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Synthesis of Ferrocene-Modified Carbon Nitride Photocatalysts by Surface Amidation Reaction for Phenol Synthesis

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Chinese Journal of Chemistry 2014年第6期32卷 498-506页

作者： Xiangju ye yun Zheng Xinchen Wang State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhouFujian 350002China

A polymeric Fc-CO-NH-C_(3)N_(4)(Fc-CN)material was synthesized by amidation reaction of ferrocenecarboxylic acid(Fc-COOH)with NH_(2)groups on the surface of mesoporous graphitic carbon nitride(MCN).The properties of the as-synthesized samples were characterized by X-ray diffraction,Fourier transform infrared spectroscopy,UV-Vis diffuse reflectance spectra,N2 adsorption-desorption isotherm,photoluminescence spectroscopy,transmis-sion electron microscopy,electron paramagnetic resonance,(photo)electrochemical measurement and X-ray photo-electron *** resultant catalysts were investigated as heterogeneous catalysts for the selective oxida-tion of benzene to phenol using H_(2)O_(2)as a green oxidant under visible light *** results reveal that Fc-modified samples can not only extend the visible light absorption,but also accelerate the bulk-to-surface charge transfer and separation via surface dyadic structures,both of which are favorable for phenol production from ben-zene photocatalytic hydroxylation with H_(2)O_(2).Under the optimal conditions,up to 16.9%phenol yield(based on benzene)is obtained by Fc-CN/1.5-5 sample,and the corresponding Fe content is about 0.64 wt%.Furthermore,after the second run,no significant decrease of the activity(in term of TOF)and the selectivity is found in Fc-CN/_(1.0)-5 *** with the experimental results and Fenton-chemistry,a possible photocatalytic reaction mecha-nism on the hydroxylation of benzene to phenol at neutral medium with visible light is proposed.

关键词： carbon nitride ferrocenecarboxylic acid benzene oxidation photocatalysis phenol

Consensus of a two-agent opinion dynamical system with processing delay

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International Journal of Biomathematics 2018年第6期11卷 111-128页

作者： ye Cheng Xiao Wang bao Shi School of Basic Sciences for AviationNaval Aviation University Yantai 264001 P. R. China College of Science National University of Defense Technology Changsha 410073 P. R. China

A sufficient condition is obtained for a two-agent opinion dynamical system with pro-cessing delay to experience unconditional consensus. To this end, the dynamics proposed is transformed into a general class of delay differential equation and asymptotic stability of the origin is then analyzed. It is also shown that increasing delay can prolong the time needed for the system to realize consensus and even induce a Hopf bifurcation.

关键词： Opinion dynamical system consensus processing delay asymptotic stability Hopf bifurcation.

Comparative analysis of empirical and deep learning models for ionospheric sporadic E layer prediction

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Earth and Planetary Physics 2025年第1期9卷 10-19页

作者： BingKun Yu PengHao Tian XiangHui Xue Christopher JScott HaiLun ye JianFei Wu Wen Yi TingDi Chen XianKang Dou Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230088China CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China Department of Meteorology University of ReadingReading RG66BBUK

Sporadic E(Es)layers in the ionosphere are characterized by intense plasma irregularities in the E region at altitudes of 90-130 *** they can significantly influence radio communications and navigation systems,accurate forecasting of Es layers is crucial for ensuring the precision and dependability of navigation satellite *** this study,we present Es predictions made by an empirical model and by a deep learning model,and analyze their differences comprehensively by comparing the model predictions to satellite RO measurements and ground-based ionosonde *** deep learning model exhibited significantly better performance,as indicated by its high coefficient of correlation(r=0.87)with RO observations and predictions,than did the empirical model(r=0.53).This study highlights the importance of integrating artificial intelligence technology into ionosphere modelling generally,and into predicting Es layer occurrences and characteristics,in particular.

