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31.
Zeyu Zhao Jun Gao Yuqing Meng Kyle S. Brinkman Jianhua Tong 《Ceramics International》2021,47(8):11313-11319
The state-of-the-art protonic ceramic conductor BaZr0.8Y0.2O3-δ (BZY20) requires an extremely high sintering temperature (≥1700 °C) to achieve the desired relative density and microstructure necessary to function as a proton conducting electrolyte. In this work, we developed a cold sintering pretreatment assisted moderate-temperature sintering method for the fabrication of high-quality pure BZY20 pellets. BZY20 pellets with high relative density of ~94% were fabricated with a final sintering temperature of 1500 °C (200 °C lower than the traditional sintering temperature). A comparison with BZY20 control samples indicated that the proper amount of BaCO3 introduced on the BZY20 particle surface and the high green density achieved by cold sintering pretreatment were the main drivers for lowering the sintering temperature. The electrical conductivity measurement by electrochemical impedance spectroscopy showed that the as-prepared BZY20 pellets have a proton conductivity comparable to the state-of-the-art values. The cold sintering pretreatment outlined in this work has the potential to lower the sintering temperatures for similar types of protonic ceramic materials under consideration for a wide range of energy conversion and storage applications. 相似文献
32.
Theoretical Foundations of Chemical Engineering - The results of numerical modeling of the heat and mass transfer of drops during drying of a liquid under the conditions of... 相似文献
33.
Osipenko M. A. Kharitonov D. S. Makarova I. V. Romanovsky V. I. Kurilo I. I. 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(3):550-558
Protection of Metals and Physical Chemistry of Surfaces - The dependences of the protective properties of the anodic oxide coatings on the AD31 aluminum alloy surface modified with nitrates of... 相似文献
34.
Semiconductors - In conductors with a very low defect density, electrons at low temperatures collide mainly with the sample edges; therefore, the ballistic transport of charge and heat is... 相似文献
35.
Maryam Oroujeni Sara S. Rinne Anzhelika Vorobyeva Annika Loftenius Joachim Feldwisch Per Jonasson Vladimir Chernov Anna Orlova Fredrik Y. Frejd Vladimir Tolmachev 《International journal of molecular sciences》2021,22(5)
Radionuclide imaging of HER2 expression in tumours may enable stratification of patients with breast, ovarian, and gastroesophageal cancers for HER2-targeting therapies. A first-generation HER2-binding affibody molecule [99mTc]Tc-ZHER2:V2 demonstrated favorable imaging properties in preclinical studies. Thereafter, the affibody scaffold has been extensively modified, which increased its melting point, improved storage stability, and increased hydrophilicity of the surface. In this study, a second-generation affibody molecule (designated ZHER2:41071) with a new improved scaffold has been prepared and characterized. HER2-binding, biodistribution, and tumour-targeting properties of [99mTc]Tc-labelled ZHER2:41071 were investigated. These properties were compared with properties of the first-generation affibody molecules, [99mTc]Tc-ZHER2:V2 and [99mTc]Tc-ZHER2:2395. [99mTc]Tc-ZHER2:41071 bound specifically to HER2 expressing cells with an affinity of 58 ± 2 pM. The renal uptake for [99mTc]Tc-ZHER2:41071 and [99mTc]Tc-ZHER2:V2 was 25–30 fold lower when compared with [99mTc]Tc-ZHER2:2395. The uptake in tumour and kidney for [99mTc]Tc-ZHER2:41071 and [99mTc]Tc-ZHER2:V2 in SKOV-3 xenografts was similar. In conclusion, an extensive re-engineering of the scaffold did not compromise imaging properties of the affibody molecule labelled with 99mTc using a GGGC chelator. The new probe, [99mTc]Tc-ZHER2:41071 provided the best tumour-to-blood ratio compared to HER2-imaging probes for single photon emission computed tomography (SPECT) described in the literature so far. [99mTc]Tc-ZHER2:41071 is a promising candidate for further clinical translation studies. 相似文献
36.
