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Chinese Physics B 2024年第4期33卷 129-134页

作者：张雅芃姚嘉文刘正东马作霖仲佳勇 Department of Astronomy Beijing Normal UniversityBeijing 100875China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical phenomena.We use the Martin-Puplett interferometer(MPI)polarimeter to probe the peripheral magnetic fields generated in the common magnetic reconnection configuration,two separated coplanar plane targets,in laser-target interaction.We introduce a new method that can obtain polarization information from the interference pattern instead of the sinusoidal function fitting of the intensity.A bidirectional magnetic field is observed from the side view,which is consistent with the magneto-hydro-dynamical(MHD)simulation results of self-generated magnetic field reconnection.We find that the cancellation of reverse magnetic fields after averaging and integration along the observing direction could reduce the magnetic field strength by one to two orders of magnitude.It indicates that imaging resolution can significantly affect the accuracy of measured magnetic field strength.

关键词： laser-plasma experiment polarimeter self-generated magnetic field magnetic reconnection

Characteristics of combustion zone and evolution of mineral phases along bed height in ore sintering

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1087-1095页

作者： yao-zu Wang Jian-liang zhang Zheng-jian Liu ya-peng zhang Dong-hui Liu Yi-ran Liu School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Quantitative parameters of bed combustion, including the thickness of the combustion zone(TCZ), the maximum temperature of the combustion zone(MTCZ), and the bed shrinkage, were characterized through a series of sinter pot tests in transparent quartz pots. The results showed that TCZ first ascended and then descended as the sintering process proceeded. The sintering process was divided into four stages according to the variation rate of the TCZ. A "relative-coordinate" method was developed to obtain the actual reaction temperature of sinter along the height direction. With increasing the sintering temperature, the reactants transformed and entered into liquid phases. The mineral composition and microstructure of the sinter were characterized through X-ray diffraction and scanning electron microscopy–energy-dispersive X-ray spectroscopy. Liquid phases with greater Fe and Al contents were more likely to form acicular-like silico-ferrite of calcium and aluminum after crystallization because of the outward spread of Al, which led to a better fluidity of the liquid. An evolution mechanism of "solid-state reaction—liquid phases formation—crystallization" of the mineral phases is proposed.

关键词： flame front mineral phases sintering evolution mechanism transparent quartz pots

Preliminary analysis of fuel cycle performance for a small modular heavy water-moderated thorium molten salt reactor

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Nuclear Science and Techniques 2020年第11期31卷 23-35页

作者： ya-peng zhang Yu-Wen Ma Jian-Hui Wu Jin-Gen Chen Xiang-Zhou Cai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China CAS Innovative Academies in TMSR Energy System Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Heavy water-moderated molten salt reactors(HWMSRs)are novel molten salt reactors that adopt heavy water rather than graphite as the moderator while employing liquid fuel.Owing to the high moderating ratio of the heavy water moderator and the utilization of liquid fuel,HWMSRs can achieve a high neutron economy.In this study,a large-scale small modular HWMSR with a thermal power of 500 MWth was proposed and studied.The criticality of the core was evaluated using an in-house critical search calculation code(CSCC),which was developed based on Standardized Computer Analyses for Licensing Evaluation,version 6.1.The preliminary fuel cycle performances(initial conversion ratio(CR),initialfissile fuel loading mass,and temperature coefficient)were investigated by varying the lattice pitch(P)and the molten salt volume fraction(VF).The results demonstrate that the temperature coefficient can be negative over the range of investigated Ps and VFs for both 233U-Th and LEU-Th fuels.A core with a P of 20 cm and a VF of 20%is recommended for 233U-Th and LEU-Th fuels to achieve a high performance of initial CR and fuel loading.Regarding TRU-Th fuel,a core with a smaller P(~5 cm)and larger VF(~24%)is recommended to obtain a negative temperature coefficient.

关键词： Molten salt reactor Heavy water-moderated molten salt reactor(HWMSR) Th-U fuel cycle

The Potential Effects and Use of Chinese Herbal Medicine Pine Pollen(Pinus pollen):A Bibliometric Analysis of Pharmacological and Clinical Studies

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World Journal of Traditional Chinese Medicine 2020年第2期6卷 163-170页

