Search results for "INTERFERENCE"

Determination of Calcium in Certain Fertilizers by Inductively Coupled Plasma Atomic Emission Spectrometry: Studies of Some Spectral and Interelement…

1997

Abstract Four analytical wavelengths (393.366, 396.847, 317.933, and 422.673 nm) were used to determine Ca in 2 fertilizers by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Matrix effects were studied by adding to real fertilizer solutions fertilizer elements that are known or believed to interfere with Ca determination. Matrix effects were calculated by multiple linear regression. Interference was caused by S, K, or B. At 422.673 nm, the interference of B and K is a spectral effect, and at 396.847 and 317.933 nm, the interference of S and K is an interelement effect. At 393.366 nm, no linear interference was found. The best wavelength for determining Ca in fertilizers …

Iron Determination in Fertilizers by Inductively Coupled Plasma Atomic Emission Spectrometry: Study of Spectral and Interelement Effects at Different…

1996

Abstract Four analytical wavelengths of iron (238.204, 239.562, 259.940, and 240.488 nm) were tested for determination of Fe in fertilizers by inductively cou pled plasma atomic emission spectroscopy (ICP AES). Variations in measurements were caused by the changing interference pattern at different wave lengths evaluated by multiple linear regression. Thus, results obtained with different wavelengths are not comparable. Ca, P, and K were typical ele ments causing interference in almost all examined Fe wavelengths. Wavelength Fe II 238.204 nm is the best wavelength for determination of Fe in fertiliz ers by ICP-AES. Method accuracy is ± 8% at the ex amined Fe levels in fertilizers.

Determination of Boron in Fertilizers by Inductively Coupled Plasma-Atomic Emission Spectrometry: Studies of Some Spectral Interferences at Different…

1995

Abstract The most sensitive analytical wavelengths of boron cannot be used in the determination of boron in fertilizers by inductively coupled plasma-atomic emission spectrometry because of spectral interference by potassium, phosphorus, and iron. For the 4 wavelengths of boron investigated, it was noticed that, at the same wavelength, the pattern of spectral interference changes according to fertilizer composition. The spectral interference patterns at the 4 analytical boron wavelengths were studied by adding matrix elements typically found in fertilizers to real fertilizer samples. When levels of added matrix elements correlate less than 0.2 to each other, the effect of added matrix eleme…

Determination of Sulfur in Fertilizers by Inductively Coupled Plasma-Atomic Emission Spectrometry: Spectral and Interelement Effects at Various Wavel…

1996

Abstract Three analytical wavelengths (180.731,182.037, and 182.625 nm) were tested for determination of sulfur in 2 fertilizers by inductively coupled plasmaatomic emission spectrometry (ICP-AES). Variable S results at 182.037 nm were caused by a downward sloping background shift (Fe line at 181.851 nm) during measurement of the sample solutions. At 182.625 nm an emission peak doublet, 182.619/182.635 nm, was observed from which the instrument selected the measurement peak. A shift from calibrated peak 182.619 nm to noncalibrated peak 182.635 nm occurred when the S/B ratios were ≤22-31 in the fertilizer samples examined. For the 3 wavelengths of S investigated, the pattern of spectral and …

Inhibiting proliferation in KB cancer cells by RNA interference-mediated knockdown of nicotinamide N-methyltransferase expression.

2011

The enzyme Nicotinamide N-methyltransferase (NNMT) catalyzes the methylation of nicotinamide and other pyridines, playing a pivotal role in the biotransformation and detoxification of many drugs and xenobiotic compounds. Several tumours have been associated with abnormal NNMT expression, however its role in tumour development remains largely unknown. In this study we investigated expression levels of Nicotinamide N-methyltransferase in a cancer cell line and we evaluated the effect of shRNA-mediated silencing of NNMT on cell proliferation. Cancer cells were examined for NNMT expression by semiquantitative RT-PCR and Western blot analysis. A HPLC-based catalytic assay was performed to asses…

Study of ordered hadron chains with the ATLAS detector

2017

The analysis of the momentum difference between charged hadrons in high-energy proton-proton collisions is performed in order to study coherent particle production. The observed correlation pattern agrees with a model of a helical QCD string fragmenting into a chain of ground-state hadrons. A threshold momentum difference in the production of adjacent pairs of charged hadrons is observed, in agreement with model predictions. The presence of low-mass hadron chains also explains the emergence of charge-combination-dependent two-particle correlations commonly attributed to Bose-Einstein interference. The data sample consists of 190 μb-1 of minimum-bias events collected with proton-proton colli…

The UWB-OFDM Channel Analysis in Frequency

2009

In this paper, the ultra-wideband channel with orthogonal frequency division multiplexing (UWB-OFDM) is analyzed in the frequency domain. For UWB-OFDM channels with log-normal fading in the time domain, we show that the amplitude of each subcarrier can be approximated by a Nakagami-m random variable, where the fading parameter, the mean power and the correlation coefficient are expressed in terms of the following parameters: time arrival of the clusters, inter-arrival time of rays inside clusters, and power decay constants of rays and clusters.

INTERFERENCE REMOVAL IN ICP-MS USING HE COLLISION CELL WITH TANDEM MS

2021

Interference Effects in Photodetachment of F- in a Strong Circularly Polarized Laser Pulse

2007

A numerical simulation of photodetachment of F{sup -} by a circularly polarized laser pulse has been accomplished by using a Keldysh-type approach. The numerical results are in agreement with measurements of photoelectron energy spectra recently reported in the literature. The features exhibited by the spectra are traced back to quantum interference effects, in the same spirit as in a double-slit experiment in the time doma0008.

Visibility of Young's interference fringes: Scattered light from small ion crystals

2015

We observe interference in the light scattered from trapped $^{40}$Ca$^+$ ion crystals. By varying the intensity of the excitation laser, we study the influence of elastic and inelastic scattering on the visibility of the fringe pattern and discriminate its effect from that of the ion temperature and wave-packet localization. In this way we determine the complex degree of coherence and the mutual coherence of light fields produced by individual atoms. We obtain interference fringes from crystals consisting of two, three and four ions in a harmonic trap. Control of the trapping potential allows for the adjustment of the interatomic distances and thus the formation of linear arrays of atoms s…