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

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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 sensors.For 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 measurements.This may introduce significant errors,particularly in proton spot scanning radiotherapy.In 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 resolution.Meanwhile,the similarity between the measured original data and the downsampled logfilebased reconstructed dose is regarded as the confidence of the reformatted dose distribution.Furthermore,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 measurements.The 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 measurements.The 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

Surface modification of MCM-41 and its application in DNA adsorption

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Chinese Chemical Letters 2016年第1期27卷 139-144页

作者： xiu-Yu Sun Peng-Zhang Li Bing Ai yue-Bo Wang School of Chemical Engineering Shandong University of Technology

Three types of MCM-41 absorbents, namely, Al^（3＋）-MCM-41, La^（3＋）-MCM-41, and Zn^（2＋）-MCM-41, were prepared through amine grafting, phosphonate modification, and metal ion chelation and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and N2adsorption-desorption analysis. Results revealed that functionalized MCM-41 maintains the original structure of the molecular sieve and that the pore diameter and surface area are reduced compared with those of pure MCM-41. The adsorption behavior of DNA molecules on the surface of the modified molecular sieves was discussed according to the hard-soft acid-base（HSAB） principle. Experimental results showed that DNA purification could be effectively carried out on functionalized MCM-41 and that DNA is easily released by3-4 molL^（-1）NaCl solution. This study could be used as a general platform for future work on DNA adsorption and enrichment.

关键词： MCM-41 Surface modification DNA Adsorption

Photodegradation of amoxicillin by catalyzed Fe^(3+)/H_2O_2 process

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Journal of Environmental Sciences 2012年第2期24卷 269-275页

作者： Xiaoming Li Tingting Shen Dongbo Wang Xiu Yue Xian Liu Qi Yang Jianbin Cao Wei Zheng Guangming Zeng College of Environmental Science and Engineering Hunan University Changsha 410082 China. Key Laboratory of Environmental Biology and Pollution Control Hunan University Ministry of Education Changsha 410082 China School of Environment Guangxi University Nanning 530004 China

Three oxidation processes of UV-Fe3＋（EDTA）/H2O2（UV：ultraviolet light;EDTA：ethylenediaminetetraacetic acid）,UV-Fe3＋/H2O2 and Fe3＋/H2O2 were simultaneously investigated for the degradation of amoxicillin at pH 7.0.The results indicated that,100% amoxicillin degradation and 81.9% chemical oxygen demand（CODCr） removal could be achieved in the UV-Fe3＋（EDTA）/H2O2 process.The treatment efficiency of amoxicillin and CODCr removal were found to decrease to 59.0% and 43.0% in the UV-Fe3＋/H2O2 process;39.6% and 31.3% in the Fe3＋/H2O2 process.Moreover,the results of biodegradability（biological oxygen demand（BOD5）/CODCr ratio） revealed that the UV-Fe3＋（EDTA）/H2O2 process was a promising strategy to degrade amoxicillin as the biodegradability of the effuent was improved to 0.45,compared with the cases of UV-Fe3＋/H2O2（0.25） and Fe3＋/H2O2（0.10） processes.Therefore,it could be deduced that EDTA and UV light performed synergetic catalytic effect on the Fe3＋/H2O2 process,enhancing the treatment efficiency.The degradation mechanisms were also investigated via UV-Vis spectra,and high performance liquid chromatography-mass spectra.The degradation pathway of amoxicillin was further proposed.

关键词： amoxicillin catalytic oxidation photodegradation

Relationship of Microvascular Obstruction with Global and Regional Myocardial Function Determined by Cardiac Magnetic Resonance after ST-Segment Elevation Myocardial Infarction

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Chinese Medical Sciences Journal 2023年第1期38卷 11-19页

作者： Ya-Nan Zhao Jia-Ning Cui Xing-Hua Zhang Jin-Feng Li Shi-Min Chen xiu-Zheng yue Tao Li Department of Radiology First Medical Center of Chinese People’s Liberation Army General HospitalBeijing 100853China Department of Epidemiology and Statistics graduate school of Chinese People’s Liberation Army General HospitalBeijing 100853China Philips Healthcare Beijing 100600China