作者： Shi-Bing Liang Ning Liang Fan-Long Bu Bao-Yong Lai ya-peng zhang Hui-Juan Cao Yu-Tong Fei Nicola Robinson Jian-Ping Liu Centre for Evidence-Based Chinese Medicine Beijing University of Chinese MedicineBeijing College of Basic Medical Sciences Shanxi University of Traditional Chinese MedicineTaiyuan Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing The Third Affiliated Hospital of Beijing University of Chinese Medicine BeijingChina School of Health and Social Care London South Bank UniversityLondonUK Institute of Integrated Traditional Chinese Medicine and Western Medicine Guangzhou Medical UniversityGuangzhouChina

The objectives of this study are to conduct a comprehensive literature search and bibliometric analysis to identify the breadth and volume of pharmacological and clinical studies on pine pollen(Pinus pollen)and to identify the potential effects and the use of pine pollen.Three Chinese electronic databases and two English electronic databases were searched for pharmacological and clinical studies on pine pollen.Data were extracted and analyzed and included publication year,authors,study type,pharmacological research topics or clinical diseases/conditions,usage and type of preparation,authors’conclusions,and adverse effects.Of 239 publications identified,180 were pharmacological studies,37 were clinical trials,and 22 were reviews.Numbers of publications increased particularly from 2004 onward.The top 10 most frequent topics in pharmacological studies were immune regulation,antisenility,antioxidation,liver protection,inhibiting prostate hyperplasia,inhibiting tumor cell proliferation,lowering blood glucose,lowering blood lipids,antifatigue,and improving intestinal function.The top 10 most frequent clinical diseases treated or where pine pollen was used as an adjuvant were bedsores,diaper dermatitis,hyperlipidemia,oral mucositis,eczema,hyperplasia of prostate,hypertension,prostatitis,type 2 diabetes mellitus,and radiodermatitis.Eight trials reported no adverse events associated with pine pollen,one reported mild gastrointestinal reactions,but symptoms disappeared without special management.There have been an increasing number of publications on pine pollen during the past 20 years.Pharmacological studies have shown many potential benefits,and clinical studies have indicated some positive effects when it is either used as a single herb or as an adjuvant to treat disease.Its use as a topical agent,especially for skin diseases,was notable.

关键词： Bibliometric analysis Chinese herbal medicine pine pollen Pinus pollen skin disease

Sex-biased adaptation shapes uniparental gene pools in Tibetans

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Science China(Life Sciences) 2024年第3期67卷 611-613页

作者： Min-Sheng peng ya-Ping zhang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming 650201China KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases Kunming Institute of ZoologyChinese Academy of SciencesKunming 650201China Kunming College of Life Science University of Chinese Academy of SciencesKunming 650204China State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan School of Life SciencesYunnan UniversityKunming 650091China

During the past two decades, a series of archaeological and genetic investigations substantially improve our perception of the hominin settlement of the Tibetan Plateau(zhang et al., 2022). In addition to the identifi... 详细信息

关键词： Tibetan Plateau altitude

An algorithm to resolve γ-rays from charged cosmic rays with DAMPE

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Research in Astronomy and Astrophysics 2018年第3期18卷 25-36页

作者： Zun-Lei Xu Kai-Kai Duan Zhao-Qiang Shen Shi-Jun Lei Tie-Kuang Dong Fabio Gargano Simone Garrappa Dong-ya Guo Wei Jiang Xiang Li Yun-Feng Liang Mario Nicola Mazziotta Maria Fernanda Munoz Salinas Meng Su Valerio Vagelli Qiang Yuan Chuan Yue Jing-Jing Zang ya-peng zhang Yun-Long zhang Stephan Zimmer Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China University of Chinese Academy of Sciences Beijing 100049 China Istituto Nazionale di Fisica Nucleare Sezione di Bari I-70125 Bari Italy Istituto Nazionale di Fisica Nucleare Sezione di Perugia I-06123 Perugia Italy Dipartimento di Fisica e Geologia Universita degli Studi di Perugia I-06123 Perugia Italy Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Nuclear and Particle Physics University of Geneva CH- 1211 Switzerland School of Astronomy and Space Science University of Science and Technology of China Hefei 230026 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of China Hefei 230026 China

The DArk Matter Particle Explorer（DAMPE）,also known as Wukong in China,which was launched on 2015 December 17,is a new high energy cosmic ray and γ-ray satellite-borne observatory.One of the main scientific goals of DAMPE is to observe Ge V-Te V high energy γ-rays with accurate energy,angular and time resolution,to indirectly search for dark matter particles and for the study of high energy astrophysics. Due to the comparatively higher fluxes of charged cosmic rays with respect to γ-rays,it is challenging to identify γ-rays with sufficiently high efficiency,minimizing the amount of charged cosmic ray contamination. In this work we present a method to identify γ-rays in DAMPE data based on Monte Carlo simulations,using the powerful electromagnetic/hadronic shower discrimination provided by the calorimeter and the veto detection of charged particles provided by the plastic scintillation detector. Monte Carlo simulations show that after this selection the number of electrons and protons that contaminate the selected γ-ray events at～10 Ge V amounts to less than 1% of the selected sample.Finally,we use flight data to verify the effectiveness of the method by highlighting known γ-ray sources in the sky and by reconstructing preliminary light curves of the Geminga pulsar.

