We report Ge23Sb7S70 chalcogenide ring resonators with up to 8 × 104 quality factors operating around 3.6 µm wavelength fabricated through e-beam lithography. Their rib waveguide geometry can be engineered t...
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The Na-22based radioactive tracer dilution (RTD) technique has been previously demonstrated for mass accounting in small quantities of clean molten salt for bench top testing. While the concept of RTD has proven to be...
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This study explores the potential of physically mixing individually targeted Doxorubicin (DOX)-loaded liposomes functionalized with folic acid (FA) and trastuzumab (TRA), combined with ultrasound (US) triggering, to e...
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Modern aircraft compression ignition engines that seek to achieve fuel-flexible operation require ignition-assisting devices to perform reliably. Many military propulsion systems, and unmanned aircraft in particular, ...
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Modern aircraft compression ignition engines that seek to achieve fuel-flexible operation require ignition-assisting devices to perform reliably. Many military propulsion systems, and unmanned aircraft in particular, can use hot surface energy addition to improve engine performance. An analysis of the thermomechanical stress behavior of hot surface ignition devices is therefore critical to ensure that they can satisfy new operational requirements. In this paper, a phenomenological heat-flux model is proposed to simulate heat generation inside a heating element. Two finite element analysis models are established using the proposed heat-flux model in order to characterize the transient thermomechanical behavior of an ignition assistant: a two-dimensional (2-D) axisymmetric model with an equivalent cylindrical heating element and a three-dimensional (3-D) solid model with realistic heating element geometry. The transient behavior of the ignition assistant is investigated at standard conditions by characterizing the temperature and thermal stress inside the device for various input voltages. The effect of the nonaxisymmetric heating element geometry on the temperature and thermal stress distribution is assessed. Furthermore, the 3-D ignition assistant model is used to analyze the thermomechanical behavior of an ignition device subjected to a combustion event inside a rapid compression machine. Multiple circumferential orientations of the heating element plane relative to the spray axis are investigated. Results demonstrate that the observed maximum principal stress depends significantly on heating element orientation.
The demand for sustainable, high-performance materials has led to increased interest in bio-based composites. However, optimizing the mechanical properties of such materials for engineering applications remains a chal...
The demand for sustainable, high-performance materials has led to increased interest in bio-based composites. However, optimizing the mechanical properties of such materials for engineering applications remains a challenge. This study addresses this gap by developing and characterizing an epoxy-based biocomposite reinforced with sugarcane bagasse particles, focusing on the influence of cyclic thermal treatment on its properties. The bagasse particles were chemically treated with 1 M NaOH to remove impurities, improve interfacial bonding with the epoxy matrix, and enhance the overall composite performance. The treated particles j were pulverized to 470 µm and incorporated into the epoxy matrix (0–20 wt%) using the hand layup method. The composites were divided into untreated and thermally treated groups, with the latter subjected to cyclic thermal treatment (100 °C for 3 h over 7 days). Mechanical, wear, and water absorption properties were evaluated, while fractured surface morphologies were analyzed using SEM. Results revealed that cyclic thermal treatment significantly enhanced the composites’ performance, with the 15 wt% heat-treated composite showing optimal properties: density of 1.102 g/cm3, flexural strength of 29.13 MPa, ultimate tensile strength of 103.50 MPa, impact strength of 3.49 kJ/m2, hardness of 64.70 HS, and wear indices of 0.034 mg. These findings demonstrate that alkali treatment and cyclic thermal treatment synergistically enhance the performance of bio-composites, making them suitable for diverse applications, including automotive, aerospace, and other engineering fields.
We present a statistically-based theoretical framework to describe the mechanical response of dynamically cross-linked semi-flexible polymer networks undergoing finite deformation. The theory starts from a statistical...
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Double-double (DD) lay-up is a new configuration strategy for the design of composite laminates, which allows the use of simplified stacking sequences that leads to potential advantages, such as improved manufacturabi...
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Two new high-entropy ceramics(HECs)in the weberite and fergusonite structures,along with the unexpected formation of ordered pyrochlore phases with ultrahigh-entropy compositions and an abrupt pyrochlore–weberite tra...
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Two new high-entropy ceramics(HECs)in the weberite and fergusonite structures,along with the unexpected formation of ordered pyrochlore phases with ultrahigh-entropy compositions and an abrupt pyrochlore–weberite transition,are discovered in a 21-component oxide *** the Gibbs phase rule allows 21 equilibrium phases,9 out of the 13 compositions examined possess single HEC phases(with ultrahigh ideal configurational entropies:~2.7kB per cation or higher on one sublattice in most cases).Notably,(15RE_(1/15))(Nb_(1/2)Ta_(1/2))O_(4) possess a single monoclinic fergusonite(C2/c)phase,and(15RE_(1/15))_(3)(Nb_(1/2)Ta_(1/2))_(1)O_(7) form a single orthorhombic(C222_(1))weberite phase,where 15RE_(1/15) represents Sc_(1/15)Y_(1/15)La_(1/15)Pr_(1/15)Nd_(1/15)Sm_(1/15)Eu_(1/15)Gd_(1/15)Tb_(1/15)Dy_(1/15)Ho_(1/15)Er_(1/15)Tm_(1/15) Yb_(1/15)Lu_(1/15).Moreover,a series of eight(15RE_(1/15))_(2+x)(Ti_(1/4)Zr_(1/4)Ce_(1/4)Hf_(1/4))_(2−2x)(Nb_(1/2)Ta_(1/2))_(x)O_(7) specimens all exhibit single phases,where a pyrochlore–weberite transition occurs within 0.75
作者:
Songshan ZengAndrew T.SmithKuangyu ShenLuyi SunPolymer Program
Institute of Materials Science and Department of Chemical&Biomolecular EngineeringUniversity of ConnecticutStorrsConnecticut 06269United StatesPresent Address:Macao Institute of Materials Science and Engineering(MIMSE)Zhuhai MUST Science and Technology Research InstituteFaculty of Innovation EngineeringMacao University of Science and TechnologyTaipa999078MacaoChina Polymer Program
Institute of Materials Science and Department of Chemical&Biomolecular EngineeringUniversity of ConnecticutStorrsConnecticut 06269United States
CONSPECTUS:Smart soft materials have one or more characteristics that can be significantly altered in convertible fashions by external stimuli,such as light,moisture,mechanical force,temperature,electric/magnetic fiel...
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CONSPECTUS:Smart soft materials have one or more characteristics that can be significantly altered in convertible fashions by external stimuli,such as light,moisture,mechanical force,temperature,electric/magnetic fields,pH,and so *** materials can lead to widespread application in multifunctional smart ***,various smart soft materials have been developed under the inspiration of the intriguing multiscale structures,adaptive mechanisms,and dynamic responses of natural life,with an aim to further design advanced material systems with novel,intriguing,and unprecedented properties.
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