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In situ modification of heavy oil catalyzed by nanosized metal-organic framework at mild temperature and its mechanism

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Chinese Journal of Chemical Engineering 2024年第3期67卷 166-173页

作者： Li Wang Ji-Xiang Guo Rui-Ying Xiong Chen-Hao Gao xiao-Jun Zhang Dan luo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing 102200China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China

Two catalysts, nano-sized cobalt-metal-organic framework(Co-MOF) and nickel(Ni)-MOF, were successfully prepared by the modification method. Tetralin(C10H12) was used as the hydrogen donor for the catalytic cracking and hydrogenation modification study of the dehydrated crude oil from the Shengli Oilfield. The optimal reaction conditions were determined through orthogonal experiments, and the components of the crude oil and modified oil samples were analyzed. The results revealed that the nanoMOF catalysts were successfully prepared and exhibited high catalytic activity. They could catalyze the cracking of large molecules in heavy oil at mild temperatures(<300°C), leading to the decomposition of the hydrogen donor. When the mass fraction of the catalyst was 0.2%, the mass fraction of the hydrogen donor was 1%, and the reaction temperature was 280°C, the Ni-MOF showed the best catalytic viscosity reduction effect. It could reduce the viscosity of heavy oil at 50°C from 15761.9 m Pa.s to 1266.2 m Pa.s,with a viscosity reduction rate of 91.97%. The modification effect of Co-MOF was the next best, which could reduce the viscosity of heavy oil to 2500.1 m Pa.s with a viscosity reduction rate of 84.14%. Molecular dynamics simulations revealed a strong interaction force between the MOF surface and asphaltene molecules. In the process of heavy-oil catalytic hydrogenation, the nano-MOF catalyst exhibited high catalytic activity. On the one hand, the empty d orbitals outside the metal atoms in the catalyst could polarize the carbon atoms in the organic matter, accelerating the breaking of long chains. On the other hand, the metal atoms in the catalyst could bond with the carbon σ bonds, breaking the carbon-carbon bonds. This disrupted the structure of the recombined components in the crude oil, irreversibly reducing the viscosity of the heavy oil and improving its fluidity.

关键词： Nano-sized MOF Petroleum Viscosity reduction Catalyst Nanomaterials

Recent advances in electrocatalytic generation of indole-derived radical cations and their applications in organic synthesis

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Chinese Chemical Letters 2024年第4期35卷 106-123页

作者： Wei Zhou Xi Chen Lin Lu Xian-Rong Song Mu-Jia luo Qiang xiao Key Laboratory of Organic Chemistry of Jiangxi Province Jiangxi Science&Technology Normal UniversityNanchang 330013China

Indole-derived radical cations, open-shell reactive species, display distinctive dual reactivity due to the carbon-centered radical and more electrophilic carbocation, which frequently appear in a variety of single electron oxidation reactions for synthesizing structurally diverse functionalized indoles and indolines. Electrocatalysis is considered as a synthetically attractive and environmentally friendly alternative for driving the single electron oxidation of indoles. Remarkable achievements in electrocatalytic indolederived radical cation-mediated indole functionalization have been realized so far. This review comprehensively summarizes the recent progresses in the applications of electrocatalytic indole radical cations,including C(sp~2)–H functionalization, dearomative 2,3-difunctionalization, and ring-opening reaction, emphasizing the vital single electron oxidation steps of indoles, the substrates scope and limitations, and the reaction mechanisms.

关键词： Electrocatalysis Indole radical cation C-H functionalizatin Dearomative 2 3-difunctionalization

On the Shallowing of Antarctic Low-Level Temperature Inversions Projected by CESM-LE under RCP8.5

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Journal of Meteorological Research 2024年第3期38卷 586-599页

作者： Minghu DING Lin ZHANG Tingfeng DOU Yi huanG Yingyan luo Junmei LYU Cunde xiao State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Key Laboratory of Meteorology and Ecological Environment of Hebei Province Hebei Provincial Institute of Meteorological SciencesShijiazhuang050021China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China

Temperature inversions are frequently observed in the boundary layer and lower troposphere of polar *** variations of the low-level temperature inversions in these regions,especially the Antarctic,are still poorly *** to the scarcity of observations in the Antarctic,reanalysis data and numerical simulations are often used in the study of Antarctic climate *** on ERA-Interim,ERA5,JRA-55,and NCEP-NCAR reanalysis products,this study examines temporal and spatial variations of Antarctic inversion depth in austral autumn and winter during *** inversions are found to occur over the high plateau areas of the Antarctic *** on the Mann-Kendall test,ERA-Interim and ERA5 data reveal that the Antarctic inversion depth in austral autumn and winter increased during 1992-2007,roughly maintained afterwards,and then significantly decreased since around *** decrease trend is more obvious in the last two months of ***,JRA-55 better represents the spatial distribution of inversion depth,and ERA-Interim has better interannual *** Community Earth System Model Large Ensemble(CESM-LE)30-member simulations in 1979-2005 were first verified against JRA-55,showing reasonable consistency,and were then used to project the future changes of Antarctic low-level inversion depth over 2031-2050 under *** CESM-LE projection results reveal that the temperature inversion will shallow in the Antarctic at the end of the 21st century,and the decrease in depth in autumn will be more pronounced than that in *** particular,the temperature inversion will weaken over the ice-free ocean,while it will remain stable over the ice sheet,showing certain spatial heterogeneity and seasonal dependence on the underlying cryospheric surface *** addition,the decrease of inversion depth is found closely linked with the reduction in sea ice,suggesting the strong effect of global warming on the thermal structure change o

