scholarly journals Rheological and structural properties of lecithin-based organogels

2021 ◽  
Author(s):  
Karlene Stacey Tamara Singh
Keyword(s):  
Organic Phase ◽  
Soybean Lecithin ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Narrow Region ◽  
Polarised Light ◽  
Materials Used ◽  
Molecular Organisation ◽  
Dimensional Crystal

The objectives of this study were to develop lecithin-based organogels made of a biocompatible organic phase and to study the structural and rheological properties of organogels made with different organic phases. The materials used were soybean lecithin of >90% purity (phosphatidylcholine), distilled water and the following organic phases: isooctane (ISO), mineral oil (MO) and isopropylpalmitate (IPP). Phase diagrams for the PC/Water/ISO, PC/Water/ISO/MO (20:80 vo1/vo1), PC/Water/IPP,PC/Water/IPP/MO (50:50vo1/vo1 and 30:70vo1/vo1) and Pc/Water/MO systems were analysed using polarised light microscopy. A narrow region of organogel formation was observed in all systems at molar ratios of water to lecithin between values of 0.4 and 4, depending on the organic phase used. Small-angle X-ray diffraction studies for the PC/Water/ISO system revealed the existence of a highly ordered two-dimensional crystal lattice likely formed by the bundling of the cylindrical reverse micellar tubes. The results for the Pc/Water/IPP and PC/Water/MO systems indicated that there was not enough structural material in the organogels to observe any level of molecular organisation. In summary, this study demonstrated that it was possible to develop biocompatible lecithin-based organogels.

scholarly journals Rheological and structural properties of lecithin-based organogels

2021 ◽  
Author(s):  
Karlene Stacey Tamara Singh
Keyword(s):  
Organic Phase ◽  
Soybean Lecithin ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Narrow Region ◽  
Polarised Light ◽  
Materials Used ◽  
Molecular Organisation ◽  
Dimensional Crystal

The objectives of this study were to develop lecithin-based organogels made of a biocompatible organic phase and to study the structural and rheological properties of organogels made with different organic phases. The materials used were soybean lecithin of >90% purity (phosphatidylcholine), distilled water and the following organic phases: isooctane (ISO), mineral oil (MO) and isopropylpalmitate (IPP). Phase diagrams for the PC/Water/ISO, PC/Water/ISO/MO (20:80 vo1/vo1), PC/Water/IPP,PC/Water/IPP/MO (50:50vo1/vo1 and 30:70vo1/vo1) and Pc/Water/MO systems were analysed using polarised light microscopy. A narrow region of organogel formation was observed in all systems at molar ratios of water to lecithin between values of 0.4 and 4, depending on the organic phase used. Small-angle X-ray diffraction studies for the PC/Water/ISO system revealed the existence of a highly ordered two-dimensional crystal lattice likely formed by the bundling of the cylindrical reverse micellar tubes. The results for the Pc/Water/IPP and PC/Water/MO systems indicated that there was not enough structural material in the organogels to observe any level of molecular organisation. In summary, this study demonstrated that it was possible to develop biocompatible lecithin-based organogels.

scholarly journals Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 346
Author(s):  
Sonam Goyal ◽  
Maizatul Shima Shaharun ◽  
Ganaga Suriya Jayabal ◽  
Chong Fai Kait ◽  
Bawadi Abdullah ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalyst Support ◽  
Oxidation Potential ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Optimum Parameters ◽  
Reduction Of Co2 ◽  
Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

Organic Crystals in the Tracheids of Torreya Yunnanensis

IAWA Journal ◽  
1996 ◽  
Vol 17 (4) ◽  
pp. 393-403 ◽  
Author(s):  
Yuki Kondo ◽  
Tomoyuki Fujii ◽  
Yoshioki Hayashi ◽  
Atsushi Kato
Keyword(s):  
Phase Contrast ◽  
Growth Ring ◽  
Uv Spectra ◽  
Resonance Spectroscopy ◽  
Organic Crystals ◽  
X Ray Diffraction ◽  
Cinnamic Aldehyde ◽  
X Ray ◽  
Polarised Light ◽  
Contrast Microscopy

