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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： Farid Bahari-Sambran Fernando Carre?o C.M.Cepeda-Jiménez Alberto Orozco-Caballero Physical Metallurgy Department CENIM-CSIC Department of Mechanical Engineering Chemistry and Industrial Design Polytechnic University of Madrid

The aim of this work is to predict, for the first time, the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models, random forest（RF） and artificial neural network（ANN）. With that purpose, a ZK30 magnesium alloy was friction stir processed（FSP） using three different severe conditions to obtain fine grain microstructures（with average grain sizes between 2 and 3 μm） prone to extensive superplastic response. The three friction stir processed samples clearly deformed by grain boundary sliding（GBS） deformation mechanism at high temperatures. The maximum elongations to failure, well over 400% at high strain rate of 10-2s-1, were reached at 400 ℃ in the material with coarsest grain size of 2.8 μm, and at 300 ℃ for the finest grain size of 2 μm. Nevertheless, the superplastic response decreased at 350 ℃ and 400 ℃ due to thermal instabilities and grain coarsening, which makes it difficult to assess the operative deformation mechanism at such temperatures. This work highlights that the machine learning models considered, especially the ANN model with higher accuracy in predicting flow stress values, allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artificial intelligence Magnesium alloys Superplasticity Friction stir processing Grain coarsening

In Situ Analysis of Tobacco Leaves Based on Microwave Plasma Torch Desorption Ionization Mass Spectrometry

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Journal of Analysis and Testing 2024年第1期8卷 9-15页

作者： He Tang Yonggang Zhang Zhiguang Reng Junchen Zhu Yue Xie Xiaobin Zhang Hongru Feng Kailong Yuan Yuanjiang Pan Department of chemistry Zhejiang UniversityHangzhou 310027China Zhejiang China Tobacco industrial Co. Ltd.Hangzhou310008China

Tobacco is an important economic crop worldwide.Tobacco leaves contain a large number of natural products.Therefore,the analysis of tobacco composition is crucial for the control of tobacco safety and quality assessment.Microwave plasma torch desorption ionization mass spectrometry(MPT-MS) is an emerging ambient mass spectrometry(AMS) technique that can be used for rapid real-time analysis of s amples without pretreatment.Our work focuses on the chemical composition analysis of tobacco using MPT-MS,and 14 compounds were detected in green flue-cured tobacco leaves,while 30 compounds were detected in cured flue-cured tobacco leaves,which confirms that curing can enhance the flavor of cigarettes.Furthermore,we successfully in situ identified characteristic fragment ions of α/β-CBD(α/β-cembranoids),an important aroma compound in tobacco by MPT-MS.The results demonstrate the capability of MPT-MS for in situ analysis of tobacco components and its potential for evaluating tobacco quality.

关键词： Microwave plasma torch Ambient mass spectrometry Tobacco α/β-Cembranoids

Electrochemical reduction of carbon dioxide to produce formic acid coupled with oxidative conversion of biomass

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Journal of Energy chemistry 2024年第5期92卷 705-729页

作者： Xi Liu Yifan Wang Zhiwei Dai Daihong Gao Xuebing Zhao Key Laboratory of industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Institute of Applied chemistry Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Electrochemical reduction of CO_(2)(CO_(2)RR)has become a research hot spot in recent years in the context of carbon neutrality.HCOOH is one of the most promising products obtained by electrochemical reduction of CO_(2) due to its high energy value as estimated by market price per energy unit and wide application in chemical industry.Biomass is the most abundant renewable resource in the natural world.Coupling biomass oxidative conversion with CO_(2)RR driven by renewable electricity would well achieve carbon negativity.In this work,we comprehensively reviewed the current research progress on CO_(2)RR to produce HCOOH and coupled system for conversion of biomass and its derivatives to produce value-added products.Sn-and Bi-based electrocatalysts are discussed for CO_(2)RR with regards to the structure of the catalyst and reaction mechanisms.Electro-oxidation reactions of biomass derived sugars,alcohols,furan aldehydes and even polymeric components of lignocellulose were reviewed as alternatives to replace oxygen evolution reaction(OER)in the conventional electrolysis process.It was recommended that to further improve the efficiency of the coupled system,future work should be focused on the development of more efficient and stable catalysts,careful design of the electrolytic cells for improving the mass transfer and development of environment-friendly processes for recovering the formed formate and biomass oxidation products.

