Monitoring both fat crystallization and self-assembly of sodium caseinate in model emulsions using synchrotron X-ray diffraction

2004 ◽  
pp. 139-145
Author(s):  
D. Kalnin ◽  
P. Quennesson ◽  
F. Artzner ◽  
O. Schafer ◽  
T. Narayanan ◽  
...  
Author(s):  
P. Vojtíšek ◽  
I. Císařová ◽  
J. Podlaha ◽  
Z. Žák ◽  
S. Böhm ◽  
...  

AbstractCrystal structures of the title compounds were determined by single crystal X-ray diffraction. Absolute configuration of the barium salt of (+)-(


2010 ◽  
Vol 74 ◽  
pp. 38-47
Author(s):  
Clay Mortensen ◽  
Paul Zschack ◽  
David C. Johnson

The evolution of designed [(Ti-Te)]x[(Sb-Te)]y, [(Bi-Te)]x[(Sb-Te)]y, [(Ti-Te)]w[(Bi-Te)]x[(Sb-Te)]y and [(Ti-Te)]w[(Bi-Te)]x[(Ti-Te)]y[(Sb-Te)]z precursors were followed as a function of annealing temperature and time using both low and high angle x-ray diffraction techniques to probe the self assembly into nanolaminate materials. The [(Bi-Te)]x[(Sb-Te)]y precursors were found to interdiffuse at low temperatures to form a (BixSb1-x)2Te3 alloy. The [(Ti-Te)]x[(Bi-Te)]y and [(Ti-Te)]x[(Sb-Te)]y precursors formed ordered nanolaminates [{(TiTe2)}1.35]x[Bi2Te3]y and [{(TiTe2)}1.35]x[Sb2Te3]y respectively. The [(Ti-Te)]w[(Bi-Te)]x[(Sb-Te)]x precursors formed [{(TiTe2)}1.35]w[(Bi0.5Sb0.5)2Te3]2x nanolaminates on annealing, as the bismuth and antimony layers interdiffused. Over the range of TiTe2 thicknesses used in [(Ti-Te)]w[(Bi-Te)]x[(Ti-Te)]y[(Sb-Te)]z precursors, Bi and Sb were found to interdiffuse through the 2-4 nm thick Ti-Te layers, resulting in the formation of (BixSb1-x)2Te3 alloy layers as part of the final nanolaminated products. When the Bi-Te and Sb-Te thicknesses were equal in the amorphous precursors, symmetric [{(TiTe2)}1.35]m[(Bi0.5Sb0.5)2Te3]n nanolamiantes were formed. When the thicknesses of Bi-Te and Sb-Te layers were not equal in the amorphous precursor, asymmetric [(TiTe2)1.35]m[(BixSb1-x)2Te3]n[(TiTe2)1.35]m[(BixSb1-x)2Te3]p nanolaminates were formed. These results imply that to form (A)w(B)x(C)y nanolaminates using designed layered precursors all three components must be immiscible. To form (A)x(B)y(A)x(C)z nanolaminates, the components must be immiscible or the precursor to the A component and the A component itself must be an effective interdiffusion barrier preventing B and C from mixing.


2013 ◽  
Vol 401-403 ◽  
pp. 663-666
Author(s):  
Xue Lian Bai ◽  
Jian Ting Mei ◽  
Zhong Guo Mu ◽  
Yun Bai

Polyaniline (PANI) nanotubes were synthesized separately using amino acetic acid (AA), ethylenediamine tetraacetic acid (EDTA), oxalic acid (OA) as dopant and ammonium persulfate (APS) as oxidant by a self-assembly method. SEM, TEM,FTIR and X-ray diffraction (XRD) and applying the 4 probes method characterized the morphology, structure and property of the product. It was found that nanotubes morphology were synthesized when the [Aci/[A ratio is 1:2.The room template conductivity of the products were studied.


Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 732
Author(s):  
Alexander A. Bredikhin ◽  
Aidar T. Gubaidullin ◽  
Zemfira A. Bredikhina ◽  
Robert R. Fayzullin ◽  
Olga A. Lodochnikova

Chiral recognition plays an important role in the self-assembly of soft materials, in particular supramolecular organogels formed by low molecular weight gelators (LMWGs). Out of 14 pairs of the studied racemic and enantiopure samples of alkyl-substituted phenyl ethers of glycerol, only eight enantiopure diols form the stable gels in nonane. The formation of gels from solutions was studied by polarimetry, and their degradation with the formation of xerogels was studied by the PXRD method. The revealed crystalline characteristics of all studied xerogels corresponded to those for crystalline samples of the parent gelators. In addition to those previously investigated, crystalline samples of enantiopure para-n-alkylphenyl glycerol ethers [alkyl = pentyl (5), hexyl (6), heptyl (7), octyl (8), nonyl (9)] and racemic 3-(3,5-dimethylphenoxy)propane-1,2-diol (rac-14) have been examined by single crystal X-ray diffraction analysis. Among 22 samples of compounds 1-14 studied by SC-XRD, seven different types of supramolecular motifs are identified, of which only two are realized in crystals of supramolecular gelators. An attempt was made to relate the ability to gel formation with the characteristics of the supramolecular motif of a potential gelling agent, and the frequency of formation of the motif, required for gelation, with the chiral characteristics of the sample.


2014 ◽  
Vol 10 ◽  
pp. 1613-1619 ◽  
Author(s):  
Simon Rondeau-Gagné ◽  
Jules Roméo Néabo ◽  
Maxime Daigle ◽  
Katy Cantin ◽  
Jean-François Morin

The synthesis and self-assembly of two new phenylacetylene macrocycle (PAM) organogelators were performed. Polar 2-hydroxyethoxy side chains were incorporated in the inner part of the macrocycles to modify the assembly mode in the gel state. With this modification, it was possible to increase the reactivity of the macrocycles in the xerogel state to form polydiacetylenes (PDAs), leading to a significant enhancement of the polymerization yields. The organogels and the PDAs were characterized using Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM).


2018 ◽  
Vol 74 (11) ◽  
pp. 1434-1439
Author(s):  
Hong-Tao Zhang ◽  
Xiao-Long Wang

In recent years, much initial interest and enthusiasm has focused on the self-assembly of coordination polymers due to the aesthetics of their crystalline architectures and their potential applications as new functional materials. As part of an exploration of chiral coordination polymers, a new twofold interpenetrated two-dimensional (2D) coordination polymer, namely, poly[[tetraaquabis[μ3-(2R,2′R)-2,2′-(benzene-1,4-dicarboxamido)dipropionato-κ5 O,O′:O′′,O′′′:O′′]dicadmium(II)] trihydrate], {[Cd2(C14H14N2O6)2(H2O)4]·3H2O} n , has been synthesized by the reaction of Cd(CH3COO)2·2H2O with the designed ligand (2R,2′R)-2,2′-(benzene-1,4-dicarboxamido)dipropionic acid (H2 L). The compound has been structurally characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analysis. In the crystal structure, each CdII cation binds to three carboxylate groups from two crystallographically independent L 2− dianions. Four carboxylate groups link two crystallographically independent cadmium cations into a 4,4-connected secondary building unit (SBU). The resulting SBUs are extended into a two-dimensional folding sheet via the terephthalamide moiety of the ligand as a spacer, which can be simplified as a (4,4)-connected 4,4L15 net with the point symbol (3.53.62)(32.52.62). In the lattice, two independent folding sheets interpenetrate each other to yield a double-sheet layer. The resulting 2D layers pack in parallel arrays through intermolecular hydrogen bonds and interlayer π–π interactions. The thermal stability and photoluminescence properties of the title compound have been investigated and it exhibits an enhanced fluorescence emission and a longer lifetime compared with free H2 L.