Objective To investigate the impact of microvascular obstruction(MVO)on the global and regional myocardial function by cardiac magnetic resonance feature-tracking(CMR-FT)in ST-segment-elevation myocardial infarction(STEMI)patients after percutaneous coronary intervention.Methods Consecutive acute STEMI patients who underwent cardiac magnetic resonance imaging 1-7 days after successful reperfusion by percutaneous coronary intervention treatment were included in this retrospective study.Based on the presence or absence of MVO on late gadolinium enhancement images,patients were divided into groups with MVO and without MVO.The infarct zone,adjacent zone,and remote zone were determined based on a myocardial 16-segment model.The radial strain(RS),circumferential strain(CS),and longitudinal strain(LS)of the global left ventricle(LV)and the infarct,adjacent,and remote zones were measured by CMRFT from cine images and compared between patients with and without MVO using independent-samples t-test.Logistic regression analysis was used to assess the association of MVO with the impaired LV function.Results A total of 157 STEMI patients(mean age 56.66±11.38 years)were enrolled.MVO was detected in 37.58%(59/157)of STEMI patients,and the mean size of MVO was 3.00±3.76 mL.Compared with patients without MVO(n=98),the MVO group had significantly reduced LV global RS(t=-4.30,P<0.001),global CS(t=4.99,P<0.001),and global LS(t=3.51,P=0.001).The RS and CS of the infarct zone in patients with MVO were significantly reduced(t=-3.38,P=0.001;t=2.64,P=0.01;respectively)and the infarct size was significantly larger(t=8.37,P<0.001)than that of patients without MVO.The presence of LV MVO[OR=4.10,95%CI:2.05-8.19,P<0.001]and its size[OR=1.38,95%CI:1.10-1.72,P=0.01],along with the heart rate and LV infarct size were significantly associated with impaired LV global CS in univariable Logistic regression analysis,while only heart rate(OR=1.08,95%CI:1.03-1.13,P=0.001)and LV infarct size(OR=1.10,95%CI:1.03-1.16,P=0.003)were independent influencing fa

关键词： cardiac magnetic resonance feature tracking ST-segment elevation myocardial infarction microvascular obstruction myocardial strain Myocardial function

Microscale endometrial sampling biopsy in detecting endometrial cancer and atypical hyperplasia in a population of 1551 women:a comparative study with hysteroscopic endometrial biopsy

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Chinese Medical Journal 2021年第2期134卷 193-199页

作者： Guo Zhang yue Wang Xu-Dong Liang Rong Zhou xiu-Li Sun Jian-Liu Wang Li-Hui Wei Department of Gynecology and Obstetrics Peking University People’s HospitalBeijing 100044China

Background:Endometrial cancer is one of the most common malignancies of the reproductive system.Effective and cost-effective screening method for populations at high risk is not available.This study aimed to investigate specimen adequacy and the influencing factors in microscale endometrial sampling biopsy and to evaluate the diagnostic accuracy and medical cost of biopsy in endometrial cancer and atypical hyperplasia screenings in comparison with hysteroscopic endometrial biopsy.Methods:A total of 1551 patients at high risk for endometrial lesions who required hysteroscopic endometrial biopsy from November 2017 to August 2018 were included.Microscale endometrial sampling biopsy was performed,followed by hysteroscopic endometrial biopsy.We evaluated the specimen adequacy and influencing factors of microscale endometrial sampling.Diagnostic consistency between microscale endometrial sampling biopsy and hysteroscopic endometrial biopsy was evaluated.The sensitivity,specificity,positive predictive value,and negative predictive value of microscale endometrial sampling biopsy in screening for endometrial cancer and atypical hyperplasia were analyzed,and the medical costs of the two procedures were compared.Results:The specimen adequacy was 81.2%.Patient age,menopausal status,endometrial thickness,and endometrial lesion type were correlated with specimen adequacy.There was good consistency in distinguishing benign and malignant endometrial diseases between microscale endometrial sampling biopsy and hysteroscopic biopsy(kappa 0.950,95%CI 0.925-0.975).The sensitivity,specificity,positive predictive value,and negative predictive value of microscale endometrial sampling biopsy were 91.7%,100.0%,100.0%,and 99.3%for endometrial cancer screening,respectively,and 82.0%,100.0%,100.0%,and 99.4%for atypical hyperplasia screening.The medical cost of endometrial sampling biopsy was only 22.1%of the cost of hysteroscopic biopsy.Conclusions:Microscale endometrial sampling biopsy is a minimally invasive alternative technique for obtai

关键词： Endometrial atypical hyperplasia Endometrial cancer Hysteroscopic endometrial biopsy Microscale endometrial sampling biopsy

Mathematical model of coupled thermo-mechanical behavior during plane strain compression of 06Cr19Ni9NbN steel

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Journal of Iron and Steel Research(International) 2018年第11期25卷 1179-1188页

作者： Yong-xing Jiao yue Xu Jian-sheng Liu Jing-dan Li xiu-zhi Zhang College of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024ShanxiChina

The process of plane strain compression of 06Cr19Ni9NbN steel was carried out in the temperature range of 1000-1200℃ and the reduction ratio range of 10-50%.Combining the finite element numerical simulation,a new constitutive model of thermal deformation was established, which provides the theoretical basis to optimize the plarie strain compression process of the steel.The temperature and grain size at different regions were achieved by experiment and simulation,respectively.According to the results,the mathematical models of stress and temperature during the plane strain compression were established by mathematical analysis method.The new temperature models were established in three regions,respectively,and the stress models took account of the variation of temperature and'st^rain rate.Finally,by comparing the results of calculation,numerical simulation and experiment,the accuracy and validity of these mathematical models were verified.

