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X-ray-activated long persistent phosphors featuring strong UVC afterglow emissions

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Light(Science & Applications) 2018年第1期7卷 222-232页

作者： yan-Min yang Zhi-Yong Li Jun-Ying Zhang Yue Lu Shao-Qiang Guo Qing Zhao Xin Wang Zi-Jun Yong Hong Li Ju-ping Ma Yoshihiro Kuroiwa Chikako Moriyoshi Li-Li Hu Li-yan Zhang Li-Rong Zheng Hong-Tao Sun College of Physics Science and Technology Hebei University071002 BaodingChina College of Chemistry Chemical Engineering and Materials ScienceSoochow University215123 JiangsuChina Department of Physics Beihang University100191 BeijingChina Department of Physical Science Hiroshima UniversityHigashihiroshimaHiroshima 739-8526Japan Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences201800 ShanghaiChina Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences100049 BeijingChina

Phosphors emitting visible and near-infrared persistent luminescence have been explored extensively owing to their unusual properties and commercial interest in their applications such as glow-in-the-dark paints,optical information storage,and in vivo ***,no persistent phosphor that features emissions in the ultraviolet C range(200–280 nm)has been known to exist so ***,we demonstrate a strategy for creating a new generation of persistent phosphor that exhibits strong ultraviolet C emission with an initial power density over 10 milliwatts per square meter and an afterglow of more than 2 *** characterizations coupled with first-principles calculations have revealed that structural defects associated with oxygen introduction-induced anion vacancies in fluoride elpasolite can function as electron traps,which capture and store a large number of electrons triggered by Xray ***,we show that the ultraviolet C afterglow intensity of the yielded phosphor is sufficiently strong for *** discovery of this ultraviolet C afterglow opens up new avenues for research on persistent phosphors,and it offers new perspectives on their applications in terms of sterilization,disinfection,drug release,cancer treatment,anti-counterfeiting,and beyond.

关键词： ultraviolet fluoride visible

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关于当前全球矿业资源市场的发展趋势思考

中国矿业 2016年第S2期25卷 17-19,27页

作者：谢艳中国地质大学(北京)地球科学与资源学院北京100083

2015年全球主要矿产品价格持续震荡下跌以来,2016年一季度主要资源价格呈现整体上扬态势。但仍受全球经济深度转型调整以及市场实际需求疲软等影响,国际市场上主要资源价格和资本金融市场仍然波动不定,不确定性因素更是有增无减,这使得... 详细信息

2015年全球主要矿产品价格持续震荡下跌以来,2016年一季度主要资源价格呈现整体上扬态势。但仍受全球经济深度转型调整以及市场实际需求疲软等影响,国际市场上主要资源价格和资本金融市场仍然波动不定,不确定性因素更是有增无减,这使得全球矿业市场复苏希望微弱,资源价格全面反弹的局面难以持久。中国经济正处于供给侧改革的关键时期,一季度国民经济运行中的确出现了些许亮点,但是传统产业产能过剩及其化解过剩产能进程的动力与时滞约束,使得矿业产业和传统制造业的调整发展仍然非常困难,矿业资源产业投资对GDP的增长贡献率持续减缓,机构及投资者对矿业产业的投资热情和获利信心继续减少,矿业资源产业发展形势依然严峻,重振雄风仍待时日。

关键词：矿产价格资源产业资源市场趋势思考

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数字式图书馆海量文献数据查询优化仿真

计算机仿真 2019年第6期36卷 426-429页

作者：谢燕宝鸡文理学院

探究有效的海量文献数据查询优化方法,能够提高数据查询的运行速度,加快响应时间,增强查全率,在使用过程中具有重要的现实意义。为了解决查询海量数据时存在响应时间较长、运行速度较慢、准确率较低等问题,提出基于改进遗传算法的数据... 详细信息

探究有效的海量文献数据查询优化方法,能够提高数据查询的运行速度,加快响应时间,增强查全率,在使用过程中具有重要的现实意义。为了解决查询海量数据时存在响应时间较长、运行速度较慢、准确率较低等问题,提出基于改进遗传算法的数据查询优化方法,利用稀疏表示哈希算法构建海量文献数据模型,获取抽象空间中文献和文本信息的特征表示,计算二者隐藏在语义空间的相关近似值,得到海量文献数据目标函数。运用梯度将目标函数转换成新的适应度函数,利用函数值变化机率优化适应度函数,将十进制实数编码加入遗传算法中,根据概率选取染色体具有最小函数值时,由该值获取最优查询结果。仿真结果证明,所提方法在保证较短的平均响应时间和平均查询速度的基础上,提高查询的平均准确率和查全率。

