Monetite Synthesis Essay - Homework for you

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Monetite Synthesis Essay

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Synthesis and Characterization of Monetite Prepared Using a Sonochemical Method in a Mixed Solvent System of Water

First online: 09 January 2013

Synthesis and Characterization of Monetite Prepared Using a Sonochemical Method in a Mixed Solvent System of Water/Ethylene Glycol/N ,N -Dimethylformamide
  • S. Baradaran Affiliated with Department of Engineering Design and Manufacture, Faculty of Engineering, University of Malaya Email author
  • . W. J. Basirun Affiliated with Department of Chemistry, Faculty of Science, University of Malaya
  • . M. R. Mahmoudian Affiliated with Department of Chemistry, Faculty of Science, University of Malaya
  • . M. Hamdi Affiliated with Center of Advanced Manufacturing and Material Processing, University of Malaya
  • . Y. Alias Affiliated with Department of Chemistry, Faculty of Science, University of Malaya

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Abstract

Bioactive monetite (anhydrous calcium hydrogen phosphate, CaHPO4 ) has been successfully synthesized using the sonochemical method in the presence of a ternary solvent system of water/ethylene glycol (EG)/N ,N -dimethylformamide (DMF). The morphology and chemical composition of the synthesized powders were characterized using field emission scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The results indicated that with increasing sonication time, the morphology changed slightly from a plate-like one to a combination of plates (flower-like). The formation of flower-like nanosheets requires an optimum time of 40 minutes, and the nanosheets have an average thickness of 210 ± 87 nm. The concentration of DMF clearly influences the morphology and crystal phase of the products. The ideal product was obtained using a water/EG DMF ratio of 1:2.

Manuscript submitted February 29, 2012.

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Monette Trumpet Mouthpieces

Monette mouthpieces are revolutionary. Since 1985, David G. Monette Corporation has been designing mouthpieces to do what no other mouthpiece has ever done: provide constant pitch center, regardless of how loud or soft, or how low or high a musician plays. This acoustical innovation improves every aspect of brass instrument performance---sound, response, intonation, and endurance. Constant pitch center designs allow brass players more freedom to devote their efforts to making music, rather than to compensating for the acoustical flaws of their equipment. The STC-1 is the standard weight model, designed for use in non-Monette instruments, and comes in either the Classic design, or the new Prana design.

Monette Prana mouthpieces may be the biggest single improvement in Monette equipment ever. Prana means the "energy of life." Appropriately named, Prana mouthpieces provide more brilliance and color in the sound, a more open, centered and effortless response, and a noticeably easier upper register! They also provide improved intonation and an overall ease of playing not found even in Classic Monette mouthpieces. If you aren't sure which configuration is right for you, click here to read further commentary on Classic and Prana Monette mouthpiece designs.

How to Select a Monette Mouthpiece
Because of the inconsistent playing qualities found in conventional mouthpiece designs, players have become accustomed to accepting compromises in mouthpiece size in order to maintain a given range and endurance in their playing. Monette mouthpieces are designed to eliminate these frustrating compromises and to promote an easier and more consistent approach to equipment selection.

Monette constant pitch center mouthpiece designs negate the old rules of choosing equipment, including how to pick the best size mouthpiece for a given musical task. One of Monette's primary goals in working with clients is to help them let go of old ideas about how they listen to themselves as they play, how they choose instruments, and how they choose mouthpiece sizes.

If brass players only had to play in the middle register and for no more than an octave in range, most players would be using a larger mouthpiece than they currently use. When choosing your first Monette mouthpiece, we generally suggest trying a size that is at least a little bit larger than you may be accustomed to. A slightly larger size in Monette equipment will actually enhance one�s upper register and fill out one�s sound because it encourages the player to play down into the center of the equipment in a way that is not possible on conventional equipment.

Not only do players find that using larger sizes is advantageous when using Monette mouthpieces, but they also find they can more easily change mouthpiece sizes for different styles of playing without suffering the usual acclimation problems.

All Monette mouthpieces come with larger throat sizes than most players of conventional mouthpieces have been accustomed to. The throat sizes for each model are optimized for each individual mouthpiece design. When larger throats are used in conventional mouthpieces, the upper register goes even flatter than it already does with traditional, mass-produced designs; with Monette constant-pitch-center designs, this is no longer an issue.

