value of wood (color and pattern look natural) and increases durability of wood. In addition, visual observations on the condition of the finishing lacquer against household chemicals with intervals of 1 hour and 24 hours, and hot and cold tests indicate that the layer of waterbased lacquer have a strong resistance layer, and classified in class 10. Whereas the cross-cut test resistance showed that A. parviflorum wood of fumigation and non-fumigation classified into Grade 4B and eight other species were classified Grade 5B.
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Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model