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Strategic regulation of nitrogen-containing intermediates for enhanced nitrate reduction over Co_(3)O_(4)/SiC catalyst having multiple active centers

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Journal of Energy Chemistry 2024年第9期96卷 291-299页

作者： ming-hao guan hao-Nan Xu Jin Liu Tao Wu An-Hui Lu State Key Laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Regulating the intermediates involved in the electrocatalytic nitrate reduction reaction(NO_(3)RR)is crucial for the enhancement of reaction ***,it remains a great challenge to regulate the reaction intermediates through active site manipulation on the surface of the ***,a family of n%-Co_(3)O_(4)/SiC(n=5,8,12,20)catalysts with a delicate percentage of Co^(2+)and Co^(3+)were prepared for NO_(3)*** found that Co^(3+)primarily acts as the active site for NO_(3)^(−)reduction to NO_(2)^(−),while Co^(2+)is responsible for the conversion of NO_(2)^(−)to NH_(3).Moreover,the conversion of these intermediates over the active sites is autonomous and separately *** processes synergistically accomplish the reduction of nitrate ions to synthesize *** the experimental studies and density functional theory(DFT)calculations,it is discovered the pathway(^(*)NHO→^(*)NHOH→^(*)NH_(2)OH→^(*)NH_(2)→^(*)NH_(3))is more favorable due to the lowerΔG value(0.25 eV)for the rate-limiting step(^(*)NO→^(*)NHO).The NH_(3)yield rate of 8%-Co_(3)O_(4)/SiC reached 1.08 mmol/(cm^(2)h)with a Faradaic efficiency of 96.4%at−0.89 V versus the reversible hydrogen electrode(RHE),surpassing those of most reported non-noble NO_(3)RR *** strategy not only provides an efficient catalyst for NO_(3)RR but also serves as an illustrative model for the regulation of multi-step reaction intermediates through the design of distinct active sites,thereby presenting a new approach to enhance the efficiency of intricate reactions.

关键词： Electrocatalysis Nitratereduction Co_(3)O_(4)/SiC catalysts Intermediates control

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Mesoporous Fe-Doped Carbon Electrocatalysts with Highly Exposed Active Sites for Efficient Synthesis of Hydrogen Peroxide and Tandem Epoxidation of Propene

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Renewables 2023年第5期1卷 562-571页

作者： Ling-Yu Dong ming-hao guan Yong-Qi Ren guang-Ping hao An-Hui Lu State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsLiaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024

Catalytic tandem synthesis of fine chemicals using the in situ-formed intermediates by electrocatalytic reactions has increasingly attracted attention in recent *** difficulty lies in the low local concentration of intermediates because of the slow formation rates in the catalytically electrochemical *** showcase an efficient tandem epoxidation of propene,which is accelerated by the in situ-generated hydrogen peroxide(H_(2)O_(2)).The catalysts of iron-doped tubular mesoporous carbons feature ultrathin carbon walls and record-high exposed external surface areas,which enable a H_(2)O_(2) formation rate of 747.7 mmol gcat^(-1) h^(-1) at 0.4 V versus reversible hydrogen electrode,together with a H_(2)O_(2) Faradaic efficiency of nearly 100%.A positive correlation between the exposed external surface area and the oxygen reduction activity is experimentally *** utilizing the in situ-generated H_(2)O_(2),the tandem epoxidation of propylene displays a yield rate of 80.3μmol gTS-1^(-1) h^(-1) for propylene *** high performance originates from the high local concentration of H_(2)O_(2) surrounding the titanium silicalite-1 catalysts for propylene *** results may inspire other tandem electrochemical reactions by using the mesoporous catalysts for synthesis of building block chemicals.

关键词： hydrogen peroxide mesoporous carbon electrocatalysts propylene epoxidation tandem reactions

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MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen Wang Wei ming Longfu Chen Tianliang Song Moxi Yele hao Zhang Long Yang Gegen Sarula Benliang Liang Luting Yan guangsheng Wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen ming-ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Brain functional connectivity network studies of acupuncture： a systematic review on resting-state fMRI

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Journal of Integrative Medicine 2018年第1期16卷 26-33页

作者： Rong-lin Cai Guo-ming Shen hao Wang Yuan-yuan guan Graduate School of Anhui University of Chinese Medicine Hefei 230012 Anhui Province China School of Integrated Traditional Chinese & Western Medicine Anhui University of Chinese Medicine Hefei 230012 Anhui Province China

