THE BINARY (ANHYDROUS) SYSTEMS NaNO3–LiNO3, LiClO3–NaClO3, LiClO3–LiNO3, NaNO3–NaClO3 AND THE QUATERNARY SYSTEM NaNO3–LiNO3–LiClO3–NaClO3

1962 ◽  
Vol 40 (7) ◽  
pp. 1258-1265 ◽  
Author(s):  
A. N. Campbell ◽  
E. M. Kartzmark ◽  
M. K. Nagarajan
Keyword(s):  
Thermal Analysis ◽  
Sodium Nitrate ◽  
Binary Systems ◽  
Quaternary System ◽  
Sodium Chlorate ◽  
Eutectic Type ◽  
Lithium Nitrate ◽  
Allotropic Transformation ◽  
X Ray ◽  
Invariant Points

The equilibrium diagrams of the systems NaNO3–LiNO3, LiClO3–NaClO3, LiClO3–LiNO3, NaNO3–NaClO3, and NaNO3–LiNO3–LiClO3–NaClO3 have been investigated by thermal analysis and, to some extent, by X-ray powder photography. All the binary systems are of the simple eutectic type, accompanied, in one instance, by considerable solid solubility. The allotropic transformation of sodium nitrate complicates the equilibria involving sodium nitrate somewhat, especially when there is solid solution.The quaternary diagram shows that in the (fused) reaction[Formula: see text]lithium nitrate and sodium chlorate constitute the stable solid pair. The two invariant points of this system are both congruent.

Studies on the thermodynamics and conductances of molten salts and their mixtures. Part VI. Calorimetric studies of sodium chlorate and its mixtures with sodium nitrate

1968 ◽  
Vol 46 (8) ◽  
pp. 1287-1291 ◽  
Author(s):  
A. N. Campbell ◽  
E. T. van der Kouwe
Keyword(s):  
Sodium Nitrate ◽  
Molten Salts ◽  
Sodium Chlorate ◽  
Heat Of Fusion ◽  
Heat Of Mixing ◽  
Lithium Nitrate ◽  
Entropy Of Fusion ◽  
Direct Experiment ◽  
Calorimetric Studies ◽  
Nitrate System

The following properties have been determined by direct experiment for pure sodium chlorate and its mixtures with sodium nitrate: heat capacity (both solid and liquid) and heat of fusion. From these experimental quantities, the following properties have been derived: entropy of fusion, heat of mixing, and free energy and entropy of mixing. The results have been compared with our previous results for the corresponding lithium chlorate – lithium nitrate system. On the whole, the conclusion is justified that the structure of melts containing lithium chlorate is more complex than that of melts involving sodium chlorate.

THE SYSTEM LITHIUM NITRATE–ETHANOL–WATER AND ITS COMPONENT BINARY SYSTEMS

1958 ◽  
Vol 36 (3) ◽  
pp. 518-536 ◽  
Author(s):  
A. N. Campbell ◽  
R. A. Bailey
Keyword(s):  
Powder Diffraction ◽  
Binary Systems ◽  
Equilibrium Diagram ◽  
High Viscosity ◽  
Lithium Nitrate ◽  
Dilute Solution ◽  
Alcohol Content ◽  
Peritectic Point ◽  
X Ray ◽  
Pseudobinary Systems

The system lithium nitrate–water has been investigated by thermal analysis and by X-ray powder diffraction studies. No trace of the hemihydrate reported by Donnan and Burt was found. The X-ray powder diffraction pattern of LiNO3.3H2O has been obtained.The equilibrium diagram of the system ethanol–water shows an inflection at –30 °C, corresponding to 40 weight per cent ethanol. This is almost certainly a true peritectic point. The formula of the hydrate formed (if there is one) is uncertain but it may be C2H5OH.5H2O.The system lithium nitrate–ethanol could only be studied in dilute solution (of lithium nitrate) and at temperatures near room temperature, because of high viscosity and extreme supercooling. No evidence for the existence of a solid alcoholate has been obtained.The system lithium nitrate–ethanol–water has been investigated in the form of a series of pseudobinary systems containing water and alcohol in fixed ratios. No solid alcoholate of lithium nitrate has been found in solutions containing less than 50 weight per cent ethanol. The investigation could not be pushed beyond this alcohol content because of high viscosity and supercooling.

