Spray measurements with the time-shift technique

Surface sampling with an agar spray technique.

New method to improve the accuracy of group delay measurements using the phase-shift technique

We propose and demonstrate a novel method to improve the accuracy of measurements of group delays using the conventional phase-shift technique. In particular, the method allows for accurate reconstruction of the actual group delay when a high modulation frequency is employed to increase the timing resolution. The method is based on postprocessing of the measured data in a deconvolution operatio...

Chemical Shift Measurements

Several inconsistencies have been noted during recent systematic studies of the validity of additivity relationships (1-6) in the C chemical shifts of substituted pyridines. These showed that substantial errors could be introduced if care is not taken to use, for a given solvent, approximately the same concentration for all solutes; in our case this applied to monosubstituted and polysubstitute...

The application of a shift theorem analysis technique to multipoint measurements

A Fourier domain technique has been proposed previously which, in principle, quanti®es the extent to which multipoint in-situ measurements can identify whether or not an observed structure is time stationary in its rest frame. Once a structure, sampled for example by four spacecraft, is shown to be quasistationary in its rest frame, the structure's velocity vector can be determined with respect...

the effect of task cognitive complexity and time limit on the performance of the learners with different proficiency levels in second language writing skill

this study investigated the effects of manipulating the cognitive complexity of tasks along +/- few elements and the time limits on l2 learners writing performance. to conduct the study, 60 iranian efl learners with two levels of proficiency, low and high intermediate, were selected and assigned to three groups based on the time devoted to task completion. the participants performed both a simp...