scholarly journals Revisiting pure component wax esters as basis of wax-based oleogels

2021 ◽  
Author(s):  
Henriette Brykczynski ◽  
Till Wettlaufer ◽  
Eckhardt Flöter
Keyword(s):  
Crystal Structure ◽  
Chain Length ◽  
Binary Mixtures ◽  
Solid Phase ◽  
Pure Component ◽  
Wax Esters ◽  
Mixing Ratios ◽  
Ideal Mixing ◽  
Oscillatory Rheology ◽  
Chain Length Difference

Current research on wax-based oleogels indicates wax esters to be the key component in many natural waxes. This necessitates understanding the properties of pure wax esters to unravel the gelling mechanism in wax-based oleogels. Therefore, wax esters with different carbon numbers and symmetries were studied and characterized regarding their thermal (DSC) and viscoelastic (oscillatory rheology) behavior. Pure wax esters and binary mixtures of wax esters were studied as such and in oleogels formed in combination with medium chained triglyceride oil at WE-inclusion levels of 10 % (w/w). Interpretation of the observations was based on detailed analysis of pre-existing data on crystallographic (SAXS) and thermal properties. It is found that all observations concerning single pure WE’s obey a systematic framework linking molecular make up, crystal structure and behavior. The study on the gelling of four different binary mixtures of wax esters revealed that substantial chain length differences do have the expected consequence of separate crystallization. Mixtures of wax esters with only limited chain length difference reconfirmed earlier speculations on mixing and crystal structure. Applying mixtures of wax esters only differing in their position of the ester bond indicated ideal mixing behavior in the solid phase of the gels. Actually, the data revealed that despite these expected observations in both systems, additional thermal events occur at specific mixing ratios. Their supposed relation to compound formation certainly needs further confirmation. Rheological analysis confirmed that sequential crystallization results in highest firmness values for the systems studied.

Induced Smectic Phases I. Polymorphism in Binary Mixtures of Alkyloxybenzylidene-alkylanilines with Alkyl- and Alkyloxy- cyanobiphenyls

1981 ◽  
Vol 36 (1) ◽  
pp. 62-67 ◽  
Author(s):  
F. Schneider ◽  
N. K. Sharma
Keyword(s):  
Chain Length ◽  
Binary Mixtures ◽  
Transition Temperatures ◽  
Mean Values ◽  
Smectic Phases ◽  
The Mean ◽  
Induced Smectic Phases

The diagrams of state of mixtures of 4-n-alkyloxybenzylidene-4'-n-butylanilines with 4-n- alkyl- and 4-n-alkyloxy-4'-cyanobiphenyls are studied. The mixtures form induced smectic phases of type SA, SB and SE. In all three smectic phases the thickness of the smectic layers agrees with the mean values of the molecular lengths. In most cases the induced SA phases do not show uninterrupted miscibility with the SA phases of the pure components. For instance, the system 40 • 4/8 CBP exhibits three separate SA phase areas. The maximum transition temperatures of the induced smectic phases increase with increasing chain length of the azomethines, but remain constant in case of the SA and SB phases or even decrease in case of the SE phases with increasing chain length of the cyanobiphenyls

A general approach to the quantitation of synthetic efficiency in solid-phase peptide synthesis as a function of chain length

1984 ◽  
Vol 106 (25) ◽  
pp. 7845-7850 ◽  
Author(s):  
Virender K. Sarin ◽  
Stephen B. H. Kent ◽  
Alexander R. Mitchell ◽  
R. B. Merrifield
Keyword(s):  
Chain Length ◽  
Peptide Synthesis ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis ◽  
Synthetic Efficiency

Modeling Approaches to Accurately Predict Minimum Fluidization Characteristics of Gas-Solid Fluidized Beds

