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1

Siyab Khan, Muhammad, Muhammad Tufail et Mateeullah Mateeullah. « Effects of Waste Glass Powder on the Geotechnical Properties of Loose Subsoils ». Civil Engineering Journal 4, no 9 (30 septembre 2018) : 2044. http://dx.doi.org/10.28991/cej-03091137.

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Foundation soils are most affected by different problems when it comes to the loose soil having low shear strength and bearing capacity. Failure of the soil with settlement and shear arises when the shear stresses in the soil exceed the limit. This study is keen to observe the effects of utilization of waste broken glass in the enhancement of Geotechnical properties of soil by performing different laboratory tests. Collection of the soil sample from was concluded from Pabbi, Peshawar, KPK, and Pakistan, which is a low strength soil, are also being called soft soil having low bearing capacity. Furthermore, this particular soil was needed to be enhanced. The physical, chemical and engineering properties of virgin soil were contemplated and the soil was treated with added substances of Glass Powder to stabilize the local soil. Addition of Glass Powder was finished in different proportions that are 4%, 8% and 12% etc. Performance of different tests as Gradation, Specific Gravity, Standard Proctor compaction, Atterberg Limits, Direct Shear, CBR and so forth were done. The results were concluded, based on the Glass Dust stabilization analysis. It was obtained that pulverized glass can be effectively used as a soil stabilizer as mainly the strength characteristics were observed to be valeted. The Results showed that the gradation of soil is narrow from the particle size analysis. Plasticity index (P.I), Liquid limit (L.L) and plastic limit (P.L) were decreased with the addition of Glass powder. The reason behind decreasing P.I is maybe the fact that the Glass powder is cohesionless. Ideal percentage of Glass Powder as a stabilizer is 8%. Such improvements included an achievement of the highest CBR obtained at the 4%, 8% and 12% of powdered glass content. The reason is that the glass is pozzolanic material when blended with soil gives additional strength. The achievement of the increasing rate of the values of angle of internal friction on 4% and 8% and decreasing rate of values obtained at 12% powdered glass substances. Cohesion rate decreases up to 8% and starts increasing at 12%. Maximum dry density increasing as the density of glass is higher than such soil and Optimum moisture content (OMC) is decreasing because of low absorption capacity of glass. The study showed that the best stabilizer for the case study (Pabbi, Peshawar) is the Glass Powder and the optimum dose is 8 %.
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Petersen, Alexander S., Andrew M. Cheung, Henry J. Neilson, S. Joseph Poon, Gary J. Shiflet et John J. Lewandowski. « Processing and Properties of Ni-Based Bulk Metallic Glass via Spark Plasma Sintering of Pulverized Amorphous Ribbons ». MRS Advances 2, no 61 (2017) : 3815–20. http://dx.doi.org/10.1557/adv.2017.605.

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ABSTRACTNi-based bulk metallic glasses and composites with high absolute densities exceeding 11 g/cm3 were synthesized via spark plasma sintering of Ni45Co10Ta25Nb20 powders produced from pulverized, melt-spun amorphous ribbons. Optimizing the synthesis via selection of sintering temperature, uniaxial load pressure, and powder mechanical screening yielded samples with relative densities of nearly 100% and hardness values in excess of 12.5 GPa without cracking. Mechanical testing included Weibull modulus determination for hardness and compression testing at 10-3 s-1 and 103 s-1 strain rates. The capability of using spark plasma sintering to fabricate high hardness, high density, large scale metallic glasses is demonstrated. The mechanical properties of these compacted comminuted melt-spun glass ribbons are presented.
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He, Pingping, Chi Sun Poon et Daniel C. W. Tsang. « Comparison of glass powder and pulverized fuel ash for improving the water resistance of magnesium oxychloride cement ». Cement and Concrete Composites 86 (février 2018) : 98–109. http://dx.doi.org/10.1016/j.cemconcomp.2017.11.010.

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Watari, Takanori, Katsuhiro Ogawa, Toshio Torikai, Mitsunori Yada, Masaki Akiyama et Masaki Ida. « Fabrication of Porous Plate with Bimodal Pore Size Distribution Using Molten Slag from Incinerator ». Materials Science Forum 569 (janvier 2008) : 289–92. http://dx.doi.org/10.4028/www.scientific.net/msf.569.289.

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Porous plate with bimodal size distribution was prepared using the molten slag from the incinerator. The slag was pulverized to 1-10μm using a planetary ball mill. On heating the pellet formed with this powder, its relative density at 750°C and 800°C were 70% and 85%, respectively. At 750°C, each particle partially attached together at the contacted point. At 800°C, however, all particles melted, coagulated together and increased their size. The slag powder was granulated using a tumbling granulator, resulting granules of 0.5-5mm size. The compressive strength of the granule sintered at 750°C was 0.39 kgf. The density of the granule decreased by ~60%. The sintered granules were mixed with a proper amount of glass powder and starch water, and the slurry was cast to a mold (φ80mmx10mm). After drying the cast plate, it was heated at 630°C. The density of the plate was 1.2 gcm-3, ~43% of original slag value. The sound absorption coefficients of the plate were 0.02 and 0.4 at 200Hz and 1500Hz, respectively.
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He, Bifan, et Guangjin Wang. « Is ceramsite the last straw for sewage sludge disposal : a review of sewage sludge disposal by producing ceramsite in China ». Water Science and Technology 80, no 1 (1 juillet 2019) : 1–10. http://dx.doi.org/10.2166/wst.2019.223.

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Abstract With the rapid development of urbanization, the amount of urban sewage treatment is increasing. Waste activated sludge (WAS) is a by-product of sewage treatment, and its output is increasing year by year. How to properly handle WAS is related to the sustainable development of the sewage treatment industry. The production of ceramsite from WAS is an effective way to realize the utilization of sludge. This paper comprehensively describes the use of WAS as raw material, adding clay, cement, glass powder, shale, coal gangue, river sediment, pulverized fly ash and other auxiliary materials (AM) to produce sintered sewage sludge ceramsite and non-sintered sludge ceramsite. This paper analyzes the advantages and disadvantages of the process of making ceramsite from WAS. The research points out the development prospect of ceramsite from WAS.
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Adetayo, Oluwaseun, Okwunna Umego, Olugbenga Amu, Feyidamilola Faluyi, Adefunke Odetoye et Anthony Bucknor. « Performance Evaluation of Ternary Blends of Pulverized Cow Bone Ash and Waste Glass Powder on the Strength Properties of Concrete ». Trends in Sciences 19, no 8 (15 mars 2022) : 3222. http://dx.doi.org/10.48048/tis.2022.3222.

