双(1,3-二硫杂环戊烯-2-硒酮-4,5-二硫)金属配合物的合成及其电化学性质的研究

以1，3-二硫杂环戊烯-2-硒酮-4，5-二硫盐为配体与二价金属离子配位合成了4种双(1，3-二硫杂环戊烯-2-硒酮-4，5-二硫)金属配合物，研究了它们的电化学性质和UV—Vis光谱，并讨论了形成中性产物的原因。     

Oscillatory and Asymptotic Behavior for Second Order Quasilinear Difference Equations

1 IntroductionConsider the second order quasilinear difference equationA(g(Ay.--l)) + f(n,y.) = 0, for n E N(no), (l'l)where A is defined by Ay. = Vn+1--yn, n E N(no) = {no, no + 1,'' }, nO E N = {l, 2,'. }.The following hold throughout the paPer:(H0) (i) g: R-R is a continuous increasing fUnction with propertiessgng(y) = sgny) g(R) = R;(il) f: N(no) x R--+ R is continuous as a function of y E R;(iii) yf(n,y) > 0 for n E N and y / 0.By a solution of the equation (1.l) we mean a non…     

提升小波的X射线脉冲星信号降噪EI北大核心CSCD

对于短时间内X射线脉冲星信号形成的脉冲轮廓的信噪比低,提出基于提升小波的X射线脉冲星信号的降噪方法。分析了基于提升小波的信号降噪理论模型。在周期叠加的基础上,利用探测设备及空间环境的先验信息建立预降噪模型,并对X射线脉冲星的脉冲轮廓做降噪预处理。通过选择小波和自适应的阈值函数,利用提升小波对脉冲轮廓降噪。通过对多组罗西X射线计时探测器(RXTE)卫星探测的实测X射线脉冲星数据的仿真分析,结果表明,降噪后的脉冲轮廓信噪比得到提高,且算法有更快的处理速度。     

带p-Laplacian算子三点奇异边值问题多个对称正解的存在性

利用凸锥上的不动点定理,研究了一类带p-Laplacian算子的微分方程三点奇异边值问题对称正解的多重性,得到了这类边值问题存在多个对称正解的充分条件.     

中立型时滞微分方程的渐近稳定性

考虑具有正负系数的中立型时滞微分方程ｄｄ狋［狓（狋）－犘（狋）狓（狋－τ）］＋犙（狋）狓（狋－δ）－犚（狋）狓（狋－σ）＝０，　狋≥狋０， 其中Ｐ（ｔ）∈Ｃ（［ｔ０，∞），Ｒ），Ｑ（ｔ），Ｒ（ｔ）∈Ｃ（［ｔ０，∞），Ｒ＋ ），τ，δ，σ∈（０，∞）．获得了该方程零解 一致稳定及渐近稳定的充分条件，它推广并改进了现有文献中的结论．     

Error and jitter effect studies on the SLED for the BEPC Ⅱ-linac

An RF pulse compressor is a device used to convert a long RF pulse to a short one with a much higher peak RF magnitude. SLED can be regarded as the earliest RF pulse compressor to be used in large-scale linear accelerators. It has been widely studied around the world and applied in the BEPC and BEPC linac for many years. During routine operation, error and jitter effects will deteriorate the performance of SLED, either on the output electromagnetic wave amplitude or phase. The error effects mainly include the frequency drift induced by cooling water temperature variation and the frequency/Q 0 /β unbalances between the two energy storage cavities caused by mechanical fabrication or microwave tuning. The jitter effects refer to the PSK switching phase and time jitters. In this paper, we re-derive the generalized formulae for the conventional SLED used in the BEPC linac, and the error and jitter effects on SLED performance are also investigated.     

Error and jitter e ect studies on the SLED for the BEPCⅡ-linac

An RF pulse compressor is a device used to convert a long RF pulse to a short one with a much higher peak RF magnitude. SLED can be regarded as the earliest RF pulse compressor to be used in large-scale linear accelerators. It has been widely studied around the world and applied in the BEPC and BEPCⅡ linac for many years. During routine operation, error and jitter effects will deteriorate the performance of SLED, either on the output electromagnetic wave amplitude or phase. The error effects mainly include the frequency drift induced by cooling water temperature variation and the frequency/Q₀/β unbalances between the two energy storage cavities caused by mechanical fabrication or microwave tuning. The jitter effects refer to the PSK switching phase and time jitters. In this paper, we re-derive the generalized formulae for the conventional SLED used in the BEPCⅡ linac, and the error and jitter effects on SLED performance are also investigated.     

苯的碘代反应能进行吗

高中化学课本（乙种本）下册,（甲种本）第三册,在讲解有机化合物苯与卤素的取代反应时,列举了苯与Br2亲电取代反应的例子,并且写道：“用铁屑作催化剂,苯也能跟其他卤素起取代反应”。言外之意,就是说苯也能跟Br2以外的F2、Cl2、I2发生取代反应。那么,上述取代反应都能进行吗?     

带p-Laplacian算子多点边值问题对称正解的多重性

本文应用凸锥上的Avery-Peterson不动点定理,讨论了一类带p-Laplacian算子多点边值问题对称正解的多重性,得到了这类边值问题至少存在三个对称正解的充分条件,并给出了一个具体的例子阐释这一结果的重要性.     

由一道高数证明题所想

针对关于二重积分与定积分的一道积分换元证明题,从二次积分法,原函数法．二重积分换元法的不同角度给出证明．通过对几种不同解题思路的探究．激发学生的兴趣．启迪学生的思维．