Judul: Radial variation of wood properties of sengon (Paraserianthes falcataria) and Jabon (Anthocephalus cadamba).
Abstrak: Seven years old Sengon (Paraserianthes falcataria) and Jabon (Anthocephalus cadamba) trees were harvested from plantation forest in West Java, Indonesia aiming to characterize radial pattern of selected physical and anatomical properties. One disk from log section in length of 2m (bottom part) and 6m (upper part) was taken from each tree of the tree stem, the sample from pith to bark (2.6cm x 2.0cm) was prepared from disk. Each sample was divided in 1cm wide segments (segmented ring) numbered from pith to bark. Anatomical parameters and density were measured for each segmented ring to investigate the juvenile and mature pattern of radial variation for each property. Observed patterns were described using three different models: I linearly increase or decrease, II exponential, III lineary equal to intercept. By using measured profiles, a typology of variations was defined from statistical modeling. The pattern of radial variation showed in both species, all properties in vessel elements (vessel frequency and vessel area), fiber length and density in Jabon had model II. Lumen diameter, cell wall thickness and density in Jabon had model I and also for fiber diameter of bottom part in both of species, diameter lumen of upper part Sengon and cell wall thickness of bottom part Sengon. Model III had found in fiber diameter of upper part in both species and lumen diameter of bottom part Sengon.
Keyword: Jabon, juvenile and mature transition, density, vessel element, fiber element

Judul: Penentuan Titik Transisi Kayu Juvenil ke Kayu Dewasa pada Sengon (Paraserianthes Falcataria (L.) Nielsen) dan Jabon (Anthocephalus Cadamba Miq.)
Abstrak: Wood as an important forest resource has been processed in large quantity to fulfill an increasing need of humans. To satisfy the increasing demand for the wood products, the supply of the wood will be come from fast-growing tree species grown on plantation forest and community forest. This fast-growing wood species will tend to be harvested in short age rotations and will contain higher proportions of juvenile wood. The objective of this research is to know characteristics of juvenile and to obtain consistent estimates of transition age from juvenile to mature wood of Sengon and Jabon woods. Segmented modeling approach was used to estimate the age of transition, and the non-linear procedure was employed to identify the juvenile to mature wood transition point. In an attempt to determine the juvenile and mature transition age for Sengon and Jabon, 6 trees were sampled in three age classes (5, 6, and 7 year) from a community forest in Sukabumi. Disks of 5 cm thick were collected at 1.3 meters (diameter breast height) from each tree to determine fiber length, MFA, density, and green-moisture content. Wood density was measured from pith to bark by X-ray densitometry. Fiber length and microfibril angle (MFA) were measured on isolated segmented rings of 1 cm width from pith to bark by visual interpretation on maceration and microtome samples. The segmented regression models and visual interpretation of tangential patterns of variation in fiber length and MFA reveal that juvenility in Sengon and Jabon extends up to 7 years, respectively. Fiber length and microfibril angle appear to be good anatomical indicators of age demarcation between juvenile and mature wood, although maturation age often varies among the properties. The projected figures for proportion of juvenile wood in Sengon and Jabon at age of 7 year are 80–100% and 100%, respectively.
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Judul: Katalis Zink Ferit Tersubstitusi Cu untuk Oksidasi Benzil Alkohol
Abstrak: Katalis berperan dalam menurunkan energi aktivasi. Katalis ZnFe2O4 dan ZnFe2O4 tersubstitusi Cu disintesis menggunakan metode kopresipitasi untuk digunakan dalam oksidasi benzil alkohol. Katalis dicirikan dengan spektrofotometer inframerah (FTIR) dan difraktometer sinar-X. Spektrum FTIR menunjukkan puncak serapan dari ikatan Zn-O dan Fe-O masing-masing pada rentang 559‒575 cm-1 dan 419‒447 cm-1. Difraktogram menunjukkan terbentuknya fase tunggal Zn0.6Cu0.4Fe2O4 pada katalis ZnFe2O4 tersubstitusi Cu 20%. Benzil alkohol dioksidasi dengan sistem refluks. Konversi benzil alkohol meningkat dengan meningkatnya suhu. Kadar benzaldehida yang dihasilkan dengan katalis ZnFe2O4 tersubstitusi Cu 20% lebih tinggi dibandingkan dengan katalis ZnFe2O4 yang tidak tersubstitusi dan yang tersubstitusi Cu 60 dan 80%. Hal tersebut menunjukkan bahwa katalis ZnFe2O4 tersubstitusi Cu 20% memiliki kinerja yang lebih baik dalam oksidasi benzil alkohol menjadi benzaldehida dengan kadar benzaldehida 8.763%.
Keyword: Benzil alkohol, katalis, oksidasi, ZnFe2O4