Multi-scale structure, pasting and digestibility of adlay (Coixlachryma-jobi L.) seed starch

peer-reviewedThe hierarchical structure, pasting and digestibility of adlay seed starch (ASS) were investigated compared with maize starch (MS) and potato starch (PS). ASS exhibited round or polyglonal morphology with apparent pores/channels on the surface. It had a lower amylose content, a looser and more heterogeneous C-type crystalline structure, a higher crystallinity, and a thinner crystalline lamellae. Accordingly, ASS showed a higher slowly digestible starch content combined with less resistant starch fractions, and a decreased pasting temperature, a weakened tendency to retrogradation and an increased pasting stability compared with those of MS and PS. The ASS structure-functionality relationship indicated that the amylose content, double helical orders, crystalline lamellar structure, and surface pinholes should be responsible for ASS specific functionalities including pasting behaviors and in vitro digestibility. ASS showed potential applications in health-promoting foods which required low rearrangement during storage and sustainable energy-providing starch fractions

Analysis of swirling flow effects on the characteristics of unsteady hot-streak migration

AbstractThe temperature of flow at the combustor exit is inherently non-uniform and the hot fluid is called hot-streak. An in-house CFD software, NUAA-Turbo, was used to carry out 3D unsteady simulations on the PW-E3 single-stage high-pressure turbine. The hot-streak effect based on real stator and combustor counts was approximately evaluated by the contraction/dilatation method on the interface. The unsteady attenuation and migration process of hot-streaks in the turbine passage were well captured. The general performance parameters for different circumferential positions of hot-streaks were relatively consistent. Then, the influences of hot-streaks on blade surface temperature were investigated by comparing results under hot-streak and uniform inflow conditions. Unsteady simulations with combined inlet hot-streak and swirling flow show that the core of a hot-streak migrates to the tip under the influence of a positive swirl, while the phenomenon is just opposite with a negative swirl. Therefore, the heat transfer environment of rotor blades shows great differences with different directions of inlet swirl

1-Benzyl-2-phenyl-1H-benzimidazole–4,4′-(cyclo­hexane-1,1-di­yl)diphenol (1/1)

The asymmetric unit of the title co-crystal, C20H16N2·C18H20O2, contains one mol­ecule of 4,4′-(cyclo­hexane-1,1-di­yl)diphenol (in which the cyclo­hexane ring adopts a chair conformation) and one mol­ecule of 1-benzyl-2-phenyl-1H-benzimidazole, which are paired through an O—H⋯N hydrogen bond. These pairs are further linked by inter­molecular O—H⋯O hydrogen bonds into chains along [010]. Weak inter­molecular C—H⋯O and C—H⋯π inter­actions further consolidate the crystal packing. The dihedral angles between the pendant phenyl rings and the benzimidazole ring are 86.9 (2) and 43.1 (2)°

Bis[1-hydroxy­ethyl­idenediphosphon­ato(1−)](1,10-phenanthroline)nickel(II) mono­hydrate

In the mononuclear title compound, [Ni(C2H6O7P2)2(C12H8N2)]·H2O, the NiII atom (site symmetry 2) is bonded to two phosphate-based O,O′-bidentate chelate ligands and one N,N′-bidentate 1,10-phenanthroline ligand, resulting in a slightly distorted cis-NiN2O4 octa­hedral geometry. In the crystal structure, pairs of complexes are linked by double hydrogen bonds, forming a one-dimensional chain-like structure. Aromatic π–π stacking inter­actions [centroid–centroid separation = 3.768 (2) Å] and further hydrogen bonds generate a two-dimensional structure. The water O atom also lies on a crystallographic twofold axis

2,2′-(1,3,5,7-Tetra­oxo-1,2,3,5,6,7-hexa­hydro­pyrrolo[3,4-f]isoindole-2,6-di­yl)diacetic acid N,N-dimethyl­formamide disolvate

The asymmetric unit of the title compound, C14H8N2O8·2C3H7NO or L·2DMF (DMF = N,N-dimethyl­formamide), contains one half of the centrosymmetric mol­ecule L and one solvent mol­ecule, which is disordered between two orientations in a 0.555 (4):0.445 (4) ratio. Inter­molecular O—H⋯O hydrogen bonds link one L and two DMF mol­ecules into a centrosymmetric hydrogen-bonded cluster. The crystal packing is further stabilized by weak inter­molecular C—H⋯O hydrogen bonds

4,4′-Bipyridine–2,3,4,5,6-penta­fluoro­benzoic acid (1/2)

In the title 1:2 adduct, C10H8N2·2C7HF5O2, the complete 4,4′-bipyridine mol­ecule is generated by a crystallographic twofold axis. The components of the adduct are linked by inter­molecular O—H⋯N hydrogen bonds and further connected by a combination of C—H⋯O, C—H⋯F and F⋯F [2.859 (2) Å] inter­actions

2-(4-Carb­oxy­piperidinium-1-yl)pyridine-3-carboxyl­ate

The title compound, C12H14N2O4, crystallizes as a zwitterion. A negative charge is delocalized in the deprotonated carboxyl group attached to the pyridine ring. The piperidine N atom accepts a proton and the ring is transformed into a piperidinium cation. There is an intra­molecular N—H⋯O hydrogen bond between the protonated NH and a carboxyl­ate O atom. In the crystal, an O—H⋯O hydrogen bond between the carboxyl group and the carboxyl­ate O atom of another mol­ecule generates a helix along the b axis

2,2′,2′′,2′′′-(1,4-Phenyl­enedinitrilo)­tetra­acetic acid dihydrate

In the title compound, C14H16N2O8·2H2O, the complete organic molecule is generated by crystallographic inversion symmetry. The dihedral angles between the aniline ring and the acetic acid groups are almost identical, viz. 82.61 (7) and 80.33 (7)°. In the crystal, O—H⋯O hydrogen bonds link the organic mol­ecules and water mol­ecules, forming zigzag chains the c axis. An intra­molecular O—H⋯O hydrogen bond is also observed