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The amounts of agricultural waste in cow bone and industrial waste glass in Nigeria have been expanding significantly, thereby increasing the danger to general wellbeing particularly in urban communities. This research examined the suitability of ternary blends of pulverized cow bone ash and waste glass powder (PCBAWGP) equally combined and partially replaced Portland cement in 0, 10, 20, 30 and 40 % percentages in concrete production. Physical and chemical properties were done on the concrete constituent materials. Compressive and tensile strengths of the hardened concrete of grade M20, mix proportion 1:2.17:3.4 were tested after 7, 14, 28, 60 and 90 days. The result of the physical properties uncovered that PCBAWGP had 2.70, 2.05 % and 1364 kg/m3 for specific gravity, moisture content and bulk density, respectively. From the consequences of the compressive strength, it showed that as the curing age of the concrete increases, the compressive strength expanded, the compressive strength outcomes at 10 % PCBAWGP partially replaced concrete is 15.55, 24.15, 19.85, 27.60 and 37.98 N/mm2 individually at 7, 14, 28, 60 and 90 days. At 90 days curing age, the tensile strength results for the control mix and 20 % PCBAWGP replacement was 2.72 and 1.88 N/mm2, respectively. The concrete strengths improved with concrete age and this was statistically affirmed utilizing ANOVA. This investigation showed that utilizing PCBAWGP in concrete is sustainable thereby reducing the dumped wastes and lessen CO2 outflows into the atmosphere by diminishing the extent of Portland cement in unit volume of cement produced. HIGHLIGHTS The compressive strength of concrete reduces as % pulverized cow bone ash and waste glass powder PCBAWGP increases. The compressive strength generally increases with increase in age of curing. The minimum and maximum compressive strength of concrete at 10 and 40 % PCBAWGP content for 1:2.17:3.4 concrete mix ratio at 28- and 90-days curing age are 19.85, 37.98 N/mm2 and 15.68, 22.31 N/mm2, respectively The minimum and maximum tensile strength of concrete at 10 and 40 % PCBAWGP at 28- and 90-days curing age are 1.71, 2.19 N/mm2 and 0.70, 1.55 N/mm, respectively The result of the water absorption tests at 28 days and 90 days showed that concrete samples containing PCBAWGP built up a superior protection from harm by freezing as their outcomes were less than 7 % recommendation Concrete containing PCBAWGP contents up to 20 % as partial replacement for cement, fulfills the strength required for normal concrete From the production comparative cost analysis, concrete with PCBAWGP content, as partial substitution for cement, is cheaper than conventional concrete of equivalent strength GRAPHICAL ABSTRACT
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Alcantara Marte, Yanilka, Gaspar Ros Berruezo, Yulisa Alcantara Marte et Andrea Escotto Tejada. « Effect of different concentrations of pulverized mesocarp of Citrus paradisi Macf on the morphology and glass transition temperature of spray-dried lemon juice powder ». Food Science & ; Nutrition 6, no 6 (22 juin 2018) : 1473–78. http://dx.doi.org/10.1002/fsn3.678.

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Grier, David G. « From Dynamics to Devices : Directed Self-Assembly of Colloidal Materials ». MRS Bulletin 23, no 10 (octobre 1998) : 21–23. http://dx.doi.org/10.1557/s0883769400029559.

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Colloidal suspensions have been part of the repertoire of human industry since Paleolithic artists first dispersed pulverized minerals in rendered animal fat to make paint. Remarkably, colloidal suspensions' primary industrial applications have changed little in the 20 or 30 millennia since. People use colloidal suspensions to disperse materials into fluid media without dissolving them. Familiar examples include surface coatings such as paints and inks, and slurries used for paper making and powder transport. Dividing the material finely enough to disperse it sometimes instills the resulting particles with novel properties. Ancient Romans took advantage of quantum confinement effects in metallic and semiconductor nanoclusters to color glass—research on the mechanisms and applications of nanoclusters' properties is ongoing. In all of these cases, the dispersed material is the important agent; colloidal dispersal simply facilitates its exploitation. More recently, colloidal particles have been deliberately used to modify the rheological properties of their carrier fluids. For these applications, the material from which the colloidal particles are made is less important than how their dispersal influences the medium.This issue of MRS Bulletin focuses on a new class of applications for colloidal suspensions stemming from some particles' innate ability to organize themselves into beautifully ordered arrays. These colloidal crystals acquire interesting and useful properties not only from their constituent materials but also from the spontaneous emergence of mesoscopic order that characterizes their internal structure.
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Hower, James, Dali Qian, Nicolas Briot, Eduardo Santillan-Jimenez, Madison Hood, Ross Taggart et Heileen Hsu-Kim. « Nano-Scale Rare Earth Distribution in Fly Ash Derived from the Combustion of the Fire Clay Coal, Kentucky ». Minerals 9, no 4 (30 mars 2019) : 206. http://dx.doi.org/10.3390/min9040206.

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Fly ash from the combustion of eastern Kentucky Fire Clay coal in a southeastern United States pulverized-coal power plant was studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). TEM combined with elemental analysis via energy dispersive X-ray spectroscopy (EDS) showed that rare earth elements (REE; specifically, La, Ce, Nd, Pr, and Sm) were distributed within glassy particles. In certain cases, the REE were accompanied by phosphorous, suggesting a monazite or similar mineral form. However, the electron diffraction patterns of apparent phosphate minerals were not definitive, and P-lean regions of the glass consisted of amorphous phases. Therefore, the distribution of the REE in the fly ash seemed to be in the form of TEM-visible nano-scale crystalline minerals, with additional distributions corresponding to overlapping ultra-fine minerals and even true atomic dispersion within the fly ash glass.
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Kamitakahara, Masanobu, Chikara Ohtsuki, Yuko Kozaka, Masao Tanihara et Toshiki Miyazaki. « Apatite-Forming Ability of Glass-Ceramics Containing Whitlockite and Diopside in a Simulated Body Fluid ». Key Engineering Materials 309-311 (mai 2006) : 341–44. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.341.

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Tricalcium phosphate (3CaO⋅P2O5, TCP) is known as a biodegradable material and already used clinically as important bone-repairing materials. However, the control of its bone-bonding ability, i.e. bioactivity, and biodegradability is not easy. On the other hand, diopside (CaO⋅MgO⋅2SiO2) ceramic shows a potential of direct contact with bone and high mechanical strength, but low biodegradability. We expected that a glass-ceramic containing TCP and diopside show high bioactivity and high mechanical strength, as well as biodegradability. Glasses with composition x(3CaO⋅P2O5)⋅(100-x) (CaO⋅MgO⋅2SiO2) (x = 0, 38, 50, 60 mass%) were prepared. They were pulverized and the compacts of the resultant powders were heated to obtain the glass-ceramics. Only diopside was precipitated at x = 0 in the glass composition, whitlockite (β-TCP) and diopside were at x = 38, 50 and 60, when the compacts were sintered at 1200 °C. The prepared glass-ceramics formed apatite on their surfaces in a simulated body fluid (SBF). This indicates that these glass-ceramics have a potential to show bioactivity.
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Szumiata, Tadeusz, Małgorzata Gzik-Szumiata, Katarzyna Brzózka, Bogumił Górka, Michał Gawroński, Ryszard Świetlik et Marzena Trojanowska. « Iron-containing phases in fly ashes from different combustion systems ». Nukleonika 60, no 1 (1 mars 2015) : 151–54. http://dx.doi.org/10.1515/nuka-2015-0030.