When playing Monette mouthpieces, it is essential to play without the physical adjustments we have learned to make for the inconsistent pitch center of conventional equipment. For more information, please refer to Monette's essay on Pitch Center, Body Use, and Resonance. and the Acclimation Guide .

Click here to read Norlan Bewley's excellent review of Monette mouthpieces.

Synthesis and Characterization of Nanoporous Monetite Which Can Be Applicable for Drug Carrier

Synthesis and Characterization of Nanoporous Monetite Which Can Be Applicable for Drug Carrier

Faculty of Material Science and Engineering, Iran University of Science and Technology, Narmak, Tehran 16846, Iran

Received 22 May 2012; Accepted 18 October 2012

Academic Editor: Jun Liu

Copyright © 2012 Esmael Salimi and Jafar Javadpour. This is an open access article distributed under the Creative Commons Attribution License. which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Wormhole-like mesostructured monetite was successfully synthesized using cetyltrimethylammonium bromide (C19 H42 BrN, CTAB), as a porosity agent. X-ray techniques and FTIR reveal that the crystalline grains consist of highly crystalline pure monetite phase. Monetite rods with diameter around 20–40 nm and length in the range of 50–200 nm were confirmed by FESEM and TEM. Based on N2 adsorption-desorption isotherms investigation, surface area increased up to 31.5 m 2 /g due to the removal of surfactant after calcinations at 400°C. The results indicate that CTAB can not only affect monetite crystallization but also change particles morphology from plate shape to rod-like.

1. Introduction

Monetite’s potential as a biomaterial has recently been highlighted by a series of in vitro. animal and human studies in which monetite-based biomaterials have shown promising results as bone substitutes [1 –3 ].

Monetite has a higher solubility than octacalcium phosphate, tricalcium phosphate, and calcium hydroxyapatite in aqueous solutions at the physiological pH and is considered to exhibit a high in vivo resorbability in comparison to the apatitic cements [3 ]. This high solubility has been the main stimulus for the current study.

Introduction of nano-sized pores in these materials can not only significantly enhance the total surface area but also promote adsorption of biomolecules and drugs onto the surface of the particles. It can also increase their solubility and resorbability to the high levels [4 ]. Since the formation of silicate-based mesoporous structure was reported in 1992 [5 ], it has become one of the most active research area of material science [6 –8 ]. So far, monetite particles have been synthesized via different processing routes [9. 10 ]. To our best knowledge, the synthesis of mesoporous monetite has been seldom reported in the literature. In this study, we attempt to achieve the direct crystallization of mesoporous monetite by chemical precipitation method using CTAB as a structure directing agent.

2. Experimental 2.1. Materials and Procedure

Calcium chloride (CaCl2. Merck Co) and diammonium hydrogen phosphate [KH2 PO4. Merck Co] as the Ca and P sources and CTAB as surfactant were used to synthesize nanoporous monetite powders in this study.

In a successful synthesis run to yield only single-phase CaHPO4. 4.075 g potassium dihydrogen phosphate [KH2 PO4 ] and 5 g CTAB were dissolved in 50 mL de-ionized water at room temperature with stirring for 1 hr. Subsequently, 5.55 g CaCl2 in 50 mL de-ionized water was added dropwise to the solution mixture, yielding a milky suspension, which was refluxed at 120°C for 24 h.

The pH value was adjusted to pH = 4-5. The suspension was then transferred into a 100 mL PTFE-lined autoclave and heated at 90–150°C in an oven for a specified time. The precipitate was filtered and washed several times with distilled water to remove contaminated ions and surfactant. Then, it was dried at 100°C for 24 h. Calcination of powder was carried out at different temperature (up to 550°C).

2.2. Characterization

The X-ray powder diffraction patterns were recorded on a Philips 1830 diffractometer using Cu-Kα radiation at 40 kV and 40 mA. Nitrogen adsorption-desorption isotherms of the synthesized samples were measured at 77 K on Micromeritics model ASAP 2010 sorptometer to determine pore-size distribution and surface area of the samples. Energy dispersive X-ray (EDX) element analysis was carried out on the JEOL 6300F scanning microscope. The morphology of the powders was examined by scanning (SEM, JEOL 6300F) and transmission (TEM, Philips CM120) electron microscopy. The Fourier transform infrared spectra of samples were measured on a DIGILAB FTS 7000 instrument under attenuated total reflection (ATR) mode using a diamond module. TGA (Perkin-Elmer 7 series thermal analysis system) was performed at 10°C/min from room temperature to 800°C to determine the thermal behavior of the synthesized monetite.

