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Chinese Chemical Letters 2019年第2期30卷 392-394页

作者： Fusong Zhang Qi Lai xiaodong shi Zhiguang Song Department of Chemistry Jilin University Department of Chemistry University of South Florida

A gold-catalyzed three-component coupling reaction (A3 reaction) was developed as an efficient approach for the synthesis of challenging 2, 4-disubstituted quinoline derivatives. Compared to previously reported Cu/Au bi-catalyst system, this protocol enables achieving A3 reaction only in the presence of triazole-gold catalyst. Notably, 4-alkyl substituted or 2-alkyl substituted quinoline derivatives were obtained with good yields, which highlighted the unique advantage of this new strategy.

关键词： Quinoline Gold catalysis A3 reaction Triazole-gold

Highly Dispersed Cobalt Nanoparticles Embedded in Nitrogen-Doped Graphitized Carbon for Fast and Durable Potassium Storage

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Nano-Micro Letters 2021年第2期13卷 1-12页

作者： xiaodong shi Zhenming Xu Cheng Han Runze shi Xianwen Wu Bingan Lu Jiang Zhou Shuquan Liang School of Materials Science and Engineering Central South UniversityChangsha 410083People’s Republic of China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Harvard John.A.Paulson School of Engineering and Applied Sciences Harvard University29 Oxford StreetCambridgeMA 02138USA School of Chemistry and Chemical Engineering Jishou UniversityJishou 416000People’s Republic of China School of Physics and Electronics State Key Laboratory of Advanced Design and Manufacturing for Vehicle BodyHunan UniversityChangsha 410082People’s Republic of China Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South UniversityChangsha 410083People’s Republic of China

Potassium-ion batteries(KIBs)have great potential for applications in large-scale energy storage ***,the larger radius of K+leads to sluggish kinetics and inferior cycling performance,severely restricting its practical ***,we propose a rational strategy involving a Prussian blue analogue-derived graphitized carbon anode with fast and durable potassium storage capability,which is constructed by encapsulating cobalt nanoparticles in nitrogen-doped graphitized carbon(Co-NC).Both experimental and theoretical results show that N-doping effectively promotes the uniform dispersion of cobalt nanoparticles in the carbon matrix through Co-N ***,the cobalt nanoparticles and strong Co-N bonds synergistically form a threedimensional conductive network,increase the number of adsorption sites,and reduce the diffusion energy barrier,thereby facilitating the adsorption and the diffusion *** multiple effects lead to enhanced reversible capacities of 305 and 208.6 mAh g^−1 after 100 and 300 cycles at 0.05 and 0.1 A g^−1,respectively,demonstrating the applicability of the Co-NC anode for KIBs.

关键词： Cobalt nanoparticles Nitrogen-doped graphitized carbon Co-N bonds Cycling stability Potassium-ion batteries

Application of a neural network system combined with genetic algorithm to rank coalbed methane reservoirs in the order of exploitation priority

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Petroleum Science 2008年第4期5卷 334-339页

作者： Li Weichao Wu xiaodong shi Junfeng Key Laboratory of Petroleum Engineering Ministry of Education China University of Petroleum Beijing 102249 China

A new method based on the combination of a neural network and a genetic algorithm was proposed to rank the order of exploitation priority of coalbed methane reservoirs. The neural network was used to acquire the weights of reservoir parameters through sample training and genetic algorithm was used to optimize the initial connection weights of nerve cells in case the neural network fell into a local minimum. Additionally, subordinate functions of each parameter were established to normalize the actual values of parameters of coalbed methane reservoirs in the range between zero and unity. Eventually, evaluation values of all coalbed methane reservoirs could be obtained by using the comprehensive evaluation method, which is the basis to rank the coalbed methane reservoirs in the order of exploitation priority. The greater the evaluation value, the higher the exploitation priority. The ranking method was verified in this paper by ten exploited coalbed methane reservoirs in China. The evaluation results are in agreement with the actual exploitation cases. The method can ensure the truthfulness and credibility of the weights of parameters and avoid the subjectivity caused by experts. Furthermore, the probability of falling into local minima is reduced, because genetic the algorithm is used to optimize the neural network system.

