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Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： xin Fu Zhen Lu Shen Li Zheng-Hong Luo Lin-xi hou department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(deS)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with deS to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of deS for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps

Early Triassic Volcanic Rocks in the Western Yarlung Zangbo Suture Zone:Implications for the Opening of the Neo-Tethys Ocean

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 324-336页

作者： HE Juan LI Yalin hou Yunling Zhou Aorigele WEI Yushuai CHEN xi DAI Jingen School of Civil Engineering and Architecture West Yunnan University of Applied SciencesDaliYunnan 671006China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100080China West Yunnan University of Applied Sciences DaliYunnan 671006China MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100080China

In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern xizang(Tibet)yielded an age of 247±3 *** to whole rock geochemical and Sr-NdPb isotopic data,the Early Triassic samples could be divided into two groups:Group 1 with P-MORB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70253–0.70602,ε_(Nd)(t)values of 4.2–5.3,(^(206)Pb/^(204)Pb)_(t)ratios of 16.353–18.222,(^(207)Pb/^(204)Pb)_(t)ratios of 15.454–15.564,and(^(208)Pb/^(204)Pb)_(t)ratios of 35.665–38.136;Group 2 with OIB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70249–0.70513,ε_(Nd)(t)values of 4.4–4.9,(^(206)Pb/^(204)Pb)_(t)ratios of 17.140–18.328,(^(207)Pb/^(204)Pb)_(t)ratios of 15.491–15.575,and(^(208)Pb/^(204)Pb)_(t)ratios of 36.051–*** 2 rocks formed by partial melting of the mantle source enriched by a former plume,and assimilated continental crustal material during melt *** formation of Group 1 rocks corresponds to the mixing of OIB melts,with the same components as Group 2 and *** Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo-Tethys in southern xizang(Tibet).

关键词： rift Early Triassic magmatism Yarlung Zangbo Suture Zone Neo-Tethys Southern xizang Tibet

A Fine-grained Building Height Control Method for Heritage Areas from the Perspective of Visual Integrity

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Journal of Geodesy and Geoinformation Science 2024年第2期7卷 66-79页

作者： WANG xi hou Miaole CHEN Fan National Marine Data and Information Service Tianjin 300171China The International Joint Laboratory of Safety and Energy Conservation for Ancient Buildings Beijing University of Civil Engineering and ArchitectureBeijing 102616China

This study proposes a refined methodology for controlling building heights in heritage *** order to protect the visual integrity of the heritage area,buildings should not obstruct the view from important site points and viewpoints to the *** calculating the building height thresholds that buildings should not obscure the view from each viewpoint,the results of which are weighted and superimposed,and the values are extracted to each building unit as a refined building height control *** study takes the Zhoukoudian area as a case study,applies the refined building height control criterion to the Zhoukoudian Site,and relies on this refined criterion to assess the visual integrity of the Zhoukoudian area,so as to realize the scientific planning and monitoring of the Zhoukoudian *** refined building height control method can be applied to building height planning and visual landscape protection in large heritage areas.

关键词： building height control visual integrity assessment observation points

Silica-modified Pt/TiO_(2) catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

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Chinese Journal of Chemical Engineering 2024年第6期70卷 189-198页

作者： Zhengjian hou Yuanyuan Zhu Hua Chi Li Zhao Huijie Wei Yanyan xi Lishuang Ma xiang Feng Xufeng Lin College of Chemistry and Chemical Engineering China University of Petroleum(East China)Qingdao 266580China Advanced Chemical Engineering and Energy Materials Research Center China University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China

Tuning Strong Metal-support Interactions(SMSI)is a key strategy to obtain highly active catalysts,but conventional methods usually enable TiO_(x) encapsulation of noble metal components to minimize the exposure of noble *** study demonstrates a catalyst preparation method to modulate a weak encapsulation of Pt metal nanoparticles(NPs)with the supported TiO_(2),achieving the moderate suppression of SMSI *** introduction of silica inhibits this encapsulation,as reflected in the characterization results such as XPS and HRTEM,while the Ti^(4+) to Ti^(3+) conversion due to SMSI can still be found on the support ***,the hydrogenation of cinnamaldehyde(CAL)as a probe reaction revealed that once this encapsulation behavior was suppressed,the adsorption capacity of the catalyst for small molecules like H_(2) and CO was enhanced,which thereby improved the catalytic activity and facilitated the hydrogenation of ***,the introduction of SiO_(2) also changed the surface structure of the catalyst,which inhibited the occurrence of the acetal reaction and improved the conversion efficiency of C=O and C=C *** manipulation of SMSI formation and its consequence on the performance in catalytic hydrogenation reactions are discussed.