3. Results and Discussion

Figure 1 shows the XRD patterns of the as-dried and calcined monetite. WAXRD patterns (Figure 1 ) of the nanoparticles consist of narrow peaks with

spacing consistent with well-ordered crystalline monetite. (JCPDS 71-1759). The chemical reaction for the formation of monetite can be simplified as

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Monette Trombone Mouthpieces

Monette trombone mouthpieces, like Monette trumpet and tuba mouthpieces, feature the acoustic innovation called constant pitch center. This means they require less adjustment in body and slide positions when changing registers or dynamic ranges. In addition to the pitch center improvements Monette mouthpieces provide, the standard Monette trombone mouthpieces also have significantly more mass than most conventional mouthpieces. This means more stability of response and improved sound placement and projection. A light body (LT) model, with about the same mass as conventional designs, is also available for all tenor trombone mouthpiece models. By popular demand, all Monette low brass mouthpieces incorporate Prana� technology, at a special low price.

How to Select a Monette Mouthpiece
Because of the inconsistent playing qualities found in conventional mouthpiece designs, players have become accustomed to accepting compromises in mouthpiece size in order to maintain a given range and endurance in their playing. Monette mouthpieces are designed to eliminate these frustrating compromises and to promote an easier and more consistent approach to equipment selection.

Monette constant pitch center mouthpiece designs negate the old rules of choosing equipment, including how to pick the best size mouthpiece for a given musical task. One of Monette's primary goals in working with clients is to help them let go of old ideas about how they listen to themselves as they play, how they choose instruments, and how they choose mouthpiece sizes.

If brass players only had to play in the middle register and for no more than an octave in range, most players would be using a larger mouthpiece than they currently use. When choosing your first Monette mouthpiece, we generally suggest trying a size that is at least a little bit larger than you may be accustomed to. A slightly larger size in Monette equipment will actually enhance one�s upper register and fill out one�s sound because it encourages the player to play down into the center of the equipment in a way that is not possible on conventional equipment.

Not only do players find that using larger sizes is advantageous when using Monette mouthpieces, but they also find they can more easily change mouthpiece sizes for different styles of playing without suffering the usual acclimation problems.

All Monette mouthpieces come with larger throat sizes than most players of conventional mouthpieces have been accustomed to. The throat sizes for each model are optimized for each individual mouthpiece design. When larger throats are used in conventional mouthpieces, the upper register goes even flatter than it already does with traditional, mass-produced designs; with Monette constant-pitch-center designs, this is no longer an issue.

When playing Monette low-brass mouthpieces, it is essential to play without the physical adjustments we have learned to make for the inconsistent pitch center of conventional equipment. For more information, please refer to Monette's essay on Pitch Center, Body Use, and Resonance. and the Acclimation Guide .

Click here to read Norlan Bewley's excellent review of Monette mouthpieces.

Synthesis of Mercaptoethylammonium Chloride in Alkaline Medium

Synthesis of Mercaptoethylammonium Chloride in Alkaline Medium

A new way synthesis of mercaptoethylammonium chloride is reported. Using NaOH replace HCl, the results present that the target product can be made in alkaline medium and the velocity of new way is much faster than the tradition one, which is hydrolyzed at high pressure. ¹H NMR and IR characterized the structure of the product.

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  • Hydrothermal synthesis of monetite and hydroxyapatite from monocalcium phosphate monohydrate

    Hydrothermal synthesis of monetite and hydroxyapatite from monocalcium phosphate monohydrate Abstract

    Monetite and hydroxyapatite have been synthesized by hydrothermal treatment of monocalcium phosphate monohydrate (MCPM) suspension at 160°C and 200°C. The monetite formed whiskers typically having length, diameter and aspect ratio in the range of 26–40 μm, 1–2 μm and 20–26, respectively and the hydroxyapatite shaped needle like crystals typically being in the range of 0.2–0.5 μm in length and 0.02–0.04 μm in diameter. The morphology of the crystals seems to be controlled mainly by the solubility of the reactant species. The phase of the hydrothermal product is determined by the combination of the pH and the Ca/P ratio of the aqueous solution. The whiskers obtained can be used as a bioactive reinforcement for composites.

    Keywords
    • Monetite ;
    • Whisker ;
    • Hydroxyapatite ;
    • Hydrothermal ;
    • Synthesis ;
    • Calcium phosphate

    Corresponding author. Tel. +81-45-924-5323; fax: +81-45-924-5358 1

    Present address: Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok, 10330 Thailand.

