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21.
张小梅  李淼淼  王琪  江宇  耿延候 《应用化学》2019,36(9):1023-1034
以不同烷基取代的二噻吩并吡咯(DTP)为π桥,连接吲哒省并二噻吩(IDT)中间单元和氰基茚酮(IC)或二氟代氰基茚酮(2F-IC)末端基团,设计并合成了6个窄带隙的非富勒烯受体材料。 其中,IDTDTP-C2C2-H和IDTDTP-C2C2-F中的DTP单元以1-乙基丙基为侧链,IDTDTP-C6C6-H和IDTDTP-C6C6-F中的DTP单元以1-己基庚基为侧链,IDTDTP-C12-H和IDTDTP-C12-F中的DTP单元以十二烷基为侧链。 6个分子均具有较窄的光学带隙(1.37~1.44 eV)。 相比于以IC为末端基团的分子(IDTDTP-C2C2-H、IDTDTP-C6C6-H和IDTDTP-C12-H),由于氟原子的拉电子效应,以2F-IC为末端基团的分子(IDTDTP-C2C2-F、IDTDTP-C6C6-F和IDTDTP-C12-F)具有红移的吸收光谱,以及更低的最高分子占有轨道能级(HOMO)和最低分子空轨道(LUMO)能级。 以宽带隙聚合物聚[2,6-(4,8-双(5-(2-乙基己基))噻吩-2-基)-苯并[1,2-b:4,5-b']二噻吩-alt-5,5-(1',3'-二-2-噻吩)-5',7'-双(2-乙基己基)-苯并[1',2'-c:4',5'-c']二噻吩-4,8-二酮](PBDB-T)为给体材料,制备了有机太阳能电池器件。 PBDB-T:IDTDTP-C6C6-F共混薄膜具有较高且更平衡的空穴/电子迁移率,以及良好的形貌,基于PBDB-T:IDTDTP-C6C6-F的有机太阳能电池获得了6.94%的能量转换效率,开路电压为0.86 V,短路电流密度为13.56 mA/cm2,填充因子为59.5%。  相似文献   
22.
Let V be the variety generated by two-element distributive lattice B2 and k prime fields Fp1,...,Fpk. That is to say that V = HSP{B2, Fp1,...,Fpk}. It is proved that the variety V is finitely based. Also, the two-element distributive lattice B2 and prime fields Fp1,..., Fpk are, up to isomorphism, the only subdirectly irreducible semirings in V. Some known results are extended and enriched.  相似文献   
23.
Aiming highly efficient conversion of greenhouse gas CO2 to cyclic carbonates, a biomass Ru(III) Schiff base complex catalyst ( SalRu ) was constructed by employing a derivative of Lignin degradation (5-aldehyde vanillin). The SalRu catalyst had a remarkable conversion for epoxides into corresponding cyclic carbonates even at atmospheric pressure of CO2 without the presence of co-catalyst. As the condition at 120 °C and 2 MPa CO2 the conversion reached to 94 % with selectivity at 99 % after 8 h. 32 % cyclic carbonate production was obtained even under 0.2 MPa CO2 pressure. The epoxide activation and ring opening, CO2 insertion and cyclic carbonate formation were illuminated explicitly through the of characteristic absorption peaks changing, which further providing direct and visual evidence for the mechanism proposing. This study has important theoretical significance for the comprehensive utilization of environmental pollutants and energy.  相似文献   
24.
Ligand-protected gold clusters are widely used in biosensors and catalysis. Understanding the structural evolution of these kinds of nanoclusters is important for experimental synthesis. Herein, based on the particle swarm optimisation algorithm and density functional theory method, we use [Au1(SH)2]n, [Au2(SH)3]n, [Au3(SH)4]n (n?=?1–3) as basic units to research the structural evolution relationships from building blocks to the final whole structures. Results show that there is a ‘line-ring-core’ structural evolution pattern in the growth process of the nanoclusters. The core structures of the ligand-protected gold clusters consist of Au3, Au4, Au6 and Au7 atoms. The electronics and optics analysis reflects that stability and optical properties gradually enhance with increase in size. These results can be used to understand the initial growth stage and design new ligand-protected nanoclusters.  相似文献   
25.
