Abstract
Soda-based glass samples were fabricated in a laboratory scale using quartz sands that was a by-product of feldspar floatation in Tak Province, northern Thailand, and 25-wt% commercial-grade Na2CO3 as the main compositions. Fe2O3 of 0.1 to 10.0 wt% concentrations was doped into the glass mixture. Well-mixed and dried powders were melted in a ceramic crucible for 4 hr at 1250ºC using an electric furnace. Transparent and bubble-free glass samples were obtained as results. It was found that Fe2O3 dopant turned the otherwise colorless glass to dark brown. Dielectric property and physical properties, such as, color, specific gravity, and refractive index of the glass samples were studied. The samples’ dielectric constant, specific gravity, and refractive index increased with increasing Fe2O3 doping concentration. UV-VIS-NIR and synchrotron-based X-ray absorption spectra were measured and discussed.
Introduction
Chemical composition of glasses showed an important role in determining properties of them. Glass is ordinary contained with three main parts; network former, network modifier and intermediate species which fall somewhere between network former and modifier [1, 2]. Oxide glasses containing transition metal ions are very interesting because of their potential and wide range of applications such as switching and memory devices, transducers, insulators and dielectrics [3, 4], that are widely applied in many fields; information technology, energy and infrared detection [5]. In general, transition metal ions can exist in multivalent states depending upon the base glass composition, melting temperature and time, and pressure conditions [6]. Among these elements, prime attention should be paid to iron [7]. The addition ...
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... a superlene sample holder prior to being loaded into the sample chamber. The x-ray beam was of 1 mm x 10 mm rectangular shape. Energy calibration was achieved with Fu foil standard and the position of the first inflection point was taken at 7112 eV (±0.2 eV). Reference spectra were also collected on pyrite and hematite powders.
Results and discussion
It was found that the colors of the glass samples were changed from colorless to dark brown.
The specific gravity and refractive index were increased with increasing Fe2O3 contents, from 2.5521 to 2.6562 and 1.51 to 1.52, respectively, as detailed in Table 1 and Figure 2 (a and b).
The dielectric constant was increased with increasing Fe2O3 contents, as shown in Figure 2 (c). It was also found that the dielectric constant depend with the frequencies; the higher frequency, the lower dielectric constant.
The objective of this lab is to find the equilibrium constant of Fe(SCN)2+ through multiple trials using a spectrometer. Since one chemical is colorless and the other is colored a spectrometer can be used to monitor amounts of each in the solution. By completing multiple trials an average can be reached for the value of the equilibrium constant of Fe(SCN)2+.
GLASS written by ellen hopkins intermenes the real life struggles that teenagers face everyday, from love to drugs to destructive relationships. Ellen really hits home showing the life of a once 4.0 honors student Kristina; whose life easily got turned upside down from one toxic summer at her fathers that will show the darkest side possible of life. An estimated 12 percent of children in the United States live with a parent who is dependent on or abuses alcohol or other drugs. Based on data from 2002 through 2007, it was to be reported that 8.3 million children under the age of 18 lived with at least one substance-dependent or substance-abusing parent according to Substance Abuse and Mental Health Services Administration (Paragraph 4). The bond between a child and their parents is so pure yet
In high school and college many people who have taken chemistry may have learned that there are only four states of matter:solid, liquid, gas, and plasma. Where would glass fall within these states? Most people you ask might say it’s a solid of course. You can touch it and hit it and it will not give way to your hand. It makes up our windows and protects us from weather, so why would it not be a solid? Well surprisingly the state of glass, or the transition of melted glass to a more solid glass, seems to be a very debated subject in the science world. In fact, in Science Magazine’s 125th Anniversary issue which contained the world’s top one hundred science questions yet to be answered, question 22 was, “What is the nature of the glassy state?” and question 21 goes hand in hand, “Is superfluidity possible in a solid?”(Science,2005). Its seems as though glass is a state of its own, between liquid and solid.
