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Journal of Environmental Sciences 2021年第2期33卷 306-316页

作者： Jie Wan Jiawei Chen Ru Zhao Renxian Zhou Energy Research Institute Nanjing Institute of TechnologyNanjing 211167China Institute of Catalysis Zhejiang UniversityHangzhou 310028China

Series of Fe/Cu-SSZ-13 catalysts with different Fe loading content were synthesized by simple one-pot strategy.The obtained catalysts were subjected to selective catalytic reduction(SCR)of NO x with NH 3 and were characterized by various techniques.The results show that Fe 0.63/Cu 1.50-SSZ-13 catalyst with proper Fe content exhibits excellent catalytic activity with widest operation temperature window from 160 to 580℃,excellent hydrothermal stability as well as good resistance to sulfur poisoning when compared with Cu-SSZ-13,signifying its great potential for practical applications.Further characterizations reveal that the synthesized Fe/Cu-SSZ-13 catalysts present typical chabazite(CHA)structure with good crystallinity,while isolated Cu^2+and monomeric Fe 3+are revealed as the predominant copper and iron species.At low temperatures,isolated Cu^2+species act as primary active sites for SCR reaction,while monomeric Fe^3+species provide sufficient active sites for sustain the SCR activity at high temperature.Moreover,Fe over doping would lead to the damage of zeolite structure,destruction of isolated Cu^2+site,as well as the formation of highly oxidizing Fe2O3,thus causing deterioration of catalytic performances.

关键词： NH3-SCR Fe/Cu-SSZ-13 One-pot synthesis Active species

A method of determining flame radiation fraction induced by interaction burning of tri-symmetric propane fires in open space based on weighted multi-point source model

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Frontiers in Energy 2022年第6期16卷 1017-1026页

作者： jie JI Junrui DUAN Huaxian wan State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230088China

The interaction of multiple fires may lead to a higher flame height and more intense radiation flux than a single fire,which increases the possibility of flame spread and risks to the surroundings.Experiments were conducted using three burners with identical heat release rates(HRRs)and propane as the fuel at various spacings.The results show that flames change from non-merging to merging as the spacing decreases,which result in a complex evolution of flame height and merging point height.To facilitate the analysis,a novel merging criterion based on the dimensionless spacing S/z_(c) was proposed.For non-merging flames(S/z_(c)>0.368),the flame height is almost identical to a single fire;for merging flames(S/z_(c)≤0.368),based on the relationship between thermal buoyancy B and thrust P(the pressure difference between the inside and outside of the flame),a quantitative analysis of the flame height,merging point height,and air entrainment was formed,and the calculated merging flame heights show a good agreement with the measured experimental values.Moreover,the multi-point source model was further improved,and radiation fraction of propane was calculated.The data obtained in this study would play an important role in calculating the external radiation of propane fire.

关键词： flame interaction air entrainment flame height multi-point source model thermal radiation

Amine-catalyzed synthesis of N^(2)-sulfonyl 1,2,3-triazole in water and the tunable N^(2)-H 1,2,3-triazole synthesis in DMSO via metal-free enamine annulation

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Chinese Chemical Letters 2022年第2期33卷 855-858页

作者： Yanhui Guo Yunyun Liu jie-Ping wan College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

The selective synthesis of N^(2)-sulfonyl and N^(2)-H 1,2,3-triazoles via organocatalytic annulation of enaminone/enaminoester with sulfonyl azide has been realized. The unconventional selectivity providing N^(2)-sulfoyl 1,2,3-triazoles takes place in pure water, wherein the hydrogen bond effect between water and the intermediate resulting from enamine-azide corporation accounts for the novel reaction selectivity. On the other hand, the reactions conducted in DMSO specifically afford N^(2)-H 1,2,3-triazoles in the absence of such hydrogen bond effect.

关键词： Enaminone Annulation N^(2)-sulfonyl 1,2,3-triazole Selectivity Green synthesis Sulfonyl azide

Advances in the Transition Metal-Free C—H Trifluoromethylation

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Chinese Journal of Chemistry 2022年第21期40卷 2582-2594页

作者： Demao Chen Jianwen Jiang jie-Ping wan Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchangJiangxi 330022China.

