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Ammonia (NH 3 ) volatilization losses following surface application of urea and three enhanced efficiency nitrogen (N) containing fertilizers (EEFs) were compared in six thinned mid-rotation loblolly pine ( Pinus taeda L.) stands across the southern United States. All fertilizer treatments were labeled with 15 N (∼370‰, 0.5 AP) and applied during two different seasons (spring, summer) in 2011 to open chamber microcosms. Individual microcosms were sampled 1, 15 and 30 days after fertilization to estimate remaining 15 N. Losses of fertilizer N were determined using a mass balance calculation. Significantly less N loss occurred following fertilization with EEFs compared to urea after all sampling days for both seasons. Because root uptake was eliminated in the microcosms and there was no leaching of 15 N below the microcosms, the most likely loss pathway of the 15 N from the microcosms was NH 3 volatilization. There were generally no differences among the individual EEFs. Following spring application, the mean NH 3 volatilization during the 30 day experiment ranged from 4% to 26% for the EEFs compared to 26–40% for urea. In summer, mean NH 3 volatilization for EEFs ranged from 8% to 23% compared to 29–49% for urea. This research highlights the potential of EEFs to reduce loss of fertilizer N in forest systems, potentially increasing fertilizer N use efficiency in these pine plantations. [ABSTRACT FROM AUTHOR]

Four ruminally and duodenally cannulated Suffolk weather lambs (34.5 ± 2.0 kg initial BW) were used in a 4 x 4 Latin square-designed experiment to examine the effects of ruminal protein degradability and supplementation frequency on site and extent of digestion in lambs consuming a low-quality forage diet. Wethers were fed a basal diet of mature crested wheatgrass hay (4.2% CP) for ad libitum consumption plus 1 of 4 supplements: 1) a high RDP supplement provided daily (RDP-D), 2) the high RDP supplement provided on alternate days (RDP-A), 3) a high RUP supplement provided on alternate days (RUP-A), or 4) a 50:50 mixture of the RDP and RUP supplements, provided on alternate days (MIX-A). Forage OM, N, NDF, or ADF intakes were not affected by treatment. True ruminal OM digestibility was greater (P < 0.001) for MIX-A lambs compared with other treatments. True ruminal N digestibility was less (P < 0.01) in RUP-A lambs compared with other treatments. Ruminal digestibilities of NDF and ADF were greater (P < 0.01) for MIX-A lambs compared with other treatments. There was a treatment x hour interaction (P < 0.001) with a delay in peak concentrations within the RDP-A lambs. However, lambs supplemented with RUP had less (P < 0.001) ruminal ammonia concentrations compared with RDP-D lambs, with RUP-A lambs exhibiting the least concentrations and least variation over time. Ruminal urease activity was not affected by treatment. Microbial N flow was not affected by treatment; however, there was an increase (P = 0.004) in microbial efficiency for RDP-D lambs. Alternate day protein supplementation with a mixture of RDP and RUP may improve digestibility in lambs consuming low-quality forage, which may be related to decreased fluctuation in ruminal ammonia concentrations as a result of greater endogenous N recycling. [ABSTRACT FROM AUTHOR]

This study reported the effects of post-treatment processing of ammonical copper lignin complex A treated wood on subsequent retention level of preservative and copper content. Wrapping for 96 hours gave the best protection to wood in ground contact for 36 months, followed by steaming at 50 °C. [ABSTRACT FROM AUTHOR]

The abundance and diversity of archaeal ammonia monooxygenase subunit A (amoA) genes from hydrothermal vent chimneys at the Juan de Fuca Ridge were investigated. The majority of the retrieved archaeal amoA sequences exhibited identities of less than 95% to those in the GenBank database. Novel ammonia-oxidizing archaea may exist in the hydrothermal vent environments. [ABSTRACT FROM AUTHOR]

