Partial Replacement Of Ordinary Portland Cement In Concrete By Limestone Calcined Clay (Lc2),
2025
American University in Cairo
Partial Replacement Of Ordinary Portland Cement In Concrete By Limestone Calcined Clay (Lc2), Merna Abdelaziz
Theses and Dissertations
Limestone calcined clay (LC2) technique is a new approach that could address the environmental problem corelated with the construction industry due to its vital reliance on the ordinary Portland cement in its various applications. LC2 technique involves partial replacement of the OPC in concrete by limestone and calcined kaolinite clay with a ratio of 1:2 respectively. The main advantage of this technique is its high applicability due to its direct application on site. This study investigated the applicability of incorporating the LC2 technique in the construction industry. Three replacement percentages of OPC by LC2 in concrete were explored, which are …
Viscoelastic Protective Armor Liners And Protective Armor,
2025
Missouri University of Science and Technology
Viscoelastic Protective Armor Liners And Protective Armor, Fatih Dogan, Cody Thomas, Catherine Johnson
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Microstructural, Oxidation, And Mechanical Behavior Of Nbti-Based Refractory Alloys With 5 To 10 Pct Co, Cr, And Ni Additions,
2025
Case Western Reserve University
Microstructural, Oxidation, And Mechanical Behavior Of Nbti-Based Refractory Alloys With 5 To 10 Pct Co, Cr, And Ni Additions, Tae Kyong John Kim, Jennifer Carter
Faculty Scholarship
NbTi-based refractory alloys with additions of Co, Cr, and Ni represent an interesting medium-entropy alloy system with potential for protective oxide film formation, high strength, and ductility. This study investigates the microstructural evolution, oxidation behavior, and mechanical properties of NbTi-based alloys containing 5 to 10 at. pct Co, Cr, and Ni. CALPHAD predictions suggest that this composition range can be heat treated to obtain a predominantly body-centered cubic matrix phase. Mechanical properties, including microhardness, yield strength, maximum strength, and specific strength are evaluated through isothermal compression tests conducted between room temperature and 800 °C. The oxidation kinetics of these alloys …
Research Of Horse Oil Based Shampoo For Fine Hair Involving Local Oils And Enzyms Transesterification,
2025
Tashkent Institute of Chemical Technology, Tashkent, Uzbekistan
Research Of Horse Oil Based Shampoo For Fine Hair Involving Local Oils And Enzyms Transesterification, Sherzod Y. Rakhmanov, Madina O. Khaydarova, Bonu G. Аrislonboyeva, Nilufar A. Khaydarova, Dilshod P. Rakhimov
CHEMISTRY AND CHEMICAL ENGINEERING
Currently, there are many shampoos, balms and various hair masks. Shampoo-tonics have also been introduced into production, providing temporary coloring without damaging the hair structure. In this research work, we set ourselves the task of conducting a study of a shampoo for soft hair that provides durability, granularity and shine to hair by transesterifying horse oil with the enzyme lipase and the surfactant sodium lauryl sulfate. Depending on the type of shampoo, we conducted a scientific study using the following experimental method. To add horse oil to the shampoo formula, we re-esterified mixtures of horse oil and sunflower oil in …
Effect Of Desorption On Photocatalytic Decomposition Of Methylene Blue Using Materials From Solid Wastes Of Production Of Molybdenum Oxides (Vi) And Titanium Dioxide,
2025
Tashkent Institute of Chemical Technology, Tashkent, Uzbekistan
Effect Of Desorption On Photocatalytic Decomposition Of Methylene Blue Using Materials From Solid Wastes Of Production Of Molybdenum Oxides (Vi) And Titanium Dioxide, Dilshoda R. Tursunova, Shahlo Sh. Daminova, Rafael A. Nusretov, Ayipbergen Shiknazarov, Zuhra Ch. Kadirova