关键词： Electrochemical reduction of CO_(2) Formic acid Oxidative conversion of biomass Lignocellulose Coupled system

Efficient upcycling of high-density polyethylene into separable cyclic hydrocarbons

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Science China chemistry 2024年第4期67卷 1049-1050页

作者： Shenglu Lu Yanqin Wang State key laboratory of green chemical engineering and industrial catalysis Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

This highlight is inspired by a recent article in Nature Nanotechnology in which Zeng and co-workers[1]from the University of Science and Technology of China reported a strategy for upcycling high-density polyethylene(HDPE)into separable cyclic hydrocarbons under solvent-and hydrogen-free condition.This work made a significant progress in plastic recycling.

关键词： hydrocarbons cycling high

Enhanced electrocatalytic CO_(2)reduction to formic acid using nanocomposites of In_(2)O_(3)@C with graphene

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Nano Research 2024年第6期17卷 5031-5039页

作者： Wenxiang Li Shuo Gao Chuanruo Yang Juntao Yang Amjad Nisar Guolei Xiang Junsu Jin Beijing Key Laboratory of Membrane Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Nanomaterials Research Group PDPINSTECHIslamabad 44000Pakistan Institute of industrial chemistry College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China

In_(2)O_(3)is an effective electrocatalyst to convert CO_(2)to formic acid(HCOOH),but its inherent poor electrical conductivity limits the efficient charge transfer during the reaction.Additionally,the tendency of In_(2)O_(3)particles to agglomerate during synthesis further limits the exposure of active sites.Here we address these issues by leveraging the template effect of graphene oxide and employing InBDC as a self-sacrificing template for the pyrolysis synthesis of In_(2)O_(3)@C.The resulting In_(2)O_(3)@C/rGO-600 material features In_(2)O_(3)@C nanocubes uniformly anchored on a support of reduced graphene oxide(rGO),significantly enhancing the active sites exposure.The conductive rGO network facilitates charge transfer during electrocatalysis,and the presence of oxygen vacancies generated during pyrolysis,combined with the strong electron-donating ability of rGO,enhances the adsorption and activation of CO_(2).In performance evaluation,In_(2)O_(3)@C/rGO-600 exhibits a remarkable HCOOH Faradaic efficiency exceeding 94.0%over a broad potential window of−0.7 to−1.0 V(vs.reversible hydrogen electrode(RHE)),with the highest value of 97.9%at−0.9 V(vs.RHE)in a H-cell.Moreover,the material demonstrates an excellent cathodic energy efficiency of 71.6%at−0.7 V(vs.RHE).The study underscores the efficacy of uniformly anchoring metal oxide nanoparticles onto rGO for enhancing the electrocatalytic CO_(2)reduction performance of materials.

关键词： In_(2)O_(3)@C nanocomposite electrochemical CO_(2)reduction reduced graphene oxide oxygen vacancy

Combining cisplatin and a STING agonist into one molecule for metalloimmunotherapy of cancer

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National Science Review 2024年第1期11卷 107-119页

作者： Shuren Zhang Dongfan Song Wenhao Yu Ji Li Xiaoyu Wang Yachao Li Zihan Zhao Qi Xue Jing Zhao Jie P.Li Zijian Guo State Key Laboratory of Coordination chemistry School of Chemistry and Chemical EngineeringChemistry and Biomedicine Innovation Center (ChemBIC) Nanjing University Department of Urology Afflliated Drum Tower HospitalMedical SchoolNanjing University Nanchuang (Jiangsu)Institute of chemistry and Health

