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Chinese Chemical Letters 2011年第7期22卷 847-850页

作者： En Ju Wang guang ying chen Hainan Provincial Key Laboratory of Tropical Pharmaceutical Herb Chemistry School of Chemistry & Chemical Engineering Hainan Normal University Haikou 571158 China

The inclusion complex of β-cyclodextrin （β-CD） with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains two β-CDs, two 4-chlorobenzoic acids and twenty-nine water molecules in the asymmetric unit, and can be formulated as 2（C42H70O35）·2（CTH5O2Cl）·29（H2O）. In the crystal lattice, two β-CDs form a face-to-face dimer jointed together through hydrogen bonding between the secondary hydroxyl groups of β--CDs. Two 4-chlorobenzoic acid molecules which contact by C-Cl…π interactions are included in the β-CD dimer cavity. The β-CD dimers are arranged in brickwork-like pattern along the crystallographic a-axis. The effect of guest molecule length on the inclusion geometry was discussed by comparative study of some fl-CD complexes containing similar guests.

关键词： β-Cyclodextrin 4-Chlorobenzoic acid Inclusion complex Crystal structure C-Cl…π interaction

Sesquiterpenoids from Curcuma wenyujin dreg and their biological activities

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Chinese Chemical Letters 2016年第10期27卷 1612-1616页

作者： Hui-Feng Huang Cai-Juan Zheng guang-ying chen Wen-Qing Yin Xian Huang Zheng-Rong Mo Key Laboratory of Tropical Medicinal Plant Chemistry the Ministry of Education of China College of Chemistry and Chemical Engineering Hainan Normal University Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources the Ministry of Education of China School of Chemistry and PharmacyGuangxi Normal University Hainan Bikai Pharmaceutical Co. Ltd.

Four new sesquiterpenoids, 4,8-dioxo-6βhydroxyl-7β,l 1-epoxycarabrane （1）, 4,8-dioxo-6βhydroxyl- 7β,11-epoxycarabrane （2）, wenyujinins Q and R （3-4）, and nine known sesquiterpenoids （5-13） were isolated from the Curcuma wenyujin （C wenyujin） dreg. Their structures and relative configurations wereelucidated using 1D, 2D NMR, and HR-ESI-MS data. All the compounds were isolated for the first time from the C wenyujin dreg and evaluated for their antibacterial and antifungal activities. Compounds 3, 5- 8 exhibited strong broad-spectrum antifungal activities against tested nine pathogenic fungi.

关键词： Curcuma wenyujin dregSesquiterpenoidsAntibacterial activityAntifungal activity

New luminescent cyclometalated iridium(Ⅲ) complexes containing fluorinated phenylisoquinoline-based ligands: Synthesis, structures,photophysical properties and DFT calculations

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Chinese Chemical Letters 2016年第3期27卷 428-432页

作者： Gao-Nan Li cheng-Wei Gao Hui Xie Hao-Hua chen Dong Liu Wei Sun guang-ying chen Zhi-Gang Niu College of Chemistry and Chemical Engineering Hainan Normal University State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education Hainan Normal University

Two new fluorinated phenylisoquinoline-based iridium（Ⅲ） complexes,[Ir（f2piq）2（bipy）][PF6]（3a） and[Ir（fmpiq）2（bipy）][PF6]（3b）（f2piq = l-（2,4-difluorophenyl）isoquinoline,fmpiq = 1-（4-fluoro-2-methylphenyl）isoquinoline,bipy = 2,2＇-bipyridine）,have been synthesized and fully *** crystal X-ray diffraction study has been undertaken on complexes 3a and 3b,which show that each adopts the distorted octahedral coordination geometry with the cis-C,C＇ and trans-N,N＇ *** photoluminescence spectra of 3a and 3b exhibit yellow and orange emission maxima at 584 and 600 nm,*** frontier molecular orbital diagrams and the lowest-energy electronic transitions of 3a-3b have been calculated with density functional theory（DFT） and time-dependent DFT（TD-DFT）.The absorption and emission spectra of complex 3b is red-shifted relative to those of complex 3a,as a consequence of the nature of the methyl group.