Lithium and Ammonium Selenates

1995 ◽  
Vol 60 (6) ◽  
pp. 969-976 ◽  
Author(s):  
David Havlíček ◽  
Zdeněk Mička ◽  
Radka Boublíková
Keyword(s):  
Thermal Analysis ◽  
Dielectric Properties ◽  
Quaternary System ◽  
Analysis Data ◽  
Thermal Analysis Data ◽  
X Ray ◽  
Crystallization Region

The Li2SeO4-H2SeO4-H2O and (NH4)2SeO4-Li2SeO4-H2O systems were studied at 30 °C to obtain data for determining the conditions of formation of the compound (NH4)4LiH3(SeO4)4, whose characteristics correspond to those of substances possessing significant dielectric properties. The results were used to construct the pseudoternary LiNH4SeO4-NH4HSeO4 -H2O section in the quaternary system, which gave evidence that only (NH4)3H(SeO4)2 forms in the crystallization region of the compound sought. Attention was also paid to lithium ammonium selenate, which was characterized by its X-ray, spectral, and thermal analysis data.

Studies on the thermodynamics and conductances of molten salts and their mixtures. Part V. The density, change of volume on fusion, viscosity, and surface tension of sodium chlorate and of its mixtures with sodium nitrate

1968 ◽  
Vol 46 (8) ◽  
pp. 1279-1286 ◽  
Author(s):  
A. N. Campbell ◽  
E. T. van der Kouwe
Keyword(s):  
Activation Energy ◽  
Surface Tension ◽  
Sodium Nitrate ◽  
Molten Salts ◽  
Sodium Chlorate ◽  
Surface Heat ◽  
Lithium Nitrate ◽  
Positive Deviation ◽  
Molten Sodium ◽  
Salt Melts

The densities, viscosities, and surface tensions of molten sodium chlorate, and of molten mixtures of sodium chlorate and sodium nitrate, as well as the change of volume on fusion, have been determined.From the dependence of molar volume on temperature and composition, it appears that the mixing of sodium chlorate and sodium nitrate is a process of dilution rather than of interaction. The viscosity of sodium chlorate is found to be much lower than that of lithium chlorate, a possible indication of greater complexity in the lithium chlorate melt. The activation energy of viscous flow for sodium chlorate is less than that of lithium chlorate. For lithium chlorate – lithium nitrate mixtures, at constant temperature, there is pronounced positive deviation from linearity, when viscosity is plotted against molar composition. For sodium chlorate – sodium nitrate mixtures, the deviation is much less marked though still positive.The surface tension of sodium chlorate is almost identical with those of lithium and potassium chlorates. The surface heat of sodium chlorate is higher than that of lithium chlorate but it still indicates some degree of covalency. The Guggenheim formula and Sokolov's rule have been applied. In contrast to melts of mixtures of lithium chlorate and lithium nitrate, the sodium salt melts would appear to have simpler constituents and to be more ionic in character.

Fractionation of polymethylene chains: An electron crystallographic investigation

1986 ◽  
Vol 44 ◽  
pp. 794-795
Author(s):  
Douglas L. Dorset
Keyword(s):  
Cross Section ◽  
Binary Systems ◽  
Linear Chain ◽  
Pure Component ◽  
Organic Substrates ◽  
Crystallographic Investigation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molecular Sizes ◽  
The Stability

A variety of linear chain materials exist as polydisperse systems which are difficultly purified. The stability of continuous binary solid solutions assume that the Gibbs free energy of the solution is lower than that of either crystal component, a condition which includes such factors as relative molecular sizes and shapes and perhaps the symmetry of the pure component crystal structures.Although extensive studies of n-alkane miscibility have been carried out via powder X-ray diffraction of bulk samples we have begun to examine binary systems as single crystals, taking advantage of the well-known enhanced scattering cross section of matter for electrons and also the favorable projection of a paraffin crystal structure posited by epitaxial crystallization of such samples on organic substrates such as benzoic acid.

PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

2016 ◽  
Vol 5 (1) ◽  
pp. 6
Author(s):  
Budi Setiawan ◽  
Erizal Zaini ◽  
Salman Umar
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Differential Thermal Analysis ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
Poloxamer 188 ◽  
X Ray ◽  
Scanning Electron

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan  (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan  (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik  menggunakan analisis varian satu arah  SPSS 17.

