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Enhanced CT and CT virtual endoscopy in diagnosis of heterotopic pancreas

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World Journal of Gastroenterology 2011年第33期17卷 3850-3855页

作者： dan Wang Xiao-er Wei Lei Yan Yu-Zhen Zhang Wen-Bin Li Institute of Diagnostic and Interventional Radiology The Sixth Affiliated People＇s HospitalShanghai Jiao Tong UniversityShanghai 200233China

AIM:To improve the diagnosis of heterotopic pancreas by the use of contrastenhanced computed tomography(CT)imaging and CT virtual endoscopy(CTVE).METHODS:A total of six patients with heterotopic pancreas,as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University,Shanghai,China,were *** CT and enhanced CT scanning were performed,and the resulting images were reviewed and analyzed using threedimensional postprocessing software,including ***:Four males and two females were *** heterotopic pancreas sites were involved;three occurred in the stomach,including the gastric antrum(n =2)and lesser curvature(n=1),and two were in the duodenal *** one case of heterotopic pancreas lesion occurred in the *** cases had a solid yet soft tissue density that had a homogeneous pattern when viewed by enhanced ***,their CT values were similar to that of the *** ducts of the heterotopic pancreas tissue,one of the characteristic CT features of heterotopic pancreas tissue,were detected in the CT images of two *** images showed normal mucosa around the tissue,which is also an important indicator of a heterotopic ***,none of the CTVE images showed the typical signs of central dimpling or ***:CT,enhanced CT and CTVE techniques provide useful information about the location,growth pattern,vascularity,and condition of the gastrointestinal wall around heterotopic pancreatic tissue.

关键词： Heterotopic pancreas Computed tomography Contrast enhancement Computed tomography virtual endoscopy

Coupling Effect of Heat Transfer and Flow Resistance in the Rifled Tube Water Wall of a Ultra-Supercritical CFB Boiler

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Journal of Thermal Science 2019年第5期28卷 1078-1088页

作者： LI Yaode YANG dong OUYANG Shijie LIU dan WANG Wenyu State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China North China Electric Power Test and Research Institute Co. Ltd Tianjing 300000 China

The coupling factor is used in this study to characterise the combined effect of the heat transfer and resistance characteristics of a rifled tube. Boundary layer theory is utilised to investigate the relationship between the comprehensive coefficient and Reynolds number in two regions, namely, higher and lower than pseudo-critical enthalpy. Results indicate that mass flux exerts a decisive negative influence on the coupling effect, and the impacts of pressure and heat flux are weak. The overall effect decreases rapidly as the mass flux increases, but it increases in the area behind the quasi-critical enthalpy. The coupling effect is also affected by specific heat ratio, thermal acceleration and buoyancy. The correlations of heat transfer and friction resistance are deduced with high precision according to experimental data.

关键词： supercritical pressure heat transfer frictional resistance coupling effect

Numerical Analysis of Emergency River Restoration Scheme for Qingping Mega Debris Flow

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Journal of Mountain Science 2013年第1期10卷 130-136页

作者： CHEN Ri-dong LIU Xing-nian HUANG er GUO Zhi-xue State Key Laboratory of Hydroscience and Engineering Tsinghua University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

The mega debris flow occurred on August 13 th 2010 in Qingping town,China(hereafter called '8.13' Debris Flow) have done great damage to the local habitants as well as to the re-construction projects in the quake-hit areas,and the channel-fill deposit problem caused by the debris flow was the most ***,it is of high possibility that an even severe deposit problem would reappear and result in worse *** order to maximize risk reduction of this problem,relevant departments of the government established a series of emergency river restoration schemes,for which the numerical analysis is an important procedure to evaluate and determine the optimized *** study presents a numerical analysis by applying a twodimensional debris flow model combined with a relevant water-sediment model to simulate the deposit during the progress of the debris flow,and to calculate and analyze the river flow field under both the present condition and different restoration *** results show that the debris flow model,which takes the confluence of the Wenjia Gully to the main river into account,could simulate the deposit process quite *** the reproduced debris flow from the simulation of the '8.13' Debris Flow,the original river flow path has switched to a relatively lower place just along the right bank with a high speed of near 7m.s-1 after being blocked by the deposit,which is highly *** prevent this hazard,a recommended scheme is derived through inter-comparison of different restoration *** shows that the recommended scheme is able to reduce the water level and as well to regulate the flow *** on the given conditions of the mainstream and the tributary confluence for the simulated '8.13' Debris Flow,when encountering a debris flow with deposit volume less than 0.5 million m3,the river channel can endure a 20-year return flood;however,when the deposit volume increases to 2 million m3,the flood capacity of the river will be

