英语翻译3.4.Elucidating the possible oxidation of Sn2+ within Sn–HEDP and Sn–PEI-MP complexesThere were no changes in the 31P NMR spectra of samples of Sn(II) with HEDP or PEI-MP overnight,hence we can assume that no oxidation of Sn2+ occurre

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英语翻译3.4.Elucidating the possible oxidation of Sn2+ within Sn–HEDP and Sn–PEI-MP complexesThere were no changes in the 31P NMR spectra of samples of Sn(II) with HEDP or PEI-MP overnight,hence we can assume that no oxidation of Sn2+ occurre

英语翻译3.4.Elucidating the possible oxidation of Sn2+ within Sn–HEDP and Sn–PEI-MP complexesThere were no changes in the 31P NMR spectra of samples of Sn(II) with HEDP or PEI-MP overnight,hence we can assume that no oxidation of Sn2+ occurre
英语翻译
3.4.Elucidating the possible oxidation of Sn2+ within Sn–HEDP and Sn–PEI-MP complexes
There were no changes in the 31P NMR spectra of samples of Sn(II) with HEDP or PEI-MP overnight,hence we can assume that no oxidation of Sn2+ occurred.Should this have been the case we would expect an increase in the ratio of intensities of the corresponding peaks,which would eventually approach the spectrum of the concerning Sn(IV)-complex at the respective pH.
In a study to understand the conditions needed for the oxidation of Sn2+ in the presence of HEDP,the complex was titrated with hydrogen-peroxide (30% H2O2).The metal to ligand ratio of 1:3 (pH 7.3) was chosen so as to limit any free/uncomplexed tin which would hydrolyze and precipitate out during the titrations.Throughout the investigation no precipitation was observed within the 1:3 mixtures,even over prolonged periods,which indicates that all tin was successfully complexed in solution and variations in the pH did not influence the Sn-ions directly–the [Sn–HEDP] complexes are stable enough to with-stand fluctuations in pH.Mixtures in which the metalion concentration was in excess,i.e.M:L > 1:1,exhibited immediate precipitation upon addition of NaOH.Precipitation eventually occurred in these solutions,even without any pH manipulation after a few hours – for both Sn2+ and Sn4+.
Oxidation of the tin in the [Sn(II)–HEDP]0 and the [Sn(II)–Sn(IV)–PEI-MP]4+ systems was induced by the addition of 30 μl ofH2O2,0.05 mol/L(Fig.9) and 0.010 mol/L(Fig.8) respectively.As expected,an increase in intensity of the resonances of the Sn(IV) complexes was observed in the case of HEDP,with a steady decrease in the intensity of the resonance at about 19 ppm,and for PEI-MP we observed the disappearance of the signal for the Sn(II) chelate,although only realizing some increase ( 35–45%) in intensity of the resonances for the Sn4+ complex.There is a increase in the free-ligand concentration ( 40– 55%),which could be due to the liberation of ligand that had been previously bound to Sn2+.The simultaneous increase in both amounts of [Sn(IV)–PEI-MP]2+ and free ligand after oxidation implies that the PEI-MP that had formerly been bound to Sn2+ is evenly distributed between Sn4+-bound and free ligand in solution.Furthermore,this would mean an increase in the free metal-ion concentration (i.e.at least half the tin-ions being released as reflected by the increase in free-ligand concentration).This is confirmed by the occurrence of slight precipitation upon completion of the oxidation driven by thereaction of Sn(IV) + 4OH-=Sn(OH)4(s).Approximately 1.6μmol of H2O2 per μmol of Sn2+ within the HEDP system,was needed to oxidize it in order to reach the equivalent complexation of Sn4+ at the same pH (Fig.9).For the [Sn(II)–PEI-MP]0 system 1.4μmol H2O2 per μmol Sn(II)–PEI-MP is needed.