关键词： boundary layer temperature inversion Antarctic climate change Community Earth System Model Large Ensemble(CESM-LE)

Current therapies for osteoarthritis and prospects of CRISPR-based genome,epigenome,and RNA editing in osteoarthritis treatment

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Journal of Genetics and Genomics 2024年第2期51卷 159-183页

作者： Yuxi Chen xiao luo Rui Kang Kaixin Cui Jianping Ou Xiya Zhang Puping Liang MOE Key Laboratory of Gene Function and Regulation State Key Laboratory of BiocontrolSchool of Life SciencesSun Yat-sen UniversityGuangzhouGuangdong 510275China Center for Reproductive Medicine The Third Affiliated Hospital of Sun Yat-sen UniversitySun Yat-sen UniversityGuangzhouGuangdong 510630China

Osteoarthritis(OA)is one of the most common degenerative joint diseases worldwide,causing pain,disability,and decreased quality of *** balance between regeneration and inflammation-induced degradation results in multiple etiologies and complex pathogenesis of ***,there is a lack of effective therapeutic strategies for OA *** the development of CRISPR-based genome,epigenome,and RNA editing tools,OA treatment has been improved by targeting genetic risk factors,activating chondrogenic elements,and modulating inflammatory *** by cell therapy and in vivo delivery vectors,genome,epigenome,and RNA editing tools may provide a promising approach for personalized OA *** review summarizes CRISPR-based genome,epigenome,and RNA editing tools that can be applied to the treatment of OA and provides insights into the development of CRISPR-based therapeutics for OA ***,in-depth evaluations of the efficacy and safety of these tools in human OA treatment are needed.

关键词： Osteoarthritis Genome editing Epigenone editing RNA editing

Mobile-ionic FETs with ultra-scaled amorphous dielectric achieving ferroelectric behaviors and sub-kT/q swing with temperature down to 77 K

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Science China(Information Sciences) 2024年第1期67卷 312-313页

作者： huan LIU Qiyu YANG Chengji JIN Jiajia CHEN Lulu CHOU xiao YU Yan LIU Genquan HAN Research Center for Intelligent Chips School of Microelectronics Xidian University

The steep subthreshold swing (SS) could be achieved in negative capacitance field-effect transistors (NCFET) to reduce power dissipation in modern electronics. Polycrystalline Hf O2-based ferroelectric materials have attracted great interest due to their better thickness scalability and CMOS process compatibility [1].

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Principal Model Analysis Based on Bagging PLS and PCA and Its Application in Financial Statement Fraud

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Journal of Systems Science and Information 2024年第2期12卷 212-228页

作者： xiao LIANG Qiwei XIE Chunyan luo Liang TANG Yi SUN School of Economics and Management Beijing University of TechnologyBeijing 100124China Shanghai Tongtu Semiconductor Technology Co. LtdShanghai 210203China School of Finance Anhui University of Finance&EconomicsBengbu 233000China

Motivated by the Bagging Partial Least Squares(Bagging PLS)and Principal Component Analysis(PCA)algorithms,a novel approach known as Principal Model Analysis(PMA)method is introduced in this *** the proposed PMA algorithm,the PCA and the Bagging PLS are *** this method,multiple PLS models are trained on sub-training sets,derived from the training set using the random sampling with replacement *** regression coefficients of all the sub-PLS models are fused in a joint regression coefficient *** final projection direction is then estimated by performing the PCA on the joint regression coefficient ***,the proposed PMA method is compared with other traditional dimension reduction methods,such as PLS,Bagging PLS,Linear discriminant analysis(LDA)and *** results on six public datasets demonstrate that our proposed method consistently outperforms other approaches in terms of classification performance and exhibits greater ***,it is employed in the application of financial statement fraud *** and other five algorithms are utilized to financial statement fraud which concerned by the academic community,and the results indicate that the classification of PMA surpassed that of the other methods.

