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This study demonstrates the effects of structural variations of lignins isolated via an organosolv process from different woody and herbaceous feedstocks on their thermal stability profiles. The organosolv lignins were first analysed for impurities, and structural features were determined using the default set of gel permeation chromatography, FT-IR spectroscopy, quantitative 31 P NMR spectroscopy and semi-quantitative 1 H- 13 C HSQC analysis. Pyrolysis-, O 2 - and CO 2 -reactivity of the organosolv lignins were investigated by thermogravimetric analysis (TGA), and volatile formation in various heating cycles was mapped by head-space GC-MS analysis. Revealed reactivities were correlated to the presence of identified impurities and structural features typical for the organosolv lignins. Data suggest that thermogravimetric analysis can eventually be used to delineate a lignin character when basic information regarding its isolation method is available.

Phosphorus (P) binding groups were identified in phytoplankton, settling particles, and sediment profiles by ³¹P NMR spectroscopy from the Swedish mesotrophic Lake Erken. The ³¹P NMR analysis revealed that polyphosphates and pyrophosphates were abundant in the water column, but rapidly mineralized in the sediment. Orthophosphate monoesters and teichoic acids degraded more slowly than DNA-P, polyphosphates, and P lipids. Humic acids and organic acids from phytoplankton were precipitated from the NaOH extract by acidification and identified by ³¹P NMR spectroscopy. The precipitated P was significantly more recalcitrant than the P compound groups remaining in solution, but does not constitute a major sink of P as it did not reach a stable concentration with depth, which indicates that it may eventually be degraded. Since P also precipitated from phytoplankton, the origin of humic-P can not be related solely to allochthonous P.

Long-term application of phosphorus (P) with animal manure in amounts exceeding removal with crops leads to buildup of P in soil and to increasing risk of P loss to surface water and eutrophication. In most manures, the majority of P is held within inorganic forms, but in soil leachates organic P forms often dominate. We investigated the mobility of both inorganic and organic P in profile samples from a noncalcareous sandy soil treated for 11 yr with excessive amounts of pig slurry, poultry manure, or poultry manure mixed with litter. Solution ³¹P nuclear magnetic resonance spectroscopy was used to characterize NaOH-EDTA-extractable forms of P, corresponding to 64 to 93% of the total P concentration in soil. Orthophosphate and orthophosphate monoesters were the main P forms detected in the NaOH-EDTA extracts. A strong accumulation of orthophosphate monoesters was found in the upper layers of the manure-treated soils. For orthophosphate, however, increased concentrations were found down to the 40- to 50-cm soil layers, indicating a strong downward movement of this P form. This was ascribed to the strong retention of orthophosphate monoesters by the solid phase of the soil, preventing orthophosphate sorption and facilitating downward movement of orthophosphate. Alternatively, mineralization of organic P in the upper layers of the manure-treated soils may have generated orthophosphate, which could have contributed to the downward movement of the latter. Leaching of inorganic P should thus be considered for the assessment and the future management of the long-term risk of P loss from soils receiving large amounts of manure.

We present a solid-state nuclear magnetic resonance (NMR) spectroscopy study of the local 31 P and 1 H environments in monetite [CaHPO 4 ; dicalcium phosphate anhydrous (DCPA)], as well as their relative spatial proximities. Each of the three 1 H NMR peaks was unambiguously assigned to its respective crystallographically unique H site of monetite, while their pairwise spatial proximities were probed by homonuclear 1 H– 1 H double quantum–single quantum NMR experimentation under fast magic-angle spinning (MAS) of 66 kHz. We also examined the relative 1 H– 31 P proximities among the inequivalent P1, P2 and H1, H2, H3 sites in monetite; the corresponding shortest internuclear 1 H– 31 P distances accorded well with those of a previous neutron diffraction study. The NMR results from the monetite phase were also contrasted with those observed from the monetite component present in a pyrophosphate-bearing calcium phosphate cement, demonstrating that while the latter represents a disordered form of monetite, it shares all essential local features of the monetite structure.

