反对称简易十二极场磁铁的设计

在散裂靶或废束站上形成均匀的、形状规则化的束斑分布,是散裂中子源、加速器驱动次临界系统(ADS)等高功率强流质子束应用研究课题中共性的关键技术.目前国际上一般认为采用反对称非线性高阶场磁铁进行打靶束斑均匀化变换是较为合适的.提出了一种新颖的非线性场磁铁——反对称垂直双向聚焦简易十二极场磁铁,该磁铁可以在交叉垂直的两个方向同时聚焦束晕粒子至束核内层或束团中心区域,可以较好地控制束晕;并配合其他反对称高阶场磁铁或阶梯场磁铁,可以在靶上较容易地得到基本均匀分布的近似圆斑束.同时给出了该种磁铁的结构装置及其制造方法.

郭店簡《魯穆公》篇“恆稱”新證

郭店楚簡《魯穆公問子思》篇"恆稱"說屢見。本文支持"恆"、"亙"讀爲"亟(極)"的意見,認爲"極(亟)稱"實即"極言","極言"就是"直言規勸"。"極言",爲什麽能訓爲"直言"呢?《呂氏春秋·先識》"極言"高誘注說得很清楚:"極,盡。"可見"極言"就是"盡言",就是規勸諫,毫無保留。《穀梁傳·文公十三年》的"極稱"說亦同。由此看,馬王堆帛書《繫辭》篇的"大恆"讀爲"太極",也是可以成立的。

解矩阵方程sum (A_1X_1B_1=C) from l=1 to N反对称解的一个迭代算法

对于求解线性矩阵方程sum (A_1X_1B_1=C) from l=1 to N的反对称解X_1,X_2,...,X_N的问题,文章给出一个迭代算法,用这个算法可判断方程是否存在反对称解。若如果矩阵方程相容,就可以通过有限步的迭代之后得到反对称解;若选择特定的初始值,则通过迭代之后得到的是它的极小范数反对称解。

矩阵方程AXB=C的反对称解和极小范数反对称解

建立了求矩阵方程AXB=C反对称解的迭代方法.使用该方法不仅能够判断反对称解的存在性,而且在有反对称解时,能够在有限步迭代计算之后得到反对称解.选取特殊的初始矩阵,可求得极小范数反对称解.

A 2.4GHz CMOS Quadrature Voltage-Controlled Oscillator Based on Symmetrical Spiral Inductors and Differential Diodes

A voltage controlled oscillator (VCO) which can generate 2 4GHz quadrature local oscillating (LO) signals is reported.It combines a LC VCO,realized by on chip symmetrical spiral inductors and differential diodes,and a two stage ring VCO.The principle of this VCO is demonstrated and further the phase noise is discussed in detail.The fabrication of prototype is demonstrated using 0 25μm single poly five metal N well salicide CMOS digital process.The reports show that the novel VCO is can generate quadrature LO signals with a tuning range of more than 300MHz as well as the phase noise--104 33dBc/Hz at 600KHz offset at 2 41GHz (when measuring only one port of differential outputs).In addition,this VCO can work in low power supply voltage and dissipate low power,thus it can be used in many integrated transceivers.

Ni doped La_(0.6)Sr_(0.4)FeO_(3-δ) symmetrical electrode for solid oxide fuel cells

The conventional Ni cermet anode suffers from severe carbon deposition and sulfur poisoning when fossil fuels are used. Alternative anode materials are desired for high performance hydrocarbon fuel solid oxide fuel cells （SOFCs）. We report the rational design of a very active Ni doped La0.6Sr0.4FeO3‐δ（LSFN） electrode for hydrocarbon fuel SOFCs. Homogeneously dispersed Ni‐Fe alloy nanoparticles were in situ extruded onto the surface of the LSFN particles during the operation of the cell. Sym‐metric SOFC single cells were prepared by impregnating a LSFN precursor solution onto a YSZ （yt‐tria stabilized zirconia） monolithic cell with a subsequent heat treatment. The open circuit voltage of the LSFN symmetric cell reached 1.18 and 1.0 V in humidified C3H8 and CH4 at 750？？, respective‐ly. The peak power densities of the cells were 400 and 230 mW/cm2 in humidified C3H8 and CH4, respectively. The electrode showed good stability in long term testing, which revealed LSFN has good catalytic activity for hydrocarbon fuel oxidation.

