Top PDF Properties of α-monoclinic selenium

Properties of α-monoclinic selenium

Properties of α-monoclinic selenium

Chapter IV describes optical transmission measurements made on a-monoclinic crystals at room temperature and low temperatures, and on selenium dissolved in solvents... " -2- Also, polari[r]

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Facile Synthesis and Optical Properties of Small Selenium Nanocrystals and Nanorods

Facile Synthesis and Optical Properties of Small Selenium Nanocrystals and Nanorods

However, when these Se nanoparticles were cleaned up for several times by water, the dispersion solution changed to black color due to the growth of the particle size, which was larger than 50 nm. Some of the particles even grew up to nanorods with length of several hun- dreds of nanometers. Once glycerin was removed away from the surface of Se nanoparticles after cleaning process and let the particles age in air for more than 3 months, Se nanoparticles would lose activities and then grew up rapidly into nanorods along [022] or [110] dir- ection (Fig. 5). The morphology of these nanorods devel- oping from aging of small Se nanoparticles are demonstrated in Fig. 5. This kind of Se nanorods are rarely reported in the literatures [28 – 30]. The HRTEM image as well as Fourier transformation of the images for these Se nanorods are shown in Figs. 6 and 7, which display the hexagonal and monoclinic structure respect- ively. There are two nanorods in Fig. 6, both in hex- agonal structure. Rod A is in orientation of 0111 , while rod B in orientation of 1213 . The growth direc- tion of rod A and B are (110) and (001), respectively. However, the Se nanorod in Fig. 7 is in monoclinic struc- ture, which grows in the direction of (022). Therefore, the
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Selenium – a fascinating antioxidant of protective properties

Selenium – a fascinating antioxidant of protective properties

Natural selenium forms have also been found to show a protective effect under in vitro conditions. Two selenium- enriched medicines of herbal origin (IMOD and Angipars) (Rose Pharmed Biotechnology Co., Iran) were studied in an experiment performed on human lymphocytes. Both substances prevented the toxicity of an organophosphorus pesticide – chlorpyrifos. The beneficial influence included the amelioration of the chlorpyrifos-induced increase in TNF-α and reduction in cell apoptosis and necrosis. 54

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On the characteristic properties of geodesic sub- α, b, s -preinvex

On the characteristic properties of geodesic sub- α, b, s -preinvex

In the present work we study the properties of geodesic sub-(α, b, s)- preinvex functions on Hadamard manifolds and establish some basic properties in both general and differential cases. Further, we study sufficient conditions of optimality and proved some new inequalities under geodesic sub-(α, b, s)-preinvexity.

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Antifibrotic candidates of Selenium nanoparticles and selenium in the experimental model

Antifibrotic candidates of Selenium nanoparticles and selenium in the experimental model

This research was designed to compare the efficacy of selenium in nanoscale (SeNPs) with its free form (Se) against liver fibrosis induced by thioacetamide (TAA) in rats. In a completely randomized design, 60 adult female rats were distributed as: Group (1) control (received saline) and other three groups received TAA to induce liver fibrosis (100 mg/kg b.wt of three times a week for 6 weeks). Fifteen rats were termed TAA (Group 2). Rats in group (3) were simultaneously administered SeNPs (0.48 mg/kg/b.wt) orally (TAA+SeNPs). Rats in group (4) were simultaneously administered Se (0.48 mg/kg/b.wt) orally (TAA+Se). TAA injection enhanced liver enzymes activity, oxidative stress markers and inflammatory mediators, while suppressed the activity of the antioxidant enzymes activity versus the control group. SeNPs as well as Se supplementation blunted liver enzymes activity, oxidative stress indicators and inflammatory intermediates, while potentiated the activity of the antioxidant enzymes relative to TAA group. Histological investigation of liver tissue appreciated the biochemical findings. Aforementioned data clearly indicate that the mitigation of oxidative stress and inflammation may be the probable mechanisms by which SeNPs or Se can offer their antifibrotic action. Worth mentioning, SeNPs showed superior effect above Se in its free form in this respect.
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Selenium in Dermatology

Selenium in Dermatology

cytokines and their receptors selenium influence immune response or it makes immune cells more resistant to oxidative stress. It was reported that selenium supplementation had inhibitory effects on TNF-α levels in patients with psoriasis, selenium compounds are also known to prevent the in vitro release of UVB-induced pro- inflammatory cytokines by inhibition of mRNA in human keratinocytes. Fairris et al. reported that after 12 weeks supplementation of selenium and vitamin E, the patients mean whole blood, plasma and platelet selenium concentrations, platelet GSH-Px activity and plasma vitamin E concentration had risen significantly from the baseline values but their mean skin selenium concentration and red cell GSH-Px activity remained unchanged. The mean white cell selenium concentration rose only in the group receiving selenium alone. Neither supplementation regimen reduced the severity of psoriasis or produced side-effects. 2
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Further Properties of β Pascu Convex Functions of Order α

Further Properties of β Pascu Convex Functions of Order α

Many interesting properties such as coefficient estimate and distortion theorems for the class ᐀ᏼᏯ (p, m,α,β) were given by Ali et al. [2]. In the present sequel to these earlier works, we will derive several interesting properties and characteristic of the δ- neighborhood associated with the class ᐀ᏼᏯ(p, m,α,β).

