Search results for "Trigo"
showing 10 items of 253 documents
Ferromagnetic copper(II)–copper(II) interaction in a single chlorido and dicyanamido bridged mixed–valence copper(I/II) 2D polymer generated by in si…
2015
A mixed-valence 2-D Cu(I/II) complex, [{Cu(II)(dmen)(μ-Cl)(μ1,5-dca)}{Cu(I)(μ1,5-dca)}]n (1) (dmen = N,N-dimethylethylenediamine, dca = dicyanamide = [N(CN)2]−), has been synthesized by in situ partial reduction of Cu(II) to Cu(I) using benzoin (2-hydroxy-1,2-di(phenyl)ethanone) as reductant. Complex 1 was characterized by spectroscopic techniques, single crystal X-ray diffraction, and low temperature magnetic measurements. Structural investigation reveals that 1 represents a mixed-valence 2-D coordination polymer formed by parallel 1-D [Cu(II)(dmen)(Cl)Cu(I)(μ1,5-dca)2]n chains running along the b axis, where chloride bridges Cu(II) ions of adjacent polymers through long connections (2.840…
Geometrically diverse anions in anion–π interactions
2011
The role of different anion geometries in anion–π interactions is discussed. The chemistry described herein is different to the interaction of spherical cations with aromatics. The influence of different geometries makes selective anion recognition more complicated than respective cation sensing. The present structural study reveals attractive interactions between pentafluorophenyl units and geometrically diverse anions (linear, trigonal planar, tetrahedral and octahedral). Due to the electrostatic nature of anion–π interactions, the anion geometry seems to be irrelevant. The size of the anion controls the relative orientation of the anion and the π system (e.g. in compounds 1–3). The dimer…
Effect of Wheat Straw as a Cover Crop on the Chlorophyll, Seed, and Oilseed Yield of
2019
The effects of water stress on fenugreek crops are well documented. However, little is known about how these plants respond to water deficits under a soil-mulching system when the surface is protected. Therefore, the current research aims to demonstrate the possibility of reducing the impact of water stress and weed competition on the fenugreek crop through the use of wheat residues as a cover crop on the soil surface. A field experiment was carried out during the winter season (2016–2017) using a split-plot design arrangement with three replicates. The experiments included four levels of water deficit, which consisted of a 40% depletion treatment as a control plot, and 50%, 60%, and 70% de…
New and less known Orthoptera (Insecta) from the island of Socotra (Yemen)
2009
A list of nine species of Orthoptera collected on Socotra is reported. Three of them were previously unrecorded on the island (Trigonidium cicindeloides, Paratettix subpustulatus and Acrotylus insubricus) and one (Ochrilidia socotrae n.sp.) was undescribed. Further systematic notes on Glomeremus pileatus, G. mediopictus, Pyrgomorpha conica tereticornis, Acrotylus incarnatus and Sphingonotus insularis are included. The East African Acrotylus meruensis, previously considered synonym of A. incarnatus, is proposed as a valid species, distinct from the latter.
