Geoscientific maps as an aid to land use and regional planning

Successful regional and land use planning today requires an optimal use of available natural resources. Geoscientific maps of the natural environment's potential satisfy the geoscientific part of this requirement. These maps are presented for politicians, laymen and planners in easily understood form as simple thematic maps (for soil, groundwater, mineral deposits, geological engineering, proposals for priority utilization from the geoscientific point of view and other geological facts important to society). In this way optimal use of the geogenic potential at specific places is made possible.     

The lower explosion point—A good measure for explosion prevention: Experiment and calculation for pure compounds and some mixtures

It is well known that explosive mixtures can exist at temperatures below the flash point (FP). Experiments show that the difference between the FP and the lower explosion point (LEP) may be up to 15 K and in some special cases even more. Consequently, an industrial process even running a few Kelvin below the FP may operate in an explosive vapour/air-atmosphere. Operating at temperatures below the LEP gives sufficient safety. Calculated LEPs are discussed and compared with experimental results.     

Purification of Aspergillus fumigatus (Pdf1) Poly(β-hydroxybutyrate) (PHB) Depolymerase Using a New, Single-Step Substrate Affinity Chromatography Method: Characterization of the PHB Depolymerase Exhibiting Novel Self-Aggregation Behavior

The extracellular poly(-hydroxybutyrate) (PHB) depolymerase of Aspergillus fumigatus Pdf1 was purified by a new, simple, one-step affinity chromatography method using the substrate PHB. The purified enzyme was glycosylated, with the molecular mass of 40 KD, and exhibited a novel self-aggregation behavior by means of hydrophobic interaction that was resolved by Triton X-100 (TX-100) pretreatment of enzyme and also TX-100 incorporation in the native gel. The apparent K _m value of purified enzyme for PHB was 119 g/mL and 3-hydroxybutyrate was detected as the main endproduct of PHB hydrolysis. The depolymerase was insensitive to phenylmethyl sulfonyl fluoride (PMSF), sodium azide, ethylenediaminetetraacetic acid (EDTA), and para-chloromercuric benzoic acid (PCMB), but was inactivated by dithioerythritol (DTT) and showed specificity for short chain-length poly(-hydroxyalkanoates) (PHAs) such as PHB, poly(hydroxyvalerate) (PHV), and copolymers of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV). Medium-chain-length PHA failed to get hydrolyzed. The enzyme, however, exhibited strong cross reactivity with the Comamonas sp. PHB depolymerase antibodies, but not with PHV depolymerase antibodies of Pseudomonas lemoignei. Southern hybridization and dot blot analysis of A. fumigatus Pdf1 genomic DNA with alkaline phosphatase labeled probes of P. lemoignei PHB and PHV depolymerase genes revealed no homology, although the enzyme hydrolyzed both PHB and PHV.     

Einsatz eines Sensors zurOnline-Bestimmung der mikrobiellen Aktivit?t

Zusammenfassung  Mit einem Bioaktivit?tssensor kann die Aktivit?t der Mikroorganismen im Belebtschlamm gemessen werden. Das Signal des Sensors reagiert empfindlich auf eine Ver?nderung des Substratangebots und das Auftreten von toxischen Stoffen. Mit dem Bioaktivit?tssensor ist es damit einerseits m?glich,online die Belebungsstufe hinsichtlich ihrer mikrobiellen Aktivit?t zu kontrollieren und andererseits die zuflie?enden Abw?sser bezüglich ihres toxischen Potentials zu überwachen.      

A prospective cytogenetic study of third-trimester placentae in small-for-date but otherwise normal newborns

Data in the literature suggest that confined placental mosaicism might be associated with intrauterine growth retardation. However, this association may be coincidental and due to bias of ascertainment. We therefore started a prospective study based on the cytogenetic evaluation of placentae derived from growth-retarded newborns. We further minimized possible bias by excluding those small-for-date infants displaying findings which already could explain intrauterine growth retardation (mothers who are smokers, multiple pregnancies, gestosis, dysmorphic infants). In a collection of 71 small-for-gestational age newborns, we did not see a single case of true confined placental mosaicism.     

Biodegradation behavior and material properties of aliphatic/aromatic polyesters of commercial importance

Copolyesters of aliphatic monomers with a defined amount of terephthalic acid recently have been shown to be biodegradable. This group of plastic materials exhibits very interesting material properties with regard to their technical application potential. A tensile strength of 25 N/mm² combined with elongations at break up to 1500% was achieved for BTA materials. Melting points varied from 80 to 140‡C. Biodegradation rate under compositing conditions were determined, showing typical erosion rates of films, in the range of 5 to 10 Μm/week. The material properties and the degradation rate as well can be adjusted by the copolymer composition. Stretching of the polymer in the cold state leads to 10-fold higher mechanical strength of the material. The polyester chain can be extended to high molar masses, resulting in melt viscosities suitable, e.g., for melt below extrusion.