Kinetic Implication from Temperature Effect on Hydrogen Evolution Reaction at Ag Electrode

Hydrogen evolution reaction （HER） at polycrystalline silver electrode in 0.1 mol/L HClO4 solution is investigated by cyclic voltammetry in the temperature range of 278-333 K. We found that at electrode potential φa,app decreases with φ, while pre-exponential factor A remains nearly unchanged,which conforms well the prediction from Butler-Volmer equation. In contrast, with φ nega-tive shifts from the onset potential for HER to the potential of zero charge （PZC≈-0.4 V）, both Ea,app and A for HER increase （e.g., Ea,app increases from 24 kJ/mol to 32 kJ/mol）. The increase in Ea,app and A with negative shift in φ from -0.25 V to PZC is explained by the increases of both internal energy change and entropy change from reactants to the transition states, which is correlated with the change in the hydrogen bond network during HER. The positive entropy effects overcompensate the adverse effect from the increase in the activation energy, which leads to a net increase in HER current with the activation energy negative shift from the onset potential of HER to PZC. It is pointed out that entropy change may contribute greatly to the kinetics for electrode reaction which involves the transfer of electron and proton, such as HER.

Temperature Effect on Hydrogen Evolution Reaction at Au Electrode

The temperature dependence of hydrogen evolution reaction （HER） at a quasi-single crystalline gold electrode in both 0.1 mol/L HCl04 and 0.1 mol/L KOH solutions was investigated by cyclic voltammetry. HER current displays a clear increase with reaction overpotential （η） and temperature from 278-333 K. In 0.1 mol/L HClO4 the Tafel slopes are found to increases slightly with temperature from 118 mV/dec to 146 mV/dec, while in 0.1 mol/L KOH it is ca. 153±15 mV/dec without clear temperature-dependent trend. The apparent activation energy （Ea） for HER at equilibrium potential is ca. 48 and 34 kJ/mol in 0.1 mol/L HC104 and 0.1 mol/L KOH, respectively. In acid solution, Ea decreases with increase in η, from Ea-37 kJ/mol （η=0.2 V） to 30 kJ/mol （η=0.35 V）. In contrast, in 0.1 mol/L KOH, Ea does not show obvious change with U. The pre-exponential factor （A） in 0.1 mol/L HC104 is ca. 1 order higher than that in 0.1 mol/L KOH. Toward more negative potential, in 0.1 mol/L HC104 A changes little with potential, while in 0.1 mol/L KOH it displays a monotonic increase with U. The change trends of the potential-dependent kinetic parameters for HER at Au electrode in 0.1 mol/L HClO4 and that in 0.1 mol/L KOH are discussed.

Exclusive Semileptonic Rare Decays B→K()(?)+(?)^- in a Top Quark Two-Higgs-Doublet Model

Employing improved calculations of the decay form factors from light-cone sum rules, we evaluate the invariant mass spectrum, forward-backward asymmetry, and lepton polarizations of the exclusive processes B → K^（＊）e＋e- in the SM and T2HDM. From the recent measurements of their branching ratios, we find that these processes do provide additional bounds on the new parameters in the model considered here. After the inclusion of the new physics contributions, the large enhancement of FBA, which is unobservably small within the SM and of the lepton polarization at large tan β, may precisely test the SM or reveal new physics in forthcoming accurate experiments.

