Search results for " GENERAL"
showing 10 items of 33759 documents
An experimental and theoretical study of a heptacoordinated tungsten(VI) complex of a noninnocent phenylenediamine bis(phenolate) ligand
2018
Abstract [W(N2O2)(HN2O2)] (H4N2O2 = N,N′-bis(3,5-di-tert-butyl-2-hydroxyphenyl)-1,2-phenylenediamine) with a noninnocent ligand was formed by reaction of the alkoxide precursor [W(eg)3] (eg = the 1,2-ethanediolate dianion) with two equivalents of ligand. The phenol groups on one of the ligands are completely deprotonated and the ligand coordinates in a tetradentate fashion, whereas the other ligand is tridentate with one phenol having an intact OH group. The molecular structure, magnetic measurements, EPR spectroscopy, and density functional theory calculations indicate that the complex is a stable radical with the odd electron situated on the tridentate amidophenoxide ligand. The formal ox…
On the mechanism of imine elimination from Fischer tungsten carbene complexes
2016
(Aminoferrocenyl)(ferrocenyl)carbene(pentacarbonyl)tungsten(0) (CO)5W=C(NHFc)Fc (W(CO)5(E-2)) is synthesized by nucleophilic substitution of the ethoxy group of (CO)5W=C(OEt)Fc (M(CO)5(1Et)) by ferrocenyl amide Fc-NH– (Fc = ferrocenyl). W(CO)5(E-2) thermally and photochemically eliminates bulky E-1,2-diferrocenylimine (E-3) via a formal 1,2-H shift from the N to the carbene C atom. Kinetic and mechanistic studies to the formation of imine E-3 are performed by NMR, IR and UV–vis spectroscopy and liquid injection field desorption ionization (LIFDI) mass spectrometry as well as by trapping experiments for low-coordinate tungsten complexes with triphenylphosphane. W(CO)5(E-2) decays thermally i…
An evaluation of cool season turfgrassess in order to identify the species and varieties most suitable for the Mediterranean environment
2004
The cultivars of cool season Graminae species diffusely used to establish turfgrasses, are grown in northern areas of Europe. The aim of the research described in this paper was to identify the turfgrass species and cultivars most suitable for the Mediterranean environment. The trial was carried out in 1999 and 2000 at the experimental farm “Parco d’Orleans” belonging to the Department A.C.E.P. of University of Palermo. During the trial sixty different cultivars of cool season turf species were compared – 20 cultivars of Festuca arundinacea Schreb., 20 cultivars of Poa pratensis L., and 20 cultivars of Lulium perenne L. The main biometric and qualitative parameters examined were ground cove…
Patterning of supported gold monolayers via chemical lift-off lithography
2017
The supported monolayer of Au that accompanies alkanethiolate molecules removed by polymer stamps during chemical lift-off lithography is a scarcely studied hybrid material. We show that these Au–alkanethiolate layers on poly(dimethylsiloxane) (PDMS) are transparent, functional, hybrid interfaces that can be patterned over nanometer, micrometer, and millimeter length scales. Unlike other ultrathin Au films and nanoparticles, lifted-off Au–alkanethiolate thin films lack a measurable optical signature. We therefore devised fabrication, characterization, and simulation strategies by which to interrogate the nanoscale structure, chemical functionality, stoichiometry, and spectral signature of t…
Strictly correlated electrons approach to excitation energies of dissociating molecules
2019
In this work we consider a numerically solvable model of a two-electron diatomic molecule to study a recently proposed approximation based on the density functional theory of so-called strictly correlated electrons (SCE). We map out the full two-particle wave function for a wide range of bond distances and interaction strengths and obtain analytic results for the two-particle states and eigenenergies in various limits of strong and weak interactions, and in the limit of large bond distance. We then study the so-called Hartree-exchange-correlation (Hxc) kernel of time-dependent density functional theory which is a key ingredient in calculating excitation energies. We study an approximation b…
A class of multivariate type I generalized logistic distributions
2010
The logistic distribution has found important applications in many different fields and several different forms of generalizations have been proposed in the literature. However it seems, with a few exceptions, that there are not in the literature forms of multivariate generalized logistic distributions. In this paper we focus on the type I generalized logistic distribution and, based on a procedure of multivariate transformation of multivariate exponential distributions, we introduce a class of multivariate type I generalized logistic distributions. We provide some examples of bivariate and multivariate distributions of this class.
Musculoskeletal disorders and disability among forest industry workers in lower and higher sickness absence groups: a case-control study
2019
Background: Musculoskeletal wellbeing and disorders and explanatory factors were investigated among forest industry employees. Methods: A new positive approach to maintenance of working ability focuses on being present at work. 140 individuals with low sickness absence (≤1.5% in hours during the past 6.5 years) and 140 controls with higher sickness absence (>1.5%), randomly selected from the source population (n = 636) in workplace clusters (n = 5), were studied. Questionnaire data on functioning, musculoskeletal disorders (MSD) and disability, work ability and wellbeing were collected (response rate 65%) during December 2012–January 2013. 183 employees (mean age 48.5; females 32%) particip…
The associations of quantitative/qualitative job insecurity and well-being: The role of self-esteem.
2019
Job insecurity is recognized as one of the most prominent job stressors for employees. Despite decades of research, the concurrent examination of both quantitative (i.e. perceived threat of job loss) and qualitative (i.e., perceived threat of losing some job features) job insecurity and the analysis of their different relationships with well-being at work have received relatively scarce attention. This study examined a moderated mediation model of the relationship between quantitative job insecurity and well-being at work. In doing so, the focus was on the mediating effects of qualitative job insecurity and the moderating effects of self-esteem in the abovementioned relationships. Drawing f…
Analyses of udder health in Valle del Belice dairy sheep using SCC
2005
Intramammary infections (IMI) are a complex of inflammatory diseases of the mammary gland. Mastitis is one of the most frequent IMI affecting small dairy ruminants. Direct selection against clinical mastitis is difficult because mastitis in not widely recorded; therefore, somatic cell count (SCC) is promoted as selection criterion for mastitis resistance. A dataset containing 2,457 first- lactation Valle del Belice ewes from 14 flocks recorded from 1998 to 2003 was analysed. In total 116 sires with at least four daughters with a record were included in the pedigree file. Test-day IMI events were coded as a binary trait using a SCC cut-off value of 750,000 cells/ml. Analyses of risk factors …
Profiles of Nature Exposure and Outdoor Activities Associated With Occupational Well-Being Among Employees.
2018
This research addresses the profiles of nature exposure and outdoor activities in nature among Finnish employees (N = 783). The profiles were formed on the bases of nature exposure at work and the frequency and type of outdoor activities in nature engaged in during leisure time. The profiles were investigated in relation to work engagement and burnout. The latent profile analysis identified a five-class solution as the best model: High exposure (8%), Versatile exposure (22%), Unilateral exposure (38%), Average exposure (13%), and Low exposure (19%). An Analysis of Covariance (ANCOVA) was conducted for each well-being outcome in order to evaluate how the identified profiles related to occupa…