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Research on the interaction mechanism between quantum dots and radionuclides for the improvement of Cerenkov luminescence imaging

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Science China(Technological Sciences) 2015年第10期58卷 1712-1716页

作者： TANG XiaoBin HOU XiaoXiao SHU DiYun zhai peng Department of Nuclear Science and Engineering Nanjing University of Aeronautics and Astronautics Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Key Laboratory of Biomedical Engineering of Shenzhen College of Medicine Shenzhen University

Cerenkov luminescence imaging(CLI) is a relatively new optical molecular imaging technique. The nature of Stokes shift in quantum dots(QD) can be used to improve the quality of CLI. However, the interaction mechanism of QD with Cerenkov light remains unclear. In this work, the interaction mechanism between QD and radionuclides emitting β rays, γ rays, and Cerenkov light was investigated. The 96-well plates were used to test the different levels of radioactivity of radionuclides with different QD concentrations. Transparent vials were used to determine the relationship between QD fluorescence intensity and the distance from QD to the radionuclide. In addition, black paper was used to block the transmission of Cerenkov light through the QD vials. A linear relationship was found between the number of photons and the radioactivity of radionuclides when the QD concentration was kept constant. Similarly, the number of photons was linearly related to the QD concentration when the radioactivity of radionuclides was kept constant. Furthermore, with the increases in the distance between radionuclides and quantum dots, the number of photons was exponentially decreased. Meanwhile, the number of photons emitted from QD excited by Cerenkov light accounted for 20% the total number of photons excited by 131 I radionuclide. The result proved that QD was not only excited by Cerenkov light but also by other rays.

关键词： Cerenkov luminescence imaging quantum dots radionuclide

Influences of the heterogeneity of viscoelastic medium on postseismic deformation of the 2008 M_(W) 7.9 Wenchuan earthquake

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Geodesy and Geodynamics 2022年第1期13卷 1-10页

作者： Feng Li peng zhai Jinshui Huang Hongbo Tan Mengcheng National Geophysical Observatory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China Earthquake Administration of Jiangsu Province Nanjing210014China CAS Center for Excellence in Comparative Planetology Hefei230026China

The study of postseismic deformation is important for constraining the viscoelastic properties of the Earth and inverting the post-earthquake *** levelling survey revealed that the area near Bei-chuan elevated 5.3 cm about two years after the M_(W) 7.9 Wenchuan earthquake(05/12/2008),during which the area underwent significant downward *** GPS horizontal displacements showed a non-monotonic variation after the Wenchuan *** this study,a 3-D viscoelastic finite element model is employed to simulate the coseismic and postseismic deformation of the Wenchuan *** numerical simulations show that the lateral heterogeneity across the Longmenshan fault plays an important role in the postseismic *** results reveal that the coseismic defor-mation is not sensitive to the horizontal heterogeneity,but the postseismic deformation is sensitive to *** postseismic deformation of the horizontally heterogeneous model is generally consistent with the observations of all geodetic surveys,such as GPS,InSAR and levelling,but not for the horizontally homogenous *** also find that the non-monotonous variation of the postseismic deformation of the Wenchuan earthquake could be explained by a viscoelastic relaxation model with lateral heterogeneous medium across the Longmenshan fault.

关键词： M_(W)7.9 Wenchuan earthquake Postseismic deformation Viscoelastic relaxation Horizontal heterogeneity Three-dimensional finite element

Influences of across-strike heterogeneous viscosity on the earthquake cycle in a three-dimensional strike-slip fault model

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Earthquake Research Advances 2023年第3期3卷 30-41页

作者： peng zhai Feng Li Jinshui Huang Mengcheng National Geophysical Observatory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China Jiangsu Earthquake Agency Nanjing210014China CAS Center for Excellence in Comparative Planetology Hefei230026China

Geodetic observations have shown that there exist large differences in the viscosity of the deep lithosphere across many large strike-slip *** in lithospheric viscosity structure can influence the efficiency of stress transfer and thus may have a significant effect on the earthquake *** now,how the lateral viscosity variation across strike-slip faults affects the earthquake cycles is still not well ***,we investigate the effects of across-strike viscosity variation on long-term earthquake behaviors with a three-dimensional strike-slip fault *** model is a quasi-static model which is controlled by the slip-weakening friction law and powerlaw *** comparing with the reference case,we find that low viscosity on one side of the fault results in a smaller rupture area but with a higher Coulomb stress drop on the ruptured fault *** addition,low viscosity also leads to a small Coulomb stress accumulation *** combined effects increase the earthquake recurrence interval by approximately 10%and the earthquake moments by about 30%when the low viscosity is related to a geothermal gradient of 30 K/*** addition,across-strike viscosity variation causes asymmetric interseismic ground surface deformation *** the viscosity contrast increases,the difference in the interseismic ground surface deformation rate between the two sides of the fault gradually increases,although the asymmetric feature is not *** asymmetry of interseismic ground deformation rate across a strike-slip fault is supposed to result in asymmetric coseismic deformation if the long-term plate motion velocity is *** a result,this kind of asymmetry of interseismic deformation may influence the evaluation of potential earthquake hazards along large strike-slip faults with lateral viscosity contrast.