关键词： Pt catalyst Silica modification Hydrogenation Cinnamaldehyde Strong metal-support interaction

Effect of acacetin on inhibition of apoptosis in Helicobacter pyloriinfected gastric epithelial cell line

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3624-3634页

作者： Qi-xi Yao Zi-Yu Li hou-Le Kang xin He Min Kang department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina department of Orthopaedics The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina department of Emergency Luzhou People’s HospitalLuzhou 646000Sichuan ProvinceChina

BACKGROUND Helicobacter pylori(***)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atypical gastric hyperplasia to gastric *** eradication of *** is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric ***,which has multifaceted pharmacological activities such as anti-cancer,anti-inflammatory,and antioxidative properties,has been extensively investigated across various ***,the impact and underlying mechanisms of action of acacetin on ***-infected gastric mucosal epithelial cells remain *** To explore the defensive effects of acacetin on apoptosis in ***-infected GES-1 cells and to investigate the underlying *** GES-1 cells were treated with *** and acacetin in *** viability was assessed using the CCK-8 assay,cell mortality rate via lactate dehydrogenase assay,alterations in cell migration and healing capacities through the wound healing assay,rates of apoptosis via flow cytometry and TUNEL staining,and expression levels of apoptosis-associated proteins through western blot *** *** infection led to decreased GES-1 cell viability,increased cell mortality,suppressed cell migration,increased rate of apoptosis,increased expressions of Bax and cle-caspase3,and decreased Bcl-2 ***,acacetin treatment enhanced cell viability,mitigated apoptosis induced by *** infection,and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved *** Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in ***-infected GES-1 cells,thereby exerting a protective effect on gastric mucosal epithelial cells.

关键词： Gastric epithelial GES-1 cells Helicobacter pylori Infection Acacetin Antibiotic resistance Apoptosis

Boosting ultra-wide temperature dielectric stability of multilayer ceramic capacitor through tailoring the combination types of polar nanoregions

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Journal of Materiomics 2024年第4期10卷 751-761页

作者： Jiacheng Liu Kaibiao xi Beibei Song Huarong Cheng xiaole Yu Mupeng Zheng Mankang Zhu Yudong hou College of Materias Science and Engineering Key Laborutory of Advanced Functional Materials Education Ministry of China Beijing University of TechnologyBeijing100124China Materials R&D department Beijing Yuanliu Hongyuan Eletronic Technology CompanyLtdBeijing102600China

With the rapid development of space exploration and new energy vehicles,it is urgent to build ultra-wide temperature multilayer ceramic capacitors(UWT MLCCs)to match electronic circuits that can withstand harsh environmental *** ferroelectrics with diffuse phase transition feature are potential dielectrics for the construction of UWT ***,how to ensure high dielectric constant together with low dielectric loss in the wide temperature region is still a big ***,the above difficulties are addressed by tailoring the combination types of polar nanoregions(PNRs)in the(1-x)(0.8Na_(0.5)Bi_(0.5)TiO_(3)-0.2K_(0.5)Bi_(0.5)TiO_(3))-xNaTaO3(NBT-KBT-xNT)*** with PNRS types of P4bm+R3c and P4bm+Pbnm,the combination type of P4bm+Pbnm+R3c PNRs in NBT-KBT-0.31NT is the most beneficial to obtain comprehensive excellent dielectric performance because it can balance the relationship between high dielectric constant and temperature stability over a wide temperature ***,by optimizing the laminating pressure and co-firing temperature to realize a tight interfacial structure between the dielectric layer and the Pt inner electrode,a record-high dielectric constant(er=(907%±15%))together with low dielectric loss(tan δ≤0.025)is achieved over an ultra-wide range from-61℃ to 306℃ for NBT-KBT-0.31 NT MLCC,demonstrating that tailoring the combination types of PNRs is a powerful strategy in designing UWT MLCC dielectrics.

关键词： Lead-free dielectrics Ultra-wide temperature Multilayer ceramic capacitor Polar nanoregion

Irisin-loaded electrospun core-shell nanofibers as calvarial periosteum accelerate vascularized bone regeneration by activating the mitochondrial SIRT3 pathway

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Regenerative Biomaterials 2024年第1期3卷 44-57页

作者： xi Hua Mingzhuang hou Lei deng Nanning Lv Yong Xu Xuesong Zhu Huilin Yang Qin Shi Hao Liu Fan He department of Orthopaedics The First Affiliated Hospital of Soochow UniversitySoochow UniversitySuzhou 215006China Orthopaedic Institute Suzhou Medical CollegeSoochow UniversitySuzhou 215000China department of Orthopedics Suzhou Wuzhong People’s HospitalSuzhouJiangsu Province 215128China department of Orthopedic Surgery Lianyungang Clinical College of Xuzhou Medical UniversityLianyungang 222003China

