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吉林林业科技 2024年第4期53卷 33-37页

作者：姚雪丁京仲孙天玺吉林省林业调查规划院吉林长春130022 吉林长白山森工集团吉林延边133000

本文介绍了白山地区自然保护地概况,针对其存在的主要历史问题与现实冲突,提出了整合优化预案,分析了整合优化成果,为推进白山地区自然保护地体系建设提供参考。

关键词：白山地区自然保护地整合优化

On Native Origin of the American Indians

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Open Journal of Applied Sciences 2016年第9期6卷 636-647页

作者： tianxi sun Environmental Protection Bureau Suzhou China.

There have been controversies over differing opinions in the source of the American Indians. In this paper, the writer criticized the so-called classical theory that the remote ancestors of the American Indians entered America from Asia through the Bering Straits 14,000 ~ 20,000 years ago, worn their “clothes” and carried kindling during the late Paleolithic, no matter how by “boat” across the Bering Sea or by foot through a “Bering Land Bridge” which might once link up Asia and North America during glacial period;and independently proposed a new hypothesis that American Indians might be originated from the Western Rift Valley of North America. On the basis of locus distribution of American ancient human’s remnants, the writer pointed out that American ancient humans might be first originated at Yukon Territory of Canada within the Western Rift Valley of North America (the Basin & Range Province), and then migrated south ward (Yukon Territory → Mojave Desert → Mexico → Peru → Chile). Moreover, American Indians would have long been a presence for 40,000 years, or even 100,000 ~ 200,000 years in the American continents. So far, the logical basis which American Indians came from Asia 14,000 ~ 20,000 years ago was crushed, and derived two inferences: 1) American Indians might be originated from the Western Rift Valley of North America;2) Only the Eskimo might be the mover eastward from Asia, because of their gene B.

关键词： American Indians Native Origin Genetics of Human Blood Rift Valley Controversy

A Radiative-Cooling Hierarchical Aligned Porous Poly(vinylidene fluoride)Film by Freeze-Thaw-Promoted Nonsolvent-Induced Phase Separation

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Chinese Journal of Polymer Science 2024年第7期42卷 976-983,I0009页

作者： Yiting Zhang Jiahui sun Yufeng Wang Yunchen Wu Chun Huang Chao Zhang tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of Education School of Chemical and Material EngineeringJiangnan UniversityWuxi214122China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China

Passive daytime radiative cooling(PDRC)is an innovative and sustainable cooling technology that holds immense potential for addressing the energy *** the numerous reports on radiative coolers,the design of a straightforward,efficient,and readily producible system remains a ***,we present the development of a hierarchical aligned porous poly(vinylidene fluoride)(HAP-PVDF)film through a freeze-thaw-promoted nonsolvent-induced phase separation *** film features oriented microporous arrays in conjunction with random nanopores,enabling efficient radiative cooling performance under direct sunlight *** incorporation of both micro-and nano-pores in the HAP-PVDF film results in a remarkable solar reflectance of 97%and a sufficiently high infrared thermal emissivity of 96%,facilitating sub-environmental cooling at 18.3℃ on sunny days and 13.1℃ on cloudy ***,the HAP-PVDF film also exhibits exceptional flexibility and *** calculations further confirm a radiative cooling power of 94.8 W·m^(-2)under a solar intensity of 1000W·m^(-2),demonstrating a performance comparable to the majority of reported radiative coolers.

关键词： Daytime radiative cooling Hierarchical porosity PVDF porous film Thermal insulation Nonsolvent-induced phase separation

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毛细管X射线透镜技术及其应用

光学学报 2022年第11期42卷 20-39页

作者：孙天希北京师范大学射线束技术教育部重点实验室核科学与技术学院北京100875 北京市科学技术研究院辐射技术研究所北京100875

毛细管X射线透镜的工作原理是X射线全反射,它可以被设计成不同的形状以获得满足不同需求的各类高功率密度增益光束,如准平行束、微焦斑、环形束等。毛细管X射线透镜可以调控来自各类X射线源的X射线,如实验室传统X射线光源、同步辐射光... 详细信息

毛细管X射线透镜的工作原理是X射线全反射,它可以被设计成不同的形状以获得满足不同需求的各类高功率密度增益光束,如准平行束、微焦斑、环形束等。毛细管X射线透镜可以调控来自各类X射线源的X射线,如实验室传统X射线光源、同步辐射光源、激光等离子X射线光源、自由电子X射线激光装置、星系中X射线源等。毛细管X射线透镜可以方便经济地助力X射线技术发展,所以它被广泛应用在X射线技术领域,对X射线科学与技术的发展起到了重要作用。主要综述了近几年毛细管X射线透镜的设计、制备和应用情况,并对毛细管X射线透镜技术的进一步发展提出了展望。