关键词： Across-strike viscosity variation Friction law Power-law rheology Earthquake cycle Asymmetric interseismic deformation

腹腔镜与胆道镜双镜联合治疗复发性胆总管结石患者疗效研究

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实用肝脏病杂志 2025年第2期28卷 306-309页

作者：翟鹏张华国蒋永军扬州大学附属淮安医院/淮安市第五人民医院普通外科江苏省淮安市223000

目的分析腹腔镜联合胆道镜探查治疗胆道手术后再发胆总管结石患者的疗效。方法2022年1月~2024年6月我院收治的胆道手术后再发的胆总管结石患者108例,被分为A组45例,采用腹腔镜联合胆道镜探查治疗,和B组63例,采用内镜逆行胰胆管造影(ERC... 详细信息

目的分析腹腔镜联合胆道镜探查治疗胆道手术后再发胆总管结石患者的疗效。方法2022年1月~2024年6月我院收治的胆道手术后再发的胆总管结石患者108例,被分为A组45例,采用腹腔镜联合胆道镜探查治疗,和B组63例,采用内镜逆行胰胆管造影(ERCP)/内镜下Oddi's括约肌切开取石术(EST)治疗,随访6个月。采用ELISA法检测血清内毒素(ET)水平,常规检测血清D-乳酸水平。结果A组手术时间、术后住院日和住院费用分别为(102.8±19.1)min、(8.4±1.6)d和(2.6±0.4)万元,均显著多于或长于B组【分别为(81.5±14.6)min、(5.1±1.3)d和(1.9±0.4)万元,P0.05);A组血清ALT、TBIL和ALB水平分别为(45.6±5.8)U/L、(17.2±3.3)μmol/L和(35.7±5.1)g/L,与B组【分别为(43.8±6.0)U/L、(16.4±3.5)μmol/L和(34.6±4.7)g/L】比,无显著性差异(P>0.05);两组术后胆道感染、出血、胆漏和急性胰腺炎等并发症发生率(11.1%对19.1%)比较,无显著性差异(P>0.05);随访6个月,超声检查发现A组无结石复发(0.0%),B组发生结石复发6例(9.5%)。结论采用腹腔镜联合胆道镜探查取石术或ERCP/EST治疗胆道手术后再发性胆总管结石患者的疗效相当,两种方式治疗结石清除率均较高,但后者似乎更容易发生结石复发,值得长期观察。

关键词：胆总管结石腹腔镜胆道镜内镜逆行胰胆管造影内镜下Oddi's括约肌切开取石术治疗

Radiation synthesis and characteristics of PTFE-g-PSSA ion exchange membrane applied in vanadium redox battery

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Nuclear Science and Techniques 2007年第1期18卷 50-54页

作者： peng Jinfen QIU Jinyi NI Jiangfeng zhai Maolin XU peng peng Jing ZHOU Henghui LI Jiuqiang WEI Genshuan Beijing National Laboratory for Molecular Sciences Department of Applied Chemistry College of Chemistry ＆ Molecular Engineering Peking University Beijing 100871 China

Radiation-induced grafting of styrene onto polytetrafluoroethylene (PTFE) membranes was studied by a simultaneous irradiation *** was carded out usingγ-radiation from a ^(60)Co source at room temperature. Effects of absorbed dose,atmosphere,dose rate,and the concentration of initial monomer on the degree of grafting (DOG) were investigated and the most appropriate grafting condition was ***,sulphonation of the grafted PTFE membrane (PTFE-g-PS) was carried out and a series of ion exchange membranes (PTFE-g-PSSA) was *** characterizations of FTIR,TGA,and SEM testified that grafting and sulphonation of the membranes were successfully processed;moreover,grafting of styrene not only occurred in the surface of PTFE membrane,but also in the micropores of the *** exchange capacity (IEC) and conductivity were found increase with the grafting *** results suggest that at a low dose,such as 17 kGy,the ion exchange membrane (IEM) which will be suitable for vanadium redox battery (VRB) use can be obtained.

关键词： PTFE-g-PSSA离子交换膜辐射合成性质钒氧化还原电池

Novel crosslinked alginate/hyaluronic acid hydrogels for nerve tissue engineering

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Frontiers of Materials Science 2013年第3期7卷 269-284页

作者： Min-Dan WANG peng zhai David J. SCHREYER Ruo-Shi ZHENG Xiao-Dan SUN Fu-zhai CUI Xiong-Biao CHEN Division of Biomedical Engineering University of Saskatchewan 57 Campus Dr. Saskatoon SK S7N5A9 Canada Department of Anatomy and Cell Biology University of Saskatchewan 107 Wiggins Rd. Saskatoon SK S7N5E5 Canada School of Materials Science and Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering University of Saskatchewan 57 Campus Dr. Saskatoon SK S7N5A9 Canada

CT： Artificial tissue engineering scaffods can potentially provide supportand guidance for the regrowth of severed axons following nerve injury. In this study a hybrid biomaterial composed of alginate and hyaluronic acid （HA） was synthesized characterized in terms of its suitability for covalent modification, biocompatibility fir living Schwann cells and feasibility to construct three dimensional （3D） Carbodiimide mediated amide formation for the purpose of covalent crosslinking of the HA was carried out in the presence of calcium ions that ionically crosslink *** formation was found to be dependent on the concentrations of cabodiimide and calclum chloride. The double-crosslinked composite hydrogels display blocompatibllity that is comparable to simple HA hydrogels, allowing for Schwann cell survival and significant difference was found between composite hydrogels made from different of alginate and HA. A 3D BioPIotterTM rapid prototyping system was used to fabricats 3D scaffolds. The result indicated that combining HA with alginate facilitated the fabrication process and that 3D scaffolds with porous inner structure can be fabricated ;from the composite hydrogels, but not from HA alone. This information provides a basis for continuing in vitro and in vivo tests of the suitability of alginate/HA hydrogel as a biomaterial to create living cell scaffolds to support nerve regeneration.

关键词： hyaluronic acid (HA) alginate hydrogel scaffold nerve injury tissueengineering

High-performance multifunctional(Hf^(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)Zr_(0.2))C high-entropy ceramic reinforced with low-loading 3D hybrid graphene–carbon nanotube

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Journal of Advanced Ceramics 2023年第2期12卷 341-356页

作者： Jialin SUN Jun ZHAO Yonghui ZHOU peng zhai Xialun YUN Zhifu HUANG Hui ZHANG Guohua ZHANG School of Mechanical Electrical&Information EngineeringShandong University(Weihai)Weihai 264209China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education School of Mechanical EngineeringShandong UniversityJinan 250061China State Key Laboratory for Manufacturing System Engineering School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

There has been growing interest in the high-entropy ceramic(HEC)recently owing to its tailorable compositions and microstructures,versatile properties,together with promising structural and functional ***,inferior fracture toughness(KIC)and damage tolerance restricted many practical applications of the ***,we addressed this challenge by incorporating a threedimensional graphene–carbon nanotube(3D G–CNT)as toughening agent in(Hf_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)Zr_(0.2))*** resulting enhanced 3D G–CNT/(Hf_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)Zr_(0.2))C featured an outstanding toughness of 8.23 MPa·m^(1/2),while remaining superior strength(763 MPa)and hardness(24.7 GPa).An ultralow friction coefficient(0.15)coupled with an ultralow wear rate(w,2.6×10^(−7) mm^(3)/(N·m))in the 3D G–CNT/(Hf_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)Zr_(0.2))C was obtained primarily as a function of lubricating scrolls,in which two-dimensional(2D)graphene acted as a tribolayer,and one-dimensional(1D)carbon nanotubes acted as nano ball bearings embedded ***,the 3D G–CNT/(Hf_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)Zr_(0.2))C exhibited rather low thermal conductivity(κ)yet excellent electrical conductivity(σ,1.3×10^(6) S/m)in comparison with the pure(Hf_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)Zr_(0.2))*** study provided great potential for maximizing the physical and functional properties of the HEC for various applications.

关键词： high-entropy ceramic(HEC) three-dimensional graphene-carbon nanotube(3D G-CNT) toughening lubricating thermal conductivity(κ)/electrical conductivity(σ)

Effect of Power Ultrasonic on Solidification Structure of HT150 Gray Cast Iron

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Journal of Iron and Steel Research International 2005年第6期12卷 33-36页

作者： QI Fei-peng zhai Qi-jie GAO Shou-lei ZHANG Hai-bo DING Li Shanghai University Shanghai 200072 China

Power ultrasonic treatment is an efficient way to improve the solidification structure and mechanical properties of metals. The effect of 600 W power ultrasonic treatment on the solidification process and structure of... 详细信息

关键词： power ultrasonic HT150 gray cast iron graphite morphology solidification

Analysis of vibration reduction characteristics and applicability of steel-spring floating-slab track

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Journal of Modern Transportation 2011年第4期19卷 215-222页

作者： Wanming zhai peng XU Kai WEI Traction Power State Key Laboratory Southwest Jiaotong University Chengdu 610031 China

A coupled dynamics computation model for metro vehicles, along with a steel-spring floating-slab track, is developed based on the theory of vehicle-track coupled dynamics. Using the developed model, the influences of the thickness, length and mass of floating-slab, spring rate and its arrangement space, running speed, etc. on the time and frequency domain characteristics of steel-spring fulcrum force are analyzed. The applicability of steel-spring floatingslab track is discussed through two integrated example cases of metro and buildings possessing distinct natural vibra- tion characteristics. It is concluded that, it is quite significant, in the optimization modular design of the parameters of steel-spring floating-slab track, to take the matching relationship of both the amplitude-frequency characteristics of steel-spring fulcrum force and natural vibration characteristics of integrated structures into comprehensive consideration. In this way the expensive steel-spring floating-slab track can be economically and efficiently utilized according to the site condition, and at the same time, the economic losses and bad social impact resulted from the resonance during usage of steel-spring floating-slab track can be avoided.

关键词： integrated structures natural vibration characteristics subway vibration steel-spring floating-slab track steel-spring fulcrum force frequency spectrum analysis