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Reformatted method for two-dimensional detector arrays measurement data in proton pencil beam scanning

Nuclear Science and Techniques 2021年第6期32卷 83-93页

作者： Meng-Ya Guo Xiu-Fang li Jie Wang Qi liu Xiu-Zhen Deng Man-Zhou Zhang li-ren shen Yue-Hu Pu Zhi-ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Shanghai APACTRON Particle Equipment Co.Ltd Shanghai 201800China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The spatial resolution of a commercial two-dimensional(2D)ionization chamber(IC)array is limited by the size of the individual detector and the center-to-center distance between *** dose distributions with areas of steep dose gradients,inter-detector dose values are derived by the interpolation of nearby detector readings in the conventional mathematical interpolation of 2D IC array *** may introduce significant errors,particularly in proton spot scanning *** this study,by combining logfile-based reconstructed dose values and detector measurements with the Laplacian pyramid image blending method,a novel method is proposed to obtain a reformatted dose distribution that provides an improved estimation of the delivered dose distribution with high spatial ***,the similarity between the measured original data and the downsampled logfilebased reconstructed dose is regarded as the confidence of the reformatted dose ***,we quantify the performance benefits of this new approach by directly comparing the reformatted dose distributions with 2D IC array detector mathematically interpolated measurements and original low-resolution *** result shows that this new method is better than the mathematical interpolation and achieves gamma pass rates similar to those of the original low-resolution *** reformatted dose distributions generally yield a confidence exceeding 95%.

关键词： 2D ion chamber array detectors Laplacian pyramid image blending High-resolution reformatted methods Pencil beam scanning Proton therapy

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Numerical investigation on ball-sealers transport and diversion performance in shale gas horizontal well based on semi-resolved CFD-DEM

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Particuology 2024年第10期93卷 137-153页

作者： Yinjian Huang Jinzhou Zhao Lan ren Ran lin Jianfa Wu Cheng shen Jianjun Wu Bing li National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China Tianfu Yongxing Laboratory Chengdu610213China Shale Gas Research Institute PetroChina Southwest Oil&Gasfield CompanyChengdu610056China PetroChina Coalbed Methane Company limited Xi’an710082China

In the staged multi-cluster fracturing of shale gas horizontal wells, ball sealers are used to ensure uniform fluid distribution among clusters, a strategy that is both cost-effective and operationally beneficial. Despite these advantages, comprehending the ball sealers' dynamics within the wellbore and their plugging behavior at perforations is still challenging. This complexity results in prediction difficulties regarding their diversion efficiency. To address this, our study utilized a semi-resolved CFD-DEM model based on kernel approximation to simulate the behavior of medium-sized ball sealers in single and multiple cluster scenarios. Our findings from a single cluster scenario reveal that the plugging probability is co-determined by velocity gradients in the fluid ingestion area near the perforation, backflow region, and inertial forces of the ball sealers. As the critical flow rate is achieved, the plugging probability negatively correlated with fluid viscosity and displacement, and positively correlated with the perforation flow ratio (PFR), the difference in particle-fluid density, ball sealer’s diameter, and the ball sealer’s offset from the pipeline center. Temporary plugging control efficiency was used to evaluate the flow balance effect among multiple clusters. The results indicate that an increased number of ball sealers enhances the fault tolerance during the temporary plugging process. Nevertheless, excessive ball sealers might undermine the temporary plugging control efficiency, as perforations with lower fluid inflow rates are unexpectedly plugging. Higher differences in fluid injection rates between clusters led to increased efficiency in temporary plugging control. Premature deployment of ball sealers cannot effectively plug perforations with marginally higher fluid inflow rates, but instead accidently plug intermediate clusters with lower fluid inflow rates. These findings offer a theoretical basis for optimizing the design of ball sealers.

关键词： Gas shale Horizontal wells Ball sealer Semi-resolved CFD-DEM Diversion

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Experimental Investigation on Heat Transfer and Combustion of a Stirling Engine Combustor Fueled by Reformed Gas and Diesel Fuel

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Journal of Thermal Science 2024年第5期33卷 1907-1919页

作者： LAN Jian ZHAO Yanchun liN Guangtao li Yelin ren Zhe LYU Tian shen Mengmeng GU Genxiang HAN Dong Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China Shanghai Marine Diesel Engine Research Institute Shanghai 201108China

