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A new sampler for simulating aerosol deposition in the respiratory tract

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Nuclear Science and Techniques 2008年第3期19卷 169-173页

作者： LI Dehong ZHUO Weihai yi Yanling CHEN bo liu Haikuan Institute of Radiation Medicine Fudan University Shanghai 200032 China

For estimation of the deposition fractions of radon progeny in different regions of the respiratory tract, a new sampler consisting of three different configurations of sampling heads was developed. The deposition fractions of aerosols on the wire screens inside the sampling heads were calculated with the fan model of filtration theory. The deposition fractions of aerosols in different regions of the respiratory tract were calculated with the lung dose evaluation program (LUDEP)developed by National Radiological Protection board (NRPB) as references. In general indoor and mine environments, the deviation between the deposition fractions of attached aerosol on the wire screens designed in this study and its reference values in the respiratory tract is less than 5%. It is possible to accurately estimate the deposition fractions of radon progeny in different regions of the respiratory tract through mimic measurements of radon progeny collected with the new sampler.

关键词：放射性污染环境放射学气溶胶呼吸过程

Mathematical modeling of flow field in slab continuous casting mold considering mold powder and solidified shell with high temperature quantitative measurement

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Journal of Iron and Steel Research International 2022年第3期29卷 445-461页

作者： yi-bo liu Jian Yang Chao Ma Tao Zhang Fu-bin Gao Tai-quan Li Jun-li Chen State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai200444China Technology Center HBIS Handan Iron and Steel Group Co.Ltd.Handan56015HebeiChina

Optimization of mathematical model of flow field in slab continuous casting mold was performed by means of industrial measurement and mathematical *** rod deflection method was used to quantitatively measure the velocities near the mold surface at high *** measurement results were compared with the simulation results of three mathematical models at different argon gas flow rates of 6,10 and 14 L min^(−1).The model 1 neglects the mold powder layer,thermal effect and solidified *** model 2 only considers the influence of mold powder *** model 3 considers the influence of mold powder layer,thermal effect and solidified shell on the flow *** all three models,the diameter of argon bubbles obeys Rosin-Rammler distribution fitted according to the experimental data of others’previous *** increasing the argon gas flow rate,the velocity of liquid steel near the mold surface *** model 1 seriously underestimates the shear stress of liquid steel near the mold surface,and its calculation results show higher velocity near the mold surface,lower turbulent kinetic energy and wider distribution of argon gas bubbles in the *** simulation results of model 2 only considering the viscous resistance of the mold powder layer to liquid steel makes the velocity near the surface lower than the measurement results *** calculated velocities near the mold surface with model 3 are in best agreement with the measured results,showing the reasonable spatial distribution range of argon bubbles in the mold and the moderate turbulent kinetic *** the present conditions,the best argon gas flow rate is 10 L min^(−1) due to the moderate velocity near the mold surface,the appropriate distribution of argon gas bubbles in the mold and the smallest fluctuation amplitude on the mold surface.

关键词： Flow field Mold powder layer Solidified shell Rosin-Rammler distribution Mathematical modeling Rod deflection method

Exploring hidden-charm and hidden-strange hexaquark states from lattice QCD

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 30-37页

作者： Hang liu Jinchen He liuming liu Peng Sun Wei Wang yi-bo Yang Qi-An Zhang INPAC Key Laboratory for Particle Astrophysics and Cosmology(MOE)Shanghai Key Laboratory for Particle Physics and CosmologySchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Maryland Center for Fundamental Physics Department of PhysicsUniversity of MarylandCollege ParkMaryland 20742USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing 100049/Hangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Physics Beihang UniversityBeijing 102206China

Based on five different ensembles of newly generated(2+1)-flavor configurations with pion mass of approximately mπ■(140-310)MeV,we present a lattice analysis of hidden-charm and hidden-strange hexaquarks with the quark content■.The correlation matrices of two types of operators with JPC=0++,0-+,1++and 1--are simulated to extract the masses of the hexaquark candidates,which are subsequently extrapolated to the physical pion mass and continuum *** results indicate that ground state masses are below the■threshold and provide a characteristic signal for the experimental discovery of hexaquark candidates,which may enrich the versatile structure of multiquarks;moreover,it is an indispensable step to decipher the nonperturbative nature of the fundamental interactions of quarks and gluons.

关键词： quantum chromodynamics lattice QCD multiquark states

Risk Assessment of Deep-Water Horizontal X-Tree Installation

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China Ocean Engineering 2024年第2期38卷 210-220页

作者： MENG Wen-bo FU Guang-ming HUANG yi liu Shu-jie HUANG Liang GAOYong-hai CNOOC China Limited Zhanjiang BranchZhanjiang 524057China Key Laboratory of Unconventional Oil and Gas Development Ministry of Education(China University of Petroleum(East China))Qingdao 266580China

Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a modular risk evaluation model based on a fuzzy fault ***,through the analysis of the main process oftree down and combining the Offshore&Onshore Reliability Data(OREDA)failure statistics and the operation procedure and the data provided by the job,the fault tree model of risk analysis of the tree down installation was ***,by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles,quantitative analysis was carried out,and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top ***,through a sensitivity analysis of basic events,the basic events of top events significantly affected were determined,and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation.

