Laboratory simulator

Fig. 7.13 Influence of coal chlorine content on the corrosion rates of low-alloy steels exposed to laboratory simulation of furnace wall corrosion (Brooks, C.E.G.B., private communication)...

Karlson et found, from on-site experience of cement-producing plant, that corrosion of Fe surfaces may occur in gases containing O2, SO2 and alkali chlorides such as NaCl and KCl between 300°C and 500°C. They reported that the corrosion rates may be extraordinarily high (5-10 mm/ month) implying liquid-phase corrosion. Laboratory simulation of the plant conditions demonstrated the need for both SO2 and the alkali chloride in the environment. The principle corrosion reaction was found to be ... 

Determination of the nature of the sulfate content was attempted by following the conch of this impurity in two ways (1) during the course of laboratory simulated industrial stabilization procedures, and (2) from successive dissolutions of unstabilized NC samples in various solvents and subsequent repptn from non-solvents. This approach was based on the premise that free occluded sulfuric acid would be released from the fibers by the soln-pptn treatment, whereas chemically combined sulfate would remain unaffected. The fuli details of the various expts can be found in Ref 5 some typical results are shown in Table 3 for four samples of NC of different nitrogen content... 

J) Anon, Laboratory Simulation Symposium, 26—27 October 1967 , Rept No NATC-WST-38-00 (1967) K) Anon, Defence Investigation Reports (Swed), Rept No RAE-Library Trans-1312, RAE (Engl) (1968)... 

The modules are computer-based laboratory simulations with engaging activities that emphasize experimental design and visualization of structures and processes at the molecular level. The modules are designed to help students connect chemical principles from lecture with their practical applications in the lab. Every module has a built-in accountability feature that records section completion for use in setting grades and a workbook for students to record and interpret their work. 

Further to aspects discussed in Section 23.5.1.2, the simplest strategy, if it is practical, is slow decompression. If the pressure can be reduced sufficiently slowly, the gas which is dissolved in the elastomer can diffuse out of the mbber without buUding up sufficient internal pressure to cause damage. The rate of decompression required may be roughly calculated if the diffusion coefficient of the gas and its solubility in the elastomer are known— but in practice it will probably require a laboratory simulation. 

An experiment on toluene biodegradation under field and laboratory conditions provided results of value in the design of laboratory simulation experiments, and illustrated the caution required in assessing the fate of contaminants. Experiments were carried out under three conditions (i) in flow-through horizontal columns containing sediment and rocks, (ii) in shaking cultures containing sediments, rocks, or plant material, and (iii) in situ in a contaminated stream (Cohen et al. 1995). There were a number of important conclusions ... 

The NACE Landrum Wheel velocity test, originally TM0270-72, is typical of several mechanical-action immersion test methods to evaluate the effects of corrosion. Unfortunately, these laboratory simulation techniques did not consider the fluid mechanics of the environment or metal interface, and service experience very seldom supports the test... 

C. Durand, A. Onaisi, A. Audibert, T. Forsans, and C. Ruffet. Influence of clays on borehole stability A literature survey Pt 2 Mechanical description and modelling of clays and shales drilling practices versus laboratory simulations. Rev Inst Franc Petrol, 50(3) 353-369, May-June 1995. 

Klaessens [14-17] developed a laboratory simulator , written in SIMULA, which by a question-answering session assembles the simulation model. SIMULA [18] is a programming environment dedicated to the simulation of queuing systems. KEE [ 19] offers a graphics-driven discrete event simulator, in which the objects are represented by icons which can be connected into a logical network (e.g. a production line for the manufacturing of electronic devices). Although KEE has proven its potential in many areas, no examples are known of analytical laboratories simulated in KEE. 

Ahmed, U., et al. "Effect of Stress Distribution on Hydraulic Fracture Geometry A Laboratory Simulation Study in One Meter Cubic Blocks," SPE/DOE paper 11637, 1983 SPE/DOE Symposium on Low Permeability, Denver, March 14 16. 

Laboratory simulation experiments with a helium cryostat at temperatures of around 10 K and pressures of 10-8 mmHg, which have been carried out in particular by Majo Greenberg at the University of Leiden in Holland (Greenberg, 1983). 

Criticisms of laboratory simulation experiments (which generally last between several hours and a few days) are often based on statements made on the basis of extrapolation of the experimental results to cover processes in outer space, i.e., judgements based on experiments taking 2-3 days are made on processes occurring in outer space which can take many million years. In this case, the Bacillus subtilis research can offer one very positive experiment, as the space mission LDEF took almost six years to complete. 

P.E. Hare, R.M. Mitterer, Laboratory Simulation of Amino Acid Diagenesis in Fossils, Carnegie Institution of Washington Year Book, 67, 205 208 (1969). 