    Present address: Department of Ceramic and Materials Engineering, Rutgers, The State University of New Jersey, 607 Taylor Road, Piscataway, NJ 08854, USA.

    Copyright © 2001 Elsevier Science Ltd. All rights reserved.

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    Monette Bb Trumpet Mouthpieces

    Monette B1-1D Trumpet Mouthpiece
    A deepened version of the B1-1. Used by Kenneth Fung, principal trumpet of the Hong Kong Sinfonietta.
    compares to a Bach 1A, the very round -1 rim with no inside bite causing it to feel much wider

    Monette B1-1 S1 Trumpet Mouthpiece

    This mouthpiece provides tremendous depth of sound and stability of response. It has a unique round rim with an unusually deep cup. This is the largest mouthpiece Monette makes for Bb trumpet, and is only recommended for the most advanced players. Designed for Charles Schlueter, principal trumpet of the Boston Symphony Orchestra. Also used by Brazilian trumpet artist Nailson Simões.
    compares to a Bach 1A, the very round -1 rim with no inside bite causing it to feel much wider

    The S1 is for the S-Series (SLAP!) cup. It provides a huge volume and depth of sound with an immediate, fast response. This mouthpiece was designed for Ed Cord, Professor of Trumpet at Indiana University.
    compares to a Bach 1A, the very round -1 rim with no inside bite causing it to feel much wider

    Monette B1-1 S5 Trumpet Mouthpiece
    This model is very successful design. It has the same approximate cup depth as a B1-5 and B1-2 mouthpieces, with a uniquely shaped "SLAP" cup. Very popular with Symphony players who are looking for a more efficient version of a B1-1.
    compares to a Bach 1B, the very round -1 rim with no inside bite causing it to feel much wider

    Monette B1-2D Trumpet Mouthpiece
    A deepened version of the B1-2. Used by many players who usually play a B1-2, when they need an even bigger, darker sound.
    compares to a Bach 1A, the flat -2 rim causing it to feel slightly narrower

    Monette B1-5 S4 Trumpet Mouthpiece

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    compares to a Bach 1C

    Monette B1-5LD Trumpet Mouthpiece
    With the approximate depth of the B4LD, this model is often used by classical musicians who play a B1-5 or B1-5M size mouthpiece and who want a "Pops" mouthpiece they can play for an entire show - even in the low register - and still have considerable help in the lead trumpet range. This model has been updated so that the rim now exactly matches the other B1-5 series mouthpieces.
    compares to a Bach 1D; the 1-5 is Monette's copy of a Bach 1C rim

    Monette B2� S3 Trumpet Mouthpiece

    Many players like the rim feel of a B2, but want something just a little smaller. Or even more commonly, they play a B3 and they want something just a little larger---but they find the B2 is too large. This mouthpiece really feels like its own size---and it does produce a larger sound than the B3 without losing the intimacy many classical chamber musicians need.
    compares to a Bach 1½C

    Monette B3F S7 Trumpet Mouthpiece
    For years musicians have asked us for a mouthpiece between a B2 and a B3 in size with a comfortable rim, a huge sound, and an extra-quick response. Here it is: the new B3F S7 mouthpiece, designed for Seattle recording artist, Adam Rapa. This mouthpiece is Adam's main mouthpiece for all-around playing. The rim is slightly flatter and has a bit more of a cushion contour than the B3 or B2, with an inside diameter falling between the two sizes. The cup shape is an extreme SLAP with a relative depth of 5.5 on our scale; this is between the depth of our B6 and B2 models, slightly closer to the B6. The extreme SLAP cup shape provides a very large cup volume for its depth, which helps the player produce a remarkably full sound for a mouthpiece of this size. The shape of the cup also provides help in the upper register.

    Monette B3 S3 Trumpet Mouthpiece
    Similar to but slightly narrower and more shallow than the B2, this mouthpiece is especially popular for classical chamber work. Used by Joakim Agnas, principal trumpet of the Stockholm Royal Opera and a founding member of the Stockholm Chamber Brass.
    compares to a Bach 1�C

    Monette B3F FL Trumpet Mouthpiece
    This is the Adam Rapa B3F S7 mouthpiece, made in a trumpet configuration but with a FLUMPET cup. We make these special, deep V-shaped cup mouthpieces with various rim sizes for both classical and jazz players all the time. They provide a great way to completely change your sound and are sometimes used when a player does not want to carry two horns to a performance. These FLUMPET cup mouthpieces are also great for warming down after a long set. They have lots of room and accommodate swollen chops when necessary, and can provide a great way to give your chops a break on a long gig. Perfect for ballads.

