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Digital signal acquisition system for complex nuclear reaction experiments

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Nuclear Science and Techniques 2024年第1期35卷 124-133页

作者： Wei-Liang Pu Yan-Lin Ye jian-Ling Lou Jia-Hao chen School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control *** proposed digital system can be combined with a conventional analog data acquisition system to provide more *** performance of the combined system was veri-fied using experimental data.

关键词： Digital signal acquisition system Trigger Programmable logic Timestamp

Effect of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral infarction

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World Journal of Psychiatry 2024年第8期14卷 1190-1198页

作者： fei-fei Liang Xiao-Xia Liu jiang-Hong Liu Yang Gao jian-Guo Dai Zi-Hui Sun Department of Geriatrics Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina The Fourth Ward Zhangjiakou Infectious Disease HospitalZhangjiakou 075000Hebei ProvinceChina Department of Hepatobiliary and Pancreatic Surgery Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina Department of General Medicine Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina

BACKGROUND The aging of the population has become increasingly obvious in recent years,and the incidence of cerebral infarction has shown an increasing trend annually,with high death and disability *** To analyze the effects of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral *** Between January 2020 and December 2023,we treated 98 cases of elderly acute insula,patients with cerebral infarction in the cerebral infarction acute phase(3-4 weeks)and for the course of 6 months in Montreal Cognitive Assessment Scale(MoCA)for screening of ***,58 and 40 patients were placed in the cognitive impairment group and without-cognitive impairment group,*** patients with cerebral infarction,magnetic resonance imaging was used to screen and clearly analyze the MoCA scores of two groups of patients with different infarctions,the relationship between the parts of the infarction volume,and analysis of acute insula cognitive disorder in elderly patients with cerebral RESULTS The number of patients with cognitive impairment in the basal ganglia and thalamus was significantly higher than that without cognitive impairment(P<0.05).The total infarct volume in the cognitive impairment group was higher than that in the non-cognitive impairment group,and the difference was statistically significant(P<0.05).The infarct volumes at different sites in the cognitive impairment group was higher than in the non-cognitive impairment group(P<0.05).In the cognitive impairment group,the infarct volumes in the basal ganglia,thalamus,and mixed lesions were negatively correlated with the total MoCA score,with correlation coefficients of-0.67,-0.73,and-0.77,*** In elderly patients with acute insular infarction,infarction in the basal ganglia,thalamus,and mixed lesions were more likely to lead to cognitive dysfunction than in other areas,and patients with large infarct volumes were more like

关键词： Elderly Acute insular infarction Infarction site Cognitive impairment Infarction volume

Initial precursor reaction mechanism of CVD-HfC coating based on density functional theory

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Chinese Journal of Aeronautics 2024年第7期37卷 511-521页

作者： Yunzhou LIN Yulei ZHANG Yanqin FU jian ZHANG Jing’an KONG Ruicong chen State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research CenterNorthwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Carbon Matrix Composites Research InstituteHenan Academy of SciencesZhengzhou 450046China

Recently,the preparation of ultra-high temperature HfC ceramic coating has gained significant attention,particularly through the application of the HfCl_(4)-CH_(4)-H_(2)-Ar system via Chemical Vapor Deposition(CVD),which has been found widely applied to C/C ***,an analysis of the reactions that occur in the initial stage of the CVD-HfC coating process is presented using Density Functional Theory(DFT)and Transition State Theory(TST)at the B3LYP/Lanl2DZ *** results reveal that HfCl4 can only cleave to produce hypochlorite,which will further react with methyl to synthesize intermediates to form *** to the analysis of the energy barrier and reaction constant,HfCl preferentially reacts with methyl groups to form complex adsorptive intermediates at 1573 *** a C—Hf bond production energy of 212.8 kcal/mol(1 kcal=4.18 kJ),the reaction rate constant of HfCl+CH is calculated to be 2.15×10^(-18) cm^(3)/s at 1573 ***,both the simulation and experimental results exhibit that the upward trend of reaction rate constants with temperature is also consistent with the deposition rate,indicating that the growth curve of the reaction rate constants tends to flatten *** proposed reaction model of the precursor’s decomposition and reconstruction during deposition process has significant implication for the process guidance.

