Lead-Free High Refractive Index Glasses Produced from Local Raw Materials

Many difference useful and decorative articles have been made from glasses over the centuries, especially lead-containing glasses. Due to harmful effects of lead from glass fabrication process on human beings and considering the health as well as the environmental issues, many researchers tried to produce leadless glasses using some heavy chemical elements such as barium, bismuth and zirconium. Nowadays, barium compounds seemed to be satisfactory and to be able to increase the refractive index. For production of high quality crystal glasses with high refractive index in Thailand, most raw materials including high quality sand have been imported. Because, Thailand, in fact, is rich in many kinds of raw materials for glass manufacturing, therefore, this work is set up to study the fabrication of the lead-free high refractive index glasses using local sand and barite as the main raw materials. After complete melting, the physical and optical properties of the prepared glass samples were determined to compare these properties with those of glasses prepared from foreign sand. It was found that the prepared glasses produced from local raw materials were suitably for restoration, decoration, radiation shielding, as well as glass jewelry. These glasses can be considered as one of the environmental friendly materials.

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Study of Metal Coating on Lead-Free High Refractive Index Glass Prepared from Local Sand

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.2447 ◽

2007 ◽

Vol 561-565 ◽

pp. 2447-2450 ◽

Cited By ~ 2

Author(s):

Pisutti Dararutana ◽

Narin Sirikulrat

Keyword(s):

Refractive Index ◽

Raw Materials ◽

Glass Production ◽

High Refractive Index ◽

Knoop Hardness ◽

Lead Free ◽

Lead Glass ◽

Interfacial Layers ◽

Long Time ◽

Lead Metal

Lead-containing glasses coated with lead metal have been used for decoration in Thailand for a long time, were a high refractive index glass. Due to harmful effects of lead, time degradation of glass and because of many kinds of local raw materials for glass production especially sand, colorless lead-free high refractive index glasses were prepared by using local raw materials. In this work, the various kinds of metals; silver and aluminum, were coated on the surface of the prepared glasses using both chemical and physical methods. The joining interfacial layer between the glass body and the coated layer was studied using a scanning electron microscope and the hardness of the coated glasses was measured by a microhardness tester to compare with those of lead coating. It was found that the structures between the joining interfacial layers were similar. The values of the Knoop hardness were approximately 520±20 kg/mm2. This glass can be used to replace the lead glass for restoration glass or decoration onto the surface of the new wood or the metal carving products.

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Radiation Shielding Lead-Free Glass Based on Barium-Bearing Glass Using Thailand Quartz Sands

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.214.207 ◽

2011 ◽

Vol 214 ◽

pp. 207-211

Author(s):

Krit Won-In ◽

Narin Sirikulrat ◽

Pisutti Dararutana

Keyword(s):

Refractive Index ◽

High Refractive Index ◽

Radiation Shielding ◽

Lead Free ◽

Maximum Temperature ◽

Lead Glass ◽

Attenuation Coefficients ◽

Lead Compounds ◽

Quartz Sands ◽

Free Glass

Lead glass that shows a high refractive index is the best known and most popular for radiation shielding glass. Due to the toxic of lead compounds on the human organisms as well as the environmental issues, lead free glass was fabricated by using some heavy elements such as barium and bismuth to replace lead. In this study, colorless lead free glass samples were prepared from 40 wt% local quartz sand and various concentration of BaCO3 (20-40 wt%) as the main compositions in order to study radiation shielding property. The glass mixtures were melted conventionally using electric furnace at the maximum temperature of 1250°C with 4 hr dwelling time. The gamma attenuation characteristics were studied for the photon energy of 662 keV from Cs-137. Density and refractive index were also determined. It was found that a variation of prepared glass samples can be produced both in terms of clarity and radiation shielding properties. The attenuation coefficients were linearly increased as the increase of BaCO3 content. The density and refractive index were also increased. The linear and mass attenuation coefficients of the glass sample containing 40 wt% BaCO3 were 0.234 cm-1 and 0.0726 cm2g-1. In conclusion, a low density glass samples will give rise less attenuation than a high density ones. It can be concluded that the lead-free high refractive index glass that is one of the environmental materials can be used as the gamma radiation shielding glass.