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Abstract The investigations of iron-containing phases existing in fly ashes were performed using transmission Mössbauer spectrometry. The examined samples of fly ashes were collected from different coal combustion systems, that is, stoker-fired boiler in municipal heating plant and pulverized coal boiler in power plant. Several phases are identified in the samples: iron oxides, paramagnetic aluminosilicate glass with Fe3+ ions and Al2O4-type spinel with Fe2+ ions. It was pointed out that proportions of contents of phases strongly depend not only on the combustion temperature but also on the way of ash collection.
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Jayashree, G., N. Gokulnath et S. Elaiyarasu. « Experimental Analysis on Partial Replacement of Cement by Glass Powder and Using of Steel Fiber ». International Journal for Research in Applied Science and Engineering Technology 11, no 8 (31 août 2023) : 1339–46. http://dx.doi.org/10.22214/ijraset.2023.55354.

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Abstract: Concrete consists of fine aggregate, coarse aggregate, water, and optional admixtures, such as Portland cement or another hydraulic cement. Because of its massive resource consumption, the concrete industry poses a serious danger to the sector's long-term viability. The concrete industry is struggling in part because of concerns about the environment and the economy. Many studies are currently being conducted on the utilisation of waste materials like Pulverised Fly Ash (PFA) and Ground Granulated Blast Furnace Slag (GGBS) as supplemental cementitious materials. Similar to PFA and GGBS, waste glass powder can be used to partially substitute cement during the hydration reaction. To some extent, waste glass can substitute cement in concrete and contribute to strength development if it is ground to a very fine powder and demonstrates pozzolanic properties due to its high SiO2 content. This research examined the Compressive, Tensile, and Flexural strengths of concrete that had been aged for up to 60 days with concrete that had been partially replaced with Glass Powder at percentages ranging from 0% to 40%. The aggregate test findings suggest that Waste Glass Powder could be used as a suitable cement replacement in construction projects. Fibre reinforced concrete (FRC) is a composite building material made from small, discontinuous fibres that are randomly distributed throughout the concrete part. Steel, glass, and polymer fibres, as well as fibres originating from natural sources, are the most common types of fibre used in cement-based composites. The tendency of fibres to be more closely spaced than traditional reinforcing steel bars makes them more effective at preventing cracking. It's important to note that fibre is not a suitable replacement for steel bars when reinforcing concrete.
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Takaaki, Wajima, et Masayuki Miyagawa. « Recycling of Waste Glass Fiber Reinforced Plastics (GFRP) via Pyrolysis with Sodium Hydroxide using Microwave Heating ». Key Engineering Materials 920 (16 mai 2022) : 68–73. http://dx.doi.org/10.4028/p-t275a5.

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Glass fiber reinforced plastics (GFRP) are composite materials with high strength and flame retardancy, and the disposal process is expensive to cause illegal dumping. Therefore, new recycling technology of waste GFRP is desired. In this study, recycling of waste GFRP via pyrolysis with sodium hydroxide (NaOH) under an inert atmosphere using microwave heating was attempted by carbonization of resin and conversion of glass fiber into soluble sodium silicate. The pyrolysis behavior of GFRP, the characteristics of the obtained residue, and the silica extraction into the solution were compared for microwave heating and conventional heating. In both heatings, the carbonization of the resin and the conversion of the glass fiber into soluble sodium silicate were confirmed by pyrolysis with NaOH, and the sample after the pyrolysis treatment can be pulverized into a powdery residue by washing the solution without mechanical crushing. In comparison with conventional heating, microwave heating could reduce the time for heat treatment (41.3% reduction), to reduce the energy consumption (75% reduction), suggesting that microwave heating can provide more efficient treatment.
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Haider, Usman, Zdenek Bittnar, Lubomír Kopecky, Vít Šmilauer, Jaroslav Pokorny, Martina Zaleska, Zdenek Prošek et Vladimír Hrbek. « DETERMINING THE ROLE OF INDIVIDUAL FLY ASH PARTICLES IN INFLUENCING THE VARIATION IN THE OVERALL PHYSICAL, MORPHOLOGICAL, AND CHEMICAL PROPERTIES OF FLY ASH ». Acta Polytechnica 56, no 4 (31 août 2016) : 265–82. http://dx.doi.org/10.14311/ap.2016.56.0265.

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The properties of fly ashes vary because of the differences in the properties of their individual particles, and the determination of variation in these properties is of interest to the industries which use pulverized raw fly ash in applications, such as in cementitious materials and in the recovery of certain rare elements from raw fly ash. To investigate the differences in individual particles, four pulverized raw fly ashes from thermal power plants of the Czech Republic were used in this research. It was observed from FE-SEM that all four fly ashes consist of glassy hollow spherical, solid spherical, porous spherical, bright spherical, porous slaggy and compact slaggy particles. Box and whisker diagrams were plotted from the data of EDX individual particle analyses, which showed that the data of percentages for the Si, Al, and Fe elements is more scattered as compared to other elements. It was further observed from ternary phase diagrams and pseudo coloured images, that nature of fly ash particles changes from alumino silicate glassy to alumino silicate calcite metallic to pure ferro-metallic,where glassy particles showed high percentages and pure calcite particles were absent in fly ashes. Furthermore, a comparison between the XRF, the EDX total area analyses, showed that the EDX individual particle analysis gives more realistic and reliable data with median, mean, and the standard deviation for percentages of each element present in the fly ashes.
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Jeremiah, Jeremiah J., Samuel J. Abbey, Colin A. Booth et Anil Kashyap. « Geopolymers as Alternative Sustainable Binders for Stabilisation of Clays—A Review ». Geotechnics 1, no 2 (29 novembre 2021) : 439–59. http://dx.doi.org/10.3390/geotechnics1020021.

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The need to transit to greener options in soil stabilisation has revamped research on the use of industrial and agricultural by-products in order to cut down on the current carbon footprint from the use of ordinary Portland cement (OPC) and lime related binders for the treatment of problematic soils. This study is a review on the use of geopolymers constituted by alkali activation of several industrial wastes such as pulverised fuel ash (PFA), ground granulated blast furnace slag (GGBS), metakaolin (MK), glass powder (GP), palm oil fuel ash (POFA), silica fume (SF), rice husk ash (RHA), volcanic ash (VA), and marble powder (MP) for the stabilisation of weak clays. The performance of stabilised clays as subgrade and subbase materials for road pavement construction was evaluated by comparing the 7 day UCS of the treated clays with the strength requirement for stabilised materials as outlined in BS EN 16907-4. The result of the study shows that geopolymers can be employed in improving the engineering properties of problematic clays to meet practical applications. Strength improvement was observed in the stabilised clays with increased precursor content, molarity of alkaline activator, and curing period.
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Asanammal Saral, J., S. Gayathri, M. Tamilselvi et B. Raghul Raj. « An Experimental Study on Fibre Reinforced Geopolymer Concrete Composites- Glass Fibre, Copper Slag ». International Journal of Engineering & ; Technology 7, no 3.34 (1 septembre 2018) : 433. http://dx.doi.org/10.14419/ijet.v7i3.34.19344.

