Miracle-dz/UniFAR-FTUs huggingface dataset:
Topological studies of the charge density of some group 2 metallocenes M(η5-C5H5)2 (M = Mg or Ca)

Ab initio quantum chemical calculations using both the Hartree–Fock and the B3LYP density functional theory methods have been performed for the group 2 metallocenes M (η5-C5-C5H5)2 (M = Mg or Ca). The topology of the calculated charge density (ρ) and its Laplacian have been analysed using a new critical point search algorithm in order to understand why Mg(η5-C5-H5)2 is linear while Ca(η-C5H5)2 is bent. The Laplacian of the core of the Ca atom in Ca(η5-C5H5)2 is perturbed by the polarizing field of the cyclopentadienyl ligands and the bent geometry is a consequence of the interactions between the distorted core and the ligand atoms. In the case of Mg(η5-C5H5)2, charge concentration maxima in the Mg core occur along the vectors connecting the metal to the centroids of the cyclopentadienyl ligands irrespective of whether or not the molecule is linear, and the preferred geometry is linear as expected. The results of these calculations demonstrate that the geometries of the group 2 metallocenes can be understo.
Effects of Spent Cooling and Swirler Angle on a 9-Point Swirl-Venturi Injector

This paper presents multipoint Lean-Direct-Injection (LDI) emissions results for flame tube combustion tests at an inlet pressure of 1034 kPa and inlet temperatures between 835 and 865 K; these are the combustor inlet conditions that the High Speed Research (HSR) program used for supersonic cruise. It focuses on one class of LDI geometry, 9-point swirl-venturi LDI (SV-LDI). Two parameters are compared in this paper: the use of dome cooling air and the swirler blade angle. Dome cooling air is called "spent cooling" and is at combustor inlet conditions. Three cooling variations are studied: cooling at the venturi throat, cooling at the dome face, and no cooling at all. Two swirler blade angles are studied: 45deg and 60deg. The HSR 9-point SV-LDI emissions are also compared to a similar 9-point SV-LDI design which was used in the later ultra-efficient engine technology (UEET) program. The HSR and UEET designs cannot be compared directly due to different UEET combustor conditions. Therefore, this paper uses previously published UEET correlation equations to make comparisons. Results show that using a 45deg swirler produces lower NOx emissions than using a 60deg swirler. This is consistent with the later UEET results. The effects of spent cooling depend on swirler angle, spent cooling location, and the test conditions. For the configuration with 45deg swirlers, spent cooling delivers lower NOx emissions when it is injected at the throat. For the 60deg swirler, spent cooling does not have much effect on NOx emissions. These results might be caused by the location and the intensity of the flame recirculation zone.
Pressure Effect on the 2NaH+MgB2 Hydrogen Absorption Reaction

The hydrogen absorption mechanism of the 2NaH + MgB2 system has been investigated in detail. Depending on the applied hydrogen pressure, different intermediate phases are observed. In the case of absorption measurements performed under 50 bar of hydrogen pressure, NaBH4 is found not to be formed directly. Instead, first an unknown phase is formed, followed upon further heating by the formation of NaMgH3 and a NaH−NaBH4 molten salt mixture; only at the end after heating to 380 °C do the reflections of the crystalline NaBH4 appear. In contrast, measurements performed at lower hydrogen pressure (5 bar of H2), but under the same temperature conditions, demonstrate that the synthesis of NaBH4 is possible without occurrence of the unknown phase and of NaMgH3. This indicates that the reaction path can be tuned by the applied hydrogen pressure. The formation of a NaH−NaBH4 molten salt mixture is observed also for the measurement performed under 5 bar of hydrogen pressure with the formation of free Mg. However, un.
Structure of 1-(Thiophen-2-ylmethyl)-2-(thiophen-2-yl)-1H-benzimidazole

The title compound, C16H12N2S2, crystallizes in the monoclinic space group P21/n with Z = 4, a = 8.950 (5) A, b = 9.141 (5) A, c = 17.429 (5) A and b = 93.638 (5)°. The benzimidazole ring is essentially planar. The crystal structure is stabilized by intermolecular C---H . N and C---H . p contacts.
NUMERICAL SIMULATIONS OF TURBULENT REACTIVE FLOWS USING A HYBRID LES / PDF METHODOLOGY

