Über die Eignung von thermo-mechanischem und chemo-thermo-mechanischem Holzstoff (TMP und CTMP) aus Buchen- und Kiefernholz für die Herstellung von mitteldichten Faserplatten (MDF)

Medium density fibreboards (MDF) were made from beech in laboratory and pilot plant scale from thermo-mechanical (TMP) and chemo-thermo-mechanical pulps (CTMP) using both melamine reinforced urea-formaldehyde resin (UF-resin) and diphenylmethane diisocyanate polymers (PMDI). The physicalmechanical and chemical properties of the boards were evaluated. From the results the following conclusions can be drawn:

1. Both TMP and CTMP led, on using UF-resin, to MDF with very high mechanical properties exceeding the required values in European standards.
2. Pulping temperature seems to have an influence on the mechanical properties of the boards, prepared from TMP and CTMP. Increasing the pulping temperature from 150°C to 170°C negatively affects the mechanical board properties, whereas the properties of MDF from CTMP (sulfonic group content between 0.2% and 0.3%) increases by elevating the maximum pulping temperature from 150°C to 170°C.
3. The pulping chemicals in the CTMP-process (Na₂SO₃ and/or NaOH) decrease the formaldehyde release from the boards, as they act as scavengers for formaldehyde.
4. Due to higher deacetylation degree during CTMP process, MDF made from CTMP release more than 4 times acetic acid than MDF from TMP. The release of formic acid is quite different, it is in MDF, made from TMP higher than in MDF from CTMP.
5. MDF with very high mechanical properties can also be made from beech pulps (TMP) using PMDI. PMDI in combination with a formaldehyde scavenger in the middle layer and UF-resin in the surface layer leads to boards with very low formaldehyde release.

     

Toxikologie der Perfluoroctansäure (PFOA) und der Perfluoroctansulfonsäure (PFOS)

Zusammenfassung:  Perfluorierte Tenside (PFT) werden seit einigen Jahren weltweit in der Umwelt, in menschlichen Blut- und Muttermilchproben sowie in Lebensmitteln nachgewiesen. In den letzten Jahren wurden auf nationaler und internationaler Ebene - zum überwiegenden Teil vorl?ufige - Risikobewertungen für die perfluorierten Tenside Perfluoroctans?ure (PFOA) und Perfluoroctansulfons?ure (PFOS) erarbeitet. Diese beiden Verbindungen werden als Leitsubstanzen für die Substanzklasse angesehen. Aus Sicht der humantoxikologischen Bewertung sind die lange Persistenz im menschlichen Organismus und die F?higkeit, im Tierversuch verschiedene adverse Effekte auszul?sen, als kritische Eigenschaften dieser Verbindungen anzusehen. Um den vielen Aspekten der Toxikologie von PFOS und PFOA gerecht zu werden, die im Rahmen dieser Darstellung nicht beleuchtet werden k?nnen, sei für weitere Informationen auf ausführliche übersichtsartikel verwiesen (Andersen et al., 2008; Lau et al., 2007). Eingegangen: 28. April 2008; angenommen: 8. Mai 2008     

Alkaloid- (und purink?rper-)haltige Genu?mittel

Ohne ZusammenfassungEinschließlich Referate von Arbeiten in Fortschrittsberichten u. dgl.     

Alkaloid- (und purink?rper-)haltige genu?mittel

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Alkaloid- (und purink?rper-) haltife Fenu?mittel

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Alkaloid- (und purink?per-)haltige Genu?mottel

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Alkaloid- (und purink?rper-) haltige genu?mittel

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Standpunkte, Praktiken und Kenntnisstand zur Ferkelkastration in Europa (PIGCAS) – Projektziele und erste Ergebnisse

Most of the male piglets in the EU are castrated. According to the current EU legislation, surgical castration can be performed without anaesthesia up to the age of 7 days. A report of the European Food Safety Authority (EFSA) on the welfare aspects in relation to the castration of pigs has underlined the need for further research. As a follow up, the EU has launched a two-year project (Specific Support Action PIGCAS) within the 6^th EU Framework Programme, starting in January 2007. “PIGCAS” is the acronym for “Attitudes, practices and state of the art regarding piglet castration in Europe”. The main objectives are: [A] to collect information on the attitudes of the various stakeholders (consumer groups, NGOs and industry stakeholders); [B] to collect information on the extent of the practice of castration of piglets (male or female) within the EU and the conditions under which castration is performed; [C] to evaluate research work and other sources of information, in order to examine surgical castration without anaesthesia and its possible alternatives from different perspectives and derive research priorities; and [D] to integrate the collected information and evaluation in a report providing support for EU policy in the field of research and legislation. Preliminary results are now available on objectives [A] and [B]. When referring to the alternatives to surgical castration, one has to distinguish between short-term and long-term solutions. Surgical castration with anaesthesia was mentioned by most of the stakeholders as a short-term alternative. Genetic control of boar taint and sperm sexing to select only females for pork production are considered as long-term alternatives. Current practices of castration and levels of acceptability vary substantially between and within countries and regions. The current research focuses on practical methods for acute and postoperative pain alleviation and analyses the complex consequences of raising entire males or immunocastrated boars. Considering the different dimensions (attitudes, extent of practice, animal welfare, pork quality and economy) of importance, it is intended to propose to the EU short and long-term strategies to handle this problem.

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Eingegangen: 26. Februar 2008; angenommen: 29. Februar 2008     

Alkaloid- (und purink?rper-)haltige Genu?mittel

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Alkaloid- (und purink?rper-)haltige Genu?mittel

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