排序方式: 共有36条查询结果,搜索用时 15 毫秒
21.
Munshi G Mustafa Sudhir Raniwala T Awes B Rai RS Bhalerao JG Contreras RV Gavai SK Ghosh P Jaikumar GC Mishra AP Mishra H Mishra B Mohanty J Nayak J-Y Ollitrault SC Phatak L Ramello R Ray PK Sahu AM Srivastava DK Srivastava VK Tiwari 《Pramana》2006,67(5):961-981
This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and
work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported. 相似文献
22.
A novel iminium ion cascade reaction has been developed that allows for the stereoselective synthesis of a variety of substituted aza-fused bicycles. The combination of amino allylsilanes and aldehydes (or ketones) was used to synthesize a number of quinolizidines and indolizidines in a one-pot reaction sequence. This technology has been used to effect the facile syntheses of several indolizidine and quinolizidine natural products including (±)-epilupinine, (±)-tashiromine, and (−)-epimyrtine. Substrate scope has been examined varying the type of amino allylsilanes (primary, secondary, and conjugated) and carbonyl compounds (aldehydes and ketones) to give a variety of fused ring structures. Varying the components chosen allows for the inclusion of synthetically useful functional groups at different positions on the core structure. The methodology has been used to construct the tricyclic core structures present in the cylindricine family and halichlorine. 相似文献
23.
Bishop S Azuma RE Buchmann L Chen AA Chatterjee ML D'Auria JM Engel S Gigliotti D Greife U Hernanz M Hunter D Hussein A Hutcheon D Jewett C José J King J Kubono S Laird AM Lamey M Lewis R Liu W Michimasa S Olin A Ottewell D Parker PD Rogers JG Strieder F Wrede C 《Physical review letters》2003,90(16):162501
The 21Na(p,gamma)22Mg reaction is expected to play an important role in the nucleosynthesis of 22Na in oxygen-neon novae. The decay of 22Na leads to the emission of a characteristic 1.275 MeV gamma-ray line. This report provides the first direct measurement of the rate of this reaction using a radioactive 21Na beam, and discusses its astrophysical implications. The energy of the important state was measured to be E(c.m.)=205.7+/-0.5 keV with a resonance strength omegagamma=1.03+/-0.16(stat)+/-0.14(sys) meV. 相似文献
24.
Diana C. Knyazeva Flora W. Kimani Jean-Laurent Blanche John C. Jewett 《Tetrahedron letters》2017,58(28):2700-2702
Alkyl diazonium ions are among the most reactive alkylating agents in the synthetic chemists’ arsenal. That said, there are precious few methods by which one can selectively and safely utilize this chemistry. Herein, we show the use of a bench stable hexyl triazabutadiene as a source of reactive diazonium ions that undergo substitution chemistry with weak nucleophiles, such as carboxylates and even sulfonates. In the absence of a nucleophile, elimination was observed to occur. To overcome issues stemming from side-product inhibition of the reaction, we show that the triazabutadiene can be pre-activated with tosyl isocyanate. 相似文献
25.
Cyclooctyne-based probes that become fluorescent upon reaction with azides are important targets for real-time imaging of azide-labeled biomolecules. The concise synthesis of a coumarin-conjugated cyclooctyne, coumBARAC, that undergoes a 10-fold enhancement in fluorescence quantum yield upon triazole formation with organic azides is reported. The design principles embodied in coumBARAC establish a platform for generating fluorogenic cyclooctynes suited for biological imaging. 相似文献
26.
本文对目前广泛应用于结构非线性分析之中的弧长法进行改进。改进后的弧长法除保持原有优点外,能够在自动跟踪结构非线性平衡路径的同时,进一步求得位于结构平衡睡径任一区段的任意预先指定的荷载水平及相应的变形。本文的方法可以推广应用于求解预先指定的应力或位移。数值算例表明了本文方法的计算精度、效率及可靠性。 相似文献
27.
Heinrich JG Matthies Qiao Han Angela Shields Jane Wright Jessica L Moore Danny G Winder Aurelio Galli Randy D Blakely 《BMC neuroscience》2009,10(1):65-19
Background
Reuptake of synaptic norepinephrine (NE) via the antidepressant-sensitive NE transporter (NET) supports efficient noradrenergic signaling and presynaptic NE homeostasis. Limited, and somewhat contradictory, information currently describes the axonal transport and localization of NET in neurons. 相似文献28.
Water‐Soluble Triazabutadienes that Release Diazonium Species upon Protonation under Physiologically Relevant Conditions
下载免费PDF全文
![点击此处可从《Angewandte Chemie (International ed. in English)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Flora W. Kimani Dr. John C. Jewett 《Angewandte Chemie (International ed. in English)》2015,54(13):4051-4054
Triazabutadienes are an understudied structural motif that have remarkable reactivity once rendered water‐soluble. It is shown that these molecules readily release diazonium species in a pH‐dependent manner in a series of buffer solutions with pH ranges similar to those found in cells. Upon further development, we expect that this process will be well suited to cargo‐release strategies and organelle‐specific bioconjugation reactions. These compounds offer one of the mildest ways of generating diazonium species in aqueous solutions. 相似文献
29.
30.