Time-resolved numerical simulations of fluid flows, such as Large Eddy Simulations (LES), have the capability of simulating the unsteady dynamic of large scale energetic structures. However, they are known to be intrinsically sensitive to inflow conditions the modelling of which may become a crucial ingredient of the computational model. The present work reports LES of both reactive and non reactive turbulent channel flows of methane/air mixtures. The flow configuration and associated conditions correspond to those associated with a reference experimental database that has been obtained at the french aerospace Laboratory of Onera. The focus of our study is placed on the influence of synthetic inlet turbulence in this experimental configuration, and the principal aim is to investigate the sensitivity of the flow dynamics and mixing to inflow conditions. This sensitivity is illustrated for four distinct turbulent inflows obtained from white noise, digital filters, the random flow generator (RFG), and synthetic eddy model (SEM). Finally the results obtained for reactive flow conditions clearly emphasize the influence of the retained model on the chemical reaction rate statistics. This highlights confirms how relevant are the developments devoted to synthetic turbulence for the computational investigation of turbulent combustion.
Modelling water chemistry for a major Scottish river from catchment attributes

1. The prediction of water quality is increasingly required in river catchment management, but methods are still developmental. We therefore derived empirical models to predict the concentrations of base cations, H+ and alkalinity at any point in a complex Scottish river system, and under diverse discharge conditions. Input data were readily available from geological and topographic maps, whole rock composition data and catchment land use inventories in geographical information systems (GIS). 2. A key and novel feature of the model was prediction using geological data for the riparian zone within 50 m of the river. The discharge contributions that passed through soil derived from each parent rock were estimated and used as weightings in predicting final run-off quality. 3. Typical equations for upland catchments for mean, maximum or minimum river water Ca concentration, [Ca], were of the form [Ca] = a + b √{Carz}, where {Carz} denotes flow routing-weighted rock CaO concentration of the riparian zone rock types present. These equations were significant at P < 0·0001. Similar approaches were applicable to alkalinity and to other base cations. 4. Predictions of [Ca] in catchments with mixed land use were improved by including model terms for catchment riparian zone cover of agriculturally improved (intensified) grassland and arable land. These results indicated anthropogenic effects on base cation flux that would not be represented by geological data alone. 5. Similarly, concentrations of Na, Mg and K were correlated with Cl concentration in the river water, primarily as a consequence of marine-derived Cl. Including distance from the east coast as a predictive variable in place of [Cl] obviated the need for direct [Cl] measurement in model operation. 6. We advocate further work to assess whether similar models can be developed and applied in other geographical locations, where features such as land use, geology and sea salt inputs will all vary.
Interaction of Copper(II) with Ditopic Pyridyl-β-diketone Ligands: Dimeric, Framework, and Metallogel Structures

The interaction of Cu(II) with three β-diketone ligands of type R1C(O)CH2C(O)R2 (where R1 = 2-, 3-, or 4-pyridyl and R2 = C6H5, respectively), HL1−HL3, along with the X-ray structures and the pKa values of each ligand, are reported. HL1 yields a dimeric complex of type [Cu(L1)2]2. In this structure, two deprotonated HL1 ligands coordinate in a trans planar fashion around each Cu(II) center, one oxygen from each CuL2 unit bridges to an axial site of the second complex unit such that both Cu(II) centers attain equivalent five-coordinate square pyramidal geometries. The two-substituted pyridyl groups in this complex do not coordinate, perhaps reflecting steric factors associated with the closeness of the pyridyl nitrogen to the attached (conjugated) β-diketonato backbone of each ligand. The remaining two Cu(II) species, derived from HL2 and HL3, are both coordination polymers of type [Cu(L)2]n in which the terminal pyridine group of each ligand is intermolecularly linked to an adjacent copper center to gener.
Mapeamento do saldo de radiação com imagens Landsat 5 e modelo de elevação digital

Net radiation is an important component of the surface energy balance in studies of evapotranspiration of irrigated crops and in evaporation of hydrological basins. The objective of this research was to determine the surface radiation balance, by using multispectral imagery of the Thematic Mapper (Landsat 5 satellite). In this study the SEBAL (Surface Energy Balance Algorithm for Land) and DEM (Digital Elevation Model) were used in order to correct the albedo and vegetation indices under the influence of the slope aspects were used for each study area. TM (Thematic Mapper) imageries were used for two different dates (December 4, 2000 and October 4, 2001). The calculations were accomplished with and without use of the DEM. The land surface temperature and albedo values with DEM were larger than without DEM in both years, for two selected areas. Results also show that for obtaining net radiation based on imagery of the TM - Landsat 5 the topographical effects of the study area must be considered.
Crystal-Chemical Factors Responsible for the Distribution of Octahedral Cations Over trans- and cis-Sites in Dioctahedral 2:1 Layer Silicates

