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Summary  

We discuss the concentration factor methods for determination of jumps in terms of spectral data. The results are relative to the classical Lukcs Theorem and some recent results obtained by A. Gelb, E. Tadmor and F. Mricz.

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The detection and evaluation of changes in vegetation patterns is a prerequisite for monitoring programs. The Swiss mire monitoring program aims to assess the changes in mire vegetation in order to examine the efficiency of the management measures. A promising way to explore and detect vegetation structure and vegetation change is the application of predictive vegetation mapping that combines image classification and predictive habitat distribution models. These models deal with predictor variables derived from remotely sensed spectral data and from environmental variables such as a digital surface model (DSM). Low accuracy of environmental data to predict vegetation at the local scale is due to the difficulties to capture dominant fine-scale enironmental gradients. Using high resolution spectral and topographical data sets of 50 cm pixel size and below, the study presented here aims to improve the simulation of local-scale vegetation properties.

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The impact of decreasing plant diversity on terrestrial ecosystem productivity remains controversial. Recent studies generally suggest that diverse plant communities are more productive than depauperate versions. However, there is less agreement as to whether this is caused by the number of species present, the identities of the species present, the number of functional groups that these species make up, or by which functional groups are represented. This study evaluates whether relationships between plant diversity and productivity in northern mixed grass prairie are dependent on (a) the diversity measure used (species richness vs. functional richness), (b) the productivity measure utilized, or (c) the scale of observation. We collected plant diversity and productivity information over circular plots of 0.5 m diameter during the summer of 1998, then used a spatially nested sampling design to scale each property and their relationships to 2.5 m, 10 m and 50 m sampling resolutions. Observed diversity-productivity relationships were dependent on all of the above factors. Richness-productivity relationships were found to be mostly asymptotic at all observational scales. The presence of particular species, and functional groups, alone or in combination all had significant effects on productivity at the plot (0.5m) level, but not at coarser resolutions. These results were consistent with those of other studies, and suggest that the higher productivities of diverse grassland plots in our grassland site might result from the effects of diversity and the presence of productive species. The lack of species effects at coarser resolutions suggest other mechanisms are responsible for such relationships at these scales.

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On the oximine complexes of transitionmetals

Part CXIX. Thermal and spectral studies on Ni(Diox.H)2 type chelate compounds

Journal of Thermal Analysis and Calorimetry
Authors: Cs. Várhelyi Jr., G. Pokol, Á. Gömöry, A. Gănescu, P. Sohár, G. Liptay, and Cs. Várhelyi

Abstract  

Fourteen chelates of the type [Ni(II)(Diox.H)2], ((Diox.H)2: various α-dioximes) have been studied by means of FTIR, NMR, MS data and various thermoanalytical methods (TG, DTA, DTG, DSC). In some cases kinetic parameters of the thermal decomposition of the complexes were also calculated using Zsak’s ‘nomogram method’. The mechanism of the decomposition processes was characterised on the basis of mass spectra.

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derivatives that belong to a class of coordination compounds of current interest for their insulin-mimetic properties have been synthesised and characterised. Spectral data indicate a square pyramidal stereochemistry for complexes and a chelate coordination

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times and mass spectral data of the reference standards. 3.1.2. Identification of Components through Investigating Literatures 3.1.2.1. Organic acids

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of 5–70°, a step width of 0.05° and an acquisition time of 2 s on each step. Synthesis of the complexes and spectral data Synthesis of VO(naringin) 2 (H 2 O) 8 ( 1 ) A saturated solution of

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2 ] + parent ion. Scheme 1 The possible unimolecular reaction pathway in CVD process constructed based on mass spectral data Molecular structure

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-139. Qualitative (Comparative) analysis by near infrared spectroscopy 135 139 Kaffka, K. J. & Gyarmati, L. S. (1996): Reduction of spectral data for rapid quality evaluation

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established for the rapid chemical profiling in leaves. A total of 13 flavonoids were simultaneously characterized, and their proposed characteristic product ions and fragmentation pathways were investigated. The results provided valuable mass spectral data

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