关键词： Plane strain compression Coupled thermo-mechanical behavior 06Cr19Ni9NbN steel Numerical simulation Mathematical model

Finite-difference model of land subsidence caused by cluster loads in Zhengzhou,China

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Journal of Groundwater Science and Engineering 2020年第1期8卷 43-56页

作者： ZHAO yue-wen WANG xiu-yan LIU Chang-li LI Bing-yan Institute of hydrogeology and environmental geology Chinese academy of geological sciences

Groundwater exploitation has been regarded as the main reason for land subsidence in China and thus receives considerable attention from the government and the academic community.Recently,building loads have been identified as another important factor of land subsidence,but researches in this sector have lagged.The effect of a single building load on land subsidence was neglected in many cases owing to the narrow scope and the limited depth of the additional stress in stratum.However,due to the superposition of stresses between buildings,the additional stress of cluster loads is greater than that of a single building load under the same condition,so that the land subsidence caused by cluster loads cannot be neglected.Taking Shamen village in the north of Zhengzhou,China,as an example,a finite-difference model based on the Biot consolidation theory to calculate the land subsidence caused by cluster loads was established in this paper.Cluster loads present the characteristics of large-area loads,and the land subsidence caused by cluster loads can have multiple primary consolidation processes due to the stress superposition of different buildings was shown by the simulation results.Pore water migration distances are longer when the cluster loads with high plot ratio are imposed,so that consolidation takes longer time.The higher the plot ratio is,the deeper the effective deformation is,and thus the greater the land subsidence is.A higher plot ratio also increases the contribution that the deeper stratigraphic layers make to land subsidence.Contrary to the calculated results of land subsidence caused by cluster loads and groundwater recession,the percentage of settlement caused by cluster loads in the total settlement was 49.43%and 55.06%at two simulated monitoring points,respectively.These data suggest that the cluster loads can be one of the main causes of land subsidence.

关键词： Land subsidence Cluster loads Additional stress Fluid-solid coupling model Finite-difference model

Self-lubricating CrVN Coating Strengthened via Multilayering with VN

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Journal of Iron and Steel Research(International) 2014年第5期21卷 545-550页

作者： yue-xiu QIU Bo LI Jyh-wei LEE Dong-liang ZHAO Central Iron and Steel Research Institute Advanced Technology and Materials Co. Ltd. Department of Materials Engineering Ming Chi University of Technology Center for Thin Film Technologies and Applications Ming Chi University of Technology

To improve the mechanical properties of self-lubricating chromium vanadium nitride （CrVN） coatings, va- nadium nitride （VN） is combined with CrVN to form multilayered CrVN/VN coatings through an in-line magnetron sputtering system. The strengthening effect of the period thickness on the mechanical and tribological properties is studied. X-ray diffractometer, low-angle X-ray reflectivity, scanning electron microscopy, atomic force microscopy, electron probe micro-analyzer and X-ray photoelectron spectroscopy are employed to characterize the microstructures and chemical composition. Nanoindentation and ball-on-disc tribo-tester are used in characterization of the mechanical and tribological properties. The CrVN/VN multilayer coatings demonstrate good lubrication property with coefficient of friction down to 0.23. Multilayering with VN, the hardness of CrVN jumps to 27.6 GPa with period thickness of 6 nm, which has an improvement of 5.1 GPa compared with that of 22.5 GPa from rule-of-mixture.

关键词： CrVN/VN multilayered coating mechanical property self-luhricating magnetron sputtering

Inequalities on the Inner Radius of Univalency and the Norm of Pre-Schwarzian Derivative

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Acta Mathematica Sinica,English Series 2009年第1期25卷 59-64页

作者： Tao CHENG yue Ming KANG Ji xiu CHEN Academy of Mathematics and Systems Science CAS Beijing 100190 P. R. China Department of Mathematics Jiangxi Normal University Nanchang 330027 P. R. China Business Information Management School Shanghai Institute of Foreign Trade Shanghai 201600 P. R. China School of Mathematical Sciences Fudan University Shanghai 200433 P. R. China

In this paper, we get a lower bound of inner radius of univalency of Schwarzian derivative by means of the norm of pre-Schwarzian derivative. Furthermore, we apply the theory of Universal Teichmuller Space to explain its geometric meaning which shows the relationship between the inner radius in Universal Teichmuller Space embedded by Schwarzian derivative and the norm defined in Universal Teichmuller Space embedded by pre-Schwarzian derivative.

关键词： Pre-Schwarzian derivative inner radius of univalency Universal Teichmuller Space