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1.
染料敏化纳米薄膜太阳电池中DMPII浓度的优化   总被引:5,自引:0,他引:5  
利用超微铂电极和循环伏安法及电化学阻抗谱研究了在1,2-二甲基-3-丙基咪唑碘(DMPII)的3-甲氧基丙腈(MePN)溶液中I3和I的氧化还原行为,并对比了由不同浓度的I2和DMPII组成的电解质溶液,其染料敏化纳米薄膜太阳电池(DSCs)的光伏性能. 发现以MePN为溶剂,含1.0 mol•dm-3 DMPII、0.12 mol•dm-3 I2、0.10 mol•dm-3 LiI和0.50 mol•dm-3 4-叔丁基吡啶的电解质溶液,其DSCs的短路光电流密度为16.67 mA•cm-3、开路电压为0.69 V、填充因子为0.70、光电转换效率达8.08%.  相似文献   

2.
合成了3种离子对配合物 [1-benzyl-3-bromopyridium]+[Ni(mnt)2]- (1),[1-(4′-flurobenzyl)-3-bromopyridiunm]+[Ni(mnt)2]- (2),[1-(4′-cholorobenzyl)-3-bromopyridium]+[Ni(mnt)2]- (3),(mnt=马来二腈基二硫烯,maleonitrile dithiolate)获得了单晶并解析了它们的单晶结构。  相似文献   

3.
采用缓慢挥发溶剂的方法合成了硫原子桥联芳基取代四硫富瓦烯(Ar-S-TTF)与碘的3种电荷转移复合物(1)(I3)·I2、(2)(I5)·I2和(32+)(I32,采用单晶X射线衍射、紫外可见光谱、循环伏安对其进行了表征。复合物(1)(I3)·I2C2/c空间群,1呈椅式构型。化合物1与碘之间在溶液中和复合物中电荷转移一致。复合物(2)(I5)·I2P1空间群,2呈椅式构型。复合物(32+)(I32Pbca空间群,32+呈独特的平面构型。化合物23与碘之间在溶液中和复合物中呈现不同的电荷转移。复合物中聚碘阴离子呈现不同的堆积结构:由I3-或I5-/I2组成的一维链状和I3-/I2组成的二维网格状。  相似文献   

4.
利用激光闪光光解技术研究了液相二甲基硫(DMS)与OH, NO3和SO4•-自由基的微观反应机理. 实验结果表明: 在pH 5~9时, OH氧化DMS生成DMSOH, DMSOH会与DMS反应生成(DMS)2+; 而NO3和SO4•-;会直接氧化DMS生成DMS, 生成的DMS会与DMS反应生成(DMS)2+.(DMS)2+与氧气的反应很慢, 它的衰减受pH影响较大.  相似文献   

5.
利用介孔SBA-15作为支架材料制备了一类准固态电解质。离子电导测试表明SBA-15的引入增加了准固态电解质的电导率。通过拉曼光谱证实了聚碘离子I3-和I5 -的存在,并且通过计算表明聚碘离子的扩散系数是I-的两倍。经过组装优化,基于该准固态电解质的电池在AM1.5,75 mW cm-2的光强下可得到4.3%的光电转化效率。  相似文献   

6.
采用高效液相色谱研究了新型铂类抗癌药草酸铂与Cl-的取代反应动力学,并讨论了酸性条件下H+对取代反应的影响。结果表明,Cl-大量存在时,体系中草酸铂与Cl-的取代反应为优势反应,反应对草酸铂和Cl-均为一级。根据动力学数据提出了可能的反应机理,并由此推导出反应速率r=(KClk5′+K1′k3)[L-OHP][Cl-],与实验结果相吻合;当H+也大量存在时,取代反应被加速,此时表观速率常数kobs与[H+]、[Cl-]之间呈非线性递增,但反应对草酸铂仍为一级。在生理盐水中,反应的准一级速率常数kobs=3.6×10-4min-1,1%~2%的草酸铂发生反应所需时间不足1h,因此临床使用草酸铂时要避免与Cl-配伍。  相似文献   