Aqueous rechargeable zinc-iodine batteries(ZIBs)emerging as a promising energy storage alternative have attracted con-siderable attention.However,ZIBs still suf...  相似文献   
26.
Due to the increasingly depleted limited fossil fuel resources, the development of renewable energy is the key to promote sustainable development which is an im...  相似文献   
27.
以硝酸铈铵为引发剂, 在自制的中空介孔二氧化硅(HMS)的空腔和通道内引发丙烯腈自由基聚合, 并将其氰基偕胺肟化, 用于制备具有吸附Cr(Ⅵ)的廉价有机无机复合吸附材料—中空介孔二氧化硅锚固聚偕胺肟. 通过傅里叶变换红外光谱(FTIR)、 扫描电子显微镜(SEM)及N2吸附-脱附比表面分析对中空介孔二氧化硅锚固聚偕胺肟进行表征. 结果表明, 制备的中空微球直径约为400 nm, 其壁上孔径约为11.0 nm, 比表面积约为431 m2/g, 锚固聚偕胺肟后中空微球壁上孔道直径约为4.6 nm, 比表面积降低为347 m2/g. HMS锚固的聚偕胺肟对重铬酸钾溶液中铬的吸附量高达0.46 mmol/g, 吸附过程中伴随化学反应, 符合伪二级动力学模型, 可用作废水处理中重金属离子的高效廉价吸附材料.  相似文献   
28.
A resonant-light-scattering (RLS) method was proposed to quantify phosphate for screening inhibitors of isozymes of cyclic nucleotide phosphodiesterase (PDE). In acidified mixtures of phosphate, papaverine and molybdate, there were aggregates exhibiting micrometre sizes, no absorbance peaks over 360 nm but strong RLS peaks at 392 nm; Mie scattering thus accounted for the RLS signals. When papaverine was added before molybdate to acidified samples of phosphate, RLS signals at 392 nm were stable from 5 to 25 min since the addition of molybdate; after optimization, phosphate from 0.40 to 3.60 μM was quantifiable. This RLS method tolerated 60 mg L−1 proteins besides common PDE inhibitors and dimethyl sulfoxide in acidified samples of phosphate; the integration of this RLS method with the coupled action of a phosphomonoesterase on PDE product was thus rational to measure PDE activities without the removal of proteins in samples. By quantifying activities of a truncated mutant of human PDE4B2 via this RLS method, Michaelis–Menten constant, inhibition constants of rolipram, papaverine and theophylline varied over three magnitudes and were consistent with those estimated by an improved malachite green assay of phosphate, respectively. Hence, this novel RLS method was promising for screening inhibitors of PDE isozymes.  相似文献   
29.
本文首次从系统可靠性的角度研究多级适应性延误休假Mx/G(M/G)/1可修排队系统,讨论了服务台如下的一些可靠性问题:(1)在时刻t失效的概率;(2)在服务员忙期内失效的次数;(3)在(0,t]内的平均失效次数;(4)在服务员忙期内的失效时间.  相似文献   
30.
Conjugated microporous polymers (CMPs) have recently received extensive attention in oil/organic solvent-water separation field as a kind of ideal porous absorbents with tunable porosity, large surface areas, and super-hydrophobicity. However, reports on the application of CMPs in adsorption of hydrophilic contaminants from water are very few. In this work, we studied the adsorption of metronidazole (MNZ), a polar antibiotic, by two kinds of CMPs. The adsorption characteristics of MNZ by the CMPs, including adsorption kinetics, mechanism, and isotherm parameters were calculated. The adsorption kinetics of MNZ was well expressed by the pseudo-second-order model, and the adsorption process was found to be mainly controlled by film diffusion. The adsorption isotherm data agreed well with the Langmuir isotherm model, and the values of free energy E indicated that the adsorption nature of MNZ on the CMPs was physisorption. Increasing dispersion degree of the CMPs in MNZ solution resulted in greater adsorption. This work may provide fundamental guidance for the removal of antibiotics by CMPs.  相似文献   
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