This work addresses the surface properties and solubility parameters of sodium alginate (SA) using the inverse gas chromatography (IGC) technique. The dispersive component of the surface free energy,γS D, of the studied adsorbent surface was calculated in the infinite dilution region. The specific enthalpy of adsorption,ΔH S, the specific free energy of adsorption, ΔG S, and the specific entropy of adsorption, ΔS S, of solvents on SA were determined. The acidic K A and the basic K D parameters of the SA surface were calculated. The values obtained for K A and K D parameters indicated that the SA surface has a basic character. The interactions between 16 solvents and SA were investigated at a temperature range (373.2–398.2 K). The weight fraction activity coefficient,Ω1 ∞, Flory–Huggins interaction parameter, χ12 ∞, equation-of-state interaction parameter, χ12 *, and effective exchange energy parameter, X eff, of the SA–solvent system were estimated. The results indicated that all the studied solvents are poor solvents for SA. This means that it can be used in the packaging food and biomedical field. The solubility parameter of SA, δ2, was determined as 17.5 (cal/cm3)1/2.

It was determined that the thermal stability of poly(4-methyl-1-pentene) (P4MP) was maintained up to 424 C in an inert atmosphere by thermogravimetric analysis. The retention diagrams of ethyl acetate, tert-butyl acetate, and benzene on P4MP were plotted at temperatures between 30 and 280 C by inverse gas chromatography (IGC) technique. Melting temperature of the polymer was determined as 230 and 239.5C by IGC and differential scanning calorimetry (DSC), respectively. The percent crystallinity of P4MP was obtained from the retention diagrams at temperatures below melting point. , and effective exchange energy parameter, X eff of octane, nonane, decane, undecane, dodecane, tridecane, n-butyl acetate, isobutyl acetate, isoamyl acetate with P4MP, were determined between 240 and 280 C by IGC.

The synthesis, characterisation and mesomorphic properties of a new chiral liquid crystal, (S)-5-(10-undecenyloxy)-2- [[[4-(2-methylbutoxy)phenyl]imino]methyl]phenol (UMBPIMP) are described. The phase transition temperatures of this mesogenic compound have been investigated by optical polarising microscopy, differential scanning calorimetry and inverse gas chromatography. The thermodynamics of UMBPIMP were investigated in order to understand its selectivity as a stationary phase in gas chromatography. Its liquid crystal selectivity was tested using the isomers nbutyl acetate, tert-butyl acetate and iso-butyl acetate, and the isomers n-butyl alcohol, tert-butyl alcohol and iso-butyl alcohol, as model chromatographic probes. The retention diagrams of the isomers were plotted between 30 C and 110 C using inverse gas chromatography. Using the specific retention volume, V 0 g , parameters such as the Flory-Huggins polymer-solvent interaction, w 1 12 , and hard-core polymer-solvent interaction, w à 12 , and exchange parameters such as effective energy, X eff , enthalpy, X 12 and entropy, Q 12 , were determined for the solvents chosen.

Due to the presence of structural and anatomical differences that accompany anomalous kidneys, currently available endourological modalities such as SWL and PNL may be insufficient, or additional laparoscopic assistance may be required. The present study aims to evaluate the efficacy and safety of retrograde flexible ureterorenoscopic stone treatment in patients with kidney anomalies. Over the last 3 years, 25 patients with renal stones in anomalous kidneys were consecutively treated by flexible ureterorenoscopy and holmium:YAG laser lithotripsy. Among the 25 patients, fiberoptic or digital flexible ureterorenoscopies were performed for the management of horseshoe kidneys (n = 3), cross-fused ectopic kidney (n = 1), renal ectopies [n = 13; associated with pelvic (n = 6) or lumbar kidneys (n = 7)], renal malrotations (n = 4), and duplicate ureters (n = 4). For lithotripsy, 200 or 273 µm probes were used, and for stone retraction 1.3-1.9 Fr ZeroTip baskets were used. Success was defined as the complete absence of stones as evaluated with a CT scan 1 month after the operation. The mean patient age was 39.4 ± 15.75 years, and the mean stone size was 194.64 ± 103.93 mm(2) (range 50-393). Complete stone clearance was achieved in 16 patients (64%) after a single session. Seven of the patients with residual stones underwent a second session and the remaining three patients were subsequently treated with SWL. The overall complete clearance rate was 88% (22 patients) with ancillary procedures. There were no serious postoperative complications except for one case (4%) of urosepsis. Flexible ureterorenoscopy with holmium laser lithotripsy is a safe option for the treatment of renal stones in anomalous kidneys with satisfactory success rates.

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The novel 4-(3-tert-butyl-4-hydroxyanisole)]­phthalonitrile and its peripherally tetra substituted zinc phthalocyanine complex [2,9(10),16(17),23(24)-tetrakis­(4-(3-tert-butyl-4-hydroxyanisole) phthalocyaninato]­zinc­(II) (ZnPc) were synthesized and characterized by elemental and spectroscopic analysis techniques. The inverse gas chromatography (IGC) method was used to obtain secondary transition, surface properties, and thermodynamic interaction parameters of the phthalocyanine glass. Phthalocyanine selectivity was investigated using the acetate and alcohol isomers by IGC method at temperatures between 313.2 and 423.2 K. The secondary transition temperature was obtained by IGC method and differential scanning calorimetry (DSC). The dispersive component of the surface free energy, γS D, of adsorbent surface was calculated in the infinite dilution region. The specific enthalpy of adsorption, ΔH A S, the specific free energy of adsorption, ΔG A S and the specific entropy of adsorption, ΔS A S of solvents on ZnPc were determined. The acidic K A and the basic K D parameters of the ZnPc surface were calculated. The values obtained for K A and K D parameters indicated that the ZnPc surface has a basic character. The specific retention volume, V g 0, Flory–Huggins interaction parameter, χ12 ∞, equation-of-state interaction parameter, χ12 *, weight fraction activity coefficient, Ω1 ∞, and effective exchange energy parameter, X eff of ZnPc were determined. Then, the partial molar heat of sorption, ΔH 1,s and partial molar heat of mixing, ΔH 1 ∞, at infinite dilution were determined.

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