On the synthesis and characterization of lanthanide metal-organic frameworks

In this study, lanthanide metal-organic frameworks Ln(BTC)(DMF)2(H2O) (LnMOFs) are synthesized using the metal nitrates as lanthanide (Ln = La, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb and Lu) source and 1,3,5-benzenetricarboxylic acid (BTC) as a coordination ligand. X-ray diffraction (XRD) analysis, Fourier-transform infrared spectroscopy (FTIR), thermogravimetric (TG/DTG) analysis fluorescence spectroscopy (FLS), and scanning electron microscopy (SEM) are employed to characterize the newly synthesized LnMOFs

Kalcio acetilacetonatas - nauja pradinė medžiaga zolių-gelių metodu sintetinant Ca10(PO4)6(OH)2

Calcium hydroxyapatite Ca10(PO4)6(OH)2, HA) has been synthesized by a new non-aqueous sol-gel process based on calcium acetylacetonate and different phosphoms compounds as starting materials. The samples of Ca10(PO4)6(OH)2 were obtained by calcination of the precursor gels for 15 h at 1000 °C. The phase transformations, composition and micro-structural features of the polycrystalline samples were studied by mfrared (IR) spectroscopy and X-ray powder diffraction (XRD) analysis. The influence of the nature of phosphorus precursor on the formation of HA at 1000 °C is also discussed

Study of the red iron paints for rubrics and miniatures: accelerated aging and analytical data

In this study, the red iron paints used in ancient manuscripts for rubrics and miniatures were fabricated and investigated. The commercial three different iron pigments (red ochre (Fe2O3), red bolus (Fe2O3.xSiO2.yAl2O3), and hematite (Fe2O3)) and three binding media (gum Arabic, fish glue and parchment glue) were used for the preparation of analogous to historical red iron paints. The obtained model red iron paints were analyzed with the aim to create a short data library which could be used for the characterization of different model compositions of red paints as well as real historical and archaeological red paints. The obtained red paints and binding media were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD) analysis and thermal (TG/DSC) analysis techniques. The accelerated aging test was also applied for the analogous to historical red iron paints. These results are useful to develop red paint guidelines for the storage and display for improved conservation and accessibility of manuscripts

Sol-Gel Synthesis and Characterization of Selected Transition Metal Nano-Ferrites

In the present work, the sinterability and formation of nanosized yttrium iron garnet (Y₃Fe₅O₁₂), yttrium perovskite ferrite (YFeO₃),cobalt, nickel and zinc iron spinel (CoFe₂O₄, NiFe₂O₄and ZnFe₂O₄, respectively) powders by an aqueous sol-gel processes are investigated. The metal ions, generated by dissolving starting materials of transition metals in the diluted acetic acid were complexed by 1,2-ethanediol to obtain the precursors for the transition metal ferrite ceramics. The phase purity of synthesized nano-compounds was characterized by infrared spectroscopy (IR) and powder X-ray diffraction analysis (XRD). The microstructural evolution and morphological features of obtained transition metal ferrites were studied by scanning electron microscopy (SEM).<p><a href="http://dx.doi.org/10.5755/j01.ms.17.3.598">http://dx.doi.org/10.5755/j01.ms.17.3.598</a></p

Silver nanoprisms self-assembly on differently functionalized silica surface

In this work colloidal silica/silver nanoprisms (NPRs) composite coatings were made. Firstly colloidal silica sols were synthesized by sol-gel method and produced coatings on glass by dip-coating technique. Next coatings were silanized by (3-Aminopropyl)triethoxysilane (APTES), N-[3-(Trimethoxysilyl)propyl]ethylenediamine (AEAPTMS), (3-Mercaptopropyl)trimethoxysilane (MPTMS. Silver NPRs where synthesized via seed-mediated method and high yield of 94 ±15 nm average edge length silver NPRs were obtained with surface plasmon resonance peak at 921 nm. Silica-Silver NPRs composite coatings obtained by self-assembly on silica coated-functionalized surface. In order to find the most appropriate silanization way for Silver NPRs self-assembly, the composite coatings were characterized by scanning electron microscopy (SEM), dynamic light scattering (DLS), water contact angle (CA) and surface free energy (SFE) methods. Results have showed that surface functionalization is necessary to achieve self-assembled Ag NPRs layer. MPTMS silanized coatings resulted sparse distribution of Ag NPRs. Most homogeneous, even distribution composite coatings obtained on APTES functionalized silica coatings, while AEAPTMS induced strong aggregation of Silver NPRs

Sintezės temperatūros įtaka T3Sc2Ga3O12 granato, sintetinto skirtingais metodais, faziniam grynumui, kristališkumui bei optinėms savybėms

Mixed-metal garnet (Y3Sc2Ga3O12, YSGG) samples were prepared by: (i) sol– gel, (ii) semi–sol–gel, and (iii) solid state reaction methods. In all the cases, precursor powders were calcined for 10 h at 800 °C in air, ground in an agate mortar and heated again for 10 h at different temperatures in the range of 1000–1400 °C in air atmosphere. The synthesized samples were characterized by X-ray powder diffraction analysis and scanning electron microscopy. It was demonstrated that monophasic Y3Sc2Ga3O12 garnet could be obtained at 1000 °C using the sol–gel technique and at 1200 °C using the semi–sol–gel route