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Remote substituent effects on catalytic activity of metal-organic frameworks: a linker orbital energy model

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npj Computational Materials 2023年第1期9卷 1747-1755页

作者： Zhenzhen Wang Huan Meng Xuejiao j.gao jia-jia Zheng Xingfa gao Laboratory of Theoretical and Computational Nanoscience National Center for Nanoscience and Technology of ChinaBeijingChina CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Technology of ChinaBeijingChina College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchangChina

The Hammett equation is commonly used to theoretically depict the remote electronic effects of substituents on catalytic activitiesof metal nodes of metal-organic frameworks (MOFs). However, the application of the theory to MOF catalysts usually encountersproblems because it relies heavily on empirical parameters with unknown transferability. To develop an alternative predictiontheory, the linker orbital energy model has been proposed by density functional theory calculations. The model provides a simplemethod to approximately depict the remote electronic substituent effects on catalytic activities of metal nodes of MOFs, and itsgeneral applicability to MOFs is supported by extensively revisiting the structure-activity relationships reported in the *** model can be used to design catalytic activity of metal nodes of MOFs by engineering the electronic properties of linkers andsubstituents.

关键词： substituent catalytic orbital

Developing a Knock Predictive Criterion in Spark Ignition Engines Fuelled with Gaseous Fuels

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journal of Thermal Science 1993年第4期2卷 304-311页

作者： G.A.Karim j.gao Department of Mechanical Engineering The University of Calgary

Consideration of the chemical reaction activity of the end gas in a spark ignition and operating conditions are combined to predict the onset of knock and associated performance in an engine fuelled with methane.A two-zone predictive combustion model was developed based on an estimate of the efiFective duration of the combustion period and the mass burning rate for any set of operating *** unburned end gas preignition chemical reaction activity is described by a detailed chemical reaction kinetic scheme for methane and *** variation with time of the value of a formulated dimensionless knock parameter(k)is *** is shown that whenever knocking is encountered,the value of'k' builds up to a sufficiently high value that exceeds a critical *** normal operating conditions, the value of'k'remains throughout the whole combustion period at comparatively very low levels. It is shown that the model and the use of this knock criterion'k'produce results that are in good agreement with experiment.

关键词： gas spark ignition knock predictive model knock parameter

Largeπ-conjugated indium-based metal-organic frameworks for high‐performance electrochemical conversion of CO_(2)

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Nano Research 2023年第7期16卷 8743-8750页

作者： Zengqiang gao Yue Gong Yating Zhu junjie Li Li Li Yongxia Shi Man Hou Xuejiao j.gao Zhicheng Zhang Wenping Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic SciencesTianjin UniversityTianjin 300072China College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

The active site engineering of electrocatalysts,as one of the most economical and technological approaches,is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO_(2)reduction ***,an indium-based porphyrin framework(In-TCPP)with a well-defined structure,highly dispersed catalytic center,and good stability was constructed for efficient CO_(2)-to-formate ***-TCPP could achieve a high Faraday efficiency for formate(90%)and a cathodic energy efficiency of 63.8%in flow *** situ attenuated total reflectance Fourier transform infrared spectroscopy and density functional theory calculation confirm that the crucial intermediate is*COOH species which contributes to the formation of *** work is expected to provide novel insights into the precise design of active sites for high-performance electrocatalysts towards electrochemical CO_(2)reduction reaction.

关键词： electrochemical CO_(2)reduction metal-organic framework porphyrin indium formate

The Synergistic Effect of Endohedral Metal and Chemical Multi-addition on the Stability of Fullerene

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The Synergistic Effect of Endohedral Metal and Chemical Mult...