关键词：文献数据查询优化查询速度平均准确率查全率

Some Massively Parallel Algorithms from Nature

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 37-46页

作者： Li yan, Kang Li-shan, Chen Yu-ping, Liu Pu, Cao Hong-qing, Pan Zheng-jun The State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, Hubei, China Wuhan University The State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

We introduced the work on parallel problem solvers from physics and biology being developed by the research team at the State Key Laboratory of Software Engineering, Wuhan University. Results on parallel solvers include the following areas: Evolutionary algorithms based on imitating the evolution processes of nature for parallel problem solving, especially for parallel optimization and model-building; Asynchronous parallel algorithms based on domain decomposition which are inspired by physical analogies such as elastic relaxation process and annealing process, for scientific computations, especially for solving nonlinear mathematical physics problems. All these algorithms have the following common characteristics: inherent parallelism, self-adaptation and self-organization, because the basic ideas of these solvers are from imitating the natural evolutionary processes.

关键词： evolutionary computation parallel algorithm imitating nature domain decomposition knowledge discovery in databases

NLOS环境下基于信号检测的单次与二次散射路径识别

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信号处理 2020年第5期36卷 733-740页

作者：谢少杰邓平西南交通大学信息编码与传输重点实验室四川成都611700

针对NLOS(Non-Line-of-Sight)传播环境中单次与多次散射路径的识别问题,本文基于单次散射圆环模型建立了一种二次散射圆环模型,对该模型的统计特征进行了分析。同时,基于信号统计检测理论建立了一种单次与二次散射路径检测模型,然后根... 详细信息

针对NLOS(Non-Line-of-Sight)传播环境中单次与多次散射路径的识别问题,本文基于单次散射圆环模型建立了一种二次散射圆环模型,对该模型的统计特征进行了分析。同时,基于信号统计检测理论建立了一种单次与二次散射路径检测模型,然后根据是否已知先验概率两种情况,分别采用广义似然比和奈曼皮尔逊准则来检测识别两种散射路径。仿真结果表明:本文提出的检测识别方法在NLOS环境下能有效识别两种散射路径,相对于LPMD(Line of Possible Mobile Device)算法具有更高的识别率以及更小的虚警概率和漏警概率,且时间开销小,具有一定的应用价值。

关键词：二次散射散射模型 non-line-of-sight 信号检测路径识别

Investigation of Breaking Efficiency of N-Glycosidic Bond Between Sulfonamide and Honey

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Chemical Research in Chinese Universities 2012年第2期28卷 195-199页

作者： WANG yan-hua LI Li CHEN Chia-hung CHENG Shuenn-ren LEE Mu-sheng YU Pu-ping CHANG-CHIEN Guo-ping College of Biology and Enviornmental Engineering Zhejiang Shuren University Hangzhou 310015 P. R. China Super Micro Mass Research ＆ Technology Center Department of Business Administration Department of Mechanical Engineering Cheng Shiu University Kaohsiung 833 Taiwan P. R. China Environmental Protection Bureau Kaohsiung City Government Keelung 20143 Taiwan P. R. China

Sulfonamide residue in honey existed in a form bonded to sugar via the N-glycosidic *** would result in the possible underestimation of concentration of sulfonamide if it is not decomposed by chemical ***,in China's Mainland and Taiwan（***）,the regulation for sulfonamide residue analysis does not include hydrolysis and has been applied to a very broad range of samples,for example,egg,milk,meat,seafood as well as *** paper demonstrates the necessity of hydrolysis of it prior to extracting *** breaking efficiencies of N-glycosidic bond were investigated by 2 mol/L hydrochloric acid,pure methanol and 0.5 mol/L hydrochloric acid in methanol,*** was found that acid plays the key role in breaking the N-glycosidic bond,and it was also noticed that the dissolution of liberated sulfonamide in methanol could carry the reaction forward in favor of breaking the N-glycosidic bond.

关键词： Sulfonamide Honey Liquid chromatography-electrospray ionization tandem mass spectrometry(LC-ESIMS/MS) N-Glycosidic bond

Drug research and development opportunities in low-and middle-income countries:accelerating traditional medicine through systematic utilization and comprehensive synergy

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Infectious Diseases of Poverty 2022年第2期11卷 77-80页

作者： Guangqi Liu yan xie Yinuo Sun Kaixuan Zhang Jiyan Ma yangmu Huang Department of Global Health Peking University School of Public Health38 Xue Yuan RoadHaidian DistrictBeijing 100191China Institute for Global Health Peking UniversityBeijingChina