测量在控制注浆减沉中的应用方法探讨

文中提出了测量控制下注浆减沉方法,优化了传统的注浆减沉方法,提高了减沉效果和煤炭采出率,节约了注浆成本,为指导“三下”开采实践和解决“三区”(煤采区、基岩区、地表下沉区)问题提供了依据。

Distinct patterns of monthly Southern Annular Mode events

The Southern Annular Mode(SAM)is the leading mode of atmospheric variability in the mid–high latitudes of the Southern Hemisphere,representing large-scale variations in pressure and the polar front jet(PFJ).In SAM events,the combination of the SAM and other modes may result in different atmospheric patterns.In this study,a neural-network-based cluster technique,the self-organizing map,was applied to extract the distinct patterns of SAM events on the monthly time scale based on geopotential height anomalies at 500 hPa.Four pairs of distinguishable patterns of positive and negative SAM events were identified,representing the diversity in spatial distribution,especially the zonal symmetry of the center of action at high latitudes—that is,symmetric patterns,split-center patterns,West Antarctica patterns,and a tripole pattern.Although the SAM is well known to be beltshaped,within the selected SAM events,the occurrence frequency of symmetric patterns is only 23.8%—less than that of West Antarctica patterns.Diverse PFJ variations were found in the symmetric and asymmetric patterns of SAM events.The more asymmetric the spatial distribution of the pressure anomaly,the more localized the adjusted zonal wind anomaly.The adjusted PFJ varied in meridional displacement and strength in different patterns of SAM events.In addition,the entrance and exit of the jet changed in most of the patterns,especially in the asymmetric patterns,which might result in different climate impacts of the SAM.

Deexcitation Energy of Superdeformed Secondary Minima as a Probe to Density Dependence of Symmetry Energy

Deexcitation energies of superdeformed secondary minima of odd-odd A u and T1 isotopes are investigated with the relativistic mean field （RMF） model where the isoscalar-isovector coupling is included to change the symmetry energy. It is verified by the theoretical analysis and numerical results that the deexcitation energies of superdeformed secondary minima relative to the ground states in these heavy nuclei are sensitive to differences in the symmetry energy. In particular, the linear correlation between the deexeitation energies of odd-odd Au and T1 isotopes and the neutron skin thickness in 208Pb is established. Moreover, explorations are extended to superdeformed candidates of other mass regions. It is found that the linear correlation can even be established between the deexcitation energies and the symmetry pressure at subsaturation density. These indicate that deexcitation energies can serve as a probe to the density dependence of the symmetry energy.

The Minimal Submanifolds in a Locally Symmetric and Conformally Flat Riemannian Manifold

In this paper,we extend two important theorem in[1],[2]to the minimal submanifolds in a Locally symmetric and conformally flat Riemannian mainfold N^(+p).When N^(+p)is a space S_(1)^(+p) of constant curvature,our theorems reduce to the theorems of[1],[2].

论正常之恶:郭店竹书《鲁穆公问子思》的哲学分析

郭店竹书《鲁穆公问子思》之“极称”应为以远远超出正常状态的极限性批判方式对君主进行谏诤。在大儒子思看来,忠臣就应该“极称其君之恶”。鲁穆公对子思的忠臣观“不悦”,并“揖而退之”的做法本身就是“君之恶”。这就形成了一种认知矛盾和逻辑矛盾--恶不自认为恶,普遍认知和个人认知存在矛盾。不以恶为恶的原因在于,心理定势的日积月累所造成的“正常”构成了对“恶”的辩护,并由此形成“正常之恶”。

Elliptic systems involving multiple critical nonlinearities and symmetric multi-polar potentials

In this paper,a system of elliptic equations is investigated,which involves multiple critical Sobolev exponents and symmetric multi-polar potentials.By variational methods and analytic techniques,the relevant best constants are studied and the existence of(Zk×SO(N.2))2-invariant solutions to the system is established.