Background： Functional magnetic resonance imaging （fMRI） is a novel method for studying the changes of brain networks due to acupuncture treatment. In recent years, more and more studies have focused on the brain functional connectivity network of acupuncture stimulation. Objective： To offer an overview of the different influences of acupuncture on the brain functional connec- tivity network from studies using resting-state fMRI. Search strategy： The authors performed a systematic search according to PRISMA guidelines, The database PubMed was searched from January 1, 2006 to December 31, 2016 with restriction to human studies in English language. Inclusion criteria： Electronic searches were conducted in PubMed using the keywords ＂acupuncture＂ and ＂neuroimaging＂ or ＂resting-state fMRI＂ or ＂functional connectivity＂, Data extraction and analysis： Selection of included articles, data extraction and methodological quality assessments were respectively conducted by two review authors. Results： Forty-four resting-state fMRI studies were included in this systematic review according to inclu- sion criteria. Thirteen studies applied manual acupuncture vs. sham, four studies applied electro- acupuncture vs. sham, two studies also compared transcutaneous electrical acupoint stimulation vs. sham, and nine applied sham acupoint as control. Nineteen studies with a total number of 574 healthy subjects selected to perform fMRI only considered healthy adult volunteers. The brain functional connec- tivity of the patients had varying degrees of change. Compared with sham acupuncture, verum acupunc- ture could increase default mode network and sensorimotor network connectivity with pain-, affective- and memory-related brain areas. It has significantly greater connectivity of genuine acupuncture between the periaqueductal gray, anterior cingulate cortex, left posterior cingulate cortex, right anterior insula, limbic/paralimbic and precuneus compared with sham acupuncture. Some research h

关键词： Resting-state functional magnetic resonance Acupuncture Functional connectivity Functional network Complementary medicine Alternative medicine

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Optoelectronic parametric oscillator

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Light(Science & Applications) 2020年第1期9卷 1028-1037页

作者： Tengfei hao Qizhuang Cen Shanhong guan Wei Li Yitang Dai Ninghua Zhu ming Li State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Oscillators are one of the key elements in various applications as a signal source to generate periodic *** them,an optical parametric oscillator(OPO)is a driven harmonic oscillator based on parametric frequency conversion in an optical cavity,which has been widely investigated as a coherent light source with an extremely wide wavelength tuning ***,steady oscillation in an OPO is confined by the cavity delay,which leads to difficulty in frequency tuning,and the frequency tuning is discrete with the minimum tuning step determined by the cavity ***,we propose and demonstrate a counterpart of an OPO in the optoelectronic domain,i.e.,an optoelectronic parametric oscillator(OEPO)based on parametric frequency conversion in an optoelectronic cavity to generate microwave *** to the unique energy-transition process in the optoelectronic cavity,the phase evolution in the OEPO is not linear,leading to steady single-mode oscillation or multimode oscillation that is not bounded by the cavity ***,the multimode oscillation in the OEPO is stable and easy to realize owing to the phase control of the parametric frequency-conversion process in the optoelectronic cavity,while stable multimode oscillation is difficult to achieve in conventional oscillators such as an optoelectronic oscillator(OEO)or an OPO due to the mode-hopping and mode-competition *** proposed OEPO has great potential in applications such as microwave signal generation,oscillator-based computation,and radio-frequency phase-stable transfer.

关键词： effect oscillator parametric

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Crystal structures of GI.8 Boxer virus P dimers in complex with HBGAs, a novel evolutionary path selected by the Lewis epitope

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Protein & Cell 2015年第2期6卷 101-116页

作者： Ning hao Yutao Chen ming Xia ming Tan Wu Liu Xiaotao guan Xi Jiang Xuemei Li National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Division of Infectious Diseasess Cincinnati Children's Hospital Medical Center Cincinnati OH 45229 USA University of Cincinnati College of Medicine Cincinnati OH 45267 USA

Human noroviruses （huNoVs） recognize histo-blood group antigens （HBGAs） as attachment factors, in which genogroup （G） I and GII huNoVs use distinct binding interfaces. The genetic and evolutionary relationships of GII huNoVs under selection by the host HBGAs have been well elucidated via a number of structural studies; however, such relationships among GI NoVs remain less clear due to the fact that the structures of HBGA-binding interfaces of only three GI NoVs with similar binding profiles are known. In this study the crystal structures of the P dimers of a Lewis-binding strain, the GI.8 Boxer virus （BV） that does not bind the A and H antigens, in complex with the Lewis b （Le^b） and Ley antigens, respectively, were determined and compared with those of the three previously known GI huNoVs, i.e. GI.1 Nor- walk virus （NV）, GI.2 FUV258 （FUV） and GI.7 TCH060 （TCH） that bind the A/HILe antigens. The HBGA binding interface of BV is composed of a conserved central binding pocket （CBP） that interacts with the β-galactose of the precursor, and a well-developed Le epitope-bind- ing site formed by five amino acids, including three consecutive residues from the long P-loop and one from the S-loop of the P1 subdomain, a feature that was not seen in the other GI NoVs. On the other hand, the H epitope/acetamido binding site observed in the other GI NoVs is greatly degenerated in BV. These data explain the evolutionary path of GI NoVs selected by the poly- morphic human HBGAs. While the CBP is conserved, the regions surrounding the CBP are flexible, providingfreedom for changes. The loss or degeneration of the H epitope/acetamido binding site and the reinforcement of the Le binding site of the GI,8 BV is a typical example of such change selected by the host Lewis epitope.

