Search results for " couple"
showing 10 items of 374 documents
Stable Copper Isotopes: A Novel Tool to Trace Copper Behavior in Hydromorphic Soils
2010
Copper is an essential micronutrient for all organisms but may also be a pollutant. We studied the natural abundance of stable Cu isotope ratios in four soils to test whether δ 65 Cu values can be used as a tracer for biogeochemical processes in hydromorphic soils. Two of the soils were affected by stagnant water and the other two by groundwater. We determined standard soil properties and Cu partitioning into seven fractions of a sequential extraction. Copper stable isotope ratios were measured in total soil digests with multicollector inductively coupled plasma mass spectrometry. Copper concentrations in the study soils were low to average (5-34 mg kg -1 ). The variation in Cu isotope rati…
A computational study of some electric and magnetic properties of gaseous BF3 and BCl3
2005
We present the results of an extended computational study of the electric and magnetic properties connected to Cotton-Mouton birefringences, on the trifluoro- and trichloroborides in the gas phase. The electric dipole polarizabilities, magnetizabilities, quadrupole moments, and higher-order hypersusceptibilities—expressed as quadratic and cubic frequency-dependent response functions—are computed within Hartree-Fock, density-functional, and coupled-cluster response theories employing singly and doubly augmented correlation-consistent basis sets and London orbitals in the magnetic property calculations. The results, which illustrate the capability of time-dependent density-functional theory f…
Relativistic coupled cluster calculations of the electronic structure of KrH+, XeH+ and RnH+
2012
Potential energy curves of NgH+ cations (Ng = Kr, Xe, Rn) were obtained by using four-component relativistic CCSD(T) coupled cluster calculations. Dissociation energies, equilibrium bond lengths, electronic properties, such as dipole moments and electric field gradients at the nuclei, and the related spectroscopic parameters of the electronic ground state have been determined. The results obtained for KrH+ and XeH+ are in good agreement with available experimental data, while those for RnH+ have been determined for the first time at this level of theory.
Forensic investigation of brick stones using instrumental neutron activation analysis (INAA), laser ablation-inductively coupled plasma-mass spectrom…
2009
Abstract Brick stones collected from different production facilities were studied for their elemental compositions under forensic aspects using laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS), instrumental neutron activation analysis (INAA) and X-ray fluorescence analysis (XRF). The aim of these examinations was to assess the potential of these methods in forensic comparison analyses of brick stones. The accuracy of the analysis methods was evaluated using NIST standard reference materials (679, 98b and 97b). In order to compare the stones to each other, multivariate data analysis was used. The evaluation of the INAA results (based on the concentrations of V, Na, K, …
Direct determination of halogens in powdered geological and environmental samples using isotope dilution laser ablation ICP-MS
2005
Abstract Laser ablation inductively coupled plasma isotope dilution mass spectrometry (LA-ICP-IDMS) with a special laser ablation system for bulk analyses (LINA-Spark™-Atomiser) was applied for direct determinations of chlorine, bromine, and iodine in rock and sediment samples. Special attention was focused on possible inter-halogen fractionations and analyte/spike isotope fractionations by using LA-ICP-MS and LA-ICP-IDMS, respectively. A variation of Br/Cl and I/Cl element intensity ratios by a factor of 1.3–3 was observed when changing the nebulizer gas flow rate in the range of 0.84–1.0 L min−1 and the laser power density in the range of 2–10 GW cm−2, respectively. When using an internal…
Cobalt Electrolyte/Dye Interactions in Dye-Sensitized Solar Cells: A Combined Computational and Experimental Study
2012
We report a combined experimental and computational investigation to understand the nature of the interactions between cobalt redox mediators and TiO2 surfaces sensitized by :ruthenium and organic dyes, and their impact on. the performance of the corresponding dye-sensitized solar cells (DSSCs). We : focus: on different ruthenium dyes and fully organic dyes, to understand the dramatic loss of efficiency observed for the prototype Ru(II) N719 dye in conjunction with :Cobalt: electrolytes. Both N719- and Z907-based DSSCs showed an increased lifetime in iodine-based electrolyte compared to the cobalt-based redox-shuttle; While the organic D21L6 and D25L6 cycles endowed.With long alkoxy chains,…
The role of sexting in couple wellbeing for Italian women during the second wave of the COVID-19 pandemic
2023
The social isolation due to the COVID-19 pandemic had an impact on the sexuality and quality of life of people around the world. A particularly negative effect was detected on women’s sexual health. As a consequence, many women began to use social media not only to stay in touch with their social networks, but as a way of maintaining sexual contact. The main aim of this research is to observe the positive effects of sexting in women’s wellbeing as a strategy to manage the negative effects of a condition of forced isolation. We collected all our data between November 2020 and March 2021 during a period of strict restrictions in Italy due to the second wave of the COVID-19 pandemic. In Study …
Ultrasound-assisted sequential extraction method for the evaluation of mobility of toxic elements in contaminated soils
2005
A method for the fast sequential extraction of toxic elements in contaminated soil samples using an ultrasonic water bath, followed by determination with inductively coupled plasma optical emission spectrometry (ICP-OES), was developed and compared with other methods introduced in the literature. The five-step sequential extraction (Tessier scheme) was shortened using ultrasound-assisted sequential extraction (UASE). The optimization of the five-step sequential extraction was based on the analysis of SRM 2710 using Tessiers’s method as a reference. Several extracting solutions with different sonication times and temperatures were tested in the optimization procedure. Concentrations of arsen…
High-resolution analysis of trace elements in crustose coralline algae from the North Atlantic and North Pacific by laser ablation ICP-MS
2011
We have investigated the trace elemental composition in the skeleta of two specimens of attached-living coralline algae of the species Clathromorphum compactum from the North Atlantic (Newfoundland) and Clathromorphum nereostratum from the North Pacific/Bering Sea region (Amchitka Island, Aleutians). Samples were analyzed using Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) yielding for the first time continuous individual trace elemental records of up to 69 years in length. The resulting algal Mg/Ca, Sr/Ca, U/Ca, and Ba/Ca ratios are reproducible within individual sample specimens. Algal Mg/Ca ratios were additionally validated by electron microprobe analyses (Amch…
Assessment for the mean value total dressing method: Comparison with coupled cluster including triples methods for BF, NO+, CN+, C2, BeO, NH3, CH2, H…
1997
Limited previous experience with the mean value total dressing (MVTD) method had shown that MVTD energies for closed shell systems are generally better than CCSD(T) ones compared to FCI. The method, previously published as total dressing 2′(td-2′), is based on the single reference intermediate Hamiltonian theory. It is not a CC method but deals in a great part with the same physical effects that CC methods that incorporate amplitudes of triples such as CCSDT or its CCSDT-1n approaches. A number of test calculations comparing to diverse CC methods, as well as FCI and experiment when available, have been performed. The tests concern equilibrium energies in NH3 and CH2, equilibrium energies an…