Environment specialised

Nickel-iron alloys have a number of important applications that are derived from such special physical properties as their unique magnetic characteristics in the regions of 35, 50 and 80% nickel and from their abnormally low thermal expansion in the region of 36-50% nickel. Although not specifically used as corrosion-resistant materials, their high resistance to attack from many common environments is of benefit in their specialised applications. 

Because of the many variables which can influence the corrosion reaction, the use of the e.m.f. series of metals to predict the behaviour of galvanic couples in a given service environment can be hazardous and misleading. Numerous examples of coatings expected to act cathodically which have, in fact, been anodic have been reported in the literature and specialised lists of galvanic couples in different environments have been compiled. ... 

Oilfields in the North Sea provide some of the harshest environments for polymers, coupled with a requirement for reliability. Many environmental tests have therefore been performed to demonstrate the fitness-for-purpose of the materials and the products before they are put into service. Of recent examples [33-35], a complete test rig has been set up to test 250-300 mm diameter pipes, made of steel with a polypropylene jacket for thermal insulation and corrosion protection, with a design temperature of 140 °C, internal pressures of up to 50 MPa (500 bar) and a water depth of 350 m (external pressure 3.5 MPa or 35 bar). In the test rig the oil filled pipes are maintained at 140 °C in constantly renewed sea water at a pressure of 30 bar. Tests last for 3 years and after 2 years there have been no significant changes in melt flow index or mechanical properties. A separate programme was established for the selection of materials for the internal sheath of pipelines, whose purpose is to contain the oil and protect the main steel armour windings. Environmental ageing was performed first (immersion in oil, sea water and acid) and followed by mechanical tests as well as specialised tests (rapid gas decompression, methane permeability) related to the application. Creep was measured separately. 

The following must be emphasised in particular involvement in the accompanying group of the Environment Ministry and participation in enquiries, conferences and specialised debates on the economic effects of the EU Commission s proposal for reform of European chemicals pohcy at the DG Enterprise on 21.5.02 subjects at the VCl events on 16.4.02 and 13.11.02 the UBA speciahsed debate on 6.2.03 and the BDl specialised debate on 20.2.03 as well as the European Environmental Bureau s (EEB) conferences in Copenhagen on 27/28.9.02 and in Brussels on 31.1/1.2.03. 

A market can only develop when the increased safety of chemical prodncts is recompensed by an actual willingness to pay. Private and professional chemical users only become concerned with the health and environment-related qnalities of a product (quality awareness) when they are informed effectively. Specialised journals and television news play an important role in this area. 

An entirely different, in fact opposite, effect on insect reproduction by terpenes occurs with the desert locust. In this case the monoterpenes a-pinene, -pinene, llmonene, and euge-nol evaporating from desert shrubs about to bloom, precipitates synchronised sexual maturation and mating activity in the locusts (14). The spruce budworm is also stimulated to increased fertility levels by host tree monoterpenes (R.G. Cates, personal communication). It is possible that even opposite effects on reproduction in insects could occur depending on the specialisation of the insect species to its environment, the diversity of the biological activities of the compounds, and the high level of complexity of the reproductive processes. 

Biologist and earth scientist. Researcher in plant physiology at the University of Vienna until 1991 (specialised in photosynthesis research, simulation of plant bio-productivity). Over 60 publications on environmental issues. 1992 invited speaker at the Alpbach Forum 1996 winner of the grand Austrian Environment Award (of Lower Austria) top-notch journalist on environmental issues admission to the "Austrian Scientific Forum for Environment Protection", board member since 2001. Director of the Chemicals Policy Division of the BMLFUW since the end of September 1997 fields of activity legislation on chemical substances at the national, European and UN levels. Scientific and technical risk assessment of substances and products, best practice diffusion for the production and application of chemical products. 

Gradually a tremendous arsenal of processes has been developed, allowing the analyst to respond to an increasing number of diverse demands. Furthermore, the study of modern chemical analysis techniques is far removed from traditional descriptive chemistry. Many analyses are conducted in non-specialised environments, either on site or at simple workbenches. The determination of compounds is currently quite remote from the use of chemical reactions, which are often avoided for many reasons. Former wet chemistry methods, at the origin of the term analytical chemistry, have become less important because they lack sensitivity, are lengthy and their precision can too easily be altered by the use of insufficiently pure reagents. Nonetheless, wet chemistry methods are still interesting to study. 

Much of the chemistry of the cell is common to all living systems and is directed towards ensuring growth and cell multiplication, or at least the survival of the cell. Organisms also share various structural characteristics. They all contain genetic material (DNA), membranes (the boundary material between the cell and the environment), cytoplasm (small particulate materials, ribosomes and enzyme complexes), and cell walls or surfaces (complex structures external to the membrane). In addition, there are various distinct membrane-bound organelles in eukaryotic organisms which have specialised functions within the cell (Tables S.4, 5.5 and 5.6)(8-, 7). 

In some plants, high PEPCase activities have been detected in specialised tissues or cells, other than the mesophyll cells of C4 and CAM plants. For example, PEPCase is found in guard cells where it is involved in stomatal opening and closing (Tarczynski Outlaw, 1990). The authors concluded, however, that - based on the alterations in chemical environment during stomatal activity - the reactions catalysed could be accomplished by a C3-type PEPCase enzyme and that there was no reason to invoke the existence of isoforms. Less well known is the PEPCase activity and protein detected in reproductive tissues. For example, high PEPCase activity has been observed in seed pods of chickpeas (Singh,... 

Beyond element 92 (U) lie the transuranic elements of the actinide series. These are all artificial but 2< Pu is of interest because it is produced in nuclear reactors from 2 fU and may be released to the environment from accidents or weapons testing. It has a very long half life (2.4 x 104 years) and is a very dangerous alpha emitter, but, like radon, its geochemistry is too specialised to be included in this chapter. Choppin and Stout (1991) have written an overview of the general chemistry of Pu, to mark the 50th anniversary of its original isolation, and Rai et al. (1980) have discussed its soil chemistry. 

Non-ciliated receptors show much variation. Some resemble ciliated receptors in that they have a terminal dendritic bulb with a basal body but no distal cilium (85, 942). Others, as in H. nana (Fig. 2.9), show little structural specialisation and appear to be little more than free nerve endings which may have a single, double or triple structure. Endings which do not penetrate the tegument to the external environment may have a mechanoreceptive or proprioceptive (i.e. receptive to internal stimuli) -rather than chemoreceptive - function (12, 206, 942). 

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