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气相色谱与高分辨质谱联用(GC-HRMS)检测人尿中低浓度的甾体兴奋剂 被引量:2
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作者 王杰 蔡耘 +5 位作者 桑志红 钱小红 杨松成 吴牟天 刘欣 徐友宣 《质谱学报》 EI CAS CSCD 1999年第2期17-21,共5页
〕本文应用了气相色谱——高分辨质谱(GC- HRMS)联用及多离子检测技术(MID),建立了人尿中低浓度康力龙、克伦特罗、5β-4 羟基甲睾三种甾体激素类药物在低浓度时的检测方法,应用此方法成功地检测了奥林匹克运动委员... 〕本文应用了气相色谱——高分辨质谱(GC- HRMS)联用及多离子检测技术(MID),建立了人尿中低浓度康力龙、克伦特罗、5β-4 羟基甲睾三种甾体激素类药物在低浓度时的检测方法,应用此方法成功地检测了奥林匹克运动委员会(TOC)考核尿样中低浓度(2ng/m l)的康力龙、克伦特罗、5β- 展开更多
关键词 康力龙 克伦特罗 甾体兴奋剂检测 尿样 羟基甲睾
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Doping effects of manganese on the catalytic performance and structure of NiMgO catalysts for controllabe synthesis of multi-walled carbon nanotubes 被引量:4
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作者 Maofei Ran Wei Chu +3 位作者 Yan Liu Dong Liu Chang Zhang Jiae Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第6期781-788,共8页
Doping effects of manganese (Mn) on catalytic performance and structure evolution of NiMgO catalysts for synthesis of multi-walled carbon nanotubes (MWCNTs) from methane were investigated for the first time. Addit... Doping effects of manganese (Mn) on catalytic performance and structure evolution of NiMgO catalysts for synthesis of multi-walled carbon nanotubes (MWCNTs) from methane were investigated for the first time. Addition of Mn in NiMgO catalyst can greatly improve the MWCNTs yield. Mno.2NiMgO catalyst among the tested ones gives the highest MWCNTs yield as 2244%, which is two times higher than that of the catalyst without Mn. The structure evolution, reduction behaviors and surface chemical properties of MnNiMgO catalysts with various Mn contents were studied in detail. It was found that the stable solid solution of NiMgO2 formed in NiMgO catalyst was disturbed by the addition of Mn. Instead, another solid solution of MnMg608 is formed. More amount of Ni can be reduced and dispersed on the catalyst surface to be acted as active sites. Importantly, the changes of Ni content on the surface are correlated with the Ni particle size and the outer diameter of MWCNTs, suggesting the controllable synthesis of MWCNTs over MnNiMgO catalysts. 展开更多
关键词 doping effect MANGANESE NiMgO catalyst controllable synthesis carbon nanotubes
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Foodborne doping and supervision in sports 被引量:1
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作者 Wei Chen Xiaoyu Cheng +1 位作者 Yingnan Ma Ning Chen 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期1925-1936,共12页
Cases of foodborne doping are frequently reported in sports events and can cause severe consequences for athletes.The foodborne doping can be divided into natural endogenous and artifi cially added foods according to ... Cases of foodborne doping are frequently reported in sports events and can cause severe consequences for athletes.The foodborne doping can be divided into natural endogenous and artifi cially added foods according to the sources,including anabolic agents,stimulants,diuretics,β-blockers,β2 agonists and others.In order to control foodborne doping,chromatographic technique,immunoassay,nuclear magnetic resonance,biosensor technology,pyrolytic spectroscopy,comprehensive analysis and electrochemical analysis have usually used as analytical and inspection strategies.Meanwhile,the legislation of anti-doping,the improvement of testing standard and technology,and the prevention and control of food safety,as well as the improvement of risk perception of athletes are highly necessary for achieving the effective risk control and supervision of foodborne doping,which will be benefi cial for athletes,doctors and administrators to avoid the risks of foodborne doping test and reduce foodborne doping risks for the health of athletes. 展开更多
关键词 Foodborne doping doping control ATHLETES ANTI-doping SUPERVISION
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Controlling magnetism in 2D CrI3 by electrostatic doping
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作者 Zheng Han 《Journal of Semiconductors》 EI CAS CSCD 2019年第8期2-2,共1页
Spin ordering in a semiconductor has attracted much attention in the community of condensed matter physics. By combining ferromagnetism and the semiconducting nature, systems such as Mn-doped PbSnTe or InAs were found... Spin ordering in a semiconductor has attracted much attention in the community of condensed matter physics. By combining ferromagnetism and the semiconducting nature, systems such as Mn-doped PbSnTe or InAs were found to exhibit tunable magnetic properties responsive to an externally applied electric field. It thus holds great promises for developing novel spintronics with the tuning-knobs such as gate voltage. Conventionally, those systems are often studied in bulk forms and commonly referred to diluted magnetic semiconductor (DMS). 展开更多
关键词 controlling MAGNETISM 2D CrI3 ELECTROSTATIC doping DILUTED magnetic SEMICONDUCTOR (DMS)
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Doping Control Analysis of 16 Non-Steroidal Anti-Inflammatory Drugs in Equine Plasma Using Liquid Chromatography-Tandem Mass Spectrometry
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作者 Youwen You Cornelius E. Uboh +1 位作者 Fuyu Guan Lawrence R. Soma 《American Journal of Analytical Chemistry》 2014年第17期1184-1199,共16页
