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Counting of alpha particle tracks on imaging plate based on a convolutional neural network

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Nuclear Science and Techniques 2023年第3期34卷 52-63页

作者： Feng-Di Qin Han-Yu Luo zheng-Zhong He Ke-Jun Lu chuan-Gao Wang Meng-Meng Wu Zhong-Kai Fan jian Shan School of Nuclear Science and Technology Hunan Provincial Key Laboratory of RadonUniversity of South ChinaHengyang 421001China School of Computer Science University of South ChinaHengyang 421001China China Institute of Atomic Energy Beijing 102413China

Imaging plates are widely used to detect alpha particles to track information,and the number of alpha particle tracks is affected by the overlapping and fading effects of the track *** this study,an experiment and a simulation were used to calibrate the efficiency parameter of an imaging plate,which was used to calculate the *** were created by using grayscale,which trained the convolutional neural network to count the alpha *** results demonstrated that the trained convolutional neural network can evaluate the alpha track counts based on the source and background images with a wider linear range,which was unaffected by the overlapping *** alpha track counts were unaffected by the fading effect within 60 min,where the calibrated formula for the fading effect was analyzed for 132.7 *** detection efficiency of the trained convolutional neural network for inhomogeneous ^(241)Am sources(2π emission)was 0.6050±0.0399,whereas the efficiency curve of the photo-stimulated luminescence method was lower than that of the trained convolutional neural network.

关键词： Imaging plate Convolutional neural network Alpha tracks counting

Ambarzumyan's Theorem for the Dirac Operator on Equilateral Tree Graphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 568-576页

作者： Dong-Jie WU Xin-jian XU chuan-Fu YANG Department of Mathematics School of Mathematics and StatisticsNanjing University of Science and TechnologyNanjing 210094China

The classical Ambarzumyan’s theorem states that if the Neumann eigenvalues of the Sturm-Liouville operator-d^(2)/dx^(2)+q with an integrable real-valued potential q on[0,π] are {n^(2):n≥0},then q=0 for almost all x∈[0,π].In this work,the classical Ambarzumyan’s theorem is extended to the Dirac operator on equilateral tree *** prove that if the spectrum of the Dirac operator on graphs coincides with the unperturbed case,then the potential is identically zero.

关键词： dirac operator quantum graph Ambarzumyan’s theorem inverse spectral problem

Multiple liver metastases of unknown origin:A case report

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 233-238页

作者： Ying-Jin Wang Ze-chuan Liu jian Wang Yin-Mo Yang Department of Hepatobiliary Pancreatic Surgery Peking University First HospitalBeijing 100034China Department of Interventional and Vascular Surgery Peking University First HospitalBeijing 100034China

BACKGROUND The liver is the most common site of digestive system tumor metastasis,but not all liver metastases can be traced back to the primary *** it is unusual,syphilis can impact the liver,manifesting as syphilitic hepatitis with inflammatory nodules,which might be misdiagnosed as *** SUMMARY This case report involves a 46-year-old female who developed right upper abdominal pain and intermittent low fever that persisted for more than three *** definitive diagnosis of a tumor had been made in the past decades,but signs of multiple liver metastases were recognized after a computed tomo-graphy scan without evidence of primary *** positive serological tests for syphilis and a biopsy of the liver nodules,a diagnosis of hepatic syphilis was made and confirmed with follow-up nodule reduction after anti-syphilis *** Clinicians must be aware of the possibility that syphilis can cause hepatic inflam-matory masses,especially when liver metastasis is suspected without evidence of primary lesions.A definitive diagnosis should be established in conjunction with a review of the patient’s medical history for accurate therapeutic intervention.

关键词： Syphilitic hepatitis Liver nodules Liver metastasis Treponema pallidum Case report

In Situ Observation of Gypsum-Anhydrite Transition at High Pressure and High Temperature

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Chinese Physics Letters 2012年第4期29卷 252-255页

作者： LIU chuan-jiang zheng Hai-Fei Key Laboratory of Orogenic Belts and Crustal Evolution(Ministry of Education) Peking UniversityBeijing 100871 Institute of Geochemistry Peking UniversityBeijing 100871

An in-situ Raman spectroscopic study of gypsum-anhydrite transition under a saturated water condition at high pressure and high temperature is performed using a hydrothermal diamond anvil cell (HDAC).The experimental results show that gypsum dissolvs in water at ambient temperature and above 496 *** increasing temperature,the anhydrite (CaSO4) phase precipitates at 250 320℃ in the pressure range of 1.0 1.5 GPa,indicating that under a saturated water condition,both stable conditions of pressure and temperature and high levels of Ca and SO4 ion concentrations in aqueous solution are essential for the formation of anhydrite.A linear relationship between the pressure and temperature for the precipitation of anhydrite is established as P(GPa) =0.0068T - 0.7126 (250℃≤T≤320℃).Anhydrite remained stable during rapid cooling of the sample chamber,showing that the gypsum-anhydrite transition involving both dissolution and precipitation processes is irreversible at high pressure and high temperature.

