Judul: Transmisi radiasi surya dan koefisien pemadaman tajuk tanaman kentang (solanum tuberosum L.) di Galudra, Cipanas-Jawa Barat
Abstrak: Potatoes are one of the important vegetable crops in Indonesia. In general, potato can grow in the tropics and subtropics. In an effort to develop this plant in Indonesia is necessary to study the environmental conditions suitable for the growth and development, in relation to climate variables. One of the important climatic variables is the solar radiation. The study was conducted in the Village of Galudra, Cipanas, West Java with the aim to find the proportion of radiation transmitted by the potato crop and canopy extinction coefficient. Transmission of radiation is the radiation energy that passes on the ground under the canopy while the canopy extinction coefficient is the rate of reduction of radiation by the plant canopy. Transmission of radiation is a function of LAI, where LAI higher LAI will result in reduced transmitted radiation. The canopy extinction coefficient and radiation interception (Qint) increased with LAI. This is because the ability of canopy to cover the soil surface decreases by which so much radiation escapes into the ground under the canopy.
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Judul: Efisiensi penggunaan radiasi surya pada tanaman kentang (Solanum tuberosum L.) varietas Granola di Galudra, Cianjur
Abstrak: The production of potatoes crop is influenced by solar radiation. Radiation use efficiency is a gradient of relationship between cumulative intercepted radiation and total dry matter. The aim of this experiment is to measure intercepted solar radiation and total dry matter to find out radiation use efficiency (RUE). An experiment was conducted in April-Juni 2010 at Galudra, Cianjur. The intercepted radiation was calculated by equation of Beer’s law, Qint = Qo (1-t), with t = 0,0393 e1,3718LAI and Qo = solar radiation measured at Stasiun Klimatologi Pacet. The result shows that the intercepted solar radiation by crop canopy increased with increased LAI, and therefore total crop dry matter. Radiation use efficiency of potato crop in Galudra was 1,55 gMJ-1 (above ground biomass), and 4,49 gMJ-1 (total biomass, including dry tuber).
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Judul: Characterizations of low alloy steel sae 4422  plated with chromic acid (Cro3)
Abstrak: Characterizations of low alloy steel SAE 4422 plated with chromic acid (CrOrO3) was use Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), RD),Energy Dispersive Analysis of X-Ray (EDAX), Hardness Test and Roughness Test. Microstructures analysis exhibits cracks and grain boundaries microcracks as a characteristics of chrome metal found at plating metal. Perlite and Ferrite as grains of steel found at base metal with grain boundaries around it. Phase analysis of plating metal appropriate to chrome metal with lattice constant (a) is 2.559 Å and phase analysis of base metal appropriate to iron ferrite with lattice constant (a) is 3.318 Å. Both plating and base metal have cubic system. Chemical analysis of plating metal at surface section exhibits that cracks area have highest value of carbon element compare with grains and grains boundaries area. While chemical analysis of base metal at cross section exhibits that perlite have highest value of carbon element compare with ferrite and grain boundaries. The hardness value of plating metal at surface section and cross section are 753 and 637 VHN. While, the hardness value of base metal and interface area at cross section are 205 and 373 VHN. The roughness value at measurement points of chrome surface for as received sample are 0.445 μm. Observation used Optical Microscopy and Scanning Electron Microscopy exhibits surface irregularities combine to form surface texture of plating metal at surface section.
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