Judul: Sistem Eksploitasi Karet (Hevea brasilliensiss Muel. Arg.) Di Kebun Gunung Pamela, PT Perkebunan IV Gunung Pamela Tebing Tinggi Deli Sumatera Utara
Abstrak: Tanaman karet (Hevea brasiliensis Muel. Arg.) merupakan tanaman perkebunan yang mempunyai arti sosial ekonomis penting bagi rakyat dan pemerintah Indonesia, Hal ini di- sebabkan karet merupakan komoditi pertanian pemberi devisa besar bagi negara dan merupakan sumber mata pencaharian u- tama bagi jutaan jiwa petani khususnya di Sumatera dan Kalimantan. Pada tahun 1978 diperkirakan sekitar 10 juta orang terlibat dalam produksi komoditi karet di Indonesia (Napitupulu dan Lubis, 1978). Luas areal karet rakyat dan perkebunan di Indonesia 2 324 174 ha (Statistik Karet, 1978), ternyata karet Indonesia terkonsentrasi di Sumatera kurang lebih 72.69%.
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Judul: Pengelolaan Tanaman Karet (Hevea Brasiliensis Muel. Arg.) Dengan Aspek Khusus Penyadapan Di Kebun Batulawang Pt Perkebunan Nusantara Viii (Persero) Ciamis, Jawa Barat
Abstrak: Tanaman karet (Hevea brasiliensis Muel. Arg.) merupakan salah satu komoditi perkebunan yang memiliki arti penting bagi perekonomian Indonesia yang merupakan negara produsen karet terbesar kedua setelah Thailand. Luas areal pertanaman karet di Indunesia menunjukkan peningkatan. yaitu dari 3 495 901 hektar pada tahun 1995 meningkat menjadi 3 601 036 hektar pada lahun 2000. Total produksi karet juga menunjukkan peningkatan, yaitu dari I 573 303 ton pada tahun 1995 meningkat menjadi 1 609 557 ton pada tahun 2000 (Direktorat Jenderal Bina Produksi Perkebunan, 2001).
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Judul: Hybrid solar cells of ZnO nanoparticles/chlorophyll was modified metal ions (Zn2+ and Cu2+ )
Abstrak: Zinc Oxide (ZnO) is a n-type semiconductor with a wide the energy band (Band Gap) is 3.37 eV at room temperature and 3.34 eV at low temperature with a large exiton binding energy is 60 meV. ZnO has been synthesized by hydrothermal method, resulting in a decrease in particle size over the duration of the hydrothermal changes. Crystallographic structure of ZnO were characterized using XRD, has shown the characteristic pattern of a hexagonal wurtzite structure, the crystallite size increases to changes in particle size. Changes in particle size has also led to a change in the absorption peak of ZnO as has been demonstrated posted under test using the optical properties of UV-Vis spectrophotometer. Changes of this uptake has also led to changes in the energy band gap, which increases its band gap energy of the particle size. In electronic applications, especially in solar cells. Chlorophyll is considered less effective, because of their very nature are easily degraded as a result of several reactions which are acid, lighting and temperature. The results of the stability test using a halogen lamp 34 W/m2 for 5 hours, that the substitution of chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form more stable than natural chlorophyll. The characterization of the optical properties, the combination of ZnO / chlorophyll in the form of hybrid films has led to a shift in the absorption region of ZnO becomes more widely from the UV to Visible. ZnO/chlorophyll has absorption range of 350-515 nm, ZnO / Zn-feofitin 332-401 nm and 332-632 nm for Cu-feofitin. The combination of ZnO/chlorophyll and CuSCN as a solid electrolite in hybrid solar cell, a modified chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form a more stable I-V curve. It is characterized by its fill factor value greater than natural chlorophyll. Nevertheless, solar cells with natural chlorophyll has been able to produce higher efficiency values of chlorophyll were substituted.
Keyword: Hydrothermal, ZnO/Chlorophyll modified, Hybrid Solar Cell