关键词： Carbon composite HfC coating Chemical vapor deposition Density functional theory Precursor reaction mechanism

Inclusions modification by rare earth in steel and the resulting properties: A review

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Journal of Rare Earths 2024年第3期42卷 431-445,I0001页

作者： Xiaoqiang Wang Zhiwei Wu Bing Li Wenxiong chen Jun Zhang jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu610065China chengdu Advanced Metal Materials Industry Technology Research Institute Co. Ltd.Chengdu610303China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

Rare earth(RE) elements are excellent modifiers for non-metallic inclusions that inevitably appear in steel and affect steel properties. This paper reviews the research status of inclusions modification by RE elements and the changes it cause on steel properties. First, the inclusion changes caused by RE modification are described. Generally, after adding pure RE, the main evolution of inclusions occurs as M →M + RE-Al-O → RE-Al-O + RE_(2)O_(2)S → RE_(2)O_(2)S + RE—S/RE_(2)O_(2)S + RE-O with an increase in the RE content(M represents the inclusions before RE addition). The type of final inclusion obtained after RE modification is related to the relative contents of S and O in the steel. Moreover, fine, regular, and uniformly distributed inclusions can be obtained with appropriate RE addition. However, the effectiveness of inclusions modification by adding both RE and non-RE elements is closely related to the order of their addition. Second, the applications and advantages of thermodynamic calculations in the study of RE-modified inclusions are introduced. Third, the changes in the corrosion resistance, impact properties,and other properties of steel caused by the modification of inclusions by RE are reviewed. Finally, the perspectives and trends of inclusions modified by RE elements in the steel industry are presented.

关键词： Rare earths Inclusions Modification Thermodynamic calculation Properties change

Three-dimensional thermohaline structure estimation derived from HY-2 satellite data over the Maritime Silk Road and its applications

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Acta Oceanologica Sinica 2024年第5期43卷 41-53页

作者： Zhiqiang chen Xidong Wang Xiangyu Wu Yuan Cao Zikang He Dakui Wang jian chen Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China Laboratory for Regional Oceanography and Numercial Modeling Qingdao Marine Science and Technology CenterQingdao 266061China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China Beijing Institute of Applied Meteorology Beijing 100029China

Estimated ocean subsurface fields derived from satellite observations provide potential data sources for operational marine environmental monitoring and prediction *** study employs a statistic regression reconstruction method,in combination with domestic autonomous sea surface height and sea surface temperature observations from the Haiyang-2(HY-2)satellite fusion data,to establish an operational quasi-realtime three-dimensional(3D)temperature and salinity products over the Maritime Silk *** products feature a daily temporal resolution and a spatial resolution of 0.25°×0.25°and exhibit stability and *** have demonstrated the accuracy of the reconstructed thermohaline fields in capturing the 3D thermohaline variations through comprehensive statistical evaluations,after comparing them against Argo observations and ocean analysis data from *** results illustrate that the reconstructed fields effectively represent seasonal variations in oceanic subsurface structures,along with structural changes resulting from mesoscale processes,and the upper ocean’s responses to tropical ***,the incorporation of HY-2 satellite observations notably enhances the accuracy of temperature and salinity reconstructions in the Northwest Pacific Ocean and marginally improves salinity reconstruction accuracy in the North Indian Ocean when compared to the World Ocean Atlas 2018 monthly climatology thermohaline *** a result,the reconstructed product holds promise for providing quasi-real-time 3D temperature and salinity field information to facilitate fast decisionmaking during emergencies,and also offers foundational thermohaline fields for operational ocean reanalysis and forecasting *** contributions enhance the safety and stability of ocean subsurface activities and navigation.

关键词： HY-2 satellite observations subsurface structures reconstruction Maritime Silk Road operational thermohaline product

A resonant high-pressure microsensor based on a composite pressure-sensitive mechanism of diaphragm bending and volume compression

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Microsystems & Nanoengineering 2024年第2期10卷 57-66页

作者： Pan Qian Zongze Yu Jie Yu Yulan Lu Bo Xie jian chen Deyong chen Junbo Wang The State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China

In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent *** composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element *** all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency *** microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 *** differential output had an outstanding stability within±0.02 Hz under constant temperature and ***,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.

关键词： stability resonant bending

Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer

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World Journal of Gastroenterology 2024年第18期30卷 2418-2439页

作者： Xiao-Cong Zhou Shi-Wei Guan fei-Yue Ke Gaurav Dhamija Qiang Wang Bang-fei chen Medical University(Wenzhou Central Hospital) Wenzhou 325000Zhejiang ProvinceChina Department of Hepatobiliary Surgery The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Postgraduate Training Base Alliance of Wenzhou Medical University Wenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina School of International Studies Wenzhou Medical UniversityWenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina Department of Radiology The Dingli Clinical Institute of Wenzhou Medical University(Wenzhou Central Hospital)Wenzhou 325000Zhejiang ProvinceChina Department of Colorectal Surgery The Affiliated Zhejiang HospitalZhejiang University School of Medicine(Zhejiang Hospital)Hangzhou 310000Zhejiang ProvinceChina

BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic ***,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical *** To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal *** We retrospectively gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal ***-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)*** difficulty was categorized as either high or low,and multivariate logistic regression analysis was employed to identify predictors of operative difficulty,ultimately creating a *** Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty *** logistic regression analysis showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(P<0.05).Conversely,the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(P<0.05).A nomogram was subsequently constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery.