Thermochemical recuperation heat recovery is an advanced waste heat utilization technology that can effectively recover exhaust waste heat from oxy-fuel Stirling *** novel combustor of a Stirling engine with thermochemical recuperation heat recovery system is expected to utilize both reformed gas and diesel fuels as sources of *** this research,the effects of various factors,including the H_(2)O addition,fuel distribution ratio(FDR),excess oxygen coefficient,and cyclone structure on the temperature distribution in the combustor,combustion emissions,and external combustion system efficiency of the Stirling engine were experimentally *** the increase of steam-to-carbon ratio(S/C),the temperature difference between the upper and lower heating tubes reduces and the circumferential temperature fluctuation decreases,and the combustion of diesel and reformed gas remains close to complete *** S/C=2,the external combustion efficiency is 80.6%,indicating a 1.6%decrease compared to conventional *** the increase of FDR,the temperature uniformity of the heater tube is improved,and the CO and HC emissions ***,the impact of the FDR on the maximum temperature difference and temperature fluctuation across the heater is *** the FDR rises from 21%to 38%,the external combustion efficiency increases from 87.4%to92.3%.The excess oxygen coefficient plays a secondary role in influencing temperature uniformity and temperature difference,and the reformed gas and diesel fuel can be burned efficiently at a low excess oxygen coefficient of *** an increase in the cyclone angle,the heater tube temperature increases,while the maximum temperature difference at the lower part decreases,and the temperature fluctuation ***,the CO and HC emissions increase,and the external combustion efficiency experiences a decrease.A cyclone angle of 30°is found to be an appropriate value for achieving optimal

关键词： Stirling engine fuel reforming synthetic gas oxy-combustion external combustion efficiency

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High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： Man Zhang Xiao-Xu liu Tian-Yi Ji Yang li Da-Wei sheng Shao-Dong li Pei-Pei ren Ze-Xiang shen School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone(ZIF) and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber(CoP@CF) were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g^(-1) at 0.1 A·g^(-1)after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·g^(-1).The sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Freestanding anodes Sodium-ion batteries

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Preparation and properties of poly(ethylene glycol)-bpoly( 3-acrylamidophenylboronic acid) glucose responsive particles and their hyaluronic acid-based microneedle patches

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 395-410页

作者： Yichuan HONG Haojie YU li WANG Xiang CHEN Di shen Yu WANG Shuning ren Yudi HUANG Jian YANG State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China Zhejiang-Russia Joint Laboratory of Photo-Electro-Magnetic Functional Materials College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China

To overcome the pain and risk of hypoglycemia in insulin administration,glucose-responsive microneedles have been developed by researchers,which could release insulin according to the blood glucose *** designed a kind of particles by a reversible addition-fragmentation chain transfer(RAFT)method containing a phenylboronic acid group as the sensor of glucose and carrier of ***(ethylene glycol)(PEG)-2-(dodecylthio(thiocarbonyl)thio)-2-methylpropionic acid(DDMAT)was synthesized as a macromolecular RAFT agent,which was then reacted with 3-acrylamidophenylboronic acid(AAPBA)to synthesize the block copolymer ***-responsive particles loaded with insulin were prepared by self-assembly based on hydrophilic-hydrophobic *** patches loaded with glucose-responsive particles were prepared using hyaluronic acid as the *** insulin release behavior of the particles in glucose solutions of 0,100,and 400 mg/dL showed significant glucose responsiveness and good *** results of blood glucose control experiments in rats indicate that a single microneedle patch can effectively maintain normal blood glucose for over 7 h.

关键词： Diabetes Hyaluronic acid Phenylboronic acid(PBA) Glucose responsive hydrogel Microneedles

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An Interpretable light Attention-Convolution-Gate Recurrent Unit Architecture for the Highly Accurate Modeling of Actual Chemical Dynamic Processes

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Engineering 2024年第8期39卷 104-116页

作者： Yue li Ning li Jingzheng ren Weifeng shen School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Catalysis and New Environmental Materials School of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

To equip data-driven dynamic chemical process models with strong interpretability,we develop a light attention–convolution–gate recurrent unit(LACG)architecture with three sub-modules—a basic module,a brand-new light attention module,and a residue module—that are specially designed to learn the general dynamic behavior,transient disturbances,and other input factors of chemical processes,*** with a hyperparameter optimization framework,Optuna,the effectiveness of the proposed LACG is tested by distributed control system data-driven modeling experiments on the discharge flowrate of an actual deethanization *** LACG model provides significant advantages in prediction accuracy and model generalization compared with other models,including the feedforward neural network,convolution neural network,long short-term memory(LSTM),and ***,compared with the simulation results of a deethanization model built using Aspen Plus Dynamics V12.1,the LACG parameters are demonstrated to be interpretable,and more details on the variable interactions can be observed from the model parameters in comparison with the traditional interpretable model *** contribution enriches interpretable machine learning knowledge and provides a reliable method with high accuracy for actual chemical process modeling,paving a route to intelligent manufacturing.