Mounting evidence suggests that strategies combining DNA-damaging agents and stimulator of interferon genes(STING) agonists are promising cancer therapeutic regimens because they can amplify STING activation and remodel the immunosuppressive tumor microenvironment. However, a single molecular entity comprising both agents has not yet been developed. Herein, we designed two PtIV-MSA-2 conjugates(Ⅰand Ⅱ) containing the DNA-damaging chemotherapeutic drug cisplatin and the innate immuneactivating STING agonist MSA-2; these conjugates showed great potential as multispecific small-molecule drugs against pancreatic cancer. Mechanistic studies revealed that conjugate Ⅰ upregulated the expression of transcripts associated with innate immunity and metabolism in cancer cells, significantly differing from cisplatin and MSA-2. An analysis of the tumor microenvironment demonstrated that conjugate I could enhance the infiltration of natural killer(NK) cells into tumors and promote the activation of T cells, NK cells and dendritic cells in tumor tissues. These findings indicated that conjugate I, which was created by incorporating a Pt chemotherapeutic drug and STING agonist into one molecule, is a promising and potent anticancer drug candidate, opening new avenues for small-molecule-based cancer metalloimmunotherapy.

关键词： platinum drug STING agonist single-molecule multitarget metalloimmunology

Porous garnet as filler of solid polymer electrolytes to enhance the performance of solid-state lithium batteries

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Nano Research 2024年第4期17卷 2663-2670页

作者： Yang Zhang Lei Zhang Peng Guo Chaoyan Zhang Xiaochuan Ren Zhen Jiang Jianjun Song Chuan Shi College of Physics Qingdao UniversityQingdao 266071China industrial Research Institute of Nonwovens and Technical Textiles College of Textiles and ClothingQingdao UniversityQingdao 266071China Department of chemistry University of PennsylvaniaPhiladelphiaPA 19104USA

In order to enhance the ionic conductivity of solid polymer electrolytes(SPEs)and their structural rigidity against lithium dendrite during lithium-ion battery(LIB)cycling,we propose porous garnet Li6.4La3Zr2Al0.2O12(LLZO),as the filler to SPEs.The porous LLZO with interlinked grains was synthesized via a resol-assisted cationic coordinative co-assembly approach.The porous structure of LLZO with high specific surface area facilitates the interaction between polymer and filler and provides sufficient entrance for Li^(+)migration into the LLZO phase.Furthermore,the interconnection of LLZO grains forms continuous inorganic pathways for fast Li^(+)migration,which avoid the multiple diffusion for Li^(+)in interface.As a result,the SPEs with porous LLZO(SPE-PL)show a high ionic conductive of 0.73 mS·cm^(-1) at 30℃ and lithium-ion transference number of 0.40.The porous LLZO with uniformly dispersed pores also acts as an ion distributor to regulate ionic flux.The lithium-symmetrical batteries assembled with SPE-PL show a highly stable Li plating/stripping cycling for nearly 3000 h at 0.1 mA·cm^(-2).The corresponding Li/LiFePO_(4) batteries also exhibit excellent cyclic performance with capacity retention of 75%after nearly 500 cycles.This work brings new insights into the design of conductive fillers and the optimization of SPEs.

关键词： solid polymer electrolytes lithium metal battery porous conductive filler solid state battery

The interaction of the structure-directing agent with the zeolite framework determines germanium distribution in SCM-15 germanosilicate

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 105-114页

作者： Stoyan P.Gramatikov Petko St.Petkov Zhendong Wang Weimin Yang Georgi N.Vayssilov Faculty of chemistry and Pharmacy University of Sofia1126 SofiaBulgaria State Key Laboratory of Green Chemical Engineering and industrial Catalysis Sinopec Shanghai Research Institute of Petrochemical Technology Co.Ltd.Shanghai 201208China

We report results from computational modeling of the relative stability of germanosilicate SCM-15 structure due to different distribution of germanium heteroatoms in the double four-member rings(D4Rs)of the framework and the orientation of the structure directing agent(SDA)molecules in the as-synthesized zeolite.The calculated relative energies of the bare zeolite framework suggest that structures with germanium ions clustered in the same D4Rs,e.g.,with large number of Ge–O-Ge contacts,are the most stable.The simulations of various orientations of the SDA in the pores of the germanosilicate zeolite show different stability order-the most stable models are the structures with germanium spread among all D4Rs.Thus,for SCM-15 the stabilization due to the presence of the SDA and their orientation,is thermodynamic factor directing both the formation of specific framework type and Ge distribution in the framework during the synthesis.The relative stability of bare structures with different germanium distribution is of minor importance.This differs from SCM-14 germanosilicate,reported earlier,for which the stability order is preserved in presence of SDA.Thus,even for zeolites with the same chemical composition and SDA,the characteristics of their framework lead to different energetic preference for germanium distribution.

