1,067 research outputs found
Tetra(chlorido/iodido)(1,10-phenanthroline)platinum(IV) hemi[di(chlorine/iodine)]
The asymmetric unit of the title compound, [PtCl3.66I0.34(C12H8N2)]·0.5(Cl0.13I1.87), contains a neutral PtIV complex and one half of a halogen molecule. The PtIV ion is six-coordinated in a distorted octahedral environment by two N atoms of the 1,10-phenanthroline ligand and Cl or I atoms. The refinement of the structure and the EDX analysis indicate that the compound is a solid solution in which there is some substitution of Cl for I and vice versa. The chemical formula of the pure state of the compound would have been [PtCl4(C12H8N2)]·0.5I2. In the analysed crystal, two Cl atoms are partially (ca 25% and 9%) replaced by I atoms, and the I2 molecule has a minor component modelled as ICl. As a result of the disorder, the different trans effects of the N and Cl/I atoms are not distinct. The complex displays intermolecular π–π interactions between the six-membered rings, with a centroid–centroid distance of 3.771 (4) Å. There are also weak intramolecular C—H⋯Cl hydrogen bonds
4,11-Diaza-1,8-diazoniacyclotetradecane bis(pyridine-2-carboxylate) dihydrate
The asymmetric unit of the title compound, C10H26N4
2+·2C6H4NO2
−·2H2O, consists of half of a doubly protonated 1,4,8,11-tetraazacyclotetradecane (cyclam) dication, a pyridine-2-carboxylate anion and a solvent water molecule. The complete dication is generated by a crystallographic centre and adopts an endodentate conformation which may be influenced by intramolecular N—H⋯N hydrogen bonding. The carboxylate group of the anion appears to be delocalized on the basis of the C—O bond lengths [1.257 (2) and 1.250 (2) Å]. In the crystal structure, the components are linked by intermolecular N—H⋯O, N—H⋯N and O—H⋯O hydrogen bonds
6,12-Dihydrodipyrido[1,2-a:1′,2′-d]pyrazinium bis(perchlorate)
In the title compound, C12H12N2
2+·2ClO4
−, the dihedral angle between the two outer pyridine rings of the dication is 44.8 (1)°. In the crystal, weak intermolecular C—H⋯O hydrogen bonds occur
Butane-1,4-diammonium bis(pyridine-2-carboxylate) monohydrate
The asymmetric unit of the title compound, C4H14N2
2+·2C6H4NO2
−·H2O, consists of half of a doubly protonated tetramethylenediammonium dication, a pyridine-2-carboxylate anion and half of a solvent water molecule; the dication is located on a centre of inversion and a twofold rotation axis passes through the O atom of the water molecule. The carboxylate group of the anion appears to be delocalized on the basis of the C—O bond lengths. In the crystal structure, the components are linked by intermolecular N—H⋯O, N—H⋯N and O—H⋯O hydrogen bonds
Solutions of in
Though it is well known that the roots of any affine polynomial over a finite
field can be computed by a system of linear equations by using a normal base of
the field, such solving approach appears to be difficult to apply when the
field is fairly large. Thus, it may be of great interest to find an explicit
representation of the solutions independently of the field base. This was
previously done only for quadratic equations over a binary finite field. This
paper gives an explicit representation of solutions for a much wider class of
affine polynomials over a binary prime field
Cyclohexane-1,2-diammonium bis(pyridine-2-carboxylate)
In the dication of the title salt, C6H16N2
2+·2C6H4NO2
−, the two ammonium groups are in the equatorial positions of the chair-shaped cyclohexyl ring. In the crystal, the cations and anions are linked by N—H⋯O and N—H⋯N hydrogen bonds, forming a layer network parallel to the ac plane. Weak π–π interactions between adjacent pyridine rings with a centroid–centroid distance of 3.589 (2) Å are also present
Bis(2,2′-bipyridine-κ2 N,N′)dichloridoplatinum(IV) dichloride monohydrate
In the title complex, [PtCl2(C10H8N2)2]Cl2·H2O, the Pt4+ ion is six-coordinated in a distorted octahedral environment by four N atoms from the two 2,2′-bipyridine ligands and two Cl atoms. As a result of the different trans influences of the N and Cl atoms, the Pt—N bonds trans to the Cl atom are slightly longer than those trans to the N atom. The compound displays intermolecular hydrogen bonding between the water molecule and the Cl anions. There are intermolecular π–π interactions between adjacent pyridine rings, with a centroid–centroid distance of 3.962 Å
Non-Einstein Viscosity Phenomenon of Acrylonitrile–Butadiene–Styrene Composites Containing Lignin–Polycaprolactone Particulates Highly Dispersed by High-Shear Stress
Lignin powder was modified via ring-opening polymerization of caprolactone to form a lignin–polycaprolactone (LPCL) particulate. The LPCL particulates were mixed with an acrylonitrile–butadiene–styrene (ABS) matrix at an extremely high rotational speed of up to 3000 rpm, which was achieved by a closed-loop screw mixer and in-line melt extruder. Using this high-shear extruding mixer, the LPCL particulate size was controlled in the range of 3395 nm (conventional twin-screw extrusion) down to 638 nm (high-shear mixer of 3000 rpm) by altering the mixing speed and time. The resulting LPCL/ABS composites clearly showed non-Einstein viscosity phenomena, exhibiting reduced viscosity (2130 Pa·s) compared to the general extruded composite one (4270 Pa·s) at 1 s–1 and 210 °C. This is due to the conformational rearrangement and the increased free volume of ABS molecular chains in the vicinity of LPCL particulates. This was supported by the decreased glass transition temperature (Tg, 83.7 °C) of the LPCL/ABS composite specimens, for example, giving a 21.8% decrement compared to that (107 °C) of the neat ABS by the incorporation of 10 wt % LPCL particulates in ABS. The LPCL particulate morphology, damping characteristics, and light transmittance of the developed composites were thoroughly investigated at various levels of applied shear rates and mixing conditions. The non-Einstein rheological phenomena stemming from the incorporation of LPCL particulates suggest an interesting plasticization methodology: to improve the processability of high-loading filler/polymer composites and ultra-high molecular weight polymers that are difficult to process because of their high viscosity
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