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The major problem of the world is facing today is environmental pollution. It is well known that for the production of 1-ton of cement consumes more energy and exhibit 0.8-ton of CO2 .On the other hand Fly ash is a residue from the combustion of pulverized coal from the flue gases of thermal power plant. Recently, the fly ash is not effectively used and a large part of it is disposed in landfill. Due to this problem the various researchers have sort for a new binder to minimize the consumption of OPC. This study evaluates the strength of geopolymer concrete having fly ash as the major binding material and the sand a fine aggregate was replaced with copper slag of 40% and glass fiber to enhance the mechanical properties have been presented. This paper analyses on the mechanical properties of eopolymer concrete composites such as compressive strength, split tensile strength and water absorption in heat curing at 60˚C for 24 hrs in hot air oven. Glass fibers were added in the mix in the volume fraction of 0.5%, 1.0%, 1.5% and 2.0% volume of the concrete. The influence of fiber content in terms of volume fraction on the compressive, split tensile strength of geopolymer concrete is presented. The result shows the elevated performance of the properties exhibited by the geopolymeric concrete with and without fibres.
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Tonetto, Mateus Rodrigues, Marcelo Ferrarezi de Andrade, Shelon Cristina Souza Pinto, Alvaro Henrique Borges, Matheus Coelho Bandéca, Luiz Rafael Calixto, Erico Damasceno Barros et Fabrício Viana Pereira Lima. « Degree of Conversion and Hardness of Two Different Systems of the VitrebondTM Glass Ionomer Cement Light Cured with Blue LED ». Journal of Contemporary Dental Practice 14, no 2 (2013) : 244–49. http://dx.doi.org/10.5005/jp-journals-10024-1307.

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ABSTRACT This study investigated the physicochemical properties of the new formulation of the glass ionomer cements through hardness test and degree of conversion by infrared spectroscopy (FTIR). Forty specimens (n = 40) were made in a metallic mold (4 mm diameter x 2 mm thickness) with two resin-modified glass ionomer cements, VitrebondTM and VitrebondTM Plus (3M/ ESPE). Each specimen was light cured with blue LED with power density of 500 mW/cm2 during 30 s. Immediately after light curing, 24h, 48h and 7 days the hardness and degree of conversion was determined. The Vickers hardness was performed by the MMT-3 microhardness tester using load of 50 gm force for 30 seconds. For degree of conversion, the specimens were pulverized, pressed with KBr and analyzed with FT-IR (Nexus 470). The statistical analysis of the data by ANOVA showed that the VitrebondTM and VitrebondTM Plus were no difference significant between the same storage times (p > 0.05). For degree of conversion, the VitrebondTM and VitrebondTM Plus were statistically different in all storage times after light curing. The VitrebondTM showed higher values than VitrebondTM Plus (p < 0.05). The performance of VitrebondTM had greater results for degree of conversion than VitrebondTM Plus. The correlation between hardness and degree of conversion was no evidence in this study. How to cite this article Calixto LR, Tonetto MR, Pinto SCS, Barros ED, Borges AH, Lima FVP, de Andrade MF, Bandéca MC. Degree of Conversion and Hardness of Two Different Systems of the VitrebondTM Glass Ionomer Cement Light Cured with Blue LED. J Contemp Dent Pract 2013;14(2): 244-249.
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Húlan, Tomáš, Igor Štubňa, Ján Ondruška et Anton Trník. « The Influence of Fly Ash on Mechanical Properties of Clay-Based Ceramics ». Minerals 10, no 10 (21 octobre 2020) : 930. http://dx.doi.org/10.3390/min10100930.

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Elastic properties of mixtures of illitic clay, thermal power plant fly ash (fluidized fly ash—FFA and pulverized fly ash—PFA), and grog were investigated during the heating and cooling stages of the firing. The grog part in the mixtures was replaced with 10, 20, 30, and 40 mass% of the fly ash, respectively. The temperature dependence of Young’s modulus was derived using the dynamical thermomechanical analysis, in which dimensions and mass determined from thermogravimeric and thermodilatometric results were used. Flexural strength was measured at the room temperature using the three-point bending test. The following results were obtained: (1) Bulk density showed a decreasing trend up to 900 °C and a steep increase above 900 °C. During cooling, the bulk density slightly increased down to the room temperature. (2) Young’s modulus increased significantly during heating up to ~300 °C. Dehydroxylation was almost not reflected in Young’s modulus. At temperatures higher than 800 °C, Young’s modulus began to increase due to sintering. (3) During cooling, down to the glass transformation, Young’s modulus slightly increased and then began to slightly decrease due to microcracking between phases with different thermal expansion coefficients. (4) Around the β→α quartz transition, radial stresses on the quartz grain altered from compressive to tensile, creating microcracks. Below 560 °C, the radial stress remained tensile, and consequently, the microcracking around the quartz grains and a decreasing Young’s modulus continued. (5) With a lower amount of PFA and FFA, a higher Young’s modulus was reached after sintering. The final values of Young’s modulus, measured after firing, show a decreasing trend and depend linearly on the part of fly ash. (6) The flexural strength measured after firing decreased linearly with the amount of the fly ash for both mixtures.
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Choji, Solomon, Faith Damla, Larry Barde, Riyang Zakka et Adeshola Adegbite. « ANTI-DIABETIC EFFECTS OF ETHANOL LEAF EXTRACT OF ONIONS (Allium cepa) ON ALLOXAN-INDUCED DIABETIC WISTAR ALBINO RATS ». BOKKOS JOURNAL OF APPLIED SCIENTIFIC REPORTS 1, no 2 (14 mars 2021) : 19–34. http://dx.doi.org/10.47452/bjasrep.v1i2.22.

