scholarly journals A combined approach using differential scanning calorimetry with polarized light thermomicroscopy in the investigation of ketoprofen and nicotinamide cocrystal

2017 ◽  
Vol 651 ◽  
pp. 1-10 ◽  
Author(s):  
G.L. Perpétuo ◽  
G.O. Chierice ◽  
L.T. Ferreira ◽  
T.F.C. Fraga-Silva ◽  
J. Venturini ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Polarized Light ◽  
Combined Approach ◽  
Scanning Calorimetry

scholarly journals Mesomorphism behaviour and photoluminescent properties of new asymmetrical 1,2-di(4-alkoxybenzylidene)hydrazines

2019 ◽  
Vol 43 (1-2) ◽  
pp. 67-77 ◽  
Author(s):  
Adil A Awad ◽  
Al-Ameen Bariz OmarAli ◽  
Ahmed Jasim M Al-Karawi ◽  
Zyad Hussein J Al-Qaisi ◽  
Samer Ghanim Majeed
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Polarized Light ◽  
Luminescent Properties ◽  
Scanning Calorimetry ◽  
Crystalline Materials ◽  
X Ray ◽  
Step Procedure ◽  
Liquid Crystalline Materials

{1-[4-( n-Alkoxy)]-2-(4’-decyloxy)benzylidene}hydrazines ( n-alkoxy = O(CH2) nH, n = 1–9, 12, 16 or 18), an asymmetrical series of 1,2-disubstituted hydrazines, were prepared in a simple two-step procedure as a part of our continuing work in evaluating hydrophobic azine compounds as photoluminescent liquid crystalline materials. The compounds were characterized spectroscopically and their liquid crystalline behaviour and luminescent properties were evaluated using polarized light optical microscopy, differential scanning calorimetry and X-ray powder diffraction techniques. The studies revealed that all of these compounds are liquid crystalline materials exhibiting photoluminescent properties in the crystalline and liquid crystal states.

scholarly journals Influence of Molecular Orientation on the Melting Behavior of Poly(phenylene sulfide) Fibers

2013 ◽  
Vol 8 (3) ◽  
pp. 155892501300800
Author(s):  
Prabhakar Gulgunje ◽  
Gajanan Bhat ◽  
Joseph Spruiell
Keyword(s):  
Differential Scanning Calorimetry ◽  
Molecular Orientation ◽  
Polarized Light ◽  
Melting Behavior ◽  
Probable Mechanism ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Phenylene Sulfide

The influence of molecular orientation on the melting behavior of draw-annealed poly(phenylene sulfide) fibers is investigated in the present paper. Tools used to probe the investigation were differential scanning calorimetry, polarized light optical microscopy, wide angle X-ray diffraction, and small angle X-ray diffraction. It is shown that molecular orientation in the crystalline and amorphous regions play a key role in crystal rearrangement during melting. A probable mechanism by which amorphous orientation influences crystal rearrangement is also discussed.

scholarly journals Utilization of unsaponifiable matter from rice bran oil fatty acid distillate for preparing an antioxidant-rich oleogel and evaluation of its properties

2020 ◽  
Vol 71 (1) ◽  
pp. 336
Author(s):  
S. Sahu ◽  
M. Ghosh ◽  
D. K. Bhattacharyya
Keyword(s):  
Differential Scanning Calorimetry ◽  
Fatty Acid ◽  
Light Microscopy ◽  
Unsaponifiable Matter ◽  
Rice Bran ◽  
Rice Bran Oil ◽  
Polarized Light ◽  
Weight Basis ◽  
Scanning Calorimetry ◽  
Fatty Acid Distillate

