Short-term measurements

The successflil appHcation of time—temperature superposition (159) for polystyrene foam is particularly significant in that it allows prediction of long-term behavior from short-term measurements. This is of interest in building and constmction appHcations. 

Drager tubes for short-term measurements DrSger tube Range of measurement (2(fC, 1013 mbar)... 

ISO 15686-2 describes the methodology of estimating service lives based on experience, short-term measurement and accelerated testing, in that order. All possible degradation agents and their intensities are listed. Methods for evaluation and for pre-testing (control... 

In a French fibre plant, short-term measurements (< 2 h) were taken at the grinding... 

The effluent disposal scheme adopted is a short term measure only and long term disposal mode is being studied In detail. 

Each situation requires an evaluation of the hypotheses to be tested before the personal monitor can be designed and the identification of the types and duration of exposure that may occur. Once inhaled, the compound may be rapidly metabolized in the body short-term measurements would be appropriate for such processes. The compound may instead have a long residence time at a specific site in the lung or may be stored in an organ or tissue. Thus, the inhaled compound or one or more of its adducts or metabolites could eventually deliver a biologically effective dose to a target organ or cell (13). The monitor must be developed with consideration of the... 

Pyrite is formed by two mechanisms in freshwater sediments. Fram-boidal pyrite results from reaction of iron monosulfides with S° (15), a slow reaction leading to gradual conversion of iron monosulfides to pyrite. In contrast, single crystals of pyrite are formed rapidly through reaction of Fe2+ and poly sulfides (161). Framboidal pyrite has been reported in lake sediments (37, 189), where it appears to form in microenvironments of plant or animal skeletons (cf. 35, 36). Rapid formation of pyrite has been observed in short-term measurements of sulfate reduction with SO/-. Up to 90% of reduced has been observed in pyrite after incubations of 1-24 h (72, 79, 98). A large fraction of inorganic S in the form of pyrite in surface sediments also has been interpreted to indicate rapid formation (112, 190). As discussed later, there is little evidence for extensive conversion of monosulfides to pyrite. 

The military interest in alternative fuels proposes to focus on Fort Leonard Wood as part of the alternative fuels test bed. The military s interest stems from economic reasons and meeting a Presidential challenge to achieve a very short-term measured objective to achieve a shift to 3% of fuels used as renewable fuels. The economic reasons are further defined in environmental, operating as well as public relations costs. UMR is also... 

However for short term measurements this means an excellent way to overcome the mentioned problems. 

Li, F., Conroy, E., Visscher, M., and Wickett, R.R. The ability of electrical measurements to predict skin moisturization. I. Effects of NaCl and glycerin on short-term measurements. J. Cosmet. Sci. 2001 52 13-22. 

In addition to mass trapping, felling and removal of beetle-infested trees was the main short-term measure. It was strongly recommended that infested trees should be removed from the forest in June-July before the adult of the next generation had emerged. Traps were to be deployed preferably in areas with minor infestation, one trap for every 3-5 trees killed by the beetle the previous year. Trapping was not recommended for saving old stands with extensive beetle infestation or stands severely weakened by... 

Drager tubes for short-term measurements Drager tube... 

Henderson S. A., Voncaemmerer S., and Farquhar G. D. (1992) Short-term measurements of carbon isotope discrimination in several C4 species. Austral. J. Plant Physiol. 19(3), 263-285. 

In the individual case, these short-term measures (possibly also reinfusion of ascitic fluid) lead to a temporary improvement of hypoalbuminaemia and hypovolaemia, so that a diuretic therapy, which has been hitherto insufficient, can nevertheless be continued and successfully completed. If stages I-III fail to be efficacious in eliminating ascites, paracentesis is indicated. 

It is important to recognize that short term measures, while essential, will not bring a total solution. While the Bush administration is supporting measures such as hybrid vehicle tax credits, ethanol production, and revisions in fuel efficiency standards, these interim strategies will not ultimately reverse our dependence on foreign oil or address environmental problems as hydrogen can. 

The economic and social consequences of Inadequate lifetime predictions are well documented. It would be reassuring if every kind of material sample or product could be tested to determine expected lifetime under all possible service conditions, but the time and resources required to do so ustially makes this approach Impractical. Therefore, the results of short-term measurements and tests must be Incorporated into most lifetime prediction schemes. 

The need for Improved prediction capabilities Is addressed by (1) Investigating the relationship between present properties of a material, the history of these properties, and the future performance of the material by (2) developing short-term measurement and test methods to forecast the long-term performance of materials, and by (3) constructing basic models for predicting lifetime performance of materials. 

Short-term measurements are based on the relation between current and voltage. It is possible to observe the system and wait for a defined event (e.g., open-circuit operation, starting of an engine, etc.), or it is possible to inject a defined current and measure the voltage response. Most methods are based on an electric circuit that consists of a voltage source, an over-voltage network, and a side-reaction current (Fig. 8.9). 

Because one has to consider unpredictably higher concentrations, especially in the case of the last two jobs mentioned, the use of respiratory protection is often necessary. For selection of the most suitable devices, concentration measurements have to be performed. It is important to consider the surrounding environment of workplaces if other persoimel occasionally work in these areas without respiratory protection. If jobs are of short duration, short-term measurements need to be performed to assess the exposure. A risk assessment of short-term exposures on the basis of an 8-h measurement is only possible in exceptional cases. For short-term exposure measurements, not every sampling technique is suitable. In this case, special sampling methods must be used in order to achieve a sufficiently low detection limit during short measurement times, especially for complex mixtures of substances. In many cases of this type thermodesorption has been proved to be the method of choice. 

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