Metal-induced crystallization (MIC) process was employed to crystallize hydrogenated amorphous silicon carbide (a-SiC:H) films deposited by PECVD on n-type Si substrate. To optimize the crystallization process, Aluminum thin films of different thicknesses were deposited on a-SiC:H films which were then annealed at 600 °C in N2 environment for 1 h. UV–visible spectrophotometer, atomic force microscopy (AFM) and hall measurement system were used to characterize the films. It was observed from the UV–visible spectrum that the films crystallized using higher Al thickness show absorption in the visible range whereas the samples crystallized with lower Al thickness did not show absorption in the visible range but shows large absorption above the bandgap of the material. Considering UV–visible and Hall measurement data it can be concluded that the sample crystallized with 50 nm of Al can be a good candidate for SiC–Si hetero-junction solar cells. [ABSTRACT FROM AUTHOR]

Thin films and crystalline powder of PbI2 intercalated with ammonia or pyridine have been studied by optical absorption, Raman scattering, photoluminescence, FTIR spectroscopy and thermo-gravimetric analysis. Ammonia intercalated PbI2 shows an increased optical band gap, of about 0.6 eV, with an intense broad emission band peaking at about 2.3 eV as signature in the photoluminescence spectrum. The intercalation of PbI2 with ammonia is noticed in the Raman spectrum by the appearance of new lines situated in low frequency range. The D3d coordination geometry of Pb2+ in the PbI2 crystal is reduced by compression to orthorhombic one, the distribution of the electronic states in valence band is also changed. Thus, the top of the valence band undergo a deformation inducing a weakness of the interaction between the lead and iodine ions within a layer. Also the PbI2 intercalated with pyridine is featured by optical and vibration properties different that of pure crystalline powder. Finally, the intercalation of PbI2 with different molecules changes the basic semiconducting properties of the crystal. Thermal analyses and infrared absorption spectra have been used to study the desorption of guests species from PbI2 in order to evaluate the stability range and morphological changes with temperature. [ABSTRACT FROM AUTHOR]

Abstract: The electrolysis of ammonia (NH3) was studied as a remediation process for the removal of ammonia from wastewater, with the advantage of producing hydrogen while returning clean water to the environment. An electro-catalyst able to support the electro-oxidation of ammonia at low concentrations was designed. Two substrates were tested, Raney nickel and carbon fiber. Carbon fiber was found to be a better substrate for the electrolysis of ammonia at low concentrations. The performance of noble metals such as Rh, Pt and Ir, electroplated on the carbon fiber substrate was also evaluated. Rh–Pt–Ir and Pt–Ir on carbon fiber substrate were found to be the most promising electrodes for the electrolysis of ammonia at low concentrations. The maximum ammonia conversion was 91.49±0.01% for a typical concentration of ammonia found in sewage water and the Faradaic efficiency was 91.81±0.13% on the selected anode. [Copyright &y& Elsevier]

Abstract: A mechanism for the formation of the target compound Al4N12H24 from triethylaluminum and ammonia is proposed and studied theoretically at both the PM3 and RHF/6-31G(d,p)//PM3 levels. The highest activation energy during the course of the reactions is about 40kcal/mol at both levels of theory. Ammonia molecules are shown to play a crucial role in the formation of the target molecule and the reactions are expected to speed up with increased concentration of ammonia, based on the mechanism proposed in this paper. On the other hand, a high concentration of NH3 molecules may increase the concentration of defects and undesired products containing fused rings. [Copyright &y& Elsevier]

Background/Aims: It has been proposed that, in acute liver failure, skeletal muscle adapts to become the principle organ responsible for removal of blood-borne ammonia by increasing glutamine synthesis, a reaction that is catalyzed by the cytosolic ATP-dependent enzyme glutamine synthetase. To address this issue, glutamine synthetase expression and activities were measured in skeletal muscle of rats with acute liver failure resulting from hepatic devascularization. Methods: Glutamine synthetase protein and gene expression were investigated using immunoblotting and semi-quantitative RT-PCR analysis. Glutamine synthetase activity and glutamine de novo synthesis were measured using, respectively, a standard enzymatic assay and [13C]-nuclear magnetic resonance spectroscopy. Results: Glutamine synthetase protein (but not gene) expression and enzyme activities were significantly up-regulated leading to increased de novo synthesis of glutamine and increased skeletal muscle capacity for ammonia removal in acute liver failure. In contrast to skeletal muscle, expression and activities of glutamine synthetase in the brain were significantly decreased. Conclusions: These findings demonstrate that skeletal muscle adapts, through a rapid induction of glutamine synthetase, to increase its capacity for removal of blood-borne ammonia in acute liver failure. Maintenance of muscle mass together with the development of agents with the capacity to stimulate muscle glutamine synthetase could provide effective ammonia-lowering strategies in this disorder. [Copyright &y& Elsevier]