关键词： Coalbed methane neural network system genetic algorithm evaluation index weight

Integrated Transcriptomics and Metabolomics Analysis for the Mechanism Underlying White-to-Pink Petal Color Transition in Hibiscus mutabilis Flowers

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Phyton-International Journal of Experimental Botany 2024年第10期93卷 2571-2581页

作者： xiaodong shi Tingyu Wang Sui Ai Jiasi Li College of Food and Biological Engineering Chengdu UniversityChengdu610016China

Cotton rose(Hibiscus mutabilis)is a well-known ornamental plant that produces large flowers of vibrant ***,metabolites in *** flowers with vibrant color have not been fully *** performing a combined analysis of metabolomics and transcriptomics data,we here explored mechanisms for the production of primary active compounds in this *** statistics unveiled differences in flavonoid metabolism between white and pink flowers,with pink flowers exhibiting a greater flavonoid *** white-to-pink transition of cotton rose flowers may be attributed to pelargonidin-3-O-glucoside *** examining the expression of genes related to the structure of flavonoids,pink flowers were found to have a higher number of upregulated genes than white flowers,which resulted in higher flavonoid accumulation in the pink *** results underscore the potential applications and development value of cotton rose *** study provides relevant insights into the regulation of key active components and the theoretical basis for the efficient utilization of cotton rose flowers.

关键词： Hibiscus mutabilis transcriptome sequencing metabolites flavonoid gene expression

Curcumin inhibits beta-amyloid protein 40/42 expression in the brain in a concentration-and time-dependent manner

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Neural Regeneration Research 2010年第16期5卷 1205-1210页

作者： Xiong Zhang Lu Si xiaodong shi Wenke Yin Yu Li Institute of Neuroscience Chongqing Medical University Chongqing 400016 China Department of Pathology Chongqing Medical University Chongqing 400016 China

Several studies have demonstrated that the amount of beta-amyloid （Aβ） protein in the brain can be lowered by down-regulating Aβ production, promoting Aβ degradation, reducing Aβ oligomerization or deposition, thereby alleviating symptoms of Alzheimer＇s disease. Curcumin has been known to be a peroxisome proliferator activated receptor gamma （PPARy） agonist and can obviously inhibit Aβ production and oligomerization. This study investigated the effects of curcumin on the G-site APP cleaving enzyme 1 （BACE1） activity and PPARy expression in human neuroblastoma SH-SY5Y cells, and validated the inhibitory effects of curcumin on Aβ40/42 expression in the brain. Results revealed that PPARy mRNA and protein expression in the human neuroblastoma SH-SY5Y cells significantly increased with increasing curcumin concentration and time course （P 〈 0.05）; BACE1 mRNA and protein expression and Aβ40/42 production significantly decreased with increasing curcumin concentration and time course （P 〈 0.05）. The changes in PPARy and BACE1 expression during Aβ production could be reversed by the PPARy antagonist GW9662. These findings indicate that curcumin reduced Aβ production by activating PPARy expression and inhibiting BACE1 expression in a concentration- and time-dependent manner.

关键词： beta-amyloid Alzheimer's disease β-site APP cleaving enzyme 1 curcumin peroxisome proliferator activated receptor gamma

Synthesis and characterization of fluorescence active triazole-gold complexes

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Science China Chemistry 2015年第7期58卷 1235-1238页

作者： Boliang Dong Yijin Su Xiaohan Ye Jeffrey L.Petersen xiaodong shi C.Eugene Bennett Department of Chemistry West Virginia University

Fluorescence active fused-triazole was developed as a ligand in gold(I) cation coordination. The coordination ability was evaluated using NMR and fluorescence emission. Our previously reported N-2-aryl-triazoles, though gave good emission, could not form stable complexes with gold cations. A new N-fused-triazole(NFT) derivative was prepared and the ligand indicated good fluorescence emission, and formed strong coordination with gold cations. Both ligand and complex were characterized by X-ray crystallography. Fluorescence properties of various gold complexes(with different primary ligands) were evaluated, which suggested the feasibility of using fluorescence emission as potential tools for future mechanistic investigation.

