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Bürgerschaftliches Engagement - Konjunktur und Ambivalnez einer gesellschaftspolitischen Debatte
(2001)
Die Stellung der Landwirtschaft im Naturschutzrecht besitzt für das Verhältnis von Naturschutz und Landwirtschaft eine zentrale Bedeutung. Obwohl von der Landwirtschaft als dem größten Flächennutzer erhebliche Umweltbelastungen ausgehen, ist sie durch eine Vielzahl von Ausnahmeregelungen von zentralen Instrumenten des Naturschutzes wie der Eingriffsregelung ausgenommen und gegenüber anderen Nutzungen privilegiert. Hinzu kommen unterschiedliche Anforderungen in den Ländern. Bei der Weiterentwicklung des Naturschutzrechts stehen die Anforderungen des Naturschutzes an die Landwirtschaft regelmäßig im Mittelpunkt der politischen Auseinandersetzung. Vor dem Hintergrund der aktuellen Krise in der Landwirtschaft wird das rechtliche Verhältnis von Landwirtschaft und Naturschutz analysiert und Möglichkeiten für eine Weiterentwicklung aufgezeigt.
50 Jahre Europarat
(2001)
Organic Farming as a Compensatory Measure German's agricultural land is not only being gobbled up by development; whole sections are being bought up in compensation for interventions made elsewhere, thus rapidly decimating the countrie's farming land resources. For this reason, calls are being made to take land that is converted from conventional to organic farming and add it to the pool of "compensation" areas, thus killing two birds - one of them being the establishment of more organic farming - with one stone. Various German regions have adopted the approach. Although organic farming serves both agricultural and environmental objectives, it cannot cover all the requirements of nature conservation. For example, it benefits abiotic resources such as soil and water through its use of natural fertilizers and erosion-combating cultivation, but can do little to protect highly endangered species and biotopes. Moreover, organic farms do not necessarily meet the legal requirement that compensation land must fulfil a similar function to the land it is "compensating" for. In other words, land converted to organic farming cannot necessarily ameliorate or compensate for impact on biotopes and species elsewhere. Regarding this approach as a solution to the rapid disappearance of farming land simply diverts attnetion away from the real cause: Urban sprawl and road building.
Belegschaftsrechte ernstgenommen : Status quo und Perspektive der Demokratisierung am Arbeitsplatz
(2001)
In der Rezension wird darauf verwiesen, wie mit EDV-gestützten Methoden Quellengruppen besser erschlossen und neue Erkenntnisse gewonnen werden können. Herr Kamke, der Autor des zu rezensierenden Buches, stellt wichtige Einsichten zur Entstehung und Entwicklung agrarischer Strukturen zwischen Havel und Oder zur Diskussion, auf deren Grundlage eine systematische Analyse fortgesetzt werden kann.
Die Permanenz der Revolution
(2001)
Selbstgesteuertes Lernen
(2001)
Ausweichklauseln im deutschen, österreichischen und schweizerischen Internationalen Privatrecht
(2001)
Zwischen Arbeitsmarkt und Sozialintegration : zur Bedeutung des Zweiten Arbeitsmarks im Sport
(2001)
Grundlagen digitaler Systeme
(2001)
Especially sulphur containing compounds are suitable for the separation of noble metals[ , ]. 1,2-Dithioethenes are weak chelate-forming ligands [ ]and in the case of bis(methylthio)maleonitrile[ ] the donor power of both of the sulphur atoms is further decreased by the electron withdrawing effect of the cyanogroups. Crowned dithiomaleonitrile are macrocyclic chelate ligands which extract Pd(II) at sufficient rate in a very good yields. The reason for that extraction behaviour is the fact that Pd(II) favours the square planar coordination geometry in opposite to the 3d- elements. The synthesis of the immobilized ligands proceeds from the 2-allyloxy-1,2-propanediol forming the dicarbon acid which is reduced to the diole. With the help of thionylchloride the dichloro compound is synthesized forming together with a dithiolate (1,2-disodium-1,2-dicyanethene-1,2-dithiolate, 1,2-disodium-4-methylbenzene-1,2-dithiolate [ ]) at high dilution conditions the macrocycle. Than the allysubstituted crown ether is sillylated and the resulting alkoxysilane is immobilised onto activated silca gel. The substituent forms in the same time a spacer should be modified in the future. By immobilisation at an inactive matrix the selectivity of the ligand should be applied for the accumulation of palladium from diluted solutions. The extraction was performed from nitric acid solution with a yield of 