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Comparative study of solution concentration variations for polymer optical fibers sensor

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v16n2.1451 ◽

2020 ◽

Vol 16 (2) ◽

pp. 140-144

Author(s):

Hazura Haroon ◽

Muhamad Naeem Mohd Nazri ◽

Siti Khadijah Idris ◽

Hanim Abdul Razak ◽

Anis Suhaila Mohd Zain ◽

...

Keyword(s):

Refractive Index ◽

Comparative Study ◽

Output Power ◽

Optical Fibers ◽

Refractive Index Change ◽

Solution Concentration ◽

High Refractive Index ◽

Fiber Optic Sensors ◽

Polymer Optical Fibers ◽

Set Up

In this paper, we report a comparative study of fiber optic sensors for the application of aqueous solutions concentration monitoring. A simple, economical, and efficient set-up for liquid concentration measurement system was developed using polymer optical fibers (POFs). Cornstarch, sucrose, and salt solutions with different concentrations were tested, and the output power and the refractive index obtained were compared. The sensitivity of the sensor is found ranging from 0.938 μW/ RIU to 96.9 μW/RIU in term of refractive index change and 0.04298 μW/molL-1 to 0.097 μW/molL-1 in terms of concentration. It has been found that the concentration is proportionally related to its refractive index where high refractive index will experience greater loss since the light rays tend to be refracted out of the fiber instead of being internally reflected. The experimental results also show that as the solution’s concentration increases, the output power decreases.

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Properties of Lead–Free High Refractive Index Barium-Based Glass Doped with TiO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.228-229.634 ◽

2011 ◽

Vol 228-229 ◽

pp. 634-638

Author(s):

Krit Won-In ◽

Pisutti Dararutana

Keyword(s):

Refractive Index ◽

Barium Carbonate ◽

Glass Structure ◽

Amorphous State ◽

High Refractive Index ◽

Lead Free ◽

Optical And Electrical Properties ◽

Tio2 Content ◽

X Ray ◽

Lcr Meter

The effect of varying the TiO2–content on the lead-free high refractive index glass based on 25 wt% barium carbonate added in replacing lead oxide was prepared and its physical, optical, and electrical properties were investigated. Seven glass samples were synthesized and characterized by using an analytical balance, a refractometer, a LCR meter and an X-ray diffractometer. Specific gravity, refractive index, and dielectric constant increased linearly as the increasing of the TiO2-content. The amorphous state of modification of glass structure due to TiO2 addition was confirmed.

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Study of Metal Coating on Lead-Free High Refractive Index Glass Prepared from Local Sand

Materials Science Forum - PRICM 6 ◽

10.4028/0-87849-462-6.2447 ◽

2007 ◽

pp. 2447-2450 ◽

Cited By ~ 2

Author(s):

Pisutti Dararutana ◽

Narin Sirikulrat

Keyword(s):

Refractive Index ◽

High Refractive Index ◽

Metal Coating ◽

Lead Free

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A New Mounting Medium of High Refractive Index

Scientific American ◽

10.1038/scientificamerican02131886-8429csupp ◽

1886 ◽

Vol 21 (528supp) ◽

pp. 8429-8430

Keyword(s):

Refractive Index ◽

High Refractive Index

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Feminist Perspective in Shashi Deshpande's “That Long Silence”

SMART MOVES JOURNAL IJELLH ◽

10.24113/ijellh.v6i1.3579 ◽

2018 ◽

Vol 6 (1) ◽

pp. 8

Author(s):

Mohammad Ahashan ◽

Dr. Sapna Tiwari

Keyword(s):

Gender Equity ◽

Social Life ◽

Fundamental Rights ◽

Feminist Movement ◽

Human Beings ◽

Simone De Beauvoir ◽

Equal Rights ◽

And Gender ◽

Set Up ◽

Key Aspects

Man has always tried to determine and tamper the image of woman and especially her identity is manipulated and orchestrated. Whenever a woman is spoken of, it is always in the relation to man; she is presented as a wife , mother, daughter and even as a lover but never as a woman a human being- a separate entity. Her entire life is idealized and her fundamental rights and especially her behaviour is engineered by the adherents of patriarchal society. Commenting on the Man-woman relationship in a marital bond Simone de Beauvoir wrote in her epoch-making book entitled The Second Sex(1949): "It has been said that marriage diminishes man, which is often true , but almost always it annihilates women". Feminist movement advocates the equal rights and equal opportunities for women. The true spirit of feminism is into look at women and men as human beings. There should not be gender bias or discrimination in familial and social life. To secure gender justice and gender equity is the key aspects of feminist movement. In India, women writers have come forward to voice their feminist approach to life and the patriarchal family set up. They believe that the very notion of gender is not only biotic and biologic episode but it has a social construction.