Trifluoromethyl group is one of the most frequently available and promising functional groups in pharmaceutical,agrochemical as well as material molecules.Developing synthetic methods for the synthesis of trifluoromethyl functionalized compounds by trifluoromethylation reactions occupies significant position in modern organic chemistry.On the other hand,as a typical tool of sustainable synthesis,transition metal-free synthesis possesses unique advantages in atom economy,easy product purification as well as excellent eco-tolerance.Consequently,transition metal-free trifluoromethylation reactions constitute the most important approaches for accessing trifluoromethylated molecules.Herein,the advances in the transition metal-free C—H trifluoromethylation reactions are reviewed for the first time.According to the updated state-of-art,both the catalytic reactions by conventional heating chemistry and the more sustainable photocatalysis are included,covering the trifluoromethylation reactions of C(sp^(3))–H bond,aromatic C(sp^(2))–H bond as well as the non-aromatic C(sp^(2))–H bond in different substrates over the last five years(2017—2021).

关键词： C-H bond Trifluoromethylation Transition metal-free Thermochemistry Photocatalysis

A new three-term spectral conjugate gradient algorithm with higher numerical performance for solving large scale optimization problems based on Quasi-Newton equation

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International Journal of Modeling, Simulation, and Scientific Computing 2021年第5期12卷 234-247页

作者： jie Guo Zhong wan School of Mathematics and Statistics Central South University Hunan ChangshaP.R.China

A new spectral three-term conjugate gradient algorithm in virtue of the Quasi-Newton equation is developed for solving large-scale unconstrained optimization problems.It is proved that the search directions in this algorithm always satisfy a sufficiently descent condition independent of any line search.Global convergence is established for general objective functions if the strong Wolfe line search is used.Numerical experiments are employed to show its high numerical performance in solving large-scale optimization problems.Particularly,the developed algorithm is implemented to solve the 100 benchmark test problems from CUTE with different sizes from 1000 to 10,000,in comparison with some similar ones in the literature.The numerical results demonstrate that our algorithm outperforms the state-of-the-art ones in terms of less CPU time,less number of iteration or less number of function evaluation.

关键词： High performance computing optimization algorithm conjugate gradient method convergence analysis

A micelle-based stage-by-stage impelled system for efficient doxorubicin delivery

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Bioactive Materials 2023年第7期25卷 783-795页

作者： Sunfan Li Fangzhou Li Dong wan Zuqin Chen jie Pan Xing-jie Liang School of Chemical Engineering and Technology Tiangong UniversityTianjin300387PR China CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology of ChinaNo.11First North RoadZhongguancunBeijing100190PR China University of Chinese Academy of Sciences Beijing100049PR China Medical School of Chinese PLA No.28 Fuxing RoadBeijing100853PR China Department of Radiology The First Medical CentreChinese PLA General HospitalBeijingPR China Department of Radiology Chinese PAP Guangxi Corps HospitalNanningGuangxiPR China

Chemotherapy remains the mainstay of cancer treatment,benefiting millions of patients each year,but the side effects of chemotherapy drugs severely limit their clinical use.Doxorubicin(DOX)can cause various side effects such as heart damage and treatment-related tumors.The effective use of active and passive targeting will improve the clinical application of DOX.Here,TPGS3350 and bioactive peptides were utilized to construct a micelle-based stage-by-stage impelled efficient system(missiles)for DOX delivery(DOX missiles).By taking advantage of the EPR effect,DOX missiles are efficiently enriched at the tumor site.After being cleaved by matrix metalloproteinase2(MMP2),the peptide(VRGD)targets tumor cells to facilitate uptake of the missiles by the tumor cells via receptor-mediated endocytosis.The intracellular activated caspase-3-catalyzed explosion of DOX missiles further enables efficient tumor killing.This study provides an efficient approach for DOX delivery and toxicity reduction.

关键词： Doxorubicin Delivery Peptide Missiles Chemotherapy

Modeling effect of cooling conditions on solidification process during thermal cycle of rollers in twin-roll strip casting

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Journal of Iron and Steel Research(International) 2023年第1期30卷 64-73页

作者： Chun-feng Bai Bo wang jie Ma jie-yu Zhang wan-ping Pan State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200072China School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Anhui Jianzhu University Hefei 230601AnhuiChina

In the twin-roll strip casting process,molten steel solidifies by losing heat through its interface with the casting rollers.The heat extraction along this interface has an effect on the quality of the strips and should be affected by coating,rolls’material,and cooling water flow rate.It is necessary to understand the effect of these casting parameters on the solidification structure of twin-roll strip casting.A three-dimensional computational domain is set up to simulate the solidification process of molten steel and heat exchange between steel strip/air,coating,rolls,and cooling water in the channel of roll sleeves.The effect of the cooling water intensity and flow intensity of molten steel in the pool on the solidification structures is studied during the thermal cycle of rolls in the twin-roll strip casting.These predicted results are helpful to optimize casting parameters and improve the strip quality in the twin-roll strip casting process.