Organic crystals were found in tracheid lumina of some samples of Torreya yunnanensis Chen ' L. K. Fu imported from Yunnan, China. Tracheids with crystals were found in short to long tangential bands along the growth ring boundaries. Because the crystals were rapidly dissolved with ethanol and xylene, cross and tangential sections were mounted in de-ionized water without staining and observed by biological, polarised light, and phase-contrast microscopy. The crystals were sublimated under vacuum during routine sample preparation for conventional SEM and only the peripheral parts remained. With the aid of low vacuum-SEM and modified cryo-SEM procedure, the shape of the crystals was revealed. Some were styloid and large enough to fill tracheid lumina, while others were stacked appearing as slates filling tracheid lumina. X-ray diffraction applied to sections and isolated crystals showed that they were single crystals and orientated along the cell wall. UV spectra on isolated crystals and methanol dissolution of crystals suggested that they were composed of phenolic compounds. Crystals that were recrystallized from methanol were analysed by 1H and l3C nuclear magnetic resonance spectroscopy. These two techniques revealed that the major and minor components were o-methoxy cinnamic acid and o-methoxy cinnamic aldehyde.

Mitrofanovite, Pt3Te4, a new mineral from the East Chuarvy deposit, Fedorovo–Pana intrusion, Kola Peninsula, Russia

2018 ◽  
Vol 83 (4) ◽  
pp. 523-530 ◽  
Author(s):  
Victor V. Subbotin ◽  
Anna Vymazalová ◽  
František Laufek ◽  
Yevgeny E. Savchenko ◽  
Chris J. Stanley ◽  
...  
Keyword(s):  
Kola Peninsula ◽  
Electron Backscatter Diffraction ◽  
New Mineral ◽  
Synthetic Analogue ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural Identity ◽  
Polarised Light ◽  
Fe Alloys ◽  
Backscatter Diffraction

AbstractMitrofanovite, Pt3Te4, is a new telluride discovered in low-sulfide disseminated ore in the East Chuarvy deposit, Fedorovo–Pana intrusion, Kola Peninsula, Russia. It forms anhedral grains (up to ~20 μm × 50 μm) commonly in intergrowths with moncheite in aggregates with lukkulaisvaaraite, kotulskite, vysotskite, braggite, keithconnite, rustenburgite and Pt–Fe alloys hosted by a chalcopyrite–pentlandite–pyrrhotite matrix. Associated silicates are: orthopyroxene, augite, olivine, amphiboles and plagioclase. Mitrofanovite is brittle; it has a metallic lustre and a grey streak. Mitrofanovite has a good cleavage, along {001}. In plane-polarised light, mitrofanovite is bright white with medium to strong bireflectance, slight pleochroism, and strong anisotropy on non-basal sections with greyish brown rotation tints; it exhibits no internal reflections. Reflectance values for the synthetic analogue of mitrofanovite in air (Ro, Re’ in %) are: 58.4, 54.6 at 470 nm; 62.7, 58.0 at 546 nm; 63.4, 59.1 at 589 nm; and 63.6, 59.5 at 650 nm. Fifteen electron-microprobe analyses of mitrofanovite gave an average composition: Pt 52.08, Pd 0.19, Te 47.08 and Bi 0.91, total 100.27 wt.%, corresponding to the formula (Pt2.91Pd0.02)Σ2.93(Te4.02Bi0.05)Σ4.07 based on 7 atoms; the average of eleven analyses on synthetic analogue is: Pt 52.57 and Te 47.45, total 100.02 wt.%, corresponding to Pt2.94Te4.06. The density, calculated on the basis of the formula, is 11.18 g/cm3. The mineral is trigonal, space group R$\overline 3 $m, with a = 3.9874(1), c = 35.361(1) Å, V = 486.91(2) Å3 and Z = 3. The crystal structure was solved and refined from the powder X-ray-diffraction data of synthetic Pt3Te4. Mitrofanovite is structurally and chemically related to moncheite (PtTe2). The strongest lines in the powder X-ray diffraction pattern of synthetic mitrofanovite [d in Å (I) (hkl)] are: 11.790(23)(003), 5.891(100)(006), 2.851(26)(107), 2.137(16)(1013), 2.039(18)(0114), 1.574(24)(0120), 1.3098(21)(0027). The structural identity of natural mitrofanovite with synthetic Pt3Te4 was confirmed by electron backscatter diffraction measurements on the natural sample. The mineral name is chosen to honour Felix P. Mitrofanov, a Russian geologist who was among the first to discover platinum-group element mineralisation in the Fedorova–Pana complex.