关键词： norovirus P domain histo-blood groupantigens (HBGAs) crystal structure norovirus-hostinteraction

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In-situ investigation on the fatigue crack propagation behavior in ferrite-pearlite and dual-phase ferrite-bainite low carbon steels

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Science China(Technological Sciences) 2013年第1期56卷 71-79页

作者： guan mingFei YU hao School of Materials Science and Engineering University of Science and Technology Beijing

The purpose of this study was to describe the roles of microstructure types and grain boundary characteristics in fatigue crack propagation behavior in ferrite-pearlite steel and ferrite-bainite *** ferrite-bainite dual-phase steel was obtained by intermediate heat treatment conducted on ferrite-pearlite low carbon *** paper presents the results from investigation using constant stress-controlled fatigue tests with in-situ scanning electron microscopy(SEM),electron backscattering diffraction(EBSD) and fatigue fractography *** images arrested by in-situ SEM showed that the second hard bainite phase distributed in the soft ferrite matrix had a significant effect on preventing the cracks opening compared with pearlite,and that the cracks in ferrite-bainite steel were "locked" in the second hard bainite phase while the crack propagation path in ferrite-pearlite steel was more ***,the fatigue fracture surface analysis and the coincidence site lattice(CSL) obtained by EBSD indicated that low-CSL grain boundaries in ferrite-bainite steel distributed more uniformly,which has a more significant effect on the resistance of crack *** was revealed that ferrite-bainite dual-phase microstructures could inhibit the fatigue crack propagation more effectively than ferrite-pearlite microstructures.

关键词： fatigue crack propagation behavior in-situ SEM ferrite-bainite microstructures grain boundaries

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Large-scale coherent Ising machine based on optoelectronic parametric oscillator

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Light(Science & Applications) 2022年第12期11卷 2972-2981页

作者： Qizhuang Cen hao Ding Tengfei hao Shanhong guan Zhiqiang Qin Jiaming Lyu Wei Li Ninghua Zhu Kun Xu Yitang Dai ming Li State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijingChina School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijingChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijingChina School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghaiChina Peng Cheng Laboratory ShenzhenChina

Ising machines based on analog systems have the potential to accelerate the solution of ubiquitous combinatorial optimization *** some artificial spins to support large-scale Ising machines have been reported,e.g.,superconducting qubits in quantum annealers and short optical pulses in coherent Ising machines,the spin stability is fragile due to the ultra-low equivalent temperature or optical phase *** this paper,we propose to use short microwave pulses generated from an optoelectronic parametric oscillator as the spins to implement a large-scale Ising machine with high *** proposed machine supports 25,600 spins and can operate continuously and stably for ***,the proposed Ising machine is highly compatible with high-speed electronic devices for programmability,paving a low-cost,accurate,and easy-to-implement way toward solving real-world optimization problems.

关键词： stability oscillator coherent

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三角梅主要品种表型性状分析

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热带作物学报 2025年第1期46卷 70-82页

作者：郝晓函关文灵李叶芳宋杰云南农业大学园林园艺学院云南昆明650201 云南省农业科学院花卉研究所/国家观赏园艺工程技术研究中心/云南省花卉育种重点实验室云南昆明650205 吉林省种子管理总站吉林长春130031

三角梅是我国南方重要的木本花卉,品种繁多,但分类比较混乱。本研究以云南引种保存的133个三角梅品种为研究对象,对133个品种的10个数量性状和41个质量性状进行频率分布统计、变异系数计算和多样性指数计算,并进行Q型聚类分析。结果表明... 详细信息

三角梅是我国南方重要的木本花卉,品种繁多,但分类比较混乱。本研究以云南引种保存的133个三角梅品种为研究对象,对133个品种的10个数量性状和41个质量性状进行频率分布统计、变异系数计算和多样性指数计算,并进行Q型聚类分析。结果表明:133个三角梅品种多个性状多样性丰富,数量性状的变异系数范围为19.61%~32.59%,平均值为26.64%,花序总梗长度、花被管宽度、叶柄长度、花序长度的变异系数最高,多样性指数范围为1.69~2.09,平均值为1.92,叶片长度、苞片宽度、叶片宽度、苞片长度的多样性指数最高。质量性状多样性指数为0.17~2.19,多样性指数大于1的质量性状有11个,苞片颜色、花被管颜色多样性指数均大于2,多样性丰富。4个种系的三角梅品种中,巴特三角梅数量性状的多样性指数最高,多样性最丰富,其次是秘鲁三角梅、光叶三角梅,毛叶三角梅的多样性指数最小,多样性较小,但不同种系各有优势性状。51个性状中,有22个性状在种系之间呈现出了显著差异性,此22个性状对三角梅品种识别和类群划分具有重要的参考价值。根据苞片类型、枝刺多少、叶片大小进行聚类,133个三角梅品种可聚为重瓣少刺、重瓣多刺、单瓣少刺小叶、单瓣多刺大叶4类。上述研究结果显示,供试133个三角梅品种的表型性状多样性较高,数量性状变异类型丰富,本研究可为三角梅种质资源的系统评价、品种分类和种质创新提供参考。

关键词：三角梅变异系数多样性分类指标

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