长江三角洲国际性城市群发展战略研究

国际性城市群的建设是我国城市在下世纪参与国际竞争的重要战略 ,以沪宁杭为中心的长江三 角洲城市群是我国参与 21世纪全球城市间国际竞争进而发展成为国际性城市群的主要代表 ,既分工明 确 ,又联合协作 ,是长江三角洲地区各主要中心城市实现国际性城市群战略的基本保证.     

On Rearrangements of the Haar System in L p

In this paper we study operators rearranging the Haar system in each bundle. It is proved that the norm of any nonidentical rearrangement admits a nontrivial lower bound in L ^p spaces, .     

The best possibility of the grand Furuta inequality

Let be invertible bounded linear operators on a Hilbert space satisfying , and let be real numbers satisfying Furuta showed that if , then . This inequality is called the grand Furuta inequality, which interpolates the Furuta inequality
and the Ando-Hiai inequality ( ).

In this paper, we show the grand Furuta inequality is best possible in the following sense: that is, if , then there exist invertible matrices with which do not satisfy .

     

Higher order symmetric spaces and the roots of the identity in a Lie group

Let denote the set of all -roots of the identity in a Lie group . We show that is always an embedded submanifold of , having the conjugacy classes of its elements as open submanifolds. These conjugacy classes are examples of -symmetric spaces and we show, more generally, that every -symmetric space of a Lie group is a covering manifold of an embedded submanifold of . We compute also the Hessian of the inclusions of and into , relative to the natural connection on the domain and to the symmetric connection on .

     

The Furuta inequality in Banach -algebras

Let be real numbers with and Furuta (1987) proved that if bounded linear operators on a Hilbert space satisfy , then . This inequality is called the Furuta inequality and has many applications. In this paper, we prove that the Furuta inequality holds in a unital hermitian Banach -algebra with continuous involution.

     

The Order of Best Approximation in Some Classes of Functions

Starting from the equivalence between the Ditzian–Totik modulus and , where , in this article large classes of functions are introduced for which the modulus can be easily calculated. As a consequence, very good estimates for the bestapproximation are obtained. The attempts to estimate or calculate themodulus can be a very intricateproblem.     

负值量子条件熵与双量子系统一类混合态纠缠量度

运用负值量子条件熵研究了双量子系统一类混合态的纠缠量度.给出了负值量子条件作为条件熵纠缠度的定义，证明了条件熵纠缠满足作为2×2系统一类混合纠缠态量度的四个基本条件.当双量子系统处于纯态时，条件熵纠缠度即为部分熵纠缠度.应用条件熵纠缠度研究了真空腔场中两全同二能级原子之间纯态和一类混合态纠缠的时间演化，比较了相同条件下两全同原子系统concurrence纠缠度的时间演化.结果表明，两纠缠度演化规律完全一致，验证了负值量子条件熵可以作为双量子系统纯态和一类混合态的纠缠量度. 关键词： 双量子系统 负值量子条件熵 条件熵纠缠度 混合态纠缠度     

高电荷态离子40Arq+与Si表面作用中的电子发射产额

报道了在兰州重离子加速器国家实验室电子回旋共振离子源原子物理实验平台上，用高电荷态⁴⁰Ar^q+(1≤q≤12)离子作用于半导体Si固体表面时的电子发射产额实验测量.实验中，通过改变炮弹离子的电荷态和引出电压选取其不同的势能和动能，系统地研究了入射离子势能沉积和与其在固体中的电子能损对表面电子发射产额的贡献.结果表明，作为引起表面电子发射的两个主要因素，单离子的电子发射产额与炮弹离子在固体表面的势能沉积和电子能损都有近似的正比关系.     

中国优秀物理学家的杰出代表——葛庭燧

回顾介绍了葛庭燧院士的生平和他在科学研究、人才培养方面所作出的贡献,展示了他的高尚情操,分析了他取得卓著成就的原因.     

截断平顶高斯光束M2因子的比较研究

使用熵束宽、渐近分析和环围功率法对截断平顶高斯光束的束腰宽度w、远场发散角θ0和M²因子作了比较研究.结果表明:按不同束宽定义得到的截断平顶高斯光束的w、θ0和M²因子不同,且与截断参量a/w0(a为光阑半宽度,w0为平顶高斯光束初始束腰宽度)有关.随a/w0的增加,三种方法计算得到的w、θ0和M²都分别趋于某常量.