7.
通过无机碘盐(MIn)与 cis-[Fe(CO)4I2]反应制备了 5 个盐类化合物 fac-M[Fe(CO)3I3]n (Mn+=Na+ (1),K+ (2),Mg2+ (3),Ca2+ (4),NH4+ (5)),探讨了阳离子Mn+fac-[Fe(CO)3I3]-阴离子的稳定性和细胞毒性的影响。通过傅里叶变换红外光谱(FTIR)监测,发现盐 1~5在 DMSO、D2O、生理盐水等介质中均能缓释 CO,其释放动力学符合一级反应动力学模型;还发现溶液中碘离子的浓度和酸度对该阴离子的缓释CO性能也具有调节作用。通过噻唑蓝(MTT)实验评估了盐1~5对膀胱癌细胞的毒性,其24 h半抑制浓度(IC50)在 25~43 μmol·L-1。与有机铵阳离子类的盐化合物相比,盐1~5在含水介质中的释放 CO速率下降,毒性亦有下调。研究还发现这类fac-[Fe(CO)3I3]-阴离子在缓释CO的同时释放碘自由基,并能导致线粒体活性氧(ROS)水平、Parkin蛋白表达均上调。铁死亡抑制剂(Ferrostatin-1和Liproxstatin-1)试验结果表明这类化合物可能引发铁死亡通路并促进肿瘤细胞死亡。  相似文献   

8.
通过无机碘盐(MIn)与cis-[Fe (CO)4I2]反应制备了5个盐类化合物fac-M[Fe (CO)3I3]n(Mn+=Na+(1),K+(2),Mg2+(3),Ca2+(4),NH4+(5)),探讨了阳离子Mn+fac-[Fe (CO)3I3]-阴离子的稳定性和细胞毒性的影响。通过傅里叶变换红外光谱(FTIR)监测,发现盐1~5在DMSO、D2O、生理盐水等介质中均能缓释CO,其释放动力学符合一级反应动力学模型;还发现溶液中碘离子的浓度和酸度对该阴离子的缓释CO性能也具有调节作用。通过噻唑蓝(MTT)实验评估了盐1~5对膀胱癌细胞的毒性,其24 h半抑制浓度(IC50)在25~43 μmol·L-1。与有机铵阳离子类的盐化合物相比,盐1~5在含水介质中的释放CO速率下降,毒性亦有下调。研究还发现这类fac-[Fe (CO)3I3]-阴离子在缓释CO的同时释放碘自由基,并能导致线粒体活性氧(ROS)水平、Parkin蛋白表达均上调。铁死亡抑制剂(Ferrostatin-1和Liproxstatin-1)试验结果表明这类化合物可能引发铁死亡通路并促进肿瘤细胞死亡。  相似文献   

9.
trans-[XRu(py)4(NO)]2+(X=Cl,Br)与等物质的量的NaN3在甲醇中反应后生成中间体trans-[XRu(py)4(CH3OH)]+,它再与过量的Na[N(CN)2]或K[C(CN)3]反应后生成单核配合物trans-XRu(py)3L(X=Cl,Br,L=N(CN)2-,C(CN)3-)。单核配合物XRu(py)4L与[X′Ru(py)4(CH3OH)]+进行分子组装,生成了一系列双核钌配合物trans-[X(py)4Ru(μ-L)Ru(py)4X′]+。用等物质的量的NOBF4或(NH4)2[Ce(NO3)6]氧化这些RuRu双核钌配合物,得到了一系列RuRu混合价配合物trans-[X(py)4Ru(μ-L)Ru(py)4X′]2+。N(CN)2-桥联的RuRu混合价配合物在近红外区存在中等强度的吸收,起源于混合价态间的电荷跃迁(Intervalence Charge Transfer,简称为IVCT),且其最大吸收波长随着溶剂极性的改变而发生变化,它们属于Class Ⅱ类型的混合价化合物;而C(CN)3-桥联的RuRu混合价配合物在近红外的吸收要强得多,且溶剂极性的改变对IVCT最大吸收波长基本无影响,它们属于介于价态定域与离域之间的混合价配合物。  相似文献   

