DFG

The authors thank the german research community (DFG) for the support of the presented investigations whieh were realized inside the Special Research Area 326, named, J rocess Integrated Quality Control with Quality Information System for Metallic Parts in Mechanical Engineering, and special thanks to the scientific bilateral project between Brazil and Germany supported by the CNPq, KFA and DLR to realize the presented investigations in advanced radioscopy and tomography. 

The authors thank the German Research Community (DFG) for their assistance within their investigation project Beam-Material-Interaction During Laser Beam Machining". 

This researeh has been supported by the Deutsehe Forsehungsgemeinsehaft (DFG) under Grant No. 435-BUL-l 13/45. 

Parts of the calculations have been performed on the Cray systems of the Centro Interdipartimentale di Calcolo dell Universita di Trieste and of CINECA at Bologna. This work was supported by the Deutsche Forschungsgemeinschaft (DFG). The authors are also indebted to Prof. P. Fulde of the Max-Planck-Institut fiir komplexe Systeme, Dresden for support. 

Acknowledgement. The author would like to thank the DFG and the Ponds der Chemischen Industrie for continued financial support. 

The research reported here was supported by the Deutsche Forschungsgemein-schajt (DFG), the Fonds der Chemischen Industrie and the State of North Rhine Westphalia (Bennigsen Foerder award for M. K.). Thanks are due to all the students who did the experimental work and whose names appear in the references. Thanks are also due to Prof Dr. G. Henkel (University of Paderborn), and especially to Prof Dr. J.D. Corbett (Ames, lA, USA). 

We thank Petra Lembke and Petra Heese for assistance during the cell wall analysis. We thank Dr. U. Sonnewald for the generous gift of the transgenic invertase plants. This work was supported by a DFG grant to SHB (HO 1605/1-2). 

We like to thank Dr. H. Kusserow and Dr. W. Schafer for providing the PCR-primers and Dr. M. Zimmermann for help with the molecular genetic experiments. Financial support from the German Research Council DFG, from the German Academic Exchange Service DAAD, and from the Land Nordrhein-Westfalen is gratefully acknowledged. 

The work from the author s laboratory has been supported by DFG Gr 480/10. 

This shows that there are now oscillating dipoles at frequencies (coi + CO2) and (cOi — CO2), which give rise to SFG and difference frequency generation (DFG), respectively. When C0i = C02, Eq. (5.7) becomes ... 

We would like to express our gratitude to all the collaborators who have contributed to the work described in this chapter. We are also indebted to M. T. M. Koper for a thorough reading of the manuscript and for suggesting a number of improvements. The authors gratefully acknowledge the financial support received from the ANR (in the framework of Chaire d ExceUence (E.S.) and the Carbocell and MDM projects (F.M.)), RFBR, DFG, and BMBF. 

The multi-residue method DFG was intended to be used in state enforcement laboratories or in private contract or food industry laboratories. It was aimed initially only at plant materials and water and included a relatively large number of pesticides which are amenable to GC. 

Another extension of the DFG S19 method was achieved by applying it successfully to foodstuffs of animal origin such as whole milk and egg, muscle meat, offal, fat and honey. Depending on water and fat content, either water-acetone (e.g. for milk, meat, possibly egg and honey) or acetone-acetonitrile (e.g. for offal, egg, fat) solvent extraction is preferable. When high fat or oil contents in the raw extract are expected,... 

A further extension of the DFG S19 method was achieved when polar analytes and those unsuitable for GC were determined by LC/MS or more preferably by liquid chromatography/tandem mass spectrometry (LC/MS/MS). Triple-quadrupole MS/MS and ion trap MS" have become more affordable and acceptable in the recent past. These techniques provide multiple analyte methods by employing modes such as time segments, scan events or multiple injections. By improving the selectivity and sensitivity of detection after HPLC separation, the DFG S19 extraction and cleanup scheme can be applied to polar or high molecular weight analytes, and cleanup steps such as Si02 fractionation or even GPC become unnecessary. 

Another successful adaptation of the fully extended DFG S19 approach is the determination of, e.g., fenpyroximate in all type of berries by LC/MS/MS with APCI monitoring of positive ions directly in the S19 raw extract, and further the determination of trifluralin by LC/MS/MS with APCI monitoring of negative ions after performing a short SPE cleanup on an ion-exchange material. Similar approaches have used CC/MS/MS for, e.g., fenpropimorph and kresoxim methyl in St. John s Wort and peppermint. 

