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 Masa Transisi Kayu Juvenil ke Kayu Dewasa pada Bagian Tengah Batang Sengon (Falcataria moluccana (Miq.) B. Grimes) dan Jabon (Anthocephalus cadamba Miq.)
Abstrak: Sc. Wood is an important forest resources which has been processed in large quantities to meet growing human needs. To meet the increasing demand for wood, wood supplies are able to be taken from fast-growing species planted in plantations and community forests. These fast growing species tend to be harvested in short rotation and have a high proportion of juvenile wood. The objective of this research is to determine the characteristics of juvenile wood in order to use wood Jabon and Sengon properly. The approach of segmented regression model is used to describe the development of juvenile wood to mature wood while non-linear procedures at the level of two orthogonal polynomial equation is used to identify the starting point of the formation of mature wood. To determine the transition of juvenile to mature wood in Sengon and Jabon, samples of two trees with ages 5, 6 and 7 years are taken from the community forest in Sukabumi. Disk with a thickness of 5 cm is taken at a height of 3.5 meters from each sample tree for measuring fiber length, MFA, density and moisture content. Wood moisture content from pith to bark is measure by using gravimetric method. Fiber length and MFA are measured on each circle grows as wide as 1 cm from pith to bark by using maceration and microtome technique. That was an analysis of segmented regression model in radial to fibers and MFA, showing that Sengon and Jabon wood were young wood until the age of 7 years. Fiber length and MFA were the best indicator to determine the transition from juvenile to mature wood, although the transition point varied to their properties. The proportion of juvenile wood on Sengon and Jabon wood at the age of 7 years were respectively 80-100% and 100%.
Keyword: juvenile wood, Microfibril angle

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