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Nuclear Science and Techniques 2005年第4期16卷 238-243页

作者： ZHU Jie LIU Shi-Tao LEI Xiao-Wen yan Tian-xin xu Zi-Zong WANG Zhao-Min Department of Modern Physics University of Science and Technology of China Hefei 230026

The performance of gamma camera with NaI(Tl) array coupled with position sensitive photomultiplier tube (PSPMT) R2486 has been studied. The pixel size of NaI(Tl) crystal is 2mm×2mm and the overall dimension of the array is 48.2mm×48.2mm×5mm. There are 484 pixels in a 22×22 matrix. Because each pixel can produce a much focused light spot and restrict the spread of photons, position resolution of the gamma camera is mainly determined by pixel size. It is shown that crystal array pixel can reduce shrinkage effect and improve intrinsic position resolution greatly via restricting the spread of photons. Experimental results demonstrate that its position resolution and linearity are much improved comparing with the gamma camera using planar crystals coupled with PSPMT.

关键词：光电倍增器像素照相机 PSPMT 线性关系

Performance of multigap resistive plate chamber in a γ-ray aging test

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Nuclear Science and Techniques 2006年第5期17卷 293-296页

作者： WU Yue-Lei WANG Xiao-Lian ZOU Tao ZHAO yan-E DONG xin xu Zi-Zong Department of Modern Physics University of Science ＆ Technology of China Hefei 230026 China

The aging test of multigap resistive chamber (MRPC) was carried out under conditions of irradiation from a 137Cs γ source facility. The total charge induced at the anode or at the cathode of the MRPC module was about 29 mC. The gamma dose rate was 10-2 Gy·h-1, and the total accumulative radiation dose was 4.3 Gy. After irradiation, there was an obvious degradation in the properties of the MRPC module.

关键词： γ射线辐照老化试验辐照剂量气体检测器 MRPC

High-performance Ti_(3)C_(2)T_(x)achieved by polyaniline intercalation and gelatinization as a high-energy cathode for zinc-ion capacitor

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Nano Research 2024年第6期17卷 5305-5316页

作者： Peng Liao ZiYu Geng xin Zhang Wenjie yan Zenghui Qiu Haijun xu College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China

The actual manufacture of supercapacitors(SCs)is restricted by the inadequate energy density,and the energy density of devices can be properly promoted by assembling zinc-ion capacitors(ZICs)which used capacitive cathode and battery-type ***-dimensional(2D)MXene has brought great focuses in the electrode research on the foundation of large redox-active surface,but the specific capacitance is still affected by the tight stacking of ***_(3)C_(2)T_(x)@polyaniline(PANI)heterostructures are prepared by uniformly depositing the conductive polymer PANI nanorods as the intercalation agent into the external of Ti_(3)C_(2)T_(x)nanosheets to inhibit ***,by using graphene oxide(GO)-assisted low-temperature hydrothermal self-assembly manufacture,2D heterostructures are assembled into the three-dimensional(3D)porous crosslinked Ti_(3)C_(2)T_(x)@PANI-reduced graphene oxide(RGO)*** to the synergistic work of PANI nanorods,Ti_(3)C_(2)T_(X)nanosheets,and 3D crosslinking frameworks of RGO to match capacitive and battery effects,3D porous hierarchical Ti_(3)C_(2)T_(x)@PANI-RGO heterostructure hydrogels have rich ion transport channels,a large number of active sites,and excellent reaction *** is assembled by using Ti_(3)C_(2)T_(x)@PANI-RGO heterostructure hydrogels as cathodes and zinc foil as *** this work,Ti_(3)C_(2)T_(x)@PANI-RGO//Zn ZIC exhibits a wide working window(2.0 V),marked specific capacitance(589.89 F·g^(−1)at 0.5 A·g−1),salient energy density(327.71 Wh·kg^(−1)at 513.61 W·kg^(−1)and 192.20 Wh·kg^(−1)at 13,005.87 W·kg^(−1)),and durable cycling stability(97.87%capacitance retention after 10,000 cycles at 10 A·g^(−1)).This study emphasizes the device design of ZICs and the broad prospect of Ti_(3)C_(2)T_(x)-based hydrogels as viable cathodes for ZICs.

关键词： polyaniline(PANI) Ti_(3)C_(2)T_(x)@PANI heterostructure intercalation process three-dimensional(3D)porous hydrogel high energy density zinc-ion capacitor

Nickel-catalyzed carbonylative four-component 1,4-dicarbofunctionalization of 1,3-enynes

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Science China Chemistry 2024年第6期67卷 2029-2038页

作者： yan Zhao Qi-Chao Shan Hong xin Pin Gao xu yang xin-Hua Duan Li-Na Guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy StorageMaterials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China

An efficient Ni-catalyzed four-component 1,4-carbocarbonylation of 1,3-enynes with activated alkyl halides and arylboronic acids under atmospheric pressure of CO is *** tuning the electronic and steric effects of alkyl radicals,both electronrich and electron-deficient 1,3-enynes were compatible with this *** protocol features mild conditions,broad substrate scope,excellent functional group compatibility and facile gram-scale synthesis,providing a practical approach to the quaternary carbon center-containing allenyl *** study revealed that the acyl-NiIIspecies plays an important role in both the coupling and the alkyl radical generation processes.

