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Nanoscale Ceramics
Published in Debasish Sarkar, Nanostructured Ceramics, 2018
In consideration of basic electron transfer phenomenon, the material world can be classified in conductors, semiconductors, and insulators. However, a common platform encompasses their existence as metals, ceramics, polymers, or a combination of them. Thus, in consideration of these three, we can achieve any properties in the recent era, although their size controls the resultant appearance and properties of products or devices. Apart from the monolithic single-phase materials, a combination of material results in different composites including metal matrix composite, polymer matrix composite, ceramic matrix composite, or any other alteration. Despite two classic groups of materials like metals and polymers, herein, ceramics are preferentially targeted and discussed, in specific, in the form of nanostructured ceramics. In the perspective of book content, this section starts with a correlation with size and physical properties of materials to intellect and justify the synthesis of nanoscale materials. In the end, details of classification of ceramics are highlighted, and their probable use in modern burning issues like energy, environment, and health treatment is emphasized.
Monolithic Polymer Devices
Published in Agis F. Kydonieus, Controlled Release Technologies: Methods, Theory, and Applications, 2019
Theodore J. Roseman, Nate F. Cardarelli
Monolithic devices are usually prepared by either incorporating the solute within the monomeric material before polymerization and molding, extrusion, injection molding or by film casting.11,14,21–31 Alternatively, the matrix may be soaked in a solution of known solute concentration until the designated loading dose is achieved. Granular or porous matrices are manufactured utilizing tableting technology and have been prepared by direct compression of the mixture of the solute in a plastic matrix or by adding it to melted wax, granulating, and then compression.32–36 The geometry of the device is controlled by the dimensions of the mold, die, or film.
Conventional and 3D Printing Technology for the Manufacturing of Metal-Matrix Composite
Published in Suneev Anil Bansal, Virat Khanna, Pallav Gupta, Metal Matrix Composites, 2023
Rakesh Kumar, Santosh Kumar, Mohit Kumar, Gaurav Luthra
Metal matrix composites (MMCs) are high-performance lightweight materials with higher wear resistance and superior mechanical properties. These materials are made of two or more than two materials that are very cumbersome to obtain from a single material. In these material combinations, one works as a reinforcement and the other is a matrix. The reinforcement can be a discontinuous or continuous type and is utilized to alter the physical characteristics (thermal conductivity, resistance against wear, friction coefficient, etc.) (Callister 2001). The matrix is a monolithic and completely continuous material that distributes the stress utilized over it to the reinforcement constituents. It is a lightweight metal (Ti, Al, etc.) that exhibits a flexible base for reinforcement in structural use. Marsh, G. reported that currently the automobile industry is facing pressure to develop pollution-free and fuel-efficient motor vehicles. So, the industry has switched over to fiber-reinforced composites from costlier alloy materials to make its items lightweight and eco-friendly. The composition materials (composite material) are made from two (or more than two) combining materials and matrix of (Mg, Al, etc.), and are the principally accepted material for composites – although for high-temperature applications, Ti is also used as a matrix (Marsh 2003). Some authors reported that metal matrix composites provide many attractive advantages (higher strength, high stiffness, good wear resistance, and lightweight properties) over monolithic materials (Surappa 2003; Matthews and Rawlings 1994; Waku and Nagasawa 1994). Despite these, the toughness of MMCs is inferior as compared to monolithic metals and high cost. Conventional monolithic materials have drawbacks in attaining good combination of toughness, stiffness, strength, and density. To compensate these difficulties and to fulfill the increasing demand of present-day technology, composites are most encouraging materials of recent interest. Generally, MMCs give significantly enhanced properties such as high strength and high specific and better resistance against wear than to unreinforced alloys.
A novel erection technique of the L-shaped precast frames utilizing laminated metal plates
Published in Journal of Asian Architecture and Building Engineering, 2021
A significant number of experimental and numerical studies have been performed to examine the behavior of extended endplate connections for steel structures that were subjected to monotonic and cyclic loads (Tahir and Hussein 2008; Mureşan and Bâlc 2017; Ismail et al. 2016; Sumner and Murray 2002; Sofias, Kalfas, and Pachoumis 2014). These studies showed that steel connections can act as either fully rigid or semi-rigid connections, depending on the endplate thickness, bolt diameter, number of bolt rows and columns, bolt spacing, bolt grade, stiffeners, column and beam sizes, and yield strength of the steel. In this study, mechanical joints with fully restrained moment connections (which were developed to provide rapid and facile connections for composite precast columns) were employed. Here, a pair of steel plates was connected, offering monolithic column joints. Extensive full-scale assembly testing of the large columns that were designed to resist gravity and lateral loads, was performed to investigate how efficiently the vertical columns can form monolithic joints. The observed time required for this assembly using mechanical joints was less than 30 min. The proposed method can be used as an alternative for modular offsite construction for buildings and industrial plants subjected to heavy loads, thereby reducing the cost of construction compared to using steel structures.
Nonlinear finite element analysis of mechanical connections splicing precast columns with stiffened laminated metal plates
Published in Journal of Asian Architecture and Building Engineering, 2020
A benchmark experimental investigation was performed to explore the influence of column connections on the flexural capacity of the column in the study of Hu, Hong, and Park (2017) in which seven test specimens were manufactured and tested. Hu, Hong, and Park (2017) investigated the structural performance of a column connection stiffened with internal bolts and ribs. Table 1 (Hu, Hong, and Park 2017; Nzabonimpa and Hong 2018) summarizes the material properties of column plates, exterior bolts, rebars and steel columns used in the investigation. As described in the previous study by the authors (Hu, Hong, and Park 2017), a filler plate was not used for Specimen C2, in which nuts were threaded onto the rebars from the columns in the pits of the column plates. Nuts were also located in the counterbores of the column plates, and column plates were thick enough to completely accommodate the nuts. The column plates of Specimen C2, with a thickness of 45 mm, did not display any noticeable plate deformation. However, the column plates of Specimen C5, with thickness of 20 mm, were deformed. Specimen C6 was a steel-concrete composite column that was fabricated as a monolithic column. In Specimen C7, columns were spliced with high-yield-strength plates (Fy = 650 MPa) to explore the influence of high-yield-strength mechanical joint plates on the lateral flexural strength.
Preparation of a metal organic framework (MOF)-based monolithic column for the solid-phase extraction (SPE) of diosmetin from traditional Chinese medicine with determination by high-performance liquid chromatography (HPLC)
Published in Instrumentation Science & Technology, 2023
Shan Wang, Yamei Han, Jiangwei Chen, Ligai Bai, Hongyuan Yan, Haiyan Liu
The back pressure is an important index to evaluate the performance of monolithic columns. Figure 4A shows that the back pressures of both monolithic columns increased and decreased with the acetonitrile content of the mobile phase. Moreover, the back pressure of the monolithic column with added MOF was lower than for monolith without MOF. Hence, the addition of the MOF reduced the back pressure of the monolithic column.