Run distance

Develop the sheet with H2O for about 1.5 h to a height of 16 cm, then dry it and continue development with Solvent 1 to a running distance of 13 cm. Move the sheet in methanol for some minutes and dry it again. Then do the same procedure with Solvent P, followed hy a third run with Solvent 1". 

There are no great changes in corrected Rf values with changes in development distance provided that the system is kept saturated. If it is not, there is an apparent increase in Rf value with increase in running distance due to the increased evaporation of the solvent from the upper parts of the plate. 

Cooper, P. W.,, 4 New Eook at the Run Distance Correlation and Us Relationship to Other Non-Steady-State Phenomena, Proceedings of the Tenth Sjmposium (International) on Detonation, Boston, 1993. 

If a very thin flyer plate were impacted into an explosive, a short or thin pressure pulse would be formed. If the pulse is thin enough, as we shall soon see, the pressure will not be maintained as a constant over the run distance. 

Solution From Table 22.4 we find the Pop-plot or run distance equation for PBX9404 at po = 1.84 g/cm. ... 

We saw that the rarefaction traveling axially into the rear of the shock pulse in an explosive can attenuate the peak shock pressure, and thereby cause longer than ideal run distance or even cause detonation failure. Rarefactions traveling radially into the sides or edges of the impact shock wave can do the same. 

In this manner, the shock is whittled down from the edges, forming a cone-shaped zone that defines the only location where the initial impact shock pressure can endure. The base angle of the cone is determined, approximately, by the ratio of the velocity of the radial rarefaction to the velocity of the axial shock. We saw earlier that the rarefaction velocity is greater than the shock velocity therefore, this base angle must be less than 45°. If the apex distance of this cone is less than the run distance obtained from the Pop-plots, then the actual run... 

Also shown in Figure 22.8 is the pop-plot run distance versus pressure. Note that the minimum diameter for which detonation could be achieved at any given pressure is approximately equal to the ideal run distance at that pressure. Good design practice is to midce sure that detonation is always achieved within the constant pressure cone. Therefore, flyer diameter should always be equal to or greater than twice the run distance. 

Moulard data Wenograd data — Run distance from Pop-plot... 

Solution We saw in Example 22.2 that the run distance for this impact pressure is 2.2 mm. Good design practice is to ensure that the required run distance is equal to or less than the constant-pressure cone height. Since the cone is approximately 45° at the base, the diameter is about twice the height, so our flyer should be 2x2.2 = 4.4 mm diameter at the minimum. 

As you will recall, there must be sufficiently high-energy fluence or P t) and high enough pressure such that the explosive can be initiated in a reasonably short distance from a shock wave input. Electrical constraints limit the practical size (pressure, temperature, time) of the shock obtainable from the bridgewire, and these are such that we require an explosive with very low critical energy fluence, Ec (or and short run distance. PETN, at low density and small... 

The transit time is mainly a function of the particular detonator design, that is, the type, density, and length of the explosives loaded into the detonator. The transit time is equal to the length of each explosive element or pressing, divided by the detonation velocity of that element, plus the excess transit time due to the buildup of run distance to steady-state detonation. Recall that the run distance, and hence excess transit time, is a function of the initiating shock pressure. Also, the initiating shock pressure from an EBW is a function of the burst current. Therefore, the transit time of an EBW detonator is not independent of the system. 

Gradient elution in AMD starts with the most polar eluent and is varied toward decreasing polarity. Figure la shows a typical universal elution gradient, made up of the three solvents methanol, dichloromethane, and hexane. Figure lb illustrates the increasing duration of the development cycles. Time increments are chosen to obtain uniform increases of the running distance of 3 mm/step. 

Rf or "Running distance" values (for explanation of individual values see below)... 

System l46. Heat activated Brinkmann 200 micron silica gel plastic plate ether/N,N-dimethylformamide/acetone/methanol/water (81 12 3 3 1) 2 hours development at 5°C. Detection by U.V.light. Values given are Rf values. System 247. Kieselguhr G plate methylene chloride/dioxane water 2 1 1 Spray reagent Alkaline 2,4-diphenyl-3(4-styrylphenyl)tetrazolium salt "Running distance" values related to cortisone = 1.00. 

System 1 Kieselguhr G plate Dichloroethane/methylacetate/water 2 1 1 Spray reagent Alkaline 2,5-diphenyl-3(4-styrylphenyl) tetrazolium solution "Running distances" values related to cortisone acetate = 1.00 ... 

Running distance" values A,B,C,E related to hydrocortisone acetate =... 

Figure 2. Intensity vs. distance plots for nitrogen titration at 3914 A. FHe = 16.1 X 10 < moles/sec. The intensity was normalized to 100 arbitrary units in all runs. Distance scale 1 unit = 0.531 cm. The number in each run refers to the pressure of nitrogen upstream of the flowmeter orifice and is approximately proportional to the flow rate of nitrogen...

The lAAF (International Association of Athletics Federations) advises to run distance races below 18 °C of WBGT value (F. Yamasawa, IAAF policy on fluid replacement). Clothing is generally not considered in WBGT limits for sports. 

The analogy with the absorbing medium works in comparing the quantity q to the radiation intensity and the advance variable (elapsed time) to the thickness (run distance). As for the absorbing medium that was cut into successive layers in which the decay of radiation was followed by the series of intensities l , I2, , the conversion is divided into sequences of durations Af, M2, At , corresponding to evolving quantities q, q2,..., qn- Each sequence features an amplification or transmission factor +i defined as the ratio of the output on the input quantities. 

Long, J.H. 2008. Research on forecasting methods of the loess landslide with high speed and long-run distance Chang an University Xi an. 

On the basis of the test data, the relation between the shock wave pressure and run-to-detonation distance is finally obtained. The length of the run distances in difierent types of explosives at the same shock wave pressure is the measure of the explosive sensitivity to the shock wave initiation. 

The classes of phospholipids were separated by using n-hexane-2-propanol-water (40 53 7 v/v) eluent mixture. The time of development was only twenty minutes on a 17 cm running distance (68). 

Using optimal eluent front velocity, DL was found to be lower in OPLC than in the case of TLC in consequence of lower band broadening (86) even if the running distance was longer than that in TLC method (87). 

The serial multilayer development ( long-distance OPLC) makes longer running distance possible. Thus, compounds from extremely complex biological matrices can be separated and isolated... 

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