Domains whose overrings satisfy accp

An integral domain D satisfies ACC on principal ideals (ACJCP) if there does not exist an infinite strictly ascending chain of principal ideals of D. Any Noetherian domain, in particular any Dedekind domain, satisfies ACCP. In this note we prove the following theorem: Let D be an integral domain. Then the integral closure of D is a Dedekind domain if and only if every overring of D (ring between D and its quotient field) satisfies ACCP.     

Integral Domains Having Nonzero Elements with Infinitely Many Prime Divisors

In a factorial domain, every nonzero element has only finitely many prime divisors. We study integral domains having nonzero elements with infinitely many prime divisors.     

Soliton collisions with wavelength-division multiplexed systems with strong dispersion management

We investigate collisions between solitons in a lossless two-channel wavelength-division multiplexed system with strong dispersion management. Numerical results show that the net frequency shift that is due to interchannel collisions is at least 1 order of magnitude smaller than predicted by adiabatic theories. A modified theoretical analysis is presented and shown to be in good agreement with the numerical results.     

Preliminary investigation of a medium power argon radiofrequency capacitively coupled plasma as atomization cell in atomic fluorescence spectrometry of cadmium

The single ring electrode radiofrequency capacitively coupled plasma torch (SRTr.f.CCP) operated at 275W, 27.12 MHz and Ar flow rate below 0.7 lmin(-1) was investigated for the first time as atomization cell in atomic fluorescence spectrometry (AFS) using electrodeless discharge lamps (EDL) as primary radiation source and charged coupled devices as detector. The signal to background ratio (SBR) and limit of detection for Cd determination by EDL-SRTr.f.CCP-AFS were compared to those obtained in atomic emission spectrometry using the same plasma torch. The detection limit in fluorescence was 4.3 ngml(-1) Cd compared to 65 ngml(-1) and 40 ngml(-1) reported in r.f.CCP-atomic emission (AES) equipped with single or double ring electrode. The lower detection limit in EDL-SRTr.f.CCP-AFS is due to a much better SBR in fluorescence. The limit of detection was also compared to those in atomic fluorescence with inductively coupled plasma (0.4 ngml(-1)), microwave plasma torch (0.25 ngml(-1)) and air-acetylene flame (8 ngml(-1)). The influence of light-scattering through the plasma and the secondary reflection of the primary radiation on the wall of the quartz tube on the analytical performance are discussed. The non-spectral matrix effects of Ca, Mg and easily ionized elements are much lower in EDL-SRTr.f.CCP-AFS compared to SRTr.f.CCP-AES. The new technique was applied in the determination of Cd in contaminated soils, industrial hazardous waste (0.4-370 mgkg(-1)) and water (113 microgl(-1)) with repeatability of 4-8% and reproducibility in the range of 5-12%, similar to those in ICP-AES. The results were checked by the analysis of a soil and water CRM with a recovery degree of 97+/-9% and 98+/-4%, for a confidence limit of 95%. The present EDL-SRTr.f.CCP-AFS is a promising technique for Cd determination in environmental samples.     

Validation of the Tessier scheme for speciation of metals in soil using the Bland and Altman test

The Tessier extraction method was used for speciation of Cu, Pb, Zn, As, Fe and Mn in a large concentration range in contaminated soil with various mineralogical compositions. The results were compared by X-ray fluorescence spectrometry (XRF) as a reference method using the Bland and Altman test. A sum of five fractions (exchangeable, bound to carbonates, Fe-Mn oxides, organic matter and residual forms) was compared with the total content determined on solid matrix by the reference method. A good agreement between the methods in the whole concentration range was found for Cu, Zn, As, and Fe. For Mn and Pb, XRF was found suitable to verify the sequential extraction only for concentrations above 250 mg kg⁻¹. This was a consequence of a poorer reproducibility of Pb extraction using the Tessier scheme due to a great difference in the mineralogical composition and the diversity of the Pb species identified in soil. The poorer result of Mn was attributed to the spectral interference of Fe in XRF. Presented at the 34th International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 21–25 May 2007.     

Constraining chameleon field driven warm inflation with Planck 2018 data

The European Physical Journal C - We study the Yukawa model with one scalar and one axial scalar fields, coupled to N copies of Dirac fermions, in curved spacetime background. The theory possesses...     

The use of stable isotopes ratios for authentication of fruit juices

The determination of the content of stable isotopes, ¹⁸O and ²H, respectively, in juice water facilitates the distinction between authentic juices and juices made from concentrates by redilution with tap water. At the same time, the detection of C₄ cane or corn-derived sugar syrups in fruit juices which are produced from C₃ fruit types is thus facilitated by the characteristic differences in ¹³C/¹²C, expressed as δ ¹³C (‰) values due to photosynthetic CO₂ assimilation via the C₃₋, C₄₋, and crassulacean acid metabolism pathways. In this study, the quantitative determination of water added to an authentic juice, on the basis of δ ¹⁸O, and δ ²H values, respectively, was successfully performed. Also, the δ ¹⁸O, and δ ²H of juice water and δ ¹³C of the whole juice in 18 samples were also determined. The results obtained provided us with the possibility of distinguishing between authentic fruit juices and those obtained by redilution of concentrated fruit juices and the detection of C⁴ type added sugar.     

Timing-jitter reduction in a fiber laser mode locked by an input bit stream

We present analytical and numerical results for the amount of timing-jitter reduction obtained in an all-optical clock-recovery device in which a data stream is used to mode lock a fiber laser through cross-phase modulation. This situation is analyzed when the laser pulses are close to optical solitons, so the effect of the data stream on the laser pulses is predicted from soliton perturbation theory. In our numerical simulations, both periodic input and pseudorandom input data streams are considered. The results show that for both types of data the rms timing jitter in the recovered clock is reduced significantly from that present in the input data.     

Soliton collisions in dispersion-managed wavelength-division-multiplexed systems

We show that collision-induced frequency shifts in wavelength-division-multiplexed (WDM) soliton transmission systems are strongly suppressed with increasing dispersion management. We predict new oscillations in the residual frequency shift response, owing to the relative motion induced by the dispersion map, and demonstrate a direct correlation between these oscillations and the modified soliton-collision dynamics. Simple analytical expressions for the oscillation minima are obtained, and implications for WDM soliton system design are discussed.