在MRI造影剂(CA)的研究领域中,通常寻求两亲顺磁性络合物以增加血浆半衰期和高弛豫值,但是迄今为止已经报道了基于两亲Mn 2+的CA的有限实例。在这项工作中,包含一个或两个脂族链的六个原始两亲性配体(三个EDTA状配体和三个1,4-DO2A衍生物)的Mn 2+复合物被评估为潜在的MRI造影剂并进行了比较。由于超分子聚集体的分子翻滚速率增加,强烈的自缔合成胶束导致弛豫性(r 1)增强(相对于MnEDTA约80%)。对于双取代系统,由于螯合剂围绕脂肪族侧链的局限旋转,r 1的增益要高得多(r 1在12.6-18.4 mM -1 s -1的范围内,是单链胶束的2-3倍EDTA系统)。此外,这些两亲性螯合物以10 4 –10 5 M -1的缔合常数K A与人血清白蛋白(HSA)紧密结合。所得的超分子加合物达到了显着的弛豫值,对于MnEDTA状螯合物而言,在50-60 mM -1 s -1范围内,在27-30
Facile one-pot synthesis of α-bromoketones from olefins using bromide/bromate couple as a nonhazardous brominating agent
作者:Rajendra D. Patil、Girdhar Joshi、Subbarayappa Adimurthy、Brindaban C. Ranu
DOI:10.1016/j.tetlet.2009.03.047
日期:2009.5
A new method for the preparation of α-bromoketones from olefins using bromide/bromate couple as a nonhazardous brominating agent has been developed. Several α-bromoketones were successfully prepared from a variety of olefins by this method. This procedure is an alternative to conventional molecular bromine.
Synthesis and Application of Poly(diallyldimethylammonium tribromide) as a Novel Polymeric Brominating Agent
作者:Mahdavi Hossein、Kachoei Zahra
DOI:10.1002/cjoc.201090367
日期:2010.11
In this study, the synthesis and applications of a new supported tribromide reagent based on poly(diallyldimethylammonium chloride) is reported. This supported tribromide is used in α‐bromoacetalization of ketones, bromination of alkenes and regioselective bromination of activated aromatic compounds. This method is mild and no Br2 and HBr were used. Other advantages of this reagent are stability, high
A novel silver halide photographic element which contains a nondiffusible complex capable of releasing a diffusible, photographically useful material is disclosed. Said nondiffusible complex becomes active for ligand exchange upon reduction under alkalin conditions to release a diffusible, photographically useful material, said complex being represented by the following formula: ##STR1## wherein La is a quadridentate ligand group; Lb is a didentate ligand group; BALL is a ballast group; PHOTO is a photographically useful material group; Y is a counter ion; and r is the number of counter ions necessary for neutralizing the electric charge on the CO(III) complex.
Method and device for continuous determination of lubricating oil consumption of an internal combustion engine
申请人:Delvigne Thierry
公开号:US20050268692A1
公开(公告)日:2005-12-08
The invention relates to a method and device for the continuous determination of the lubricating oil consumption of an internal combustion engine. The inventive method consists in: placing a determined quantity of at least one radioactive tracer in the lubricating oil of which the consumption is to be measured; and measuring the quantity of radioactive tracer(s) present in the gases released from the engine (
2
), said measurement being taken downstream of the engine. According to the invention, the quantity of radioactive tracer(s) of the lubricating oil present in the gases released from the engine (2) is measured as follows: the gases are brought into contact with a trap (
7
) which can physically trap the radioactive tracer particles, the radiation from the trap is measured using a detector (
10
) which is sensitive to radiation emitted by the trapped radioactive tracer(s) and the measurements taken by the detector (
10
) are sent to a programmed computer which can convert said measurements into the lubricating oil consumption rate of the engine.