关键词： zeolite density functional theory structure-directing agent SCM-15

Linker gadolinium as charge channel and singlet oxygen activation site in graphitic carbon nitride for enhancing photocatalytic decomposition of tetracycline

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Journal of Rare Earths 2024年第5期42卷 827-837,I0001页

作者： Jianmin Luo Wenqin Li Xinglei Wang Eric Lichtfouse Donglan Huang Xiaoyuan Chen Yi Zhang Lejie Zhu Chuanyi Wang College of chemistry and Civil Engineering Shaoguan UniversityShaoguan512005China Key Laboratory of Pollutant chemistry and Environmental Treatment College of Chemistry and Environmental ScienceYili Normal UniversityYining 835000China College of chemistry and Environmental Science Kashi UniversityKashi844006China CNRS IRDINRAEColl FranceCEREGEAix-Marseille UniversityAix en Provence13100France Guangzhou Institute of industrial Intelligence(GIl) Guangzhou511400China

Reactive oxygen species are essential in photocatalytic water treatment.In this paper,Gd doped carbon nitride(CN)photocatalysts were prepared by simple thermal polymerization for the photocatalytic degradation of tetracycline under visible light irradiation.The photodegradation rate of *** is as high as 95%in 18 min,and the photocatalytic performance is much higher than that of CN.The improvement of photocatalytic performance is mainly attributed to the fact that Gd ion implantation directly provides active sites for oxygen activation and induces the formation of N vacancies.The results of characterizations show that the introduction of Gd in CN can improve the conversion ability of activated oxygen,carrier separation and energy band structure adjustment.Therefore,1.0GdCN photocatalyst can be employed for efficient photocatalytic synthesis of tetracycline.Furthermore,three ways of photocatalytic degradation of tetracycline were revealed by high performance liquid chromatographymass spectrometry.This work provides insights into the doping strategy of CN to improve the production of reactive oxygen species for environmental remediation.

关键词： Photocatalysis Tetracycline Hydrogen peroxide Gd doped CN Singlet oxygen Rare earths

Engineering the Interface Between Au Nanoparticles and CoO-Ov to Enhance the Catalytic Performance of 5-Hydroxymethylfurfural(HMF)to 2,5-Dimethylfuran(DMF)

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Chemical Research in Chinese Universities 2024年第1期40卷 47-54页

作者： XIANG Shuang GUO Yong LIU Xiaohui WANG Yanqin Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterResearch Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237P.R.China

The interface between Au and support has attracted extensive interest because of its unique catalytic ability for hydrogen activation in catalytic hydrogenation/hydrogenolysis reactions.Herein,we create the Au-CoO-OV interface in the 1.0%Au/Co3O4-Rod-250 catalyst,which could dissociate H2 via the heterolytic way to yield rich hydride species and achieve excellent catalytic performance in the hydrogenolysis of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-dimethylfuran(DMF).The XRD and HRTEM analyses show that Au nanoparticles are uniformly dispersed on CoO-OV surface and in situ DRIFTS spectra show the enhancement of heterolytic dissociation of hydrogen(signals of Au-D and O-D vibration)compared with bare CoO(Co3O4-Rod-250).This work provides insights for fabricating highly active Au-support catalysts for catalytic hydrogenation/hydrogenolysis reactions.

关键词： Au-CoO-OV interface Hydride species Heterolytic dissociation 5-Hydroxymethylfurfural(HMF) 2 5-Dimethylfuran(DMF)