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Supported Pd single atom catalysts (SACs) have triggered great research interest in methane combustion yet with contradicting views on their activity and stability. Here, we show that the Pd SAs can take different electronic structure and atomic geometry on ceria support, resulting in different catalytic properties. By a simple thermal pretreatment to ceria prior to Pd deposition, a unique anchoring site is created. The Pd SA, taking this site, can be activated to Pdδ+ (0δ2) that has greatly enhanced activity for methane oxidation: T50 lowered by up to 130 oC and almost 10 times higher turnover frequency compared to the untreated catalyst. The enhanced activity of Pdδ+ site is related to its oxygen-deficient local structure and elongated interacting distance with ceria, leading to enhanced capability in delivering reactive oxygen species and decomposing reaction intermediates. This work provides insights into designing highly efficient Pd SACs for oxidation reactions.

The growth of vertically aligned carbon nanofibers (VACNFs) in a catalytic dc ammonia/acetylene plasma process on silicon substrates is often accompanied by sidewall deposition of material that contains predominantly Si and N. In fluorescent microscopy experiments, whereby VACNFs are interfaced to cell and tissue cultures for a variety of applications, it was observed that this material is broadly fluorescent. In this paper, we provide insight into nature of these silicon/nitrogen in-situ coatings. We propose a potential mechanism for deposition of SiNx coating on the sidewalls of VACNFs during PECVD synthesis and explore the origin of the coating's fluorescence. It is most likely that the substrate reacts with process gases similar to reactive sputtering and chemical vapor deposition (CVD), forming silane and other silicon bearing compounds prior to isotropic deposition as a SiNx coating onto the VACNFs. The formation of Sinanoclusters (NCs) is also implicated due to a combination of strong fluorescence and elemental analysis of the samples. These broadly luminescent fibers can prove useful as registry markers in fluorescent cellular studies and for tagging and tracing applications.

The bat species Rhinolophus hipposideros has undergone a dramatic decline throughout much of western Europe from the 1960s. The mechanisms responsible for this phenomenon have not been conclusively identified. At the same time, some populations of Pipistrellus pipistrellus have increased substantially, possibly as a consequence of foraging upon insects attracted by street lamps. To evaluate whether there might be some ecological link between the opposite demographic trends observed in the two species, we compared the diets of two sympatric populations of R. hipposideros and P. pipistrellus in south-west Switzerland. The two bat species fed upon the same categories of prey, mainly moths and Diptera, and we were not able to recognize interspecific differences in diet composition in spring when resources were most likely to be limiting. Although using different foraging strategies, both species may visit the same or adjacent feeding grounds, therefore potentially competing for the same populations of prey. Although conclusive evidence is still needed, bat conservation policy should pay more attention to this possibility.

Verantwortung fur die Zukunft der Heranwachsenden und noch Ungeborenen ist das zentrale Kernthema der Nachhaltigkeit. Dies bedeutet, dass unser okologisches Kapital zulasten zukunftiger Generationen nicht aufgezehrt werden darf und verlangt ebenso den Erhalt des wirtschaftlichen und sozialen Kapitals. Diese Aufgabe ist eine der grosten Herausforderungen der Zukunft. Die Staatsregierung ist sich bewusst, dass dies nur durch das partnerschaftliche Zusammenspiel von gesellschaftlichen und staatlichen Kraften bewaltigt werden kann.

Public participation and transboundary issues play a vital role in the SEA procedure. In all EU Member States, including the ten accession states, the SEA Directive came into force in 2001. On the other hand, some EU Member States such as Germany have not fully adopted the Directive yet. Germany intends to amend the EIA Act by adding rules and SEA procedural steps such as public participation, transborder consultation, content of an environmental report and monitoring. Considering the federal structure of Germany all 16 federal states (Laender) will set up their own rules and regulations which will recognise specific requirements of the regions. Not only the EIA Act contains legal provisions on SEA but also other acts contain SEA rules (see Chap. 7). The most important provision of this kind is the Federal Spatial Planning Act, which rules the requirements of SEA on regional planning procedures. Despite the lack of practical experience with the SEA Directive some practical experience with national SEA-procedures could be obtained before the SEADirective was published. Experience with SEA before the EC Directive was published have been documented for example by Dusik at al. (2001) for Central and Eastern Europe, the Newly Independent States of the Former Soviet Union (NIS) by Cherp (2001), Norway by Swensen (2001), Czech by Vaclavikova and Jendrike (see Chap. 13), Poland by Mackowiak-Pandera and Jessel (see Chap. 14), Rzeszot (2001), Bulgaria by Grigorova and Metodieva (2001), and Slovenia by Kontic and Marega (2001).

