Judul: Pengamh cara inkubasi, pengapuran dan pemupukan fosfor terhadap tanaman jagung ( Zea ntays L. ) pada tanah Hapludult ( Podsolik ) Gajrug
Abstrak: The aim of this research are to study the methods of phosphorus fertilization on any lime doses and the lime and phosphor incubation method on corn plant ( Zen mays L. ) on Hapludult ( Podsolik Gajrug ). Experimental design used in this research is Split Plot Design with lime factors on 4 grade as follow KO= Ox, K1= 25%, K2= 50% equal to exchangeable-Al, 100% equal to exchangeable-At, and with phosphorus factors on 1.24 g and K3 = TSPIpot, 3.37 g rock phosphatelpot, and 1.04 g mono-calcium phosphatelpot equal to 50 ppm P application. Initial fertilizer used are ZA with 100 ppm N doses (2.4 g ZAIpot) and KC1 with 100 ppm K doses (1 g KCVpot). Duncan test was established whether to understand the effect of each treatment or combination of some treatment. The lime treatment which was done earlier then incubated for one week are significantly higher to the lime and phosphorus fertilization that were done at the same time but incubated for two weeks on the corn dry mass and pH. Content and uptake of phosphorus in the second incubation are higher than the first incubation. Lime increasing doses significantly increase the corn dry mass, pH and phosphor uptake but decrease the exchangeable-Al. The treatment of 25% lime equal t o exchangeable-Al cause the highest plant phosphorus content compare to no lime, 50% lime application, and 100% lime application equal to exchangeable-Al treatment. Lime treatment did not give significant effects to the CEC and available P. The phosphate mono-calcium treatment significantly higher than TSP and rock phosphate on pH value. The phosphate mono-calcium treatment cause higher plant phosphorus content and phosphorus uptake compare to the TSP and rock phosphate treatment. Treatment of TSP, rock phosphate and phosphate monocalcium were not significantly different on corn plant dry weight, exchangeable Al, CEC and available phosphate. The treatment of 100% lime equal to exchangeable-& that was done earlier then add by TSP significantly higher than other combination treatments to the corn dry mass. The treatment of 100% lime equal to exchangeable-& that was done earlier then add by rock phosphate significantly increase pH value higher than other combination treatments. Combination treatment on 100% lime equal to exchangeable-& with TSP that were done on the same time gave the lowest pH value compare to other combination treatment.
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Judul: Pengaruh Pemberian Fosfat Alam Terhadap Perubahan Sifat Kimia Tanah, dan Kadar Hara Pada Tanaman Jagung (Zea mays)
Abstrak: The utilization of acid soil for agriculture faced several obstacles, including P deficient. It is because P ions sorbed by various soil components, such as Fe-Al ions, and Fe-Al hydrous oxides. One of the efforts made to overcome this problem is the use of natural phosphate in acid soils. This study aims to determine the effect of natural phosphate fertilizers in soil chemical properties and nutrients rate in plant of Latosol (Oxyc Dystrudept) Darmaga. Experimental design used in this study was a randomized design with a single factor, named P fertilizer. Source of P fertilizer used in this study is a natural phosphate and SP-36. Treatment dosage of P fertilizer are, control I (0%), control II (N + K), Std 100% (N+K+SP36), RP 50%, RP 100%, RP 150%, RP 200%, (N + K 50%) + RP 50%, and (N + K 50%) + RP 100%. The results showed that the phosphate fertilizer did not significantly affect soil pH, exchangeable-Al, available-P, exchangeable-Ca, and exchangeable-Mg. phosphate fertilizer have significantly affect only in exchangeable-K. Meanwhile, phosphate not significantly affect the rate of Mg, K, Ca, P and N. Rock phosphate’s application significantly affected the growth of maize on 4 week after planting (MST) and 6 MST. Rock phosphate’s application did differ significantly on increasing cob with husk’s weight and cob without husk’s weight. But rock phosphate’s application did not differ significantly on total weight of stover. The highest percent of crop value in treatment who give rock phosphate fertilizer there is in treatment of RP 150% with 158.1%, and the lowest percent of crop value there is in treatment of (N+K 50%) + RP 50% with 98.6%, and lowest in all treatment there in treatment of Control I with 74.7%. From result of crop value can get a conclusion that rock phosphate fertilizer is better than standard fertilizer (SP36).
Keyword: acid soil, maize, phosphate

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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