关键词： saturated Transition Observation

HMFI分子筛Bronsted酸性位点与碱性分子的作用机制

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原子与分子物理学报 2025年第4期42卷 1-7页

作者：郑健秦康秦玉才宋丽娟中石化石油化工科学研究院有限公司北京100083 辽宁石油化工大学辽宁省石油化工催化科学与技术重点实验室抚顺113001

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_... 详细信息

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_(3)分子与HMFI分子筛的作用机制.研究表明分子筛Bronsted酸(简称B酸)强度与B酸数量没有强相关性,在考虑B酸位数量的同时须考虑B酸位的分布.酸性位点数量和分布的差异均可以调控NH_(3)分子的吸附构象,并且可以通过调节HMFI分子筛孔道对分子施加相互作用的模式,解析分子的结构和电子性质,精准调控分子的进一步转化.此项工作可以为未来高效多孔材料有效物种活性位的构建提供新思路.

关键词：密度泛函理论 HMFI分子筛 Bronsted酸性质吸附性能

Electrochemical investigation on the hydrogen permeation behavior of 7075-T6 Al alloy and its influence on stress corrosion cracking

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International Journal of Minerals,Metallurgy and Materials 2015年第7期22卷 729-737页

作者： chuan-bo zheng Bing-hao Yan Ke Zhang Guo Yi School of Materials Science and Engineering Jiangsu University of Science and Technology Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of Oceanology Chinese Academy of Sciences China Petroleum Pipeline Bureau

The hydrogen permeation behavior and stress corrosion cracking （SCC） susceptibility of precharged 7075-T6 A1 alloy were inves- tigated in this paper. Devanthan-Stachurski （D-S） cell tests were used to measure the apparent hydrogen diffusivity and hydrogen permeation current density of specimens immersed in 3.5wt% NaCl solution. Electrochemical experiment results show that the SCC susceptibility is low during anodic polarization. Both corrosion pits and hydrogen-induced cracking are evident in scanning electron microscope images after the specimens have been charging for 24 h.

关键词： aluminum alloys hydrogen permeation hydrogen embrittlement stress corrosion cracking

Study on Enzymatic Hydrolysis of Gadus morrhua Skin Collagen and Molecular Weight Distribution of Hydrolysates

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Agricultural Sciences in China 2009年第6期8卷 723-729页

作者： HUO jian-xin ZHAO zheng Jinzhong University Jinzhong 030600 P.R. China College of Food Engineering ＆ Biotechnology Tianjin University of Science ＆ Technology Tianjin 300457 P.R.China

Process parameters on enzymatic hydrolysis and molecular weight （MW） distribution of collagen hydrolysates from Gadus morrhua skin were investigated. The optimal process parameters were obtained by the single-factor and orthogonal experiments. The molecular weight distribution of hydrolysates was determined using both Sephadex G25 partition and high speed liquid chromatography electricity spray mass spectrum （HPLC-ESI-MS）. Collagen hydrolysates were first gained by an alkaline protease ＂alcalase＂ for 3 h at temperature （50~C）, pH （10.0）, substrate concentration （75 g L-~）, and E/S （3%）. The molecular weight distribution of collagen hydrolysates ranged from 300 to 1 500 Da, and most of peptides were under 1 200 Da. Sephadex G25 partition and HPLC-ESI-MS should be successfully employed to determine the molecular weight distribution of collagen hydrolysates.

关键词： collagen hydrolysates Gadus morrhua molecular weight distribution alkaline protease

Redesign of a conformal boundary recovery algorithm for 3D Delaunay triangulation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 2031-2042页

作者： CHEN jian-jun zheng Yao Center for Engineering and Scientific Computation School of Computer Science Zhejiang University Hangzhou 310027 China

Boundary recovery is one of the main obstacles in applying the Delaunay criterion to mesh generation. A stan- dard resolution is to add Steiner points directly at the intersection positions between missing boundaries and triangulations. We redesign the algorithm with the aid of some new concepts, data structures and operations, which make its implementation routine. Furthermore, all possible intersection cases and their solutions are presented, some of which are seldom discussed in the litera- ture. Finally, numerical results are presented to evaluate the performance of the new algorithm.

关键词： Boundary recovery Delaunay triangulation Mesh generation Data structure

A　source　extent　analysis　of　the　Lancang　earthquake(M_s=7.6)of　1988

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 393-402页

作者： Si-Hua zheng jian Yang Center for Analysis and Prediction China Seismological Bureau Beijing China

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关键词： M_s M_s=7.6)of the earthquake extent Lancang analysis