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the work is to obtain and characterize a composite photocatalyst based on the spent catalyst of the Shurtan Mining and Chemical Combine based on titanium dioxide and molybdenum-containing waste of the Almalyk Mining and Metallurgical Combine and to identify factors influencing the process of photocatalytic decomposition of methylene blue in solution under the action of UV light. In this work, we studied the kinetics of photocatalytic decomposition of methylene blue on the surface of materials obtained from technogenic solid waste, which were thermally activated at a temperature of 600 ° C. It was found that desorption plays …
X-Ray Photoelectron Spectroscopy Investigation Of Surface Changes In Chalcocite And Enargite Minerals Following Oxidation Treatment,
2025
Uzbek-Japan Innovation Center of Youth, National University of Uzbekistan, Tashkent, Uzbekistan, Kyushu University, Fukuoka, Japan
X-Ray Photoelectron Spectroscopy Investigation Of Surface Changes In Chalcocite And Enargite Minerals Following Oxidation Treatment, Berdakh T. Daniyarov, Miki Hajime, Baxtigul Y. Ruzieva, Shahlo Sh. Daminova
CHEMISTRY AND CHEMICAL ENGINEERING
Copper sulfide minerals, such as chalcocite (Cu₂S) and enargite (Cu₃AsS₄), are important sources of copper, which has wide applications in electronics, energy, and other industries. These minerals are traditionally processed using flotation methods, which are one of the most effective ways to extract copper from sulfide ores. However, the success of flotation of copper sulfides, such as chalcocite and enargite, strongly depends on changes in their surface properties, such as hydrophobicity or hydrophilicity, which can be modified by various chemical reagents. To further understand the impact of these chemical reagents on chalcocite and enargite minerals, X-ray photoelectron spectroscopy (XPS) was …
Synthesis And Study Of Complex Compounds With 1,3,4-Oxadiazole Derivatives Based On Ammonium Vanadate,
2025
Tashkent State Dental Institute, Tashkent, Uzbekistan
Synthesis And Study Of Complex Compounds With 1,3,4-Oxadiazole Derivatives Based On Ammonium Vanadate, Mehribon A. Pirimova, Shaxnoza A. Kadirova, Abduhakim A. Ziyayev
CHEMISTRY AND CHEMICAL ENGINEERING
This research work examines the synthesis, structure and properties of ammonium vanadate complex compounds based on 1,3,4-oxadiazole derivatives. Competing donor centers in coordination, electronic and geometric structures of the ligand molecule were studied based on quantum chemical calculations using the Gaussian09 LanL2DZ software package. Among the ligands, 2-carboxymethylthio-5-phenyl-1,3,4-oxadiazole ligand has been shown to have more competitive donor atoms than other ligands.
Structural Features And Morphology Of Biodegradable Composites Based On Polylactide And Corn Starch,
2025
State Technical University of Gomel, Gomel, Belarus
Structural Features And Morphology Of Biodegradable Composites Based On Polylactide And Corn Starch, Eygeniy N. Poddenezhny, Andrei A. Boiko, Ekaterina E. Trusova, Viktor M. Shapovalov
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the work was to study the morphology and structural features of biodegradable composites based on polylactide, filled with corn starch formed by extrusion method. The characteristics of the obtained materials were investigated by scanning electron microscopy, X-ray diffraction, IR spectroscopy. It was established that the presence of polyethylene glycol PEG–4000 as a plasticizer and surfactant – glycerin monostearate in the initial mixture leads to the formation of a nonporous heterogeneous system, in which starch particles are statistically distributed in the matrix. The starch concentration in the composite varied from 20 to 55 wt. %. When the starch …
Influence Of Thermal Cycling On The Resistance Of Bismuth Cuprates Synthesized Using Solar Energy,
2025
Materials Science Institute, Tashkent, Uzbekistan
Influence Of Thermal Cycling On The Resistance Of Bismuth Cuprates Synthesized Using Solar Energy, Dilbara Dj. Gulamova, Sirojiddin Z. Mirzaev, Sirojiddin Kh. Bobokulov, Elyor B. Eshonkulov, Grigor I. Mamniashvili
CHEMISTRY AND CHEMICAL ENGINEERING
