Enhancement effect, method

On the basis of extensive exploratory work,56,57 it proved possible before 1953 to make routine the x-ray emission spectrography of a high-temperature alloy for the determination of five major constituents. The work demonstrated conclusively that this x-ray method offered advantages in respect to convenience, speed, and precision over wet methods for these determinations. It proved that comparison of unknown and standard could satisfactorily compensate the absorption and enhancement effects encountered in these alloys. 

In contrast to that, mentoring is seen as an effective method of enhancing the development of people, precisely because it t)q)ically improves both learning retention as well as the transfer of the learned information to real life situations (e.g. the workplace). Emphasizing the motivation for adopting mentoring, Jossi (1997) points out that ... 

Retention of staff, in whom a lot had been invested, was enhanced. Mentoring was a cost-effective method. 

It can be seen from Figures 3.7 and 3.8 that the calculations reproduce very well not only the experimental spectra but also the experimentally observed isotopic shifts indicating a high reliability of the computational method. According to this comparison, definite attribution can be made for even the difficult Raman bands that cannot be assigned based solely on the experimental results. It is, however, necessary to mention at this point that the calculated Raman spectrum provided directly by the ab initio computations correspond to the normal Raman spectrum with the band intensity determined by the polarizability of the correlating vibration. Since the intensity pattern exhibited by the experimentally recorded resonance Raman spectrum is due to the resonance enhancement effect of a particular chromophore, with no consideration of this effect, the calculated intensity pattern may, in many... 

XRF nowadays provides accurate concentration data at major and low trace levels for nearly all the elements in a wide variety of materials. Hardware and software advances enable on-line application of the fundamental approach in either classical or influence coefficient algorithms for the correction of absorption and enhancement effects. Vendors software packages, such as QuantAS (ARL), SSQ (Siemens), X40, IQ+ and SuperQ (Philips), are precalibrated analytical programs, allowing semiquantitative to quantitative analysis for elements in any type of (unknown) material measured on a specific X-ray spectrometer without standards or specific calibrations. The basis is the fundamental parameter method for calculation of correction coefficients for matrix elements (inter-element influences) from fundamental physical values such as absorption and secondary fluorescence. UniQuant (ODS) calibrates instrumental sensitivity factors (k values) for 79 elements with a set of standards of the pure element. In this approach to inter-element effects, it is not necessary to determine a calibration curve for each element in a matrix. Calibration of k values with pure standards may still lead to systematic errors for unknown polymer samples. UniQuant provides semiquantitative XRF analysis [242]. 

In such cases, the MEHMC method could be employed in combination with an enhanced sampling method that deforms the effective energy surface (but preserves the location of the potential minima), such as that in [29, 97]. Likewise, it may be worthwhile to explore the use of a reversible multiple-time-scale molecular dynamics propagator [103] with MEHMC to accelerate the dynamical propagation. 

To check the enhancement effect in the presence of soil extracts, soil was treated with ammonium nitrate at a rate equivalent to 200kg ha-1. When 50g of the soil were extracted with 100ml of methanol using the method of Byast et al. [101] the concentration of ammonium nitrate in solution was about 4pg pL-1. Injections of the treated soil extract increased the peak height of a subsequent 60ng Atrazine standard by 55-65%. No increase occurred following injections of untreated soil extracts. 

It has been suggested that microbial cata holism of off-flavor metabolites may be enhanced to provide an effective method ) control off-flavors. Indeed, microbial cultures have been reported to degrade relatively high levels of off-flavor metabolites (53, 54, 55), but whether microbial activity can be used practically to improve the flavor quality of aquaculture systems remains to be determined. 

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