关键词： Interpretable machine learning light attention-convolution-gate recurrent unit architecture Process knowledge discovery Data-driven process model Intelligent manufacturing

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The response and anti-stress mechanisms of nitrifying sludge under long-term exposure to Cd Se quantum dots

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Journal of Environmental Sciences 2024年第1期135卷 174-184页

作者： linkai Guo Lei Yang Yongxiang ren shen Cui Xiaotong li Jia Wang Jun Lan Haoqi Lu Yuchao Wang Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key Lab of Northwest Water Resource Environment and EcologyMinistry of EducationXi’an University of Architecture and TechnologyXi’an 710055China

The wide application of CdSe quantum dots(QDs)increases its stress risk to sewage treatment *** study evaluated the response of nitrification performance,floc characteristics and microbial community of nitrifying sludge under long-term exposure to CdSe *** showed CdSe QDs(≥1 mg/L)would decrease the activity of ammonia monooxygenase(AMO).Under the stress of 30 mg/L CdSe QDs,the activity of AMO was reduced by 66%,while the activities of hydroxylamine oxidase and nitrite oxidoreductase were enhanced by 19.1%and 26%,***,the final nitrification effects were not adversely affected,and the production rates of NO_(2)^(-)-N and NO_(3)^(-)-N were ***,CdSe QDs improved biomass concentration in sludge and maintained the stability of sludge *** throughput sequencing analysis showed that CdSe QDs evidently reduced the abundance and diversity of microbial community in nitrifying *** abundances of amino acid metabolism and lipid metabolism were ***,CdSe QDs decreased the fluorescence intensity of tryptophan-like protein from 2,326 to 1,179 *** loosely bound extracellular polymeric substances(EPSs)and from 3,792 to 3,117 *** tightly bound *** relieve CdSe QD stress,the polysaccharide content increased from0.31 to 0.61 mg/g MLSS and intracellular antioxidant defense was *** CdSe QD level increasing to 30 mg/L,the total antioxygenic capacity and the activities of catalase were enhanced up to 411%and 143.2%,***,CdSe QDs had little adverse effects on cell membrane integrity,microbial metabolism and the abundance of Nitrospirae.

关键词： Quantum dots Activated sludge Extracellular polymeric substances Microbial community Antioxidant effect

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Theoretical Analysis of Cooperative Driving at Idealized Unsignalized Intersections

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Tsinghua Science and Technology 2024年第1期29卷 257-270页

作者： shen li Jiawei Zhang Zhenwu Chen li li Department of Civil Engineering Tsinghua UniversityBeijing 100084China Department of Automation Tsinghua UniversityBeijing 100084China shenzhen Urban Transport Planning Center Co. Ltd.Shenzhen 518000China

Cooperative driving is widely viewed as a promising method to better utilize limited road resources and alleviate traffic *** recent years,several cooperative driving approaches for idealized traffic scenarios(i.e.,uniform vehicle arrivals,lengths,and speeds)have been ***,theoretical analyses and comparisons of these approaches are *** this study,we propose a unified group-by-group zipper-style movement model to describe different approaches synthetically and evaluate their *** derive the maximum throughput for cooperative driving plans of idealized unsignalized intersections and discuss how to minimize the delay of *** obtained conclusions shed light on future cooperative driving studies.

关键词： cooperative driving connected and automated vehicles unsignalized intersection

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SHT-based public auditing protocol with error tolerance in FDL-empowered IoVs

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Digital Communications and Networks 2024年第1期10卷 142-149页

作者： Kui Zhu Yongjun ren Jian shen Pandi Vijayakumar Pradip Kumar Sharma School of Computer and Software Nanjing University of Information Science&TechnologyNanjing210044China Peng Cheng Laboratory Shenzhen518000China Department of Computer Science and Engineering University College of Engineering TindivanamTamil Nadu604001India Department of Computing Science University of AberdeenAberdeenAB243UEUK

With the intelligentization of the Internet of Vehicles(lovs),Artificial Intelligence(Al)technology is becoming more and more essential,especially deep *** Deep Learning(FDL)is a novel distributed machine learning technology and is able to address the challenges like data security,privacy risks,and huge communication overheads from big raw data ***,FDL can only guarantee data security and privacy among multiple clients during data *** the data sets stored locally in clients are corrupted,including being tampered with and lost,the training results of the FDL in intelligent IoVs must be negatively *** this paper,we are the first to design a secure data auditing protocol to guarantee the integrity and availability of data sets in FDL-empowered ***,the cuckoo filter and Reed-Solomon codes are utilized to guarantee error tolerance,including efficient corrupted data locating and *** addition,a novel data structure,Skip Hash Table(SHT)is designed to optimize data ***,we illustrate the security of the scheme with the Computational Diffie-Hellman(CDH)assumption on bilinear *** theoretical analyses and performance evaluations demonstrate the security and efficiency of our scheme for data sets in FDL-empowered IoVs.

关键词： Internet of vehicles Federated deep learning Data security Data auditing Data locating and recovery

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Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： li Yuchun shen Chao liu Wei li Dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

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