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Preparation of Co/s co-doped carbon catalysts.f.r excellent methylene blue degradation

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 169-181页

作者： Haixu Li Haobo He Tiannan Jiang Yunfei Du Zhichen Wu Liang Xu Xinjie Wang Xiaoguang Liu Wanhua Yu Wendong xue school of Materials science and Engineering University of Science and Technology BeijingBeijing 100083China Beijing Jinyu Tongda Refractory Technologies Co. Ltd.Beijing 100085China

s and Co co-doped carbon catalysts were prepared via pyrolysis of MOf-71 and thiourea mixtures at 800℃at a mass ratio of MOf-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMs.f.r methylene blue(MB)*** effects of two different mixing routes were identified on the MB degradation ***,the catalyst obtained by the alcohol solvent evaporation(MOf-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was.f.ster than that derived from the direct grinding method(MOf-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-s content of MOf-AEP(43.39at%)was less than that of MOf-DGP(54.73at%),and the proportion of C-s-C in MOf-AEP(13.56at%)was higher than that of MOf-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMs was -2.94 eV when sulfur was doped as C-s-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-s bond(-2.86 eV).Thus,the C-s-C sites might provide more contributions to activate PMs compared with ***,the degradation parameters,including pH and MOf-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.

关键词： advanced oxidation process alcohol solvent evaporation hydrogen bond s and Co co-doped carbon catalysts wastewater remediation

Cobalamin-dependent radical s-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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science China Chemistry 2025年第1期68卷 308-316页

作者： sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng xue Xiaokun Xu Guannan Zhong Yuanyuan shi Bin Hong Xiaoying Bian Wen Liu state Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences state Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical s-adenosyl-L-methionine(sAM) proteins constitute the largest collection of the radical sAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical sAM protein, with Cxm9, a DUf5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-s-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUf5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical sAM activity.

关键词： cbl-dependent radical sAM protein biosynthesis chuangxinmycin stereoselective methylation

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

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Neural Regeneration Research 2025年第7期20卷 2038-2052页

作者： Zhihao Lin Changzhou Ying Xiaoli si Naijia xue Yi Liu Ran Zheng Ying Chen Jiali Pu Baorong Zhang Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra ***,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic ***,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely *** oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains *** aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what *** found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease *** oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic ***,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model ***,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic ***,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced *** findings demonstrate that NADPH oxidase 4 promotes.f.rroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

关键词： dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) neuroinflammation Parkinson's disease

A sMALLEsT sINGULAR VALUE METHOD fOR sOLVING INVERsE EIGENVALUE PROBLEMs

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Journal of Computational Mathematics 1996年第1期14卷 23-31页

作者： s.f. Xu(Department of Mathematics, Peking University, Beijing) 北京大学数学系北京

Utilizing the properties of the smallest singular value of a matrix, we propose a new, efficient and reliable algorithm for solving nonsymmetric matrix inverse eigenvalue problems, and compare it with a known method. ... 详细信息

关键词： Math A sMALLEsT sINGULAR VALUE METHOD fOR sOLVING INVERsE EIGENVALUE PROBLEMs

seismic fragility assessment of RC frame structure designed according to modern Chinese code for seismic design of buildings

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 331-342页

作者： D. Wu s. Tesfamariam s.f. stiemer D. Qin Key Laboratory of Earthquake Engineering and Applied Technique of Guangdong Province Guangzhou 501405 China school of Engineering University of British Columbia Kelowna V1 V 1 V7 Canada Dept. of Civil Engineering University of British Columbia Vancouver V6T 1Z4 Canada Dept. of Civil Engineering Radio Film and Television Design and Research Institute Beijing 100045 China

following several damaging earthquakes in China, research has been devoted to find the causes of the collapse of reinforced concrete （RC） building sand studying the vulnerability of existing buildings. The Chinese Code for seismic Design of Buildings （CCsDB） has evolved over time, however, there is still reported earthquake induced damage of newly designed RC buildings. Thus, to investigate modern Chinese seismic design code, three low-, mid- and high-rise RC frames were designed according to the 2010 CCsDB and the corresponding vulnerability curves were derived by computing a probabilistic seismic demand model （PsDM）.The PsDM was computed by carrying out nonlinear time history analysis using thirty ground motions obtained from the Pacific Earthquake Engineering Research Center. finally, the PsDM was used to generate fragility curves.f.r immediate occupancy, significant damage, and collapse prevention damage levels. Results of the vulnerability assessment indicate that the seismic demands on the three different frames designed according to the 2010 CCsDB meet the seismic requirements and are almost in the same s.f.ty level.