Crystal chemical analysis of various dioctahedral 2:1 phyllosilicates consisting of trans-vacant (tv) and cis-vacant (cv) layers and interstratified cv and tv layers shows that there is compositional control over the distribution of octahedral cations over trans and cis sites. Fe3+ and Mg-rich dioctahedral micas (celadonite, glauconite, leucophyllite and most phengite) occur only as tv varieties. Similarly, the occurrence of tv illites and tv illite fundamental particles in illite-smectite (I-S) does not depend significantly on the cation composition of the 2:1 layers. In contrast, compositional restrictions exist to control the occurrence of pure cv1M illite, which can form only as Fe- and Mg-poor varieties. Similarly, proportions of cv and tv layers in illite fundamental particles depend on the amount of Al in octahedral and tetrahedral sheets of the 2:1 layers.Simulations of atomic coordinates and interatomic distances for periodic tv1M and cv1M illite structures allow us to reveal the main structural factors that favor the formation of cv layers in illite and I-S. It is shown that in contrast to the tv1M structure, interlayer K in cv1M illite has an environment which is similar to that in 2M1 muscovite. This similarity along with a high octahedral and tetrahedral Al content probably provides stability for cv1M illite in low-temperature natural environments. Because of structural control, the occurrence of monomineral cv1M illite, its association with tv 1M illite, and interstratified cv-tv illite fundamental particles is confined by certain physical and chemical conditions. These varieties are most often formed by hydrothermal activity of different origin. The initial material for their formation should be Al-rich and the hydrothermal fluids should be Mg- and Fe-poor. They occur mostly around ore deposits, in bentonites and in sandstone sedimentary rocks.The factors governing the formation of tv and cv layers in dioctahedral smectite are probably related to the layer composition and local order-disorder in the distribution of isomorphous octahedral cations, because there is no influence from fixed interlayer cations. In particular, the occurrence of Mg-OH-Mg cation arrangements is more favorable for the formation of cv montmorillonite layers.
Vibrational analysis of HOCl up to 98% of the dissociation energy with a Fermi resonance Hamiltonian

We have analyzed the vibrational energies and wave functions of HOCl obtained from previous ab initio calculations [J. Chem. Phys. 109, 2662 (1998); 109, 10273 (1998)]. Up to approximately 13 000 cm−1, the normal modes are nearly decoupled, so that the analysis is straightforward with a Dunham model. In contrast, above 13 000 cm−1 the Dunham model is no longer valid for the levels with no quanta in the OH stretch (v1=0). In addition to v1, these levels can only be assigned a so-called polyad quantum number P=2v2+v3, where 2 and 3 denote, respectively, the bending and OCl stretching normal modes. In contrast, the levels with v1⩾2 remain assignable with three vi quantum numbers up to the dissociation (D0=19 290 cm−1). The interaction between the bending and the OCl stretch (ω2≅2ω3) is well described with a simple, fitted Fermi resonance Hamiltonian. The energies and wave functions of this model Hamiltonian are compared with those obtained from ab initio calculations, which in turn enables the assignment of .
Organic foods: consumer attitudes and use

Resultats d'une enquete aupres des consommateurs californiens quant a leurs habitudes alimentaires: type de produits consommes, les raisons, les additifs, la perception du changement de qualite avec le temps. Etude en fonction des couches socio-economiques et demographiques
Diffusion of H2O and I− in expandable mica and montmorillonite gels: Contribution of bound H2O

