Was ist das Baugrundrisiko? Replik zu <Emphasis Type="Italic">Wenusch,</Emphasis> „<Emphasis Type="Italic">Nochmals:</Emphasis><Emphasis Type="Italic">Das Baugrundrisiko</Emphasis>“, bbl 2011, 109

Wer das Baugrundrisiko tr?gt, wird von § 1168a ABGB eindeutig zugeordnet: Das Baugrundrisiko tr?gt der, der den Baugrund ausw?hlt und beistellt, also der, aus dessen „Sph?re“ der Baugrund stammt. Wenusch hat in seinem Artikel diesen Grundsatz hinterfragt, hat aber überlegungen zur Bedeutung bzw. den Auswirkungen einer funktionalen Leistungsbeschreibung überschie?end auf diese gesetzliche Risikozuordnung übertragen. Auf Grund der gro?en Bedeutung dieser Thematik für die betroffenen Verkehrskreise ist eine Replik angezeigt.     

The effect of carbon dioxide on the viability of bacteria of <Emphasis Type="Italic">Bacillus</Emphasis> and <Emphasis Type="Italic">Diplococcus</Emphasis> genera

The effect of the volume of carbon dioxide gas released from aqueous solution on the reduction of the number of vegetative microorganisms per unit volume of the system has been investigated. A linear relationship between the number of vegetative microorganisms and the volume of released carbon dioxide is observed, when the volume of the released gas does not exceed the level of 0.5 dm³/dm³ of solution. The increasing ratio of the amount of spores to the number of vegetative bacteria of Bacillus genus results in a largely reduced impact of the volume of released carbon dioxide on the microbial viability.     

A method for mapping the spatial distribution of <Emphasis Type="Italic">RockFall</Emphasis> computer program analyses results using <Emphasis Type="Italic">ArcGIS</Emphasis> software

Rockfalls are a natural process of cliff and hillside erosion and can be simulated by computer programs. RocFall is a useful and well-known program which produces envelopes of kinetic energy, velocity, bounce height and fall-out distance for a selected profile. However, with this program it is difficult to record the spatial distribution of the envelopes in their exact coordinates in GIS. In this paper, a method and computer code (FallGIS) written by the authors is proposed for mapping the results obtained from RocFall in ArcGIS. As it is both user-friendly (hence quicker) and does not require any new software, it is hoped it will be a useful tool for engineering geologists, urban planners, etc.      

An analysis of economic cost minimization and biological invasion damage control using the <Emphasis Type="Italic">AWQ</Emphasis> criterion

DeAngelo et al. (New approaches to the Economics of plant health. Springer, Heidelberg, 2006) have recently used the AWS criterion in a M/G/1 queuing model to show that there is no necessary tension between economic cost minimization and inspection stringency in non-native species management. In this paper, we use an alternate cost criterion (AWQ criterion) to investigate the generality of this central result in DeAngelo et al. (New approaches to the Economics of plant health. Springer, Heidelberg, 2006). Our theoretical analysis shows that there is no unambiguous answer to this question. Therefore, we use numerical methods and our numerical analysis leads to two findings. First, for many values of the model parameters that describe the strictness of inspections, there is a tension between cost minimization and inspection stringency. Second, for most values of the model parameter that depicts the volume of maritime trade handled by the seaport under consideration, there is no tension between cost minimization and inspection stringency.      

The method of eliminating phenol with the use of tyrosinase <Emphasis Type="Italic">Agaricus bisporus</Emphasis> immobilized in alginate

We have considered the method of oxidizing aqueous solutions of phenol (0.25–2.00 mmol/dm³) with the use of a biocatalyst—a partially purified tyrosinase immobilized into calcium alginate. In optimal conditions (pH 7.2, T—25°C, transformation time—one hour, phenoloxidase activity—25–200 unit/cm³) when adding a PEG-6000 stabilizer the preparation stabilized complete oxidation of phenol in a periodic-action reactor during 12 cycles and retained a high degree of transformation of the substrate during the following 16 cycles. The concentrations of coagulants necessary for elimination of transformation products using the immobilized enzyme were reduced 2.5-fold compared with such for a free biocatalyst.     

The impact of the wastewater composition on the rate of chlorate reduction by the culture <Emphasis Type="Italic">Acinetobacter thermotoleranticus</Emphasis> C-1

The paper has proposed a mathematical model adequately describing the process of reducing chlorates by the culture Acinetobacter thermotoleranticus C-1 in the presence in the medium of the components incorporated into the wastewater composition of the ignition compound industry. It is shown that an adverse impact on the rate of chlorate utilization is produced by zinc and chromates. Phosphates slow down chlorate reduction a little. The presence of trivalent iron stimulates microbial reduction of chlorates.     

Inactivation of the test microorganism <Emphasis Type="Italic">E.coli K-12</Emphasis> with ozone in water in the presence of humic acids and hydrogen peroxide

It was found that in the water containing impurities in the presence of ozone radical reactions occur. In this case stable activated oxygen-containing radicals as well as radicals of organic compounds are formed. The radicals play a significant role in the processes of water decontamination with ozone.     

