A solar radio moving type IV burst of expanding arches type involving multi-sources

A complex solar radio moving type IV burst was observed on 23 September 1998 with the broadband (1.0–2.0 GHz and 2.6–3.8 GHz) spectrometers with high temporal and spectral resolutions at National Astronomical Observatories of China (NAOC). Comparing to the high spatial resolution data of Siberian Solar Radio Telescope (SSRT), we find that this burst is a rare type of moving type IV burst which is caused by the expanding arches, and the spatial structure oscillations of the radio sources are related with the time structure pulsations of the radio emission. Furthermore, the burst is associated with the multiple quasi-periodic long-term pulsations, and this suggests the existence of multi-scale magnetic structures in a large expanding coronal arch. We think the moving type IV burst is due to the synchrotron emission of the energetic electrons trapped in the expanding arch, and the multiple quasi-periodic pulsations are due to the second harmonic plasma emission.     

高强混凝土弯压极限应变试验研究与计算

由于混凝土材料理化特性的差异,高强混凝土的弯压极限应变明显地小于普通混凝土,依据试验结果分析了高强混凝土的弯压极限应变变化规律,并给出了它的计算公式.     

Influence of fluoride on f-f transitions of Eu in LiEuM2O8 (M=Mo, W)

The influence of fluoride on the luminescence of LiEuM₂O₈ (M=Mo, W) was studied. LiEuMo₂O₈ and LiEuW₂O₈ formed the whole range of solid solutions, which emitted intense red luminescence under the excitations by 395, 465 and 535 nm wavelengths. When doped with fluoride, the materials also formed solid solutions and the luminescent intensity was remarkably enhanced. The phosphor with optimized compositions in this system would be a promising red component for solid-state lighting devices based on GaN light-emitting diodes.     

Stowage planning in maritime container transportation

We consider a stowage-planning problem of arranging containers on a container ship in the maritime transportation system. Since containers are accessible only from the top of the stack, temporary unloading and reloading of containers, called shifting, is unavoidable if a container required to be unloaded at the current port is stacked under containers to be unloaded at later ports on the route of the ship. The objective of the stowage planning problem is to minimize the time required for shifting and crane movements on a tour of a container ship while maintaining the stability of the ship. For the problem, we develop a heuristic solution method in which the problem is divided into two subproblems, one for assigning container groups into the holds and one for determining a loading pattern of containers assigned to each hold. The former subproblem is solved by a greedy heuristic based on the transportation simplex method, while the latter is solved by a tree search method. These two subproblems are solved iteratively using information obtained from solutions of each other. To see the performance of the suggested algorithm, computational tests are performed on problem instances generated based on information obtained from an ocean container liner. Results show that the suggested algorithm works better than existing algorithms.     

A completion of the spectrum for large sets of disjoint transitive triple systems

In this paper, we give a recursive construction from an LTTS(v + 2) to an LTTS(16v + 2) for v 3. Furthermore, the existence of LTTS(2ⁿ + 2) is proved. Thereby, we completely solve the existence problem of LTTS)(v) (large set of pairwise disjoint transitive triple systems of order v).     

B值鞅型序列的一些极限定理

本文讨论了一些B值鞅型序列的强大数定律 ,弱大数定律 ,Lr收敛性及完全收敛性 ,推广了许多熟知的结果 .     

催化动力学光度法测定痕量钴(Ⅱ)

本法基于钴 (Ⅱ )对高碘酸钾氧化孔雀绿的催化作用 ,提出一种灵敏地测定痕量钴 (Ⅱ )的新方法。该方法线性范围在 0～ 0 8μg·2 5mL- 1 ,检测限为 2 1× 10 - 1 0 g·mL- 1 。测定出反应表现活化能Ea=37 94kJ·mol- 1 。此法用于茶叶、维生素B1 2 中钴的测定 ,结果满意     

Graphical operations on projective spaces

Motivated by the work of Crapo and Rota [6] on the lifting of a projective complex, we introduce a class of invariant operations associated to integral-weighted graphs, which we call graphical operations. Such operations generalize the sixth harmonic of a quadranguler set on a projective line. We determine the expansion of the graphical operations in terms of multi-linear bracket polynomials in a Grassmann-Cayley algebra. Reducibility and compositions of such invariant operations are also investigated with a number of examples.Supported by Courant Instructorship, New York University.     

双齿配体—1,2—C_6H_4SX(X=O,S)的钴化合物~1H NMR研究

以~1H NMR谱学和磁化率对一些含邻苯二硫酚或巯基苯酚配体的钴化合物的磁性作了研究,并讨论了它们的电子结构。     

双齿配位过渡金属化合物化学——Ⅲ.钒的邻巯基苯酚配合物的顺磁谱研究

测定了二个顺磁性化合物(Ph_1P)[V_2(mp)_6](Ⅰ)和(Ph_4P)_2[NaV(mp)_3 (MeCN)(MeOH)](Ⅱ)(H_2mp=邻巯基苯酚,o-HO_1C_6H_4SH)的固态和/或溶液中的顺磁波谱。(Ⅰ)的77K固态谱及(Ⅱ)的室温固态谱均经模拟计算,认为它们的钒原子处在S=l/2的Ⅰ=7/2状态,(Ⅱ)的低温(77K)溶液谱(乙腈)与Ⅱ的固态谱相同,均有特征的八条精细结构,认为非配对电子基本上定域在钒原子的周围。