A bulk superconducting ceramic synthesized using solar technology exhibits a sharp increase in resistance from zero to approximately 160Ω at 250 K. Four thermal cycling tests in the range of 79-360 K revealed a tendency for the temperature transition interval to narrow and a comparatively sharp jump at 290 K, suggesting a superconducting transition. The effect of stress concentration at grain boundaries during four cycles leads to an increase in the superconducting transition temperature due to the cumulative rise in stress and pinning force. The assumption that these effects are caused by superconducting homologous phases is based on the manifestation …
The Effect Of B2o3 On The Structure And Properties Of The Glasses Of The Na2o–Cao–Mgo–Sio2–P2o5 System,
2025
Belarusian State Technological University, Minsk, Belarus
The Effect Of B2o3 On The Structure And Properties Of The Glasses Of The Na2o–Cao–Mgo–Sio2–P2o5 System, Mihail V. Dyadenko, Ivan A. Levitskiy, Irina I. Kurilo, Alexander S. Glinskii
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this work was to study the effect of boron oxide on the physico-chemical and technological properties of glasses of the Na2O–CaO–MgO–SiO2–P2O5 system. The study of crystallization ability, density, the temperature of the onset of softening, as well as the chemical stability of experimental glasses modified with boron oxide, made it possible to indirectly assess their ability to dissolve in aqueous solutions and show bioactive properties. The article presents the results of the influence of B2O3 on the viscosity of the studied glasses and the value of their …
Research Of The Decomposition Process Of Unenriched Phosphate Raw Materials Of Central Kyzylkum With Nitric And Sulfuric Acids,
2025
Tashkent Institute of Chemical Technology, Tahskent, Uzbekistan
Research Of The Decomposition Process Of Unenriched Phosphate Raw Materials Of Central Kyzylkum With Nitric And Sulfuric Acids, Husan A. Zikirov, Ruslan Ch. Yorbobaev, Kholtura Ch. Mirzakulov
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the research is to establish the optimal technological parameters of the process of decomposition of unenriched phosphate raw materials of the Central Kyzylkum nitric and sulfuric acid for processing complex nitrogen-phosphorus fertilizers, to study the chemical composition, rheological properties. The coefficient of decomposition of unenriched phosphate raw materials, pH of acid pulp depending on various ratios and the total rate of nitric-sulfuric acid, as well as S:L of the environment are determined. The chemical and mineralogical composition of nitrosulphophosphate fertilizers formed after drying the ammoniated pulp are established.
Biobased Acrylate Composites With Enhanced Strength For Additive Manufacturing,
2025
Chapman University
Biobased Acrylate Composites With Enhanced Strength For Additive Manufacturing, Nicole Wagner, Joseph Mcwherter
Engineering Faculty Articles and Research
With the expanding use of polymers in additive manufacturing, sustainable resins for use in vat photopolymerization are required to reduce their environmental impact. One promising approach to achieve this is to incorporate biobased fillers that replace the acrylates in photopolymer resins as ‘green’ alternatives. In this study, photopolymer composites consisting of a methacrylate resin with varying calcium carbonate powder content between 0 and 50 wt.% were investigated. A digital light processing technique was used to fabricate tensile test specimens for mechanical testing. Good printability, dimensional accuracy, and good interlayer adhesion were observed for composite resin formulations that incorporated calcium carbonate …
Selective Leaching Of Rare Earth Elements From Complex Rare Earth Ore Using Deep Eutectic Solvents,
2025
Montana Technological University
Selective Leaching Of Rare Earth Elements From Complex Rare Earth Ore Using Deep Eutectic Solvents, Frank Agyemang, Mehran Saddat, Zainab Nasrullah, Richard Ladouceur
Metallurgical & Materials Engineering
Rare earth elements (REEs) are valuable for various modern technological applications, including metallurgy, machine building, radio electronics, instrument engineering, nuclear engineering, and manufacturing. The extraction and separation of rare earth elements (REEs) from their complex ores is challenging due to their distinct physical and chemical properties, contributing to their market scarcity. At present, REE recovery utilizes traditional pyro- or hydrometallurgical processes. The overall process in the recovery and separation of individual elements from complex REE systems suffers from high energy demands and the use of many hazardous chemicals that negatively impact the environment. With the growing trend toward a circular …
