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Natural lifetimes were measured by time-resolved observation of laser-induced fluorescence. Free Ce, Ce+, and Ce++ particles were obtained in a laser-produced plasma. Lifetimes were measured for eight levels of singly ionized cerium, as well as for nine levels of doubly ionized cerium. The lifetime data were compared with previously published experimental and theoretical results.

The measured radiative lifetime of Rydberg states of neutral lead were compared with the values obtained by multichannel quantum defect theory (MQDT). The radiative lifetime of Rydberg state of Pb1 was calculated using laser abalation technique and time resolved laser spectroscopy. MQDT parameters were found by experimental estimation of energy levels and the theoretical lifetime was evaluated usi

Multichannel-quantum-defect theory (MQDT) analyses were carried out for the J=0, 1, and 2 even-parity Rydberg series level of Pb I. The MQDT wave functions of each level were obtained. With the wave functions and employing the experimental lifetimes and Landé (gJ) factors measured previously, the theoretical lifetimes of J=0,1, and 2 levels were evaluated as well as the theoretical gJ factors of J

Mid-IR polarization spectroscopy (IRPS) and laser-induced fluorescence were applied for detection of CH4 and ethane in 1 atm cold flows and flames. The dependence of IRPS and IRLIF signal of CH4 on different buffer gases, including He, Ar, N2, and CO2 were studied. Simultaneous measurements of IRPS and IRLIF signals allowed a direct comparison of the two techniques. IRPS was superior in detection

Technical developments for the detection of formaldehyde using laser-induced fluorescence were presented. A technique for simultaneous detection of formaldehyde and OH using one laser system was presented. The combined formaldehyde and OH technique was applied in laboratory flames and a small spark-ignition engine. The iodine measurement was performed in a cell using the second harmonic of the sin

This paper presents technical developments for the detection of formaldehyde (CH2O) using laser-induced fluorescence. The easily accessible third harmonic of the Nd:YAG laser at 355 nm was used for excitation of formaldehyde. In order to investigate potential background fluorescence, e.g., from large molecules such as polyaromatic hydrocarbons, special attention was paid to investigating the possi

Ammonia (NH3) is a sustainable fuel with excellent emission characteristics. Hence, it is important to develop diagnostic techniques for NH3 combustion. In this paper, femtosecond laser-induced plasma spectroscopy (FLIPS) was performed in premixed NH3∕air flames. The plasma emission spectra induced by the femtosecond laser in the flame and the chemiluminescence spectra of the flame itself were bot

Plastic litter is a growing environmental problem. Recently, microplastics and nanoplastics, produced during breakdown processes in nature, have been in focus. Although there is a growing knowledge concerning microplastic, little is still known about the effect of nanoplastics. We have showed that mechanical breakdown of high-density polyethylene (HDPE), followed by filtration through 0.8 µm filte

Lysine acetylation is a widespread posttranslational modification (PTM) in all kingdoms of live. A large number of proteins involved in most of biological pathways are targets of this PTM. The lysine acetylation is a reversible modification controlled by two main groups of enzymes, lysine acetyltransferases responsible for transferring the acetyl group of acetylCoA to the side chain of lysine resi

Introduction: The prognostic value of angina during exercise stress testing is controversial, possibly due to previous studies not differentiating typical from non-typical angina. We aimed to assess the prognostic value of typical angina alone, or in combination with ST depression, during exercise stress testing for predicting cardiovascular events. Methods: We conducted a prospective observationa

The goal of our research is the construction of efficient Jacobian-free preconditioners for high order Discontinuous Galerkin (DG) discretizations with implicit time integration. We are motivated by three-dimensional unsteady compressible flow applications, which often result in large stiff systems. Implicit time integrators overcome the impact upon restrictive CFL conditions on explicit ones but

A text may be seen as the result of input from the external world and human internal aspects on it. The paper shows how the same event — a submarine following a trawler — may give rise to different types (genres) of text, e.g., a report on the facts, an evaluation of the facts, a summary of the most important features against the background of previous events, or a mixture of some or all of these.

The health benefits of bean consumption are widely recognized and are largely attributed to the dietary fiber content. This study investigated and compared the effects of whole brown beans and an isolated bean dietary fiber fraction on the plasma lipid profile, atherosclerotic plaque amount, gut microbiota, and microbiota-dependent metabolites (cecal short-chain fatty acids (SCFAs) and plasma meth