Background:Though the utilization of traditional medicine has been proposed for modern drug research and development(R&D),limited research has discussed its feasible *** this commentary,we summarized key factors for new drug R&D under limited resources by reviewing China’s discovery of artemisinin,and raised suggestions to utilize traditional medicines in low-and middle-income countries(LMICs).Main text:We suggested that systematic utilization of traditional medicine,outstanding synergy of research units at all levels and timely information-sharing mechanism should be achieved to establish a comprehensive and efficient R&D system,especially under low-resource *** the case of artemisinin discovery,Chinese scientists integrated documented traditional medicine experiences and modern approaches to develop drug candidates *** to limited R&D resources,China adopted a collaborative way,motivating nearly all domestic research units at different levels,to develop antimalarial ***,the excellent synergy among all units through efficient information-sharing mechanisms greatly avoided work repetition and accelerated the R&D ***:Traditional medicines inspires drug discoveries in LMICs,while a comprehensive and efficient R&D system could accelerate its R&D process and save *** discovery of artemisinin in China gave a reliable pattern to promote sustainable development of traditional medicines and a good example to realize R&D of traditional medicine under low-resource settings.

关键词： Traditional medicine Research and development Low-and middle-income countries

The correlation between rat retinal nerve fiber layer thickness around optic disc by using optical coherence tomography and histological measurements

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International Journal of Ophthalmology(English edition) 2013年第4期6卷 415-421页

作者： Ju-Fang Huang Hui-Min Yu Lei Shang Ruo-Fei Ma Ngobe Akume Cynthia yan-Qun Cao Jia Luo Le-ping Zeng Dan Chen Kun Xiong Department of Anatomy and Neurobiology Central South University School of Basic Medical Sciences Department of Ophthalmology Central South University Third Xiangya Hospital Central South University Xiangya School of Medicine Department of Anatomy Shaoyang Medical College

·AIM: To explore the correlation between the retinal nerve fiber layer (RNFL) thickness by using optical coherence tomography (OCT) and by histological measurements in normal adult rats and optic nerve transected rats. · METHODS: The RNFL thickness of 36 rats was scanned in a circle 3.46mm far from the optic disc by OCT. The two experimental groups were the normal group ( =20 rats) and the optic nerve transected group ( =16 rats). The latter group included 4 groups ( =4 /group) surviving for 1 day, 3, 5 and 7 days. Then the RNFL thickness of the same retina area was also measured by NF -200 immunohistochemical staining method. Linear regression was used to analyze the correlation between the data obtained from these two methods. ·RESULTS: The RNFL thickness of normal right eyes around optic disc by OCT was 72.35 ±5.71μm and that of the left eyes was 72.65 ±5.88μm ( =0.074). The RNFL thickness of the corresponding histological section by immunohistochemistry was 37.54 ±4.05μm (right eyes) and 37.38 ±4.23μm (left eyes) ( =0.059). There was a good correlation between the RNFL thickness measured by OCT and that measured by histology (R 2 =0.8131). After optic nerve transection, the trend of the RNFL thickness was thinner with the prolonged survival time. The correlation of the thickness detected by the above two methods was approximately (R 2 =0.8265). Value of the RNFL thickness in rats around optic disc measured by OCT was obviously higher than that measured by common histological measurement in normal adult rats and optic nerve transected rats. ·CONCLUSION: The RNFL thickness measured by OCT has a strong correlation with that measured by histological method. Through OCT scanning, we found that the thickness of RNFL gradually becomes thinner in a time-dependent manner.

关键词： retinal nerve fiber layer thickness optical coherence tomography optic nerve transection immunohistochemistry staining relevance analysis rat

Enhanced photocatalytic activity of TiO_2 nanoparticles using WS_2/g-C_3N_4 hybrid as co-catalyst

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Transactions of Nonferrous Metals Society of China 2017年第5期27卷 1117-1126页

作者： Li-li ZHENG Xin-yan XIAO yang LI Wei-ping ZHANG School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China

TiO2/WS2/g-C3N4composite photocatalysts were synthesized by a liquid-exfoliation-solvothermal *** this process,the WS2/g-C3N4nano-sheets were prepared by liquid-exfoliation method from the bulk WS2and C3N4in the alcohol system,and then the TiO2nanoparticles(NPs)grew on the WS2/g-C3N4nano-sheets by in-situ synthesized *** photocatalytic activity of the as-prepared samples was evaluated by photocatalytic degradation of methyl orange(MO).The results showed that the as-prepared samples exhibited higher photocatalytic activities as compared to the pure TiO2,g-C3N4and TiO2/*** enhanced photocatalytic activities of TiO2/WS2/g-C3N4photocatalysts could be attributed to the synergistic effect of heterostructure between TiO2NPs and WS2/g-C3N4nano-sheets,which could efficiently improve the separation of photogenerated electron/hole pairs and utilization efficiency of *** quenching tests of radicals indicated that?O2?had crucial effect on degradation of MO,which demonstrated that?O2?was the main active radical in photocatalytic reaction process.

关键词： g-C3N4 TiO2 WS2 photocatalysis liquid-exfoliation solvothermal method