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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 spectroscopy.The 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 irradiation.The 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 sample.Combined 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

A Novel CdS/g-C3N4 Composite Photocatalyst： Preparation, Characterization and Photocatalytic Performance with Different Reaction Solvents under Visible Light Irradiation

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Chinese Journal of Chemistry 2017年第2期35卷 217-225页

作者： xiangju ye Xia Dai Sugang Meng Xianliang Fu Shifu Chen College of Chemistry and Materials Engineering Anhui Science and Technology University Fengyang Anhui 233100 China College of Chemistry and Materials Science Huaibei Normal University Huaibei Anhui 235000 China

CdS/graphtic carbon nitride （CdS/g-C3N4） hybrid materials were fabricated by thermal polymerization and hy- drothermal methods using Cd（CH3COO）2-2H2O, thioacetamide, and melamine as precursors. The structural and op- tical properties of the as-synthesized samples were investigated by X-ray powder diffraction, UV-Vis diffuse reflec- tance spectroscopy, scanning electron microscopy, transmission electron microscopy, etc. A coupled system toward the selective oxidation of benzyl alcohol to benzaldehyde and the reduction of nitrobenzene into aniline was used to estimate the photocatalytic performance of CdS/g-C3N4 composite photocatalysts under visible light illumination. Results indicate that the CdS/g-C3N4 sample exhibits an outstanding photocatalytic performance for selective oxida- tion of benzyl alcohol and reduction of nitrobenzene. Meanwhile, benzotrifluoride is the best reaction medium among the screened solvents. Further research demonstrates that the selective oxidation of benzyl alcohol to ben- zaldehyde is induced by the photoexcited holes and the reduction of nitrobenzene into aniline is triggered by the photoexcited electrons. Additionally, the catalyst can be recycled several times without noticeable deactivation.

关键词： CdS g-C3N4 photocatalyst selective oxidation reduction

A new phosphidation route for the synthesis of NiPx and their cocatalytic performances for photocatalytic hydrogen evolution over g-C3N4

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Journal of Energy Chemistry 2020年第9期29卷 241-249,I0008页

作者： Ziqun Wang Longfeng Li Mingzhu Liu Tifang Miao xiangju ye Sugang Meng Shifu Chen Xianliang Fu College of Chemistry and Material Science Huaibei Normal UniversityHuaibei 235000AnhuiChina Department of Chemistry Anhui Science and Technology UniversityFengyang 233100AnhuiChina

Ni-based phosphides(NiPx)composed of earth-abundant elements are promising cocatalysts to replace noble metals for photocatalytic H2 evolution reaction(HER).A safe,energy-saving,and compositioncontrollable synthesis of NiPx is still highly desired.A facile and mild solvothermal process was developed for the first time for selective synthesis of a series of NiPx,including Ni,Ni12P5,Ni2P/Ni12P5,Ni/Ni2P and Ni2P,through controlling the dosage of NaBH4 and NaH2PO2.The phosphidation process was mainly composed of(1)a sequential reduction of Ni2+to Nj0 and(H2PO2)-to P(around the formed Ni0)triggered by NaBH4,and(2)a final phosphidation between Nj0 and the in situ generated P atoms.The photocatalytic HER performance of g-C3N4 can be substantially improved with the decoration of NiPx(3 wt%)as the separation of photoinduced charge carriers can be promoted and some active sites with low over-potential for HER can be introduced.The cocatalytic efficiency of NiPx is mainly determined by P content.Ni2P with a high ratio of P consequently exhibits the highest HER performance(215.1 umol g-1 h-1),which is almost six times higher than that of the pristine g-C3N4(35.6 umol g-1 h-1).Thus,as for the cocatalyst based on Ni phosphides,Ni2P is the preferable crystal phase and more efforts should be devoted to Ni2P to further optimize its structure,texture,and morphology in future works.

关键词： Ni-phosphides Carbon nitrides Photocatalysis Hydrogen production Solvothermal synthesis

Commentary:Mammokine directs beige adipocytes to reserve energy for milk production in breast

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1472-1476页

作者： Lina Tang Jianping ye Metabolic Disease Research Center Zhengzhou University Affiliated Zhengzhou Central HospitalZhengzhou 450007China Research Center for Basic Medicine Academy of Medical SciencesZhengzhou UniversityZhengzhou 450052China

Beige/brown adipocytes play a crucial role in regulating the body’s overall energy balance.The thermogenic function is under the influence of various tissues,including the brain,muscles,and liver.However,the breast t... 详细信息

关键词： Beige Breast Epitheliail cells scRNA-seq Thermogenesis

A modified stochastic model for LS+AR hybrid method and its application in polar motion short-term prediction

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Geodesy and Geodynamics 2024年第1期15卷 100-105页

作者： Fei ye Yunbin Yuan State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China BeiDou High-precision Satellite Navigation and Location Service Hunan Engineering Research Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China Hunan Continuously Operating Reference Stations(HNCORS)Data Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China

Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame conversion.Currently,least squares(LS)+auto-regressive(AR)hybrid method is one of the main techniques of PM prediction.Besides,the weighted LS+AR hybrid method performs well for PM short-term prediction.However,the corresponding covariance information of LS fitting residuals deserves further exploration in the AR model.In this study,we have derived a modified stochastic model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid method.By using the PM data products of IERS EOP 14 C04,the numerical results indicate that for PM short-term forecasting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid method.Compared to the mean absolute errors(MAEs)of PMX/PMY sho rt-term prediction of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,respectively.Besides,for the slopes of the linear regression lines fitted to the errors of each method,the growth of the prediction error of the proposed method is slower than that of the other two methods.