10.
在超声分子束条件下,利用360.50 nm的电离激光使N2O分子经由[3+1]共振增强多光子电离(REMPI)产生纯净的N2O+(X2Π(000))分子离子,用另一束解离激光在230-275 nm范围扫描获得N2O+经由B2Пi←X2Π跃迁产生的光解碎片(NO+和N2+)激发(PHOFEX)谱. 获得的光解碎片激发谱可以归属为B2Пi(00n)←X2Π(000)序列跃迁. 我们分别将线性三原子分子离子N2O+中N―N伸缩振动简化成NO和N之间的简谐振动,N―O伸缩振动简化成N2和O之间的简谐振动,用谐振子的简谐势能曲线和波函数对N2O+分子离子X2Π和B2Пi电子态振动能级间跃迁的Franck-Condon因子进行计算,和实验得到的碎片离子增强谱实验强度进行比较,对前人给出的分子数据(分子平衡核间距)进行验证,讨论了N2O+经由B2Пi(00n)←X2Π(000)电子态跃迁的光解离机理和碎片离子的分支比.  相似文献   

11.
Two new highly selective triiodide electrodes have been prepared using charge‐transfer complex of iodine with cryptand 222 as an electroactive ionophore and nitrophenyl octyl ether as a plasticizing agent. The electrodes showed Nernstian response to triiodide ions over a concentration range from 1.0 × 10?;2 — 7.9 × 10?;7 M and from 1.0 × 10?;2 — 1 × 10?;6 M with detection limits of 6.3 × 10?;7 and 7.9 × 10?;7 M for cryptand and its charge‐transfer complex with iodine, respectively. The response times (t95%) of the sensors were 10 and 5 s. The membrane could be used for more than 1 month without any divergence in potentials. The proposed sensors exhibited very high selectivity for triiodide ion over other anions, and could be used in a wide pH range ?2–10. These electrodes were successfully applied as an indicator electrode in potentiometric titration of copper in ore samples.  相似文献   

12.
Fullerence C60‐cryptand 22 was prepared and successfully applied as the electric carrier in the PVC electrode membrane of a bifunctional ion‐selective electrode for cations, e.g., Ag+ ions as well as anions, e.g., I? ions. The bifunctional ion‐selective electrode based on C60‐cryptand 22 can be applied as a Silver (Ag+) ion selective electrode with an internal electrode solution of 10?3 M AgNO3 in water (pH = 6.3), or as an Iodide (I?) ion selective electrode with an acidic internal electrode solution of 10?4 M KI(aq) (pH = 2) in which the cryptand 22 is protonated, and the C60‐cryptand 22 is changed to C60‐Cryptand22–H+ and becomes an anionic electro‐carrier to absorb the I? ion. The Ag+ ion selective electrode based on C60‐cryptand 22 gave a linear response with a near‐Nernstian slope (59.5 mV decade?1) within the concentration range 10?1‐10?3 M Ag+(aq). The Ag+ ion electrode exhibited comparatively good selectivity for silver ions, over other transition‐metal ions, alkali and alkaline earth metal ions. The Ag+ ion selective electrode with good stability and reproducibility was successfully used for the titration of Ag+(aq) with Cl? ions. The Iodide (I?) Ion selective electrode based on protonated C60–cryptand22‐H+ also showed a linear response with a nearly Nernstian slope (58.5 mV decade?1) within 10?1 ‐ 10?3 M I? (aq) and exhibited good selectivity for I? ions and had small selectivity coefficients (10?2–10?3) for most of other anions, e.g., F? , OH?, CH3COO?, SO42?, CO32?, CrO42?, Cr2O72? and PO43? ions.  相似文献   

13.
N‐Boc/Fmoc/Z‐N′‐formyl‐gem‐diaminoalkyl derivatives, intermediates particularly useful in the synthesis of partially modified retro‐inverso peptides, have been characterized by both positive and negative ion electrospray ionization (ESI) ion‐trap multi‐stage mass spectrometry (MSn). The MS2 collision induced dissociation (CID) spectra of the sodium adduct of the formamides derived from the corresponding N‐Fmoc/Z‐amino acids, dipeptide and tripeptide acids show the [M + Na‐NH2CHO]+ ion, arising from the loss of formamide, as the base peak. Differently, the MS2 CID spectra of [M + Na]+ ion of all the N‐Boc derivatives yield the abundant [M + Na‐C4H8]+ and [M + Na‐Boc + H]+ ions because of the loss of isobutylene and CO2 from the Boc protecting function. Useful information on the type of amino acids and their sequence in the N‐protected dipeptidyl and tripeptidyl‐N′‐formamides is provided by MS2 and subsequent MSn experiments on the respective precursor ions. The negative ion ESI mass spectra of these oligomers show, in addition to [M‐H]?, [M + HCOO]? and [M + Cl]? ions, the presence of in‐source CID fragment ions deriving from the involvement of the N‐protecting group. Furthermore, MSn spectra of [M + Cl]? ion of N‐protected dipeptide and tripeptide derivatives show characteristic fragmentations that are useful for determining the nature of the C‐terminal gem‐diamino residue. The present paper represents an initial attempt to study the ESI‐MS behavior of these important intermediates and lays the groundwork for structural‐based studies on more complex partially modified retro‐inverso peptides. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

