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991.
Yong-Yi Zeng Prof. Dr. Lan Liu Dr. Bi-Shuang Chen Prof. Dr. Wuyuan Zhang 《ChemistryOpen》2021,10(5):553-559
Photodecarboxylase from Chlorella variabillis (CvFAP) is one of the three known light-activated enzymes that catalyzes the decarboxylation of fatty acids into the corresponding C1-shortened alkanes. Although the substrate scope of CvFAP has been altered by protein engineering and decoy molecules, it is still limited to mono-fatty acids. Our studies demonstrate for the first time that long chain dicarboxylic acids can be converted by CvFAP. Notably, the conversion of dicarboxylic acids to alkanes still represents a chemically very challenging reaction. Herein, the light-driven enzymatic decarboxylation of dicarboxylic acids to the corresponding (C2-shortened) alkanes using CvFAP is described. A series of dicarboxylic acids is decarboxylated into alkanes in good yields by means of this approach, even for the preparative scales. Reaction pathway studies show that mono-fatty acids are formed as the intermediate products before the final release of C2-shortened alkanes. In addition, the thermostability, storage stability, and recyclability of CvFAP for decarboxylation of dicarboxylic acids are well evaluated. These results represent an advancement over the current state-of-the-art. 相似文献
992.
Mathematical Programming - Stochastic dual dynamic programming is a cutting plane type algorithm for multi-stage stochastic optimization originated about 30 years ago. In spite of its popularity in... 相似文献
993.
在 EAST 等离子体垂直位移快速控制电源(快控电源)的数字信号处理(DSP)执行控制程序远程升级中,
通过改变“二次引导”的顺序结构,提出一种新的“二次引导”结构。该结构不需要汇编语言的参与,使用 C
语言编写“二次引导”程序,同时将该结构与无线网络传输技术相结合,实现了对程序的远程升级固化。实验结果
表明,所提出的结合无线网络的“二次引导”结构能够实现对控制电源 DSP 程序的远程加密升级。 相似文献
994.
Computational Optimization and Applications - Our main goal in this paper is to show that one can skip gradient computations for gradient descent type methods applied to certain structured convex... 相似文献
995.
Designs, Codes and Cryptography - A cyclic $$(n,d,w)_q$$ code is a cyclic q-ary code of length n, constant weight w and Hamming distance at least d. The function $$CA_{q}(n,d,w)$$ denotes the... 相似文献
996.
Yu Chen Guang-Yi Zhang Chan Guo Dr. Ping Lan Prof. Dr. Martin G. Banwell Dr. Yu-Tao He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(16):e202104627
The silver-promoted reaction of tertiary cyclobutanols with N-methoxypyridinium salts enables the efficient synthesis of a range of C2-substituted pyridines. The overall process likely occurs by ring-opening (via β-scission) of the cyclobutoxy radical to generate the corresponding γ-keto alkyl radical that itself adds to the pyridinium salt. A wide range of tertiary cyclobutanols and N-methoxypyridinium salts are compatible with the reaction conditions. 相似文献
997.
Dr. Lubna Ghani Dr. Seonghoon Kim Dr. Haoqing Wang Hyun Sung Lee Dr. Jonas S. Mortensen Dr. Satoshi Katsube Dr. Yang Du Dr. Aiman Sadaf Dr. Waqar Ahmed Prof. Bernadette Byrne Prof. Lan Guan Prof. Claus J. Loland Prof. Brian K. Kobilka Prof. Wonpil Im Prof. Pil Seok Chae 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(21):e202200116
Membrane proteins are of biological and pharmaceutical significance. However, their structural study is extremely challenging mainly due to the fact that only a small number of chemical tools are suitable for stabilizing membrane proteins in solution. Detergents are widely used in membrane protein study, but conventional detergents are generally poor at stabilizing challenging membrane proteins such as G protein-coupled receptors and protein complexes. In the current study, we prepared tandem triazine-based maltosides (TZMs) with two amphiphilic triazine units connected by different diamine linkers, hydrazine (TZM−Hs) and 1,2-ethylenediamine (TZM−Es). These TZMs were consistently superior to a gold standard detergent (DDM) in terms of stabilizing a few membrane proteins. In addition, the TZM−Es containing a long linker showed more general protein stabilization efficacy with multiple membrane proteins than the TZM−Hs containing a short linker. This result indicates that introduction of the flexible1,2-ethylenediamine linker between two rigid triazine rings enables the TZM−Es to fold into favourable conformations in order to promote membrane protein stability. The novel concept of detergent foldability introduced in the current study has potential in rational detergent design and membrane protein applications. 相似文献
998.
Herein, the concept of “inverted” (the mode “molecules mainly interact with cations”) deep eutectic solvents (DESs) is proposed. A strategy to form inverted DESs by host‐guest interactions was developed, and thus numerous DESs could be designed and formed by a combination of host and guest molecules. These liquids are expected to be used as nonaqueous electrolytes in potassium‐ion batteries or other fields for further exploration. 相似文献
999.
Jia-Ni Lu Dr. Jiang Liu Long-Zhang Dong Prof. Shun-Li Li Prof. Yu-He Kan Prof. Ya-Qian Lan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(69):15830-15836
The energy crisis and environmental pollution have forced scientists to explore alternative energy conversion and storage devices. The anodic reactions of these devices are all oxygen evolution reactions (OER), so the development of efficient OER electrocatalysts is of great significance. At the same time, understanding the reaction mechanism of OER is conducive to the rational design of efficient OER electrocatalysts. In general, catalytic active centers play a direct role in OER performance. In this paper, a series of stable bimetallic metal–organic frameworks (MOFs, named as Fe3-Con-X2, n=2, 3 and X=F, Cl, Br) with similar structure were synthesized by changing the halogen coordinated with the cobalt metal active center, aiming to investigate the influence of halogen substitution effect on OER performance. It was found that the OER activity of Fe3-Co3-F2 is much better than Fe3-Co2-Cl2 and Fe3-Co2-Br2, indicating that the regulation of the electronegativity change of the coordination halogen atom can regulate the coordination electron structure of the metal active center, thereby achieving effective regulation of OER performance. 相似文献
1000.
Xian Li Wu Shijie Song Xiao Hu Lan Li Sufang 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(12):2535-2541
Russian Journal of Physical Chemistry A - Two type of hollow graphene microspheres were investigated for the adsorption performance of gaseous formaldehyde. Hollow gently reduced graphene oxide... 相似文献