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ANTI-DIABETIC EFFECTS OF ETHANOL LEAF EXTRACT OF ONIONS (Allium cepa) ON ALLOXAN-INDUCED DIABETIC WISTAR ALBINO RATS Choji Solomon S. Department of Biochemistry, Faculty of Natural and Applied Sciences, Plateau State University, Bokkos. P.M. B 2012, Jos. Nigeria. Chojisolomon@gmail.com +2347065752410 Damla Faith U. Department of Biochemistry, Faculty of Natural and Applied Sciences, Plateau State University, Bokkos. P.M. B 2012, Jos. Nigeria Barde Larry A. Department of Biochemistry, Faculty of Natural and Applied Sciences, Plateau State University, Bokkos. P.M. B 2012, Jos. Nigeria Zakka Riyang. Department of Food Science and Technology, Faculty of Agricultural Science, Federal University Wukari. P.M.B 1020 Adegbite Adeshola. Ladoke Akintola University of Technology. Ogbomoso. Oyo State. Abstract. Diabetes is a chronic disease characterised by high blood glucose level and abnormal metabolism of carbohydrates, protein and fat. The condition is characterised by persistent hyperglycaemia. Allium cepa leaf is a functional food used in traditional medicine for the treatment of diabetes mellitus. The use of plants especially vegetable as antidiabetic remedies have added interest of joining two basic diabetes mellitus control factors: food and medication. The ethanol extract of Allium cepa leaf was investigated for antidiabetic effects using alloxan- induced diabetic wistar albino rats. Wistar albino rats were randomly divided into six groups; Group A rats were non-diabetic control. Diabetes was induced in groups B, C, D, E and F by single intraperitoneal injection of alloxan (150mg/kg body weight). Group B were not treated and served as negative control group. Group C were treated with glibenclamide (5mg/kg body weight), thus served as postive control group. Groups D, E and F were treated with 200, 300 and 400 mg/kg body weight of the extract respectively for a period of two weeks through intraperitoneal route. The effect of treatment with the doses of the extract and standard drug were studied on blood glucose level, total serum cholesterol and body weight. Allium Cepa extract produced a dose- dependent significant reduction in the blood glucose level when compared with that of the control group. Significant total serum cholesterol reduction was observed at 300 and 400mg/kg. An observed decrease in body weight of the negative control group was recorded and significant increase for all other groups. The findings from this study indicate that the crude extract of Allium cepa leaf caused a significant hypoglycaemic and hypocholesterolemic activity in alloxan-induced diabetic rats thus, validates its use in ethno – medicine for the control of diabetes mellitus. KEY WORDS: Diabetes mellitus, Allium cepa, Alloxan, Blood glucose, Cholesterol Glibenclamide. 1.0 INTRODUCTION. Diabetes Mellitus (DM) is a group of metabolic disorders associated with disturbances in the metabolism of fuel molecules due to absolute deficiency of insulin, insufficient insulin secretion and / or its secretion [1]. It is a disorder that affects the body’s ability to make or use insulin. Insulin is a hormone produced in the pancreas that helps transport glucose (blood sugar) from the bloodstream into the cells so they can break it down and use it for fuel. People cannot live without insulin [2]. It is also a widespread endocrine disorder that is associated with considerable morbidity and mortality and is found in all population throughout the world [3] Despite the presence of anti-diabetic drugs in the pharmaceutical market, the treatment of diabetes with medicinal plants is often successful. Herbal medicine and plant components with insignificant toxicity and less or no side effect are notable therapeutic options for the treatment of this disease around the world [4]. The most common herbal active ingredients used in treating diabetes are flavonoids, tannins, phenols and alkaloids [5]. The existence of these compounds implies the importance of the anti-diabetic properties of these plants [4]. Allium cepa is one of the recognised medicinal plants known to possess several medicinal properties including lowering of blood pressure, antiseptic, hypoglycaemic and hypocholesterolemic activity [6]. In the rural communities, many people depend solely on medicinal plants for the treatment of diabetes due to its easy accessibility, affordability and availability even when the efficacy of the herbal remedies has not been established [6]. Dietary therapy is unarguably the best treatment for diabetes. The diabetic diet should be carefully monitored to minimize the load placed on the blood glucose regulating mechanism. The use of plants, especially vegetables, by the population as antidiabetic remedies has added interest of joining two basic diabetes mellitus control factors: food and medication [7]. This research is thus geared towards finding a medicinal plant that will not only increase the energy content of diabetics but also lower glycaemic index properties for the management of diabetic pressures in our society. 2.0 MATERIALS AND METHODS. 2.1 Materials. 2.1.1 Chemicals and Reagents. Baker Ltd Dagenham, England, BDH Chemicals Ltd; Poole England, Sigma Chemicals, St Louis, USA, Emzor Pharmaceuticals Industry Ltd, Nigeria and Randox Laboratories. London, UK. 2.1.2 Plant The Allium cepa leaves used for the experiment was bought from Barkin Ladi Market, Plateau State, Nigeria. The plants were identified by Professor Pob Poppva in the Department of Botany, University of Jos, Plateau State. A voucher specimen was deposited in the herbarium unit of the department. 2.1.3 Experimental Animals. A total of thirty-six (36) adult male Wistar albino rats weighing 80 to 150g and twelve (12) mice were used for the experiment. The experimental animals were purchased from Chris Animal Farm, G.R.A. Awka. They were housed six (6) rats per cage at the experimental Animal House of Biochemistry Department, Nnamdi Azikiwe University, Awka, Anambra State. They were acclimatized for two weeks under standard laboratory conditions and were maintained on water and Guinea growers mash pellet (Vital Feed Grand Cereals Nigeria Ltd, Jos, Nigeria) that was obtained from Eke Market, Awka, Anambra State. 2.2 Methods 2.2.1 Preparation of ethanol leaf extract of Allium cepa . The leaves of Allium cepa were properly washed with distilled water and dried at room temperature for three weeks. The dried leaves were then pulverised using corona manual grinding machine. The powdered samples of Allium cepa was weighed and exactly 1475g was extracted in 5 litres of 80% ethanol for 24 hours with occasional stirring, sieved and filtered using filter paper (Whatman number 1). The filtrate was then concentrated using a rotary evaporator at 600C and appeared as a dark brown gel solid. The extracts were kept in a labelled glass container and stored in a refrigerator until when required for reconstitution and administration. 2.2.2 Phytochemical Screening of Secondary metabolites(Constituents) The qualitative phytochemical screening of the ethanol leaf extract of Allium cepa was carried out using standard procedures as outlined by [8], [9]. 2.2.3 Acute toxicity and Median Lethal Dose (LD50) test of ethanol leaf extract of Allium cepa. The median Lethal Dose (LD50) was determined using Wistar albino mice as described by the modified method of [10]. Test animals were divided into six (6) groups. The first 3 groups which contain 3 animals each were given 10mg/kg, 100mg/kg and 1000mg/kg body weight of the ethanol extract of Allium Cepa leaves. The Allium Cepa extract was administered orally and was monitored for 24 hours. The last 3 groups which contain one animal each per group were then given 1600mg/kg, 2900mg/kg and 5000mg/kg body weight of the ethanol extract of Allium Cepa leaves and were observed for 24 hours. 2.2.4 Induction of Diabetes. Alloxan was prepared and induced by adopting the method of [11]. All rats, except for the normal control group were intraperitoneally injected with 150mg/kg body weight of the prepared alloxan dissolved in normal saline solution. The blood glucose levels of the rats were checked before the administration of alloxan using one touch glucometer (Fine touch, USA) and test strips. The rats were then fasted for 16 hours, but with free access to water after which they received an intraperitoneal injection of alloxan 150mg/kg body weight. The rats were orally given 20ml each of 10% glucose solution after 2 hours to prevent hypoglycaemia. The animals were allowed free access to food and water after alloxan administration. After 48 hours of the alloxan administration, blood was collected orbito-rectally and their glucose levels were checked using one touch glucometer and test strips. Diabetes was confirmed to have been induced if the glucose level was observed to be far much higher than normal (above 140mg/dl). 2.2.5 Experimental Design This study was carried out on alloxan –induced diabetic rats for two (2) weeks. A total of thirty-six (36) Wistar albino rats were used for the experiment. The albino rats were randomly divided into six (6) groups with six (6) rats in each group. The extract and the reference drug were administered intraperitoneally to the animals. Group A – Normal (non-diabetic control) Group B – Diabetic (negative) control group Group C – Diabetic (positive) control – this group received 5mg/kg body weight of glibenclamide. Group D – This group received 200mg/kg body weight of the extract. Group E – This group received 300mg/kg body weight of the extract. Group F – This group received 400mg/kg body weight of the extract The weights of the animals were carefully monitored before the induction and throughout the duration of the experiment. 2.2.6 Biochemical Assay 2.2.6.1 Blood glucose level determination Determination of the blood glucose level was done by the glucose-oxidase principle [12] using the one touch instrument and results were reported as mg/dl [13]. 2.2.6.2 Determination of total serum cholesterol. The cholesterol of the serum was oxidised to tetraene derivative by ferric ions derived from ferric perchlorate using four different test tubes that were marked test, control, standard and blank. The absorbance was measured (using spectrophotometer) at 590nm wavelength and compared with that of a pure solution of cholesterol [14]
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Abd El-Shakour, Zeinab A., Nahla I. Abd El Ghaffar, Gehan T. El-Bassyouni et Esmat M. A. Hamzawy. « Glass-Ceramics from Trachyte Rock- Limestone or Magnesite ». Silicon, 14 juillet 2022. http://dx.doi.org/10.1007/s12633-022-01990-3.