14.
A good understanding of gas‐phase fragmentation chemistry of peptides is important for accurate protein identification. Additional product ions obtained by sodiated peptides can provide useful sequence information supplementary to protonated peptides and improve protein identification. In this work, we first demonstrate that the sodiated a3 ions are abundant in the tandem mass spectra of sodium‐cationized peptides although observations of a3 ions have rarely been reported in protonated peptides. Quantum chemical calculations combined with tandem mass spectrometry are used to investigate this phenomenon by using a model tetrapeptide GGAG. Our results reveal that the most stable [a3 + Na ? H]+ ion is present as a bidentate linear structure in which the sodium cation coordinates to the two backbone carbonyl oxygen atoms. Due to structural inflexibility, further fragmentation of the [a3 + Na ? H]+ ion needs to overcome several relatively high energetic barriers to form [b2 + Na ? H]+ ion with a diketopiperazine structure. As a result, low abundance of [b2 + Na ? H]+ ion is detected at relatively high collision energy. In addition, our computational data also indicate that the common oxazolone pathway to generate [b2 + Na ? H]+ from the [a3 + Na ? H]+ ion is unlikely. The present work provides a mechanistic insight into how a sodium ion affects the fragmentation behaviors of peptides. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

15.
Reactions between potassium tetraiodidoaurate(III) and pyridine (py, C5H5N) or 3,4‐lutidine (3,4‐dimethylpyridine, 3,4‐lut, C7H9N) were tested as possible sources of azaaromatic complexes of gold(III) iodide, but all identifiable products contained gold(I). The previously known structure dipyridinegold(I) diiodidoaurate(I), [Au(py)2]+·[AuI2], ( 3 ) [Adams et al. (1982). Z. Anorg. Allg. Chem. 485 , 81–91], was redetermined at 100 K. The reactions with 3,4‐lutidine gave three different types of crystal in small quantities. 3,4‐Dimethylpyridine–3,4‐dimethylpyridinium diiodidoaurate(I), [(3,4‐lut)2H]+·[AuI2], ( 1 ), consists of an [AuI2] anion on a general position and two [(3,4‐lut)2H]+ cations across twofold axes. Bis(3,4‐dimethylpyridine–3,4‐dimethylpyridinium) diiodidoaurate(I) iodide, [(3,4‐lut)2H+]2·[AuI2]·I, ( 2 ), crystallizes as two polymorphs, each forming pseudosymmetric inversion twins, in the space groups P21 and Pc (but resembling P21/m and P2/c), respectively. These are essentially identical layer structures differing only in their stacking patterns and thus might be regarded as polytypes.  相似文献   

16.
Single crystals of (1,3‐diamino‐5‐azaniumyl‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)lithium(I) diiodide dihydrate, [Li(C6H16N3O3)(C6H15N3O3)]I2·2H2O or [Li(Htaci)(taci)]I2·2H2O (taci is 1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol), (I), bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)sodium(I) iodide, [Na(C6H15N3O3)2]I or [Na(taci)2]I, (II), and bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)potassium(I) iodide, [K(C6H15N3O3)2]I or [K(taci)2]I, (III), were grown by diffusion of MeOH into aqueous solutions of the complexes. The structures of the Na and K complexes are isotypic. In all three complexes, the taci ligands adopt a chair conformation with axial hydroxy groups, and the metal cations exhibit exclusive O‐atom coordination. The six O atoms of the resulting MO6 unit define a centrosymmetric trigonal antiprism with approximate D3d symmetry. The interligand O...O distances increase significantly in the order Li < Na < K. The structure of (I) exhibits a complex three‐dimensional network of R—NH2—H...NH2R, R—O—H...NH2R and R—O—H...O(H)—H...NH2R hydrogen bonds. The structures of the Na and K complexes consist of a stack of layers, in which each taci ligand is bonded to three neighbours via pairwise O—H...NH2 interactions between vicinal HO—CH—CH—NH2 groups.  相似文献   