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Accelerated Discovery of High-Refractive-Index Polyimides via First-Principles Molecular Modeling, Virtual High-Throughput Screening, and Data Mining

10.26434/chemrxiv.7670903.v1 ◽

2019 ◽

Author(s):

Mohammad Atif Faiz Afzal ◽

Mojtaba Haghighatlari ◽

Sai Prasad Ganesh ◽

Chong Cheng ◽

Johannes Hachmann

Keyword(s):

Data Mining ◽

Refractive Index ◽

High Throughput ◽

First Principles ◽

High Throughput Screening ◽

Large Scale ◽

Computational Study ◽

High Refractive Index ◽

Structural Features ◽

Learning Program

<div>We present a high-throughput computational study to identify novel polyimides (PIs) with exceptional refractive index (RI) values for use as optic or optoelectronic materials. Our study utilizes an RI prediction protocol based on a combination of first-principles and data modeling developed in previous work, which we employ on a large-scale PI candidate library generated with the ChemLG code. We deploy the virtual screening software ChemHTPS to automate the assessment of this extensive pool of PI structures in order to determine the performance potential of each candidate. This rapid and efficient approach yields a number of highly promising leads compounds. Using the data mining and machine learning program package ChemML, we analyze the top candidates with respect to prevalent structural features and feature combinations that distinguish them from less promising ones. In particular, we explore the utility of various strategies that introduce highly polarizable moieties into the PI backbone to increase its RI yield. The derived insights provide a foundation for rational and targeted design that goes beyond traditional trial-and-error searches.</div>

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TECHNOLOGICAL ASPECTS OF HIGH QUALITY RAW MATERIAL OBTAINING FOR PECTIN PRODUCTION

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2019/6/47-50 ◽

1970 ◽

pp. 47-50

Author(s):

I. A. Ilina ◽

I. A. Machneva ◽

E. S. Bakun

Keyword(s):

Raw Materials ◽

Thermal Characteristics ◽

Environmental Safety ◽

Raw Material ◽

High Quality ◽

Temperature Conductivity ◽

Drying Temperature ◽

Plant Raw Materials ◽

Gel Forming Ability

The article is devoted to the study of the chemical composition, physical and thermal-pfysical characteristics of damp apple pomaces and the identifying patterns of influence of drying temperature the functional composition and gel-forming ability of pectin. The research is aimed at obtaining initial data for the subsequent calculation of the main technological, hydro-mechanical, thermal, structural and economic characteristics of devices for drying the plant raw materials, ensuring the environmental safety and high quality of pectin-containing raw materials, the reducing heat and energy costs. As a result of the study of the thermal characteristics of apple pomaces, the critical points (temperature conductivity – 16.5 x 10-8 m2/s, thermal conductivity – 0.28 W/m K, heat capacity – 1627 j/(kg K)) at a humidity of 56 % are determined, which characterizing the transition from the extraction of weakly bound moisture to the extraction of moisture with strong bonds (colloidal, adsorption). It was found that the pomaces obtained from apples of late ripening have a higher content of solids (21-23 %), soluble pectin and protopectin (2.5-4.5 %). Dried pomaces obtained from apple varieties of late ripening contain up to 25 % pectin, which allow us to recommend them as a source of raw materials for the production of pectin. The optimum modes of preliminary washing of raw materials are offered, allowing to the remove the ballast substances as much as possible. It is established that when the drying temperature increases, the destructive processes are catalyzed: the strength of the pectin jelly and the uronide component and the degree of pectin esterification are reduced. The optimum drying temperature of damp apple pomaces is 80 0C, at which the quality of pectin extracted from the dried raw materials is maintained as much as possible. It is shown that the most effective for the pectin production is a fraction with a particle size of 3-5 mm, which allow us to extract up to 71 % of pectin from raw materials.

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