Non-steroidal anti-inflammatory drugs (NSAIDs) are classified as Class 4 agents by the Association of Racing Commissioners International and are banned in racehorses during competition in Pennsylvania (PA). To control... Non-steroidal anti-inflammatory drugs (NSAIDs) are classified as Class 4 agents by the Association of Racing Commissioners International and are banned in racehorses during competition in Pennsylvania (PA). To control the abuse of these agents in racehorses competing in PA, a forensic method for screening and confirmation of the presence of these agents is needed. Equine plasma (0.5 mL) was acidified with 75 μL 1M H3PO4 to increase recovery of the analytes by liquid-liquid extraction using methyl tert-butyl ether (MTBE). Extracted analytes were separated by reversed-phase liquid chromatography using a C8 column under gradient condition. All 16 analytes were detected, quantified and confirmed using a triple quadrupole tandem mass spectrometry with selected reaction monitoring (SRM) in both negative and positive electrospray ionization modes. The limit of detection, quantification and confirmation of the analytes were 1.0 - 5.0 ng/mL, 1.0 - 5.0 ng/mL and 1.0 - 20 ng/mL, respectively. The linear dynamic range of quantification was 5.0 - 200 ng/mL. The method is routinely used in anti-doping analysis to control the abuse of NSAIDs in racehorses competing in PA. 展开更多
关键词 EQUINE PLASMA doping control NON-STEROIDAL ANTI-INFLAMMATORY DRUGS Liquid
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Controlled moderative sulfidation-fabricated hierarchical heterogeneous nickel sulfides-based electrocatalyst with tripartite Mo doping for efficient oxygen evolution
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作者 Xing Yu Qingyun Lv +6 位作者 Lulu She Long Hou Yves Fautrelle Zhongming Ren Guanghui Cao Xionggang Lu Xi Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第5期780-788,共9页
An electrocatalyst with heterogeneous nanostructure, especially the hierarchical one, generally shows a more competitive activity than that of its single-component counterparts for oxygen evolution reaction(OER), due ... An electrocatalyst with heterogeneous nanostructure, especially the hierarchical one, generally shows a more competitive activity than that of its single-component counterparts for oxygen evolution reaction(OER), due to the synergistically enhanced kinetics on enriched active sites and reconfigured electronic band structure. Here this work introduces hierarchical heterostructures into a NiMo@NiS/MoS_(2)@Ni_(2)S_(2)/MoO_(x)(NiMoS) composite by one-pot controlled moderative sulfidation. The optimal solvent composition and addition of NaOH enable NiMoS to own loose and porous structures, smaller nanoparticle sizes, optimal phase composition and chemical states of elements, improving the OER activity of NiMoS. To achieve current densities of 50 and 100 mA cm^(-1), small overpotentials of 275 and 306 mV are required respectively, together with a minor Tafel slope of 58 mV dec^(-1), which outperforms most reported sulfide catalysts and IrO_(2). The synergistic effects in the hierarchical heterostructures expose more active sites,adjust the electronic band structure, and enable the fast charge transfer kinetics, which construct an optimized local coordination environment for high OER electrocatalytic activity. Furthermore, the hierarchical heterostructures suppress the distinct lowering of electrical conductivity and collapse of pristine structures resulted from the metal oxidation and synchronous S leaching during OER, yielding competitive catalytic stability. 展开更多
关键词 OER electrocatalysts controlled moderative sulfidation Hierarchical heterostructures Nickel sulfides Tripartite Mo doping
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Photo-Doped Active Electrically Controlled Terahertz Modulator
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作者 Bo Zhang Liang Zhong +1 位作者 Ting He Jing-Ling Shen 《Journal of Electronic Science and Technology》 CAS CSCD 2015年第2期113-116,共4页
We demonstrate an electric-controlled terahertz(THz) modulator which can be used to realize amplitude modulation of terahertz waves with slight photo-doping. The THz pulse transmission was efficiently modulated by e... We demonstrate an electric-controlled terahertz(THz) modulator which can be used to realize amplitude modulation of terahertz waves with slight photo-doping. The THz pulse transmission was efficiently modulated by electrically controlling the monolayer silicon-based device. The modulation depth reached 100% almost when the applied voltage was 7V at an external laser intensity of 0.6W/cm2. The saturation voltage reduced with the increase of the photo-excited intensity. In a THz continuous wave(CW)system, a significant fall in both THz transmission and reflection was also observed with the increase of applied voltage. This reduction in the THz transmission and reflection was induced by the absorption for electron injection. The results show that a high-efficiency and high modulation depth broadband electric-controlled terahertz modulator in a pure Si structure has been realized. 展开更多
关键词 modulator terahertz saturation electrically doping modulated controlled excited monolayer tunable
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Fairness in Olympic sports:How can we control the increasing complexity of doping use in high performance sports?