X-Ray Studies on Phospholipid Bilayers. V. Interactions with DDT

1985 ◽  
Vol 40 (7-8) ◽  
pp. 566-570 ◽  
Author(s):  
M. Suwalsky ◽  
N. Bugueño ◽  
J. Tapia ◽  
F. Neira
Keyword(s):  
Phospholipid Bilayers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Lipid Mixtures ◽  
Oriented Films

Abstract The possible interaction of DDT with the lipids dimyristoyl lecithin (DML), dipalmitoylphos-phatidylethanolamine (DPPE) and tripalmitin (TP) was studied. The work was carried out on oriented films and crystalline powders of DDT-lipid mixtures at different molar ratios by X-ray diffraction techniques. The diagrams showed only the patterns of pure DDT and that of the corresponding lipid. It is concluded that new phases were not formed and, therefore, no interactions occurred.

scholarly journals Archaeometric Characterisation of Decorated Pottery from the Archaeological Site of Villa dei Quintili (Rome, Italy): Preliminary Study

Geosciences ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 172 ◽  
Author(s):  
Michela Ricca ◽  
Giuseppe Paladini ◽  
Natalia Rovella ◽  
Silvestro Antonio Ruffolo ◽  
Luciana Randazzo ◽  
...  
Keyword(s):  
Multidisciplinary Approach ◽  
Raw Materials ◽  
Archaeological Site ◽  
Optical Microscope ◽  
X Ray Diffraction ◽  
X Ray ◽  
Geochemical Study ◽  
Renaissance Period ◽  
Preliminary Study ◽  
Materials Used

This work focused on the study of decorated pottery dated back to the 16th century from the Roman archaeological site of Villa dei Quintili, a monumental complex located in the south-eastern part of Rome (Italy). A minero-petrographic and geochemical study was undertaken to analyse five archaeological samples in order to define textural features and raw materials used for their production, along with the chemical and physical composition of the superficial decorative glazed coatings. For this purpose, different analytical methods were used, such as polarising optical microscope (POM), X-ray diffraction (XRD), micro-Raman spectroscopy, X-Ray fluorescence (XRF), and electron microprobe analysis coupled with energy dispersive spectrometry (EMPA-EDS). The results of such a multidisciplinary approach allowed us to achieve important results crucial to recognise the shards as majolica of the Renaissance period, improving knowledge about manufacturing processes of these renowned painted ceramic artefacts.

Gold(I)-Bis(diphenylphosphino)amid und einige Gold(I)-Bis(diarylphosphino)methanide mit sterisch anspruchsvollen Arylsubstituenten / Gold(I)-bis(diphenylphosphino)amide and Some Gold(I)-bis(diarylphosphino)methanides with Bulkyl Aryl Substituents

1983 ◽  
Vol 38 (1) ◽  
pp. 62-66 ◽  
Author(s):  
Hubert Schmidbaur ◽  
Stefan Schnatterer ◽  
Kailash C. Dash ◽  
Aref A. M. Aly
Keyword(s):  
Spectroscopic Data ◽  
Ring Structure ◽  
Mossbauer Spectrum ◽  
X Ray Diffraction ◽  
Mössbauer Spectrum ◽  
X Ray ◽  
Molar Ratios ◽  
Tertiary Phosphines ◽  
Deep Yellow

