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This study focusses on the spectroscopic observation of marbles, rubies and the transition zone between ruby and its hosted marble that may distinguish the origin of ruby. Samples of ruby-bearing marble were obtained from Afghanistan, Myanmar, and Pakistan. Energy-dispersive X-ray fluorescence was used to analyze the chemical compositions. Although the content of other elements in the marble varied with the origin, the Cl content was quite constant. A diagram of the trace elements Fe and Ga was used to determine the origins of the marble-hosted rubies. X-ray diffraction was used to verify the structure phases, where trioctahedral mica, plagioclase, quartz, and alkali feldspar were found in marbles. Ultraviolet–visible spectrophotometry was used for rubies, where a 659 nm fluoresce peak was found in the Myanmar ruby sample, which could make Myanmar ruby redder and more sought after. The bonding of elements and inclusions of the samples were analyzed using Fourier transform infrared spectroscopy, Raman spectroscopy, and photoluminescence. A FTIR peak at 630 cm−1 is found to be useful in judging the temperature of ruby formation. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were used to analyze the variation of the transition zone, which revealed that the boundary was a gradation zone. Concentrations of Al203 increased in this zone, but CaCO3 concentrations decreased. [ABSTRACT FROM AUTHOR]

This study examined the effects of low-temperature heat treatment on the characteristics of the rubies from Mong Hsu, Myanmar. Five ruby samples were heated to 400, 600, 900 and 1200 °C for different durations, respectively. Before and after each heating step, a visual examination was conducted with a gem microscope under different illumination conditions. Various spectral analyses such as UV-Vis, FTIR, Raman and PL were also used to examine the effect of heating on the ruby samples. The low-temperature heat treatment enhanced the ruby samples by causing the dark blue core to partially or completely fade away. It then increased the overall light transmittance and enhanced the fluorescence peak around 694 nm but did not improve the red hue of the samples. Two major changes were found in the experiments. One was the dark blue core of the samples that faded as the heating temperature increased. They were verified by the spectra to be the variation in the intervalence charge transfer between Fe2+ and Ti4+. The variation in the intervalence charge transfer of Mong Hsu ruby was not noticeable before heating to 900 °C but changed dramatically when heated to 1200 °C. The other was the shift of the FTIR peak, which is caused by decomposition of minerals due to heating. An FTIR 630 cm−1 peak proved to be sensitive to the low-temperature heating and might be helpful for detecting low-temperature treatment. [ABSTRACT FROM AUTHOR]

Cement manufacturing is one of the highest carbon dioxide emission industries. It releases 880 kg carbon dioxide for every ton of cement produced. In Taiwan, the carbon dioxide emission from cement industry is more than 10 million tons per year. The development of low carbon dioxide emission green cement can be a solution to replace part of OPC for civil applications and reduce carbon dioxide emission. Geopolymer consists of a polymeric Si–O–Al framework, similar to zeolites which can be formed by mixing aluminosilicate materials, sodium hydroxide and sodium silicates. Geopolymers have advantage of high compressive strength, fire resistance, low shrinkage, acid resistance and low thermal conductivity. In this study, marble-based geopolymer was studied by mixing marble powder, blast furnace slag (BFS) and alkali solution. Physical/mechanical properties of marble-based geopolymer prepared with different marble/BFS weight ratio and SiO2/Na2O mole ratio were tested. The experimental results indicated that the compressive strength of marble-based geopolymer can reach 44 MPa within 120 minutes setting time. The microstructure of geopolymeric green cement contains C-S-H gel and aluminosilicate in the framework. According to the experiment results, marble-based geopolymer has the potential to be used as a new civil engineering construction material.

The objective of this study is to recover SiC from silicon wafer cutting slurry using physical separation and acid/alkali purification processes. Hydrocyclone was used in the first-stage process to recover SiC and Si from silicon wafer cutting slurry. Through hydrocyclone separation, the SiC content and recovery of can reach 98 and 88%, respectively. In acid and alkali purification processes, the iron and silicon can be removed and further increase the SiC content up to 99.5%. From the test results obtained in this study, it is believed that the recycling and reutilization of SiC from silicon wafer cutting slurry can be highly feasible and economical. [ABSTRACT FROM AUTHOR]

In this study, the fabrication of nano-silver doped activated coir charcoal particles (ACC@Ag) was proposed using chemical reduction method. Certain amount of ACC@Ag was added into the spinning solution after de-foaming process to fabricate viscose rayon staple fibers using wet spinning method. The 1.25 denier × 38 mm viscose rayon/ACC@Ag staple fibers was then blended with 1.5 denier × 1.5 in. polyester staple fibers to fabricate PET/rayon/ACC@Ag with 50%/50% blending ratio and 30 s and 40 s linear density using ring spinning process. The blended yarns are expected to be used for the fiber products with anti-bacterial, warm retention, odor absorption and anti-static properties. This ring blended yarns were then used as the raw material to fabricate woven fabrics with anti-bacterial and anti-electrostatic properties which comply with JIS and AATCC standards. The influences of woven structures, fabric constitutions on the temperature difference, anti-bacterial, odor absorption and anti-electrostatic properties of woven fabrics were also investigated. Finally, the potential applications of the woven fabrics fabricated will also be proposed and suggested in this study. [ABSTRACT FROM PUBLISHER]