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Corresponding Factors Influencing Crude Oils Assay Using Low-field Nuclear Magnetic Resonance

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China Petroleum Processing & Petrochemical Technology 2014年第2期16卷 34-39页

作者： Feng Yunxia Chu Xiaoli xu yupeng Tian Songbai Research Institute of Petroleum Processing Beijing

In this study, the main factors influencing the measurements by means of the off-line low-field 1H NMR in the lab were discussed base on a robust calibration model established by the PLS algorithm using 255 crude oil samples. The preheating temperature had a great influence on the viscosity of oil samples and the resolution of spectral analysis. The repeatability of spectral measurements was impacted by the metal and wax content of the oil samples. For the case of high wax content oils, the wax species began to crystallize in the course of determination that could affect the repeatability of spectral measurements. These factors have evidenced why the preheating devices and filter unit are necessary when low field NMR system is used in the online analysis process. The investigation is very important for the on-line application of the low field NMR.

关键词： low-field NMR influencing factors crude oils assay

Study on direct point spread function measurement of capillary plate collimators with divergent X-ray beams

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Radiation Detection Technology and Methods 2023年第3期7卷 321-336页

作者： Tianming Li Tao Luo yupeng xu Huilin He Liming Song Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China

Purpose The Filed of View(FOV)of eXTP/LAD is limited by lead-glass capillary plate collimators placed in front of the Silicon Drift Detectors(SDDs)for reducing the background contamination caused by the photons of Cosmic X-ray Background(CXB)leaking from outside the *** core quality parameters of lead-glass capillary plate collimators are Open Area Ratio(OAR)and *** performance of lead-glass capillary plate collimators is determined by its design specification such as pore-to-pore misalignment,pore perpendicularity with collimator surface and pore *** the design specification is the result of a large number of micropores,we use the full width at half maximum(FWHM)and peak value of point spread function(PSF)to characterize the capillary plate collimator *** order to quickly evaluate the performances of collimators,we developed a direct PSF measurement method using divergent *** In this paper,the simulation package of the divergent beamsmeasurement setup is developed based on *** simulation parameters of scintillator absorption length are corrected by experimental *** simulate the PSF of collimators with different distribution of pore diameter and misalignment by parallel beams and divergent *** comparing the peak value and FWHM of collimators PSF,the feasibility in replacing parallel beams measurement with divergent beams measurement is *** It is verified that the influence of the geometric size of 33μm radius of the micro-focus of X-ray tube can be *** results show that the FWHM of collimators is increased with error root mean square error(RMS)of the distribution of collimators pore diameter and pore inclination *** peak value of PSF is mainly influenced by pore non-parallelism of the pores,and it decreases with an increase in pore inclination *** of parallel beams PSF and divergent beams PSF shows well consistency of peak value and FWHM of ***,the peak value of

关键词： Geant4 EXTP/LAD Capillary plate collimators Divergent X-ray beams measurment

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自噬与青光眼视神经病变相关性研究进展

中华实验眼科杂志 2015年第3期33卷 284-288页

作者：许毓鹏许迅上海交通大学附属上海市第一人民医院眼科 200080

青光眼是以视网膜神经节细胞（RGCs）进行性丧失、视盘生理性凹陷扩大、视野缺失为特征的进行性视神经退行性疾病,其神经损伤的确切病变尚未明确.自噬是人体内一条重要的代谢途径,它在降解和循环利用受损细胞器,细胞内大分子物质在维持... 详细信息

青光眼是以视网膜神经节细胞（RGCs）进行性丧失、视盘生理性凹陷扩大、视野缺失为特征的进行性视神经退行性疾病,其神经损伤的确切病变尚未明确.自噬是人体内一条重要的代谢途径,它在降解和循环利用受损细胞器,细胞内大分子物质在维持细胞内稳态方面具有重要作用,并参与多种疾病的发生和发展.近年来对自噬与青光眼的关系研究提示我们,自噬在青光眼视神经病变的转归过程中发挥双刃剑作用,体内有多条代谢通路对自噬过程进行调控,深入理解并利用自噬作用对青光眼视神经病变进行治疗研究具有重要意义.本文就自噬在高眼压、视神经纤维层损伤、视盘重塑、异常蛋白清除以及免疫反应等青光眼视神经病变的发病及其调控机制方面的相关研究进展进行综述.