关键词： X射线光学毛细管X射线透镜单毛细管X射线透镜多毛细管X射线透镜毛细管X射线透镜技术

Probing dark matter particles from evaporating primordial black holes via electron scattering in the CDEX-10 experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 83-91页

作者： Zhenhua Zhang Litao Yang Qian Yue Kejun Kang Yuanjing Li Haipeng An Greeshma C. Jianping Chang Yunhua Chen Jianping Cheng Wenhan Dai Zhi Deng Changhao Fang Xinping Geng Hui Gong Qiuju Guo Tao Guo Xuyuan Guo Li He Shengming He Jinwei Hu Hanxiong Huang Tuchen Huang Lin Jiang S.Karmakar Haubin Li Hanyu Li Jianmin Li Jin Li Qianyun Li Renmingjie Li Xueqian Li Yulan Li Yifan Liang Bin Liao FongKay Lin ShinTed Lin Jiaxuan Liu Shukui Liu Yandong Liu Yu Liu Yuanyuan Liu Hao Ma Yucai Mao Qiyuan Nie Jinhua Ning Hui Pan Ningchun Qi Jie Ren Xichao Ruan Monoj Kumar Singh tianxi sun Changjian Tang Yang Tian Guangfu Wang Junzheng Wang Li Wang Qing Wang Yufeng Wang Yunxiang Wang Henry Tsz-King Wong Shiyong Wu Yucheng Wu Haoyang Xing Rui Xu Yin Xu Tao Xue Yulu Yan Nan Yi Chunxu Yu Haijun Yu Jianfeng Yue Ming Zeng Zhi Zeng Bingtao Zhang Fengshou Zhang Lei Zhang Zhenyu Zhang Jizhong Zhao Kangkang Zhao Minggang Zhao Jifang Zhou Zuying Zhou Jingjun Zhu CDEX Collaboration Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua UniversityBeijing 100084China Department of Physics Tsinghua UniversityBeijing 100084China Institute of Physics Academia SinicaTaipei 11529China NUCTECH Company Beijing 100084China YaLong River Hydropower Development Company Chengdu 610051China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China College of Physics Sichuan UniversityChengdu 610065China School of Physics Peking UniversityBeijing 100871China Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413China Sino-French Institute of Nuclear and Technology Sun Yet-sen UniversityZhuhai 519082China School of Physics Nankai UniversityTianjin 300071China Department of Physics Banaras Hindu UniversityVaranasi 221005India Department of Physics Beijing Normal UniversityBeijing 100875China 不详

Dark matter(DM)is a major constituent of the ***,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to *** is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target *** examined PBH masses range from 1×10^(15)to 7×10^(16)g under the current limits of PBH abundance *** 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×10^(-29)cm^(2)forχwith a mass■keV from our *** the higher radiation background but lower energy threshold(160 eV),CDEX-10 fills a part of the gap in the previous ***(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.

关键词： CDEX primordial black hole light dark matter particle dark matter-electron scattering high purity germanium detector

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Developing cold-resistant high-adhesive electronic substrate for WIMPs detectors at CDEX

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Chinese Physics B 2020年第4期29卷 72-76页

作者： Yuanyuan Liu Jianping Cheng Pan Pang Bin Liao Bin Wu Minju Ying Fengshou Zhang Lin Chen Shasha Lv Yandong Liu tianxi sun Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Beijing Radiation Center Beijing 100875China

Herein we report a prototypical electronic substrate specifically designed to serve the weakly interacting massive particles(WIMPs)detectors at the China Dark Matter Experiment(CDEX).Because the bulky high-purity germanium(HPGe)detectors operate under liquid-nitrogen temperatures and ultralow radiation backgrounds,the desired electronic substrates must maintain high adhesivity across different layers in such cold environment and be free from any radioactive *** conquer these challenges,for the first time,we employed polytetrafluoroethylene((C2F4)n)foil as the base substrate,in conjunction with ion implantation and deposition techniques using an independently developed device at Beijing Normal University for surface modification prior to *** remarkable peeling strengths of 0.88±0.06 N/mm for as-prepared sample and 0.75±0.05 N/mm for that after 2.5-days of soaking inside the liquid nitrogen were observed,while the regular standards commonly require 0.4 N/mm^0.6 N/mm for electronic substrates.