    Monette B4 S3 Trumpet Mouthpiece
    The SLAP cup version of the B4. The SLAP mouthpieces hold intensity better at soft dynamics, and offer a wider variety of articulation. When you play aggressively on them, the impact at the start of each note can sound and even feel like a "slap!" The top part of the cup is slightly more bowl shaped, which helps produce a larger sound. The "turn" of the "S" in the cup profile (where the mouthpiece cup turns from concave to convex) is more pronounced, making the mouthpiece more efficient for a faster response. The bottom of the cup has a more generous blend into the throat, which produces larger "targets" on every note so the mouthpiece is more forgiving to play.

    Monette B4S S2 Trumpet Mouthpiece
    The SLAP cup version of the B4S. The SLAP mouthpieces hold intensity better at soft dynamics, and offer a wider variety of articulation. When you play aggressively on them, the impact at the start of each note can sound and even feel like a "slap!" Very similar to the B4 but with less bite to the rim and a slightly brighter sound. This mouthpiece is as deep as the B4, but has a more efficient shape to the cup, making it especially good for upper register work. This rim and cup design is used by New York jazz and recording artist Lew Soloff.
    compares to an old Bach 3C

    Monette B6 S1 Trumpet Mouthpiece
    Atlanta lead trumpet player, Ron Turner, asked Dave Monette several years ago if there were any way to improve on the B6 mouthpiece he had played for years. After spending some time on the computer and making prototypes, we came up with the B6 S1 mouthpiece. It has exactly the same rim as the B6, and has a SLAP cup that helps the player produce a better sound, while providing an even faster response.
    compares to a Bach 3C

    Monette B7F Trumpet Mouthpiece
    This model has a medium-sized, slightly funnel-shaped cup that is very efficient. The rim is slightly flat, with a medium bite. This versatile mouthpiece is appropriate for players who prefer a smaller mouthpiece. It can be used in both small group jazz and some lead trumpet applications. Designed for jazz legend Art Farmer.
    compares to a Bach 7C

    Monette B8 Trumpet Mouthpiece
    This model is the smallest mouthpiece Monette makes that still has a substantial cup depth. The cup is a fairly deep bowl shape, and helps the player produce a lovely sound in spite of the quite narrow inner rim diameter. This model was designed for Tony Neenan of Cork, Ireland.
    compares to a Bach 10�C

    Synthesis Of An Orthopedic Cement By The Addition Of Anhydrous Calcium Hydrogen Phosphate To Calcium Sulfate Hemihydrate - Free Essays

    Synthesis Of An Orthopedic Cement By The Addition Of Anhydrous Calcium Hydrogen Phosphate To Calcium Sulfate Hemihydrate

    This Free Essays Synthesis Of An Orthopedic Cement By The Addition Of Anhydrous Calcium Hydrogen Phosphate To Calcium Sulfate Hemihydrate and other 60,000+ term papers, college essay examples and free essays are available now on ReviewEssays.com

    Autor: reviewessays • November 23, 2010 • 2,234 Words (9 Pages) • 1,096 Views

    Commercially available calcium sulfate hemihydrate (CSH) powders were mixed with anhydrous calcium hydrogen phosphate (monetite) in order to develop a novel resorbable orthopedic cement. The setting solution, distilled water, converted the CSH into gypsum as proven by an X-ray diffraction. This conversion into gypsum is what gives the cement its high compressive strength. The addition of monetite gives the cement a high bioresorbablity and remodeling ability that is not present in the pure CSH cements on the market today. Instead of merely dissolving into powder when placed in body fluids like CSH cements, the phosphate-enhanced cement in vivo may convert into apatitic bone-like structures.