Process Intensification By Resonant Vibratory Mixing For The Recyclable Samarium - Cobalt Magnets After Chemical Leaching With Deep Eutectic Solvents,
2025
Montana Technological University
Process Intensification By Resonant Vibratory Mixing For The Recyclable Samarium - Cobalt Magnets After Chemical Leaching With Deep Eutectic Solvents, Zainab Nasrullah, Frank Agyemang, Mehran Saddat, Richard Ladouceur
Metallurgical & Materials Engineering
To sustain the circular economy, defense applications, and other renewable technologies, recycling rare earth elements (REEs) and other critical elements from their secondary resources is important. This cause has resulted in rigorous research and development for viable extraction and separation of REEs. Previously, Sm-Co recycling has been done with technologies, which fall under the categories of pyrometallurgy, physical separation, and hydrometallurgy. All these methods have limitations associated with energy, cost, and environment. Reportedly, the chemical leaching technology has successfully recovered and separated Sm-Co. Still, it has limitations associated with slow mass transfer and leaching kinetics, and there is a need …
Simulation-Based Models For Postearthquake Response: A Survey And Research Directions,
2025
Missouri University of Science and Technology
Simulation-Based Models For Postearthquake Response: A Survey And Research Directions, Abhijit Gosavi, Lauryn A. Spearing, Lesley H. Sneed
Engineering Management and Systems Engineering Faculty Research & Creative Works
Computer simulation is increasingly being used by emergency planners as a tool to improve disaster response given that it can model real-world scenarios, such as earthquakes. Although there has been an increase in simulation research focused on disaster response, much of this literature is from disparate fields and across disaster scenarios. To bridge this gap, this paper surveys simulation-based models for post-earthquake response from the year 2000 onward. Advantages of simulation over closed-form statistical models are discussed. Three main subproblems in post-earthquake response models are explored: (1) service distribution (e.g., food, water), (2) infrastructure restoration (at the building and transportation …
Rheology And Early-Age Structure Development In Binary And Ternary Blends Modified With Novel Graphene Types,
2025
Missouri University of Science and Technology
Rheology And Early-Age Structure Development In Binary And Ternary Blends Modified With Novel Graphene Types, Sahil Surehali, Collin Gustafson, Sayee Srikarah Volaity, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath
Materials Science and Engineering Faculty Research & Creative Works
Interest in the use of graphene to enhance the properties of cementitious materials is growing, but major impediments in implementation are the cost of graphene and changes in binder rheology attributable to these nanomaterials. This study explores the influence of novel, cost-effective, environment-friendly, and mass-producible graphene on the rheology and early-age structure development of cementitious binders. Two novel graphene types—fractal graphene (FG) and reactive graphene (RG)—are used in plain cement mixtures as well as those containing 30 % (by mass) of fly ash and/or limestone powder, at low dosages of ≤0.02 % by mass of binder. The early- and later-age …
Influence Of Temperature, Oxygen Partial Pressure, And Microstructure On The High-Temperature Oxidation Behavior Of The Sic Layer Of Triso Particles,
2025
Missouri University of Science and Technology
Influence Of Temperature, Oxygen Partial Pressure, And Microstructure On The High-Temperature Oxidation Behavior Of The Sic Layer Of Triso Particles, Visharad Jalan, Adam Bratten, Meng Shi, Tyler Gerczak, Haiyan Zhao, Jonathan D. Poplawsky, Xiaoqing He, Grant Helmreich, Haiming Wen