关键词： Flash flood Debris flow River restoration Numerical analysis Finite element method

Thermo-induced physically crosslinked polypeptide-based block copolymer hydrogels for biomedical applications

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Regenerative Biomaterials 2023年第1期10卷 933-956页

作者： dan Zhao Yan Rong dong Li Chaoliang He Xuesi Chen CAS Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China College of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Stimuli-responsive synthetic polypeptide-containing block copolymers have received considerable attention in recent ***,unique thermo-induced sol-gel phase transitions were observed for elaborately-designed amphiphilic diblock copolypeptides and a range of poly(ethylene glycol)(PEG)-polypeptide block *** thermo-induced gelation mechanisms involve the evolution of secondary conformation,enhanced intramolecular interactions,as well as reduced hydration and increased chain entanglement of PEG *** physical parameters,including polymer concentrations,sol-gel transition temperatures and storage moduli,were *** polypeptide hydrogels exhibited good biocompatibility in vitro and in vivo,and displayed biodegradation periods ranging from 1 to 5 *** unique thermo-induced sol-gel phase transitions offer the feasibility of minimal-invasive injection of the precursor aqueous solutions into body,followed by in situ hydrogel formation driven by physiological *** advantages make polypeptide hydrogels interesting candidates for diverse biomedical applications,especially as injectable scaffolds for 3D cell culture and tissue regeneration as well as depots for local drug *** review focuses on recent advances in the design and preparation of injectable,thermo-induced physically crosslinked polypeptide *** influence of composition,secondary structure and chirality of polypeptide segments on the physical properties and biodegradation of the hydrogels are ***,the studies on biomedical applications of the hydrogels are intensively ***,the major challenges in the further development of polypeptide hydrogels for practical applications are proposed.

关键词： injectable hydrogels polypeptides stimuli responsive secondary conformation tissue engineering immunotherapy

Preparation and characterization of high-reactivity explosive-based nano-boron microspheres

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Particuology 2024年第10期93卷 125-136页

作者： Chen dong Yi Wang Kanghui Jia dan Song Xiaolan Song Chongwei An School of Materials Science and Engineering North University of ChinaTaiyuan030051China Jinxi Group Shanxi Jiangyang Chemical Co. Ltd.Taiyuan030051China China Ordnance Institute of Science and Technology Beijing100089China School of Environment and Safety Engineering North University of ChinaTaiyuan030051China

Boron nanoparticles,with their remarkably high gravimetric and volumetric calorific values,emerge as the most promising fuel in energetic ***,challenges such as susceptibility to oxidation,high ignition temperature,and low combustion efficiency have constrained their further *** this study,we fabricated high explosives based nano-boron microspheres with uniform size using the electrostatic spray method,in which the boron nanoparticles and high explosives(CL-20 or PETN)are closely bonded together by fluorinated polymer(F2602)and evenly *** results indicated that the microspheres exhibited high sphericity and showed an enhanced antioxidant *** addition of high-energy explosives not only reduced the thermal oxidation temperature of nano-boron powder within the microspheres but also significantly enhanced the pressurization ***,the microspheres with added high-energy explosives released more energy during the combustion *** to physically mixed samples,electrostatically sprayed microspheres with a uniform microstructure still exhibited higher ***,the design and synthesis of microspheres with controllable structures using the electrostatic spray method show promising application prospects.

关键词： Nano-boron CL-20 PETN Electrospraying Ignition and combustion

Ultrafast and Broadband Terahertz Switching Based on Photo-Induced Phase Transition in Vanadium Dioxide Films

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Chinese Physics Letters 2013年第1期30卷 150-153页

作者： CHEN Zhi WEN Qi-Ye dong Kai SUN dan-dan QIU dong-Hong ZHANG Huai-Wu National Key Laboratory of Science and Technology of Communication University of Electronic Science and Technology of ChinaChengdu 610054 State Key Laboratory of Electronic Thin films and Integrated Devices University of Electronic Science&Technology of ChinaChengdu 610054

Single-phase VO_(2) thin films are sputtering deposited on BK7 substrates,and sharp insulator-to-metal phase transition is obtained with a resistivity change of four orders of ***(THz)pump-probe measurements reveal that by illuminating the films with a low pumping power of 143μJ/cm^(2),VO_(2) films exhibit an ultrafast optical switching to THz transmission within 8 ***,the THz switching ratio reaches over 80%in a wide frequency range from 0.3 to 2.5 *** these outstanding features indicate a strong potential of VO_(2) films for broadband terahertz wave switching and modulation applications.

