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Bimetallic anchoring catalysis for C–H and C–C activation

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Science China Chemistry 2021年第11期64卷 1923-1937页

作者： Jiang-Fei Li yu-Xin luan Mengchun Ye State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryFrontiers Science Center for New Organic MatterNankai UniversityTianjin300071China

Following the age of directing group,anchoring catalysis starts coming to the center of the *** from the directinggroup strategy that needs a preinstalled directing group in substrates,anchoring catalysis relies on a reversible interaction between a substrate and a catalyst,which then directs metal to activate inert chemical *** reversible directing effect not only generates good site-and stereo-selectivity as traditional directing groups do but also eliminates the requirement of stoichiometric amounts of directing *** variously reported anchoring catalysis,coordinative bimetallic anchoring catalysis in general displays superior reactivity than others because coordinative bonding not only affords strong interaction of catalysts with substrates but also displays good compatibility with substrates and reaction *** recent years,big progress has been achieved for coordinative bimetallic anchoring *** review gave a detailed summary of this field,including catalyst development,catalyst types,reaction types and reaction mechanisms.

关键词： C–H activation C–C activation bimetallic catalysis enantioselective anchoring catalysis

Catalytic Characteristics of Lipase Immobilized in CTAB/TX-100 MBG

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Chemical Research in Chinese Universities 2010年第1期26卷 110-113页

作者： SONG Shao-fang luan yu-xia College of Chemistry and Material Science Shandong Agricultural University Tai ＇an 271018 P. R. China Institute of Pharmaceuties School of Pharmaceutical Science Shandong University Jinan 250100 P. R. China

CTAB/TX-100 microemtdsion-based gel（MBG）, which could be soaked in aqueous solution for a long time without mechanical strength and shape changes, was successfully prepared. Lipase immobilized in this gel had a higher activity than that in CTAB MBG when catalyzed the esterification reaction between n-hexanoic acid and n-octanol and its enantioselectivity was slightly higher when catalyzed the stereoselective esterification reaction between racemic ibuprofen and n-octanol. In aqueous solution, lipase in CTAB/TX-100 MBG could catalyze smoothly the hydrolysis reaction of olive oil and could be reused many times without the evident change of MBG mechanical strength although its activity decreased 41.8% after nine-time recycles.

关键词： Microemulsion-based gel(MBG) Immobilized lipase Activity Stereoselectivity Esterification Hydrolysis

Investigation on thermal characteristics and desensitization mechanism of improved step ladder-structured nitrocellulose

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Defence Technology（防务技术） 2023年第2期20卷 93-102页

作者： Cheng-kai Pu yu luan Ming-jun Yi Zheng-gang Xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094People's Republic of China

Nitrocellulose,or cellulose nitrate,has received considerable interest due to its various applications,such as propellants,coating agents and gas ***,its high mechanical sensitivity caused many accidents during its storage and usage in *** this work,two kinds of insensitive step ladderstructured nitrocellulose(LNC)with different nitrogen contents were *** products were characterized by FT-IR,Raman,XRD,SEM,elemental analysis,TGA,DSC,accelerating rate calorimeter analysis(ARC),and drop weight test to study their molecular structure,thermal characteristics and desensitization *** with raw nitrocellulose,LNC has a sharper exothermic peak in the DSC and ARC *** H50values of the two kinds of LNC increased from 25.76 to 30.01 cm for low nitrogen content and from 18.02 to 21.84 cm for high nitrogen content,*** results show that the ladder-structure of LNC which provides regular molecular arrangement and a soft buffer made with polyethylene glycol could affect the energy releasing process of LNC and reduce the sensitivity of *** LNC provides an alternative to be used as a binder in insensitive propellants formulation.

关键词： Nitrocellulose Decomposition Desensitization Ladder structure Thermal characteristic Polyethylene glycol

Modeling and simulation of solvent behavior and temperature distribution within long stick propellants with large web thickness undergoing drying

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Defence Technology（防务技术） 2023年第10期28卷 42-55页

作者： Enfa Fu Qianling Liu yu luan Yao Zhu Weidong He Zhenggang Xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094People's Republic of China