关键词： WIMPs detector CDEX surface modification electronic substrate

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利用背散射方法测量整体X光透镜的性能

核技术 2006年第5期29卷 339-343页

作者：孙天希刘志国汪燕丁训良射线束技术与材料改性教育部重点实验室北京师范大学低能核物理研究所北京市辐射中心北京100875

为了避免探测系统的死时间问题,采用有机玻璃刀口作为散射体来降低探测系统死时间。通过分析来自有机玻璃散射体的背散射谱,测量了不同能量X射线在透镜会聚光束中的空间分布,为分析“光晕(halo)”现象提供了能谱依据,在此基础上,系统地... 详细信息

为了避免探测系统的死时间问题,采用有机玻璃刀口作为散射体来降低探测系统死时间。通过分析来自有机玻璃散射体的背散射谱,测量了不同能量X射线在透镜会聚光束中的空间分布,为分析“光晕(halo)”现象提供了能谱依据,在此基础上,系统地分析了“halo”现象。在大能量范围内,分别利用轴向扫描法和刀口扫描法测量了透镜出口焦距、发散度及焦斑大小与能量的关系。利用背散射方法测量透镜焦斑直径时的相对误差在3%以内;利用轴向扫描法确定透镜出口焦距时的绝对误差在–120—120μm之间。

关键词：整体X光透镜性能测量有机玻璃刀口背散射

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锥形单毛细管高能X射线微焦斑透镜模拟表征

光学学报 2022年第11期42卷 234-240页

作者：李惠泉邵尚坤孙学鹏袁天语华陆孙天希北京师范大学核科学与技术学院射线束技术教育部重点实验室北京100875 北京市科学技术研究院辐射技术研究所北京100875

高能X射线微焦斑在高能微束X射线分析技术中具有重要应用。为了获得高能X射线微焦斑透镜,理论设计了基于锥形单毛细管的高能X射线微焦斑透镜,该类锥形毛细管透镜可以把能量为100 keV的X射线会聚成微焦斑,焦斑直径和功率密度增益分别在... 详细信息

高能X射线微焦斑在高能微束X射线分析技术中具有重要应用。为了获得高能X射线微焦斑透镜,理论设计了基于锥形单毛细管的高能X射线微焦斑透镜,该类锥形毛细管透镜可以把能量为100 keV的X射线会聚成微焦斑,焦斑直径和功率密度增益分别在微米和几十量级,对应的焦距为5毫米左右;并且理论模拟了该类锥形毛细管透镜采用玻璃反射面和金属(纯金)反射面后的特性,在透镜焦斑处,采用纯金金属反射面的锥形毛细管透镜的光通量为采用普通硅酸盐玻璃反射面的锥形毛细管透镜的14.8倍。模拟结果对锥形单毛细管X射线透镜的研制和应用具有指导意义。

关键词： X射线光学锥形单毛细管X射线透镜高能X射线微焦斑镀膜

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检查防渗帷幕成效的新方法

江苏地质 1992年第2期16卷 106-109页

作者：孙天锡苏州市环境保护局苏州215002

教科书和工程规范皆以灌后ω值是否达到相对抗水层指标,作为决定水电站大坝基础中防渗帷幕的成败坏准。安徽省泾县纪村水电站因坝基渗漏曾两次设置丙凝帷幕,两次灌后ω值均远小于相对抗水层指标,但两次建幕都失败了。这说明灌后ω值检... 详细信息

教科书和工程规范皆以灌后ω值是否达到相对抗水层指标,作为决定水电站大坝基础中防渗帷幕的成败坏准。安徽省泾县纪村水电站因坝基渗漏曾两次设置丙凝帷幕,两次灌后ω值均远小于相对抗水层指标,但两次建幕都失败了。这说明灌后ω值检查法存在着局限性.

关键词：防渗帷幕水电站基础工程地质

Divergent responses of runoff to climate change in the upper basins of the Third Pole dominated by westerlies and monsoon

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Science China Earth Sciences 2024年第8期67卷 2592-2614页

作者： Qikai sun Fengge SU He sun State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China

The diverse climates,distribution of snow and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the Third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the westerlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in westerlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHT),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow(UYE),Lancang(ULC),Nujiang(UNJ),and Yarlung Zangbo(UYZ))of the Third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results showed that:(1)The annual runoff in the majority of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI showed a significant increasing trend from1961 to *** annual runoff in the upper basins of the Third Pole changed abruptly from decreasing to increasing between the 1980s and 2000s,with the exception of the UYE.(2)The runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the westerlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHT),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to warm season temperature changes in the most westerlies-dominated upper basins has decreased,while the response of runoff to precipitation changes has intensified.(3)The stud

关键词： Upper basins of the Third Pole Climate change Westerlies and monsoon Runoff variations Large-scale circulation factors

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