2012 ◽  
Author(s):  
Santhip Krishnan Kanholy ◽  
Francine Battaglia
Keyword(s):  
Binary Mixtures ◽  
Fluidized Beds ◽  
Solid Phase ◽  
Cfd Modeling ◽  
Particle Interactions ◽  
Dead Zones ◽  
Modeling Approaches ◽  
Minimum Fluidization ◽  
Computational Fluid Dynamics Cfd ◽  
Eulerian Modeling

The hydrodynamics of fluidized beds involving gas and particle interactions are very complex and must be carefully considered when using computational fluid dynamics (CFD). Modeling particle interactions are even more challenging for binary mixtures composed of varying particle characteristics such as diameter or density. One issue is the presence of dead-zones, regions of particles that do not fluidize and accumulate at the bottom, affecting uniform fluidization. In Eulerian-Eulerian modeling, the solid phase is assumed to behave like a fluid and the presence of dead zones are not typically captured in a simulation. Instead, the entire bed mass present in an experiment is modeled, which assumes full fluidization. The paper will present modeling approaches that account for only the fluidizing mass by adjusting the initial mass present in the bed using pressure drop and minimum fluidization velocity from experiments. In order to demonstrate the fidelity of the new modeling approach, different bed materials are examined. Binary mixture models are also validated for two types of mixtures consisting of glass-ceramic and ceramic-ceramic compositions. It will be shown that adjusting the mass in the modeling of fluidized beds best represents the measured quantities of an experiment for both single-phase and binary mixtures.

scholarly journals Miniaturized Analysis of Amylopectin Chain Length Distribution by Fluorescence-Assisted Capillary Electrophoresis (FACE) down to Single Starch Granules

2021 ◽  
Author(s):  
amandine pruvost ◽  
stanislas helle ◽  
nicolas szydlowski ◽  
Christian ROLANDO
Keyword(s):  
Capillary Electrophoresis ◽  
Chain Length ◽  
Solid Phase ◽  
Potato Starch ◽  
Relative Proportion ◽  
Length Distribution ◽  
Fluorescence Analysis ◽  
Starch Granules ◽  
Chain Length Distribution ◽  
Single Granule

In the present work, we developed a miniaturized method for determining amylopectin chain length distribution (CLD) by fluorescence-assisted capillary electrophoresis (FACE). The method relies on single granule entrapping into capillaries followed by direct starch gelatinization and amylopectin debranching on carbograph-based solid phase extraction (SPE) cartridges. Sample desalting on HypersepTM tips following APTS-labelling and the use of nanovials allowed for the fluorescence analysis of weakly diluted samples. Consequently, method sensitivity was improved by 500-fold which is compatible with the analysis of single potato starch granules. The method was implemented to determine CLD profiles of single starch granules ranging from 50 to 100 µm in diameter. In these experiments, the relative proportion of starch glucans of up to 30 degrees of polymerization (DP) could be quantified.

Study on the Properties of Doped La in BaBi4Ti4O15 Ceramic

2007 ◽  
Vol 26-28 ◽  
pp. 243-246
Author(s):  
Xing Hua Yang ◽  
Jin Liang Huang ◽  
Xiao Wang ◽  
Chun Wei Cui
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sintering Temperature ◽  
Solid Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lanthanum Content ◽  
Scanning Electron

BaBi4-xLaxTi4O15 (BBLT) ceramics were prepared by conventional solid phase sintering ceramics processing technology. The crystal structure and the microstructure were detected by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD analyses show that La3+ ions doping did not change the crystal structure of BBT ceramics. The sintering temperature increased from 1120°C to 1150°C with increasing Lanthanum content from 0 to 0.5, but it widened the sintering temperature range from 20°C to 50°C and refined the grain size of the BBT ceramic. Additionally, polarization treatment was performed and finally piezoelectric property was measured. As a result, the piezoelectric constant d33 of the 0.1at.% doped BBLT ceramics reached its highest value about 22pc/N at polarizing electric field of 8kV/mm and polarizing temperature of 120°C for 30min.