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AbstractInexpensive sintered glass-ceramic glaze was prepared from a mixture of Egyptian trachyte with either limestone or magnesite. A represented trachyte rock was pulverized to powder (<0.083 mm) and also both limestone and magnesite. The well mixed batches were melted near 1450 °C/3 h temperature then the glass melt was quenched in water, dried, pulverized to powder and finally shaped in moulds. The sintering process of the pre-shaped glasses, within 1000-1100 °C range, gave augite and olivine in case of trachyte-magnesite whereas wollastonite and Ca-olivine in case of trachyte-limestone. However, cristobalite was developed in both cases. The microstructures in both cases showed glassy matrix scattered with submicron and nano-size crystals either in irregular shape in case of trachyte-limestone or clear crystals in case of trachyte-magnesite. The densities of the sintered samples were in the range of 2.36 and 2.57 g/cm3 in case of the trachyte-limestone and 2.36 and 2.64 g/cm3 in case of the trachyte-magnesite. The coefficient of thermal expansion (CTE) and the hardness of the sintered glass-ceramic were in the range of 6.2-8.5 × 10−6 °C−1 and 440-563 GPa respectively. However, the CTE values decreased in case of trachyte-limestone whereas the hardness values were high in case of trachyte-magnesite. The present glass-ceramic samples had porcelain nature and could be used in cladding of wall and floor.
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Olofinnade, Oluwarotimi, Cynthia Chigere, David Nduka, Opeyemi Joshua et Babatunde Ogunbayo. « NOVEL MORTAR CONTAINING WASTE GLASS AND CLAY BRICK POWDER FOR SUSTAINABLE CONSTRUCTION ». Proceedings of International Structural Engineering and Construction 7, no 1 (août 2020). http://dx.doi.org/10.14455/isec.res.2020.7(1).sus-10.

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Due to the increasing need for sustainability, the need for a cleaner environment and resources conservation has now become very important. This study investigates the possible utilization of waste glass powder combined with pulverized fired clay brick wastes as a partial replacement for Portland cement in the production of mortar. The fired clay bricks and glasses were sourced as waste materials and then crushed into powder form. It is then combined and used to partially substitute Portland cement in the mortar at replacement levels of 0, 5, 10, 20, 25, 30, 40 and 50% using a mix ratio of 1:2.75 at 0.5 water-binder ratios. Physical, chemical and morphological characterization was carried out on the pulverized materials. Further, the compressive strength test was carried out on casted 100 mm cube samples after curing by immersion in water. Obtained results revealed the pozzolanic reactivity potential of the blended waste glass and fired clay brick powder due to their amorphousness and high silica content, while also exhibiting similar oxides compositions. Moreover, the obtained compressive strength results of the blended mortar depict improved strength especially at an optimum value of 15% cement substitute with the blended fired clay brick and glass powder compare to the control. It is therefore suggested that blended mix of waste glass and fired clay brick powder with cement can be used in mortar component instead of open disposal in a landfill.
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PATIL, DHANARAJ MOHAN, et KESHAV K. SANGLE. « EXPERIMENTAL INVESTIGATION OF WASTE GLASS POWDER AS PARTIAL REPLACEMENT OF CEMENT IN CONCRETE ». International Journal of Advanced Technology in Civil Engineering, janvier 2013, 59–64. http://dx.doi.org/10.47893/ijatce.2013.1062.

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Concrete is a construction material composed of cement, aggregates (fine and coarse aggregates) water and admixtures. Today many researches are ongoing into the use of Portland cement replacements, using many waste materials like pulverized fly ash (PFA) and ground granulated blast furnace slag (GGBS). Like PFA and GGBS a waste glass powder (GLP) is also used as a binder with partial replacement of cement which take some part of reaction at the time of hydration, also it is act as a filler material. In this study, waste glass powders have been used as replacements to the concrete ingredient i.e. cement and the mechanical properties like compressive strength are measured. Also we were studied the size effect of glass powder on strength of concrete. For checking strength effect of replacement of cement by glass powder, the cement is replaced at 10%, 20% and 30%. For study of size effect of glass powder the powder is divided in to two grades one is glass powder having size less than 90 micron and another is glass powder having particle size ranges from 90 micron to 150 micron. It is found from study, Initial strength gain is very less due to addition of GLP on 7th day but it increases on the 28th day. It is found that 20% addition of GLP gives higher strength. And also GLP size less than 90 micron is very effective in enhancement of strength
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Choi, Seung Hee, Seok Bin Kwon, Jung Hyeon Yoo, MinYoung Na, Bo Young Kim, HoShin Yoon, Seoung Hyok Park et al. « Fabrication of phosphor in glass using waste glass for automotive lighting application ». Scientific Reports 13, no 1 (17 mars 2023). http://dx.doi.org/10.1038/s41598-023-27685-2.

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AbstractWith advancement of technology, requirements for light-emitting devices are increasing. Various types of packaging technologies have been suggested to improve the performance of light-emitting diode (LED). Among them, phosphor in glass (PiG) is attracting attention due to its manufactural facility and easily tunable characteristics. As PiG draws increasing attention, research on glass materials is also being actively conducted. However, studies about glass in the field of phosphor are mainly conducted on fabrication. Only a few studies about recycling have been reported. Thus, the objective of this study was to recycle waste glass discarded in other fields due to breakage and failure and use it to fabricate phosphor in glass. Cylindrical waste glass was pulverized into powder with an average size of 12 μm, mixed with a phosphor and sintered to be reborn as a phosphor in glass to broaden the recycling route for waste glass.
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Eldera, Samah S., Sarah Aldawsari et Esmat M. A. Hamzawy. « Utilization of waste glass with natural pozzolan in the production of self-glazed glass-ceramic materials ». Nanotechnology Reviews 12, no 1 (1 janvier 2023). http://dx.doi.org/10.1515/ntrev-2022-0565.

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Abstract Significant self-glazed glass-ceramic was obtained from a natural pozzolan and external glass cullet. Natural pozzolan with/without glass cullet was fused to glass melt that quenched in water to glass frits. The dried glass frits were pulverized (<0.083 mm) and then shaped in a stainless mold. The thermal behavior of the glasses shows a widening of the crystallization temperature with the incorporation of the glass cullet between ∼800 and 950°C. Sintering of the shaped glass powder at 1,050°C/2 h lead to the crystallization of augite, enstatite, cristobalite, and hematite. The microcrystalline structure shows massive texture with pores in-between; however, at high magnification regular euhedral to subhedral crystals in submicron to nearly submicron size was developed in the glassy matrix and their microanalysis indicates the dominant augite. The density of the glass-ceramic samples decreases from 2,706 to 2,539 kg/m3 with the incorporation of glass wastes. The sample surfaces show, through force electron microscopy, the fineness and smoothness of the grains with the incorporation of the glassy portion. The microhardness values were between 6.43 and 6.11 GPa. The coefficient of thermal expansion increased from 32.87 (25–300°C) to 66.89 (25–500°C) × 10−7°C−1. The chemical resistance of samples in water (0.0002–0.0016) is better than in an acidic medium (0.0011–0.0017). These glass-ceramic enjoy good density, hardness, and thermal expansion and can be used in the ceramic industry and cladding walls and floors.
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Adetayo, Oluwaseun A., Okwunna M. Umego, Feyidamilola Faluyi, Adefunke O. Odetoye, Anthony O. Bucknor, Ayobami A. Busari et Ademola Sanni. « Evaluation of Pulverized Cow Bone Ash and Waste Glass Powder on the Geotechnical Properties of Tropical Laterite ». Silicon, 1 mars 2021. http://dx.doi.org/10.1007/s12633-021-00999-4.

