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人体玻璃体:氧分压的MR成像

国际医学放射学杂志 2013年第3期 269-269页

作者： E.R.Muir Y.Zhang O.San Emeterio Nateras q.peng T.q.Duong 陶志刚 Research Imaging Institute University of Texas Health Science Center

目的开发一种可对人体玻璃体无创性氧分压[p(02)]定量图像的MR成像方法。材料与方法人体研究均通过伦理委员会批准,所有受试者签署知情同意书并符合HIPAA。动物实验研究经动物保护委员会批准。此MR成像方法是用3.0TMR来测量水的纵向弛豫... 详细信息

目的开发一种可对人体玻璃体无创性氧分压[p(02)]定量图像的MR成像方法。材料与方法人体研究均通过伦理委员会批准,所有受试者签署知情同意书并符合HIPAA。动物实验研究经动物保护委员会批准。此MR成像方法是用3.0TMR来测量水的纵向弛豫率(R1)值。R1值通过多个不同p(02)和温度条件下的水模型(n=10)及体外动物玻璃体(n=2)进行校准。人体玻璃体p(02)的成像研究通过3名志愿者(年龄26～28岁)进行,并在不同日期的多个时间段进行,以评估其可重复性。通过采集眼睛睁开和闭合不同状态下的数据评估温度和环境空气的影响。统计分析方法为t检验,P<0.05有统计学意义。结果通过模型及体外动物玻璃体的校准发现R1值在37℃条件下与氧气的关系表现为0.209s-1+p(02)·2.07×10-4s-1/mmHg(1mmHg=0.133kPa),与温度(Δ[1/R1]/ΔT)的关系表现为(0.106±0.009)s/℃。模型与玻璃体的R1值是有差异的。如果不予纠正,玻璃体p(02)会被明显高估(P<0.001)。人体玻璃体p(02)测量图提示有空间差异,整个玻璃体的p(02)为(16.7±6.5)mmHg(闭眼状态下)。眼睛睁开与闭合状态下的测量表明空间相关性的R1值差异可转换为全眼0.34～0.83℃的温度差异。结论本研究建立了一个MR成像方法,可以通过影像无创性地定量分析玻璃体p(02),并且可以评估玻璃体内大分子、温度梯度以及环境空气对玻璃体p(02)值的影响。使用MR成像来测定玻璃体p(02)有可能用于眼科疾病的无创性研究。

关键词： MR 动物玻璃体氧分压

应用增强CT和CA19-9术前预测R0切除后胰腺导管腺癌病人的无病生存率

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国际医学放射学杂志 2024年第2期 251-251页

作者： D.F.Li q.peng L.Y.Wang W.Cai M.Liang S.Y.Liu 朱婉秋

摘要目的探讨术前增强CT和CA19-9联合预测胰腺导管腺癌（PDAC）R0切除术后无病生存期（DFS）的价值。方法回顾性纳入138例接受根治性R0切除术的PDAC病人，

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ATOMIC STATES AND BRITTLENESS OF hcp Ti_3Al-ORDERED-TYPE ALLOYS

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 270-276页

作者： H.J. peng Y.q. Xie College of Chemistry and Chemical Engineering Central South University Changsha 410083 China College of Materials Science and Engineering Central South University Changsha 410083 China

On the basis of the framework of systematic science of alloys （SSA）, the basic information such as states, volumes, and potential energies of characteristic atoms in hcp Ti-Al system have been determined. The average atomic state of the hcp Ti3Al compound consisting of ψ4^Ti and ψ0^Al atoms is 0.75[Ar] （3dn）^0.573 （3dc）^2.1685 （4sc）^0.972 （4sf）^0.3093 ＋ 0.25[Ne] （3sc）^1.32 （3pc）^1.19 （3sf ＋ 3pf）^0.49. The brittleness of the ordered hcp Ti3Al compound has been discussed considering the fundamental factors, which are atomic states, bond networks, potential energy wave planes, and the ratio xTi/xAl. The existence of more pc and more dc directional electrons in the hcp Ti3Al compound lead to considerable brittleness; From bond networks and potential energy wave planes, the hcp Ti3Al compound has poorer ductility than the pure hcp Ti metal and the pure fcc Al metal; The Al-rich hcp Ti3Al ordered type alloys have poorer ductility than the Ti-rich hcp Ti3Al ordered type alloys.