Self-diffusion coefficients of H2O molecules in water-rich gels of Na-rich expandable mica synthesized using natural talc were measured by pulsed-gradient spin-echo 1H nuclear magnetic resonance (NMR), and the dependence on mica fraction (0.00–43.8 wt.%) and temperature (30.0–60.9°C) was examined. On the basis of the NMR results, the self-diffusion coefficient of H2O, Dwater, in the gel can be expressed by ln(Dwater/D0water) = 1.64[exp( −0.0588w) - 1], where D0water is the self-diffusivity of bulk water at temperature and w is the weight fraction of the mica (wt.%). The activation energy of H2O diffusivity in mica gel is nearly equal to that in bulk water. These findings indicate that the normalized diffusivity, Dwater/D0water, is independent of temperature. The diffusivity of I−, Diodine, in the gels was examined by X-ray computed tomography (CT) at 22°C, and the influence of the mica fraction (0.00–24.8 wt.%) was studied to determine the contribution of bound H2O. The X-ray CT results show that the normalized I− diffusivity, Diodine/D0iodine, obeys the above-mentioned phenomenological curve where D0iodine is the I− diffusivity in bulk water. I− is non-sorbing, and thus its diffusion is restricted only by the geometrical complexity of the pore structure of gels. Therefore, the effect of bound H2O molecules on average H2O diffusivity is negligible for w <24.8 wt. %. Diffusivity is governed by free or unbound H2O molecules diffusing in the geometrically complex and tortuous pore structure of mica-mineral grains. This is a result of the large population of unbound H2O far from the grain surface compared to the small population of bound H2O near the grain surface. The diffusion of I− ions in montmorillonite gels was examined by X-ray CT for w <16.7 wt. % montmorillonite. The normalized iodine diffusivity, (Diodine/D0iodine) obtained is in reasonably close agreement with the literature data for the normalized diffusivity of H2O and is similar to the master curve of expandable mica. Therefore, bound H2O molecules near negatively charged clay surfaces do not play a major role in the H2O diffusivity for water-rich montmorillonite gels.
HLB value, an important parameter for the development of essential oil phytopharmaceuticals

Essential oils are used primarily as natural preservatives, flavourants and fragrances in cosmetic products. Several pharmacopeias possess monographs of plants which are good sources of essential oils, such as Brazilian Pharmacopeia, including Illicium verum Hook. f. , Schisandraceae and Rosmarinus offi cinalis. Since determination of Hydrophile-Lipophile Balance (HLB) value of essential oils appears as a critical step for development of emulsions and other semi-solid formulations, evaluation of required HLB values for I. verum and R. offi cinalis essential oils is the aim of this study. They were obtained by hydrodistillation and several emulsions were prepared by changing emulsifiers. The couple sorbitan oleate/polysorbate 20 provided best emulsions and was used at different ratios, at a total blend concentration of 5% w/w. The lowest mean droplet diameters for R. offi cinalis and I. verum emulsions were obtained at HLB 16.5 (97.12 nm) and 16.7 (246.6 nm), respectively. Moreover, emulsions with R. offi cinalis were finer and presented some bluish reflection, characteristic of nanoemulsions. The lowest turbidity value for R. offi cinalis emulsion was also obtained at HLB 16.5 (0.33). Thus, the present study describes for the first time HLB values for R. offi cinalis (16.5) and I. verum (16.7) essential oils, contributing to their physicochemical characterization and technology development of phytopharmaceuticals.
The δ-Opioid Receptor Agonist SNC80 [(+)-4-[α(R)-α-[(2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl]-(3-methoxybenzyl)-N,N-diethylbenzamide] Synergistically Enhances the Locomotor-Activating Effects of Some Psychomotor Stimulants, but Not Direct Dopamine Agonists, in Rats

The nonpeptidic δ-opioid agonist SNC80 [(+)-4-[α(R)-α-[(2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl]-(3-methoxybenzyl)-N,N-diethylbenzamide] produces many stimulant-like behavioral effects in rodents and monkeys, such as locomotor stimulation, generalization to cocaine in discrimination procedures, and antiparkinsonian effects. Tolerance to the locomotor-stimulating effects of SNC80 develops after a single administration of SNC80 in rats; it is not known whether cross-tolerance develops to the effects of other stimulant compounds. In the initial studies to determine whether SNC80 produced cross-tolerance to other stimulant compounds, it was discovered that amphetamine-stimulated locomotor activity was greatly enhanced in SNC80-pretreated rats. This study evaluated acute cross-tolerance between δ-opioid agonists and other locomotor-stimulating drugs. Locomotor activity was measured in male Sprague-Dawley rats implanted with radiotransmitters, and activity levels were recorded in the home cage environment. Three-hour SNC80 pretreatment produced tolerance to further δ-opioid receptor stimulation but also augmented greatly amphetamine-stimulated locomotor activity in a dose-dependent manner. Pretreatments with other δ-opioid agonists, (+)BW373U86 [(+)-4-[α(R)-α-[(2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl]-3-hydroxybenzyl]-N,N-diethylbenzamide] and oxymorphindole (17-methyl-6,7-dehydro-4,5-epoxy-3,14-dihydroxy-6,7,2′,3′-indolomorphinan), also modified amphetamine-induced activity levels. SNC80 pretreatment enhanced the stimulatory effects of the dopamine/norepinephrine transporter ligands cocaine and nomifensine (1,2,3,4-tetrahydro-2-methyl-4-phenyl-8-isoquinolinanmine maleate salt), but not the direct dopamine receptor agonists SKF81297 [R-(+)-6-chloro-7,8-dihydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide] and quinpirole [trans-(-)-(4αR)-4,4a, 5,6,7,8,8a,9-octahydro-5-propyl-1H-pyrazolo[3,4-g] quinoline monohydrochloride]. In conclusion, SNC80 enhanced the locomotor-stimulating effects of monoamine transporter ligands suggesting that δ-opioid receptor activation might alter the functional activity of monoamine transporters or presynaptic monoamine terminals.
Cross sections for single electron capture, transfer ionization and direct ioniza-tion in Li3+- Ne collisions

