期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
氯化钠晶体的手征特性研究
1
作者 颜飞彪 陶卫东 +1 位作者 白贵儒 陆祖康 《光电子技术与信息》 CAS 2005年第2期103-104,109,共3页
在对大学生的光学教学与实践中,实验的地位是至关重要的。通过对氯化钠晶体的手征特性的教学与实验研究,不仅使同学们掌握了一些光学研究的实验手段,而且使他们意识到实验是检验理论正确性唯一标准的深远含义。
关键词 光学教学 实验 手征特性
下载PDF
完全填充手征等离子体波导的电磁波传输特性 被引量:1
2
作者 杨世信 龚建民 +2 位作者 盛克敏 方寅 任朗 《强激光与粒子束》 EI CAS CSCD 北大核心 1998年第1期70-74,共5页
应用纵向分量法推导出了柱坐标系下均匀手征等离子体媒质中电磁场的横向分量与纵向分量的关系,并导出了纵向分量满足的波动方程,在柱坐标系下求解该波动方程并应用圆柱状导体边界条件导出了完全填充手征等离子体金属圆波导的色散方程... 应用纵向分量法推导出了柱坐标系下均匀手征等离子体媒质中电磁场的横向分量与纵向分量的关系,并导出了纵向分量满足的波动方程,在柱坐标系下求解该波动方程并应用圆柱状导体边界条件导出了完全填充手征等离子体金属圆波导的色散方程。数值求解色散方程给出了模式色散图。 展开更多
关键词 等离子体 柱形波导 手征特性 电磁波传输
下载PDF
D_2-C_(84)的手征同素异形体
3
作者 杨丽佳 姜宗福 《国防科技大学学报》 EI CAS CSCD 北大核心 1996年第1期124-128,共5页
本文指出D2-C84具有手征特性,这个结论可以很好地解释为什么实验上获得的D2-和D2d-C84的产量之比为2:1.我们以C84为例就福勒烯(fullefene)的同素异形体(isomer)的结构、对称性及稳定性进行... 本文指出D2-C84具有手征特性,这个结论可以很好地解释为什么实验上获得的D2-和D2d-C84的产量之比为2:1.我们以C84为例就福勒烯(fullefene)的同素异形体(isomer)的结构、对称性及稳定性进行了定性的讨论。 展开更多
关键词 手征特性 同素异形体 富勒烯 D2-C84 碳84
下载PDF
Multifocal stenosing ulceration of the small intestine 被引量:5
4
作者 Hugh James Freeman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第39期4883-4885,共3页
Several reports have described an apparently uncommon clinicopathological disorder that is characterized by multifocal stenosing small-intestinal ulceration.Compared to Crohn's disease,the ulcers are not transmura... Several reports have described an apparently uncommon clinicopathological disorder that is characterized by multifocal stenosing small-intestinal ulceration.Compared to Crohn's disease,the ulcers are not transmural and typically remain shallow,and involve only the mucosa and submucosa.The disorder seems to be localized in the jejunum and proximal ileum only,and not the distal ileum or colon.Only nonspecif ic inflammatory changes are present without giant cells or other typical features of granulomatous inflammation.Most patients present clinically with recurrent obstructive events that usually respond to steroids,surgical resection,or both.With the development of newer imaging modalities to visualize the small-intestinal mucosa,such as double-balloon enteroscopy,improved understanding of the long-term natural history of this apparently distinctive disorder should emerge. 展开更多
关键词 ULCER STENOSIS Intestinal diseases Small intestine Crohn's disease
下载PDF
Asymptotic Behavior of Soliton Solutions with a Double Spectral Parameter for Principal Chiral Field
5
作者 SONG Quan-Fu ZHOU Zi-Xiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期977-980,共4页
The soliton solutions with a double spectral parameter for the principal chiral field are derived by Darboux transformation. The asymptotic behavior of the solutions as time tends to infinity is obtained and the speed... The soliton solutions with a double spectral parameter for the principal chiral field are derived by Darboux transformation. The asymptotic behavior of the solutions as time tends to infinity is obtained and the speeds of the peaks in the asymptotic solutions are not constants. 展开更多
关键词 principal chiral field asymptotic solutions
下载PDF
A special recurrent pattern in small hepatocellular carcinoma after treatment:Bile duct tumor thrombus formation 被引量:8
6
作者 Qing-Yu Liu Dong-Ming Lai Chao Liu Lei Zhang Wei-Dong Zhang Hai-Gang Li Ming Gao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第43期4817-4824,共8页
AIM:To investigate the clinicopathologic features of bile duct tumor thrombus(BDTT) occurrence after treatment of primary small hepatocellular carcinoma(sHCC) .METHODS:A total of 423 patients with primary sHCC admitte... AIM:To investigate the clinicopathologic features of bile duct tumor thrombus(BDTT) occurrence after treatment of primary small hepatocellular carcinoma(sHCC) .METHODS:A total of 423 patients with primary sHCC admitted to our hospital underwent surgical resection or local ablation.During follow-up,only six patients were hospitalized due to obstructive jaundice,which occurred 5-76 mo after initial treatment.The clinicopathologic features of these six patients were reviewed.RESULTS:Six patients underwent hepatic resection(n=5) or radio-frequency ablation(n=1) due to primary sHCC.Five cases had an R1 resection margin,and one case had an ablative margin less than 5.0 mm.No vascular infiltration,microsatellites or bile duct/canaliculus affection was noted in the initial resected specimens.During the follow-up,imaging studies revealed a macroscopic BDTT extending to the common bile duct in all six patients.Four patients had a concomitant intrahepatic recurrent tumor.Surgical re-resection of intrahepatic recurrent tumors and removal of BDTTs(n=4) ,BDTT removal through choledochotomy(n= 1) ,and conservative treatment(n=1) was performed.Microscopic portal vein invasion was noted in three of the four resected specimens.All six patients died,with a mean survival of 11 mo after BDTT removal or conservative treatment.CONCLUSION:BDTT occurrence is a rare,special recurrent pattern of primary sHCC.Patients with BDTTs extending to the common bile duct usually have an unfavorable prognosis even following aggressive surgery.Insufficient resection or ablative margins against primary sHCC may be a risk factor for BDTT development. 展开更多
关键词 Small hepatocellular carcinoma Recurrence Bile ducts Jaundice Diagnosis
下载PDF
Total synthesis of proposed structures ofjiangrines C and D
7
作者 Zhijiang Zhang Bo Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第9期1205-1210,共6页
On the basis of the proposed structures of jiangrines C and D, a synthetic strategy was initiated from D-glyceraldehyde acetonide,a readily available chiral material. Through a linear seven-step synthesis, the target ... On the basis of the proposed structures of jiangrines C and D, a synthetic strategy was initiated from D-glyceraldehyde acetonide,a readily available chiral material. Through a linear seven-step synthesis, the target molecules were accomplished. However, all characteristic data of the synthetic 3 and 4 were found to be different from those of natural jiangrines C and D. Accordingly, the molecular structures of jiangrines should be revised and a possible molecular skeleton for them was proposed. 展开更多
关键词 PYRROLE ALKALOID jiangrine total synthesis
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部