关键词： Ti3Al alloy atomic state brittleness

Toxic effects of crude-oil-contaminated soil in aquatic environment on Carassius auratus and their hepatic antioxidant defense system

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Journal of Environmental Sciences 2009年第5期21卷 612-617页

作者： WANG Yuanyuan ZHOU qixing peng Shengwei MA Lena q NIU Xiaowei Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education of China) College of Environmental Science and Engineering Nankai University Tganjin 300071 China Soil and Water Science Department University of Florida Gainesville FL 32611-0290 USA

Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of C. auratus and the exposed doses could be divided into 3 phases： fishes exposed to the low dose groups （0.5-5.0 g/L） were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the medium dose groups （5.0-25.0 g/L） fishes were dead due to the penetration of toxic substances; at the high dose groups （25.0-50.0 g/L） fishes were dead due to environmental stress. The highest mortality and death speed were found in the 1.0 g/L dose group, and the death speed was sharply increased in the 50.0 g/L dose group in the late phase of exposure. The activities of superoxide dismutase （SOD）, catalase （CAT） and glutathione S-transferase （GST） and the content of malaondialdehyde （MDA） in the hepatic tissues of C. auratus were induced significantly. The activity of SOD was increased and then decreased. It was significantly inhibited in the 50.0 g/L dose group. The activity of CAT was highly induced, and restored to a level which is little more than the control when the exposed doses exceeded 10.0 g/L. The activity of GST was the most sensitive, it was significantly induced in all dose groups, and the highest elevation was up to 6 times in the 0.5 g/L dose group comparing with the control. The MDA content was significantly elevated in the 50.0 g/L dose group, and the changes of the MDA content were opposite with the changes of GST activity.

关键词： crude-oil-contaminated soil ecotoxicology aquatic environment Carassius auratus antioxidant defense system

Crystallization Modulation and Holistic Passivation Enables Efficient Two‑Terminal Perovskite/CuIn(Ga)Se_(2)Tandem Solar Cells

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Nano-Micro Letters 2025年第1期17卷 205-215页

作者： Cong Geng Kuanxiang Zhang Changhua Wang Chung Hsien Wu Jiwen Jiang Fei Long Liyuan Han qifeng Han Yi‑Bing Cheng Yong peng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People’s Republic of China Triumph Photovoltaic Materials Co. Ltd.No.1001 Yannan AvenueHigh‑Tech Development DistrictBengbuAnhui 233000People’s Republic of China College of Materials Science and Engineering Guilin University of TechnologyGuilin 541004People’s Republic of China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–queisser(S–q)***,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device *** this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK *** addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain ***,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing *** a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our *** validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.

关键词： PVK/CIGS TSCs Irregular rough surfaces Modulating the growth PVK/C60 interface recombination

Modified spherical cavity-expansion model for projectile penetration into concrete targets

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Acta Mechanica Sinica 2019年第3期35卷 518-534页

作者： Y.peng H.Wu q.Fang X.Z.Kong College of Liberal Arts and Sciences National University of Defense TechnologyChangsha 410073China Key Laboratory of Performance Evolution and Control for Engineering Structures Tongji UniversityShanghai 200092China Research Institute of Structural Engineering and Disaster Reduction College of Civil EngineeringTongji UniversityShanghai 200092China State Key Laboratory for Disaster Prevention and Mitigation of Explosion and Impact PLA Amy Engineering UniversityNanjing 210007China

A modified spherical cavity-expansion model is developed in this paper.(1) We introduce a piecewise hyperbolic yield criterion suitable for pressure less than fc/3 to describe the mechanical behavior in the elastic region for the elastic-plastic response and modify the crack occurrence condition for the elastic-cracked-plastic response.(2) The hyperbolic yield criterion and a piecewise equation of state (EOS) are adopted for a better description of the plastic behavior of concrete material. Then, the modified model is validated by several projectile penetration tests in both the normal strength concrete (NSC) and ultra-high performance cement-based composite (UHPCC) targets. Finally, the hydrostatic pressure of the targets under rigid ogive-nosed projectile penetrations is found to be nearly within (0, 1.6 GPa), which usually exceeds the range that the shear strength-pressure test data covered. The influence of yield criterion on depth of penetration is discussed and it is recommended that the pressure should arrive at least 400 MPa in the related triaxial compression tests.