关键词： principal model analysis partial least squares principal component analysis dimension reduction ensemble learning financial statement fraud detection

Barley Protein LFBEP-C1 from Lactiplantibacillus plantarum dy-1 Fermented Barley Extracts by Inhibiting Lipid Accumulation in a Caenorhabditis elegans Model

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Biomedical and Environmental Sciences 2024年第4期37卷 377-386页

作者： ZHANG Jia Yan LIU Meng Ting LIU Yu Hao DENG huan BAI Juan XIE Jian Hua xiao Xiang School of Food and Biological Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina State Key Laboratory of Food Science and Technology Nanchang UniversityNanchang 330047JiangxiChina

Objective This study aimed to investigate the lipid-lowering activity of LFBEP-C1 in high glucose-fed Caenorhabditis elegans(***).Methods In this study,the fermented barley protein LFBEP-C1 was prepared and tested for its potential anti-obesity effects on *** worms were fed Escherichia coli OP50(*** OP50),glucose,and different concentrations of *** size,lifespan,movement,triglyceride content,and gene expression were *** results were analyzed using ANOVA and Tukey's multiple comparison *** Compared with the model group,the head-swing frequency of *** in the group of LFBEP-C1 at 20μg/mL increased by 33.88%,and the body-bending frequency increased by 27.09%.This indicated that LFBEP-C1 improved the locomotive ability of *** average lifespan of *** reached 13.55 days,and the body length and width of the *** decreased after LFBEP-C1 ***,LFBEP-C1 reduced the content of lipid accumulation and triglyceride *** expression levels of sbp-1,daf-2,and mdt-15 significantly decreased,while those of daf-16,tph-1,mod-1,and ser-4 significantly increased after LFBEP-C1 *** in these genes explain the signaling pathways that regulate lipid *** LFBEP-C1 significantly reduced lipid deposition in *** fed a high-glucose diet and alleviated the adverse effects of a high-glucose diet on the development,lifespan,and exercise behavior of *** addition,LFBEP-C1 regulated lipid metabolism mainly by mediating the expression of genes in the sterol regulatory element-binding protein,insulin,and 5-hydroxytryptamine signaling pathways.

关键词： LFBEP-C1 Fermentation Protein Caenorhabditis elegans Lipid accumulation Signaling pathway

Introducing sulfur to nickel-iron selenide for high-efficiency alkaline seawater electrolysis

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Science China Chemistry 2024年第8期67卷 2747-2754页

作者： Xuanwa Chen Yanhui Yu Xingqi Han huan Wang Yingjie Hua Daoxiong Wu Peilin Deng Juanxiu xiao Xinlong Tian Jing Li School of Marine Science and Engineering Hainan Provincial Key Lab of Fine ChemistrySchool of Chemistry and Chemical EngineeringHainan UniversityHaikou 570228China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province School of Chemistry and Chemical EngineeringHainan Normal UniversityHaikou 571158China

Seawater electrolysis is an effective way to obtain hydrogen(H_(2))in a sustainable ***,the lack of electrocatalysts with high activity,stability,and selectivity for oxygen evolution reaction(OER)severely hinders the development of seawater electrolysis ***,sulfur-doped nickel-iron selenide nanosheets(S-NiFeSe_(2))were prepared by an ion-exchange strategy and served as highly active OER electrocatalyst for alkaline seawater *** overpotential is 367 m V,and it can run stably for over 50 h at 100 m A cm^(-2).Excitingly,the S-NiFeSe_(2)||Pt/C pair exhibits cell voltage of 1.54 V at 10 m A cm^(-2)under alkaline seawater conditions,which can run smoothly for 100 h without decay,and the efficiency of electricity-tohydrogen(ETH)energy conversion reaches more than 80%.Such electrode,with abundant accessible reactive sites and good corrosion resistance,is a good candidate for seawater ***,density functional theory calculations reveal that the surface sulfur atoms can activate the adjacent Ni sites and decrease the free energy changes of the associated intermediates at the adjacent Ni sites for OER,and the step of~*OH→~*O is the potential rate-limiting *** this work,the true reactive site in nickel-iron selenides is the Ni sites,but not the Fe sites as commonly believed.

关键词： S-doping nickel-iron selenide electrocatalysts oxygen evolution reaction alkaline seawater electrolysis

Photocatalytic uranium extraction boosted by dual effective active sites of porphyrin metal-organic frameworks

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Nano Research 2024年第7期17卷 6713-6720页

作者： Jianming Pan Bentian xiao Wei Zhu Yanan Yang Hongliang huang Zichao Lian Tao Zhang Fengxian Qiu Songlin Xue huan Pang School of Chemistry and Chemical Engineering Jiangsu University301 Xuefu RoadZhenjiang 212013China Institute of Smart Liquid Crystal Technologies JITRI280 Huangpu Jiang RoadChangshu 215500China State key laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China School of Chemistry and Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou 225002China

Porphyrinoid metal-organic frameworks(MOFs)with dual effective uranium uptake sites were synthesized through combined insitu and post-synthetic *** MOF10@5 demonstrates the uptake amount of uranium reaches 1476 mg/g under visiblelight *** PN-MOF10@5 with dual uranyl uptake sites yields the amount of extracting uranyl of 1590 mg/g under visible-light *** density functional theory(DFT)calculations reveal strong interaction between uranyl and dual uranyl effective active *** MOFs demonstrate a powerful synthesis strategy for uranium extraction materials with dual effective active sites.

关键词： photocatalytic uranium extraction metal-organic framework(MOF) dual active sites in-suit synthesis post-synthetic