Judul: Perhitungan Limpasan Permukaan dan Evapotranspirasi berdasarkan Neraca Air pada Pertanaman Kentang (Solanum Tuberosum L.)
Abstrak: Ketersediaan air merupakan salah satu faktor yang mempengaruhi pertumbuhan, perkembangan serta produksi tanaman kentang. Tanaman kentang cukup banyak dibudidayakan di Indonesia. Tanaman kentang biasa dibudidayakan pada ketinggian lebih dari 1000 m dpl dengan tingkat kemiringan yang cukup tinggi. Kondisi ini mempengaruhi ketersediaan air untuk pertumbuhan tanaman kentang. Tujuan penelitian ini adalah menghitung kehilangan air melalui evapotranspirasi dan limpasan permukaan pada tanaman kentang dengan menggunakan neraca air. Penelitian dilakukan mulai bulan Desember 2009 sampai Maret 2010 di Kebun Percobaan Balitbiogen Pacet-Cipanas, Cianjur. Perhitungan kehilangan air pada tanaman kentang dilakukan dengan pendekatan neraca air dengan persamaan ETat+Rot = θt-1-θt+Pt, dimana θt = kadar air tanah hari ke t, θt-1 = kadar air hari ke t-1, dan ETat+Rot = kehilangan air karena evapotranspirasi aktual dan runoff hari ke t. Evapotranspirasi actual diasumsikan sebesar 4 mm/hari. Hasil penelitian ini menunjukkan bahwa kondisi dimana curah hujan tinggi, terjadi runoff yang besar karena kapasitas infiltrasi dan perkolasi yang terbatas, dan tetap terjadi evapotranspirasi. Hal ini dapat mengurangi kadar air tanah selama masa pertumbuhan tanaman kentang. Kadar air tanah yang lebih tinggi menghasilkan laju pertumbuhan tanaman kentang yang lebih tinggi walaupun jarak tanamnya lebih rapat. Di samping kadar air tanah, ukuran bibit sangat menentukan hasil panen kentang.
Keyword: Potato, Water balance, Evapotranpiration, Runoff, Soil water

Judul: Pendugaan kehilangan air melalui perhitungan neraca air serta analisis pertumbuhan tanaman kentang (Solanum tuberosum L.)
Abstrak: The growth and the production of a plant are determined by favourable environment. Soil is water reservoir and planting area for which the capability to keep the water in the soil will determine the total water that can be used for the plant. Water availability in the soil is used by the plant to fullfil plant’s water requirement such actual evapotranspiration and runoff which can be calculated by using the water balance. The objective of this research is to calculate the potato water loss during the measurement through the water balance and to analyse the effect on potato growth. The result of this research shows that the potato water loss (actual evapotranspiration and runoff) during measurement on 37 days until 73 days after planting is 148-191 mm or 4.6 mm/days, whereas the run off is 28-59 mm or 19-30 % from total water loss potato. The relations between soil water content and the growth rate in each treatment has a different disposed. When the storage of soil water content is high, the growth rate is uncertainly high, and vice versa. The growth rate is of the potato in this research not only influenced by soil water content, but also influenced by other factors that are not observed in this research.
Keyword: 

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.
Keyword: