检索结果-南通市图书馆

Chinese Journal of Polymer Science 2023年第3期41卷 459-464,I0010页

作者： zi-ren chen Wu Zhou Lei Shen School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China

Despite extensive researches on the motion of polymer chains on lipid membranes,the effect of membrane fluctuations on polymer chain dynamics remains poorly understood.Here we report single molecule tracking experiments that allow for comparable measurements of polymer chain diffusion dynamics on nanotubular and planar phospholipid membranes.We observe a super-diffusion behavior and no apparent chain-length-dependent mobility of polymer chains on nanotubular membranes,while a Brownian motion and apparent chain-lengthdependent mobility of polymer chains on planar membranes.We suggest the super-diffusion nature of polymer chains may be due to the thermal-fluctuations of lipid nanotubes,which can be described from a statistical thermodynamic phenomenon coupling of polymer chain dynamics and surface thermal fluctuations.We suggest that the existence of surface environment fluctuations should influence the dynamics of the adsorbed polymer chains.This study provides previously uncharacterized insights into polymer diffusion dynamics on thermal-fluctuating flexible surfaces,which is essential to understanding the effect of environment fluctuations on polymer chain behaviors.

关键词： Polymer diffusion Lipid membrane Scaling behavior

Geometric edge effect on the interface of Au/CeO_(2)nanocatalysts for CO oxidation

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 4986-4993页

作者： Hongpeng LiuZhongliang Cao Siyuan Yang Qingye ren Zejian Dong Wei Liu zi-An Li Xing chen Langli Luo Institute of Molecular Plus Tianjin UniversityTianjin 300072China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics(DICP)Chinese Academy of SciencesDalian 116023China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures and School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

The oxide supports play a crucial role in anchoring and promoting the active metal species by geometric confinement and chemical interaction.The design and synthesis of the well-defined oxide support with specific morphology such as size,shape,and exposed facets have attracted extensive research efforts,which directly reflects on their catalytic performance.In this study,using an Au/CeO_(2)-nanorod model catalyst,we demonstrate an edge effect on the Au/CeO_(2)interfacial structure,which shows a prominent effect on the structure-performance relationship in the CO oxidation reaction.This specific“edge-interface”structure features an“edge-on”Au nanoparticles position on rod-shaped CeO_(2)support,confirmed by atomic-scale electron microscopy characterization,which introduces additional degrees of freedom in coordination environment,chemical state,bond length,and strength.Combined with theocratical calculations and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)investigations,we confirmed that this“edge-interface”has distinct adsorption properties due to the change of O vacancy formation energy as well as the chemical states of Au resulting from the electron transfer and redistribution between the metal and the support.These results demonstrate a non-conventional geometric effect of rod-shaped supported metal catalysts on the catalytic performance,which could provide insights into the atomic-precise utilization of catalysts.

关键词： ceria nanorod supported catalyst edge-effect atomic scale

Study on the mechanism and reaction characteristics of metal-supported phosphogypsum as oxygen carrier in a chemical looping gasification application

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第4期138卷 428-438页

作者： Jing Yang Yujie ren Shuoyu chen Jinsuo Lu School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

This study aimed to explore the chemical looping gasification(CLG)reaction characteristics of the metal-supported composite phosphogypsum(PG)oxygen carriers(OCs)and the thermodynamic mechanism.The FactSage 7.1 thermodynamic simulation was used to explore the oxygen release and H_(2)S removal mechanisms.The experimental results showed that the syngas yield of CLG with PG-CuFe_(2)O_(4)was more than that with PG-Fe_(2)O_(3)20/CuO40 or PG-Fe_(2)O_(3)30/CuO30 OC at 1023 K when the water vapor content was 0.3.Furthermore,the maximum syngas yield of the CO selectivity was 70.3% and of the CO_(2)selectivity was 23.8%.The H_(2)/CO value was 0.78,and the highest carbon conversion efficiency was 91.9% in PG-CuFe_(2)O_(4)at the gasification temperature of 1073 K.The metal-supported PG composite oxygen carrier was proved not only as an oxygen carrier to participate in the preparation of syngas but also as a catalyst to catalyze coal gasification reactions.Furthermore,both the experimental results and FactSage 7.1 thermodynamic analysis revealed that the trapping mechanism of H_(2)S by composite OCs was as follows:CuO first lost lattice oxygen as an oxygen carrier to generate Cu_(2)O,which,in turn,reacted with H_(2)S to generate Cu_(2)S.This study provided efficient guidance and reference for OC design in CLG.

关键词： Metal-supported composite phosphogypsum Reaction characteristics Thermodynamic mechanism Chemical looping gasification

Plasma-assisted aerogel interface engineering enables uniform Zn2+ flux and fast desolvation kinetics toward zinc metal batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第8期95卷 29-38页

作者： zijian Xu Zhenhai Shi Zhan Chang Fan Feng Zhuanyi Liu Dongkun Chu Jianguo ren zi-Feng Ma Suli chen Tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of Education School of Chemical and Material Engineering Jiangnan University Shanghai Electrochemical Energy Devices Research Center Department of Chemical Engineering Shanghai Jiao Tong University BTR New Material Group Co. LTD.

The poor reversibility of Zn anodes induced by dendrite growth,surface passivation,and corrosion,severely hinders the practical applicability of Zn metal batteries.To address these issues,a plasmaassisted aerogel（PAG） interface engineering was proposed as efficient ion transport modulator that can simultaneously regulate uniform Zn2+flux and desolvation behavior during battery operation.The PAG with ordered mesopores acted as an ion sieve to homogenize Zn deposition and accelerate Zn2+flux,which is favorable for corrosion resistance and dendrite suppression.Importantly,the plasma-assisted aerogel with abundant hydrophilic groups can facilitate the desolvation kinetics of Zn2+due to the multiple hydrogen-bonding interaction with the activated water molecules,thus accelerating the Zn2+migration kinetics.Consequently,the Zn/Zn cell assembled with PAG-modified separator demonstrates stable plating and stripping behavior(over 1400 h at 1 mA cm-2) and high Coulombic efficiency(99.8% at1 mA cm-2after 1100 cycles),and the Zn‖MnO2full cell shows excellent long-term cycling stability and maintains a high capacity of 154.9 mA h g-1after 1000 cycles at 1 A g-1.This study provides a feasible approach for the large-scale fabrication of aerogel functionalized separators to realize ultra-stable Zn metal batteries.

关键词： Aerogel interface Dendrite growth Plasma Zn metal batteries Zn2+ migration kinetics

Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu chen zi-Shuo Wu Ya-Hui Li Wei chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR techniques.The plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich domain.The time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific features.The quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is deuterated.The ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation measurements.The origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen bonding.Also,the existence of a mobility gradient in the VB unit has been demonstrated.Moreover,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first time.This indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

Engineered extracellular vesicles: A new approach for targeted therapy of tumors and overcoming drug resistance

在线全文

学校读者我要写书评

暂无评论

Cancer Communications 2024年第2期44卷 205-225页

作者： chen Ming-Kun chen zi-Xian Cai Mao-Ping chen Hong chen Zhuang-Fei Zhao Shan-Chao Department of Urology The Third Affiliated Hospital of Southern Medical UniversityGuangzhouGuangdongP.R.China The Third Clinical College Southern Medical UniversityGuangzhouGuangdongP.R.China Luoyang Key Laboratory of Organic Functional Molecules College of Food and DrugLuoyang Normal UniversityLuoyangHenanP.R.China Department of Urology Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdongP.R.China

Targeted delivery of anti-tumor drugs and overcoming drug resistance in malig-nant tumor cells remain significant clinical challenges.However,there are only few effective methods to address these issues.Extracellular vesicles(EVs),actively secreted by cells,play a crucial role in intercellular information transmis-sion and cargo transportation.Recent studies have demonstrated that engineered EVs can serve as drug delivery carriers and showed promising application prospects.Nevertheless,there is an urgent need for further improvements in the isolation and purification of EVs,surface modification techniques,drug assem-bly processes,and precise recognition of tumor cells for targeted drug delivery purposes.In this review,we summarize the applications of engineered EVs in cancer treatment and overcoming drug resistance,and current challenges asso-ciated with engineered EVs are also discussed.This review aims to provide new insights and potential directions for utilizing engineered EVs as targeted delivery systems for anti-tumor drugs and overcoming drug resistance in the near future.

关键词： drug delivery drug resistance extracellular vesicles nanoparticles

Microstructure and mechanical properties of a cast TRIP-assisted multiphase stainless steel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2024年第3期21卷 221-228页

作者： Meng-xin Wang zi-xiang Wu Jing-yu He Xiang chen School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

Stainless steels are used in a wide range of complex environments due to their excellent corrosion resistance.Multiphase stainless steels can offer an excellent combination of strength,toughness and corrosion resistance due to the coexistence of different microstructures.The microstructure and mechanical properties of a novel cast multiphase stainless steel,composed of martensite,ferrite,and austenite,were investigated following appropriate heat treatment processes:solution treatment at 1,050℃ for 0.5 h followed by water quenching to room temperature,and aging treatment at 500℃ for 4 h followed by water quenching to room temperature.Results show reversed austenite is formed by diffusion of Ni element during aging process,and the enrichment of Ni atoms directly determines the mechanical stability of austenite.The austenite with a lower Ni content undergoes a martensitic transformation during plastic deformation.The tensile strength of the specimen exceeds 1,100 MPa and the elongation exceeds 24%after solid solution,and further increases to 1,247 MPa and 25%after aging treatment.This enhancement is due to the TRIP effect of austenite and the precipitation of the nanoscale G-phase pinning dislocations in ferrite and martensite.

关键词： multiphase stainless steel mechanical properties TRIP effect reversed austenite G-phase

Development of underwater electric manipulator based on interventional autonomous underwater vehicle (AUV)

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 238-250页

作者： Xiaohui HU Jiawang chen Hang ZHOU ziqiang ren Ocean cllege Zhejiang UniversityZhoushan 316021China Hainan Institute Zhejiang UniversitySanya 572025China The Engineering Research Center of Oceanic Sensing Technology and Equipment Ministry of EducationZhoushan 316021China

In applications such as marine rescue,marine science,archaeology,and offshore industries,autonomous underwater vehicles(AUVs)are frequently used for survey missions and monitoring tasks,with most operations being performed by manned submersibles or remotely operated vehicles(ROVs)equipped with robotic arms,as they can be operated remotely for days without problems.However,they require expensive marine vessels and specialist pilots to operate them.Scientists exploring oceans are no longer satisfied with the use of manned submersibles and ROVs.There is a growing desire for seabed exploration to be performed using smarter,more flexible,and automated equipment.By improving the field operation and intervention capability of AUVs,large-scale and long-range seafloor exploration and sampling can be performed without the support of a mother ship,making it a more effective,economical,convenient,and rapid means of seafloor exploration and sampling operations,and playing a critical role in marine resource exploration.In this study,we explored the integration technology of underwater electric robotic arms and AUVs and designed a new set of electric manipulators suitable for water depths greater than 500 m.The reliability of the key components was analyzed by finite element analysis and,based on the theory of robot kinematics and dynamics,simulations were performed to verify the reliability of the key components.Experiments were conducted on land and underwater,trajectory tracking experiments were completed,and the experimental data in air and water were compared and analyzed.Finally,the objectives for further research on the autonomous control of the manipulator underwater were proposed.

关键词： Underwater electric manipulator Inverse kinematics Trajectory planning Trajectory tracking accuracy

Identification of marker genes associated with N6-methyladenosine and autophagy in ulcerative colitis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第10期12卷 1750-1765页

作者： Xiao-Yan Liu Dan Qiao Ya-Li Zhang zi-Xuan Liu You-Lan chen ren-Ye Que Hong-Yan Cao Yan-cheng Dai Department of Gastroenterology Shanghai Traditional Chinese Medicine-Integrated HospitalShanghai University of Traditional Chinese MedicineShanghai 200082China Institute of Digestive Diseases Long Hua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200032China Department of Gastroenterology Shu Guang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China

BACKGROUND Both N6-methyladenosine(m6A)methylation and autophagy are considered relevant to the pathogenesis of ulcerative colitis(UC).However,a systematic exploration of the role of the com-bination of m6A methylation and autophagy in UC remains to be performed.AIM To elucidate the autophagy-related genes of m6A with a diagnostic value for UC.METHODS The correlation between m6A-related genes and autophagy-related genes(ARGs)was analyzed.Finally,gene set enrichment analysis(GSEA)was performed on the characteristic genes.Additionally,the expression levels of four characteristic genes were verified in dextran sulfate sodium(DSS)-induced colitis in mice.RESULTS GSEA indicated that BAG3,P4HB and TP53INP2 were involved in the inflammatory response and TNF-αsignalling via nuclear factor kappa-B.Furthermore,polymerase chain reaction results showed significantly higher mRNA levels of BAG3 and P4HB and lower mRNA levels of FMR1 and TP53INP2 in the DSS group compared to the control group.CONCLUSION This study identified four m6A-ARGs that predict the occurrence of UC,thus providing a scientific reference for further studies on the pathogenesis of UC.

关键词： Ulcerative colitis m6A Autophagy Characteristic genes Immune infiltration

Surgical treatment of an old avulsion fracture of the ischial tuberosity and ischial ramus: A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Orthopedics 2024年第1期15卷 94-100页

作者： zi-Ru chen Shi-Jie Liao Fu-Chun Yang Department of Orthopedic Trauma and Hand Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities.According to previous literature,the most commonly involved sports are soccer,sprinting,and gymnastics,in descending order.Dance-induced avulsion fracture of the ischial tuberosity and ischial ramus is extremely clinically rare.CASE SUMMARY A case of a neglected avulsion fracture of the ischial tuberosity and ischial ramus was diagnosed in a young female dancer who complained of pain and restricted movement of her right hip.She stated that she had suffered the injury while performing a split leap during a dance performance 9 mo prior.Eventually,she underwent surgery and obtained satisfactory treatment results.CONCLUSION Early diagnosis of these fractures is important to ensuring early proper treatment towards a quicker recovery.For old fractures with nonunion and chronic buttock pain,surgery is a preferred therapeutic choice with good treatment outcomes.

关键词： Ischial tuberosity Ischial ramus Avulsion fracture Delayed diagnosis Splitleap injury Case report