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81.
简要介绍了微波烧结的特点,对 Al2 O3 陶瓷的微波烧结过程进行了介绍和分析,并同常规烧结进行了对比实验,在此基础上得出了一些结论,为陶瓷微波烧结提供了实验依据 相似文献
82.
83.
利用电沉积硒气氛下后续退火的工艺制备出了高结晶质量的铜铟硒薄膜.通过X射线衍射、扫描电子显微镜、拉曼光谱、紫外-可见-近红外光谱和阻抗谱技术对退火后的铜铟硒薄膜进行表征,结果表明530 oC硒化退火后的铜铟硒薄膜具有四方的黄铜矿晶体结构,晶粒尺寸达到微米量级,光学带隙为0.98 eV,经过KCN溶液去除表面高导电性的铜硒化合物后铜铟硒薄膜的载流子浓度在1016 cm-3量级.利用硒化退火的铜铟硒薄膜作为光吸收层制备了结构为AZO/i-ZnO/CdS/CIS/Mo/glass的太阳能电池,在AM1.5光照条件下对其电流-电压特性测试后发现面积为0.2 cm2的电池可以达到0.96%的能量转换效率,并对限制电池效率的原因做出了初步的分析和讨论. 相似文献
84.
85.
86.
A scheme is proposed to controll the decoherence of
three-level rf-SQUID qubit with asymmetric potential by designing an
external electric circuit for superconductive flux qubit. The
results show that it may not only raise the gate speed but also extend
decoherence time for a three-level structure. 相似文献
87.
Minjeong Ji Hee Jung Ryu Hyeon-Man Baek Dong Min Shin Jeong Hee Hong 《Experimental & molecular medicine》2022,54(4):503
Rheumatoid arthritis (RA) is an autoimmune disease characterized by aggressive fibroblast-like synoviocytes (FLSs) and pannus formation. Various therapeutic strategies have been developed against inflammatory cytokines in RA in recent decades. Based on the migratory features of FLSs, we examined whether modulation of the migratory module attenuates RA severity. In this study, inflamed synovial fluid-stimulated FLSs exhibited enhanced migration and migratory apparatus expression, and sodium bicarbonate cotransporter n1 (NBCn1) was identified in primary cultured RA-FLSs for the first time. The NBC inhibitor S0859 attenuated the migration of FLSs induced with synovial fluid from patients with RA or with TNF-α stimulation. Inhibition of NBCs with S0859 in a collagen-induced arthritis (CIA) mouse model reduced joint swelling and destruction without blood, hepatic, or renal toxicity. Primary FLSs isolated from the CIA-induced mouse model also showed reduced migration in the presence of S0859. Our results suggest that inflammatory mediators in synovial fluid, including TNF-α, recruit NBCn1 to the plasma membrane of FLSs to provide dynamic properties and that modulation of NBCn1 could be developed into a therapeutic strategy for RA.Subject terms: Chemotaxis, Bone, Ion channel signalling, Rheumatoid arthritis, Drug development 相似文献
88.
Lei Ji Stefan Riese Alexander Schmiedel Marco Holzapfel Maximillian Fest Jrn Nitsch Basile F. E. Curchod Alexandra Friedrich Lin Wu Hamad H. Al Mamari Sebastian Hammer Jens Pflaum Mark A. Fox David J. Tozer Maik Finze Christoph Lambert Todd B. Marder 《Chemical science》2022,13(18):5205
Reversible conversion between excited-states plays an important role in many photophysical phenomena. Using 1-(pyren-2′-yl)-o-carborane as a model, we studied the photoinduced reversible charge-transfer (CT) process and the thermodynamic equilibrium between the locally-excited (LE) state and CT state, by combining steady state, time-resolved, and temperature-dependent fluorescence spectroscopy, fs- and ns-transient absorption, and DFT and LR-TDDFT calculations. Our results show that the energy gaps and energy barriers between the LE, CT, and a non-emissive ‘mixed’ state of 1-(pyren-2′-yl)-o-carborane are very small, and all three excited states are accessible at room temperature. The internal-conversion and reverse internal-conversion between LE and CT states are significantly faster than the radiative decay, and the two states have the same lifetimes and are in thermodynamic equilibrium.Reversible conversion between excited-states is key to many photophysical phenomena. We studied the equilibrium between LE and CT states by time-resolved and temperature-dependent fluorescence, fs- and ns-transient absorption, and LR-TDDFT calculations. 相似文献
89.
90.
Lai-Yu Lu Xiang-Rong Chen Guang-Fu Ji Xi-Jun Wang Jing Chang 《Molecular physics》2013,111(22):2373-2385
The structural, vibrational and thermodynamic properties of β-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (β–HMX) crystal have been studied using the isothermal-isobaric molecular dynamics (NPT-MD) simulations. The variations of cell volume, lattice constants and molecular geometry of solid β–HMX are presented and discussed at different pressure and temperature. It was found that the N–N bond is significantly lengthened with increasing temperature, which suggests that it is relevant to the initial decomposition. An abrupt change at 27 Gpa for the volume and internal geometrical parameters was observed. This is in good accord with the experimental observation that there is a phase transition at 27 GPa, which is clearly due to conformational change, not chemical reaction. The vibrational frequencies at ambient conditions agree well with experimental results, and the pressure/temperature-induced frequency shifts of these modes are discussed. Frequency discontinuity was also observed at pressure when the phase transition occurred. The Grüneisen parameter was obtained using the vibrational frequency. 相似文献