关键词： ionospheric sporadic E layer radio occultation ionosondes numerical model deep learning model artificial intelligence

Design synthesis and biological evaluation of 3-substituted triazole derivatives

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Chinese Chemical Letters 2011年第5期22卷 519-522页

作者： bao Gang Wang Shi Chong Yu Xiao yun Chai Yong Zheng Yan Hong Gang Hu Qiu ye Wu Department of Organic Chemistry School of Pharmacy Second Military Medical University Shanghai 200433 China Pharmacy Team Administrative Brigade of Postgraduate Second Military Medical University Shanghai 200433 China

Based on the active site of lanosterol 14α-demethylase of azole antifungal agents,sixteen 1-（1H-1,2,4-triazole-1-yl）- 2-（2,4- difluorophenyl）-3-（N-n-butyl-N-1-substitutedbenzyl-4-methylene-1H-1,2,3-triazole）-2-propanols have been designed,synthesized and evaluated as antifungal *** of preliminary antifungal tests against eight human pathogenic fungi in vitro showed that some of the compounds exhibited excellent activities with broad spectrum.

关键词： Synthesis Triazole Antifungal activity 1 3-Dipolar cycloaddition

Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

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Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： Jian Li Wen Yi XiangHui Xue Jie Zeng HaiLun ye JianYuan Wang JinSong Chen Na Li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

Neuroprotective effects of neural stem cells pretreated with neuregulin1β on PC12 cells exposed to oxygen-glucose deprivation/reoxygenation

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Neural Regeneration Research 2023年第3期18卷 618-625页

作者： Qiu-Yue Zhai Yuan-Hua ye Yu-Qian Ren Zhen-Hua Song Ke-Li Ge bao-He Cheng yun-Liang Guo Institute of Cerebrovascular Diseases Medical Research CenterThe Affiliated Hospital of Qingdao UniversityTaishan Scholars Construction Project Excellent Innovative Team of Shandong ProvinceQingdaoShandong ProvinceChina Department of Obstetrics The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina Research Center of Stem Cells Shandong Haoyun International Hospital of Stem CellsJinanShandong ProvinceChina

Studies on ischemia/reperfusion(I/R)injury suggest that exogenous neural stem cells(NSCs)are ideal candidates for stem cell therapy reperfusion ***,NSCs are difficult to obtain owing to ethical *** addition,the survival,differentiation,and proliferation rates of transplanted exogenous NSCs are low,which limit their clinical *** previous study showed that neuregulin1β(NRG1β)alleviated cerebral I/R injury in *** this study,we aimed to induce human umbilical cord mesenchymal stem cells into NSCs and investigate the improvement effect and mechanism of NSCs pretreated with 10 nM NRG1βon PC12 cells injured by oxygen-glucose deprivation/reoxygenation(OGD/R).Our results found that 5 and 10 nM NRG1βpromoted the generation and proliferation of ***-culture of NSCs and PC12 cells under condition of OGD/R showed that pretreatment of NSCs with NRG1βimproved the level of reactive oxygen species,malondialdehyde,glutathione,superoxide dismutase,nicotinamide adenine dinucleotide phosphate,and nuclear factor erythroid 2-related factor 2(Nrf2)and mitochondrial damage in injured PC12 cells;these indexes are related to *** has reported that p53 and solute carrier family 7 member 11(SLC7A11)play vital roles in ferroptosis caused by cerebral I/R *** data show that the expression of p53 was increased and the level of glutathione peroxidase 4(GPX4)was decreased after RNA interference-mediated knockdown of SLC7A11 in PC12 cells,but this change was alleviated after co-culturing NSCs with damaged PC12 *** findings suggest that NSCs pretreated with NRG1βexhibited neuroprotective effects on PC12 cells subjected to OGD/R through influencing the level of ferroptosis regulated by p53/SLC7A11/GPX4 pathway.

关键词： ferroptosis p53 SLC7A11 GPX4 human umbilical cord-mesenchymal stem cells neural stem cells neuregulin1β neuroprotection oxygen-glucose deprivation/reoxygenation PC12 cell

Preference transfer model in collaborative filtering for implicit data

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Frontiers of Information Technology & Electronic Engineering 2016年第6期17卷 489-500页

作者： Bin JU yun-tao QIAN Min-chao ye Institute of Artificial Intelligence College of Computer Science and TechnologyZhejiang UniversityHangzhou 3100Z7China Health Information Center of Zhejiang Province Hangzhou 310006China