Contaminación de los cereales y los derivados de cereales por micotoxinas en Rumania
2017
Las micotoxinas son los contaminantes más frecuentes en el trigo y los productos a base de trigo. Las micotoxinas más importantes encontradas en trigo son principalmente las toxinas producidas por el género Fusarium, como deoxinivalenol (DON), zearalenona (ZEA), nivalenol, toxina HT-2 (HT-2), toxina T-2, y, recientemente estudiadas, las micotoxinas emergentes, en particular eniatinas (ENs) y beauvericina. La agricultura y en especial el cultivo de trigo son partes importantes de la economía rumana. A pesar de su alto potencial productor y consumidor, Rumania tiene registrados pocos datos relativos a la presencia de micotoxinas en los productos alimenticios a base de trigo. El objetivo de es…
Fractional-order theory of thermoelasticicty. I: Generalization of the Fourier equation
2018
The paper deals with the generalization of Fourier-type relations in the context of fractional-order calculus. The instantaneous temperature-flux equation of the Fourier-type diffusion is generalized, introducing a self-similar, fractal-type mass clustering at the micro scale. In this setting, the resulting conduction equation at the macro scale yields a Caputo's fractional derivative with order [0,1] of temperature gradient that generalizes the Fourier conduction equation. The order of the fractional-derivative has been related to the fractal assembly of the microstructure and some preliminary observations about the thermodynamical restrictions of the coefficients and the state functions r…
Oxovanadium(V) complexes with tripodal bisphenolate and monophenolate ligands: Syntheses, structures and catalytic activities
2019
Abstract The reactions between [VO(acac)2] (acac– = acetylacetonate) and the tripodal amino bisphenols 6,6′-(((2-morpholinoethyl)azanediyl)bis(methylene))bis(2,4-di-tert-butylphenol) (H2L1) and 6,6′-(((thiophen-2-ylmethyl)azanediyl)bis(methylene))bis(2,4-di-tert-butylphenol) (H2L2) as well as the tetradentate amino phenol 2,2′-((3,5-di-tert-butyl-2-hydroxybenzyl)azanediyl)bis(ethan-1-ol) (H3L3) afford the complexes [VO(L1)(OMe)] (1), [VO(L2)(acac)] (2) and [VO(L3)] (3), correspondingly. Complexes 1 and 3 can also be prepared using VOSO4·xH2O or [VO(OPr)3] as vanadium precursors. When [VO(acac)2] or VOSO4·xH2O is used, mononuclear oxovanadium(V) complexes are formed upon oxidation of the met…
Critical analysis of thermal inertia approaches for surface soil water content retrieval
2013
The “thermal inertia” method to retrieve surface soil water content maps on bare or sparsely-vegetated soils is analysed. The study area is a small experimental watershed, where optical and thermal images (in day and night time) and in situ data were simultaneously acquired. The sensitivity of thermal inertia to the phase difference between incoming radiation and soil temperature is demonstrated. Thus, to obtain an accurate value of the phase difference, the temporal distance between thermographs using a three-temperature approach is evaluated. We highlight when a cosine correction of the temperature needs to be applied, depending on whether the thermal inertia formulation includes two gene…
Complexes of titanium and zirconium containing a tridentate linked amido–cyclopentadienyl ligand with a soft donor group: synthesis, structure, and e…
1999
Abstract Group 4 metal complexes M(η5:η1-C5R4SiMe2NCH2CH2SMe)Cl2 (R=H, M=Ti; R=Me, M=Ti, Zr) containing the thioether-functionalized linked amido–cyclopentadienyl ligand were synthesized and characterized by 1H- and 13C-NMR spectroscopy, mass spectrometry, and elemental analysis. The crystal structures of the complexes Ti(η5:η1-C5H4SiMe2NCH2CH2SMe)Cl2 and Zr(η5:η1:η1-C5Me4SiMe2NCH2CH2SMe)Cl2 were determined by single-crystal X-ray diffraction studies. The titanium complex is a conventional three-legged piano-stool molecule without an intramolecular interaction between the sulfur donor group and the titanium center, whereas the zirconium complex adopts a trigonal bipyramidal structure, with …
Structural characterization of 2,2-di-n-butyl-4-methyl-1,3,2-dioxastannolane isolated from supercritical CO2 conditions
2009
The title compound has been isolated as single crystals from the synthesis of propylene carbonate from racemic 1,2-propanediol and carbon dioxide using n-Bu2SnO as a catalyst precursor. The X-ray crystallographic structure analysis revealed the self-assembly of di-n-butyltin(IV) 1,2-propanediolate units, linked together through long-distance Sn-O interactions leading to a one-dimensional polymeric architecture organized in a syndiotactic arrangement. The coordination geometry around the tin atoms can be described as an unusual faced-capped trigonal bipyramidal environment.