爆炸磁压缩发生器爆炸管运动研究

 报导了对爆炸磁压缩发生器(MFCG)的爆炸管进行的爆轰试验结果。用电子学方法测试了爆炸管采用的粉状RDX炸药的爆轰速度;采用高速分幅摄影方法,观测了爆炸管在管内RDX炸药爆轰产物驱动下的膨胀运动过程,测试了膨胀角、对称性和膨胀速度。试验表明,爆炸管在膨胀至 3倍初始半径内未发现破裂现象,其性能满足MFCG的设计要求。     

一致凸Banach空间中渐近非扩张映象的几乎轨道的渐近行为

设Ｘ是有Ｆｒéｃｈｅｔ可微范数的一致凸Ｂａｎａｃｈ空间，Ｃ是Ｘ的有界闭凸子集，Ｔ：Ｃ→Ｃ是一个渐近非扩张映象．证明了，如果｛ｘ_ｎ：ｎ≥１｝是Ｔ的几乎轨道，则序列｛ｘ０｝弱几乎收敛到集合∩from∞to(ｎ＝１)ｃｏ｛ｘ_i：ｉ≥ｎ｝∩Ｆ（Ｔ）的唯一点，其中，Ｆ（Ｔ）是Ｔ的不动点集．     

On a Generalization of Waring''s Formula

[1]gives a generalization of Waring's formula. Here we show that Konvalina's extension is a straightforward consequence of the Waring formula itself.     

氧化还原功能纤维的研究Ⅵ．含胺基及乙二胺基功能纤维与Au~（3＋）的氧化还原反应机理

本文通过红外光谱分析、元素分析及光电子能谱分析等实验手段证实胺基及乙二胺基纤维中氧原子与Ａｕ３＋未发生氧化还原反应，而邻近的碳原子被氧化成羟基碳或羰基碳，并伴有氮原子的脱落，而部分吸附态Ａｕ３＋最终被还原成Ａｕ０。     

Search for global minimum geometries for medium sized germanium clusters: Ge12-Ge20

We have performed an unbiased search for the global minimum geometries of small-to-medium sized germanium clusters Gen(12< or =n< or =18) as well as a biased search (using seeding method) for Gen(17< or =n< or =20). We employed the basin-hopping algorithm coupled with the plane-wave pseudopotential density functional calculations. For each size, we started the unbiased search with using several structurally very different initial clusters, or we started the biased search with three different seeds. Irrespective of the initial structures of clusters we found that the obtained lowest-energy clusters of the size n=12-16 and 18 are the same. Among them, the predicted global minima of Gen(12< or =n< or =16) are identical to those reported previously [Shvartsburg et al., Phys. Rev. Lett. 83, 167 (1999)]. For n=17-20, we have identified two or three nearly isoenergetic low-lying isomers (for each size) that compete for the global minimum. Nearly all the low-lying clusters in the size range of 12< or =n< or =20 contain the tri-caped trigonal prism motif and are all prolate in geometry, in agreement with the experiment.     

Synthesis of crescent aromatic oligoamides

[structures: see text] This article describes the synthetic procedures for the preparation of crescent (and helical) aromatic oligoamides developed in recent years in our laboratory. The large-scale preparation of a variety of monomers derived from various tetrasubstituted benzenes is presented. Three different strategies for constructing various oligomers consisting of meta- and meta/para-linked benzene residues are discussed. Factors affecting coupling efficiency and yields are analyzed. The developed synthetic methods have provided the basis for the preparation of longer oligomers and for the development of solid-phase synthesis.     

Ionic liquid high temperature gas sensors

An ionic liquid piezoelectric gas sensor was demonstrated for detection of polar and nonpolar organic vapors at high temperature with fast linear and reversible response.     

Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights,which can be arbi- trarily dependent of each other.Then the applications to ruin probabilities in a discrete time risk model with dependent stochastic returns are considered.     

1,4-二(萘[2,1-d]并(噁)唑-2’)苯为敏感试剂的荧光光纤传感器测定甲硝唑的研究

将1,4-二(萘[2,1-d]并(口恶)唑-2’)苯(BNOB)包埋在增塑的聚氯乙烯膜中,基于甲硝唑对BNOB的可逆猝灭,研制了一种甲硝唑荧光光纤传感器,传感器可逆性好,响应时间小于40s,响应线性范围为8.0×1O~(-6)～1.0×10~(-(?))mol·L~(-1),检出限为4.O×10~(-6)mol·L~(-1),常见的无机离子、药物不干扰甲硝唑的测定,传感器用于药品制剂中甲硝唑的测定,结果与药典法一致.     

Improvement of amorphous silicon n-i-p solar cells by incorporating double-layer hydrogenated nanocrystalline silicon structure

We develop a double-layer p-type hydrogenated nanocrystalline silicon (p-nc-Si:H) structure consisting of a low hydrogen diluted i/p buffer layer and a high hydrogen diluted p-layer to improve the hydrogenated amorphous silicon (a-Si:H) n-i-p solar cells. The electrical, optical and structural properties of p-nc-Si:H films with different hydrogen dilution ratio (R_H) are investigated. High conductivity, low activation energy and wide band gap are achieved for the thin films. Raman spectroscopy and high-resolution transmission electron microscopy (HRTEM) analyses indicate that the thin films contain nanocrystallites with grain size around 3-5 nm embedded in the amorphous silicon matrix. By inserting a p-nc-Si:H buffer layer at the i/p interface, the overall performance of the solar cell is improved significantly compared to the bufferless cell. The improvement is correlated with the reduction of the density of defect states at the i/p interface.