Formica, S.J., Baron, J.A., Thibodeaux, L.J., Valsaraj, K.T. (1988) PCB transport into lake sediments. Conceptual model and laboratory simulation. Environ. Sci. Technol. 22, 1435-1440. 

Engine compression ratios, 12 395 Engine conditions, laboratory simulation tests of, 12 401... 

Evershed, R.P. and Charters, S. (1995). Interpreting lipid residues in archaeological ceramics preliminary results from laboratory simulations of vessel use and burial. Materials Research Society Symposia Proceedings 352 85-95. 

Sorption and/or desorption processes, a part of the removal/reduction/ retardation (RRR) processes for chemical constituents in leachates, were determined by a testing methodology using a series of laboratory simulations. 

It is interesting to note that stratified combustible gas mixtures can exist in tunnel-like conditions. The condition in a coal mine tunnel is an excellent example. The marsh gas (methane) is lighter than air and accumulates at the ceiling. Thus a stratified air-methane mixture exists. Experiments have shown that under the conditions described the flame propagation rate is very much faster than the stoichiometric laminar flame speed. In laboratory experiments simulating the mine-like conditions the actual rates were found to be affected by the laboratory simulated tunnel length and depth. In effect, the expansion of the reaction products of these type laboratory experiments drives the flame front developed. The overall effect is similar in context to the soap bubble type flame experiments discussed in Section C5c. In the soap bubble flame experiment measurements, the ambient condition is about 300 K and the stoichiometric flame temperature of the flame products for most hydrocarbon fuels... 

The importance of equilibrium versus kinetic effects has yet to be addressed in any coherent way by the limited laboratory experiments conducted for Li isotope study. It is clear from the study of other stable isotope systems that kinetic effects may dominate the fractionation pathways under many circumstances (e.g., Johnson and Bullen 2004), especially in laboratory simulations of low-temperature natural phenomena (Beard and Johnson 2004). The clarification of how kinetic effects on Li isotopic compositions are manifested remains a major area for future study in natural, synthetic and theoretical systems. 

These generalizations regarding high-temperature fluid-rock reactions are based on field observations and laboratory simulations. Geochemists have attempted to run high-temperature reactions in the lab by reacting basalt with seawater at pressures up to 1000 bar and temperatures of 70 to 500°C at rock-to-water ratios from 1 to 62 for periods as long as 20 months. Their reaction products support the conclusions made from field observations. 

The review of the experimental toxicology of photochemical oxidants in this chapter is therefore primarily a review of the toxicology of ozone. The reader should bear in mind that what is said about ozone may not apply in every case to the broader term photochemical oxidants, but, given the current state of knowledge, ozone toxicology is the best approximation of the toxicology of the class. With this in mind, it is of value to review briefly the experimental toxicolc of complex mixtures of ambient or laboratory-simulated photochemical smog. 

Wang, L.K. Laboratory Simulation and Optimization of Water Treatment Processes, PB88-168414/ AS US Department of Commerce, National Technical Information Service Springfield, VA, 1986 54 p. 

Wang, L.K. Laboratory simulation of water and wastewater treatment processes. Water Treatment, 1995, 10, 261-282. 

Shy, S.S., R. H. Jang, and P. D. Ronney. 1996. Laboratory simulation of flamelet and distributed models for premixed turbulent combustion using aqueous auto-catalytic reactions. Combustion Science Technology 113 329-50. 

Peters KE, Rohrbach BG, Kaplan IR (1981) Carbon and hydrogen stable isotope variations in kerogen during laboratory-simulated thermal maturation. Am Assoc Petrol Geol Bull 65 501-508... 

Sackett WM (1978) Carbon and hydrogen isotope effects during the thermocatalytic production of hydrocarbons in laboratory simulation experiments. Geochim Cosmochim Acta 42 571-580 Sackett WM, Thompson RR (1963) Isotopic organic carbon composition of recent continental derived clastic sediments of Eastern Gulf Coast, Gulf of Mexico. Bull Am Ass Petrol Geol 47 ... 

A stndy was made of the effects of foam formulation and process conditions and liner composition on the adhesion of HCFC-141b blown rigid PU foam thermal insulation to refrigerator liner protective layers made of ABS, high-impact PS (HIPS), PE and blends of HIPS and PE containing a compatibiliser and adhesion promoter. A tensile test was used to quantify the level of adhesion before and after thermal cycling, and the Brett mould was used for laboratory simulations of foam adhesion within... 

In fact, there is a recognition that a range of different test data may be required to support label claims. An applicant for authorisation of a biocidal product can confirm their efficacy claim with the provision of data from simple laboratory studies, laboratory simulated-use tests, pilot system studies or field studies according to either standard and/or non-standard test methods. 

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