scholarly journals A technological study on the 17th century raised gilded substrates in three royal palaces of Isfahan, Iran

2013 ◽  
Vol 1 (1) ◽  
pp. 21 ◽  
Author(s):  
Parviz Holakooei ◽  
Abbas Abed-Esfahani ◽  
Samad Samanian ◽  
Hesam Aslani

The raised substrates of gilding decorations, called lāyachīnīī in Persian, were widely used throughout the Safavid period (1501-1736 AD) in Iran. This paper presents the first analytical data obtained from the lāyachīnīs of three seventeenth century royal Safavid buildings (ʿAlī- Qāpū, Chihil-Sutūn, and Hasht-Bihisht) in Isfahan, Iran, using energy dispersive X-ray spectroscopy, scanning electron microscope, Xray powder diffraction, and thin layer chromatography. According to the analytical data, different forms of calcium sulfate (dihydrate, β-hemihydrate, and anhydrite), the red iron oxides, and a proteinaceous binder (probably animal glue) are the main constituents of the raised lāyachīnī substrates. The results show that a dry mixture of the plaster of Paris and the red iron oxides are mixed with diluted animal glue to obtain a slurry to be applied in several layers, one top of the another, to achieve the raised substrates. This technique is similar to those European raised pastiglia substrates although the method of the preparation in the Persian technique is different from the European one.

2018 ◽  
Vol 7 (2) ◽  
pp. 139-146 ◽  
Author(s):  
Nuchnapa Tangboriboon ◽  
Wanitcha Unjan ◽  
Watchara Sangwan ◽  
Anuvat Sirivat

AbstractCalcium sulfate dihydrate (CaSO4·2H2O) was prepared from the chemical reaction between calcium carbonate from duck eggshell and sulfuric acid at 25°C. The CaSO4·2H2O was dried in an oven at 110°C and transformed into calcium sulfate hemihydrate or plaster of Paris (CaSO4·0.5H2O). The CaSO4·0.5H2O was calcined at 700, 800 and 900°C and transformed into anhydrite or anhydrous calcium sulfate (CaSO4). The raw material used in this research was the duck eggshell, the waste eggshell generated from food processing industries. The obtained anhydrous calcium sulfate or anhydrite has true density, color, specific surface area, pore diameter and particle size equal to 2.95 g/cm3, white powder, 3.57 m2/g, 96.98 Å and 3.983 μm, respectively. In addition, other characteristics, microstructures, phase transformation and physical properties of raw materials and calcium sulfates were investigated and reported here using X-ray fluorescencemeter, Fourier transform infrared spectrometer, differential thermal analyzer, thermogravimetric analysis, scanning electron microscope, X-ray diffractometer, pycnometer method and Brunauer-Emmett-Teller.


2019 ◽  
Author(s):  
Hendra Himawan ◽  
Ulil Albab Taufiq ◽  
Rudi Setiawan ◽  
Masturi . ◽  
Susilo . ◽  
...  

Calcium Sulfate Dyhidrate/gypsum is a material commonly found in nature which is used at industrial site for making a wall, roof, etc. One of the problems found in material industry is crack deffect, white crack defects is very difficult be identified it visibility. Radiography Non-Destructive Test (RNDT) is non destructive test supported by digital radiographic producing digital image. This work aims to determine the gypsum properties to find out crack defect using RNDT. Radiographic image depends on exposure factors (kV, mA, s, and SID). Digital image can be proceed using OctaveGUI to determine the crack defect area, image processing using Prewitt detection. Radiographicdigitalresultof3gypsumboards(a,bandc)and2gypsumprofilsamples (d and e) were found the crack on each samples. RNDT was perfomed using X-ray voltageat60kVona,b,c,d,andesamples.Eachsamplescrackareavalueare158.13 mm2; 127.43 mm2; 196.81 mm2; 73.97 mm2; dan 18.80 mm2. Others RNDT was using X-ray voltage at 70 kV on samples a, b, c, d, and e. Each samples crack area value are 220.62 mm2; 1,711.57 mm2; 209.33 mm2; 76.50 mm2; dan 11.18 mm2. In conlusion, the crack area values obtained can be used as RNDT.


TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.


2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Ryosuke Sinmyo ◽  
Elena Bykova ◽  
Sergey V. Ovsyannikov ◽  
Catherine McCammon ◽  
Ilya Kupenko ◽  
...  

Abstract Iron oxides are fundamentally important compounds for basic and applied sciences as well as in numerous industrial applications. In this work we report the synthesis and investigation of a new binary iron oxide with the hitherto unknown stoichiometry of Fe7O9. This new oxide was synthesized at high-pressure high-temperature (HP-HT) conditions, and its black single crystals were successfully recovered at ambient conditions. By means of single crystal X-ray diffraction we determined that Fe7O9 adopts a monoclinic C2/m lattice with the most distorted crystal structure among the binary iron oxides known to date. The synthesis of Fe7O9 opens a new portal to exotic iron-rich (M,Fe)7O9 oxides with unusual stoichiometry and distorted crystal structures. Moreover, the crystal structure and phase relations of such new iron oxide groups may provide new insight into the cycling of volatiles in the Earth’s interior.


2005 ◽  
Vol 5 (1) ◽  
pp. 1-23
Author(s):  
Anabella Tulin ◽  

The characteristics and properties of interlayer materials from 10 non-allophanic (Melanudand) and red yellow soils (Alfisols and Ultisols) from three locations in Japan were studied by chemical extractions and x-ray diffraction (XRD) analyses. Allophane was dissolved from clay samples using 0.15 M acid oxalate solution while silicon and aluminum were dissolved using both 0.15 M acid oxalate and 0.3 M sodium citrate solutions. XRD analyses were done for the treated and untreated samples. For the chemically extracted samples, the clay samples were treated with bicarbonate citrate solution for the removal of iron oxides after the dissolution treatments then saturated with K and Mg ions for XRD analyses. Results of the XRD patternd of the untreated and treated samples indicated the interlayer materials as a hydroxy-interlayered form for vermiculite (HIV). Between the two dissolution treatments, the 0.3 M sodium citrate treatment was found to be more effective in removing the interlayer materials than the 0.15 M acid oxalate treatment by allowing interlayer expansion and collapse.


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