Intensely yellow coloured, insoluble gold(I)-bis(diarylphosphino)amides, [(C6H5)P2NAu, 1, is obtained from lithiated bis(diphenylphosphino)amine and AuCl complexes of tertiary phosphines. 1 is assigned a dimeric eightmembered ring structure on the basis of its 197Au-Mößbauer spectrum and of a direct analogy with the corresponding bis(phosphino)methanide complexes, whose structure has recently been confirmed by X-ray diffraction. A series of mono- and binuclear AuCl complexes of bis(diarylphosphino)methanes bearing bulky 2-tolyl or 2,6-dimethylphenyl substituents (3a, b) was synthesized from the diphosphines and (CO)AuCl in the molar ratios 1:2 or 1:1. The compounds have structures 4 a, b and oa, b, respectively. An ionic tetrafluoroborate derivative 6 b was obtained from the chloride 5 b on treatment with AgBF4. Lithiation of the diphosphinomethanes 3 a, b using LiCH3 followed by reaction with CIAuPR3 complexes yields the deep-yellow Au(I) bis(diarylphosphino)methanides 7 a, b. All compounds, including the new ligand 3b and its precursor (2,6-(CH3)2C6H3)2PBr, 2, were characterized by analytical and spectroscopic data.

scholarly journals Darstellung und Kristallstrukturen von (PH4P)4Sb8I28 und (Ph4P)Sb3I10(Ph = C6H5) / Synthesis and Crystal Structures of (PH4P)4Sb8I28 and (Ph4P)Sb3I10(Ph = C6H5)

1987 ◽  
Vol 42 (12) ◽  
pp. 1493-1499 ◽  
Author(s):  
Siegfried Pohl ◽  
Wolfgang Saak ◽  
Detlev Haase
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Diffraction Data ◽  
Lone Pair ◽  
X Ray Diffraction ◽  
Triclinic Space Group ◽  
X Ray ◽  
Molar Ratios ◽  
Polymeric Chains ◽  
Bond Strengths

AbstractThe compounds (Pn4P)4Sb8I28 (1) and (Ph4P)Sb3I10 (2) were prepared by the reaction of SbI3 and Ph4PI in acetonitrile (molar ratios 2:1 and 3:1 respectively). The structures of 1 and 2 were determined from single crystal X-ray diffraction data.1 crystallizes in the triclinic space group P1̄ with a - 1321.7(5). b = 1346.7(5), c = 2201.8(8) pm, α = 104.18(2). β = 99.92(2), γ = 100.33(2)°; 2: monoclinic, C2/c, a = 2371.1(2), b = 745.0(1), c = 2495.1(2) pm, β = 100.75(1)°.Whereas 1 exhibits isolated Sb8I284- ions, the anions of 2 are built up of polymeric chains [Sb3I10- ]∞. In both compounds the distorted Sbl6 octahedra are linked by common edges. The Sb-I distances are in the range between 277.4 and 354.8 pm (1) and between 277.4 and 342.4 pm (2). The observed structures do not only depend on stoichiometry, the nature of the counter cations, and the possibility of oligomerisation but also on the wide variety of the Sb-I bond strengths and the different bridges formed by iodine.The lone pair of Sb(III) seems to be predominantly 5 s2.

Cathode Material Li [Li0.2 Mn0.44Ni0.18Co0.18]O2 Synthesized by Molten Salt Method

2013 ◽  
Vol 690-693 ◽  
pp. 981-984
Author(s):  
Guang Xin Fan ◽  
Hui Lian Li ◽  
Shu Pu Dai ◽  
Chuan Xiang Zhang ◽  
Xue Mao Guan ◽  
...  
Keyword(s):  
Molten Salt ◽  
Specific Area ◽  
Constant Current ◽  
Molar Ratio ◽  
Molten Salt Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Structures And Properties ◽  
Constant Current Charge

In this paper, LiOH·H2O and Li2CO3, which were widely used in industry and (Mn0.533Co0.233Ni0.233) (OH)2prepared by ourselves selected as starting materials, series materials of lithium-rich layered material Li [Li0.2Mn0.44Ni0.18Co0.18]O2were obtained by a molten salt method. Their structures and properties of the materials were investigated by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and constant current charge/discharge methods. The effects of different LiOH and Li2CO3molar ratios on the Li [Li0.2Mn0.44Ni0.18Co0.18]O2structures and properties were characterized. The results of the experiments indicate that The structures of the material such as crystal structure, the specific area, particle size distribution, tap densities were controlled by adjusting the proportion of the two lithium sources. Forthermore , when the molar ratio of LiOH and Li2CO3was 3:7, the maximum discharge capacity (214.77 mAhg-1) of the cathode was obtained.

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