The Properties of Bianalytic Functions with Zero Arc at a Pole

In this paper, the properties of bianalytic functions w（z） = z^-Ф1（z） ＋Ф2（z） with zero arc at the pole z = 0 are discussed. Some conditions under which there exists an arc γ, an end of which is z = 0, such that w（z） =0 for arbitary z ∈γ／{0} are given. Secondly, that the limit set of w（z） is a circle or line as z → 0 is proved in this case. Finally, two numerical examples are given to illustrate our results.

One-step electrodeposition fabrication of Ni_3S_2 nanosheet arrays on Ni foam as an advanced electrode for asymmetric supercapacitors

Ni3S2 nanosheet(NS) arrays on Ni foam were fabricated by a simple one-step electrodeposition strategy, and used as a kind of electrode material for asymmetric supercapacitors. The Ni3S2 NS arrays are interconnected, which can be regarded as bridges between these individual nanoparticle units. The electrochemical performances were evaluated by cyclic voltammetry and chronopotentiometry techniques in a three-electrode system. The Ni3S2 NS arrays display a specific capacitance of 773.6 F g^-1 at 1 A g^-1, and excellent rate property of 84.3% at 10 A g^-1. The performance of the Ni3S2 NS arrays was further investigated in an asymmetric supercapacitor for potential practical application. The asymmetric supercapacitor using the Ni3S2 electrode and reduced graphene oxide electrode as positive and negative electrodes, respectively, exhibits an energy density of 41.2 W h kg^-1 at 1.6 kW kg^-1. When up to 16 kW kg^-1, it holds 25.3 W h kg^-1.These excellent electrochemical performances are attributed to the improved electronic conductivity and rich redox reaction sites from Ni3S2 NS arrays. Our results indicate that the Ni3S2 NS arrays have great potential for supercapacitors.

Design of GaAs/Al_xGa_(1-x)As asymmetric quantum wells for THz-wave by difference frequency generation

The energy levels, wave functions and the second-order nonlinear susceptibilities are calculated in GaAs/Al0.2Ga0.8As/Al0.5Ga0.5As asymmetric quantum well （AQW） by using an asymmetric model based on the parabolic and non-parabolic band. The influence of non-parabolicity can not be neglected when analyzing the phenomena in narrow quantum wells and in higher lying subband edges in wider wells. The numerical results show that under double resonance （DR） conditions, the second- order difference frequency generation （DFG） and optical rectification （OR） generation susceptibilities in the AQW reach 2.5019 μm/V and 13.208 μm/V, respectively, which are much larger than those of the bulk GaAs. Besides, we calculate the absorption coefficient of AQW and find out the two pump wavelengths correspond to the maximum absorption, so appropriate pump beams must be selected to generate terahertz （THz） radiation by DFG.

THE SPACE-FRACTIONAL TELEGRAPH EQUATION AND THE RELATED FRACTIONAL TELEGRAPH PROCESS

The space-fractional telegraph equation is analyzed and the Fourier transform of its funda-mental solution is obtained and discussed.A symmetric process with discontinuous trajectories, whose transition function satisfies thespace-fractional telegraph equation, is presented. Its limiting behaviour and the connectionwith symmetric stable processes is also examined.

A study on surface symmetry and interfacial enhancement of SrTiO_3 by second harmonic generation

The symmetry of the surfaces of SrTiO3 and slightly Nb-doped SrTiO3 crystals was investigated by the optical reflected second harmonic generation technique. The good agreement between experimental and theoretical results of the second harmonic in- tensity dependence on the azimuth angle indicates that the SrTiO3 （001） surface is with 4ram symmetry and the Nb-doped SrTiO3 （111） surface with 3m symmetry. The measurements of the polarization dependent second harmonic intensity confirm that conclusion. The enhancement of the surface polarization in the structure of SrTiO3 capped La0.9Sr0.1MnO3 films compared with that in the La0.9Sr0.1MnO3 films has been obtained.