关键词： gamma rays general - instrumentation detectors - methods data analysis

Implications on the origin of cosmic rays in light of 10 TV spectral softenings

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Frontiers of physics 2020年第2期15卷 101-109,F0004页

作者： Cliuan Yue peng-Xiong Ma Qiang Yuan Yi-Zhong Fan Zhan-Fang Chen Ming-yang Cui Hao-Ting Dai Tie-Kuang Dong Xiaoyuan Huang Wei Jiang Shi-Jun Lei Xiang Li Cheng-Ming Liu Hao Liu yang Liu Chuan-Ning Luo Xu Pan Wen-Xi peng Rui Qiao Yi-Feng Wei Li-Bo Wu Zhi-Hui Xu Zun-Lei Xu Guan-Wen Yuan Jing-Jing Zang ya-peng zhang Yong-Jie zhang Yun-Long zhang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Center for High Energy Physics Peking UniversityBeijing 100871China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Institute of Modem Physics Chinese Academy of SciencesLanzhou 730000China

Precise measurements of the energy spectra of cosmic rays(CRs)show various kinds of features deviating from single power-laws,which give very interesting and important implications on their origin and propagation.Previous measurements from a few balloon and space experiments indicate the existence of spectral softenings around 10 TV for protons(and probably also for Helium nuclei).Very recently,the DArk Matter Particle Explorer(DAMPE)measurement about the proton spectrum clearly reveals such a softening with a high significance.Here we study the implications of these new measurements,as well as the groundbased indirect measurements,on the origin of CRs.We find that a single component of CRs fails to fit the spectral softening and the air shower experiment data simultaneously.In the framework of multiple components,we discuss two possible scenarios,the multiple source population scenario and the background plus nearby source scenario.Both scenarios give reasonable fits to the wide-band data from TeV to 100 PeV energies.Considering the anisotropy observations,the nearby source model is favored.

关键词： cosmic rays

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research(International) 2024年第3期31卷 729-737页

作者： ya-zhou He ya-qing Hou peng Shen Hao zhang Dong Zhou Hang Su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and properties.Functionally graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co elements.The effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were studied.The as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of elements.The mechanical properties and magnetic properties of the compositionally graded sample show a gradient variation.With the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample decreases.The optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder metallurgy.LPBF in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

Automatic detection of small bowel lesions with different bleeding risks based on deep learning models

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World Journal of Gastroenterology 2024年第2期30卷 170-183页

作者： Rui-ya zhang peng-peng Qiang Ling-Jun Cai Tao Li yan Qin Yu zhang Yi-Qing Zhao Jun-Ping Wang Department of Gastroenterology The Fifth Clinical Medical College of Shanxi Medical UniversityTaiyuan 030012Shanxi ProvinceChina School of Computer and Information Technology Shanxi UniversityTaiyuan 030006Shanxi ProvinceChina School of Life Sciences and Technology Mudanjiang Normal UniversityMudanjiang 157011Heilongjiang ProvinceChina

BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some unresolved challenges.AIM To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups.METHODS The proposed model represents a two-stage method that combined image classification with object detection.First,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid images.Then,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was marked.We constructed training and testing sets and compared model-assisted reading with physician reading.RESULTS The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single module.The sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’diagnoses.The image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.

关键词： Artificial intelligence Deep learning Capsule endoscopy Image classification Object detection Bleeding risk

Pollution source identification methods and remediation technologies of groundwater: A review

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China Geology 2024年第1期7卷 125-137页

作者： ya-ci Liu Yu-hong Fei ya-song Li Xi-lin Bao peng-wei zhang Fujian Provincial Key Laboratory of Water Cycling and Eco-Geological Processes Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesXiamen 361000China Key Laboratory of Water and Soil Resources Conservation and Restoration in the Middle and Lower Reaches of Yellow River Basin MNRZhengzhou 450016China

Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies.

关键词： Groundwater pollution Identification of pollution sources Geophysical exploration identification Geochemistry identification Isotopic tracing Numerical modeling Remediation technology Hydrogeological conditions Hydrogeological survey engineering