Confined interface engineering of self-supported Cu@N-doped graphene for electrocatalytic CO_(2) reduction with enhanced selectivity towards ethanol

中国化学会第八届全国物理无机化学学术会议

作者： Xuejiao j.gao Xingfa gao College of Chemistry and Chemical Engineering Jiangxi Normal University

Fullerenes are the third allotrope of carbon besides graphite and *** are cage-like molecules which are only constructed by *** inner cavities of fullerenes have diameters of about 1 nm, which allow fullerene to encapsulate metal or metal cluster forming endohedral metallofullerenes(EMFs).Fullerenes and EMFs are promising nanomaterials with potential applications in biomedical, photo sensor, solar cell and etc.

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Nano Research 2022年第10期15卷 8872-8879页

作者： Dejin Zang Xuejiao jgao Leyun Li Yongge Wei Haiqing Wang Institute of Materia Medica Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250117China Institute for Advanced Interdisciplinary Research(iAIR) School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Key Lab of Organic Optoelectronics&Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China

Electroreduction of greenhouse gas CO_(2) into value-added fuels and chemicals provides a promising pathway to address the issues of energy crisis and environmental ***,the regulations of the selectivity towards C2 product and the competing hydrogen evolution reaction(HER)are major challenges for CO_(2) reduction reaction(CO_(2)RR).Here,we develop an interface-enhanced strategy by depositing a thin layer of nitrogen-doped graphene(N-G)on a Cu foam surface(Cu-N-G)to selectively promote the ethanol pathway in CO_(2)*** to the undetectable ethanol selectivity of pure Cu and Cu@graphene(Cu-G),Cu-N-G has boosted the ethanol selectivity to 33.1%in total Faradic efficiency(FE)at−0.8 V *** hydrogen electrode(RHE).The experimental and density functional theory(DFT)results verify that the interconnected graphene coating can not only serve as the fast charge transport channel but also provide confined nanospace for mass *** N doping can not only trigger the intrinsic interaction between N in N-G and CO_(2) molecule for enriching the local concentration of reactants but also promote the average valence state of Cu for C–C coupling *** confinement effect at the interface of Cu-N-G can not only provide high adsorbed hydrogen(Had)coverage but also stabilize the key*HCCHOH intermediate towards ethanol *** provided interface-enhanced strategy herein is expected to inspire the design of Cubased CO_(2)RR electrocatalysts towards multi-carbon products.

关键词： CO_(2)reduction Cu-based catalyst Cu/N-doped carbon interface engineering C2 production

Site-Specific Conjugation of Cell Wall Polyrhamnose to Protein SpyAD Envisioning a Safe Universal Group A Streptococcal Vaccine

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Infectious Microbes & Diseases 2021年第2期3卷 87-100页

作者： Nina j.gao Satoshi Uchiyama Lucy Pill Samira Dahesh joshua Olson Leslie Bautista Shilpa Maroju Aym Berges janet ZLiu Raymond HZurich Nina Mvan Sorge jeff Fairman Neeraj Kapoor Victor Nizet Division of Host-Microbe Systems and Therapeutics Department of PediatricsUC San DiegoLa JollaCaliforniaUSA Vaxcyte Inc.Foster CityCaliforniaUSA Department of Medical Microbiology and Infection Prevention Amsterdam University Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands Netherlands Reference Laboratory for Bacterial Meningitis Amsterdam University Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands Skaggs School of Pharmacy and Pharmaceutical Sciences UC San DiegoLa JollaCaliforniaUSA

Development of an effective vaccine against the leading human bacterial pathogen group A Streptococcus(GAS)is a public health *** species defining group A cell wall carbohydrate(GAC,Lancefield antigen)can be engineered to remove its immunodominant N-acetylglucosamine(GlcNAc)side chain,implicated in provoking autoimmune cross-reactivity in rheumatic heart disease,leaving its polyrhamnose core(GACPR).Here we generate a novel protein conjugate of the GACPR and test the utility of this conjugate antigen in active *** of conjugation to a standard carrier protein,we selected SpyAD,a highly conserved GAS surface protein containing both B-cell and T-cell epitopes relevant to the bacterium that itself shows promise as a vaccine *** was synthesized using the XpressTM cell-free protein expression system,incorporating a non-natural amino acid to which GACpr was conjugated by site-specific click chemistry to yield high molecular mass SpyAD-GACPR conjugates and avoid disruption of important T-cell and B-cell immunological *** conjugated SpyAD-GACPR elicited antibodies that bound the surface of multiple GAS strains of diverse M types and promoted opsonophagocytic killing by human *** immunization of mice with a multivalent vaccine consisting of SpyAD-GACPR,together with candidate vaccine antigens streptolysin O and C5a peptidase,protected against GAS challenge in a systemic infection model and localized skin infection model,without evidence of cross reactivity to human heart or brain tissue *** general approach may allow GAC to be safely and effectively included in future GAS subunit vaccine formulations with the goal of broad protection without autoreactivity.