英语翻译3.4.Elucidating the possible oxidation of Sn2+ within Sn–HEDP and Sn–PEI-MP complexesThere were no changes in the 31P NMR spectra of samples of Sn(II) with HEDP or PEI-MP overnight,hence we can assume that no oxidation of Sn2+ occurre
3.4 .澄清可能的氧化sn2 +内部锡hedp和SN -培国会议员配合
有没有变化,在核磁共振磷谱谱的样本锡(二)与hedp或培国会议员在一夜之间,因此,我们可以假定没有氧化sn2 +发生.应本已如此,我们预期在增加的比例,强度相应的高峰期,这将最终办法频谱的关于锡(四) -复杂的,在各自的pH值.
在一项研究,以了解所需的条件氧化sn2 +在在场的hedp ,复杂的是滴定氢过氧化物( 30 %过氧化氢) .金属配位体的比例1:3 ( pH值7.3 )被选为以便限制任何免费/ uncomplexed田将水解和沉淀在滴定法.在整个调查没有降水,观察内部的1:3的混合物,甚至超过长时间,这表明,所有田成功复合溶液中和变化,在pH值不影响锡离子直接[锡hedp ]复合是不够稳定,以与站的波动,pH值.混合物在其中金属离子浓度在过剩,即米:升> 1时01分,展示即时沉淀后,加入氢氧化钠.降水最终发生在这些解决方案,即使没有任何pH值操纵在数小时后-双方s n2+和s n4+ .
氧化锡在[锡(二) - hedp ] 0和[锡(二) -锡(四) -培国会议员] 4 +系统诱导增加3 0μ升o fh2o2,0 .05m ol/ L的(图9 )和0.010 mol / L的(图8 )分别.一如所料,增加在强度的共振锡(四)配合观察,在案件hedp ,稳步下降,在强度的共振,在约19 ppm ,使用和培国会议员,我们观察到的消失信号为锡(二)螯合,虽然只实现了一些增加( 35-45 % ),强度的共振为sn4 +复杂.是有增加,在自由配体的浓度( 40 -5 5% ) ,这可能是由于解放配体已被先前的约束,以s n2+ .同时,增加在这两个数额[锡(四) -培国会议员] 2 +和自由配体氧化后,意味着该培国会议员认为,以前的约束,以sn2 +是均匀分布之间的sn4 + -约束和自由配体的解决方案.此外,这将意味着增加,在自由金属离子浓度(即至少有一半是锡离子被释放所反映的增加,在自由配体的浓度).证实了这一点发生轻微沉淀完成后,氧化驱动thereaction锡(四) + 4oh - =锡(哦) 4 ( ) .大约1.6 μ mol过氧化氢% μ mol的sn2 +内部hedp系统,需要氧化它,以达到相等于络合的sn4 +在同一pH值(图9 ) .为[锡(二) -培国会议员] 0系统1.4 μ
参考

3.4. 阐明那里Sn2+在Sn-HEDP之内和Sn PEIMP复合体的可能的氧化作用是在Sn样品31P核磁共振光上的没有变化(II)与隔夜HEDP或PEI-MP,因此我们可以假设, Sn2+的氧化作用没有发生。 如果这是实际情形我们会期待在对应的峰顶的强度比率的增量,最终将接近有关的Sn (IV)的光谱-复合体在各自pH。 在研究了解条件为Sn2+的氧化作用需要在HEDP面前,复合体滴定了与氢...

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3.4. 阐明那里Sn2+在Sn-HEDP之内和Sn PEIMP复合体的可能的氧化作用是在Sn样品31P核磁共振光上的没有变化(II)与隔夜HEDP或PEI-MP,因此我们可以假设, Sn2+的氧化作用没有发生。 如果这是实际情形我们会期待在对应的峰顶的强度比率的增量,最终将接近有关的Sn (IV)的光谱-复合体在各自pH。 在研究了解条件为Sn2+的氧化作用需要在HEDP面前,复合体滴定了与氢过氧化物(30%水2)。 金属到ligand比率1:3 (酸碱度7.3)被选择以便限制所有自由或uncomplexed在滴定法期间,将水解并且沉淀的锡。 在调查中降雨雪未在1:3混合物,甚而长时间之内被观察,表明所有锡成功地是complexed在解答,并且在酸碱度上的变化没有在Sn离子directly-the的fluence [Sn-HEDP]复合体是足够稳定的承受fluctuations在pH。 metalion集中是过份的混合物,即。 M :L > 1:1,被陈列的直接降雨雪在NaOH的加法。 降雨雪在这些解答最终发生了,甚而,不用任何酸碱度操作在几个小时以后-为Sn2+和Sn4+。 锡在[Sn (II) - HEDP] 0和[Sn (II) - Sn (IV) - PEI-MP] 4+系统的氧化作用被30 μl导致ofH2O2, 0.05 mol/L的加法(。 9) 并且0.010 mol/L (。 8) 分别。 预期,在Sn (IV)复合体的共鸣的强度的增量被观察了在HEDP情况下,以在共鸣的强度的平稳的减退在大约19 ppm,并且为我们对Sn的PEI-MP (II)螯合观察信号失踪,虽然只体会一些增加(35-45%)在共鸣的强度为Sn4+复合体。 有在无ligand集中的增量(40 - 55%),可能归结于ligand解放早先一定到在两相当数量的Sn2+.The同时增量[Sn (IV) - PEI-MP] 2+,并且自由ligand,在氧化作用暗示之后以前一定对Sn2+在解答均匀地被分布在之间Sn4+跳起并且释放ligand的PEI-MP。 此外,这将意味在自由金属离子集中的增量(即。 一半被发布的至少锡离子,关于fl由在无ligand集中的增量ected)。 这是精读fi由轻微的降雨雪发生rmed在Sn (IV)的thereaction驾驶的氧化作用的完成+ 4OH-=Sn (OH) 4 (s)。 水2近似地1.6μmol每Sn2+ μmol在HEDP系统之内,是需要的氧化它为了到达Sn4+的等效络合在同样酸碱度(。 9). 为[Sn (II) - PEI-MP] 0系统1.4μmol水2每μmol Sn (II) - PEI-MP是需要的。

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