关键词： fluorescence catalysis 1 2 3-triazole gold conjugation

A new multi-parallel-beam collimators with improved sensitivity for SPECT

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Nuclear Science and Techniques 2012年第2期23卷 90-96页

作者： MA Jiayi ZHAO Jingwu shi xiaodong ZHANG Kevin HUANG Runshen physics School Nanjing University Nanjing 210093 China New York Institute of Technology New York USA

In this paper, a new design of multi-parallel-beam (MPB) collimators with projection multiplexing is proposed. In the MPB system, two different oblique parallel channels are introduced in a conventional parallel-beam collimator. The sensitivity of the single photon emission computed tomography (SPECT) system is improved by allowing projection overlapping. Comparative simulation studies were performed in the MPB collimators, general purpose parallel-beam (GPPB) collimators and high sensitivity parallel-beam (HSPB) collimators. In the simulation, attenuation, scattering and the impact of detector response were neglected. Simulation results show that the sensitivity is improved for the MPB collimator comparing with parallel-beam collimator. The behavior of spatial resolution is only different near the front face of the collimators and approaches that of the GPPB with increasing depth. Proper pre-filtering is helpful for the image reconstruction in the MPB collimators. Comparing with the HSPB collimator, the MPB can achieve a similar sensitivity and better resolution. The simulation ot the U87 cells, and their expression levels were higher in the 10 Gy group than in the 0 Gy group. The differential gene expression in DCX-U87 cells before and after radiation is helpful for future investigations into the mechanisms of radiation therapy in neurogliocytoma cells.

关键词：高灵敏度准直器显像并行计算机断层空间分辨率准直系统准直仪

Synthesis and characterization of fluorescence active G_(4)-quartet and direct evaluation of self-assembly impact on emission

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Chinese Chemical Letters 2022年第9期33卷 4203-4207页

作者： Ying He Mengjia Liu Shun Teng Lukasz Wojtas Guangxin Gu xiaodong shi Department of Chemistry University of South FloridaTampaFL 33620United States Department of Materials Science Fudan UniversityShanghai 200438China

Fluorescence(FL)active 8-aryl guanosine derivatives were prepared and applied for cation mediated self-assembly to form the H-bonded G_(8)-*** p-cyano(p-CN)and 8-anthracene(8-An)substituted guanosines were identified to give the strongest fluorescence with the formation of G_(8)-octamers(G_(8))both in solution(NMR)and solid state(X-ray).This well-defined G_(8)-octamer system has provided the first direct evidence on the self-assembled G-quadruplex fluorescence emission with aggregation-induced emission(AIE),which could be applied as the foundation for FL molecular probe design toward G-quadruplex recognition.

关键词： Self-assembly H-bonding G_(4)-quartet Fluorescence Aggregation induced emission

Achieving a stable COF with the combination of“flat”and“twist”large-size rigid synthons for selective gas adsorption and separation

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Chinese Chemical Letters 2022年第6期33卷 3017-3020页

作者： Jingyang Li Ying He Yongcun Zou Yan Yan Zhiguang Song xiaodong shi State key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China University of South Florida TampaFL 33620United States

A new type of covalent organic framework(COF)was achieved using combination of structrally rigid and conformationally othorganal building *** N-2-aryl-substituted triazole derivative(NAT-CHO)was prepared with co-planar conformation among the three aromatic rings as the“flat”building *** 4,4,4,4-(ethene-1,1,2,2-tetrayl)tetraaniline)(ETTA)was applied as the“twist”building block.A 2 D sheet of network was obtained through imine *** resulting NAT-COF gave excellent thermal and chemical stability,survived aqueous solutions from p H 5 to *** large-size building blocks,the porous framework NAT-COF gave efficient gas adsorption with excellent selectivity of C3 propane over C1 me-thane,suggesting its potential application for selective gas capture and separation.

关键词： N-2-Aryl triazole ETTA Covalent organic framework Gas adsorption and separation

Reversibly switching the conformation of short peptide through in-tether chiral sulfonium auxiliary

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Chinese Chemical Letters 2018年第3期29卷 485-488页

作者： xiaodong shi Yixiang Jiang Dan Yang Hui Zhao Yuan Tian Zigang Li School of Chemical Biology and Biotechnology Peking University Shenzhen Graduate School School of Life Science and Engineering Southwest Jiaotong University

A chirality induced helicity method has been developed to modulate the peptide＇s biophysical and biochemical properties. We report herein a novel approach for reversibly switching the conformation of short constraint a-helical peptides through alkylation of the in-tether thioether and dealkylation of the chiral sulfonium. This traceless redox sensitive tagging strategy broadened our scope of CIH （chirality induced helicity） strategy and provided a valuable approach to functionalize the peptide tether.

关键词： Cyclic peptide Sulfonium Chiral center α-Helix Reversible Tether modification