Poly (l-lactic acid) (PLLA) and its random copolymers with small amount of d-isomer co-units but identical mass-average molar mass of 120 kDa were analyzed regarding the non-isothermal and isothermal crystallization and nucleation behaviors. First, it was confirmed that the gross crystallization...

Poly(d,l-lactide) (PDLLA) and stereocomplex-poly (l- and d-lactide) (sc-PLA) blends were prepared by solution blending. The influence of the addition of PDLLA on nonisothermal crystallization behavior of sc-PLA was investigated. It was observed that the crystallization peak temperature of PDLLA/...

A new method to calculate the d-lactide content in the intermediate for the synthesis of poly(lactic acid) (PLA) has been developed using capillary gas chromatography (GC). Separating d-lactide from l-lactide using conventional GC is challenging. However, the content of two lactide enantiomers c...

The crystallization behavior of poly(d-lactide) loaded with xylan propionate (XylPr) and xylan butyrate (XylBu) was investigated. Non-isothermal crystallization study revealed that the crystallization temperature (Tc) of PDLA decreased by almost 30 °C when loaded with 1% XylPr or XylBu. PDLA bl...

An analytical method has been proposed to quantify the D-lactide content in a lactide stereoisomeric mixture using combined gas chromatography and polarimetry (GC- polarimetry). As for a lactide stereoisomeric mixture, meso-lactide can be determined quantitatively using GC, but D- and L-lactides...

The coordination reaction of thorium (IV) with a ditopic bidentate ligand to form supramolecular polymer was studied by resonance light scattering (RLS) spectra, second-order scattering (SOS) spectra and frequency-doubling scattering (FDS) spectra, respectively. The ditopic bidentate ligand is i...

A novel green supramolecular solvent-based liquid-liquid microextraction (SsLLME) method was developed and validated for preconcentration of thorium(IV) in various environmental samples. The presented preconcentration method was based on using 1-decanol/THF as supramolecular solvent phase and qu...

A calixarene derivative, 5,11,17,23-tetra(diethoxyphosphoryl)-25,26,27,28-tetraacetoxycalix[4]arene (L), was studied for the extraction and separation of thorium and rare earths in nitrate medium. Thorium was extracted into the organic phase by a complex of Th(NO3)4·L with the logarithm of the ...

A validated spectrophotometric method has been described for the determination of thorium(IV) in synthetic mixture and soil samples. The method is based on the complexation of thorium(IV) with rifampicin at room temperature which absorbs maximally at 525 nm. Beer's law is obeyed in the conc...

The solubility of uranium and thorium has been measured under the conditions anticipated in a cementitious, geological disposal facility for low and intermediate level radioactive waste. Similar solubilities were obtained for thorium in all media, comprising NaOH, Ca(OH)2 and water equilibrated ...

In this study an MEKC method has been developed and applied for the analysis of thorium and uranium from environmental samples. Copper, nickel, cobalt, and iron present in the matrix were analyzed concurrently. The method is based on pre-capillary chelation of analyte with bis(salicylaldehyde) e...

A rapid and sensitive spectrophotometric method has been developed for the determination of Th4+ ions using tetra butyl 2,2′-bipyridine-5,5′-diylbis(methylene) diphosphonate (L) as a chemosensor. The selective complexation of L was examined with various f-metal ions like Th4+, U6+ and Ln'...

Some mixed-ligand thorium(IV) complexes with the general formula [Th(OOCCH3)4−nLn] (L = anions of myristic, palmitic or stearic acid and n = 1–4) have been synthesized by the stepwise substitution of acetate ions of thorium(IV) acetate with straight chain carboxylic acids in toluene under reflu...

The adsorptive capability of rice-husk for the sorption of thorium ions from aqueous solutions in batch mode was studied. The key process variables (initial metal ion concentration, initial solution pH and S/L (solid-to-liquid ratio) were optimized for achieving maximum bioremoval efficiency (B%...

The citrate gel process was used to synthesize ultrafine-grained, amorphous and crystalline Dy3Fe5O12 (dysprosium iron garnet, DyIG). The citrate precursor is obtained on drying the citrate gel at 110°C and has the chemical composition Dy3Fe5(Cit)25·36H2O. The thermal decomposition of the hydr...

This paper reviews the development course of separating rare earths with acid phosphorus extractants, including extraction chemistry (thermodynamics and kinetics), separation process and industrial application, the loss/degradation of extractants, etc.

This work investigates the use of leaching with malic and citric acids for the recovery of neodymium (Nd) from the NdFeB permanent magnets of discarded hard disk drives (HDDs). Evaluation was made of the effect of previous roasting of NdFeB powder on the recovery of Nd. The HDDs were manually di...

This paper deals with synthesis and characterization of novel γ-Fe2O3-NH4[email protected]2(APTMS) nanoparticles formed from magnetic γ-Fe2O3 core, stabilized electrostatically in basic media NH4OH, doped with SiO2 shell and functionalized with 3-aminopropyltrimethoxysilane. The gradually synt...

Samarium substituted lithium manganese oxide powders were successfully prepared by molten-salt synthesis (MSS) using eutectic mixture of LiCl, SmCl3·6H2O and MnO2 salt at 700 °C. The synthesis was carried out in open atmosphere. The crystalline powders were characterized for their phase identi...

Understanding of the metallurgical behaviour of indium is dependent on an accurate appraisal of the mineralogical site of the element in a given ore or concentrate. The dominant indium-bearing mineral in (Pb)–Zn ores and concentrates is sphalerite. Indium is substituted within the crystal latti...