Drying is a complicated physical process which involves simultaneous heat and mass transfer in the removal of solvents inside *** drying techniques may result in the formation of a hard skin layer near the surface to block the free access of most solvent through for long stick propellants with large web thickness,which lead to lower drying efficiency and worse drying *** study aims to gain a comprehensive understanding of drying process and clarify the mechanism of the blocked layer near the propellant surface.A new three-dimensional coupled heat and mass transfer(3D-CHMT)model was successfully developed under transient *** drying experiment results show that the 3DCHMT model could be applied to describe the drying process well since the relative error of the content of solvent between simulation and experiment values is only 5.5%.The solvent behavior simulation demonstrates that the mass transfer process can be divided into super-fast(SF)and subsequent minorfast(MF)stages,and the SF stage is vital to the prevention of the blocked layer against the free access for solvent molecules inside propellant *** effective solvent diffusion coefficient(Deff)of the propellant surface initially increases from 3.4×10^(-6)to 5.3×10^(-6)m^(2)/s as the temperature increases,and then decreases to 4.1×10^(-8)m^(2)/s at 60-100 *** value of Deffof surface between 0-1.4 mm has a unique trend of change compared with other regions,and it is much lower than that of the internal at100 min under simulation ***,the temperature of the propellant surface increases rapidly at the SF stage(0-100 min)and then very slowly *** the evolution of Deffand temperature distribution demonstrate that the blocked layer near the propellant surface has been formed in the time period of approximately 0-100 min and its thickness is about 1.4 *** mitigate the formation of blocked layer and improve its drying quality of finial prop

关键词： Stick propellants Drying Large web thickness 3D numerical modeling Heat transfer Solvent behavior

Activity and Enantioselectivity of Lipase Immobilized in CTAB Microemulsion-based Gels

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Chemical Research in Chinese Universities 2007年第6期23卷 749-752页

作者： SONG Shao-fang luan yu-xia LU Fu-sui College of Chemistry and Material Science Shandong Agricultural University Taian 271018 P. R. China Institute of Pharmaceutics School of Pharmaceutical Science Shandong University Jinan 250100 P. R. China

Introduction The formation of gelatin-containing mieroemulsionbased gels（MBGs） was first described in 1986 and the physical/structural characterization was carried out by a number of groups with a variety of techniques including tracer diffusion, electrical conductivity, NMR, X-ray and small angle neutron scattering. The MBGs were proposed to comprise an extensive, rigid, interconnected network of gelatin/water rods stabilized by a monolayer of surfactant, in coexistence with a po- pulation of conventional W/O microemulsion droplets.

关键词： Microemulsion-based gels Immobilized lipase Racemic ibuprofen Enantioselectivity Enantiomerie excess

Recommendations for articles and reviews in colorectal cancerrelated research at the year-end of 2023

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World Journal of Gastroenterology 2024年第30期30卷 3548-3553页

作者： Wen-yu luan Hao Lin Yan-Dong Miao Department of Cancer Center The Yantai Affiliated Hospital of Binzhou Medical UniversityThe Second Medical College of Binzhou Medical UniversityYantai 264100Shandong ProvinceChina

As peer reviewers of the World Journal of Gastroenterology,our weekly routine involves immersing ourselves in the newly published issue,particularly focusing on the realm of colorectal cancer(CRC)*** diligently sift through various contributions,ranging from comprehensive reviews to original articles and other scholarly *** meticulous examination,we discern the most notable papers,delving into each with careful scrutiny to distill their merits and ***,this undertaking demands considerable time and ***,it stands as an indispensable pursuit,affording us a profound comprehension of the latest breakthroughs in CRC ***,these meticulously curated selections furnish readers with invaluable resources,serving as enduring references for the nuanced exploration of this dynamic field.

关键词： Colorectal cancer Molecular mechanism Genetic marker Application of new technologies Diagnosis Treatment

High-Temperature Stability of Mg-1Al-12Y Alloy Containing LPSO Phase and Mechanism of Its Portevin-Le Chatelier(PLC)Effect

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 982-998页

作者： Qian-Long Ren Shuai yuan Shi-yu luan Jin-Hui Wang Xiao-Wei Li Xiao-yu Liu Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and FormingQinghai UniversityXining810016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China

In this study,the high-temperature stability and the generation mechanism of the Portevin-Le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusting the content of long-period stacking ordered(LPSO)*** was found that the content of LPSO phases in the alloys differed the most after heat treatment at 530℃for 16 h and 24 h,with values of 13.56%and 3.93%***,high-temperature tensile experiments were conducted on these two alloys at temperatures of 150℃,200℃,250℃,and 300℃.The results showed that both alloys exhibited the PLC effect at temperatures ranging from 150 to 250℃.However,at a temperature 300℃,only the alloy with a greater concentration of LPSO phases exhibited the PLC effect,whereas the alloy with a lower proportion of LPSO phases did not exhibit this ***,both alloys exhibited remarkable high-temperature stability,with the alloy containing a greater percentage of LPSO phases also demonstrating superior *** underlying mechanism for this phenomenon lies in the exceptional high-temperature stability exhibited by the second phase within the ***,the LPSO phase effectively obstructs the movement of dislocations,and it also undergoing kinking to facilitate plastic deformation of the *** results indicate that the PLC effect can be suppressed by reducing dislocation pile-up at grain boundaries,which leads to a decrease in alloy plasticity but an increase in *** presence of the PLC effect in the WA121 alloy is attributed to the abundant dispersed second phase within the alloy,which initially hinders the movement of dislocations,leading to an increase in stress,and subsequently releases the dislocations,allowing them to continue their movement and thereby reducing in stress.