Effect of Sintering Temperatures and Ba/Ti Ratio on Dielectric Properties of BaTiO3 Ceramic

2013 ◽  
Vol 750-752 ◽  
pp. 506-511
Author(s):  
Yuan Yuan Li ◽  
Gui Xia Dong ◽  
Bi Yan Zhu ◽  
Qiu Xiang Liu ◽  
Di Wu
Keyword(s):  
Crystal Structure ◽  
Dielectric Properties ◽  
Curie Temperature ◽  
Sintering Temperature ◽  
Solid Phase ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Method Effect

As a research object, the samples with various Ba/Ti ratios (Ba/Ti=0.95~1.05) were synthesized by solid phase reaction method. Effect of sintering temperatures and Ba/Ti ratio on dielectric properties and crystal structure of BaTiO3ceramic were investigated. Crystal structure and crystal phase composition were investigated by scanning electron microscopy and X-ray diffraction. The dielectric properties were studied by Agilent 4294A at 1 kHz. The results show that the BaTiO3ceramic has high permittivity and dielectric loss at 1340°C. The permittivity of BaTiO3ceramic with Ba/Ti=0.95 change small as the sintering temperatures vary at 1320°C. With the increasing of Ba/Ti ratio, the Curie temperature first increases and then decreases as the sample sintering at 1320°C. When Ba/Ti=1, the Curie temperature increase with the sintering temperature increasing.

Non-Isothermal Phase Change Behaviors of Binary Mixtures of D-Dulcitol and Pentaerythritol As Novel Heat Storage Materials

2018 ◽  
Author(s):  
Xue-Feng Shao ◽  
Jun Wang ◽  
Li-Wu Fan
Keyword(s):  
Melting Point ◽  
Phase Change ◽  
Binary Mixtures ◽  
Latent Heat ◽  
Mass Fraction ◽  
Heat Storage ◽  
Solid Phase ◽  
Sugar Alcohols ◽  
Nucleation Agent ◽  
Latent Heat Storage

As a promising Phase Change Material (PCM) candidate for low-to-medium temperature (100–250 °C) latent heat storage, sugar alcohols undergo serious supercooling during cool-down for crystallization. Technical efforts need to be dedicated to suppression or control of the supercooling of sugar alcohols. In this work, the supercooling of D-dulcitol, with a melting point of around 186 °C, was attempted to be reduced by mixing with a solid-solid PCM Pentaerythritol (PE) as the nucleation agent, which has a solid-solid phase transition temperature (∼186 °C) similar to the melting point of d-dulcitol. Such novel binary mixtures were prepared by dispersing PE powders at various mass fractions into d-dulcitol melt. The non-isothermal phase-change-related properties, with emphasis on the crystallization properties, were tested on a heat-flux differential scanning calorimeter at a constant heating/cooling rate of 5 °C/min. The preliminary results showed that both the crystallization point and latent heat of crystallization strongly depend on the mass fraction of PE, and both decrease in magnitude with the increasing in mass fraction of PE. The degree of supercooling of the binary mixtures also depend on the mass fraction of PE, and a reduction of up to 10 °C was obtained at 50 wt.% PE, as a result of the decrease in the melting points of the binary mixtures.

Enthalpies of Mixing of Multicomponent Alkane Mixtures

1988 ◽  
Vol 41 (11) ◽  
pp. 1763 ◽  
Author(s):  
TJ Brady ◽  
S Weiguo ◽  
AG Williamson
Keyword(s):  
Chain Length ◽  
Binary Mixtures ◽  
Ternary Mixtures ◽  
Enthalpies Of Mixing

Enthalpies of mixing are reported for ternary n-alkane mixtures prepared from binary mixtures with large chain-length differences and at temperatures where the enthalpies of mixing of simple binary mixtures show changes of sign. In neither case does the behaviour of the ternary mixtures deviate significantly from that of the congruent binaries.

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