Sorption of ions of U(VI) and strontium by biosorption based on <Emphasis Type="Italic">Bacillus polymyxa</Emphasis> IMV 8910 in aqueous systems

We have investigated the influence of individual components of waters (humic acids, anions, and cations) on sorption of ions of U(VI) and strontium by the biosorbent based on the Bacillus polymyxa IMV 8919 cells. It is shown that during transition to real aqueous systems there occurs a decrease of the degree of extracting U(VI) and strontium by a microbial sorbent. Extraction of strontium in a great degree depends on the concentration in water of bivalent cations, which may compete with it in the sorption processes. A degree of purification of U(VI) is mainly determined by the pH of the medium. Acidification of aqueous media containing uranium, up to pH 5 makes it possible to raise the degree of extraction of metals by means of a biosorbent     

Heterogeneous rock mass classification by means of the geological strength index: the <Emphasis Type="Italic">San Mauro</Emphasis> formation (Cilento,Italy)

This paper describes an application of the geological strength index (GSI) method to the San Mauro formation, which is characterized by sandstones alternating with argillaceous marls. The Sandstone/Pelite (S/P) ratio and structural complexity were determined. Geo-structural and geo-mechanical surveys were undertaken in situ and rock samples were tested in the laboratory. A map of the S/P ratio was produced showing the bedrock divided in four classes. Three ranges of GSI values were identified. The values of the intact UCS and of the constant m _i were appropriately reduced to reflect the variable presence of sandstone compared with the pelitic fraction. A “weighted average” of the intact strength properties of the hard and weak layers was adopted. The values for the intact materials were reduced from 20 to 60% depending on the GSI categories of the heterogeneous rock mass. In this way, seven classes of rock masses characterized by different values of GSI, reduced UCS and m _i values were identified.     

The change of the electrokinetic potential of <Emphasis Type="Italic">Bacillus polymyxa</Emphasis> IMV 8910 cells in interaction with ions of U(VI) and strontium

We investigated the change of the electrokinetic properties of B. polymyxa IMV 8910 cells in interaction with the ions of U(VI) and strontium. It was found that initial live and thermally inactivated cells are characterized by close values of the ζ-potential: respectively 30 and 28 mV. It is shown that increasing concentrations of metals in a different way affect the value of the ζ-potential of live and thermoinactivated cells B. polymyxa IMV 8910. We have found the relationship between the ζ-potential of the cells’ data and, accordingly, the adsorption value of ions of U(VI) and strontium and the pH of the medium.     

Inactivation of <Emphasis Type="Italic">Candida albicans</Emphasis> in the photo-fenton system

The paper has investigated photocatalytic decontamination of the culture of micromycetes Candida albicans in water media depending on the radiation dose (UV-A range), the pH of the medium, the concentration of H₂O₂, ions of iron (II), (III), and phosphate ions. We proposed the interpretation of the impact of the specified factors on the rate of the course of the process being investigated. We showed prospects of using the UV/H₂O₂ and photo-Fenton systems as applied to decontamination of water media from micromycetes Candida albicans.     

Formation of viable noncultural state of <Emphasis Type="Italic">Candida Albicans</Emphasis>

The paper has investigated the influence of NaOCl on the cells of Candida albicas with the aim of finding viable noncultural state and also conditions of their rehabilitation. Microscopic research of the cells Candida albicans has been given in the indicated state colored with trypan blue.     

Fuel Moisture Thresholds in the Flammability of <Emphasis Type="Italic">Calluna vulgaris</Emphasis>

Managed and wild fires play a significant role in the ecology of heathlands in the UK but we currently have little ability to forecast fire behaviour or the likelihood of accidental wildfires. Like many shrubland fuel types, heathlands display significant structural complexity and the role of different fuel components in governing flammability has not been clear. Using a series of small, field-based ignition tests, we demonstrate the critical importance of the moisture content of dead fine fuels in the lower canopy for determining when sustaining fires in the vegetation canopy can develop. At moisture contents above c. 70% both spot and line ignitions failed but where moisture contents were less than c. 60% fires developed rapidly. The initial rate of spread of successful ignitions was primarily controlled by the moisture content of the lower canopy and the moss/litter layer. Models that predict the moisture content of elevated dead fuels and the moss litter layer are urgently needed in order to protect heathlands from wildfire and to allow forecasts of the suitability of conditions for prescribed burning to be developed.     

An Evaluation of <Emphasis Type="Italic">Old</Emphasis> Armored Cables in Building Wiring Systems

Armored cable has been used in building wiring systems since the early 1900s and remains an accepted wiring method today. The original product developed in the early 1900s and that which is commercially available today have significant differences in construction and performance. Likewise the demand and expectation of building wiring systems has changed. This paper explores some of those differences as well as concerns and hazards presented by the continued use of older constructions of armored cable. Testing was performed on samples of aged cables removed from service to determine impedance and temperature rise of the armor when conducting AC current. The results were compared to the DC resistance of the armor as well as the applicable Underwriters Laboratories standard. The performance of cable samples was also tested in construction configurations likely to be encountered in buildings. Results indicate that ground fault currents conducted via the armor of older cable constructions can result in fire and shock hazards where the impedance and circuit characteristics limit the fault current to below the trip level of the circuit overcurrent protective device. Temperature rise of the armor can easily exceed the rating of the conductor insulation contained therein and in some cases present a fire hazard to combustible material in contact with the cable.     

Optimal recultivation conditions of <Emphasis Type="Italic">Candida Albicans</Emphasis> staying in non-culturable state

Optimal conditions for recultivation of Candida albicans staying in viable but non-culturable state have been established. The effect of sodium hypochlorite on the transition of this culture into non-culturable state was investigated. The conditions of the culture reactivation were determined. These conditions include the effect of M-9 nutrient medium components and the cultivation temperature on recultivation process.