求高手翻译英文文献 嗯 关于DNA
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求高手翻译英文文献 嗯 关于DNA
The electronic absorption spectrum of 3 varies with the
acidity of the solution, revealing the presence of two
reversible protonation steps (Figure S1 in the Supporting
Information). As shown in Figure S1a in the Supporting
Information, when the volume of H2SO4 is increased
from 0.2% to 24.2%, the intensity of the bpy-based LC
transition decreases slightly and the dpqp ππ* band red
shifts and increases in intensity, with generation of an
isosbestic point at 361 nm.Afurther increase from 24.2%
to 64.6%H2SO4 results in the appearance of new features
in the absorption spectrum of 3 along with a new isosbestic
point at 395 nm (Figure S1b in the Supporting
Information). In contrast, only one isosbestic point at
365 nm was observed for 2 up to 73.4%H2SO4 (Figure S2
in the Supporting Information), with no significant
changes to the MLCT band of the complex. It should
be noted that the absorption spectrum of 1 does not vary
with pH under similar experimental conditions, consistent
with previous reports.40 The complete recovery of 3
from up to 64.4% H2SO4 can be achieved through the
addition of NaOH, showing a remarkable stability of the
complex in an acidic solution.
The red shift of the LC dpqp band from 365 to 417 nm
with increasing H2SO4 can be interpreted as resulting
from stabilization of the dpqp π* orbitals upon protonation,
as reported for other azaaromatic ligands.41 The
stabilization is anticipated to make the protonated dpqp
ligand easier to reduce, such that a red shift in the Ru f
dpqp MLCT transition is also expected. Although the
position of the protonation of 3 cannot be ascertained, it
is apparent that there are two protonation steps associated
with dpqp. For 2, protonation can only take place on
the central (phenazine) portion of dppz, and electronic
repulsion makes a second protonation on the same ring
unfavorable, although it may be possible under highly
acidic conditions.41 Multiple protonation steps on the
noncoordinated nitrogen atoms of azaaromatic ligands in
acidic media have been reported for [Ru(bpz)3]2þ (bpz=2,20-
bipyrazine) and [Ru(bpm)3]2þ (bpm=2,20-bipyrimidine).41,42
The electronic absorption spectrum of 3 varies with the
acidity of the solution, revealing the presence of two
reversible protonation steps (Figure S1 in the Supporting
Information). As shown in Figure S1a in the Supporting
Information, when the volume of H2SO4 is increased
from 0.2% to 24.2%, the intensity of the bpy-based LC
transition decreases slightly and the dpqp ππ* band red
shifts and increases in intensity, with generation of an
isosbestic point at 361 nm.Afurther increase from 24.2%
to 64.6%H2SO4 results in the appearance of new features
in the absorption spectrum of 3 along with a new isosbestic
point at 395 nm (Figure S1b in the Supporting
Information). In contrast, only one isosbestic point at
365 nm was observed for 2 up to 73.4%H2SO4 (Figure S2
in the Supporting Information), with no significant
changes to the MLCT band of the complex. It should
be noted that the absorption spectrum of 1 does not vary
with pH under similar experimental conditions, consistent
with previous reports.40 The complete recovery of 3
from up to 64.4% H2SO4 can be achieved through the
addition of NaOH, showing a remarkable stability of the
complex in an acidic solution.
The red shift of the LC dpqp band from 365 to 417 nm
with increasing H2SO4 can be interpreted as resulting
from stabilization of the dpqp π* orbitals upon protonation,
as reported for other azaaromatic ligands.41 The
stabilization is anticipated to make the protonated dpqp
ligand easier to reduce, such that a red shift in the Ru f
dpqp MLCT transition is also expected. Although the
position of the protonation of 3 cannot be ascertained, it
is apparent that there are two protonation steps associated
with dpqp. For 2, protonation can only take place on
the central (phenazine) portion of dppz, and electronic
repulsion makes a second protonation on the same ring
unfavorable, although it may be possible under highly
acidic conditions.41 Multiple protonation steps on the
noncoordinated nitrogen atoms of azaaromatic ligands in
acidic media have been reported for [Ru(bpz)3]2þ (bpz=2,20-
bipyrazine) and [Ru(bpm)3]2þ (bpm=2,20-bipyrimidine).41,42
![求高手翻译英文文献 嗯 关于DNA](/uploads/image/z/16562051-35-1.jpg?t=%E6%B1%82%E9%AB%98%E6%89%8B%E7%BF%BB%E8%AF%91%E8%8B%B1%E6%96%87%E6%96%87%E7%8C%AE+%E5%97%AF+%E5%85%B3%E4%BA%8EDNA)
3的电子吸收谱随着溶液的酸性而变,这揭示了两种可逆质子化步骤的存在(支持信息中的图S1).如支持信息中图S1a示出的那样,当H2SO4的量从0.2%增加到24.4%时,bpy基LC跃迁的强度稍稍下降,而dpqp的ππ*带红移,强度增加,同时在361nm处产生等吸收点.H2SO4从24.2%进一步增加到64.6%会导致3的吸收谱出现新的特点,伴随着在395nm处新的等吸收点(支持信息中的图S1b).相反,对于2来说直到73.4%的H2SO4也只在365nm处观察到一个等吸收点(支持信息中的图S2),对于络合物的MLCT带没有明显的改变.应该指出,1的吸收谱在类似的实验条件下,不随pH值而变,与以前的报行相一致40.3从达到64.4%的H2SO4时的完全恢复可以通过添加NaOH来达到,表明了此络合物在酸性溶液中引人注目的稳定性.
LC dpqp带随着H2SO4的增加从365nm红移到417nm可以解释为dpqp π*轨行在质子化时稳定化的结果,就如关于其他含氮芳杂环配体的报行一样41.据预料,此稳定化使质子化的dpqp配体较易还原,从而也可预期在Ru→dpqp MLCT跃迁中的红移.虽然3的质子化的位置不能确定,但很明显,与dpqp相关的有两个质子化步骤.对于2来说,质子化只能发生在dpqp的中心(吩嗪)位置,电子斥力使得同一环上的二次质子化不顺利,尽管在高酸性条件下这是可能的41.在酸性媒质中的含氮芳杂环配体的非配位原子上多重的质子化步骤对于[Ru(bpz)3]2+ (bpz=2,2’-二吡嗪) 和[Ru(bpm)3]2+ (bpm=2,2’-二嘧啶)已有报道41,42.
LC dpqp带随着H2SO4的增加从365nm红移到417nm可以解释为dpqp π*轨行在质子化时稳定化的结果,就如关于其他含氮芳杂环配体的报行一样41.据预料,此稳定化使质子化的dpqp配体较易还原,从而也可预期在Ru→dpqp MLCT跃迁中的红移.虽然3的质子化的位置不能确定,但很明显,与dpqp相关的有两个质子化步骤.对于2来说,质子化只能发生在dpqp的中心(吩嗪)位置,电子斥力使得同一环上的二次质子化不顺利,尽管在高酸性条件下这是可能的41.在酸性媒质中的含氮芳杂环配体的非配位原子上多重的质子化步骤对于[Ru(bpz)3]2+ (bpz=2,2’-二吡嗪) 和[Ru(bpm)3]2+ (bpm=2,2’-二嘧啶)已有报道41,42.