Interaction of ditertiary phosphines with phenyl- and 1-naphthyldithiocarbamatonickel(II)

1985 ◽  
Vol 50 (6) ◽  
pp. 1383-1390
Author(s):  
Aref A. M. Aly ◽  
Ahmed A. Mohamed ◽  
Mahmoud A. Mousa ◽  
Mohamed El-Shabasy
Keyword(s):  
Thermal Analysis ◽  
Powder Diffraction ◽  
Spin Structure ◽  
Magnetic Measurements ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
X Ray ◽  
Square Planar

The synthesis of the following mixed ligand complexes is reported: [Ni(phdtc)2(dpm)2], [Ni(phdtc)2(dpe)2], [Ni(phdtc)2(dpp)3], [Ni(1-naphdtc)2(dpm)2], [Ni(1-naphdtc)2], and [Ni(1-naphdtc)2(dpp)2], where phdtc = PhNHCSS-, 1-naphdtc = 1-NaPhNHCSS-, dpm = Ph2PCH2PPh2, dpe = Ph2P(CH2)2PPh2, and dpp = Ph2P(CH2)3PPh2. The complexes are characterised by microanalysis, IR and UV-Vis spectra, magnetic measurements, conductivity, X-ray powder diffraction, and thermal analysis. All the mixed ligand complexes are diamagnetic, and thus a square-planar or square-pyramidal (low-spin) structure was proposed for the present complexes.

scholarly journals X-ray and UV emission of the ultrashort-period, low-mass eclipsing binary system BX Trianguli

2018 ◽  
Vol 619 ◽  
pp. A138
Author(s):  
V. Perdelwitz ◽  
S. Czesla ◽  
J. Robrade ◽  
T. Pribulla ◽  
J. H. M. M. Schmitt
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Binary Systems ◽  
Uv Light ◽  
Close Binary ◽  
Eclipsing Binary ◽  
X Ray ◽  
Uv Emission ◽  
Low Mass ◽  
Orbital Modulation

Context.Close binary systems provide an excellent tool for determining stellar parameters such as radii and masses with a high degree of precision. Due to the high rotational velocities, most of these systems exhibit strong signs of magnetic activity, postulated to be the underlying reason for radius inflation in many of the components. Aims.We extend the sample of low-mass binary systems with well-known X-ray properties. Methods.We analyze data from a singular XMM-Newton pointing of the close, low-mass eclipsing binary system BX Tri. The UV light curve was modeled with the eclipsing binary modeling tool PHOEBE and data acquired with the EPIC cameras was analyzed to search for hints of orbital modulation. Results.We find clear evidence of orbital modulation in the UV light curve and show that PHOEBE is fully capable of modeling data within this wavelength range. Comparison to a theoretical flux prediction based on PHOENIX models shows that the majority of UV emission is of photospheric origin. While the X-ray light curve does exhibit strong variations, the signal-to-noise ratio of the observation is insufficient for a clear detection of signs of orbital modulation. There is evidence of a Neupert-like correlation between UV and X-ray data.

scholarly journals Struvite Grown in Gel, Its Crystal Structure at 90 K and Thermoanalytical Study

Crystals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 89 ◽  
Author(s):  
Jolanta Prywer ◽  
Lesław Sieroń ◽  
Agnieszka Czylkowska
Keyword(s):  
Thermal Analysis ◽  
Sodium Metasilicate ◽  
X Ray Diffraction ◽  
Gel Growth ◽  
Growth Technique ◽  
Thermoanalytical Study ◽  
X Ray ◽  
Cell Parameters ◽  
Thermal Analysis Techniques ◽  
Derivative Thermogravimetry

In this article, we report the crystallization of struvite in sodium metasilicate gel by single diffusion gel growth technique. The obtained crystals have a very rich morphology displaying 18 faces. In this study, the habit and morphology of the obtained struvite crystals are analyzed. The crystals were examined and identified as pure struvite by single X-ray diffraction (XRD). The orthorhombic polar noncentrosymmetric space group Pmn21 was identified. The structure of the crystal was determined at a temperature of 90 K. Our research indicates a lack of polymorphism, resulting from the temperature lowering to 90 K, which has not been previously reported. The determined unit cell parameters are as follows a = 6.9650(2) Å, b = 6.1165(2) Å, c = 11.2056(3) Å. The structure of struvite is presented here with a residual factor R1 = 1.2% at 0.80 Å resolution. We also present thermoanalytical study of struvite using thermal analysis techniques such as thermogravimetry (TG), derivative thermogravimetry (DTG) and differential thermal analysis (DTA).

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