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Girdhar, Sahil, et Parveen Raheja. « BONE CEMENT - BOON OR BANE (AN OVERVIEW) ». INTERNATIONAL JOURNAL OF SCIENTIFIC RESEARCH, 1 août 2023, 61–64. http://dx.doi.org/10.36106/ijsr/0405597.

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Polymethyl methacrylate (PMMA), is commonly known as bone cement, and is widely used for implant xation in various Orthopedic and trauma surgery. In reality, “cement” is a misnomer because, the word cement is used to describe a substance that bonds two things together. However, PMMA acts as a space-ller that creates a tight space which holds the implant against the bone and thus acts as a 1 'grout'. Bone cements have no intrinsic adhesive properties, but they rely instead on close mechanical interlock between the irregular bone surface and the prosthesis. Other types of commercially available bone cement like calcium phosphate cements (CPCs) and Glass polyalkenoate (ionomer) cements (GPCs) are successfully used in a variety of orthopedic and dental applications. CPCs are bio resorbable and biocompatible, but are mainly used in cranial and maxillo-facial 2 surgeries because of their low mechanical strength. HistoryThe pioneering work on PMMA technology is widely credited to German chemist Dr. Otto Rohm. In 1933, he patented Plexiglas, a PMMA product used in submarine periscopes and airplane canopies. This led to a sharp increase in demand and interest before and during the war. Kulzer (1936) found that a dough made by mixing his pulverized PMMA powder and liquid monomer hardened when he added benzoyl 4. peroxide and heated it to 100°C in a stone mold, making it malleable His rst clinical use of this PMMA mixture was in 1938, for the purpose of plugging a skull defect in a monkey. Surgeons used the heat-stable polymer Paladon 65 to close a human skull defect. This material was assembled into sheets in the laboratory and then molded 4 in the operating room . His modern day PMMA bone cement dates back to a patent by Degussa and Kulzer (1943). The patent described how MMA polymerizes at room temperature upon the addition of coinitiators (eg tertiary aromatic amines). Dentists were the rst to use this technology in dental xatives and dental instruments. British surgeon Dr. David Martin is widely credited for the rst use of bone cement in orthopedics. By John Charnley using "Dentacryl" for total hip arthroplasty in 19585. Initial clinical results were unsatisfactory due to mechanical and biological reasons for both the cement and the 4 loading platform . Dr. Charnley developed a new product called "bone cement" (Plexiglas) with more adaptive biological properties, which he actively marketed to the global orthopedic community. American orthopedic surgeon trained under Dr. Charnley learned 7 groundbreaking techniques at Wrightington Hospital . When these surgeons returned to the United States, they often brought back bags of bone cement, but this illegal trade began in the mid-1970s when the Food and Drug Administration approved the use of bone cement technology in the United States.Component PMMA is an acrylic polymer made by mixing two sterile ingredients (Table 1).A liquid 8 MMA monomer and a powdered MMA-styrene copolymer. When the two components are mixed, the liquid monomer polymerizes around the prepolymerized powder particles and hardens to form PMMA.An exothermic reaction produces heat.
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Mahmood, Aziz Hasan, Sumaiya Afroz, Alireza Kashani, Taehwan Kim et Stephen J. Foster. « The efficiency of recycled glass powder in mitigating the alkali-silica reaction induced by recycled glass aggregate in cementitious mortars ». Materials and Structures 55, no 6 (29 juin 2022). http://dx.doi.org/10.1617/s11527-022-01989-7.

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AbstractWith the potential for a decline in fly ash (FA) production over time, due to the phasing down of coal fired power plants, alternative supplementary cementitious materials need to be identified. The efficiency of pulverised glass powder (PGP) was studied for its reactivity and its capacity for inhibiting alkali-silica reaction (ASR) that results from utilisation of recycled glass as a fine aggregate (sand) replacement. Characterisations of pastes containing PGP reveal that PGP may possess latent hydraulic properties, resulting in a more than 75% strength activity index, together with better strength gain than FA-blended pastes. PGP also offered increased heat of hydration compared to FA, from a combination of the dilution effect, filler effect and early-age reactions of PGP. A comparable efficiency of PGP and FA in ASR expansion mitigation was confirmed with mortar bar expansions of less than 0.10% at cement replacement levels of at least 10%. Both PGP and FA provided alkali dilution and reduced the mass transport in hydrated cement paste from the refinement of larger pores to below 60 nm. The FA mix consumed calcium hydroxide and, thus, performed marginally better than the PGP mix in mitigating ASR. This pozzolanic reactivity is not evident for PGP, whereas in the literature glass powders are often regarded as pozzolanic. Microscopic images confirm that PGP and FA significantly limit the occurrence of ASR gels without altering its composition. It was concluded that PGP is a comparable ASR inhibitor to FA, despite the underlying differences in their mechanisms. The result of this research support the utilisation of recycled glass both as an aggregate, and as an ASR-inhibiting SCM in cementitious systems.
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Aves, Federico A Jr. « Utilizing Pulverized Glass as a Partial Replacement for Fine Aggregates in Cement Mortar ». International Journal of Advanced Research in Science, Communication and Technology, 30 juillet 2023, 981–86. http://dx.doi.org/10.48175/ijarsct-12339.

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Mortar plays a pivotal role in the construction industry, underscoring the significance of comprehending its quality and the intricate interplay of its mixture in shaping performance outcomes. The utilization of waste glass as an innovative alternative to conventional fine aggregates in mortar mixtures is instrumental in enhancing structural safety. In light of this, the present study is dedicated to investigating the efficacy of waste glass incorporation in bolstering both compressive and flexural strength. This inquiry delves into the intrinsic qualities and strength attributes of concrete mortars, scrutinizing the influence of pulverized waste glass content. The range of powdered waste glass inclusions encompasses 0%, 10%, 15%, 20%, 25%, 30%, 50%, and 60% by weight in relation to the sand component of the mortar mixture. The experimental design involves the fabrication of a total of 72 mortar cubes, where 48 specimens are earmarked for conducting assessments of compressive and flexural strength. Compressive and flexural strength evaluations are conducted on the mortar samples after 7, 14, and 28 days of both moist and water curing protocols. The outcomes of these tests unveil the effectiveness of incorporating powdered waste glass as an aggregate within mortar mixtures, particularly at the 25% replacement mark. Intriguingly, the investigation highlights that concrete mortars imbued with 25% waste glass content exhibit superior strength in comparison to the other examined samples. Additionally, the study underscores that the strength outcomes for replacements of 25% and 10% successfully meet the prescribed strength requirements for cement mortar outlined in accordance with ASTM standards
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Umoh, Romanus A., Uwemedimo F. Umoh, Imoh I. Johnny, Anwanabasi E. Udoh, Victor U. Anah, Omodot T. Umoh, Akwaowoh A. Elijah et Ndifreke S. Essienutin. « Phytopharmacognostic Standardization of the Leaves of Buchholzia coriacea Engler. (Capparidaceae) ». Journal of Complementary and Alternative Medical Research, 22 octobre 2020, 33–42. http://dx.doi.org/10.9734/jocamr/2020/v11i230183.