Im Jahre 1995 wurde von der LABO-LAGAAG „Abfallverwertung auf devastierten Flachen“ im Auftrag der Umweltministerkonferenz (UMK) die Techni sche Richtlinie (TR) „Anforderungen an den Einsatz von Biokompost und Klarschlarnm bei der Rekultivierung von langjahrig devastierten Flachen in den neuen Bundeslandern“ erarbeitet. Die LABO/LAGA-TR soli fachlich auf Beschlus der UMK in den beteiligten Landern bis zum 31.12.1998 eingeftihrt werden. Mit dem Ablauf der Dreijahresfrist soll der UMK ein Verfahrensvorschlag gemacht und ein Erfahrungsbericht der Lander vorgelegt werden, in dem insbesondere zu prufen ist, ob die Bewertung der Schadstoffe hinsichtlich einer Verlagerung ins Grundwasser ausreichend ist. Mit einer moglichen Novellierung der Technischen Regeln (TR) ist nicht vor Ende 1999 zu rechnen. Der hier vorgelegte Leitfaden dient der praktischen Umsetzung dieser Richtlinie im Freistaat Sachsen. Er orientiert sich stark an der o. g. Regelung und ubernimmt gelegentlich Textteile ohne jegliche Anderung oder geringfugige Anpassung. Notwendige Anderungen bzw. Erganzungen wurden durchgefahrt. Die wesentlichen fachlichen Vorgaben wurden, soweit moglich, von dort ubernommen. Um die Nachvollziehbarkeit zu gewahrleisten, wurde das Inhaltsverzeichnis hier synchron zu dem der o. g. Technischen Richtlinie gestaltet. Im Leitfaden werden die detaillierten Berechnungsschritte, die notwendigen Angaben fur eine Anwendung sowie Anpassungsvorschlage aufgezeigt. Ein Programm soli die notwendigen Berechnungen erleichtern.

Stadtbaume sind einer Vielzahl von negativen Umwelteinflussen ausgesetzt. Zunehmende Umweltverschlechterung, insbesondere durch Verkehrsemissionen hervorgerufen, fuhrte in den letzten Jahrzehnten zu einem dramatischen Ansteigen der Baumschaden in den Stadten. Neben den als „Neuartige Waldschaden“ bekannten, durch Luftschadstoffe verursachten Immissionsschaden treten stadtspezifische, durch bauliche Masnahmen, intensive Nutzung, mangelnde Pflege oder ungeeignete Standorte hervorgerufene Schadeinflusse auf.

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This research was supported in part by the National Science Foundation and the Naval Postgraduate School Research Foundation

1. 1. “Unexpected post-partum hypertension,” coined term, is an idiopathic syndrome, relatively unstudied, and found by us only in the colored race. 2. 2. The findings in 51 cases are summarized in this report. 3. 3. Most of the patients are multiparas. 4. 4. Practically all of the patients were observed during the prenatal period for an adequate time period to allow for evaluation of the post-partum blood pressure. 5. 5. The duration of the post-partum rise is about six to seventeen weeks. It is self-limited. 6. 6. The maximum pressure while usually observed six weeks' post partum may be as late as 16 weeks post partum. 7. 7. The average normal colored patient shows a slightly higher post-partum pressure than does the average normal white patient. The average normal colored patient shows a lower prenatal pressure than does the colored patient who develops ”unexpected post-partum hypertension.” 8. 8. The syndrome may or may not be present at subsequent pregnancies and if so, may be more or less severe than the previous occurrence. 9. 9. No relationship of this syndrome to post-partum heart failure (idiopathic) has been apparent. 10. 10. No etiologic factor is evident; there is some suggestion that it is purely functional.

Modern high speed process lines demand good tension control for best performance. This paper deals specifically with the application of load cell type tensiometers on Stelco's no. 3 galvanizing line, however, the merits of this type of tension control apply as well to other process lines. It describes and shows the advantage of tension regulation by the use of tensiometers versus current regulation.

1. 1. Twenty-three cases, all colored patients, of postpartum hypertension following apparently normal pregnancy are described. 2. 2. The incidence was found to be 4.6 per cent of all the postpartum cases examined, both white and colored. 3. 3. Fifty-six per cent of the series were between twenty-one and thirty-one years of age. 4. 4. 82.6 per cent of the patients were multiparas. 5. 5. The average number of prenatal visits made was 9. 6. 6. Sixteen patients in the series had blood pressure readings lower than 130/90 during pregnancy. The remaining 7 cases are added due to the marked rise postpartum. An analysis of this latter group is given. 7. 7. All patients revealed increases in pressure at the routine six weeks postpartum examination. 8. 8. Only in 8 patients in the series was it definitely established that a normal blood pressure was eventually reached. 9. 9. The results of the laboratory work are shown. 10. 10. Postpartum medical consulation showed definite organic disease in 9 cases. 11. 11. There patients in this study have become pregnant again, and an analysis up until the present time is given

(e,e') from the giant dipole resonance (GDR) in /sup 140/Ce verifies the macroscopic model by Myers et al., while ruling out the Steinwedel-Jensen model and, to a lesser extent the Goldhaber-Teller model. This result leads to discrepancies between (..cap alpha..,..cap alpha..') and (e,e') concerning the existence of a giant-monopole (breathing-mode) state, particularly if one considers the independent verification of the Meyers et al. model by the experimental A/sup -0.23/ energy dependence of the GDR.

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