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991.
Quantum systems that are confined to circuit geometries are called quantum circuits. Macroscopic superconducting circuits
are quantum circuits which can be modelled using a Quantisation by Parts scheme based on the macroscopic wave function approach of Feynman. This paper studies the circuit composed of an input wire
and an output plate. We find that in order to achieve a consistent theory of supercurrent flow we have to generalize the quantisation
by parts scheme to quantise in a path space. The generalized theory predicts a current flow down the wire into the plane.
In addition to a current flowing radially outwards in the plane, the theory allows a circulating current round the origin.
Strikingly, the circulating current can flow clockwise or anti-clockwise in such a way as to generate a magnetic moment of
magnitude half of a Bohr magneton for an orbiting electron in an atom and a magnetic flux half that of the magnetic flux quantum
of a superconducting ring. There is also the possibility of a macroscopic superposition of the two states of opposing circulating
currents resembling a Schr?dinger’s cat situation. Furthermore, we outline a setup involving an external magnetic field that
may allow experimental tests of the theory. 相似文献
992.
The solid neon matrix isolated spectrum of CO2 are recorded in the 2–5 μm region. Natural and 13C or 18O enriched CO2 samples were used and the nν1 + ν3 (n = 0, 1, 2) series bands of different CO2 isotopologues have been observed. The solid neon matrix shift due to Fermi-resonance of bands within the same vibrational polyad is analyzed. 相似文献
993.
994.
Fu-Ming Wang Chien-Chieh Hu Shen-Chuan Lo Yung-Yun Wang Chi-Chao Wan 《Solid State Ionics》2009,180(4-5):405-411
The effect of EO side chain functionalization on the transport and electrochemical properties of polysiloxane electrolytes has been examined in this report. First, a study of the electrochemical stability of the electrolytes by linear sweep voltammetry shows that the polymer electrolytes have a negligible effect on the electrolyte stability windows. In addition, the parameters of cation mobility in polysiloxane electrolytes, such as ionic transference numbers and diffusion coefficients, were increased by increasing the lengths of the EO side chain. However, cation mobility in polymer structures is quite different compared to liquid-based systems and is probably suppressed, resulting in their polymer structure. Therefore, Positron Annihilation Lifetime Spectroscopy (PALS) was used to study the relationship between orthopositronium (o-Ps) lifetime, free volume radius, free volume of micro voids and EO side chain affection at different temperatures. Finally, a battery application with LiCoO2 and LiFePO4/polymer electrolyte/lithium metal electrode was monitored for its potential use in the future. 相似文献
995.
悬浮液进样流动注射在线微波消解-冷蒸气原子荧光光谱法测定生物和环境样品中的汞 总被引:12,自引:0,他引:12
建立了悬浮液进样流动注射在线微波消解-冷蒸气原子荧光光谱法测定生物和环境样品中Hg的方法。样品分散在50%(V/V)王水中,通过磁力搅拌保证样品溶液的均一性与稳定性。方法的检出限为O.06μ/L。方法简单快速,灵敏度高,样品损失少,而且没有样品交叉污染。应用此方法测定了5种标准参考物质以及5个实际样品中的Hg含量,并与传统的高压焖罐强酸消解方法进行了比较,两种方法所得结果一致,标准参考物质的测定值与标准值很好地吻合。 相似文献
996.
Tb3+∶YAG单晶荧光层中掺杂Ga3+的荧光敏化作用 总被引:1,自引:0,他引:1
采用液相外延工艺成功制备了Tb3 + ∶YAGG单晶荧光层 ,研究了Tb3 + 激活YAG主晶格外延层中Ga3 + 掺杂的荧光敏化效应 ,可以看到在Tb3 + 荧光得到显著增强的同时 ,外延荧光层发光的饱和特性也有所改善。实验中观察到了Ga3 + 掺杂后基质晶体吸收边缘向长波方向展宽 ,并与Tb3 + 的7F6 9E、7E典型吸收峰发生交叠的现象 ,用基质与Tb3 + 之间的声子耦合解释了上述Tb3 + ∶YAGG外延层中所存在的能量传递、荧光敏化现象。基质与掺杂激活中心间能量传递机制的建立将会为基于YAG主晶格的高效荧光材料研究提供一个新的思路。 相似文献
997.
SUN Ya-Guang RONG Shu-Ting WU Yong-Li YU Wan WANG Chuan-Sheng ZHANO Wan-Zhong GAO En-Jun 《结构化学》2009,28(9)
The 1-D chain coordination complex of {[Mn2(HCAM)3(H2bipy)]·5H2O}n(H3CAM=4-hydroxypyridine-2,6-dicarboxylic acid,bipy=4,4′-bipyridine) has been synthesized by the reaction of 4-hydroxypyridine-2,6-dicarboxylic acid,4,4′-bipyridine and manganese carbonate under hydrothermal conditions,and its crystal structure was determined by X-ray diffraction method.The crystal belongs to the monoclinic system,space group P21/n with a=10.110(2),b=20.159(4),c=17.861(4) ,β=99.67(3)°,V=3.5884(12) nm3,Mr=901.47,Z=4,Dc=1.669 g·cm-3,μ=0.798 mm-1,F(000)=1840,the final R=0.0713 and wR=0.1853.The complex forms a 1-D chain bridged by HCAM,protonated 4,4-bipyridines link the 1-D chains to construct 2-D networks via N-H…O hydrogen bonds,and networks are further extended via π-π stacking and hydrogen bonds into 3-D supramolecular framework. 相似文献
998.
A rapid and simple as well as sensitive inductively coupled plasma mass spectrometry (ICP-MS) method for the determination
of cobalamin is described. Cobalamin in human urine and medicine tablet solutions was converted on-line into free cobalt ions
in acid medium, the cobalt ions were then detected by ICP-MS. Cobalamin was determined by measuring the increase of integral
counts per second intensity, which was linear over the cobalamin concentration range of 1.0 × 10−10 g mL−1 to 8.0 × 10−5 g mL−1, and the limit of detection was 0.05 ng mL−1 (3σ). At the pump rate of 30 rotations per minute, one analysis cycle of cobalamin, including sampling and washing, could be
accomplished in 0.5 min with the relative standard deviations of less than 5 %. The proposed procedure was applied successfully
in monitoring cobalamin in human urine without any pretreatment process and in rapid determination of cobalamin in multivitamin
tablets. 相似文献
999.
Pyridotriazol-1-yloxypyrimidine 3 reacts with arylboronic acids under palladium-free, Cs2CO3, (0.8%) H2O2, and DME conditions to produce heteroaryl ethers 4-16 in good yields comparable to the oxidative palladium-catalyzed reaction. The yields of aryl ethers 17-19 from quinazoline 2 with (0.8%) H2O2 were modest. Hydrogen peroxide is superior to dioxygen as an oxidant in these reactions. 相似文献
1000.
Penguins live in the extremely cold Antarctic. Understanding the thermal radiative properties of penguin down may help us to develop super insulating materials. In this study, Fourier transform infrared spectroscopy (FTIR) was applied to measure the thermal radiative properties of penguin down and compare them with those of other fibrous materials. It was found that penguin and duck down are superior to other fibrous materials, such as polyester, Thinsulate and wool, at the same fibre volume fraction, in shielding the radiative heat transmission, largely due to their fine fibre diameter. There is an optimum fibre diameter at which the fibrous materials are at their best in blocking thermal radiation. The fibre diameter of penguin down is very close to this optimum value. The study further found that the relationship between the effective thermal radiative conductivity and fibre fineness may be better fitted with a quadratic curve. 相似文献