关键词： subsea horizontal X-tree risk assessment fuzzy fault tree modular risk evaluation model

CO_(2) capture by modified clinoptilolite and its regeneration performance

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International Journal of Coal Science & Technology 2024年第2期11卷 81-90页

作者： bo Jiang bo Zhang Xuqin Duan yi Xing School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants University of Science and Technology BeijingBeijing 100083China YangQuan Coal Industry(Group)Co.Ltd. Yangquan 045000China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

This study focuses on CO_(2) capture by pressure swing adsorption(PSA),with modified clinoptilolite as the *** clinoptilolite is modified by roasting,by acid pickling,by a combination of acid pickling and roasting,and by ion *** by acid pickling-roasting and by ion exchange are found to give the highest CO_(2) adsorption capacities,of 730 mL/g and 876.7 mL/g,*** is found that regeneration of clinoptilolite by a combination of vacuum desorption and heating enables recovery of as much as 89%of its previous CO_(2) adsorption *** examine the CO_(2) adsorption capacity of clinoptilolite when applied to mixed gas,a simulated coking exhaust containing 12%CO_(2) and 4%O_(2) is used,and it is found that ion exchange modified clinoptilolite achieves a CO_(2) removal efficiency of 92.5%.A BET test reveals that acid pickling-roasting and Na^(+) modification enhance the porosity of clinoptilolite,thereby improving its adsorption *** work demonstrates the feasibility of applying modified clinoptilolite as an effective adsorbent for COO_(2)capture,providing a promising tool for dealing with greenhouse gases.

关键词： Clinoptilolite Carbon dioxide capture Pressure swing adsorption(PSA)

Enhancing thermoelectric performance in P-type Mg_(3)Sb_(2)-based Zintls through optimization of band gap structure and nanostructuring

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Journal of Materials Science & Technology 2024年第3期170卷 25-32页

作者： yi-bo Zhang Ji-Sheng Liang Chengyan liu Qi Zhou Zhe Xu Hong-bo Chen Fu-cong Li ying Peng Lei Miao Guangxi Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesMinistry of EducationSchool of Material Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory for Relativity Astrophysics Center on Nanoenergy ResearchGuangxi Key Laboratory of Processing for Nonferrous Metal and Featured MaterialsSchool of Physical Science&TechnologyGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Precision Navigation Technology and Application Guilin University of Electronic TechnologySchool of Information and CommunicationGuilin 541004China

P-type Mg_(3)Sb_(2)-based Zintls have attracted considerable interest in the thermoelectric(TE)field due to their environmental friendliness and low ***,compared to their n-type counterparts,they show relatively low TE performance,limiting their application in TE *** this work,we simultaneously introduce Bi alloying at Sb sites and Ag doping at Mg sites into the Mg_(3)Sb_(2)to coopera-tively optimize the electrical and thermal properties for the first time,acquiring the highest ZT value of∼0.85 at 723 K and a high average ZT of 0.39 in the temperature range of 323-723 K in sample Mg_(2.94)Ag_(0.06)Sb_(1.9)Bi_(0.1).The first-principle calculations show that the codoping of Ag and Bi can shift the Fermi level into the valence band and narrow the band gap,resulting in the increased carrier concentration from 3.50×10^(17)cm^(-3)in the reference Mg 3 Sb 0.9 Bi 0.1 to∼7.88×10^(19)cm^(-3)in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** a result,a remarkable power factor of∼778.9μW m^(-1)K^(-2)at 723 K is achieved in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi ***,a low lattice thermal conductivity of∼0.48 W m^(-1)K^(-1)at 723 K is also obtained with the help of phonon scattering at the distorted lattice,point defects,and nano-precipitates in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** synergistic effect of using the multi-element co-doping/-alloying to optimize electrical properties in Mg_(3)Sb_(2)holds promise for further improving the TE performance of Zintl phase materials or even others.

