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Versuche zur Hitzeresistenz-Adaptation bei höheren Pflanzen   总被引:1,自引:0,他引:1  
  相似文献   
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We analyzed 13 years of hourly measurements of SO2, NOx, and O3, at forest ecosystem research sites in SE Germany. A quasi-continuous data record was obtained by combining data sets from two locations. Before interpreting trends in the combined data set, we analyzed if the change of location introduced a systematic bias. We employed autocorrelation functions, Hurst statistics, complexity analysis, and recurrence quantification and found that the partial data sets exhibited no indication of the presence of any bias. For SO2, we also compared the data from the forest sites with data obtained in nearby cities and also found no indications for any systematic effects. Applying nonparametric trend statistics we found a significant decrease of the SO2. Most of the observed decrease is due to the reductions of SO2 emissions in eastern Germany, but reductions in western Germany and the Czech Republic also played important roles. For O3, we observed a significant increase, the causes of which are unclear from our data alone. No trend was identified for NOx.  相似文献   
98.
Die Kenntnis biochemischer Veränderungen von lipophilen körperfremden Stoffen ist hinsichtlich deren Elimination aus dem Organismus, sowie bei Überlegungen zur Voraussage toxischer, insbesondere carcinogener Wirkungen von vorrangiger Bedeutung  相似文献   
99.
The hypotheses on the de novo syntheses of polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo‐p‐dioxins (PCDDs), based on known literature, are presented. Polychlorinated benzenes and polychlorinated phenols are probably key intermediates.

In the present article, hypotheses that may account for the presence of polychlorinated dibenzofurans (PCDFs) and dibenzo‐p‐dioxins (PCDDs) in the effluents from municipal and industrial incinerators are put forward. These hypotheses are based on the previously surveyed literature (Ref. 203–206) and experimental results on laboratory scale and thermodynamic calculations are considered. The interconnections of various reaction steps are speculative and no technological information was added to account for conditions in real incinerators. Conclusion of the discussions on the related subject matter, presented in the Parts I‐IV (Ref. 203–206), are also described in this paper.  相似文献   
100.
SUMMARY

Regional business concepts are said to have huge potential to support sustainable development in industrialised countries (e.g. Stransfeld, 1999). However, whereas efforts have been made to implement regional concepts within agriculture and forestry, empirical findings show that regional concepts are only of minor importance to managers within industrial production (Rentz et al., 2000). Considering this situation, the aim of the present article is to explain why regional business concepts have rarely been implemented in the field of industrial production. Therefore, in the course of the present article, a raster for the identification of relevant barriers on a personal, enterprise, inter-firm and macroeconomic level will be developed and applied. Subsequently, suggestions for a set of measures to overcome these barriers to regionalisation will be given. The results have been identified in the framework of a questionnaire to about 30 decision makers of industrial companies within research, a project promoted by the German Ministry of Education and Research.  相似文献   
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