关键词： Ni catalysis four-component 1 4-carbocarbonylation 1 3-enynes

An Integral Method for Solving Dynamic Equations with Fluid–Solid Coupling

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Acta Mechanica Solida Sinica 2024年第1期37卷 99-108页

作者： xin Zhang Jie Liu Pu xue Shuowen yan Yahao xu M.S.Zahran School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Civil Engineering Military Technical CollegeCairo 11435Egypt

In this work,a new methodology is presented to mainly solve the fluid–solid interaction(FSI)*** methodology combines the advantages of the Newmark precise integral method(NPIM)and the dual neural network(DNN)*** NPIM is employed to modify the exponential matrix and loading vector based on the DNN integral *** involves incorporating the basic assumption of the Newmark-βmethod into the dynamic equation and eliminating the acceleration term from the dynamic equilibrium *** a result,the equation is reduced to a first-order linear equation ***,the PIM is applied to integrate the system step by step within the *** DNN method is adopted to solve the inhomogeneous term through fitting the integrand and the original function with a pair of neural networks,and the integral term is solved using the Newton–Leibniz *** examples demonstrate that the proposed methodology significantly improves computing efficiency and provides sufficient precision compared to the DNN *** is particularly evident when analyzing large-scale structures under blast loading conditions.

关键词： Newmark precise integral method(NPIM) Dual neural networks(DNN) Fluid-solid interaction(FSI) Dynamic time-history analysis Blast loading

Influence of transcatheter arterial embolization on symptom distress and fatigue in liver cancer patients

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 810-818页

作者： xu-Min yang xu-yan yang xin-Yu Wang Yue-Xia Gu Department of Nursing The First Affiliated Hospital of Naval Medical University(Changhai Hospital)Shanghai 200433China Department of Thyroid Breast and Vascular SurgeryShanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200434China Department of Nursing Shanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200434China

BACKGROUND Hepatocellular carcinoma(HCC)is a prevalent malignancy,and transcatheter arterial embolization(TAE)has emerged as a pivotal therapeutic ***-ever,TAE may induce symptom distress and fatigue,adversely affecting the quality of life of *** To investigate symptom distress,fatigue,and associated factors in HCC patients undergoing *** We used a cross-sectional design and purposive sampling to enroll HCC patients who underwent TAE at our institution from January to December ***-naires were utilized to collect data on symptom distress and fatigue scores from the first to the third day after *** Our study revealed a significant reduction in fatigue and symptom distress among patients after ***,fatigue,insomnia,fever and abdominal dis-tension were the most common symptoms troubling patients during the first 3 d *** status,presence of family support,physical functional status,age,and symptom distress were identified as predictors of fatigue in *** Healthcare professionals should educate HCC patients on symptom distress and INTRODUCTION Hepatocellular carcinoma(HCC)ranks as the fifth most prevalent cancer and the third leading cause of cancer-related mortality *** intervention remains the cornerstone of HCC treatment;however,due to the challenges associated with early diagnosis and the lack of specific diagnostic markers,a considerable proportion of patients are diagnosed at advanced stages,rendering them ineligible for surgical *** arterial embolization(TAE)is an interventional therapeutic approach involving the insertion of a fine catheter via the femoral artery to reach the vasculature near the tumor *** aims to obstruct the arterial supply to the tumor by deploying embolic agents,thereby inducing necrosis in cancer *** procedure is suitable for patients with good liver function and overall health,particularly those with large HCCs that ha

关键词： Transcatheter arterial embolization Fatigue Symptom distress Hepatocellular carcinoma Influencing factors

Rotating Massive Strangeon Stars and X-Ray Plateau of Short GRBs

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Research in Astronomy and Astrophysics 2024年第3期24卷 47-57页

