Temporal resolving power

To demonstrate the temporal resolving power of our Instrument Figure 5 shows multifrequency phase and modulation plots for a binary mixture of fluorescein and ubrene. A single exponential fit to the data (not shown) yields ay of 19 and residual errors that deviate in a systematic pattern. However, when the data are fit to a double exponential decay model, the recovered lifetimes of 3 and... 

To begin with, we must specify the spectral window we are referring to and then use the appropriate detector telescope, radiotelescope or space-borne observatory. The next characteristic is the accuracy of the energy, frequency or wavelength measurement, followed by the accuracy of the angular measurement (resolving power), and the temporal resolution and sensitivity of the measurement. Finally, we note the direction, date and duration of the observation for each particular celestial object we choose to investigate. 

This work by Heidelberg has been significant in that it demonstrated for the first time that TDL sensors can provide temporally resolved in situ measurements of temperature and species concentrations in the combustion zone of a coal-fired power plant. These measurements are not attainable using conventional sensors. Perhaps even more importantly, the body of work by Heidelberg demonstrates that TDL sensors can be made rugged enough to survive harsh industrial environments, including waste incinerators and power plants. 

The temporal property of an orbitrap is similar to that of an ICR mass analyzer. The mass resolving power relies on the length of the transient, so the SAT required to record a high-resolution spectrum is typically 1 -10 s. The SAT can be reduced to < 1 s if low or medium mass resolving power is acceptable. 

Exploitation of time-resolved spectroscopy allows the direct observation of the reactive intermediates (i.e., ion-radical pair) involved in the oxidation of enol silyl ether (ESE) by photoactivated chloranil (3CA ), and their temporal evolution to the enone and adduct in the following way.41c Photoexcitation of chloranil (at lexc = 355 nm) produces excited chloranil triplet (3CA ) which is a powerful electron acceptor (EKelectron-rich enol silyl ethers (Em = 1.0-1.5 V versus SCE) to the ion-radical pair with unit quantum yield, both in dichloromethane and in acetonitrile (equation 20). 

Since both electronic and dynamic components can be measured, the choice of the laser pulse width is very important to determine which components will be measured. In organic materials, the peak power is usually in the 10 MW/cm- — 1 GW/cm range. The laser pulses have to be well resolved temporally and spatially and pulse fluctuations should be minimized. With long laser... 

Emission measurement from the excited states is also a powerful method to investigate the ion beam radiation chemistry because a very sensitive time resolved photon-counting technique can be applied. In 1970s, temporal behavior of the emission from benzene excited states in 40 mM benzene in cyclohexane irradiated with pulsed proton and He ion particles was measured and compared with UV pulse irradiation. It was found that immediately after the irradiation there is a short decay (< 10 ns) followed by a longer decay corresponding to the life-time of the benzene excited states (26-28 ns). The fraction of the shorter decay component increases with increasing LET of the particle. This was explained by a quenching mechanism that radical species formed in the track core attack and quench the benzene excited states, which would take place only shorter period less than 10 ns after irradiation [69]. 

Formation and decay of transient intermediates constitute a phenomenon that is ubiquitous to enzyme catalysis. Time-resolved UV/visible optical spectra which document the absorbance spectral changes that accompany the conversion of chromophoric reactants to final products by way of transient intermediates have the potential for identification of these transient species. The RSSF experiment provides three-dimensional data sets consisting of optical absorbance as a function of both wavelength and time. Owing to the temporal nature of the acquired data, an RSSF experiment can be a powerful tool for sorting out the timing of intermediate formation and decay with respect to other events that take place during... 

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