WorldWideScience
 
 
1

The Nature of Arsenic-Phytochelatin Complexes in Holcus lanatus and Pteris cretica1  

UK PubMed Central (United Kingdom)

We have developed a method to extract and separate phytochelatins (PCs)—metal(loid) complexes using parallel metal(loid)-specific (inductively coupled plasma-mass spectrometry) and organic-specific...Full Text Available

2004-03-01

2

Stochastic aspects of dam safety analysis  

Energy Technology Data Exchange (ETDEWEB)

A stochastic analysis is presented of the probability of overtopping of a dam. The discussion is based on the case of a dam for a small water storage reservoir which has recently been constructed in the Saar district in the FRG. The problem is first solved by means of a simulation method. However, it is possible to describe the result of the sumulation method by means of a much simpler model which is based on a solution of the failure integral of Freudenthal for uncorrelated resistances and loads. It is shown that the actual safety of this dam against overtopping is extremely sensitive to both the operation rule for the reservoir, and the freeboard allowance. Some general conclusions are derived from this study for assisting in the ongoing discussion of dam safety. (6 figs, 1 tab, 7 refs)

1988-05-15

3

Long-distance transport, vacuolar sequestration, tolerance, and transcriptional responses induced by cadmium and arsenic  

British Library Electronic Table of Contents (United Kingdom)

Iron, zinc, copper and manganese are essential metals for cellular enzyme functions while cadmium, mercury and the metalloid arsenic lack any biological function. Both, essential metals, at high concentrations, and non-essential metals and metalloids are extremely reactive and toxic. Therefore, plants have acquired specialized mechanisms to sense, transport and maintain essential metals within physiological concentrations and to detoxify non-essential metals and metalloids. This review focuses on the recent identification of transporters that sequester cadmium and arsenic in vacuoles and the mechanisms mediating the partitioning of these metal(loid)s between roots and shoots. We further discuss recent models of phloem-mediated long-distance transport, seed accumulation of Cd and As and rec...

2011-01-01

4

Flue Gas Cleanup at Temperatures about 1400 C for a Coal Fired Combined Cycle Power Plant: State and Perspectives in the Pressurized Pulverized Coal Combustion (PPCC) Project  

Energy Technology Data Exchange (ETDEWEB)

The PPCC technology, a combined cycle, requires comprehensive cleaning of the flue gases because coal contains a large variety of minerals and other substances. This would lead to fast destruction of the gas turbine blades due to erosion and corrosion. The present specifications of the turbine manufacturers for the required flue gas quality are at a maximum particulate content of 5 mg/m3 s.t.p., diameter of < 5 {micro}m, and a maximum alkali content < 0.01 mg/m3 s.t.p. The PPCC project is aimed at cleaning the flue gases of pressurized coal combustion. This method will be applied at temperature ranges where the ash is in a liquid state and which will be thus cleaned from coarse particulate material by agglomeration and inertial force separators. Appropriate separating methods are also being investigated and developed for the hazardous gaseous contents, e.g. alkali compounds, which are released during the coal combustion process. The following companies are working on the ...

2002-09-18