Comparison of(η~6-Fluoroarene)tricarbonylchromium Complexes with Their Chloro-analogs in Radical Aromatic Substitutions

Reactions of fluoroarene-Cr(CO)_3 complexes with SmI_2 andcarbonyl compounds in THF/HMPA at-40— -60℃ affordedthe corresponding radical aromatic substitution products in highyield. Compared to the corresponding chloroarene-Cr.(CO)_3complexes, fluoroarene-Cr(CO)_3 complexes showed a higher ef-ficiency and slightly lower regioselectivity.     

角膜内皮细胞载体膜片的性质研究及移植试验

利用溶剂浇铸/颗粒沥滤技术制备出壳聚糖和硫酸软骨素共混膜, 研究了共混膜的透光性、 表面结构、 红外图谱、 X-射线衍射图谱以及生物相容性和生物降解性. 结果表明, 共混膜透明度高, 结构均匀, 孔隙大小合适, 壳聚糖分子与硫酸软骨素达到分子水平分散, 且分子间存在较强的相互作用, 共混膜具有良好的生物相容性和生物降解性. 以共混膜为载体培养兔角膜内皮细胞, 结果表明, 共混膜非常适合角膜细胞贴附生长, 10 d内长成良好单层细胞. 将载有角膜内皮细胞的膜片植入内皮缺损兔眼中, 在56 d内术眼基本保持透明, 之后角膜水肿, 逐渐模糊并出现新生血管, 在230 d时术眼新生血管基本消失, 角膜恢复透明.     

平面Gunn器件中的雪崩弛豫振荡

为了寻找一个高效率的固体振荡器,我们研究了Gunn二极管中的雪崩弛豫振荡。本文描述有源区比较短的平面Gunn器件,在数倍于阚值的强场下工作时出现的雪崩弛豫振荡,这种振荡现象归结于畴雪崩后的电子空穴对的周期性出现和消失。它的振幅可以比Gunn振荡大得多,而频率比Gunn振荡小几倍,并且受外电路参数影响很大,在负载匹配好的情况下,粗略地测得总效率可达36％。     

On the Drinfeld-Sokolov hierarchy of type E(1)6 and its topological solution

In this paper we report some explicit evolutionary PDEs of the Drinfeld-Sokolov hierarchy of type E(1)6,and show how the unknown functions in these PDEs are rel...     

Angular control of multi-mode resonance frequencies in obliquely deposited CoZr thin films with rotatable stripe domains

We investigate the angular-dependent multi-mode resonance frequencies in CoZr magnetic thin films with a rotatable stripe domain structure.A variable range of multi-mode resonance frequencies from 1.86 GHz to 4.80 GHz is achieved by pre-magnetizing the CoZr films along different azimuth directions,which can be ascribed to the competition between the uniaxial anisotropy caused by the oblique deposition and the rotatable anisotropy induced by the rotatable stripe domain.Furthermore,the regulating range of resonance frequency for the CoZr film can be adjusted by changing the oblique deposition angle.Our results might be beneficial for the applications of magnetic thin films in microwave devices.     

Temperature-Dependent Raman Study on Vibrational Modes in LiTaO3

In this paper the results of temperature-dependent Raman study on the vibrational modes in LiTaO₃ crystals are presented. It is found that the two low-frequency A₁ modes show significant changes during the temperature changing process. “Modes softening” and “frequency-repulsion” effect was observed and dicussed.     

Infinite-dimensional Frobenius manifolds underlying the Toda lattice hierarchy

Following the approach of Carlet et al. (2011) [9], we construct a class of infinite-dimensional Frobenius manifolds underlying the Toda lattice hierarchy, which are defined on the space of pairs of meromorphic functions with possibly higher-order poles at the origin and at infinity. We also show a connection between these infinite-dimensional Frobenius manifolds and the finite-dimensional Frobenius manifolds on the orbit space of extended affine Weyl groups of type A defined by Dubrovin and Zhang.     

Correction to: Relating Darcy-Scale Chemical Reaction Order to Pore-Scale Spatial Heterogeneity

Transport in Porous Media -     

Absorption Spectrum Study on Colloidal Centers in KCl:NCO:K

The absorption spectrum study on metallic colloidal centers in KCl:NCO:K crystals have been performed as a function of annealing temperature in the temperature range of 500–750K. Conversion process between F-centers and colloidal centers was observed and it is found that the NCO ions play an important role in the formation and stability of aggregative centers in alkali halides.