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Selective Synthesis of Monoclinic Bismuth Vanadate Powders by Surfactant-Assisted Co-Precipitation Method: Study of Their Electrochemical and Photocatalytic Properties

Selective Synthesis of Monoclinic Bismuth Vanadate Powders by Surfactant-Assisted Co-Precipitation Method: Study of Their Electrochemical and Photocatalytic Properties

or near-ultraviolet radiation, which is only about 4% of the solar light spectrum reaching the earth surface. On the other hand, the visible light covers about 43% of the solar light. In order to efficiently utilize solar energy, the development of visible-light driven photocatalysts has attracted a tremendous amount of attention. Monoclinic bismuth vanadate (m-BiVO 4 ) is a material that has recently been used

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Investigation of hydrophobic moment and hydrophobicity properties for transmembrane α-helices

Investigation of hydrophobic moment and hydrophobicity properties for transmembrane α-helices

Hydrophobic moment plots for variable angular fre- quency were obtained for E( θ ) = 100° for each window size in the range (7 ≤ L ≤ 21) residues and for the separate standard deviation values, σ = 0.1°, 0.3°, 0.5°, 0.7°, 0.9°, 1.1°. These were compared visually with the original plots obtained under the fixed angular frequency assumption ( θ = 100°). In all cases, the bulk properties of the plots were similar irrespective of the level of dispersion intro- duced by the different values of the standard deviation. The hydrophobic moment plot for L = 15; θ = 100° is pro- vided in figure 7. This is to be contrasted with the plots for L = 15; E( θ ) = 100°, σ = 0.1°, σ = 0.7° and σ = 1.1°, also present in figure 7. Similar results were obtained for all other values, confirming, at least visually, that < µ H> is robust to slight random perturbations about a fixed value. These properties were also observed for the simulation study with the fixed angular frequency assumption being violated about the optimum frequency for each of the window sizes in the range (7 ≤ L ≤ 20) and for each corre- sponding level of dispersion.
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Selenium in reproduction

Selenium in reproduction

Moore, MA, Wander, RC, Xia, YM, Du, SH, Butler, JA & Whanger, PD 2000 Selenium supplementation of Chinese women with habitually low selenium intake increases plasma selenium, plasma glut[r]

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A new monoclinic polymorph of trans di­chloridodi­pyridine­palladium(II)

A new monoclinic polymorph of trans di­chloridodi­pyridine­palladium(II)

Data collection: APEX2 Bruker, 2004; cell refinement: SAINT Bruker, 2004; data reduction: SAINT; programs used to solve structure: SHELXTL Sheldrick, 2008; programs used to refine struct[r]

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Liming and selenium application effects on selenium uptake by maize (zea mays) and selenium contents in maize grain

Liming and selenium application effects on selenium uptake by maize (zea mays) and selenium contents in maize grain

The availability of selenium in soil solution as selenate (SeO 2 4  ) or selenite (SeO 2 3  ) ions is dependent upon the activity of electron (pe) and hydrogen (pH) of the solution. The plant uptake of SeO 2 4  ) is similar to that of sulphate (SO 2 4  ). Both SeO 2 4  and SO 2 4  enter root epidermal cells across the plasma membrane through sulphate transporters against their electrochemical gradients, with uptake being driven by the co- transport of three protons for each ion (Terry et al., 2000; Sors et al., 2005). SeO 2 4  uptake from the soil is through high- affinity sulphate transporters in plants (Terry et al. 2000; Sors et al., ibid.), whereas SeO 2 3  accumulates through passive diffusion and can be inhibited by phosphate (Terry et al., ibid.; Sors et al., ibid.). SeO 3 2  uptake in wheat is an active process, mediated by proton-coupled phosphate transporters (Li et al., 2008). It has been observed that SeO 2 4  ions are rapidly absorbed and transported in plant xylem sap and that SeO 3 2  absorption is slower, but the Se is more rapidly metabolized to
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A second monoclinic polymorph of methyl 4 hy­droxy­benzoate