Generally, predicting whether an item will be liked or disliked by active users, and how much an item will be liked, is a main task of collaborative filtering systems or recommender systems. Recently, predicting most likely bought items for a target user, which is a subproblem of the rank problem of collaborative filtering, became an important task in collaborative filtering. Traditionally, the prediction uses the user item co-occurrence data based on users' buying behaviors. However, it is challenging to achieve good prediction performance using traditional methods based on single domain information due to the extreme sparsity of the buying matrix. In this paper, we propose a novel method called the preference transfer model for effective cross-domain collaborative filtering. Based on the preference transfer model, a common basis item-factor matrix and different user-factor matrices are *** user-factor matrix can be viewed as user preference in terms of browsing behavior or buying behavior. Then,two factor-user matrices can be used to construct a so-called ‘preference dictionary' that can discover in advance the consistent preference of users, from their browsing behaviors to their buying behaviors. Experimental results demonstrate that the proposed preference transfer model outperforms the other methods on the Alibaba Tmall data set provided by the Alibaba Group.

关键词： Recommender systems Collaborative filtering Preference transfer model Cross domain Implicit data

Dramatical enhancement of circular dichroism in chiral hybrid perovskites via carboxylic hydrogen bond engineering

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Science China Chemistry 2025年

作者： Hang Li Xinling Li Peng Wang Tingting Zhu Ruiqing Li Huang ye Yaru Geng Hongliang Dai Junhua Luo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Fujian College University of Chinese Academy of Sciences College of Chemistry Fuzhou University College of Chemistry and Materials Key Laboratory of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal University

Chiral hybrid perovskites （CHPs） have been regarded as promising candidates for developing chiroptoelectronics ***,circular dichroism （CD）,as one of the most important characteristics to evaluate the chiroptical activity,remains at a comparatively low level in CHPs compared to other chiral materials,which hinders the successful applications of CHPs in stateof-the-art ***,exploring new methods for enhancing CD in CHPs is urgently needed and remains ***,enhanced CD response has been successfully realized via constructing carboxylic hydrogen bonding in chiralachiral mixed cations perovskites （R/S-PPA）2（ABA）PbBr5（2R/2S）(PPA=1-phenylpropylamine,ABA=4-aminobutyric acid).Compared with the prototype （R/S-PPA）PbBr3（1R/1S）,2R/2S provide intimate connections between organic units and inorganic parts via carboxylic hydrogen bonding N–H···O bridge,contributing new chirality transfer paths.A larger inorganic skeletons’helicity in 2R/2S predicts a high degree of chirality ***,2R/2S exhibit significantly enhanced CD response with an anisotropy factor amplified by an order of ***,bright blue circularly polarized luminescence applications are achieved in 2R/*** work systematically investigates the correlation between CD and hydrogen bonding interaction in CHPs,meanwhile providing a new avenue to develop the application potential of chiral materials in chiroptoelectronics.

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Effect of C/N Concentration Fluctuation on Formation of Plasma Electrolytic Carbonitriding Coating on Q235

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Journal of Iron and Steel Research International 2012年第11期19卷 39-45页

作者： JIANG Yong-feng bao ye-feng YANG Ke College of Mechanical and Electrical Engineering Hohai UniversityChangzhou 213022JiangsuChina

The plasma electrolytic carbonitriding （PEC/N） on the Q235 steel was investigated in an aqueous solution containing monoethanolamine and KC1 in a very short period of time. The microdischarge characteristics of the volt- age/current on the Q235 were observed using real-time imaging during the PEC/N. The microstructure and element distribution of the carbonitriding layer were examined using scanning electron microscope （SEM） equipped with energy dispersive spectroscope （EDS）. The effect of microdischarge on roughness, thickness and microhardness was evalua- ted. The formation of the carbonitriding layer was discussed. Research shows that it is similar in the microstructure and properties between the plasma electrolytic carbonitriding and the traditional gas carbonitriding. The formation of the carbonitriding layer results from the carbon and nitrogen fluctuation in PEC/N process. The microhardness and thickness can be up to HV 779 and 0. 360 mm in 180 s, respectively, which is close to the results of the gas carboni- triding in the microhardness. Therefore, the plasma electrolytic carbonit^riding has a potential to substitute the gas carbonitriding.

关键词： plasma electrolytic carbonitriding coating microstructure Q235