The methods EN 1528 1996 and EN 12393 1998 comprise a range of old multiresidue methods of equal status, which are widely accepted throughout Europe. These are, e.g., the Luke method and the German Deutsche Forschungsgemeinschaft (DFG) methods S8 and S19 ° (all based on extraction with acetone), the Association of Official Analytical Chemists (AOAC) method 970.52 (using acetonitrile extraction and liquid-liquid partition combined with Horisil column cleanup) and the Dutch ethyl acetate extraction combined with GPC. All methods have been subjected to inter-laboratory studies, although not with all pesticide/matrix combinations, which would be impossible to achieve. 

To reduce the effort, another validation procedure is used for extension of the German multi-residue method to a new analyte. Actually, more than 200 pesticides can be analyzed officially with this method, which is the up-to-date version of the better known method DFG SI9. A typical validation is performed by at least three laboratories, which conduct fortification experiments at the same three levels with at least four representative matrices. These representative matrices are commodities with high water content (e.g., tomato), fruits with high acid content (e.g., lemon), dry crops (e.g., cereals) and commodities with high fat content (e.g., avocado). 

The analysis of azole compounds is becoming increasingly important. For the regulation of their residues, the multi-method Deutsche Forschungsgemeinschaft (DFG) S19 is used throughout Europe. Within the last few years, this method has been validated for many new azole fungicides in various crop matrices. The multi-residue method and the most important procedural details for the detection and determination of azole compounds are described below. Some important properties are shown in Table 1. 

Multi-residue Method S19 of the DFG Manual,including Cieanup Procedure Xll-6 (gel-chromatographic cleanup), has been used successfully in many laboratories because of its broad applicability for the gas-chromatographic determination of pesticide residues in foodstuffs. DFG method S19 is also included in the respective European Standards. Subsequently, a modification of the extraction and partition step has been implemented. The modified method requires less experimental effort and eliminates the use of dichloromethane, which is an undesirable solvent for toxicological and ecological reasons. As the results from validation studies demonstrate,... 

With a portion of the sample, determine the water content in grams per 100 g. As an alternative, take the approximate water content from Table A1 in the Appendix of DFG method S19 or from another literature source. 

Figure 2 Azole mixture B analyzed with multi-residue method DFG S19 on an HP 35MS instrument (chlorpyriphos-ethyl as...

G. Kempe, E.-M. Kschonek, and K. Speer, Assessment of the DFG Method S 19-Online for Residue Analysis of Azole Pesticides, Presented at the 3rd European Pesticide Residue Workshop, York, UK, July 3-5, 2000. 

DFG method S19 (extended revision) multi-method L 00.00-34 of the Official Collection of Test Methods According to 35 LMBG has been validated for azoxystrobin in orange, garlic, kohlrabi, camomile, fennel seed and tea. Extraction module El, cleanup module GPC and detection module D4 (MSD) were used for orange, kohlrabi and garlic. Extraction module E2, cleanup modules GPC and Cl and detection module D4 (MSD) were used for camomile, fennel seed and tea. 

Fenpyroximate and M-1 residues in the plant (apple, grape, etc.) and soil samples can be analyzed using the multi-residue method Method DFG 819 with some minor deviations. In this method, gel permeation chromatography (GPC) is effectively used as the cleanup procedure. Residues in the water sample can be analyzed by a simpler method. 

W. Specht, Organochlorine, organophosphorus, nitrogen-containing and other pesticides, S 19, in Manual of Pesticide Residue Analysis (DFG, Deutsche Forschungsgemeinschaft, Pesticides Comm.), ed. H.-P. Their and H. Zeumer, VCH, Weinheim, Vol. 1, pp. 383-400 (1987). 

The hyperpolarizability tensor is obtained in a way similar to the case of SHG. However, the selection rules for an SFG resonance at the IR frequency implies that the vibrational mode is both IR and Raman active, as the SF hyperpolarizability tensor elements involve both an IR absorption and a Raman-anti-Stokes cross-section. Conversely, the DFG hyperpolarizability tensor elements involve an IR absorption and a Raman-Stokes cross-section. The hyperpolarizability tensor elements can be written in a rather compact form involving several vibrational excitations as [117] ... 

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