| 1. |
- Ding, Haoming, et al.
(author)
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Progress in Structural Tailoring and Properties of Ternary Layered Ceramics
- 2023
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In: Journal of Inorganic Materials. - : SCIENCE PRESS. - 1000-324X. ; 38:8, s. 845-884
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Research review (peer-reviewed)abstract
- MAX/MAB phases are a series of non-van der Waals ternary layered ceramic materials with a hexagonal structure, rich in elemental composition and crystal structure, and embody physical properties of both ceramics and metals. They exhibit great potential for applications in extreme environments such as high temperature, strong corrosion, and irradiation. In recent years, two-dimensional (2D) materials derived from the MAX/MAB phase (MXene and MBene) have attracted enormous interest in the fields of materials physics and materials chemistry and become a new 2D van der Waals material after graphene and transition metal dichalcogenides. Therefore, structural modulation of MAX/MAB phase materials is essential for understanding the intrinsic properties of this broad class of layered ceramics and for investigating the functional properties of their derived structures. In this paper, we summarize new developments in MAX/MAB phases in recent years in terms of structural modulation, theoretical calculation, and fundamental application research and provide an outlook on the key challenges and prospects for the future development of these layered materials.
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| 2. |
- Cha, Eunjung, 1985, et al.
(author)
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Optimization of Channel Structures in InP HEMT Technology for Cryogenic Low-Noise and Low-Power Operation
- 2023
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In: IEEE Transactions on Electron Devices. - 1557-9646 .- 0018-9383. ; 70:5, s. 2431-2436
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Journal article (peer-reviewed)abstract
- We report the impact from channel composition on the cryogenic low-noise performance at low dc power for a 100-nm gate-length InGaAs-InAlAs-InP high-electron mobility transistor (HEMT). Two indium (In) channel compositions, 65% and 80%, were studied by dc and RF characterization at 300 and 5 K. For the cryogenic low-noise optimization, it was important to increase the transconductance to gate–source capacitance ratio in the weak inversion region implying that a higher maximum cutoff frequency in the HEMT does not guarantee lower noise. The HEMT noise performance was obtained from noise measurements in a hybrid three-stage 4–8-GHz ( $\textit{C}$ -band) low-noise amplifier (LNA) down to 300- $\mu$ W dc power dissipation. While the HEMT LNA noise performance for both the channel compositions at 300 K was found to be comparable, the HEMT LNA at 5 K with 65% In channel showed a minimum noise temperature of 1.4 K, whereas the noise temperature in the HEMT LNA with 80% In channel HEMTs increased to 2.4 K. The difference in the noise became more pronounced at reduced dc power dissipation. The ultralow dc power of 300 $\mu$ W demonstrated for a cryogenic $\textit{C}$ -band LNA with an average noise temperature of 2.9 K and 24-dB gain is of interest for future qubit read-out electronics at 4 K.
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| 3. |
- Li, Junjie, 1995, et al.
(author)
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Optimization of InGaAs Channel for Cryogenic InP HEMT Low-Noise Amplifiers
- 2023
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Conference paper (other academic/artistic)abstract
- The noise temperature was measured for InP HEMTs in cryogenic low-noise amplifiers (LNAs) with channel indium content varied from 53% to 70%. The Hall measurements for all the epitaxial structures and dc characteristics of InP HEMTs were characterized. The 4–8 GHz LNA with lattice-matched channel InP HEMTs has the highest noise temperature at 5 K. The LNAs with 60% and 70% channel exhibited similar noise of 1.4 K at the optimum noise bias at 5 K. The 60% channel InP HEMT showed the lowest drain noise temperature with 10.5 mW power consumption and the lowest LNA noise at low power with 3.3 K for 100 μW. The results indicate that there is an optimum indium channel composition for InP HEMTs in cryogenic LNAs.
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| 4. |
- Li, Suyang, et al.