关键词： Twin-roll strip casting Solidification structure Numerical simulation Thermal cycle Cellular automata finite element model

Role of Mitophagy in Myocardial Ischemia/Reperfusion Injury and Chinese Medicine Treatment

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Chinese Journal of Integrative Medicine 2023年第1期29卷 81-88页

作者： XIA Jun-yan CHEN Cong LIN Qian CUI jie wan jie LI Yan LI Dong Department of Cardiology Dongfang Hospitalthe Second Affiliated Hospital of Beijing University of Chinese MedicineBeijing100078China Department of Cardiology Dongzhimen Hospitalthe First Affiliated Hospital of Beijing University of Chinese MedicineBeijing100007China

Mitophagy is one of the important targets for the prevention and treatment of myocardial ischemia/reperfusion injury(MIRI).Moderate mitophagy can remove damaged mitochondria,inhibit excessive reactive oxygen species accumulation,and protect mitochondria from damage.However,excessive enhancement of mitophagy greatly reduces adenosine triphosphate production and energy supply for cell survival,and aggravates cell death.How dysfunctional mitochondria are selectively recognized and engulfed is related to the interaction of adaptors on the mitochondrial membrane,which mainly include phosphatase and tensin homolog deleted on chromosome ten(PTEN)-induced kinase 1/Parkin,hypoxia-inducible factor-1α/Bcl-2 and adenovirus e1b19k Da interacting protein 3,FUN-14 domain containing protein 1 receptor-mediated mitophagy pathway and so on.In this review,the authors briefly summarize the main pathways currently studied on mitophagy and the relationship between mitophagy and MIRI,and incorporate and analyze research data on prevention and treatment of MIRI with Chinese medicine,thereby provide relevant theoretical basis and treatment ideas for clinical prevention of MIRI.

关键词： mitophagy myocardial ischemia/reperfusion injury PTEN-induced kinase 1/Parkin hypoxia-inducible factor-1α/Bcl-2 and adenovirus e1b19k Da interacting protein 3 FUN-14 domain containing protein 1 Chinese medicine

Stability analysis of linear/nonlinear switching active disturbance rejection control based MIMO continuous systems

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Journal of Systems Engineering and Electronics 2021年第4期32卷 956-970页

作者： wan Hui QI Xiaohui LI jie Department of Unmanned Aerial Vehicle Engineering Army Engineering University of PLAShijiazhuang 050003China The 32nd Research Institute China Electronics Technology Group CorporationShanghai 201800China

In this paper,a linear/nonlinear switching active disturbance rejection control(SADRC)based decoupling control approach is proposed to deal with some difficult control problems in a class of multi-input multi-output(MIMO)systems such as multi-variables,disturbances,and coupling,etc.Firstly,the structure and parameter tuning method of SADRC is introduced into this paper.Followed on this,virtual control variables are adopted into the MIMO systems,making the systems decoupled.Then the SADRC controller is designed for every subsystem.After this,a stability analyzed method via the Lyapunov function is proposed for the whole system.Finally,some simulations are presented to demonstrate the anti-disturbance and robustness of SADRC,and results show SADRC has a potential applications in engineering practice.

关键词： linear/nonlinear switching active disturbance rejection control(SADRC) multi-input multi-output(MIMO)continuous system decoupling control stability analysis

Correlation analysis between underwater noise and Liutex for DTMB4119 propeller

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Journal of Hydrodynamics 2022年第4期34卷 585-595页

作者： Lian-jie Yu Jian-wei Wu De-cheng wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Wuhan Second Ship Design and Research Institute Wuhan 430205China

Propeller is an important equipment of ocean structures.It has characteristics of complex geometry and periodic vortex shed,which means high research value.This paper takes DTMB419 propeller as the research object.A detailed study is conducted on the wake vortices in non-cavitation state and cavitation state.Three vortex identification methods are used to compare the vortices capture effects from downstream sections and three-dimensional perspectives.The results show that,the third-generation vortex identification technologyΩ_(R)shows obvious advantages.At the same time,FW-H equation is used to predict propeller noise,and the relationship between nonlinear sound source distribution and vortices distribution is analyzed.It is found that the distribution of Lighthill tensor is consistent withΩ_(R),which proves the advantages and potential of third-generation vortex identification technology from acoustic perspective.

关键词： Third-generation vortex DTMB4119 propeller cavitation FW-H formulation