Condensed tannins have formaldehyde gas-scavenging ability. Tannins consisting of phloroglucinol-type A-rings, such as prodelphinidin and procyanidin, had higher formaldehyde-scavenging ability than those consisting of resorcinol-type A-rings, such as prorobietinidin and profisetinidin. This ability was markedly improved by ammonia treatment. The increase in formaldehyde-scavenging ability was especially notable in the case of condensed tannins with a high ratio of pyrogallol-type B-rings, such as prorobietinidin and prodelphinidin. To clarify the factors affecting improvement of the formaldehyde-scavenging ability by ammonia treatment, the reaction behavior of condensed tannins during ammonia treatment was studied. Analyses using 13C-NMR and on-line methylation pyrolysis/gas chromatography/mass spectrometry revealed that on treatment of condensed tannins with ammonia, amino-substitution at C-4′ of the pyrogallol-type B-ring occurred to form a 4′-amino-3′,5′-dihydroxybenzene-type B-ring. It can be assumed that the introduction of a 4′-amino-3′,5′-dihydroxybenzene-type B-ring into the tannin molecule results in improved formaldehyde-scavenging ability. [ABSTRACT FROM AUTHOR]

This paper studies the effects of high ammonia emissions and nitrogen deposition on tree growth. Wood cores of 125 Norway spruces were analysed along a transect (800 m) from forest edge to forest interior. The forest edge was exposed to a strong ammonia emission source (poultry farm, less than 50 m). Atmospheric nitrogen bulk deposition, ammonia concentration, soil solution concentration, soil nutrient content, foliar N concentration and C/N ratio of the humus layer were measured at five plots along the transect. The tree growth increment of two clusters of trees close to the forest edge and forest interior was compared. The results indicate extremely high nitrogen load at the forest edge. All nitrogen variables show an `edge effect' with increasing values from forest interior to the forest edge. The growth of nitrogen-influenced spruce trees generally increases. Trees with excessive long-term nitrogen load appear to loose increment after a long-term nitrogen impact. The average gain of increment at the edge appears to be related to the amount of nitrogen emission. [ABSTRACT FROM AUTHOR]

Wood treated with CCB (chromated copper borate) has an expected service life of 20?50 years, depending on conditions of service and method of treatment. After this period, treated wood is discarded as special waste. Due to toxic elements (Cu, Cr, and B) in such treated wood, burning and landfill disposal are not considered as environmentally sound solutions. Chemical extraction seems more promising. The principle of the method is to convert fixed biocides in wood into soluble form and leach them out of the wood. In order to elucidate this process, copper(II) sulfate, potassium dichromate, and CCB-treated samples were leached using five different agents, namely, water, an aqueous solution of oxalic or acetic acid, and an aqueous solution of oxalic or acetic acid with ammonia. Afterwards, the amounts of leached copper and chromium were determined. In a parallel experiment, electron paramagnetic resonance measurements of wet- and dry-leached and unleached samples were performed in order to determine the paramagnetic complexes that were formed. The highest chromium leaching was achieved with the aqueous solution of oxalic acid, as chromium was converted into water-soluble chromium oxalate. While the mixture of oxalic acid and ammonia resulted in the highest copper leaching, EPR observation revealed that in this case water-soluble complexes of copper, oxalic acid, and ammonia were formed. We found out that oxalates formation is not the only mechanism responsible for copper or chromium leaching. High acidity may play an important role too. [ABSTRACT FROM AUTHOR]

The diacetonides of 9α,14α-epoxy-14-deoxy-20-hydroxyecdysone and 14α-hydroperoxy-14-deoxy-20-hydroxyecdysone have been obtained by the interaction of diacetonide of 20-hydroxyecdysone with a solution of lithium in liquid ammonia and following treatment with ammonia chloride and atmospheric oxygen. [Copyright &y& Elsevier]