关键词： Iridium(Ⅲ) complex Phenylisoquinoline Crystal structure Photoluminescence DFT calculation

Meroterpenoids Possessing Diverse Rearranged Skeletons with Anti-inflammatory Activity from the Mangrove-Derived Fungus Penicillium sp. HLLG-122

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Chinese Journal of Chemistry 2023年第19期41卷 2507-2517页

作者： Yu-Yue Qin Wan-Shan Li Xuan Zhang Zhang-Xin Yu Xiao-Bao Li Han-Yi chen Yan-Ru Lv Chang-Ri Han guang-ying chen Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education and Key Laboratory of Tropical Medicinal Plant Chemistry of Hainan Province College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikouHainan571158 China Key Laboratory of Medicinal and Edible Plants Resources of Hainan Province Hainan Vocational University of Science and TechnologyHaikouHainan571126 China

Fifteen new meroterpenoids, littoreanoids A—O (1—15), including three rearranged skeleton meroterpenoids (1—3), were isolated from the mangrove-derived fungus Penicillium sp. HLLG-122. Compound 1 was a novel berkeleyacetal-derived meroterpenoid featuring an unusual spirocyclic 2-oxaspiro[5.5]undeca-4,7-dien-3-one moiety. Compound 2 possessed an unusual 6/6/6/6/6 pentacyclic system with a novel 1-hydroxy-7,7-dimethyl-2-oxabicyclo[2.2.2]octan-5-yl acetate moiety. Compound 3 was an unusual 6/7/6/5/6/5/4 polycyclic systems containing a β-lactone ring. The structures and absolute configurations of new compounds were elucidated by HRESIMS, NMR spectroscopy, single crystal X-ray diffraction analysis, and electronic circular dichroism calculations. The plausible biosynthetic pathways of 1—3 were also proposed. Compounds 6 and 11 exhibited anti-inflammatory effects with IC_(50) values of 30.41 and 19.02 μmol/L, respectively. The bioactive compound 11 was selected for the investigation of preliminary mechanism using molecular docking and Western blotting experiments. Compound 11 could suppress the levels of TNF-α and IL-6, and down-regulate the protein expression of iNOS and COX-2 in RAW 264.7 cells.

关键词： Penicillium sp Terpenoids Structural elucidation Anti-inflammatory activities Conformation analysis Natural products

Aerobic oxidative desulfurization via magnetic mesoporous silica-supported tungsten oxide catalysts

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Petroleum Science 2020年第5期17卷 1422-1431页

作者： Wei Jiang Xiang Gao Lei Dong Jin Xiao Lin-Hua Zhu guang-ying chen Su-Hang Xun Chong Peng Wen-Shuai Zhu Hua-Ming Li Institute for Energy Research School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013People’s Republic of China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013People’s Republic of China School of Chemistry and Chemical Engineering Hainan Normal UniversityHaikou 571158HainanPeople’s Republic of China Dalian Research Institute of Petroleum and Petrochemicals SINOPECNankai Road 96 of Lushunkou CityDalian 116045People’s Republic of China

It is usually difficult to remove dibenzothiophenes from diesel fuels by oxidation with molecular oxygen as an *** the study,tungsten oxide was supported on magnetic mesoporous silica by calcination to form a magnetically separable catalyst for oxidative desulfurization of diesel *** tuning different calcining temperatures,the catalyst calcined at 500℃showed a high catalytic activity with molecular oxygen as the *** optimal reaction conditions,the sulfur removal of DBT reached 99.9%at 120℃after 8 ***,the removals of 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene could also get up to 98.2%and 92.3%under the same *** reaction mechanism was explored by selective quenching experiments and FT-IR spectra.

关键词： Oxidative desulfurization Molecular oxygen Magnetic separation Mesoporous structure Tungsten oxide

Bioactive natural products from a mangrove-derived fungus Stemphylium sp. 33231

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Bioactive natural products from a mangrove-derived fungus St...