(author)
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Highly homogeneous bimetallic core-shell Au@Ag nanoparticles with embedded internal standard fabrication using a microreactor for reliable quantitative SERS detection
- 2023
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In: Materials Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1537. ; 7:6, s. 1100-1109
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Journal article (peer-reviewed)abstract
- Bimetallic gold core-silver shell (Au@Ag) surface-enhanced Raman scattering tags draw broad interest in the fields of biological and environmental analyses. Herein, an efficient hybrid microfluidic chip was designed to prepare uniform Au@Ag core-shell nanoparticles, and DTNB was used as the internal standard tag molecule to prepare Au@DTNB@Ag for SERS detection. Homogeneous core-shell nanoparticles with a particle size of 90 nm were prepared by mixing a silver precursor and a gold core in a microfluidic chip. The relative standard deviation (RSD) of the particle size distribution was close to 10%, and the detection limit of 4-MBA was as low as 10-10 M. In order to solve the influence of SERS signal fluctuation, a uniform Au@DTNB@Ag core-molecule-shell structure was synthesized in a microfluidic chip, and the characteristic peak of the analyte was corrected by the relative intensity of the DTNB characteristic peak (1335 cm−1). The experimental results showed that the SERS detection was achieved with high reproducibility, and the SERS peak intensity had a good linear correlation with the concentration. The homogeneous SERS substrate prepared using a microfluidic chip has potential for sensitive and reliable detection of environmental chemical contaminants.
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| 5. |
- Qiao, Xinyu, et al.
(author)
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Effects of ethanol pretreatment on osteogenic activity and off-flavors in blue mussel (Mytilus edulis L.) enzymatic hydrolysates
- 2023
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In: Food Research International. - : Elsevier. - 0963-9969 .- 1873-7145. ; 167
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Journal article (peer-reviewed)abstract
- Aquatic protein hydrolysates have many biological activities, but the off-flavor seriously decreases their commercial acceptability. Therefore, it is important to invest in finding an effective deodorization of aquatic hydrolysates that do not affect activities. In this study, ethanol pretreatment of mussel was applied to establish a new method to deodorize the blue mussel (Mytilus edulis L.) hydrolysates. LC-MS and GC–MS analysis results showed that 87.34% of fatty acids, 83.94% of aldehydes, most volatile flavor compounds including aldehydes, ketones, alcohols, acids, and hydrocarbons were decreased after ethanol pretreatment. Besides, it was found that the enzymatic hydrolysates of mussel with or without ethanol pretreatment showed high osteogenic activity, which induced an increase of 33.65 ± 4.36% and 31.77 ± 5.45% in MC3T3-E1 cell growth. These results suggest that ethanol pretreatment has beneficial potential for improving the flavor aspects of blue mussel peptides which may have the potential to stimulate bone regeneration and formation.
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| 6. |
- Yao, Zehan, et al.
(author)
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Flexible supercapacitors based on vertical graphene/carbon fabric with high rate performance
- 2023
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In: Applied Surface Science. - : Elsevier BV. - 0169-4332. ; 610
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Journal article (peer-reviewed)abstract
- Vertical graphene (VG) is a remarkable electrode material for supercapacitors due to its large specific area, open channel structures, and numerous exposed edges with high electrochemical activity. However, flexible supercapacitors with high rate performance based on VG have yet to be investigated. Here, we report flexible supercapacitors based on VG, carbon fabric (CF) current collector, and H2SO4 gel polymer electrolyte. VG/CF presents an exceptional electrochemical performance in H2SO4 compared with other aqueous and liquid ion electrolytes. The flexible VG/CF supercapacitor demonstrates a 73% capacitance retention after increasing the charge-discharge rate by 200 times from 0.1 mA cm−2 to 20 mA cm−2. This high rate performance facilitates a high power density of 13.2 mW cm−2 with an energy density of 86.6 μWh cm−2. Furthermore, the electrochemical performances remain mostly unchanged after long-term charge-discharge cycles and mechanical bending. Our results demonstrate a flexible VG/CF supercapacitor with outstanding rate performance and stability for innovative high power energy and electronic devices.
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| 7. |
- Zeng, Yin, 1996, et al.
(author)
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100-μW Cryogenic HEMT LNAs for Quantum Computing
- 2023
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In: 2023 18th European Microwave Integrated Circuits Conference, EuMIC 2023. ; , s. 71-74
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Conference paper (peer-reviewed)abstract
- Low-power cryogenic LNAs are of interest in future large-scale quantum computing where available cooling capability limits the number of active circuits. We present a comparison of small-signal noise models between two different 100-nm gate-length InP HEMTs at 4 K. The HEMTs were tested in the first stage of a three-stage hybrid cryogenic 4-6 GHz LNA operating at 100-W dc power. The better performing cryogenic LNA exhibited 23.2 dB average gain, 2.0 K average noise temperature, and-55dBm input 1-dB compression point. The enhanced LNA performance was attributed to the improved transconductance of the first-stage HEMT. To the authors' knowledge, this is the lowest noise reported to date for a 100-W transistor-based LNA aimed for qubit readout.
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