93% into a ligand solution (chloroform, kerosine). The extraction equilibrium is reached after 10 min. By atomic absorption spectroscopy the metal concentration in the aqueous phase was determined to calculate the extraction rate. By modification of the cavity of the macrocyclus the extraction rate increases from the acyclic compound through maleonitrile-dithio-21-crown-7, maleonitrile-dithio-15-crown-5 and maleonitrile-18-crown-6. The best results can be observed at the maleonitrile-dithio-12-crown-4. The rise of the function lg D= f(lg L) gives the composition of the extracted compounds as 1:1. The separation is unsatisfactory in the case of Ag(I), Hg(II), Pt(II), Tl (I) and the most 3d-elements. Also Ni(II) as a representative for the 3d-elements shows only separations coefficients of 1.43?103 . Summarizing, a very good separation of palladium from the examined elements can be specified. Additional to the extraction experiments, as well as the crystal structures and by UV spectroscopy the formation constants of selected chelates were determined. The observed order corresponds to that found by the extraction of palladium in the system water/chloroform. In the case of maleonitrile-dithio-15-crown-5 Ag(I) is endocyclic coordinated with all donor atoms of the macrocyclus. Already maleonitrile-dithio-18-crown-6 can include the silver cation into its greater cavity. In these cases a 1:1 complex is formed. A 1:2 sandwich structure was noticed only in the case of the smaller ligand maleonitrile- dithio-12-crown-4. Obviously, the formation of that structure is not favoured in the system water/chloroform from which can be explained the unfavourable extraction results.
Untersuchungen zur Wirksamkeit der naturschutzrechtlichen Eingriffsregelung im Nordraum Leipzig
(2001)
Was ist politisches Handeln?
(2001)
Der Aufsatz stellt die geschichtliche Entwicklung der Menschenrechtsidee überblickartig dar, beschreibt Stationen ihrer Verwirklung und erläutert den gegenwärtigen völkerrechtlichen Menschenrechtsschutz. Die normativen Grundlagen und Möglichkeiten der Überwachung der so gesetzten Standards werden beschrieben. Abschließend nimmt der Aufsatz aktuelle Herausforderungen an den Menschenrechtsschutz zu Beginn des neuen Jahrtausends in den Blick. Es handelt sich um die gekürzte Fassung eines Beitrages, der im Sommer 2001 in einem Sammelband veröffentlicht wird.
100 [Einhundert] Jahre BGB
(2001)
Based on a study of the German Ministry of Research and Technology in 1990 every year about 2.5 t of heavy metals are released per hectare of landfill by aqueous leaching. This leachate contains approximately 2000 t of heavy metals per year. Their decontaminations in accordance with the legal requirements represent an enormous potential for easing the burden on the environment. On the other hand, this potential opens new possibilities in the production and recycling of selected compounds. The composition of a given model solution corresponds to a landfill leachate resulting from a municipal dump leachate produced by an average German city. Actually, in most cases, a decontamination of such solutions occurs by the transfer of the problematic cations into insoluble compounds usually done by precipitation. The result of the procedure is an unspecific separation of all liquid components - and the "cycle of waste" (landfill- leaching-deposition) begins anew, certainly on a higher level. The objective of our work is the simultaneous separation of heavy metals from alkaline earth metals and iron in order to obtain a leachate which we can lead back to the landfill. The reactive extraction as a separation process offers the possibility of a selective separation of cations that is the separation of toxic - from unproblematic components and includes also the possibility of electrolysis or further winning processes to obtain the wished metals. For the realisation of extraction processes, several commercial extractants and technical equipments are available. Apart from iron, LIX 54 could be used advantageously for an extraction process - unfortunately without any considerable extraction of cadmium. But it is favourable to separate non toxic alkaline earth metals from problematic heavy metals. Such a complex task as the separation of cations from natural solutions cannot be solved easily in a one-step-extraction process. Better results should be obtained by the combination of different procedures, e.g. extraction, ion-exchange and precipitation.
Wo Wasser Weiden wachsen läßt : Witterungsbedingte Dynamik von Geosystemen der mongolischen Steppe
(2001)
Ausgleich nur auf dem Papier
(2001)