Correlation between grain size,mechanical properties and deformed microstructure of Fe-20Mn-6Al-0.6C-0.15Si low-density steel

中国化学会第十届全国天然有机化学学术会议

作者： guang-ying chen Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education Hainan Normal University

＜正＞Mangrove endophytic fungi,reportedly living in a mutualistic symbiosis with their hosts against the environmental high salinity stress,used to be recognized as rich sources of biologically active natural products that were indispensable for pharmaceutical or agrochemical *** in the genus Stemphylium produced various bioactive *** them,the

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Journal of Iron and Steel Research International 2025年第1期32卷 282-292页

作者： Qi Zhang guang-hui chen Zheng-liang Xue Zheng-kun chen guang Xu State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Red Eagle Novel Refractory Materials Research Institute Zhejiang Red Eagle Group Co.Ltd.Huzhou313000ZhejiangChina

The effects of austenite grain size on the deformed microstructure and mechanical properties of an Fe-20Mn-6Al-0.6C-0.15Si(wt.%)low-density steel were *** microstructure of the experimental steel after solution treatment was single austenitic *** austenite grain size increased with solution temperature and time.A model was established to show the relationship between temperature,time and austenite grain size for the experimental *** addition,as the solution temperature increased,the strength decreased,while the elongation first increased and then *** decrease in elongation after solution treatment at 1100℃ for 90 min is contributed to the over-coarse austenite ***,after solution treatment at 900℃ for 90 min,the strength-elongation product reached the highest value of 44.4 GPa%.As the austenite grain size increased,the intensity of//tensile direction fiber *** was accompanied by a decrease in dislocation density,resulting in a lower fraction of low-angle grain boundaries and a lower work hardening ***,the austenite grain size has a critical influence on the mechanical properties of the low-density *** grains lead to a lower yield strength due to the Hall-Petch effect and a lower tensile strength because of lower dislocation strengthening.

关键词： Austenitic low-density steel Solution treatment Grain size Mechanical property Deformed microstructure

Privacy Distributed Constrained Optimization Over Time-Varying Unbalanced Networks and Its Application in Federated Learning

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 335-346页

作者： Mengli Wei Wenwu Yu Duxin chen Mingyu Kang guang cheng the School of Cyber Science and Engineering Southeast University IEEE the School of Mathematics Frontiers Science Center for Mobile Information Communication and Security Southeast University the Purple Mountain Laboratories the School of Mathematics Southeast University

This paper investigates a class of constrained distributed zeroth-order optimization(ZOO) problems over timevarying unbalanced graphs while ensuring privacy preservation among individual agents. Not taking into account recent progress and addressing these concerns separately, there remains a lack of solutions offering theoretical guarantees for both privacy protection and constrained ZOO over time-varying unbalanced *** hereby propose a novel algorithm, termed the differential privacy(DP) distributed push-sum based zeroth-order constrained optimization algorithm(DP-ZOCOA). Operating over time-varying unbalanced graphs, DP-ZOCOA obviates the need for supplemental suboptimization problem computations, thereby reducing overhead in comparison to distributed primary-dual methods. DP-ZOCOA is specifically tailored to tackle constrained ZOO problems over time-varying unbalanced graphs,offering a guarantee of convergence to the optimal solution while robustly preserving privacy. Moreover, we provide rigorous proofs of convergence and privacy for DP-ZOCOA, underscoring its efficacy in attaining optimal convergence without constraints. To enhance its applicability, we incorporate DP-ZOCOA into the federated learning framework and formulate a decentralized zeroth-order constrained federated learning algorithm(ZOCOA-FL) to address challenges stemming from the timevarying imbalance of communication topology. Finally, the performance and effectiveness of the proposed algorithms are thoroughly evaluated through simulations on distributed least squares(DLS) and decentralized federated learning(DFL) tasks.

关键词： Constrained distributed optimization decentralized federated learning (DFL) differential privacy (DP) time-varying unbalanced graphs zeroth-order gradient

Utilizing BP neural networks to accurately reconstruct the tritium depth profile in materials for BIXS

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Nuclear Science and Techniques 2025年第1期36卷 103-114页

作者： chen Zhao Wei Jin Yan Shi Chang-An chen Yi-ying Zhao Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China

β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample ***,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this *** this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is *** average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium ***,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.

关键词： β-ray-induced X-ray spectroscopy Tritium detection BP network Ridge regression Reconstruction problem

Synthesis of the tricyclic core of the neurotrophic illicinones

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Synthesis of the tricyclic core of the neurotrophic illicino...