Search results for "FUNCTIONAL"

The characterization of molecular alkaly metal azides

2006

Matrix isolation infrared (IR) studies have been carried out on the vaporisation of the alkali-metal azides MN(3) (M = Na, K, Rb and Cs). The results show that under high vacuum conditions, molecular KN(3), RbN(3) and CsN(3) are present as stable high-temperature vapour species, together with variable amounts of nitrogen gas and the corresponding metal atoms. The characterisation of these molecular azides is supported by ab initio molecular orbital calculations and density functional theory (DFT) calculations, and for CsN(3) in particular, by the detection of the isotopomers CS((14)N(15)N(14)N) and Cs((15)N(14)N(14)N). The IR spectra are assigned to a "side-on" (C(2v)) structure by comparis…

Stepwise formation of a pentanuclear Ni4Cu heterometallic complex exhibiting a vertex-sharing defective double-cubane core and diphenoxo- and phenoxo…

2013

Sequential reaction of a N5O3 octadentate tripodal ligand with Ni(2+) and subsequently with Cu(2+) and azide ligand afforded the first example of a heterobridged (phenoxo/μ(1,1)-azido) pentanuclear heterometallic (Ni4Cu) compound, which exhibits a centrosymmetric vertex-sharing defective double-cubane structure. The study of the magnetic properties reveals that the compound shows ferromagnetic interaction interactions, leading to an S = 9/2 spin ground state. Density functional theory calculations on the X-ray structure and model compounds predict ferromagnetic interactions through the magnetic exchange pathways involving each couple of metal ions.

Generic Method for Modular Surface Modification of Cellulosic Materials in Aqueous Medium by Sequential Click-Reaction and Adsorption

2012

A generic approach for heterogeneous surface modification of cellulosic materials in aqueous medium, applicable for a wide range of functionalizations, is presented. In the first step, carboxymethyl cellulose (CMC) modified with azide or alkyne functionality, was adsorbed on a cellulosic substrate, thus, providing reactive sites for azide–alkyne cycloaddition click reactions. In the second step, functional units with complementary click units were reacted on the cellulose surface, coated by the click-modified CMC. Selected model functionalizations on diverse cellulosic substrates are shown to demonstrate the generality of the approach. The concept by sequentially combining the robust physic…

A Theoretical Study of the Relationship between the Electrophilicity ω Index and Hammett Constant σp in [3+2] Cycloaddition Reactions of Aryl Azide/A…

2016

The relationship between the electrophilicity ω index and the Hammett constant σp has been studied for the [2+3] cycloaddition reactions of a series of para-substituted phenyl azides towards para-substituted phenyl alkynes. The electrophilicity ω index—a reactivity density functional theory (DFT) descriptor evaluated at the ground state of the molecules—shows a good linear relationship with the Hammett substituent constants σp. The theoretical scale of reactivity correctly explains the electrophilic activation/deactivation effects promoted by electron-withdrawing and electron-releasing substituents in both azide and alkyne components.

Application of PGPB Combined with Variable N Doses Affects Growth, Yield-Related Traits, N-Fertilizer Efficiency and Nutritional Status of Lettuce Gr…

2022

Nitrogen (N) fertilization is a crucial agricultural practice for boosting production traits in vegetables. However, N synthetic fertilizers—commonly adopted by farmers—have several counterproductive effects on the environment and on humans. The research was performed to assess the combined influence of plant growth promoting bacteria (PGPB) (Azospirillum brasilense DSM 1690, A. brasilense DSM 2298 and Pseudomonas sp. DSM 25356) and various N fertilization doses (0, 30, 60 or 120 kg ha−1) on growth, yield, quality and nitrogen indices of lettuce in protected cultivation. Plant height, root collar diameter, number of leaves and fresh weight were enhanced by A. brasilense DS…

Observation of an Excited $B^{\pm}_c$ Meson State with the ATLAS Detector

2014

A search for excited states of the B±c meson is performed using 4.9 fb-1 of 7 TeV and 19.2 fb-1 of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic transition to the ground state, with the latter detected in the decay B±c→J/ψπ±. The state appears in the m(Bc±π+π-)-m(Bc±)-2m(π±) mass difference distribution with a significance of 5.2 standard deviations. The mass of the observed state is 6842±4±5 MeV, where the first error is statistical and the second is systematic. The mass and decay of this state are consistent with expectations for the second S-wave state of the B±c meson, B±c(2S).

Crystal and molecular structure studies of (Z)-N-methyl-C-4-substituted phenyl nitrones by XRD, DFT, FTIR and NMR methods

2017

Abstract (Z)-N-methyl-C-4-substituted phenyl nitrones –O+N(Me)=C(H)R (Z-2a R = 4-ClC6H4, Z-2b R = 4-NO2C6H4, Z-2c R = 4-CH3OC6H4) were synthesized and characterized by elemental analyses, FTIR, 1H, 13C and DEPT-135 NMR spectroscopy and also by single crystal X-ray diffraction (in the case of Z-2a and Z-2b). The geometries of the nitrone molecules Z-2a, Z-2b and Z-2c and their E-isomers; (E)-N-methyl-C-4-chlorophenyl nitrone E-2a, (E)-N-methyl-C-4-nitrophenyl nitrone E-2b and (E)-N-methyl-C-4-methoxyphenyl nitrone E-2c were optimized using density functional theory (DFT) at the B3LYP/6-311++G(d,p) level of theory. The theoretical vibrational frequencies obtained by DFT calculations are in go…

INSIGHTS WITHIN APR PROCESS USING VDW-DF FUNCTIONAL

2014

Computational modelling of boron nitride nanostructures based on density-functional tight-binding

2014

Boorinitridin (BN) nanorakenteet ovat sekä rakenteellisesti että lujuusominaisuuksiensa puolesta hyvin samankaltaisia vastaavien hiilirakenteiden kanssa. Suurimpana erona on BN:n sähköinen eristävyys kun taas hiilirakenteet ovat johteita tai puolijohteita. BN onkin hyvin lupaava nanomateriaali ja sille on odotettavissa sovelluksia muun muassa muiden nanorakenteiden suojaajana ja komposiittimateriaalien nanokudosaineena. BN:n nanorakenteiden ominaisuuksia tutkitaan laskennallisesti yleensä joko tiheysfunktionaaliteorialla (DFT) tai tiukan sidoksen (TB) malleilla. Ensin mainittu on tarkka mutta laskennallisesti vaativa, kun taas jälkimmäinen on laskennallisesti kevyt mutta epätarkka. Tässä ty…

ANCORA SULLA PORTATA DELLA NOZIONE DI “CESSAZIONE DELL’ATTIVITÀ D’AZIENDA” A PROPOSITO DEL LICENZIAMENTO DELLA LAVORATRICE MADRE NEL CORSO DI UNA PRO…

2018

Con la sentenza annotata la Corte di Cassazione torna a pronunciarsi sulla corretta interpretazione di una delle eccezioni al divieto di licenziamento sancito dall’art. 54 D. Lgs. n. 151/2001, chiarendo che nell’ipotesi di cessazione dell’attività d’azienda non può intendersi ricompresa anche la cessazione dell’attività di un singolo reparto, seppur dotato di autonomia funzionale. Nel ripercorrere il ragionamento seguito dai giudici, la nota richiama alcuni importanti principi in materia di licenziamento delle lavoratrici madri nel periodo protetto. The judgment in question makes a remark about the meaning of the exception to the prohibition of dismissal, according to the article 54 D. Lgs.…