The scarcity of native periosteum poses a significant clinical barrier in the repair of critical-sized bone *** challenge of enhancing regenerative potential in bone healing is further compounded by oxidative stress at the fracture ***,the introduction of artificial periosteum has demonstrated its ability to promote bone regeneration through the provision of appropriate mechanical support and controlled release of proosteogenic *** this study,a poly(L-lactic acid)(PLLA)/hyaluronic acid(HA)-based nanofibrous membrane was fabricated using the coaxial electrospinning *** incorporation of irisin into the core-shell structure of PLLA/HA nanofibers(PLLA/HA@Irisin)achieved its sustained *** vitro experiments demonstrated that the PLLA/HA@Irisin membranes exhibited favorable *** osteogenic differentiation of bone marrow mesenchymal stem cells(BMMSCs)was improved by PLLA/HA@Irisin,as evidenced by a significant increase in alkaline phosphatase activity and matrix ***,PLLA/HA@Irisin significantly enhanced the mitochondrial function of BMMSCs via the activation of the sirtuin 3 antioxidant *** assess the therapeutic effectiveness,PLLA/HA@Irisin membranes were implanted in situ into critical-sized calvarial defects in *** results at 4 and 8 weeks post-surgery indicated that the implantation of PLLA/HA@Irisin exhibited superior efficacy in promoting vascularized bone formation,as demonstrated by the enhancement of bone matrix synthesis and the development of new blood *** results of our study indicate that the electrospun PLLA/HA@Irisin nanofibers possess characteristics of a biomimetic periosteum,showing potential for effectively treating critical-sized bone defects by improving the mitochondrial function and maintaining redox homeostasis of BMMSCs.

关键词： periosteum irisin mitochondrial function critical-sized bone defect redox homeostasis

Torque effect on vibration behavior of high-speed train gearbox under internal and external excitations

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Railway Engineering Science 2024年第2期32卷 229-243页

作者： Yue Zhou xi Wang Hongbo Que Rubing Guo xinhai Lin Siqin Jin Chengpan Wu Yu hou School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China CRRC Qishuyan Institute Co. Ltd.No.258Wuyi RoadQishuyanChangzhou 213011China Frontiers Science Center for Smart High-Speed Railway System Beijing Jiaotong UniversityBeijing 100044China

The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavior in the actual service *** paper focuses on the gearbox in the high-speed train to carry out the bench test,in which various operat-ing conditions(torques and rotation speeds)were set up and the excitation condition covering both internal and external was *** responses on multiple positions of the gearbox were acquired in the test and the vibration behavior of the gearbox was ***,a stochastic excitation modal test was also carried out on the test bench under different torques,and the modal parameter of the gearbox was ***,the sweep frequency response of the gearbox under gear meshing excitation was analyzed through dynamic *** results showed that the torque has an attenuating effect on the amplitude of gear meshing frequency on the gearbox,and the effect of external excitation on the gearbox vibration cannot be ignored,especially under the rated operating *** was also found that the torque affects the modal param-eter of the gearbox *** torque has a great effect on both the gear meshing stiffness and the bearing stiffness in the transmission system,which is the inherent reason for the changed modal characteristics observed in the modal test and affects the vibration behavior of the gearbox consequently.

关键词： High-speed train Gearbox Bench test Vibration behavior Modal identification

Cystic hepatic echinococcosis with intrabiliary rupture

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Hepatobiliary Surgery and Nutrition 2024年第3期13卷 573-574页

作者： Jianming Ma Qifu Yan Zha xi Yun Dan Yucheng hou Rui Tang General Surgery department Lhasa People’s HospitalLhasaChina Hepatopancreatobiliary Center Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijingChina

A 43-year-old Tibetan female was brought to the department of general surgery with abdominal *** tomography(CT)scan revealed cystic hepatic echinococcosis in the right liver(Figure 1A).Further magnetic resonance cholangiopancreatography showed that there were cyst-biliary communications at right posterior bile duct,and several hydatid cysts inside common bile duct(Figure 1B,yellow arrow head showed rupture,white arrow heads showed bile duct hydatid cysts).Low confluence of right posterior bile duct to the common hepatic duct suggests biliary *** serum total bilirubin was normal,serum alkaline phosphatase and gamma-glutamyl transpeptidase were elevated mildly with the value of 278 and 107 U/L *** underwent right hemihepatectomy plus choledochoscopic hydatid cysts extraction through right posterior hepatic duct stump(Figure 1C,yellow arrow head showed right posterior bile duct stump,white arrow heads showed bile duct hydatid cysts).To prevent the spread of echinococcosis,we covered the surgical area with hypertonic saline gauze.A large number of hydatid cysts presented inside hepatectomy specimen that mixed with a lot of bile(Figure 1D).Hydatid cyst inside bile duct was removed completely,and postoperative recovery was *** removed all the liver cysts,and no signs of any lesion residue in post-operative image.

关键词： rupture hepatic biliary