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Buchholzia coriacea Engl. is a medicinal plant belonging to the family Capparidaceae. It has antimicrobial, anthelmintic, antidiabetic and antihypercholesterol activities. The aim of this study was to employ the quality control parameters in the evaluation of the leaf of B. coriacea. The plant leaves were collected, air dried, pulverized and stored in a clean glass container. Standard procedures were carried out to obtain the microscopic features of the fresh and powdered samples, micromeritic, chemomicroscopy, fluorescence properties, soluble extractive values, moisture contents and ash values. The results of the microscopic study using fresh and powdered leaf samples revealed the presence of anomocytic stomata on the abaxial surface (hypostomatic) with mean length of 31.8 ± 0.6 cm. The cell shape was polygonal and straight anticlinal cell wall pattern. Results of the micromeritic properties of the powdered sample showed bulk volume of 31.00± 0.70cm, tapped volume of 25.1± 0.20 cm, bulk density of 0.32 ± 0.01g/m, tapped density of 0.39± 0.01g/ml, flow rate of 2.2 ± 0.08g/s, angle of repose of 26.1 ± 1.3 degrees, Carr’s index of 18.9± 1.35 %, Hausner’s ratio of 1.23 ± 0.02, pH of 8.0 when cold and 8.2 when hot for the powdered sample liquid extract. The results of the chemomicroscopic study revealed the presence of lignin, mucilage, calcium oxalate crystals, oil, calcium carbonate, but starch was absent. Results for the ethanol-soluble extractive value was 7 ± 0.00% , water-soluble extractive value was 14 ± 0.00% and methanol-soluble extractive value was 3 ± 0.00% for the powdered samples. Results for the moisture content was 10.3 ± 0.00% , total ash values was 6.3± 0.00% , acid-insoluble ash value was 1 ± 0.00% , water-soluble ash value was 3±0.00% and sulfated ash values was 7.5 ± 0.00% . In conclusion, the above evaluation methods and parameters there in could be used to identify and authenticate both the fresh and powdered crude drug product of Buchholzia coriacea.
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Umoh, Romanus A., Imoh I. Johnny, Anwanabasi E. Udoh, Nsima A. Andy, Affiong C. Essien, Inyang J. Udoh, Winnie E. Emeh et Otobong E. Umanah. « Micromorphological and Pharmacognostic Studies of Leaf and Stem of Solenostemon monostachyus P. Beauv (Lamiaceae) ». Journal of Complementary and Alternative Medical Research, 16 décembre 2021, 230–40. http://dx.doi.org/10.9734/jocamr/2021/v16i430312.

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Solenostemon monostachyus P. Beauv (Lamiaceae), it’s ethnomedical uses include anti-plasmodial, anti-pyretic, antiulcerogenic, antioxidant, anti-inflammatory and anti-nociceptive activities. The aim of this study was to employ the quality control parameters in the evaluation of the leaf and stem of Solenostemon monostachyus to aid in the identification and standardization of the medicinal plant. The plant leaves and stems were collected, identified, air-dried, pulverized and stored in separate glass containers. Standard procedures were employed to obtain the microscopic features of the fresh and powdered samples, micromeritic, chemomicroscopy, fluorescence properties, moisture contents, ash values and soluble extractive values. The results of the microscopic studies using fresh and powdered leaf samples revealed the presence of diacytic stomata on both the abaxial and adaxial surfaces (amphistomatic), with stomatal index of 27.9% and 14.8% respectively. The result of the micromeritics properties of the powdered leaf and stem samples showed angles of repose of 38.0o and 46.0o, Carr’s index of 23.7% and 32.5% and Hausner’s ratios of 1.3 and 1.5 respectively. Results for the moisture content, total, acid-insoluble and water-soluble ash values were 11.7%w/w, 13.7%w/w, 1.8%w/w and 9.4%w/w for the leaf and 13.3%w/w, 17.3%w/w, 1.8%w/w and 9.2%w/w for the stem respectively. Extractive values for water-soluble, methanol-soluble and ethanol-soluble were 26.5%w/w, 32.3%w/w, 14.5%w/w and 15.5%w/w, 15.8%w/w and 14.5%w/w for the leaf and stem respectively. Chemomicroscopy indicated the presence of lignin, calcium oxalate crystals and protein in the leaf and stem. The results obtained therefore could be used to establish pharmacopoeial standard for the fresh and powdered drug products of Solenostemon monostachyus, thus preventing adulteration.
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Umoh, Romanus A., Uwemedimo F. Umoh, Imoh I. Johnny, Omodot T. Umoh, Victor U. Anah, Anwanabasi E. Udoh, Akwaowoh A. Elijah et Blessing E. Andrew. « Phytopharmceutical Standardization of Leaves of Jatropha tanjorensis J. L. Ellis & ; Saroja. (Euphorbiaceae) ». Journal of Complementary and Alternative Medical Research, 17 octobre 2020, 1–10. http://dx.doi.org/10.9734/jocamr/2020/v11i230179.

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Jatropha tanjorensis J.L. Ellis & Saroja. (Euphorbiaceae) is a shrub commonly used as an edible vegetable and is also used as a tonic herb. The study was aimed to evaluate pharmacognostic parameters of Jatropha tanjorensis leaves. The plant leaves were collected, air-dried, pulverized and stored in a clean glass container. Standard procedures were employed to obtain the microscopic features of the fresh and powdered samples, micromeritic, chemomicroscopy, fluorescence properties, moisture content, ash values and soluble extractive values were also carried out. The results of the microscopic studies using the fresh and powered leaf samples revealed the presence of anomocytic, anomalous and paracytic stomata on the abaxial surface and anomocytic stomata on the adaxial surface. The plant sample also possessed unicellular trichomes. Results of micromeritic properties of the powdered samples show bulk volume of 38.67±0.7, tapped volume of 30.00±0.4, bulk density of 0.26±0.00, tapped density of 0.33±0.00, angle of repose of 350, Carr’s Index of 22.96±2.15, Hausner’s ratio of 1.27±0.03, pH of 7.51 and 7.52 when hot and cold respectively. Chemomicroscopy studies revealed the presence of lignin, mucilage, calcium oxalate crystals, starch and oil in the powdered leaf. Results for moisture contents was 18.33±0.01% w/w, total ash value was 9.33±0.00%w/w, acid-insoluble ash value was 0.67±0.01%w/w, water-soluble ash value was 4.0±0.00%w/w and sulfated ash value was 14±0.01%w/w. Results for ethanol-soluble extractive value was 15±0.00%w/w, methanol-soluble extractive value was 19±0.00%w/w and water-soluble extractive value was 27±0.01%w/w. In conclusion, the above evaluation and parameters could be used to establish pharmacopoeial standard of both fresh and powdered drug of Jatropha tanjorensis.
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