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作者 Walter Herzog 《Journal of Sport and Health Science》 SCIE 2017年第1期47-,共1页
With the Rio Olympics just a few months past,we remember the excitement,the incredible performances,and the controversies.As happens so often,the Olympic Games focus attention not only on athletic achievements but als... With the Rio Olympics just a few months past,we remember the excitement,the incredible performances,and the controversies.As happens so often,the Olympic Games focus attention not only on athletic achievements but also on how athletes may reach ever-increasing levels of performance.Doping,medical 展开更多
关键词 Fairness in Olympic sports How can we control the increasing complexity of doping use in high performance sports high
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Analysis of Beta-blockers in Doping Control
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作者 Hong Jin DUAN Hong Ju FANG Yan Qing XU Tong Hui ZHOU Hua CHI Yun WU You Xuan XU Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing 100050,China 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期231-234,共4页
A retiabte and sensitive method is developed for the detection of β-blockers which are excreted in free or conjugated forms in human urine.9 β-blockers were derivatized by MSTFA and MBTFA and subjected to GC/MSB ana... A retiabte and sensitive method is developed for the detection of β-blockers which are excreted in free or conjugated forms in human urine.9 β-blockers were derivatized by MSTFA and MBTFA and subjected to GC/MSB analysis.Both chromato- grams and mass spectrometric data were obtained from full scanning mode.This method is suitable for routine screening and confirmation of β-blockers in doping control. 展开更多
关键词 Analysis of Beta-blockers in doping control
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磷酸锰铁锂正极材料改性研究进展 被引量:3
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作者 文志朋 潘凯 +5 位作者 韦毅 郭佳文 覃善丽 蒋雯 吴炼 廖欢 《储能科学与技术》 CAS CSCD 北大核心 2024年第3期770-787,共18页