关键词： pumping pump Switching

Late Jurassic-Early Cretaceous tectonic switching in Liaodong Peninsula of the North China Craton and the implications for gold mineralisation

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Science China Earth Sciences 2021年第9期64卷 1537-1556页

作者： dan-Ping YAN Ruoyan KONG Xiaoyu dong Liang QIU Huilong LIU State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing100083China Geophysical Investigation Centre China Geological SurveyLangfang065000China

Constraining the processes of deformation during tectonic switching from compression to extension is difficult because of the scarcity or absence of associated sedimentary and magmatic rocks and weak *** east margin of the eastern North China Craton experienced Early to Middle Jurassic compression and Early Cretaceous ***,the period of tectonic quiescence lasting~13 million years(between 153 and 140 Ma)during which this transition occurred is poorly *** paper reports the identification of small-scale N-S-trending thrust and sinistral strike-slip faults(TSS)and NWtrending thrust and dextral strike-slip faults(TDS)in the Tongyuanpu-Aiyang region,which is part of the northern Liaodong *** of the tectonic stress field using striations,fault planes and kinematics reveals a NW-SE-oriented maximum principal axis(σ1),and sub-horizontalσ2 andσ*** of N-S-trending TSS and NW-trending TDS were arranged with right stepping and resulted in local uplift and erosion at the junctions between fault terminations,which partitioned the Early and Middle Jurassic basins into residual smaller volcanic-sedimentary *** basins were unconformably overlain by small Early Cretaceous volcanic-sedimentary basins,such as those at Tongyuanpu and *** ages and the timing of basin formation constrain the initiation of tectonic switching to 156–153 Ma,and its termination to 140–139 *** suggest that R-R’Riedel shears controlled the formation of the N-S-trending TSS and NW-trending *** R-R’shears were produced by continued sinistral strike-slip and northward growth along the Bohai Bay segment of the Tan-Lu fault zone during the Late Jurassic to early Early Cretaceous,simultaneous with a gradual weakening in the tectonic stress field during a switch in the direction of subduction of the Palaeo-Pacific plate from NW-ward to *** tectonic switching might have promoted the dissolution of gold and migra

关键词： Switch from compression-extension Liaodong Peninsula Late Jurassic-Early Cretaceous R-R’shear Tan-Lu fault zone gold mineralisation

TiO2 sensitized by red-, green-, blue-emissive carbon dots for enhanced H2 production

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Rare Metals 2019年第5期38卷 404-412页

作者： dong-Xue Yang dan Qu Xiang Miao Wen-Shuai Jiang Li An Yuan-Jing Wen dan-dan Wu Zai-Cheng Sun Beijing Key Laboratory for Green Catalysis and Separation Department of Chemistry and Chemical Engineering School of Environmental and Energy Beijing University of Technology

Carbon dots(Cdots)with a broad light absorption range could be a potential stable sensitizer for TiO2,which is an excellent ultraviolet(UV)response ***,we systematically investigated the different color emissive Cdots-sensitized TiO2 for H2 ***,all kinds of Cdots enhanced the photocatalytic properties of *** the Cdots-sensitized TiO2 exhibits visible light H2 production due to their absorption in the visible light *** photocurrent and H2 production amount display strong dependence on the light absorption range of *** blue-emissive Cdots endow the weak H2 production rate due to its weak absorption in the visible *** enhanced photocatalytic activities are mainly contributed to the strong light absorbance and high-efficient charge *** light absorption of green-and red-emissive Cdots is another main factor for the high catalytic activities besides charge separation.

关键词： TiO2 Carbon dots Visible light absorption Sensitizer H2 production

A semi-custom design methodology for design performance optimization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 510-516页

作者： dong-ming LV Pei-yong ZHANG dan-dan ZHENG Xiao-lang YAN Bo ZHANG Li QUAN Institute of VLSI Design Zhejiang University Hangzhou 310027 China

We present a semi-custom design methodology based on transistor tuning to optimize the design performance. Compared with other transistor tuning approaches, our tuning process takes the cross-talk effect into account and prominently reduces the complexity for circuit simulation and analysis by decomposing the circuit network utilizing graph theory. Furthermore, the incremental placement and routing for the corresponding transistor tuning in conventional approaches is not required in our methodology, which might induce timing graph variation and additional iterations for design convergence. This methodology combines the flexible automated circuit tuning and physical design tools to provide more opportunities for design optimization throughout the design cycle.

关键词： Transistor tuning Cross-talk Circuit decomposing