A second monoclinic polymorph of methyl 4 hy­droxy­benzoate

The compound crystallizes in the space group Cc with three independent molecules in the asymmetric unit, similar to the first monoclinic polymorph (Vujovic & Nassimbeni, 2006). However, the cell parameters of the present monoclinic polymorph differ significantly from the previous polymorph [a = 13.006 (3) Å, b = 17.261 (4) Å, c = 12.209 (2) Å and β = 129.12 (3)°]. The corresponding bond lengths and angles of the three independent molecules agree with each other and also with those in the other monoclinic polymorph (Vujovic & Nassimbeni, 2006). Each of the independent molecules are planar. The dihedral angles formed by the C1A-C6A plane with the C1B-C6B and C1C-C6C planes are 2.9 (1)° and 71.2 (1)°, respectively. In the first monoclinic polymorph (Vujovic & Nassimbeni, 2006) these angles are 2.9 (1) and 1.4 (1)°.
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Monoclinic modification of 1,2 bis­­(di­phenyl­seleno­phosphino­yl)ethane

Monoclinic modification of 1,2 bis­­(di­phenyl­seleno­phosphino­yl)ethane

Diphenylphosphinoethane (dppe) was prepared according to literature (Lobana, 1992). To a mixture of 3.98 g (0.01 mol) dppe in 300 ml of dried chloroform was added 1.58 g (0.02 mol) of red selenium. The reaction mixture was refluxed overnight and filtered the unreacted Se out. The resulting solution was evaporated under reduced pressure. The crystals suitable for crystallography were obtained by recrystallization from chloroform-acetonitrile (1:1).

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A monoclinic polymorph of (nitrato κO)tetra­phenyl­anti­mony(V)

A monoclinic polymorph of (nitrato κO)tetra­phenyl­anti­mony(V)

Recently some organoantimony compounds have been reported by our group to possess potential biological activities (Yin et al., 2008). In a continuation of this study, we had synthesized the title compound and report its crystal structure herein. The crystal structure of a first polymorph of the title compound has been previously reported by Sharutin et al. (2002) in the triclinic space group P1, with a = 10.002 (2), b = 12.332 (2), c = 18.758 (5) Å, α = 73.54 (2), β = 75.59 (2), γ = 81.78 (2)°.

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Molecular Dynamics Simulation of Mechanical Properties for α SiO2 Crystal

Molecular Dynamics Simulation of Mechanical Properties for α SiO2 Crystal

oscillates between point B and point C with the strain increasing, this moment the nanocrystal appears amorphous phase transition. When the stress passes C in Figure 3, the crystal structure is completely amorphous, the stress reaches the peak value—fracture strength (36 GPa), the α -SiO 2 crystal enter the stage of

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2 (4 Fluoro­benzyl­­idene)propane­di­nitrile: monoclinic polymorph

2 (4 Fluoro­benzyl­­idene)propane­di­nitrile: monoclinic polymorph

A solution of 6-bromo-1-naphthol (0.01 mol) in EtOH (30 ml) was treated with 4-fluoro-1-(2,2-dicyanovinyl)benzene (0.01 mol) and piperidine (0.5 ml). The reaction mixture was heated until complete precipitation occurred (reaction time: 60 min). The solid product which formed was collected by filtration and recrystallized from ethanol to give the title compound, i.e. unreacted 4-fluoro-1-(2,2-dicyanovinyl)benzene, as both triclinic (Ng & Tiekink, 2013) and monoclinic (I) polymorphs. Both crystal forms have the appearance of yellow prisms.

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A monoclinic polymorph of 1 benzoyl 4 thio­biuret

A monoclinic polymorph of 1 benzoyl 4 thio­biuret

For the biological activity of thiadiazole derivatives, see: Piskala et al. (2004); Castro et al. (2008). For the structure and reactivity of thiadiazole derivatives, see: Cho et al. (1996). For the structure of a thiobiuret compound, see: Kang et al. (2012) and of the monoclinic polymorph, see: Kang (2013).

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Monoclinic form of 1 (di­cyclo­hexyl­thio­phosphinoyl) N phenyl­thio­form­amide

Monoclinic form of 1 (di­cyclo­hexyl­thio­phosphinoyl) N phenyl­thio­form­amide

Data collection: MSC/AFC Diffractometer Control Software Molecular Structure Corporation, 1996; cell re®nement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN Molecular [r]

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Monoclinic form of ethyl 4 amino­benzoate (benzocaine)

Monoclinic form of ethyl 4 amino­benzoate (benzocaine)

Ê CH3, and NÐH distances set to 0.88 A and 0.98 A Data collection: DENZO Otwinowski & Minor, 1997 and COLLECT Hooft, 1998; cell re®nement: DENZO and COLLECT; data reduction: DENZO and CO[r]

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