正极材料是决定锂离子电池性能的关键材料之一,直接影响电池的能量密度、循环寿命、倍率性能及安全性能。橄榄石型LiMnFePO4具有能量密度高、成本低、环境友好、安全稳定等优点,被认为是一种很有前途的锂离子电池正极材料。然而,LiMnFe... 正极材料是决定锂离子电池性能的关键材料之一,直接影响电池的能量密度、循环寿命、倍率性能及安全性能。橄榄石型LiMnFePO4具有能量密度高、成本低、环境友好、安全稳定等优点,被认为是一种很有前途的锂离子电池正极材料。然而,LiMnFePO4具有橄榄石结构磷酸盐基化合物电子电导率低、Li+一维扩散速率慢等固有缺陷,严重阻碍了其在高性能锂离子电池中的大规模应用。如何提升LiMnFePO4的导电子/离子性能,是当前需要解决的关键问题。本文全面综述了LiMnFePO4正极材料的结构特征、合成方法及其导电性能提升的研究进展,着重介绍了表面包覆、形貌控制和离子掺杂等方法对提升LiMnFePO4正极材料导电性能的效果及其作用机理,虽然上述三类改性方法均可一定程度地优化材料颗粒间电子/离子传输路径,实现LiMnFePO4正极材料导电性能的提升。但是单独采用这些方法依然难以从根本上解决LiMnFePO4导电性差的问题。为进一步提升LiMnFePO4正极材料的综合性能,本文在总结当前研究进展的基础上,对LiMnFePO4未来的研究思路和发展方向进行了展望。提出了通过杂原子掺杂优质碳材料包覆、短b轴形貌控制以及离子掺杂等方法联合改性的策略。该策略有望进一步提升LiMnFePO4正极材料的导电性能,获得高容量、高倍率、高稳定性的LiMnFePO4正极材料。 展开更多
关键词 磷酸锰铁锂 导电性能 表面包覆 形貌控制 离子掺杂
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我国兴奋剂风险防控最佳实施模式的构建及应用
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作者 刘宪哲 孙桂芳 +3 位作者 刘雪琪 李树宇 刘玉 张霈 《山东体育科技》 2024年第1期43-48,共6页
该研究运用文献资料法、专家访谈法、特尔菲法等,对当下我国兴奋剂风险防控体系进行再审视,并结合中国反兴奋剂管理的具体实践和经验,最终构建出我国新时代兴奋剂风险防控的最佳实施模式,主要由体系建设、制度建设、教育预防、检查、结... 该研究运用文献资料法、专家访谈法、特尔菲法等,对当下我国兴奋剂风险防控体系进行再审视,并结合中国反兴奋剂管理的具体实践和经验,最终构建出我国新时代兴奋剂风险防控的最佳实施模式,主要由体系建设、制度建设、教育预防、检查、结果管理、三品管理、综合性赛事、合作交流与创新评估自查等9个一级指标、33个二级指标和17个三级指标构成,并将最佳实施模式在实践中进行应用。新架构的我国反兴奋剂风险防控体系的最佳实施模式是不断完善运动项目的反兴奋剂治理体系的重要体现,是全面落实“零出现”的重要抓手,同时也为国家队和省市运动队反兴奋剂工作治理体系建设和治理能力提高提供主要的依据和参考。 展开更多
关键词 兴奋剂 风险防控体系 最佳实施模式 应用
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正极材料LiAl_(0.08)Mn_(1.92)O_(4)单晶颗粒形貌演变及电化学性能
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作者 朱琴 马姣 +6 位作者 钱志慧 罗宇旭 郭昱娇 向明武 刘晓芳 宁平 郭俊明 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第8期1549-1562,共14页
联合元素掺杂和形貌调控策略,采用固相燃烧法和不同焙烧温度处理合成LiAl_(0.08)Mn_(1.92)O_(4)正极材料。实验结果表明,Al掺杂和焙烧温度的变化未改变LiMn_(2)O_(4)的相结构,随着温度的升高,结晶性增强,颗粒尺寸增大,其中焙烧温度650... 联合元素掺杂和形貌调控策略,采用固相燃烧法和不同焙烧温度处理合成LiAl_(0.08)Mn_(1.92)O_(4)正极材料。实验结果表明,Al掺杂和焙烧温度的变化未改变LiMn_(2)O_(4)的相结构,随着温度的升高,结晶性增强,颗粒尺寸增大,其中焙烧温度650℃是形成截断八面体单晶颗粒形貌的关键温度,750℃是颗粒突然变大的突变温度。650℃优化焙烧温度下焙烧的LiAl_(0.08)Mn_(1.92)O_(4)形成了较完整的包含(111)、(110)和(100)晶面的截断八面体单晶颗粒形貌,表现出优良的电化学和动力学性能。在1C下其首次放电比容量为112.0 mAh·g^(-1),循环500次后容量保持率为72.9%,在5C和10C倍率下,其首次放电比容量可达到107.1和100.4 mAh·g^(-1),经2000次长循环后,容量保持率为52.2%和53.5%。并且具有最小氧化还原峰电位差(ΔE_(p2),循环前后分别为0.109和0.114 V)、最小电荷转移电阻(R_(ct),循环前后分别106.49和125.49Ω)及较大的锂离子扩散系数(D_(Li^(+))=1.72×10^(-16)cm^(2)·s^(-1)),表现出较好的电化学可逆性和较快的锂离子扩散速率。Al掺杂和单晶截断八面体颗粒形貌既有效抑制了LiMn_(2)O_(4)的Jahn-Teller畸变,又降低了Mn溶解,提高了材料的倍率性能和长循环寿命。 展开更多