关键词： Magnesium alloy Long-period stacking ordered(LPSO)phase Portevin-Le Chatelier effect High temperature

A modified constitutive model for FRP confined concrete in circular sections and its implementation with OpenSees programming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 856-866页

作者： Hui LIU Ming-hua HE yu-qi luan Jia GUO Lu-lu LIU Department of Civil Engineering Tsinghua University Research Institute of Highway of China Ministry of Transport Institute of Chemical Machinery Zhejiang University

OpenSees is a well-recognized open source platform with high compatibility,and it has a well-developed fiber element method to cope with nonlinear structural *** reinforced polymer(FRP)confined concrete can effectively improve the seismic performance of concrete ***,sophisticated constitutive models for FRP confined concrete are not available in the current version of *** this paper,after reviewing several typical FRP confined concrete constitutive models,a modified constitutive model for FRP confined concrete in circular sections was proposed based on Lam and Teng(2003)’s model with four main modifications including the determination of FRP rupture strain,ultimate condition,envelope shape,and hysteretic *** embed the proposed constitutive model into OpenSees is a practical solution for engineering ***,the secondary development of OpenSees New UserMat was briefly demonstrated and a set of critical steps were depicted in a flow ***,with the numerical implementations of a series of FRP confined concrete members covering a wide range of load cases,FRP confinement types and geometric properties,the utility and accuracy of the proposed model compared with Lam and Teng(2003)’s model and new material secondary development in OpenSees were well validated.

关键词： FRP confined concrete Constitutive model OpenSees User material Secondary development

Corilagin alleviates podocyte injury in diabetic nephropathy by regulating autophagy via the SIRT1-AMPK pathway

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World Journal of Diabetes 2024年第9期15卷 1916-1931页

作者： yu Lou yu-Ting luan Wen-Qing Rong yun Gai Department of Preventive Treatment of Disease Seventh People's Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200137China Department of Infectious Diseases Seventh People's Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200137China Department of General Practice(Including Medical Oncology) Seventh People's Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200137China

BACKGROUND Diabetic nephropathy(DN)is the most frequent chronic microvascular consequence of diabetes,and podocyte injury and malfunction are closely related to the development of *** have shown that corilagin(Cor)has hepatoprotective,anti-inflammatory,antibacterial,antioxidant,anti-hypertensive,antidiabetic,and anti-tumor *** To explore the protective effect of Cor against podocyte injury in DN mice and the underlying *** Streptozotocin and a high-fat diet were combined to generate DN mice models,which were then divided into either a Cor group or a DN group(n=8 in each group).Mice in the Cor group were intraperitoneally injected with Cor(30 mg/kg/d)for 12 wk,and mice in the DN group were treated with *** analysis was used to measure the blood lipid *** and eosin staining was used to detect pathological changes in kidney *** and Western blotting were used to assess the protein expression of nephrin and *** podocyte cells(MPC5)were cultured and treated with glucose(5 mmol/L),Cor(50μM),high glucose(HG)(30 mmol/L),and HG(30 mmol/L)plus Cor(50μM).Real-time quantitative PCR and Western blotting RESULTS Compared with the control group,the DN mice models had increased fasting blood glucose,glycosylated hemoglobin,triglycerides,and total cholesterol,decreased nephrin and podocin expression,increased apoptosis rate,elevated inflammatory cytokines,and enhanced oxidative *** of the conditions mentioned above were alleviated after intervention with *** addition,Cor therapy improved SIRT1 and AMPK expression(P<0.001),inhibited reactive oxygen species and oxidative stress,and elevated autophagy in HG-induced podocytes(P<0.01).CONCLUSION Cor alleviates podocyte injury by regulating autophagy via the SIRT1-AMPK pathway,thereby exerting its protective impact on renal function in DN mice.

关键词： Corilagin Podocyte injury Diabetic nephropathy Autophagy High glucose SIRT1-AMPK pathway