关键词：自噬/生理青光眼神经变性疾病/生理病理信号通路

Studies of the linearity of the readout module assembling using the eXTP-GPD chips

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Radiation Detection Technology and Methods 2023年第2期7卷 255-262页

作者： Jiechen Jiang Liang Sun Yang Jiao Weichun Jiang yupeng xu Huilin He Xiaohua Liu Yuanyuan Du Sheng Yang Zefang Dong Xiaojing Liu Boyu Dai Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Key Laboratory of Particle Astrophysics Chinese Academy of SciencesBeijing100049China University of Chinese Academy of Sciences Beijing100049China

Background The Gas Pixel Detector(GPD)is a key part of the Polarimetry Focusing Array(PFA)sub-system onboard the enhance X-ray Timing and Polarimetry mission(eXTP).The GPD can accurately provide the polarized angle and degree for incoming soft X-rays(requirements of minimum detectable polarization<1%(10^(6) s,1 mCrab))from celestial objects under extreme conditions of density,gravity and *** Paste the GPD chips on a matched ceramic package is one of the most important procedures for the GPD assembly,and the parallelism between the top surface of an ASIC chip and the bottom surface of a Gas Electron Multiplier(GEM)foil can have impact on the distribution of electric field within transfer region and reconstruction of photoelectric trajectories,resulting in deterioration of the GPD *** study quantifies the influence and gives a reasonable expectation of the *** A simulation framework of the GPD is constructed to quantify the influence on the GPD performance and values of the parallelism are measured by a gauge with a position resolution of o.1μ***:The difference of degree of modulation is less than 1% comparing the parallelism with a value of 20μm to a value of 0μm in response to both polarized and unpolarized ***,the value of parallelism can reach 6.9±3.4μm(0.0176°±0.0087°)by testing and *** The impact on the GPD performance can be less than 1%as the parallelism with an order of 20μm,and we also give a reasonable measuring method and verify the controllability and feasibility of the parallelism with an order of 20μm for pasting the ASIC chip on the surface of a ceramic package.

关键词： Parallelism Gas pixel detectors Gaseous detector simulation Measurements

夫妻共治会改变企业成本粘性吗——基于中国家族上市公司的经验证据

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上海财经大学学报（哲学社会科学版） 2020年第1期22卷 100-122页

作者：许宇鹏上海财经大学会计学院上海200433

夫妻共治会改变企业成本粘性吗?这一问题在夫妻控制家族企业独有的内部治理结构特征下更具有深意。文章基于沪深上市公司中家族企业的数据,从实际控制人的权力配置视角出发,探究夫妻作为实际控制人的权力配置结构对企业成本粘性的影响,... 详细信息

夫妻共治会改变企业成本粘性吗?这一问题在夫妻控制家族企业独有的内部治理结构特征下更具有深意。文章基于沪深上市公司中家族企业的数据,从实际控制人的权力配置视角出发,探究夫妻作为实际控制人的权力配置结构对企业成本粘性的影响,并进一步考察了夫妻共同控制下家族企业内部股权制衡度、夫妻企业家多元化才能特质以及公司治理结构特征等因素对成本粘性的影响。研究结果表明,夫妻共同持股与共同管理的产权配置结构对成本粘性具有显著影响,能够灵活调节成本粘性程度;股权制衡、夫妻企业家多元化才能特质以及妻子具备技术专家型人力资本特质能够显著降低企业的成本粘性。文章对深入理解家族企业内部经营管理特征、提升家族企业管理层决策配置能力和资源配置效率具有启示意义。

关键词：家族企业夫妻共治成本粘性所有权配置管理权配置

Improved Isolation Forest Algorithm for Anomaly Test Data Detection

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Journal of Computer and Communications 2021年第8期9卷 48-60页

作者： yupeng xu Hao Dong Mingzhu Zhou Jun Xing Xiaohui Li Jian Yu China National Tobacco Quality Supervision and Test Center Zhengzhou China Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China University of Science and Technology of China Hefei China

The cigarette detection data contains a large amount of true sample data and a small amount of false sample data. The false sample data is regarded as abnormal data, and anomaly detection is performed to realize the identification of real and fake cigarettes. Binary particle swarm optimization algorithm is used to improve the isolation forest construction process, and isolation trees with high precision and large differences are selected, which improves the accuracy and efficiency of the algorithm. The distance between the obtained anomaly score and the clustering center of the k-means algorithm is used as the threshold for anomaly judgment. The experimental results show that the accuracy of the BPSO-iForest algorithm is improved compared with the standard iForest algorithm. The experimental results of multiple brand samples also show that the method in this paper can accurately use the detection data for authenticity identification.

