检索结果-南通市图书馆

Intensity Dependent Nonlinear Absorption in Direct and Indirect Band Gap Crystals under Nano and Picosecond Z-Scan

Optics and Photonics Journal 2012年第2期2卷 98-104页

作者： Dimple Sharma Poonam gaur Bharam Pal Malik Nageshwar Singh arun gaur Department of Physics Deenbandhu Chhotu Ram University of Science and Technology (D.C.R.U.S.T) Murthal Sonipat India Department of Physics Hindu P.G. College Sonipat India Laser Systems Engineering Division (L.S.E.D.) Raja Rammanna Centre for Advanced Technology (CAT) Indore India

The nonlinear absorption properties of direct (GaN) and indirect (CdI2) band gap crystals have been studied by using an open aperture Z-scan technique under fundamental (1064 nm) and frequency doubled (532 nm) wavelength respectively with 10 ns or 60 ps pulse durations. Direct band gap crystal exhibits two and three photon absorption at all input irradiances. On the other hand, at low input irradiance the indirect band gap crystal exhibits saturable absorption (SA). At higher input irradiances two and three photon absorption becomes dominant. A monotonic increase of the nonlinear absorption coefficients with increasing laser pulse duration from 60 ps to 10 ns is observed for GaN and CdI2 crystals.

关键词： Direct and Indirect Band Gap Crystals Two Photon Absorption Three Photon Absorption Saturated Absorption

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect feeding deterrent and growth inhibitory activities of scopoletin isolated from Artemisia annua against Spilarctia obliqua （Lepidoptera： Noctuidae）

引用

Insect Science 2011年第2期18卷 189-194页

作者： arun Kumar Tripathi Rajendra Singh Bhakuni Shikha Upadhyay Rashmi gaur Central Institute of Medicinal and Aromatic Plants Lucknow India

Artemisia annua （Asteraceae） is well known for its antimalarial activities due to presence of the compound artemisinin. We isolated a methoxy coumarin from the stem part of A. annua and confirmed its identity as scopoletin through mass spectral data. The structure was established from 1H-nuclear magnetic resonance （NMR）, 13C-NMR. The compound scopoletin was evaluated for its feeding deterrence and growth inhibitory potential against a noxious lepidopteran insect, Spilartctia obliqua Walker. Scopoletin gave FD50（feeding deterrence of 50%） value of 96.7 μg/g diet when mixed into artificial diet. S. obliqua larvae （12-day-old） exposed to the highest concentration （250μg/g diet） of scopoletin showed 77.1% feeding-deterrence. In a growth inhibitory assay, scopoletin provided 116.9% growth inhibition at the highest dose of 250μg/g diet with a GI50 （growth inhibition of 50%） value of 20.9μg/g diet. Statistical analysis showed a concentrationdependent dose response relationship toward both feeding deterrent and growth inhibitory activities. Artemisinin is found mainly in the leaves of A. annua and not in the stems, which are typically discarded as waste. Therefore identification of scopoletin in stems of A. annua may be important as a source of this material for pest control.

关键词： Artemisia annua feeding deterrent growth inhibitor scopoletin Spilartiaobliqua

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

商用区块链

引用

作者： (美)贾伊·辛格·艾冉(Jai Singh arun)，(美)杰里·科莫(Jerry Cuomo)，(美)尼丁·高尔(Nitin gaur)

来源：南通市图书馆图书评论

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：