Rice bran oil fatty acid distillate (RBOFAD) is an important by-product obtained from the physical refining process. This fatty acid distillate contains high a amount of Unsaponifiable Matter (γ-oryzanol 3.27 gm/100gm UM; total tocopherol 10.93 mg/100 g UM; total phytosterol 21.81 g/100g UM; squalene 1.15 g/100 g UM and total fatty alcohol 73.34 g/100 g UM) and free fatty acids. Antioxidant-rich Oleogels were obtained from rice bran wax (RBW), rice bran oil fatty acid distillate (RBOFAD) and refined rice bran oil. The main objective of this study was to utilize the antioxidant-rich unsaponifiable matter of RBOFAD (UMRBOFAD) as an organogelator along with rice bran wax, which also acts as a good organogelator. Antioxidant-rich oleogel was prepared using UMRBFAD, ethylcellulose (EC) and RBW at 2%, 2%, 3% on weight basis, respectively, in refined rice bran oil and this antioxidant-rich oleogel was compared with rice bran oil oleogel using RBW at 7% on weight basis of rice bran oil. These oleogels were evaluated using a combination of techniques such as differential scanning calorimetry (DSC), polarized light microscopy (PLM), Viscosity, synchrotron radiation X-ray diffraction (SR-XRD) and FTIR Spectroscopy. The differential scanning calorimetry (DSC) measured the thermal properties of rice bran oil oleogel and high antioxidant-rich oleogel. Polarized light microscopy images revealed needle-like crystals for RBW. SR-XRD measurements were used for clarification of the crystal structures of the building blocks of these oleogels. The antioxidant activities of oleogels were evaluated involving DPPH and ABTS assays.

Characterization, liquid crystallinity and spin-coated films of some metalated 1,4,8,11,15,18,22,25-octaalkyl tetrabenzo [b,g,l,q][5,10,15]triazaporphyrin derivatives

2011 ◽  
Vol 15 (09n10) ◽  
pp. 890-897 ◽  
Author(s):  
Andrew N. Cammidge ◽  
Isabelle Chambrier ◽  
Michael J. Cook ◽  
Ernie H.G. Langner ◽  
Muhibur Rahman ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Optical Microscopy ◽  
Alkyl Chain ◽  
Bulk Material ◽  
Polarized Light ◽  
Scanning Calorimetry ◽  
Liquid Crystallinity ◽  
Derivatives Of ◽  
Deposited Films

The preparation and characterization of a number of metalated derivatives of 1,4,8,11,15,18,22,25-octahexyl and 1,4,8,11,15,18,22,25-octadecyl tetrabenzotriazaporphyrins (TBTAPs) are reported. The mesophase behavior of the compounds has been characterized by differential scanning calorimetry (DSC) and by polarized light optical microscopy. Mesophase behavior is compared with data for the corresponding phthalocyanine derivatives reported earlier. The temperature range of the mesophase(s) exhibited by the title compounds is generally broader than those of their phthalocyanine analogs. UV-vis data for examples of the TBTAP compounds as spin-coated films reveal differences in the type of molecular packing in the as-deposited films that is largely dependent upon the length of the alkyl chain substituents. On heating, the films undergo molecular reorganizations at temperatures corresponding to the mesophase transitions of bulk material observed by DSC.

scholarly journals Phase Behavior and DFT Calculations of Laterally Methyl Supramolecular Hydrogen-Bonding Complexes

Crystals ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 133 ◽  
Author(s):  
Hoda Ahmed ◽  
Mohamed Hagar ◽  
Omaima Alhaddad
Keyword(s):  
Differential Scanning Calorimetry ◽  
High Stability ◽  
Polarized Light ◽  
Supramolecular Complexes ◽  
Scanning Calorimetry ◽  
Methyl Group ◽  
Smectic C ◽  
Computational Calculations ◽  
Nematic Phases ◽  
Hydrogen Bonded

Four new series of laterally methyl-substituted hydrogen-bonded supramolecular complexes were prepared. The prepared complexes were thermally investigated by differential scanning calorimetry (DSC) and phases identified by polarized light microscopy (PLM). Supramolecular hydrogen-bonded complexes formed from a 1:1 mixture of any two derivatives, bearing different alkoxy chains, of 4-alkoxyphenylazobenzoic acid and 4-(2-(pyridin-4-yl)diazenyl-(2-(or 3-)methylphenyl) 4-alkoxybenzoate. The investigated 1:1 mixture made by introducing a lateral methyl group by different spatial orientation angles into pyridine-based components. All new complexes were confirmed by Fourier-transform infrared spectroscopy (FTIR) and computational calculations used to study their stabilities. It is found that the prepared complexes are dimorphic, exhibiting smectic C and enhanced nematic phases. A comparison was made between the new series and previously investigated simpler complexes, revealed that the incorporation of the phenylazo group elongate the mesogenic part and hence broad nematic phases were obtained with high stability.