关键词： Stochastic model LS+AR Short-term prediction The earth rotation parameter(ERP) Observation model

Commentary:Gut microbiota reduce the risk of hyperuricemia and gout in the human body

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Acta Pharmaceutica Sinica B 2024年第1期14卷 433-435页

作者： Lin Wang Jianping ye Metabolic Disease Research Center Zhengzhou University Affiliated Zhengzhou Central HospitalZhengzhou 450007China Research Center for Basic Medicine Academy of Medical SciencesZhengzhou UniversityZhengzhou 450052China

Gout,a prevalent and painful metabolic disease often associated with obesity and aging,is caused by the deposition of urate crystals in joints,bones,or soft tissues1.Urate is an intermediate metabolite within the purine degradation pathway,predominantly derived from uric acid under physiological pH levels.Hyperuricemia occurs due to excessive uric acid production or insufficient excretion2,which is associated with various chronic diseases,including type 2 diabetes.

关键词： Uric acid Gout Microbiota Gut Uricase

Effects of microenvironment and biological behavior on the paracrine function of stem cells

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Genes & Diseases 2024年第1期11卷 135-147页

作者： Zhixin Xue Yunjun Liao ye Li The Department of Plastic and Cosmetic Surgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China

Mesenchymal stem cells(MSCs),the most well-studied cell type in the field of stem cell therapy,have multi-lineage differentiation and self-renewal potential.MsC-based thera-pies have been used to treat diverse diseases because of their ability to potently repair tissue and locally restore function.An increasing body of evidence demonstrates that paracrine func-tion is central to the effects of MsC-based therapy.Growth factors,cytokines,chemokines,extracellular matrix components,and extracellular vehicles all contribute to the beneficial ef-fects of MSCs on tissue regeneration and repair.The paracrine substances secreted by MSCs change depending on the tissue microenvironment and biological behavior.In this review,we discuss the bioactive substances secreted by MsCs depending on the microenvironment and biological behavior and their regulatory mechanisms,which explain their potential to treat human diseases,to provide new ideas for further research and clinical cell-free therapy.

关键词： Bioactive behavior Mesenchymal stem cells Microenvironment Paracrine Secretome

Building the toolbox for in vivo glia-to-neuron reprogramming

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Neural Regeneration Research 2024年第6期19卷 1171-1172页

作者： ye Xie Bo Chen Departments of Ophthalmology and Neuroscience Icahn School of Medicine at Mount Sinai

Unlike regenerative-competent species that possess a remarkable intrinsic capacity to replenish lost neurons and restore neurocircuits spontaneously, the central nervous system in adult mammals lacks the ability to compensate for the neuronal loss caused by neurodegenerative diseases or traumatic injuries resulting in permanent loss of functionality. Inspired by earlier discoveries that radial glia or astrocytes isolated from the postnatal cortex can generate neurons,

关键词： CONVERSION DISEASE

Complicated target recognition by archaeal box C/D guide RNAs

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Science China(Life Sciences) 2024年第4期67卷 631-644页

作者： Jiayin Wang Songlin Wu Keqiong ye Key Laboratory of RNA Science and Engineering CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Box C/D RNAs guide the site-specific formation of 2′-O-methylated nucleotides(Nm)of RNAs in eukaryotes and archaea.Although C/D RNAs have been profiled in several archaea,their targets have not been experimentally determined.Here,we mapped Nm in r RNAs,t RNAs,and abundant small RNAs(s RNAs)and profiled C/D RNAs in the crenarchaeon Sulfolobus islandicus.The targets of C/D RNAs were assigned by analysis of base-pairing interactions,in vitro modification assays,and gene deletion experiments,revealing a complicated landscape of C/D RNA-target interactions.C/D RNAs widely use dual antisense elements to target adjacent sites in r RNAs,enhancing modification at weakly bound sites.Two consecutive sites can be guided with the same antisense element upstream of box D or D′,a phenomenon known as doublespecificity that is exclusive to internal box D′in eukaryotic C/D RNAs.Several C/D RNAs guide modification at a single non-canonical site.This study reveals the global landscape of RNA-guided 2′-O-methylation in an archaeon and unexpected targeting rules employed by C/D RNA.

关键词： C/D RNA 2′-O-methylation archaea guide RNA RNA modification