关键词： Dynamic cavity-expansion model Projectile Penetration Concrete Depth of penetration

Matching while Learning: Wireless Scheduling for Age of Information Optimization at the Edge

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China Communications 2023年第3期20卷 347-360页

作者： Kun Guo Hao Yang peng Yang Wei Feng Tony q.S.quek School of Communications and Electronics Engineering East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China Zhejiang University/University of Illinois at Urbana-Champaign Institute Zhejiang UniversityHaining 314400China School of Electronic and Information Engineering Beihang UniversityBeijing 100083China Beijing National Research Center for Information Science and Technology Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Information Systems Technology and Design(ISTD)Pillar Singapore University of Technology and DesignSingapore 487372

In this paper,we investigate the minimization of age of information(AoI),a metric that measures the information freshness,at the network edge with unreliable wireless ***,we consider a set of users transmitting status updates,which are collected by the user randomly over time,to an edge server through unreliable orthogonal *** begs a natural question:with random status update arrivals and obscure channel conditions,can we devise an intelligent scheduling policy that matches the users and channels to stabilize the queues of all users while minimizing the average AoI?To give an adequate answer,we define a bipartite graph and formulate a dynamic edge activation problem with stability ***,we propose an online matching while learning algorithm(MatL)and discuss its implementation for wireless ***,simulation results demonstrate that the MatL is reliable to learn the channel states and manage the users’buffers for fresher information at the edge.

关键词： information freshness Lyapunov opti-mization multi-armed bandit wireless scheduling

Reducing force transmissibility in multiple degrees of freedom structures through anti-symmetric nonlinear viscous damping

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Acta Mechanica Sinica 2012年第5期28卷 1436-1448页

作者： Z.-K.peng Z.-q.Lang G.Meng S.A.Billings State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Department of Automatic Control and Systems Engineering University of Sheffield

In the present study, the Volterra series theory is adopted to theoretically investigate the force transmissibility of multiple degrees of freedom （MDOF） structures, in which an isolator with nonlinear anti-symmetric viscous damping is assembled. The results reveal that the anti-symmetric nonlinear viscous damping can significantly reduce the force trans- missibility over all resonance regions for MDOF structures with little effect on the transmissibility over non-resonant and isolation regions. The results indicate that the vibration isolators with an anti-symmetric damping characteristic have great potential to solve the dilemma occurring in the design of linear viscously damped vibration isolators where an increase of the damping level reduces the force transmissibility over resonant frequencies but increases the transmissibility over non-resonant frequency regions. This work is an extension of a previous study in which MDOF structures installed on the mount through an isolator with cubic nonlinear damping are considered. The theoretical analysis results are also verified by simulation studies.

关键词： Nonlinear viscous damping Force transmissibility - Vibration isolation Volterra series

Microstructure and mechanical properties of Mg-to-Al dissimilar welded joints with an Ag interlayer using ultrasonic spot welding

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Journal of Magnesium and Alloys 2020年第2期8卷 552-563页

作者： H.peng D.L.Chen X.F.Bai P.q.Wang D.Y.Li X.q.Jiang College of Engineering and Technology Southwest UniversityTiansheng Road 2Beibei DistrictChongqing 400715China Department of Mechanical and Industrial Engineering Ryerson University350 Victoria StreetTorontoOntario M5B 2K3Canada School of Materials and Energy Southwest UniversityTiansheng Road 2Beibei DistrictChongqing 400715China Department of Chemical and Materials Engineering University of AlbertaEdmontonAlberta T6G 1H9Canada

Lightweight ZEK100-0 Mg alloy and A16022-T43 Al alloy with an Ag interlayer were joined via ultrasonic spot welding(USW),focusing on the microstructural change and tensile lap shear strength of the welded joints in relation to welding ***/Al interface was superseded by Mg/Ag and Al/Ag interfaces,and unfavorable Mg门A-intermetallic compound was *** foil was observed to be intact in the nugget center,while it was broken or dissolved at the nugget edge at high welding energy *** diffusion layer at the Mg/Ag interface consisted of two distinctive sub-layers:Mg3Ag intermetallic compound adjoining Ag foil,and Mg3Ag-l-Mg eutectic structure adjacent to *** a thin diffusion layer consisting mainly of Ag3Al occurred al lhe Al/Ag *** tensile lap shear strength first increased,reached its peak value,and then decreased with increasing welding *** shear strength achieved in the present study was〜31%higher than that of the joint without *** failure occurred at all energy levels,with Ag foil particles or fragments being stuck on both Mg and Al sides due to its intense interaction with Mg and Al via accelerated diffusion during *** results obtained pave the way for the challenging dissimilar welding between Mg and Al alloys.

关键词： Magnesium alloy Aluminum alloy Ultrasonic spot welding Ag interlayer Microstructure Tensile lap shear strength