关键词： Isolation Forest BPSO K-Means Cluster Anomaly Detection

高度近视对眼部结构及视功能影响的研究现状与进展

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中华眼底病杂志 2023年第8期39卷 690-695页

作者：刘尚许毓鹏许迅上海交通大学附属上海市第一人民医院国家眼部疾病临床医学研究中心、上海市眼底病重点实验室、上海眼视觉与光医学工程技术研究中心、上海市临床重点专科上海200080 上海市眼病防治中心/上海市眼科医院上海市视觉健康中心(上海市儿童青少年近视防治技术中心) 上海201103

高度近视具有较高的遗传倾向,其不仅表现在眼轴的过度延长,随着眼轴对眼部结构的机械拉伸还会导致视网膜周围病变、视盘改变、后巩膜葡萄肿及近视性黄斑病变等一系列眼部病变的逐渐形成和进展。高度近视还会导致青光眼、白内障及角膜病... 详细信息

高度近视具有较高的遗传倾向,其不仅表现在眼轴的过度延长,随着眼轴对眼部结构的机械拉伸还会导致视网膜周围病变、视盘改变、后巩膜葡萄肿及近视性黄斑病变等一系列眼部病变的逐渐形成和进展。高度近视还会导致青光眼、白内障及角膜病等疾病的发生风险增加,上述病变将影响视功能,导致日后不可逆的视力损害乃至致盲,因此应重视对视盘改变及后巩膜葡萄肿的筛查,定期监测眼底、眼压及晶状体的变化情况。同时,高度近视可从学习、心理和工作等诸多方面影响个人生活,降低生活质量,增长卫生医疗成本。临床应提高对高度近视的重视程度,从早期开始预防和控制高度近视的发生发展,以求把高度近视对眼部结构及视功能的影响及对个人生活和社会的危害降到最小。

关键词：高度近视眼轴视功能综述

Biogas Production from Anaerobic Digestion of High Oil Waste

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Meteorological and Environmental Research 2017年第2期8卷 54-58页

作者： Cheng Xiaowei Zhu Hongguang Zhang Tao Li Ling xu yupeng Peng Shengnan Bio-Energy Research Center Institute of New Rural DevelopmentTongji UniversityShanghai 201804China

The possibility of anaerobic digestion of high oil waste at high temperatures was explored,and the effects of fat concentration on biogas production via anaerobic digestion were analyzed by batch and continuous experiments successively. Besides,the response and recovery of the digestion system to the shock of high concentrations of oil were studied. The results showed that the anaerobic digestion of high oil waste could be carried out,and fat concentration had a significant effect on the anaerobic digestion. In the batch experiments,the process of anaerobic digestion could carry out only when fat concentration was 0-1. 68%,and the average methane content was 46. 42%; with the increase of fat concentration,both methane content and production rate decreased significantly,and the digestion period was extended obviously. When fat concentration exceeded 2. 52%,the anaerobic digestion failed to start,and methane could not be detected in the produced biogas. In the continuous experiments,the system could withstand a certain concentration of fat( 6 g/L),and anaerobic digestion process would be inhibited when it experienced the impact of a high oil load( 26. 7 g/L). Nevertheless,this process could recover quickly after the removal of the impact,and the system could withstand a higher fat concentration( 13 g/L) than before. Furthermore,the volume production rate of biogas was approximately 1 L/( L·d),and methane content was about 55%.

关键词： High oil waste Biogas Anaerobic digestion China

In-orbit performance of ME onboard Insight-HXMT in the first 5 years

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Radiation Detection Technology and Methods 2023年第1期7卷 15-24页

作者： Ying Tan xuelei Cao Weichun Jiang Xiaobo Li Bin Meng Wanchang Zhang Sheng Yang Tao Luo Yudong Gu Liang Sun Xiaojing Liu Yuanyuan Du Jiawei Yang Yanjun xu Jinyuan Liao yupeng xu Fangjun Lu Liming Song Shuangnan Zhang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Science19B Yuquan RoadShijingshan DistrictBeijing 100049China

Introduction The medium-energy X-ray telescope(ME)is a collimated X-ray telescope onboard the Insight hard X-ray modulation telescope(Insight-HXMT)*** has 1728 Si-PIN pixels readout using 54 low noise application-specific integrated circuits(ASICs).ME covers the energy range of 5–30 keV and has a total detection area of *** typical energy resolution of ME at the beginning of the mission is 3 keV at 17.8 keV(full width at half maximum,FWHM),and the time resolution is 255μ*** this study,we present the in-orbit performance of ME in its first 5 years of *** The performance of ME was monitored using onboard radioactive sources and astronomical X-ray *** carries six 241Am radioactive sources for onboard calibration,which can continuously illuminate the calibration *** long-term performance evolution of ME can be quantified using the properties of the accumulated spectra of the calibration *** addition,observations of the Crab Nebula and the pulsar were used to check the long-term evolution of the detection efficiency as a function of *** After 5 years of operation,742cm2 of the Si-PIN pixelswere stillworking *** peak positions of 241Am emission lines gradually shifted to the high-energy region,implying a slow increase in ME gain of 1.43%.A comparison of the ME spectra of the Crab Nebula and the pulsar shows that the E–C relations and the redistribution matrix file are still acceptable for most data analysis works,and there is no detectable variation in the detection efficiency.

关键词： Hard X-ray Calibration Detector In-orbit performance