17.
In this contribution we investigated the ion complexation of Bühl's cryptand, dodeka(ethylene)octamine by quantum chemical methods (B3LYP/LANL2DZp). This cryptand is an isomer of a well‐known Lehn‐type cryptand [TriPip222]. The ion selectivity was determined based on the energetic criteria derived by model reactions starting from solvated metal ions and empty dodeka(ethylene)octamine, and by comparing the M–N bond length in [M ? dodeka(ethylene)octamine]m+ and [M(NH3)6]m+. We calculated that Bühl's cryptand will complex best Na+ followed by Li+ as alkaline cations and Ca2+ followed by Mg2+ as alkaline earth metal ions. Based on this data we conclude that Bühl's cryptand offers a smaller cavity to nest ions than the Lehn‐type [TriPip222].  相似文献   

18.
The accessibility of triads with deltahedral Zintl clusters in analogy to fullerene–linker–fullerene triads is another example for the close relationship between fullerenes and Zintl clusters. The compound {[K(2.2.2‐crypt)]4[RGe9‐CH?CH? CH?CH‐Ge9R]}(toluene)2 (R=(2Z,4E)‐7‐amino‐5‐aza‐hepta‐2,4‐dien‐2‐yl), containing two deltahedral [Ge9] clusters linked by a conjugated (1Z,3Z)‐buta‐1,3‐dien‐1,4‐diyl bridge, was synthesized through the reaction of 1,4‐bis(trimethylsilyl)butadiyne with K4Ge9 in ethylenediamine and crystallized after the addition of 2.2.2‐cryptand and toluene. The compound was characterized by single‐crystal structure analysis as well asNMR and IR spectroscopy.  相似文献   

19.
We have investigated gas‐phase fragmentation reactions of protonated benzofuran neolignans (BNs) and dihydrobenzofuran neolignans (DBNs) by accurate‐mass electrospray ionization tandem and multiple‐stage (MSn) mass spectrometry combined with thermochemical data estimated by Computational Chemistry. Most of the protonated compounds fragment into product ions B ([M + H–MeOH]+), C ([ B –MeOH]+), D ([ C –CO]+), and E ([ D –CO]+) upon collision‐induced dissociation (CID). However, we identified a series of diagnostic ions and associated them with specific structural features. In the case of compounds displaying an acetoxy group at C‐4, product ion C produces diagnostic ions K ([ C –C2H2O]+), L ([ K –CO]+), and P ([ L –CO]+). Formation of product ions H ([ D –H2O]+) and M ([ H –CO]+) is associated with the hydroxyl group at C‐3 and C‐3′, whereas product ions N ([ D –MeOH]+) and O ([ N –MeOH]+) indicate a methoxyl group at the same positions. Finally, product ions F ([ A –C2H2O]+), Q ([ A –C3H6O2]+), I ([ A –C6H6O]+), and J ([ I –MeOH]+) for DBNs and product ion G ([ B –C2H2O]+) for BNs diagnose a saturated bond between C‐7′ and C‐8′. We used these structure‐fragmentation relationships in combination with deuterium exchange experiments, MSn data, and Computational Chemistry to elucidate the gas‐phase fragmentation pathways of these compounds. These results could help to elucidate DBN and BN metabolites in in vivo and in vitro studies on the basis of electrospray ionization ESI‐CID‐MS/MS data only.  相似文献   

20.
The Cδ?H amination of unactivated, secondary C?H bonds to form a broad range of functionalized pyrrolidines has been developed by a triiodide (I3?)‐mediated strategy. By in situ 1) oxidation of sodium iodide and 2) sequestration of the transiently generated iodine (I2) as I3?, this approach precludes undesired I2‐mediated decomposition which can otherwise limit synthetic utility to only weak C(sp3)?H bonds. The mechanism of this triiodide‐mediated cyclization of unbiased, secondary C(sp3)?H bonds, by either thermal or photolytic initiation, is supported by NMR and UV/Vis data, as well as intercepted intermediates.  相似文献   

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