关键词： building damage criteria collapse ratio probabilistic seismic demand model (PsDM) fragility curves Chinese Code for seismic Design of Buildings (CCsDB)

EZH2-dependent myelination following sciatic nerve injury

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Neural Regeneration Research 2025年第8期20卷 2382-2394页

作者： Hui Zhu Li Mu Xi Xu Tianyi Huang Ying Wang siyuan Xu Yiting Wang Wencong Wang Zhiping Wang Hongkui Wang Chengbin xue Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityKey Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Medical school of Nantong University NantongJiangsu ProvinceChina Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Rehabilitation Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Critical Care Medicine Nantong Fourth People’s HospitalNantongJiangsu ProvinceChina

Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve ***,the gene regulatory network of regenerated myelin differs.f.om that of native *** of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of schwann cells in *** further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were *** results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain *** highlights the crucial role of Ezh2 in initiating schwann cell ***,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type *** suggests that the absence of Ezh2 in schwann cells impairs myelin formation and *** conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve *** EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

关键词： demyelination EZH2 myelination peripheral nerve injury PRC2 remyelination schwann cells sciatic nerve crush sciatic nerve transection

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期7卷 32-49页

作者： Li-Rong Xiao Chen Chen shuo Wang Zi-Yin Dai Hideo Kimura Cui Ni Chuan-Xin Hou xue-Qin sun si-Jie Guo Wei Du Xiu-Bo Xie school of Environmental and Material Engineering Yantai University Bosch HUAYU steering systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville shandong Key Laboratory of Eco-Environmental science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with Ni,Na,sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys solid hydrogen storage Transition metal elements

Deciphering the mechanobiology of microglia in traumatic brain injury with advanced microsystems

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Neural Regeneration Research 2025年第8期20卷 2304-2306页

作者： Anthony Procès sylvain Gabriele Univ.Grenoble Alpes InsermU1216Grenoble Institut des NeurosciencesGrenobleFrance Mechanobiology&Biomaterials Group CIRMAPResearch Institute for BiosciencesUniversity of MonsMonsBelgium

Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results.f.om a mechanical insult to the brain,leading to neuronal and axonal damage and subsequently causing a secondary *** minutes ... 详细信息

关键词： traumatic injury damage

A Comparative study of Boron and Phosphorus Doping Effects in siC: H films Prepared by ECR-CVD

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Journal of Materials science & Technology 1998年第1期14卷 65-71页

作者： s.f. Yoon (school of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue,singapore 639798, Rep. of singapore) school of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 Nanyang Avenue Singapore

Hydrogenated silicon carbide films (siC:H) were deposited using the electron cyclotron resonance chemical vapour deposition (ECR-CVD) technique from a mixture of methane, silane and hydrogen, and using diborane and phosphine as doping gases. The effects of changes in the microwave power on the deposition rate and optical bandgap were investigated, and variations in the photoand dark-conductivities and activation energy were studied in conjunction with film analysis using the Raman scattering technique. In the case of boron-doped samples, the conductivity increased rapidly to a maximum, followed by rapid reduction at high microwave power. The ratio of the photo- to dark-conductivity (σph/σd) peaked at microwave power of ~600 W. Under conditions of high microwave power, Raman scattering analysis showed evidence of the formation and increase in the silicon microcrystalline and diamond-like phases in the films, the former of which could account for the rapid increase and the latter the subsequent decrease in the *** the case of phosphorusdoped siC:H samples, it was.f.und that increase in the microwave power has the effect of enhancing the formation of the silicon microcrystalline phase in the films which occurred in correspondence to a rapid increase in the conductivity and reduction in the activation energy The conductivity increase stabilised in samples deposited at microwave power exceeding 500 W probably as a result of dopant saturation. Results.f.om Raman scattering measurements also showed that phosphorus doping had the effect of enhancing the formation of the silicon microcrystals in the film whereas the presence of boron had the effect of preserving the amorphous structure.

关键词： ECR A Comparative study of Boron and Phosphorus Doping Effects in siC H films Prepared by ECR-CVD