Mauro Zammarano John R. Shields Isaac Leventon Ickchan Kim Shonali Nazare Andre Thompson Rick D. Davis Artur Chernovsky Matthew Bundy 《火与材料》2021,45(1):114-126
Herein, we describe a reduced‐scale test (“Cube” test), measuring the fire performance of specimens including a fire barrier (FB) and a flammable core material, which acts as the main fuel load. The specimen is intended to reproduce a cross‐section of a composite product where heat/mass transfer occurs primarily in a direction perpendicular to the FB. The Cube test procedure and benefits are discussed in this work by adopting residential upholstery furniture as an exemplary study. One flexible polyurethane foam, one polypropylene cover fabric, and 10 commercially available FBs were selected. They were used to compare the fire performance of FBs, measured in terms of peak of heat release rate, in the ASTM E1474‐14 standard test and the newly developed Cube test. Edge effects severely affected the performance of FBs in the ASTM E1474‐14 standard test but not in the Cube test. Furthermore, appropriate test conditions were determined in the Cube test to measure the so‐called “wetting point,” that is, the time and value of heat release rate measured when flammable liquid products were first observed on the bottom of the specimen. The relevance of the “wetting point” in terms of full‐scale fire performance and failure mechanism of FBs is discussed. 相似文献
37.
Golubev N. V. Ignat’eva E. S. Maurus A. A. Ziyatdinova M. Z. Lopatina E. V. Lorenzi R. Paleari A. Sigaev V. N. 《Glass and Ceramics》2021,77(11-12):415-418
Glass and Ceramics - The influence of Al2O3 as an additive and the heat-treatment regime on the luminescence spectra of gallate glass-ceramics was investigated. It is shown that its luminescence... 相似文献
38.
Mahantesh H. M. Nageswara Guptha M. Hema M. S. 《Wireless Personal Communications》2021,120(3):2349-2365
Wireless Personal Communications - 2In Software Defined Network based Internet of Things (SDN-IoT), the path selected for forwarding the packets as per rules, should be Quality of Service (QoS)... 相似文献
39.
Kruglikov S. S. Zagorskii D. L. Kolesnikov V. A. Doludenko I. M. Bedin S. A. 《Theoretical Foundations of Chemical Engineering》2021,55(5):942-951
Theoretical Foundations of Chemical Engineering - The effect of the electrolyte composition, mass-transfer conditions, pore diameter, interpore distance, and electric parameters on the formation of... 相似文献
40.
Felipe A. Perdomo Siti H. Khalit Claire S. Adjiman Amparo Galindo George Jackson 《American Institute of Chemical Engineers》2021,67(3):e17194
The SAFT-γ Mie group-contribution equation of state is used to represent the fluid-phase behavior of aqueous solutions of a variety of linear, branched, and cyclic amines. New group interactions are developed in order to model the mixtures of interest, including the like and unlike interactions between alkyl primary, secondary, and tertiary amine groups (NH2, NH, N), cyclic secondary and tertiary amine groups (cNH, cN), and cyclic methine-amine groups (cCHNH, cCHN) with water (H2O). The group-interaction parameters are estimated from appropriate experimental thermodynamic data for pure amines and selected mixtures. By taking advantage of the group-contribution nature of the method, one can describe the fluid-phase behavior of mixtures of molecules comprising those groups over broad ranges of temperature, pressure, and composition. A number of aqueous solutions of amines are studied including linear, branched aliphatic, and cyclic amines. Liquid–liquid equilibria (LLE) bounded by lower critical solution temperatures (LCSTs) have been reported experimentally and are reproduced here with the SAFT-γ Mie approach. The main feature of the approach is the ability not only to represent accurately the experimental data employed in the parameter estimation, but also to predict the vapor–liquid, liquid–liquid, and vapor–liquid–liquid equilibria, and LCSTs with the same set of parameters. Pure compound and binary phase diagrams of diverse types of amines and their aqueous solutions are assessed in order to demonstrate the main features of the thermodynamic and fluid-phase behavior. 相似文献