White Light and Multicolor Emission Tuning in Triply Doped Yb3+/Tm3+/Er3+ Novel Fluoro-phosphate Transparent Glass-ceramics

New Yb3+, Er3+ and Tm3+ doped fluoro-phosphate glasses belonging to the system NaPO3–YF3–BaF2–CaF2 and containing up to 10 wt% of rare-earth ion fluorides were prepared and characterized by differential scanning calorimetry, absorption spectroscopy and up-conversion emission spectroscopy under excitation with a 975 nm laser diode. Transparent and homogeneous glass-ceramics have been reproducibly obtained with a view to manage the red, green and blue emission bands and generate white light. X-ray diffraction as well as electron microscopy techniques have confirmed the formation of fluorite-type cubic nanocrystals at the beginning of the crystallization process while complex nanocrystalline phases are formed after a longer heat-treatment. The prepared glass-ceramics exhibit high optical transparency even after 170 h of thermal treatment. An improvement of up-conversion emission intensity – from 10 to 160 times larger – was measured in the glass-ceramics when compared to the parent glass, suggesting an important incorporation of the rare-earth ions into the crystalline phase(s). The involved mechanisms and lifetime were described in detail as a function of heat-treatment time. Finally, a large range of designable color rendering (from orange to turquoise through white) can be observed in these materials by controlling the laser excitation power and the crystallization rate.

Notes on turquois in the East / by Berthold Laufer --

v.13:no.1(1913)

[Calligraphic specimen, early to mid 18th century].

Exquisite album of calligraphy (muraqqaʻ or murakkaa) comprising kıt'alar employing ḥadīth of the Prophet executed by the celebrated Ottoman calligrapher Eğrikapılı Mehmet Râsim Efendi (d.1756), renowned student of Seyyid Abdullah of Yedikule (d.1731).

Pierced Jug with Harpies and Sphinxes

Metalwork, Iran, Seljuk; 8 3/16 in.x 6 39/64 in.; stonepaste; openwork, underglaze-painted, glazed in transparent turquoise

Frieze Tile

Tiles, Iran, Ilkhanid; 10 3/4 in.x 1 ft. 1 17/64 in.x 1 9/64 in.; stonepaste; molded, inglaze painted in blue and turquoise, luster-painted on opaque white glaze

Necklace Elements

H: 2 7/8 in (lg. medallion); 1 47/64 in. (half-medallion); 3/4 in.x 33/64 in. (cartouches); gold sheet; worked, chased, and set with turquoise, gray chalcedony, and glass

Tile with Image of Phoenix: detail

Tiles, Iran, Ilkhanid; 1 ft. 2 49/64 in. x 1 ft. 2 1/4 in.; stonepaste; modeled, underglaze painted in blue and turquoise, luster-painted on opaque white ground

The miracle, and other poems /

Bound in deep turquoise blue cloth over boards; stamped in gold on front cover and spine; top edge gilt.

Traité des pierres de Théophraste, traduit du Grec;

Head pieces; initials.

Hāẕā Kitāb-i Khvājah Ḥāfiẓ-i Shīrāzī, [1280, i.e. 1863 or 1864].

Richly elegant copy of the Dīvān of the masterful poet Ḥāfiẓ (Khvājah Shams al-Dīn Muḥammad Shīrāzī, d.1390?).

Around the Origin of the Images in the Veintena Section of the "Primeros Memoriales" by fray Bernardino de Sahagún

By examining the pictorial content of the veintena section of the Primeros Memoriales, the manusctipt compiled by fray Bernardino de Sahagún, I identify new pieces of evidence on the origin of these illustrations and their authors. A carefull analisis of this material suggests that it is strongly embedded in the pre-Hispanic tradition and that it is doubtful that their iconographic sources originated in Tepeopolco, as it is widely believed.