Application of high field spectroscopic imaging in the evaluation of temporal lobe epilepsy

Previous spectroscopic imaging studies of temporal lobe epilepsy have used comparisons of metabolite content or ratios to lateralize the seizure focus. Although highly successful, these studies have shown significant variations within each of the groups of healthy subjects and patients. This variation may arise from the natural differences seen in metabolite concentration in gray and white matter, the complex anatomy seen about the hippocampus, and the large voxels typically employed at 1.5 T. Using a 4.1 T whole body system, we have acquired spectroscopic images with 0.5 cc nominal voxels (1 cc after filtering) to evaluate the regional variation in metabolite content of the hippocampus, temporal gray and white matter, midbrain, and cerebellar vermis. Using a threshold value of 0.90 for CR/NAA, a value 90% of all normal hippocampal voxels lay below, we have correctly identified the presence of epileptogenic tissue in patients with unilateral as well as bilateral seizures. By using comparisons to healthy values of the CR/NAA ratio, this method enables the visualization of bilateral disease and provides information on the extent of gray matter involvement.     

Surface Superconductivity¶in Applied Magnetic Fields Above HC2

In this paper we study the surface superconductivity phenomenon of type 2 superconductors under applied magnetic fields above the critical field . We show that, for a cylindrical superconductor of infinite height placed in a homogeneous applied magnetic field, H e ₃, with H lying in between and keeping away from and , superconductivity persists uniformly at a thin sheath surrounding the entire lateral surface of the sample. As the applied field decreases gradually, superconductivity in the surface sheath becomes strong and develops into a surface superconducting state, while the interior of the sample remains close to the normal state. Received: 21 May 2001 / Accepted: 11 February 2002     

塑料脱模剂一组分的光谱分析

柱层析色谱分离性能优良的新型塑料脱模剂，纯化后得一主要未知组分。用元素分析、红外光谱、核磁共振氢谱研究其结构特征，对其盐酸酸化前后红外光谱吸收峰及核磁带进行了归属分析并确定结构。结果表明，该组分为一表面活性剂N，N-二羟乙基十二烷基胺。这为新型脱模剂的产品开发提供了依据。     

Hydrogen energy and solid state fuel cells

This paper discusses hydrogen energy and the methods for production of hydrogen. It also provides a review of various materials which are hydrogen permeable. Previous studies on the proton-conducting ceramics and their properties are summarized. The principle of proton-conducting solid state fuel cell for conversing the energy of hydrogen containing fuel is described with a discussion of the advantages of proton-conducting ceramic fuel cells as compared to oxygen-ionic conducting fuel cells. The paper is concluded with a discussion of the major materials related technical challenges in the development of the proton-conducting ceramic fuel cells. Paper presented at the 97th Xiangshan Science Conference on New Solid State Fuel Cells, Xiangshan, Beijing, China, June 14–17, 1998.     

食管癌患者肿瘤组织中硒含量的调查测定

应用2，3-二氨基萘荧光测定法对36例食管癌患者癌组织与癌旁组织及血清中硒的含量进行了测定。结果表明，癌组织中硒含量平均为1．325±0．81μg／g干重，癌旁组织为0．893±0．68μg／g干重，两者差异显著（P＜0．05）；血清中硒含量为0.6033±0．0520μmol／L，对照组20例献血员血清为0．8034±0．0650μmol／L，亦有显著性差异（P＜0．05）。提示硒在抗肿瘤的过程中有一定作用。     

弯曲波导之间的耦合分析

采用极坐标下的光束传播法分析了两条平行变曲波导的中心间距、曲率半径等因素对模式耦合的影响,得到了耦合长度、耦合强度随中心间距、曲率半径的变化规律,并将直波导作为变曲波导的一种特殊情况进行了分析.     

电磁波在大气层人造等离子体中的衰减特性

利用洛沦兹模型来研究大气层人造非均匀等离子体的电磁响应特性,讨论了电磁波频率、等离子体密度及电子碰撞频率对电磁波衰减特性的影响.结果表明,电磁波在长波长区域及等离子体密度大时,其能量衰减越快.当等离子体密度高时,电子温度越低,大气层高度越高,电磁波的能量衰减越快. 关键词： 电磁波 大气等离子体 能量衰减     

Shears band in the 105Sn nucleus

The structure of ¹⁰⁵Sn has been investigated through the ⁵⁰Cr(⁵⁸Ni,2pn) reaction at a beam energy of 210 MeV. In addition to an extension of the spherical level scheme, a regular sequence of dipole transitions has been found. The experimental results are in agreement with the prediction of Tilted Axis Cranking calculations, which satisfactorily explain the properties of the band.     

溶胶-凝胶法制备(Ba0.7Sr0.3)TiO3/LaNiO3异质薄膜及其结构和介电性质研究

采用改进的溶胶-凝胶方法在单晶Si(100)衬底上制备了介电性能优异的(Ba_0.7Sr_0.3)TiO₃/LaNiO₃异质薄膜.实验发现，在750 ℃下 、O₂气氛中晶化的LaNiO₃薄膜的电阻率最小.C-V与I-V特性测量表明(Ba_0.7Sr_0.3)TiO₃薄膜具有优异的介电性能，在频率为50kHz、零偏压下的相对介电常数ε_r>300，偏压为6V时漏电流密度J_L<1.2×10^-6A/cm². 关键词： xSr_1-x)TiO_３铁电薄膜')" href="#">(Ba_xSr_1-x)TiO_３铁电薄膜 ３底电极')" href="#">LaNiO３底电极 溶胶-凝胶法