In areas under intensive livestock farming and with high application rates of animal manure, inorganic and organic phosphorus (P) may be leached from soils. Since the contribution of these P compounds to P leaching may differ, it is important to determine the speciation of P in these soils. We determined the effect of various fertilization regimes on the P speciation in NaOH–Na2EDTA (ethylenediaminetetraacetic acid) and water extracts of acidic sandy soil samples from the top 5 cm of grassland with wet chemical analysis and 31P nuclear magnetic resonance (NMR) spectroscopy. These soils had been treated for a period of 11 years with no fertilizer (control), N (no P application), N–P–K, or different animal manures. Inorganic P was highly elevated in the NaOH–Na2EDTA extracts of the soils amended with N–P–K or animal manures, while organic P increased only in the soil treated with pig slurry. Water-extractable P showed a similar trend. As indicated by 31P NMR, orthophosphate monoesters were the main organic P compounds in all soils. Our results suggest that long-term applications of large amounts of P fertilizer and animal manures caused an accumulation of inorganic P, resulting in an increase of the potential risk related to mobilization of inorganic P in the top 5 cm of these soils.

The kinetic properties of the cytoplasmic and the mitochondrial iso-enzymes of creatine kinase from striated muscle were studied in vitro and in vivo. The creatine kinase (CK) iso-enzyme family has a multi-faceted role in cellular energy metabolism and is characterized by a complex pattern of tissue-specific expression and subcellular distribution. In mammalian tissues, there is always co-expression of at least two different CK isoforms. As a result, previous studies into the role of CK in energy metabolism have not been able to directly differentiate between the individual CK species. Here, we describe experiments which were directed at achieving this goal. First, we studied the kinetic properties of the muscle-specific cytoplasmic and mitochondrial CK isoforms in purified form under in vitro conditions, using a combination of P-31 NMR and spectrophotometry. Secondly, P-31 NMR measurements of the flux through the CK reaction were carried out on intact skeletal and heart muscle from wild-type mice and from transgenic mice, homozygous for a complete deficiency of the muscle-type cytoplasmic CK isoform. Skeletal muscle and heart were compared because they differ strongly in the relative abundance of the CK isoforms. The present data indicate that the kinetic properties of cytoplasmic and mitochondrial CK are substantially different, both in vitro and in vivo. This finding particularly has implications for the interpretation of in vivo studies with P-31 NMR.

Fourier-Transform Infrared （FT-IR） spectroscopy has been used extensively to characterize natural organic matter （NOM）. Absorption bands at 1100-1000 cm^-1 in the FT-IR spectra of NOM have been frequently assigned to alcoholic and polysaccharide C-O stretching or to vibrations of SiO2-related impurities. However, these interpretations do not consider that a strong band associated with P-O bonds of phosphate also appears in the same region. We evaluated the correlation between absorbance in this region and P content of 19 NOM samples from terrestrial, aquatic and plant shoot sources. In the spectra of 10 humic and fulvic acid samples, shoulder to minor bands appeared around 1050 cm^-1. Absorbance intensity at 1050 cm^-1 （Y） was linearly related to P content （X） by the following： Y=4.38X＋0.3 l, with R2=0.90. We did not observe such a close correlation between absorbance and P content in two aquatic NOM samples. Apparently, this is because the aquatic NOM samples were concentrated by reverse osmosis, which would have concentrated not only humic and fulvic acids but also other soluble organic solutes present in natural waters. In the FT-IR spectra of seven dissolved organic matter （DOM） samples obtained from dried plant shoots, broad and/or multiple bands around 1075 cm^-1 were observed with a shoulder at 977 cm^-1. These characteristics were more like those of organic phosphate compounds （such as inositol hexaphosphate）. However, solution 31P nuclear magnetic resonance spectroscopic analysis showed no significant amount of organic phosphate present in these samples.