作者： Xi-yan yang Xiao-Yu Lai Wei-Wei Tan Ren-xin xu School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhou 434023China Research Center for Astronomy Hubei University of EducationWuhan 4300205China Key Laboratory of Quark and Lepton Physics Central China Normal UniversityMinistry of EducationWuhan 430079China School of Physics Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Strangeon stars,which are proposed to describe the nature of pulsar-like compact stars,have passed various observational *** maximum mass of a non-rotating strangeon star could be high,which implies that the remnants of binary strangeon star mergers could even be long-lived massive strangeon *** study rigidly rotating strangeon stars in the slowly rotating approximation,using the Lennard-Jones model for the equation of *** can significantly increase the maximum mass of strangeon stars with unchanged baryon numbers,enlarging the mass-range of long-lived strangeon *** spin-down after merger,the decrease of radius of the remnant will lead to the release of gravitational *** into account the efficiency of converting the gravitational energy luminosity to the observed X-ray luminosity,we find that the gravitational energy could provide an alternative energy source for the plateau emission of X-ray *** fitting results of X-ray plateau emission of some short gamma-ray bursts suggest that the magnetic dipole field strength of the remnants can be much smaller than that of expected when the plateau emission is powered only by spin-down luminosity of magnetars.

关键词： dense matter-(stars) pulsars general-(stars) gamma-ray burst general

Review on analytical technologies and applications in metabolomics

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BIOCELL 2024年第1期48卷 65-78页

作者： xin MENG yan LIU SHUJUN xu LIANRONG yanG RUI YIN School of Pharmacy Heilongjiang University of Chinese MedicineHarbinChina

Over the past decade,the swift advancement of metabolomics can be credited to significant progress in technologies such as mass spectrometry,nuclear magnetic resonance,and multivariate ***,metabolomics garners widespread application across diverse fields including drug research and development,early disease detection,toxicology,food and nutrition science,biology,prescription,and chinmedomics,among *** serves as an effective characterization technique,offering insights into physiological process alterations in *** changes may result from various exogenous factors like environmental conditions,stress,medications,as well as endogenous elements including genetic and protein-based *** potential scientific outcomes gleaned from these insights have catalyzed the formulation of innovative methods,poised to further broaden the scope of this ***,metabolomics has evolved into a valuable and widely accepted instrument in the life ***,comprehensive reviews focusing on the sample preparation and analytical methodologies employed in metabolomics within the life sciences are surprisingly *** review aims to fill that gap,providing an overview of current trends and recent advancements in *** emphasis is placed on sample preparation,sophisticated analytical techniques,and their applications in life science research.

关键词： Metabolomics Sample preparation Analytical methods Application of metabolomics

Vitreoretinal surgeons'experience and time interval from pars-plana vitrectomy to cataract extraction

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International Journal of Ophthalmology(English edition) 2021年第1期14卷 120-126页

作者： yan-xin xu Liang-Ping Liu Jian-Bing Li Huan-Huan Cheng Min Hou Lin Lu Ming-xing Wu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina

AIM:To identify the association of the vitreoretinal surgeons'experience with the time interval between parsplana vitrectomy(PPV)and cataract extraction(CE).METHODS:Eyes with prior PPV and following CE were included in this retrospective cohort *** years of practice and the annual case volume were used to describe the surgeons'*** linear regression analysis was used to investigate the relationship between surgeons'experience and the time interval adjusted for the patients age,gender,intraocular tamponade,and case ***:Of 132430 eyes,1445 eyes were included in this *** multivariable linear regression analysis,cases performed by surgeons with>20 practice years had longer time intervals compared with surgeons with<10 practice years after adjusted for other variables(β=0.329,95%CI:0.113 to 0.549,P=0.003).No difference in time interval was detected for comparing the lowest with the highest volume groups(β=0.089,95%CI:-0.164 to 0.343,P=0.343).The surgeons'practice years were not directly with the *** complicated surgery,the higherpractice-year surgeons had longer time interval than lowerpractice-year ***:The time intervals from PPV to CE is longer in higher-practice-year *** surgeons'practice years may have a greater effect on the time interval than annual case volume in high-complexity *** the complexity of vitreoretinal diseases with the surgeons'practice year should be considered.

关键词： pars-plana vitrectomy cataract time interval experience annual case volume

Microscopic nonlinear optical activities and ultrafast carrier dynamics in layered AgInP_(2)S_(6)

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Photonics Research 2024年第4期12卷 691-700页

作者： ZIxin WANG NINGNING DONG YU MAO CHENDUAN CHEN xin CHEN CHANG xu ZHOUYUAN yan JUN WANG Aerospace Laser Technology and Systems Department CAS Key Laboratory of Materials for High-Power LaserShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Ultra-intense Laser Science(CEULS) State Key Laboratory of High Field Laser PhysicsShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

Since the emergence of graphene, transition metal dichalcogenides, and black phosphorus, two-dimensional materials have attracted significant attention and have driven the development of fundamental physics and optoelectronic devices. Metal phosphorus trichalcogenides(MPX3), due to their large bandgap of 1.3–3.5 eV, enable the extension of optoelectronic applications to visible and ultraviolet(UV) wavelengths.

关键词： nonlinear ultraviolet phosphorus