关键词： Nomogram Rectal cancer Laparoscopic operation Sphincter-preserving surgery Technical difficulty

Molecular-scale co-assembly membranes derived from keplerate cluster:carbonic anhydrase-mimicking nanocapsules for enhanced CO_(2)/N_(2)separation

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Science China Chemistry 2024年第10期67卷 3271-3282页

作者： Wan-Lei Zhao Hongqiang Li Ruoxuan Zheng Yixin Yang Wei chen Yu-fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou 324000China

The development of CO_(2)separation membranes with high permeability and high selectivity,as well as ultra-thin selective layers,has always been ***,a molecular-scaled co-assembly strategy is employed to fabricate the Pebax-Mo_(132)(Pebax=polyether-block-amide copolymer;Mo_(132)=(NH_(4))_(42)[Mo_(72)^(Ⅵ)Mo_(60)^(Ⅴ)O_(372)(CH_(3)COO)_(30)(H_(2)O)_(72)])*** optimal selfstanding membrane,Pebax-Mo_(132)-5%,shows a CO_(2)permeability of~384 Barrer and an ultra-high ideal CO_(2)/N_(2)selectivity of~244,outperforming most membranes reported in the *** CO_(2)permeability and ideal CO_(2)/N_(2)selectivity are increased by 70%and 367%,respectively,compared with the pristine Pebax membrane.A thin-film composite membrane prepared by spin-coating technique on a support membrane with gutter layers also exhibits a CO_(2)permeance of 838 GPU and a CO_(2)/N_(2)selectivity of *** excellent performance can be attributed to the following reasons:(1)strong hydrogen bonding interactions between{Mo_(132)}clusters and Pebax confer excellent interfacial compatibility to the mixed matrix membranes;(2)incorporation of hollow{Mo_(132)}clusters into the Pebax molecular chain decreases the crystallinity of Pebax,and thereby accelerates the chain dynamics and increases the free volume of the membrane;(3)in situ diffuse reflectance infrared Fouriertransform spectroscopy demonstrates that the{Mo_(132)}clusters can effectively catalyze the hydration reaction of CO_(2)and promote the transport of CO_(2);(4)furthermore,the 0.35 nm pores of the crown ether-type{Mo_(9)O_(9)}allow the accurate size sieving of CO_(2)(0.33 nm)and N_(2)(0.36 nm)molecules.

关键词： polyoxometalates molecular-scale assembly CO_(2)capture mixed matrix membranes

Parallel Driving with Big Models and Foundation Intelligence in Cyber-hysical-ocial Spaces

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Research 2024年第2期2024卷 1-17页

作者： Xiao Wang Jun Huang Yonglin Tian chen Sun Lie Yang Shanhe Lou chen Lv Changyin Sun fei-Yue Wang School of Artificial Intelligence Anhui UniversityHefeiChina Macao University of Science and Technology MacaoChina State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijingChina MVSLab Department of Mechanical and Mechatronics EngineeringUniversity of Waterloo200 University Ave WestWaterlooON N2L3G1Canada School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingaporeSingapore

Recent years have witnessed numerous technical breakthroughs in connected and autonomous vehicles (CAVs). On the one hand, these breakthroughs have significantly advanced the development of intelligent transportation systems (ITSs);on the other hand, these new traffic participants introduce more complex and uncertain elements to ITSs from the social space. Digital twins (DTs) provide real-time, data-driven, precise modeling for constructing the digital mapping of physical-world ITSs. Meanwhile, the metaverse integrates emerging technologies such as virtual reality/mixed reality, artificial intelligence, and DTs to model and explore how to realize improved sustainability, increased efficiency, and enhanced safety. More recently, as a leading effort toward general artificial intelligence, the concept of foundation model was proposed and has achieved significant success, showing great potential to lay the cornerstone for diverse artificial intelligence applications across different domains. In this article, we explore the big models embodied foundation intelligence for parallel driving in cyber-physical-social spaces, which integrate metaverse and DTs to construct a parallel training space for CAVs, and present a comprehensive elucidation of the crucial characteristics and operational mechanisms. Beyond providing the infrastructure and foundation intelligence of big models for parallel driving, this article also discusses future trends and potential research directions, and the ?S?goals of parallel driving.

关键词： breakthrough integrate corners