Wave-length effect

The mixture of acetonitrile/water (1 1, v/v) was selected as most effective mobile phase. The optimum conditions for chromatography were the velocity of mobile phase utilization - 0,6 ml/min, the wave length in spectrophotometric detector - 254 nm. The linear dependence of the height of peack in chromathography from the TM concentration was observed in the range of 1-12.0 p.g/mL. 

A with a max at 3800A. The absorption overlap of the nitrocompds is plainly evident. The position and slope of each curve in Fig 1 can be qualitatively correlated with the absorption range and % transmittance at the peak for each compd. Nitro me thane, which absorbs more at shorter wave lengths and exhibits the least overlap of the toluene-PPO emission spectrum, accordingly has the least effect on the count Tate of the pure scintiliator... 

For arrangements (a) and (b) the structure factor in the first order is 4Ba for planes with hSG even and kSG + lSG even, and 0 for all other planes. These arrangements are definitely eliminated by the experimental data for example, (411)SG is absent, and (521)sg> with smaller interplanar distance, reflects very strongly at the same wave length. Such wide discrepancies cannot be explained as due to the effect of sulfur and oxygen atoms. The barium atoms are, therefore, located as in (c). Because of the presence of other atoms no attempt was made to determine the two parameters involved. 

The theoretically obtained electron densities of ions may be used for the calculation of the so-called F curves, which give the effective reflecting power of the ion as a function of the angle of reflection and the wave-length of X-rays, and which are of use in the determination of crystal structures. It may be mentioned that the high maximum value of the electron density at the nucleus given by our calculations provides considerable justification for the method of determining crystal structures with the aid of the relative intensities of Laue spots produced by crystal planes with complicated indices. 

Thus the photochemical combination of hydrogen and chlorine over the longer of the wave-lengths to which it is sensitive appears to illustrate Tolman s theory in its simplest form, the influence of temperature being in an important part its effect on the absorption of light by the photo-chemically active constituent. 

It is frequently necessary to subtract from the total absorption a part owing to the un-ionized molecule in measuring the amount of ion present. If a given solute exists in two forms, such as a molecule and an ion, it is quite likely that the absorption curves of the two forms will intersect at some point. The intersection is known as an isobestic point, and at the wave length of the isobestic point the extinction depends only on the total amount of solute and not on the proportion of the two forms.166 One investigator who had the bad luck to pick the isobestic wave length for all his experiments came to the mistaken conclusion that it was not possible to determine the position of his particular equilibrium by optical means. A medium effect will cause a family of absorption curves to intersect in a small region rather than in a point, but failure to show an isobestic point even approximately means that the solute exists in more than two forms. 

The most important difference between the two transitions is the effect of solvent on the wave length of the peak. 

Due to steric hindrance by cis substituents, coplanarity and conjugation of cis polymers is hindered. As a result the absorption of trans polyenes occurs at higher wave lengths compared with the absorption of cis polyenes. The same effect is observed in cis trans stilbenes. 

The short wave-length limit of the X-radiation produced by the above difference of potential of 11,890 volts was 1.040 A. The point to be decided by these experiments was how close to this particular wavelength limit the average, or effective wave-length of the beam of X-rays coming from the mercury vapor really lay. 

In order to determine the effective wave-length of the radiation coming from the mercury through the window of the X-ray tube the sheet of aluminum, calibrated as described, was placed between the tube and ... 

The effective wave-length, e, of a beam of X-rays may be defined by the following equation ... 

If we calculate the effective wave-length of a band in the spectrum of uniform intensity, J, extending from X = 1.04 to X = 1.16, in other words, a band about 10% in width, we find that its value is e = 1.10. Hence, the beam of X-rays actually coming from the mercury through the window... 

For a building with a flat roof (pitch less than 10°) it is normally assumed that reflection does not occur when the blast wave travels horizontally. Consequently, the roof will experience the side-on overpressure combined with the dynamic wind pressure, the same as the side walls. The dynamic wind force on the roof acts in the opposite direction to the overpressure (upward). Also, consideration should be given to variation of the blast wave with distance and time as it travels across a roof element. The resulting roof loading, as shown in Figure 3.8, depends on the ratio of blast wave length to the span of the roof element and on its orientation relative to the direction of the blast wave. The effective peak overpressure for the roof elements are calculated using Equation 3.11 similar to the side wall. 

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