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71.
马堃  颉录有  张登红  董晨钟  屈一至 《物理学报》2016,65(8):83201-083201
本文利用密度矩阵理论和Racah代数推导出了光电子角分布的一般计算公式, 并在多组态Dirac-Fock方法基础上发展了计算原子光电离过程中产生的光电子角分布的相对论程序, 利用该程序对氖原子2s和2p光电子角分布的偶极和非偶极参数进行了具体计算, 所得结果与已有文献具有很好的一致性. 在此基础上, 本文讨论了光子与电子相互作用多级展开中的非偶极项以及入射光的极化性质对光电子角分布的影响.  相似文献   
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The 2-D nanostructure, due to unprecedented physical, electronic, and chemical properties, was widely dedicated to the zooms of electrocatalysis, batteries, supercapacitors, solar cells, photocatalysis and sensing platforms. Herein, we reported a sort of low-applied potential non-enzymatic glucose sensor, which used ultrathin 2-D CuS nanowall arrays (CuS-NWAs) fabricated directly onto fluorine-doped tin oxide glass by potentiostatically deposition approach. Meaningfully, the potentiostatical-deposition time can control precisely the frame of 2-D CuS-NWAs on size and thickness and assist to ferret out the growing mechanization by analyzing the copper valence. Then, CuS-NWAs-based non-enzymatic glucose sensor presented the high sensitivity (2610 μA mM−1 cm−2), a low detection of 17 nM, fast respond time (1.5–6.2 s) and low detection limits (2.6–17.7 nM, S/N=3) regardless of an applied potential as low as 0.33 V (vs. Ag/AgCl), attributed to that the 2-D CuS-NWAs offer large active area with numerous exposed active points, a low-resistance electron-shuttling passage and door-opened glucose-diffusion channel. Additionally, it was found that the sensitivity of CuS-NWAs-based non-enzymatic glucose sensors can be optimized by altering electrodeposition duration for CuS-NWAs growth. Confirmedly, the 2-D CuS-NWAs can be promised as a new system for high-performance electrochemical sensors with excellent properties of selectivity, stability and reproducibility.  相似文献   
74.
The number of ψ’ events accumulated by the BESⅢ experiment from March 3 through April 14, 2009, is determined by counting inclusive hadronic events. The result is 106.41×(1.00±0.81%)×106 . The error is systematic dominant; the statistical error is negligible.  相似文献   
75.
考虑带常延迟的延迟积分微分方程线性系统零解的渐近稳定性,本文采用拉格朗日插值的线性多步方法,探讨了系统数值方法的线性稳定性。证明了所有A-稳定且强零-稳定的Pouzet型线性多步方法能够保持原线性系统的延迟不依赖稳定性。  相似文献   
76.
The paper reports the three-phase (gas + aqueous liquid + hydrate) equilibrium pressure (p) versus temperature (T) data for a (O3 + O2 + CO2 + H2O) system and, for comparison, corresponding data for a (O2 + CO2 + H2O) system for the first time. These data cover the temperature range from (272 to 279) K, corresponding to pressures up to 4 MPa, for each of the three different (O3 + O2)-to-CO2 or O2-to-CO2 mole ratios in the gas phase, which are approximately 1:9, 2:8, and 3:7, respectively. The mole fraction of ozone in the gas phase of the (O3 + O2 + CO2 + H2O) system was from ∼0.004 to ∼0.02. The modified pressure-search method, developed in our previous study [S. Muromachi, T. Nakajima, R. Ohmura, Y.H. Mori, Fluid Phase Equilib. 305 (2011) 145–151] for pT measurements in the presence of chemically unstable ozone, was applied, having been further modified for dealing with highly water-soluble CO2, for the (O3 + O2 + CO2 + H2O) system, while the conventional temperature-search method was used for the (O2 + CO2 + H2O) system. The measurement uncertainties (with 95% coverage) were ±0.11 K for T, ±6.0 kPa for p, and ±0.0015 for the mole fraction of each species in the gas phase. It was confirmed that, at a given CO2 fraction in the gas phase, p for the (O3 + O2 + CO2 + H2O) system was consistently lower than that for the (O2 + CO2 + H2O) system over the entire T range of the present measurements, indicating a preference of O3 to O2 in the uptake of guest-gas molecules into the cages of a structure I hydrate.  相似文献   
77.
“常乐”稀土微肥对糯玉米冠层光合特性及产量的影响   总被引:1,自引:0,他引:1  
在50,100,200,400,600,800 mg.kg-1浓度的"常乐"稀土微肥条件下,研究了其对糯玉米冠层叶的叶绿素含量、荧光参数及产量构成因素的影响。结果表明,糯玉米授粉后棒三叶的叶绿素含量及荧光参数的增大幅度明显随常乐处理剂量的增大而呈规律性变化:即T1至T4处理不仅叶绿素含量呈现明显增大趋势,而当处理浓度为600 mg.L-1时叶绿素含量则表现下降,而且PSII的潜在活性(FV/F0)、光化学最大效率(FV/Fm)和量子效率(ΦPSII)亦表现出相似的规律;但PSII的光化学猝灭系数(qP)则随常乐处理浓度的增大,表现出先增后减的规律,优势明显并具有较高的光合速率,尤其是400 mg.kg-1光合功能强,籽粒产量最高达16320.0 kg.hm-2。另外,授粉后的生育期也对鲜食糯玉米冠层叶绿素荧光参数具有明显正效应,在授粉后16 d时,不同浓度"常乐"稀土微肥处理的鲜食糯玉米不同叶位叶光合速率最大。  相似文献   
78.
考虑Simon反谱理论新方法中引入的A-函数,根据Weyl函数m关于A-函数的表示关系,利用广义函数和Fourier变换的方法求出A-函数关于Weyl函数m的反表示,该结论表明A-函数的本质是广义函数.  相似文献   
79.
In this paper, strontium carbonate (SrCO3) and barium carbonate (BaCO3) crystals were synthesized in the presence of an organic additive-hexamethylenetetramine (HMT) using two CO2 sources. Scanning electron microscopy and X-ray powder diffractometry were used to characterize the products. The results showed that the morphologies of orthorhombic strontianite SrCO3 transformed from branch-like to flower-like, and to capsicum-like at last, while the morphologies of BaCO3 change from fiber-like to branchlike, and to rod-like finally with an increase of the molar ratio HMT/Sr2+ and HMT/Ba2+ from 0.2 to 10 using ammonium carbonate as CO2 source. When using diethyl carbonate instead of ammonium carbonate as CO2 source, SrCO3 flowers aggregated by rods and BaCO3 shuttles were formed. The possible formation mechanisms of SrCO3 and BaCO3 crystals obtained in different conditions were also discussed.  相似文献   
80.
以2-甲基-8羟基喹啉作为起始原料,两步反应合成有机双齿配体HL,并通过核磁、质谱和元素分析表征其结构;配体HL与Co(NO3)2反应生成单核配合物1,该配合物属单斜晶系,P2/c空间群,晶胞参数为a=10.967(7),b=8.639(5),c=18.087(11);V=1 656.0(17)3,Z=4,Dc=1.541 mg/m3,最终R1=0.032 0,wR2=0.078 4。该配合物中钴原子是五配位,它们分别和两个配体中包含的N2O24个原子及一个吡啶N原子配位形成扭曲的三角双锥构型,X-射线粉末衍射表明其具有单一的纯相,热重分析表明其基本骨架具有较好的热稳定性。  相似文献   
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