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361.
Jun‐Ho Yum Dr. Daniel P. Hagberg Soo‐Jin Moon Karl Martin Karlsson Tannia Marinado Licheng Sun Prof. Anders Hagfeldt Prof. Mohammad K. Nazeeruddin Dr. Michael Grätzel Prof. 《Angewandte Chemie (International ed. in English)》2009,48(9):1576-1580
Finely tuned : A stable dye‐sensitized solar cell that contains a molecularly engineered organic dye has been prepared. The efficiency of the cell remains at 90 % after 1000 h of light soaking at 60 °C. The remarkable stability of the cell is also reflected in the open‐circuit voltage value (Voc), short‐circuit photocurrent‐density value (Jsc), and the fill factor, which also show barely no decline (see picture).
362.
Rui Zhao Pan Shi Ji-bin Cui Chaowei Shi Xiao-Xiong Wei Jie Luo Zhemin Xia Wei-Wei Shi Yingxin Zhou Jiahui Tang Changlin Tian Mark Meininghaus Donald Bierer Jing Shi Yi-Ming Li Lei Liu 《Angewandte Chemie (International ed. in English)》2023,62(6):e202216365
Chemical synthesis of insulin superfamily proteins (ISPs) has recently been widely studied to develop next-generation drugs. Separate synthesis of multiple peptide fragments and tedious chain-to-chain folding are usually encountered in these studies, limiting accessibility to ISP derivatives. Here we report the finding that insulin superfamily proteins (e.g. H2 relaxin, insulin itself, and H3 relaxin) incorporating a pre-made diaminodiacid bridge at A-B chain terminal disulfide can be easily and rapidly synthesized by a single-shot automated solid-phase synthesis and expedient one-step folding. Our new H2 relaxin analogues exhibit almost identical structures and activities when compared to their natural counterparts. This new synthetic strategy will expediate production of new ISP analogues for pharmaceutical studies. 相似文献
363.
Photochemical activation by triplet photosensitizers is highly expedient for a green focus society. In this work, we have theoretically probed excited state characteristics of thioxanthone and its derivatives for their triplet harvesting efficiency using density functional theory (DFT) and time-dependent density functional theory (TDDFT). Absorption and triplet energies corroborate well with the available experimental data. Our results predict that both the S1 and T1 states are π-π* in nature, which renders a high oscillator strength for S0 to S1 transition. Major triplet exciton conversion occurs through intersystem crossing (ISC) channel between the S1 (1π-π*) and high energy 3n- π* state. Apart from that, there is both radiative and non-radiative channel from S1 to S0, which competes with the ISC channel and reduces the triplet harvesting efficiency. For thioxanthones with −OMe (Me=Methyl) or −F substitution at 2 or 2’ positions, the ISC channel is not energetically feasible, causing sluggish intersystem crossing quantum yield (ΦISC). For unsubstituted thioxanthone and for isopropyl substitution at 2’ position, the S1-T1 gap is slightly positive ( ), rendering a lower triplet harvesting efficiency. For systems with −OMe or −F substitution at 3 or 3’ position of thioxanthone, because of buried π state and high energy π* state, the S1-3nπ* gap becomes negative. This leads to a high ΦISC (>0.9), which is key to being an effective photocatalyst. 相似文献