关键词： Thermoelectric materials Band engineering Nanostructuring P-type Mg_(3)Sb_(2) Ag and Bi Co-doping

Prognostic value of a nomogram model for postoperative liver metastasis of colon cancer

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1055-1065页

作者： De-Xin Cheng Kang-Di Xu Han-bo liu yi liu Department of Interventional Medicine Zhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina General Surgery Cancer CenterDepartment of Vascular SurgeryZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina

BACKGROUND Colon cancer is one of the most common malignant tumors of the digestive *** metastasis after colon cancer surgery is the primary cause of death in patients with colon *** To construct a novel nomogram model including various factors to predict liver metastasis after colon cancer *** We retrospectively analyzed 242 patients with colon cancer who were admitted and underwent radical resection for colon cancer in Zhejiang Provincial People’s Hospital from December 2019 to December *** were divided into liver metastasis and non-liver metastasis ***,age,and other general and clinicopathological data(preoperative blood routine and biochemical test indexes)were *** risk factors for liver metastasis were analyzed using singlefactor and multifactorial logistic regression.A predictive model was then constructed and evaluated for *** Systemic inflammatory index(SII),C-reactive protein/albumin ratio(CAR),red blood cell distribution width(RDW),alanine aminotransferase,preoperative carcinoembryonic antigen level,and lymphatic metastasis were different between groups(P<0.05).SII,CAR,and RDW were risk factors for liver metastasis after colon cancer surgery(P<0.05).The area under the curve was 0.93 for the column-line diagram prediction model constructed based on these risk factors to distinguish whether liver metastasis occurred *** actual curve of the column-line diagram predicting the risk of postoperative liver metastasis was close to the ideal curve,with good *** prediction model curves in the decision curve analysis showed higher net benefits for a larger threshold range than those in extreme cases,indicating that the model is *** Liver metastases after colorectal cancer surgery could be well predicted by a nomogram based on the SII,CAR,and RDW.

关键词： Systemic immunoinflammatory index C-reactive protein/albumin ratio Erythrocyte distribution width Colon cancer Liver metastasis Novel nomogram model

Self-Driven Photo-Polarized Water Molecule-Triggered Graphene-Based Photodetector

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Research 2024年第2期2023卷 273-283页

作者： Shisheng Lin Chang liu Xin Chen yi Zhang Hongtao Lin Xutao Yu Yujiao bo Yanghua Lu College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027P.R.China Hangzhou Gelanfeng Technology Co.Ltd Hangzhou 310051P.R.China State Key Laboratory of Modern Optical Instrumentation Zhejang UniversityHangzhou 310027P.R.China Key Laboratory of Wide Bandgap Semiconductor Materials and Devices HCSemitek CorporationYiwu 322009P.R.China Smart Materials for Architecture Research Lab Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100P.R.China

Flowing water can be used as an energy source for generators,providing a major part of the energy for daily ***,water is rarely used for information or electronic ***,we present the feasibility of a polarized liquid-triggered photodetector in which polarized water is sandwiched between graphene and a *** to the polarization and depolarization processes of water molecules driven by photogenerated carriers,a photo-sensitive current can be repeatedly produced,resulting in a high-performance *** response wavelength of the photodetector can be fine-tuned as a result of the free choice of semiconductors as there is no requirement of lattice match between graphene and the *** zero voltage bias,the responsivity and specific detectivity of Gr/NaCl(0.5 M)W/N-GaN reach values of 130.7 mA/W and 2.3×10^(9)Jones under 350 nm illumination,***,using a polar liquid photodetector can successfully read the photoplethysmography signals to produce accurate oxygen blood saturation and heart *** with the commercial pulse oximetry sensor,the average errors of oxygen saturation and heart rate in the designed photoplethysmography sensor are~1.9%and~2.1%,*** study reveals that water can be used as a high-performance photodetector in informative industries.

关键词： polarization polarized saturation

Text Difficulty Study:Do Machines Behave the Same as Humans Regarding Text Difficulty?

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Machine Intelligence Research 2024年第2期21卷 283-293页

作者： bowen Chen Xiao Ding yi Zhao bo Fu Tingmao Lin Bing Qin Ting liu Research Center for Social Computing and Information Retrieval Harbin Institute of TechnologyHarbin 150001China Fundamental Technology Center China Construction Bank Financial Technology Co.Ltd.Beijing 100033China

With the emergence of pre-trained models,current neural networks are able to give task performance that is comparable to ***,we know little about the fundamental working mechanism of pre-trained models in which we do not know how they approach such performance and how the task is solved by the *** example,given a task,human learns from easy to hard,whereas the model learns ***,difficulty-insensitive learning leads to great success in natural language processing(NLP),but little attention has been paid to the effect of text difficulty in *** propose a human learning matching index(HLM Index)to investigate the effect of text *** results show:1)LSTM gives more human-like learning behavior than ***,UID-SuperLinear gives the best evaluation of text difficulty among four text difficulty *** nine tasks,some tasks’performance is related to text difficulty,whereas others are not.2)Model trained on easy data performs best in both easy and medium test data,whereas trained on hard data only performs well on hard test data.3)Train the model from easy to hard,leading to quicker convergence.

关键词： Cognition inspired natural language processing psycholinguistics explainability text difficulty curriculum learning