    Thanks to the considerable advances in orthopedic surgery in the past twenty years, surgeons today are faced with many different techniques and substances with which to fill and correct bone defects. The most common treatment of choice for these corrections, however, despite new technologies, is autologous bone grafting. This is a process in which the surgeon scrapes bone cells from the patient's hipbone to place in the defect site. This treatment displays three main characteristics associated with the bone healing process: osteoconduction (the ability of materials to serve as a scaffold for new bone growth), osteoinduction (the ability of materials to promote and/or stimulate the formation of new bone), and osteogeneration (the ability to directly create bone tissue) (Smith & Smith, 2000). However, there are also disadvantages to the bone grafting method. Pain, infection, or nerve damage is reported by 10-25% of all patients and there may not be a sufficient amount of material available at the harvesting site, as often is the case in children. For the surgeon, disadvantages include a much longer operation time (Bloemers, Blokhuis, Patka, Bakker, Wippermann, & Haarman, 2003). Using an artificial bone substitute in place of autologous bone grafting has helped to circumvent these difficulties and various artificial bone substitutes have been developed for this purpose.

    Calcium sulfate hemihydrate (CSH) is used as an artificial bone substitute and is the most prevalent orthopedic cement in the United States market today, since its FDA approval in 2001. With the addition of a setting solution of water or saline, the CSH converts into a calcium sulfate dihydrate, more commonly known as gypsum. Gypsum shows good compressive strength results, however it does not maintain that strength for long after it is placed in body fluid. Gypsum in vivo does not withstand the effects of body fluid and dissolves into powder within the first few months after the surgery, before strong new bone can replace it. The optimal cement would uphold the mechanical strength during the stages of cellular resorption in the first three to four months but would be gradually replaced by new bone at the defect site within a year of the operation (Tas, 2004).

    When synthesizing a novel orthopedic substitute, one must consider many various factors including toxicity, pH, and body temperature. The elements and components of a cement can not contain materials that could harm the body. The material should ideally contain certain components similar to those of natural bone -- mainly calcium and phosphorous, and secondarily carbon, hydrogen, and oxygen. The calcium to phosphorous ratio in adult bones is normally around the number 1.67. Likewise, the material cannot alter the pH of the blood (pH=7.4). Having a substitute that is more alkaline or more acidic than 7.4 would alter the pH of the blood and result in catastrophic and often fatal consequences. Therefore, calcium hydroxide (Ca(OH)2), although containing elements of natural bone, would not be a useful chemical in a bone cement because it is such a strong base. The material must also be able to remain solid at the normal human body temperature of 37 ˚C (Joschek, Nies, Krotz, & Gopferich, 2000).

    An addition of calcium-phosphate to CSH may synthesize a cement with a strength comparable to that of pure CSH, but with a more ideal bioresorbability rate. The addition of phosphate into the CSH mixture may also produce more apatitic growth because the cement would better imitate the composition of natural bone, and thus more natural bone would create more strength. The cement would also be much more slowly absorbed into the body as it is replaced by natural bone, ideally within six months to a year after the operation. It is hypothesized that by adding CaHPO4 in proper ratios to CSH, a more ideal bioresorbability and bioactivity rate with a comparable compressive strength will be achieved.

    Methods and Materials

    Anhydrous calcium hydrogen phosphate (CaHPO4) was measured out in ratios of 5%, 10%, and 33% compared to Calcium sulfate hemihydrate (CSH). The powders were then mixed together using a mortar and pestle in wet form in order to ensure that the powders are completely mixed together. To do this "wet" mixture, enough ethanol must be used to have a liquid-to-powder ratio equal to 0.50. The ethanol and powders were mixed until a liquid paste was formed. The ethanol mixture was then placed in a 60 Ñ"C oven for 90 minutes to allow for the ethanol to completely evaporate. The setting solution of distilled water was added into the powder mixture using the liquid-to-powder mass ratio of 0.40 after the ethanol had fully evaporated. The water and CaHPO4-doped CSH powder was then mixed thoroughly for 3 minutes until a workable paste was formed. The paste was then put in a steel die to be pressed at 2,000 psi for approximately 8 minutes. Within this time, a perfect cylindrical pellet formed. The pellet must be removed from the steel die, and then placed in a 37 Ñ"C oven to dry overnight.

    Several tests were performed on the samples in order to determine the effectiveness of the product. To determine its compressive strength, a perfectly cylindrical pellet is placed between two steel plates (2 centimeters thick) and loaded into the Instron Compression Machine. This machine would then slowly increases the pressure on the cylinders by pressing down on them eventually reaching a force of almost 13,800 N. The strength of the material was calculated by comparing the displacement relevant to the force applied. X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) tests were performed on the control samples as well as each of the doped samples to gain a better understanding of the composition and crystal structures of the samples. To perform XRD and FTIR tests, the pellet was crushed into a fine powder using a mortar and pestle. To determine how a sample would react within the setting