Crystallization Behavior of Poly(lactic acid) Nucleated by a Hydrazide Compound

2013 ◽  
Vol 710 ◽  
pp. 85-88 ◽  
Author(s):  
Cheng Lang Li ◽  
Qiang Dou
Keyword(s):  
Differential Scanning Calorimetry ◽  
Lactic Acid ◽  
Crystallization Behavior ◽  
Polarized Light ◽  
Nucleating Agent ◽  
Poly Lactic Acid ◽  
Melt Blending ◽  
Scanning Calorimetry ◽  
Internal Mixer ◽  
Melting And Crystallization

A hydrazide compound (N-4) was used as a nucleating agent to induce the crystallization of poly (lactic acid) (PLA). PLA/N-4 samples were prepared by melt blending in an internal mixer. The melting and crystallization behavior and spherulitic morphology of the samples doped with different contents of N-4 were investigated by means of differential scanning calorimetry (DSC) and polarized light microscopy (PLM). It is found that the crystallization temperature and crystallinity increased but the spherulitic size of PLA decreased for the nucleated samples. It is indicated that N-4 is an effective nucleating agent for PLA.

scholarly journals Crystallization of polylactide-based green composites filled with oil-rich waste fillers

2020 ◽  
Vol 27 (12) ◽  
Author(s):  
Olga Mysiukiewicz ◽  
Mateusz Barczewski
Keyword(s):  
Differential Scanning Calorimetry ◽  
Oil Content ◽  
Crystallization Behavior ◽  
Polarized Light ◽  
Crystallization Rate ◽  
Environmental Issues ◽  
Oil Extraction ◽  
Green Composites ◽  
Scanning Calorimetry ◽  
Linseed Cake

AbstractPolylactide is a highly demanded biopolymer, whose industrial application constantly increases. Its disadvantages such as brittleness and slow crystallization rate can be overcome by application of different additives. Because of environmental issues, using natural waste fillers as modifying agents for polylactide is especially interesting. In this study linseed cake, a byproduct of oil extraction from linseed, characterized by oil content of 0.9–39.8 wt.%, was added to polylactide to influence its crystallization behavior. The formation of the crystalline phase was studied by differential scanning calorimetry in isothermal and non-isothermal conditions and analyzed according to methods by Jeziorny, Ozawa, Mo and Avrami. The samples’ microstructures were observed using polarized light microscopy. The crystallization rate and Avrami exponent of samples crystallized in different conditions were evaluated. It was found that addition of 10 wt.% of linseed cake containing at least 17.7 wt.% oil notably changes the crystallization of polylactide, increasing its crystallinity and promoting the growth of crystallites.

scholarly journals Development and Characterization of Nanostructured Pharmacosomal Mesophases: An Innovative Delivery System for Bioactive Peptides

2018 ◽  
Vol 8 (4) ◽  
pp. 609-615 ◽  
Author(s):  
Maryam Rezvani ◽  
Javad Hesari ◽  
Seyed Hadi Peighambardoust ◽  
Maria Manconi ◽  
Hamed Hamishehkar
Keyword(s):  
Differential Scanning Calorimetry ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Small Angle ◽  
Bioactive Peptides ◽  
Polarized Light ◽  
Scanning Calorimetry ◽  
X Ray ◽  
X Ray Scattering

Purpose: To potentially enhance the bioavailability and extend the bioactivity effectiveness of Isoleucine-Proline-Proline (IPP, an antihypertensive bioactive peptide of dairy origin), a novel Lyotropic Liquid Crystalline Pharmacosomal Nanoparticle (LLCPNP) was synthesized, and its physicochemical and technological characteristics were studied. Methods: LLCPNPs precursors were developed using IPP and soy phosphatidylcholine via complex formation. Polarized light microscopy, small angle X-ray scattering, differential scanning calorimetry, dynamic light scattering and Fourier transform infrared spectroscopy were employed to characterize the physicochemical properties of the nanoparticles. The in-vitro release and its related mechanisms were also studied. Results: Fourier transform infrared spectroscopy confirmed the complexation between the components of LLCPNPs. Phase behavior evaluation by polarized light microscope showed the characteristic birefringent texture. These findings along with those of small angle X-ray scattering and differential scanning calorimetry proved the formation of lamellar LLCPNPs. These particles represented nanometric size (<100 nm), high incorporation efficiency (93.72%) and proper physicochemical stability during long-term storage. In-vitro studies demonstrated a sustained release behavior fitted to non-Fickian diffusion and Higuchi kinetic models. Conclusion: The present study results emphasized that LLCPNPs could be proposed as an unrivaled carrier to promote the bioavailability, stability and shelf-life of nutraceutical and biopharmaceutical formulations containing bioactive peptides.

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