2020 ◽  
Vol 14 (2) ◽  
pp. 113-118
Author(s):  
Daniel Ursu ◽  
Anamaria Dabici ◽  
Marinela Miclau ◽  
Nicolae Miclau

We report for the first time the fabrication of hierarchical ordered superstructure CuB2O4 with flower-like morphology via a one-step, low temperature hydrothermal method. The tetragonal structure of CuB2O4 was determined by X-ray diffraction and high-resolution transmission electron microscopy. Optical measurements attested of the quality of the fabricated CuB2O4 and high temperature X-ray diffraction confirmed its thermal stability up to 600 ?C. The oriented attachment growth and the hierarchical self-assembly of micrometer-sized platelets producing hierarchical superstructures with flower-like morphology are designed by pH of the hydrothermal solution. The excellent band gap, high thermal stability and hierarchical structure of the CuB2O4 are promising for the photovoltaic and photocatalytic applications.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ali Asghar Hakami Zanjani ◽  
Nicholas P. Reynolds ◽  
Afang Zhang ◽  
Tanja Schilling ◽  
Raffaele Mezzenga ◽  
...  

Abstract By combining atomistic and higher-level modelling with solution X-ray diffraction we analyse self-assembly pathways for the IFQINS hexapeptide, a bio-relevant amyloid former derived from human lysozyme. We verify that (at least) two metastable polymorphic structures exist for this system which are substantially different at the atomistic scale, and compare the conditions under which they are kinetically accessible. We further examine the higher-level polymorphism for these systems at the nanometre to micrometre scales, which is manifested in kinetic differences and in shape differences between structures instead of or as well as differences in the small-scale contact topology. Any future design of structure based inhibitors of the IFQINS steric zipper, or of close homologues such as TFQINS which are likely to have similar structures, should take account of this polymorphic assembly.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Jiwoong Heo ◽  
Daheui Choi ◽  
Jinkee Hong

We demonstrate a simple method for fabricating multilayer thin films containing ferrite (Co0.5Zn0.5Fe2O4) nanoparticles, using layer-by-layer (LbL) self-assembly. These films have microwave absorbing properties for possible radar absorbing and stealth applications. To demonstrate incorporation of inorganic ferrite nanoparticles into an electrostatic-interaction-based LbL self-assembly, we fabricated two types of films: (1) a blended three-component LbL film consisting of a sequential poly(acrylic acid)/oleic acid-ferrite blend layer and a poly(allylamine hydrochloride) layer and (2) a tetralayer LbL film consisting of sequential poly(diallyldimethylammonium chloride), poly(sodium-4-sulfonate), bPEI-ferrite, and poly(sodium-4-sulfonate) layers. We compared surface morphologies, thicknesses, and packing density of the two types of ferrite multilayer film. Ferrite nanoparticles (Co0.5Zn0.5Fe2O4) were prepared via a coprecipitation method from an aqueous precursor solution. The structure and composition of the ferrite nanoparticles were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, transmission electron microscopy, and scanning electron microscopy. X-ray diffraction patterns of ferrite nanoparticles indicated a cubic spinel structure, and energy dispersive X-ray spectroscopy revealed their composition. Thickness growth and surface morphology were measured using a profilometer, atomic force microscope, and scanning electron microscope.


1994 ◽  
Vol 351 ◽  
Author(s):  
Astrid C. Zeppenfeld ◽  
Catherine J. Page

ABSTRACTIn order to investigate the influence of substrate functionalization on the subsequent selfassembly of multilayer films, multilayers composed of alternating hafnium and 1,10-decanediylbis(phosphonic) acid (DBPA) have been grown on three different substrates. Substrates studied include gold wafers functionalized with 4-mercaptobutylphosphonic acid, silicon wafers functionalized using a hafnium oxychloride solution, and silicon wafers coated with an octadecylphosphonate LB-template layer. The nature of these films is probed using ellipsometry and grazing angle x-ray diffraction. These studies indicate that the overall order and the individual layer thickness can vary substantially from sample to sample and depend strongly on the initial surface functionalization prior to multilayer growth.


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