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871.
872.
Simulation of dielectric resonator for a high-T_c radio frequency superconducting quantum interference device 下载免费PDF全文
Nowadays,the high-critical-temperature radio frequency superconducting quantum interference device (high-T c rf SQUID) is usually coupled to a dielectric resonator that is a standard 10 × 10 × 1 mm 3 SrTiO 3 (STO) substrate with a YBa 2 Cu 3 O 7-δ (YBCO) thin-film flux focuser deposited on it.Recently,we have simulated a dielectric resonator for the high-T c rf SQUID by using the ANSOFT High Frequency Structure Simulator (ANSOFT HFSS).We simulate the resonant frequency and the quality factor of our dielectric resonator when it is unloaded or matches a 50-impedance.The simulation results are quite close to the practical measurements.Our study shows that ANSOFT HFSS is quite suitable for simulating the dielectric resonator used for the high-T c rf SQUID.Therefore,we think the ANSOFT HFSS can be very helpful for investigating the characteristics of dielectric resonators for high-T c rf SQUIDs. 相似文献
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Yonggang Gao Lin Gu Yusheng Qin Xianhong Wang Fosong Wang 《Journal of polymer science. Part A, Polymer chemistry》2012,50(24):5177-5184
Low‐molecular weight oligo(carbonate‐ether) diols are important raw materials for polyurethane formation, which with tunable carbonate unit content (CU) may endow new thermal and mechanical performances to polyurethane. Herein, facile synthesis of oligo(carbonate‐ether) diols with number average molecular weight (Mn) below 2000 g mol?1 and CU tunable between 40% and 75% are realized in high activity by immortal copolymerization of CO2/propylene oxide (PO) using zinc‐cobalt double metal cyanide complex (Zn‐Co‐DMCC) in the presence of sebacic acid (SA). Mn of the oligomer is in good linear relationship to the mole ratio of PO and SA (PO/SA) and hence can be precisely controlled by adjusting PO/SA. Besides, the molecular weight distribution is quite narrow due to the rapid reversible chain transfer in the immortal copolymerization. High pressure and low temperature are favorable for raising CU. In all the reactions, the weight fraction of propylene carbonate (WPC) can even be controlled as low as 2.0 wt %, and the catalytic activity of Zn‐Co‐DMCC is above 1.0 kgg?1 cat. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
875.
Haiyang Gao Xiaofang Liu Lixia Pei Qing Wu 《Journal of polymer science. Part A, Polymer chemistry》2010,48(5):1113-1121
Two bis(β‐ketoamino)copper [ArNC(CH3)CHC(CH3)O]2Cu ( 1 , Ar = 2,6‐dimethylphenyl; 2 , Ar = 2,6‐diisopropylphenyl) complexes were synthesized and characterized. Homo‐ and copolymerizations of methyl acrylate (MA) and 1‐hexene with bis(β‐ketoamino)copper(II) complexes activated with methylaluminoxane (MAO) were investigated in detail. MA was polymerized in high conversion (>72%) to produce the syndio‐rich atactic poly(methyl acrylate), but 1‐hexene was not polymerized with copper complexes/MAO. Copolymerizations of MA and 1‐hexene with 1 , 2 /MAO produced acrylate‐enriched copolymers (MA > 80%) with isolated hexenes in the backbone. The calculation of reactivity ratios showed that r(MA) is 8.47 and r(hexene) is near to 0 determined by a Fineman‐Ross method. The polymerization mechanism was discussed, and an insertion‐triggered radical mechanism was also proposed. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1113–1121, 2010 相似文献
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<正>A novel polyester containing ferrocenyl was prepared by low-temperature interface polycondensation of 1,1'-ferrocenedicarboxylic acid chloride with 4-(4-hydroxyphenyl)-2,3-phthalazin-1-one(DHPZ),which is a twisted non-coplanar heterocyclic bisphenol-like monomer.The newly generated polymer was evaluated based on characterization of its solubility,viscosity measurements,elemental analysis,FTIR spectroscopy,differential scanning calorimetric and thermogravimetric studies. 相似文献
877.
Aimin Hao Xiaocui Yang Chunxiao Gao Yonghao Han Yongjun Tian 《Journal of Physics and Chemistry of Solids》2009,70(2):433-438
A theoretical investigation on the structural stabilities and electronic properties of HgTe under high pressure was conducted using first principles based on density functional theory. Our results demonstrate that the sequence of the pressure-induced phase transitions of HgTe is from the zinc blende, to cinnabar, rocksalt, orthorhombic, and CsCl-type structures. The pressure effects on the optical properties were discussed and compared with previous calculations and experimental data whenever available. 相似文献
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Inside Back Cover: Weak Ligand‐Field Effect from Ancillary Ligands on Enhancing Single‐Ion Magnet Performance (Chem. Eur. J. 36/2016) 下载免费PDF全文
880.