Materials Science and Engineering Faculty Research & Creative Works
Tri structural isotropic (TRISO)-coated fuel particles are designed for use in high-temperature gas-cooled nuclear reactors, featuring a structural SiC layer that may be exposed to oxygen-rich environments over 1000 °C. Surrogate TRISO particles were tested in 0.2–20 kPa O2 atmospheres to observe the differences in oxidation behavior. Oxide growth mechanisms remained consistent from 1200–1600 °C for each PO2, with activation energies of 228 ± 7 kJ/mol for 20 kPa O2 and 188 ± 8 kJ/mol for 0.2 kPa O2. At 1600 °C, kinetic analysis revealed a change in oxide growth mechanisms between 0.2 and 6 kPa O2. In 0.2 kPa …
Thermally Stimulated Stiffening And Fly Ash's Alkaline Activation By Ca(Oh)2 Addition Facilitates 3d-Printing,
2025
Missouri University of Science and Technology
Thermally Stimulated Stiffening And Fly Ash's Alkaline Activation By Ca(Oh)2 Addition Facilitates 3d-Printing, Xiaodi Dai, Sharu Bhagavathi Kandy, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Torben Gaedt, Samanvaya Srivastava, Gaurav Sant
Materials Science and Engineering Faculty Research & Creative Works
3D-printing could offer substantial benefits to the construction industry including the fabrication of customized/bespoke components, eliminating formwork, and reducing material waste. Despite these advantages, control of the pumpability, extrudability, and buildability of 3D-printed concrete (3DPC) remains challenging. This study demonstrates how the use of fly ash (FA) enables enhanced thermal stiffening, and rapid alkali-activation in the presence of portlandite (Ca(OH)2, CH). In general, blends of CH and FA exhibit less structural build-up at low temperatures, but upon reaching a trigger temperature of 75 °C, these blends achieve rapid stiffening, at rates of ∼800 Pa/s. The rapid stiffening arises from the …
Impurity Behavior In Cast Copper Anodes: Implications For Electrorefining In A Circular Economy,
2025
Missouri University of Science and Technology
Impurity Behavior In Cast Copper Anodes: Implications For Electrorefining In A Circular Economy, Agustin Morales-Aragon, Daniel Sánchez-Rodas, Guillermo Ríos, Michael S. Moats
Materials Science and Engineering Faculty Research & Creative Works
The behavior of impurities in cast copper was investigated to simulate production with increased utilization of secondary sources within the framework of a circular economy. The incorporation of impurities, particularly Ni, Sn, and Sb, from recycled Cu may significantly impact the electrorefining process. In this study, commercial anodes were doped with Ni, Sn, and Sb concentrations of 2500–6500 g/t, 300–900 g/t, and 450–950 g/t, respectively. Anode concentrations of Pb and Bi were maintained at 1000 g/t and 350 g/t, respectively. As concentrations were examined at two levels, 860 or 1700 g/t, depending on the commercial anode used to create the …
Effects Of Gypsum And Limestone On Early-Age Hydration And Strength Optimization In Belite Calcium Sulfoaluminate Cement,
2025
Missouri University of Science and Technology
Effects Of Gypsum And Limestone On Early-Age Hydration And Strength Optimization In Belite Calcium Sulfoaluminate Cement, Sai Akshay Ponduru, Bryan K. Aylas-Paredes, Taihao Han, Advaith Neithalath, Narayanan Neithalath, Gaurav Sant, Aditya Kumar
Materials Science and Engineering Faculty Research & Creative Works
Belite calcium sulfoaluminate cement (CSAB), an alternative to Portland cement, exhibits excellent strength at both early and later ages. However, due to its high belite content, the carbon reduction from this type of cement is not sufficient when compared to other alternative cements. To further enhance CSAB's sustainability, this study investigates the performance of CSAB when partially replaced by low-carbon mineral additives (i.e., limestone and gypsum). The primary objective is to identify the optimal mixture design by incorporating gypsum and limestone to formulate a sustainable binder that maintains high compressive strength. The CSAB is replaced (with both additives) by up …