关键词： group A Streptococcus Streptococcus pyogenes group A carbohydrate Lancefield antigen conjugate vaccine XpressCFTM non-natural amino acids SpyAD Introduction

Modification of optical and electrical properties of sol-gel-derived TiO2-doped ZrO2 gate dielectrics by annealing temperature

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Modification of optical and electrical properties of sol-gel...

Bimetallic phthalocyanine heterostructure used for highly selective electrocatalytic CO_(2) reduction

安徽省第四届（2016年）“卓凌杯”真空科技青年创新大赛暨学术研讨会

作者： D.Q.Xiao G.He j.gao j.G.Lv Z.Q.Sun School of physics and Materials Science Radiation Detection Materials & Devices Lab Anhui University School of Sciences Anhui University of Science and Technology Department of Physics and Electronic Engineering Hefei Normal University

In this letter, annealing temperature dependence on the structure, band gap energy and electrical properties of TiO doped ZrO gate dielectrics deposited by sol-gel method at low temperature were systemically investigated. The crystalline temperature of TiO doped ZrO is up to 600 o C. The transmittance and band gap value of the ZrTiO film were about 75% and 4.0 e V,respectively. 300 o C-annealed ZrTiO MOS capacitor with high dielectric constant of 34.9, a small hysteresis value of 0.004 and low leakage current density of 2.7×10 A/cm were obtained. The dominant conduction mechanisms of Al/ZrTiO/n-Si MOS structures were schottky emission and ohmic conduction in the low electric field and direct tunneling in the high electric field. As a result,it can be concluded that sol-gel derived ZrTiO gate dielectric displays potential application as is a promising candidate in future MOS electronic devices.

关键词： High-k gate dielectrics Optical constant Electrical properties Ti incorporation Sol-gel Conduction mechanisms

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Science China Materials 2022年第1期65卷 155-162页

作者： Chenhuai Yang Zengqiang gao Dingjia Wang Shuyu Li junjun Li Yating Zhu Haiqing Wang Wenjuan Yang Xuejiao j.gao Zhicheng Zhang Wenping Hu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong Institute for Advanced Interdisciplinary Research(iAIR)University of JinanJinan 250022China SZU-NUS Collaborative Innovation Centre for Optoelectronic Science&Technology International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of EducationInstitute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China

Heterogeneous molecular catalysts,such as metal phthalocyanines,are efficient electrocatalysts for CO_(2) reduction reaction(CO_(2)RR).However,the rational design and synthesis of a molecular catalyst-based heterostructure for CO_(2)RR remains ***,we developed a crystalline bimetallic phthalocyanine heterostructure electrocatalyst(CoPc/FePc HS),which achieved an excellent CO_(2)-to-CO conversion efficiency(99%)and outstanding long-term stability after 10 h of *** functional theory calculations revealed that the enhancement of CO_(2)RR performance could be attributed to the distinct electron transfer pattern between FePc and *** heterostructural engineering in molecular catalysts would inspire a unique approach for improving CO_(2)RR performance.

关键词： molecular catalyst phthalocyanine heterostructure CO_(2)reduction electronic effect

Molecular“Coupled Butterfly”on Ag(110):Experiment and First-principles Calculations

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Molecular“Coupled Butterfly”on Ag(110):Experiment and Firs...