Multiple ionization cross sections of Ne atoms are reported for Li3+ impact in the energy range of 2 to 5.8MeV. The neon ionization cross sections were separated into three collision channels, namely; direct ionization (DI), single capture (SC) and transfer ionization (TI). The direct ionization data is compared to CDW-EIS calculations as well as to other projectiles with charge state q = 3+. The single capture is compared to a modified Bohr-Lindhard semi classical model.
Effect of Moringa oleifera Leaf Powder Supplementation on Some Quality Characteristics of Wheat Bread

The effect of Moringa oleifera leaf powder supplementation on some physico-chemical and sensory properties of wheat bread was determined. Bread was prepared from varying proportions of 100%, 99%, 98%, 97%, 96% and 95% wheat flour supplemented with 0%, 1%, 2%, 3%, 4% and 5% Moringa oleifera leaf powder respectively. The bread samples were allowed to cool at ambient temperature (30˚C ± 1˚C) and analysed for some physical properties, proximate composition, and sensory attributes. Moringa leaf powder addition significantly (p < 0.05) increased the fibre (2.10% to 3.28%), ash (1.10% to 1.65%), protein (9.07% to 13.97%), and ether extract (1.51% to 2.59%), while decreasing moisture content (35.20% to 27.65%). Moringa leaf powder supplementation also significantly (p < 0.05) decreased the loaf volume, weight loss, loaf height and specific loaf volume from 796.70 to 496.70 cm 3 , 32.32 to 25.65 g, 7.00 to 5.83 cm and 4.70 to 2.65 cm 3 /g respectively, while the loaf weight increased from 169.20 to 185.86 g. There was a significant (p < 0.05) increase in Magnesium (Mg), Calcium (Ca) and Beta-carotene contents from 0.76 to 1.27 mg/100g, 3.67 to 6.07 mg/100g and 0.02 to 3.27 mg/100g respectively, while Iron (Fe) and Cupper (Cu) contents decreased from 2.74 to 1.25 mg/100g and 2.26 to 0.03 mg/100g respectively. Sensory evaluation showed that although there was significant (p < 0.05) improvement in nutritional composition, the acceptability of all bread samples decreased with increasing level of Moringa supplementation. This implies that despite the high nutrient content of Moringa oleifera powder, it is not a good substitute for wheat in bread production due to its physical characteristics and sensory attributes.
Relationships between yield and leaf nutrient contents in peach trees: Early nutritional status diagnosis

Abstract The objective was to determine to what extent foliar nutrient contents in different stages of the vegetative cycle are related to yield. The study was conducted on 180 peach trees (Prunus persica, L. Batsch) in several orchards located in the Ebro Basin. Leaf sampling (at 60, 90, 120, 150, and 180 days after full bloom) and crop harvesting were carried out individually on each of the 180 trees. Leaf samples were analyzed for N, P, K, Ca and Mg. The relationships of mineral analysis data (nutrient contents and their ten binary ratios) with yield were explored by applying three different calculation procedures. First, we analyzed the degree of significance of the differences in nutrient contents and binary ratios between two blocks of trees, separated according to yield level. This degree of significance was highest for leaf samples taken 60 and 120 days after full bloom, although the differences in K content and N/P and Ca/Mg ratios were not significant 120 days after full bloom. Second, we analyz.