The main goal of this research was to quantify the concentrations of total and ammonium N, nitrate, total and soluble P in the water in the presence of Eichhornia crassipes and Salvinia auriculata, which were submitted to two different photoperiods in a 24 hours incubation period in the laboratory. The macrophytes were incubated in plastic vials of approximately 1.5 litters, with a previously p...

Light-absorbing and high-molecular-weight secondary organic products were observed to result from the reaction of glyoxal in mildly acidic (pH=4) aqueous inorganic salt solutions mimicking aqueous tropospheric aerosol particles. High-molecular-weight (500–600 amu) products were observed when ammonium sulfate ((NH4)2SO4) or sodium chloride (NaCl) was present in the aqueous phase. The products fo...

A rhizobacterium isolated from groundnut rhizosphere and identified as Alcaligenes faecalis BCCM 2374 produced siderophore during 24 h submerged growth in modified succinic acid medium (SM) prepared in tap water without deferration. For the optimized production of siderophore in the presence of starch and sucrose, the optimum parameters found were as follows: slight acidic pH (5.5), 35C tempera...

The paper presents the research work done to study the discontinuous bioprocess for the intracellular carotenoidic pigment torularhodin formation with the yeast Rhodotorula rubra ICCF 209. The growth and carotenoid biosynthesis of the yeast Rhodotorula rubra was studied by cultivation in 3.7 L Bioengineering AG lab bioreactor with mechanical stirring at an air flow rate of 200 L/h and agitation...

The main scope of this paper is first of all to verify the efficiency of the flame atomic absorption spectroscopy (FAAS) method for analysis of some trace elements in extracts of fractionation analysis of the gravitation dust sediments. Investigation was oriented to the analysis of some markedly toxic trace elements in the extracts of gravitation dust sediments as well as on efficiency evaluati...

We compared gross N fluxes by N pool dilution in a coarse-textured agricultural soil when N was applied to the soil NH4 C pool by either: (i) mixing a NH4NO3 solution into disturbed soil or (ii) injection of NH3 gas into intact soil cores. The two techniques produced similar results for gross N mineralization rates indicating that NH4 C production in soil was not altered by soil disturbance, me...

Somatic embryogenesis is one of good examples of the basic research for plant embryo development as well as an important technique for plant biotechnology such as medicinally important plants. Single embryos develop into normal plantlets with shoots and roots. Therefore, direct single embryogenesis derived from single cells is highly important for normal plant regeneration. Here we demonstrate ...

This research was conducted with Biscayne marl soil and Krome gravelly loam from Florida and Quincy fine sand and Warden silt loam from Washington to determine ammonia (NH3) volatilization at various temperature and soil water regimes. Potassium nitrate (KNO3), ammonium nitrate (NH4NO3), ammonium sulfate [(NH4)2SO4], or urea were applied to the soil at a rate of 75 kg N ha . Soil water regime w...

A new form of delafossite-type AgCoO2+δ was prepared using ion exchange from Na0.75CoO2 in molten AgNO3-NH4NO3 at 175°C. Its structure was determined by Rietveld refinement from XRD data; it is hexagonal, space group P63/mmc, a = 2.871 and c = 12.222 Å. Its structure differs from previously reported AgCoO2 (R-3m, 3R polytype) by the stacking of Co-O layers; in the new phase the 2H stacking of t...

Green mature fruits of mango cv. SS-1 (Kala Chaunsa) were immersed for 10 minutes in 2.5, 5.0 or 7.5% calcium chloride (CaCl2.2H2O), calcium sulphate (CaSO4.2H2O) or calcium ammonium nitrate {Ca(NH4NO3)2} solutions. A control was also included in which fruits were dipped in fresh water for 10 minutes. The fruits were ripened at ambient temperature (25 ± 3 C) in boxes lined and covered with news...