The purpose of this experiment was to find the physical and chemical properties of many different substances. The physical and chemical properties of: Sulfur (S), Iron fillings (Fe), Sodium bicarbonate (NaHCO3), Sucrose (C12H22O11), Sand (SiO2), Magnesium (Mg) and Sodium chloride (NaCl) were all recored. While observations where made about: Iron fillings mixed with Sulfur with and without a magnet, Magnesium both burnt and unburnt, Magnesium (ash and unburnt) mixed with Hydrochloric acid, Sodium bicarbonate with Hydrochloric acid, burned Sucrose and its solubility, Sodium chloride mixed with sand and
0,74 0,87 1,00 0,49 100... ... middle of paper ... ... some groups had got different leakage of the pigment in the test tubes with water.
A very important compound is dialuminum oxide Al2O3. The structure of dialuminum oxide is sometimes hexagonal. The structure is .It is one of the hardest substances known. It is formed by natural occurrence. Dialuminum oxide is formed from the reaction of metallic aluminum with oxygen gas. It is a white crystalline solid. Aluminum chloride has a formula of ALCl3. The structure is . It is mainly produced in the production of aluminum metal. It is white, but samples are often contaminated with iron trichloride, giving it a yellow color. The compound formula for dialuminum sulphide is Al2S3.The structure is . It is a ...
The primary goal of this experiment was to determine which types of glassware are the most accurate and precise in measuring substances. Another goal of this experiment was to help familiarize ourselves with the different types of glassware, and how we should handle the laboratory equipment. The accuracy and precision of a particular type of glassware is important because it allows for accurate measurements when performing different experiments. It also allows us to differentiate between glassware that is better for containing substances versus glassware that can deliver substances more accurately. In order to measure the accuracy and precision of the different types of glassware, we first chose seven different types of glassware. The general
Refer to Chemistry Lab # 2 – Investigating Changes. No changes have been made in this experiment. Methods = == ==
Haynes, William M.., and David R. Lide. CRC handbook of chemistry and physics a ready-reference book of chemical and physical data : 2012-2013. 93e édition. ed. Boca Raton (Fla.): CRC Press, 2012. Print.
Four solutions were tested an out of the four only one had a color change, meaning that it had alcohol present. This solution was methanol and of course it would produce a color change because methanol is an alcohol. One solution that should have changed color was solution 4, the base-hydrolyzed aspartame, but it did not produce a color change when aqueous ceric ammonium nitrate reagent. Water and fresh aqueous aspartame are not going to produce a color change because there is no alcohol group in there structure.
The elongations-to-break of aged PHB and PHBV at 15°C decreased by 64% and 72%, respectively, after 168 days (Srubar et al., 2012). Ultimate strengths decreased by 28% and 8.9% for PHB and PHBV, respectively. During the aging process, the amorphous regions of PHB and PHBV underwent glassy aging in the rigid amorphous fraction, resulting a significant embrittlement. Over the testing period, PHB and PHBV samples had a maximum increase in modulus of 166% and 178%, and crystallinity of approximately 41% and 58%, respectively (Srubar et al.,
The purpose of this experiment is to determine the stoichiometry of a complex ion using Job’s method. In doing so, experience is gained in using the techniques and instrumentation involved in absorbance spectrophotometry.
The area under the curve represents the energy required to compensate for the thermal events of the sample. Some instruments represent endothermic processes (melting) as downward curves and exothermic processes (crystallisation) as upwards peaks, while other instruments show it in the opposite way. (18) DSC can be used to evaluate different thermal events including melting, solid-state transitions, crystallization, glass transitions … (19) DSC may therefore be used to differentiate between polymorphs according to their melting point or to examine the transformation of metastable systems. It is essential though to confirm the results of DSC with other characterization techniques such as Raman spectroscopy, IR spectroscopy and X-ray diffraction.
Fiber optics, in the world of technology, is used to carry voice, data, and video inside these strands of glass. Optical fiber for telecommunications consists of three components: core, cladding and coating. The core is the central region of an optical fiber through which light is transmitted. The core and cladding are manufactured together as a single piece of glass and cannot be separated from one another. The third section is the outer protective coating. This coating is typically an ultraviolet (UV) light-cured acrylic applied during t...
Glass blowing as a career is really unique and creative. People can learn to make all sorts of crazy things and to use their own creativity to its fullest. Glassblowing is the art of shaping melted glass to make decorative objects. It is an area of concentration within the fine arts field at colleges and universities. Glass is an adaptable, old material that is still being explored and understood by everyone from artist to scientist even in this new age.