关键词 尖晶石LiMn_(2)O_(4) AL掺杂 固相燃烧法 焙烧温度 形貌调控 截断八面体
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人工智能赋能兴奋剂管制:价值意蕴、现实挑战与发展策略
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作者 徐伟康 《体育科学》 北大核心 2024年第1期50-58,F0003,共10页
反兴奋剂领域对技术的变革有着天然的敏感性,受益于人工智能技术的快速发展,兴奋剂管制渐趋迈向智能化。通过调研文献资料、运用逻辑分析等方法,探讨人工智能赋能兴奋剂管制的价值意蕴、现实挑战与发展策略。研究认为,基于人工智能的反... 反兴奋剂领域对技术的变革有着天然的敏感性,受益于人工智能技术的快速发展,兴奋剂管制渐趋迈向智能化。通过调研文献资料、运用逻辑分析等方法,探讨人工智能赋能兴奋剂管制的价值意蕴、现实挑战与发展策略。研究认为,基于人工智能的反兴奋剂情报整合和检查、样本检测和分析、智慧管理为兴奋剂管制带来情检一体、多维锁定、全链支撑的模式变革。但是,兴奋剂管制中人工智能的应用也面临着模型误差、意识无涉的技术性难题,权益侵害、责任模糊的合法性挑战,算法歧视、黑箱效应、技术僭越的伦理性风险。为更好地促进人工智能技术在兴奋剂管制中的应用,应当从数据质量控制、算法驱动变革、加强设计保护完善技术控制;从运动员权利保护的构建、数据和算法规制的形塑、监管和责任的设置优化法律体系;从技术辅助的定位、数字人权的导向、多方参与的治理增强伦理适配。 展开更多
关键词 人工智能 兴奋剂管制 数据分析 风险规制 权利保护
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冬季项目运动员的兴奋剂风险及防控策略研究
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作者 刘阳 赵昀光 +1 位作者 陈素峰 柴建中 《当代体育科技》 2024年第3期183-186,共4页
目的:分析我国冬季项目运动员的兴奋剂风险,提出防控兴奋剂风险的策略,以期为冬季项目运动员和教练员防范兴奋剂违规提供借鉴与参考。方法:运用文献资料法、逻辑分析法等研究方法进行全面分析。问题结论:冬季项目运动员的兴奋剂风险包... 目的:分析我国冬季项目运动员的兴奋剂风险,提出防控兴奋剂风险的策略,以期为冬季项目运动员和教练员防范兴奋剂违规提供借鉴与参考。方法:运用文献资料法、逻辑分析法等研究方法进行全面分析。问题结论:冬季项目运动员的兴奋剂风险包括食品药品营养品的兴奋剂风险、反兴奋剂教育的缺乏、冬季项目运动员的培养方式、冬季项目运动员的管理问题、冬季项目训练基层反兴奋剂基础薄弱等方面。对策:冬季项目运动员兴奋剂风险防控策略包括加强对食品药品营养品的管理,加强反兴奋剂教育,明确划分反兴奋剂责任,加强运动队的纪律和反兴奋剂管理,开展冬季项目兴奋剂检查工作等。 展开更多
关键词 冬季项目 运动员 兴奋剂风险 防控策略 反兴奋剂教育 兴奋剂检查
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电子竞技兴奋剂管制的必要证成、合理边界及困境克服
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作者 王桢 《湖北体育科技》 2024年第1期9-13,59,共6页
随着电子竞技赛事的繁荣发展,选手滥用兴奋剂的问题也日益凸显。运用文献资料、逻辑分析等研究方法,从电子竞技兴奋剂管制的必要性出发,探讨了电子竞技兴奋剂管制的合理边界及困境克服的内容。研究发现,鉴于电子竞技选手服用的精神型兴... 随着电子竞技赛事的繁荣发展,选手滥用兴奋剂的问题也日益凸显。运用文献资料、逻辑分析等研究方法,从电子竞技兴奋剂管制的必要性出发,探讨了电子竞技兴奋剂管制的合理边界及困境克服的内容。研究发现,鉴于电子竞技选手服用的精神型兴奋剂的严重危害性、电子竞技的本质和推广发展需求,但考虑到电子竞技的特殊性决定了它存在独特的管制边界,可以在禁用清单、行踪信息、药检技术等方面设立与传统体育项目不同的规定,以管制目的的实现有的放矢,维护电子竞技赛事的公平秩序。同时,还需采用疏导参赛者抵触情绪、规范药检程序、完善相关制度缺陷、适用前置性违规预防措施等多元化方法,为行业的繁荣发展保驾护航。 展开更多
关键词 电子竞技 兴奋剂 兴奋剂管制 非传统竞技体育
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妨害兴奋剂管理罪的刑法问题研究
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作者 闻志强 刘安妍 《医学与法学》 2024年第4期24-34,共11页
我国《刑法修正案(十一)》增设妨害兴奋剂管理罪,不仅符合涉兴奋剂行为入罪的国际趋势,也弥补了长期以来我国反兴奋剂法律规制体系的漏洞,有力保障了国家体育事业的发展,因而具有合理性与必要性。本罪所保护的法益为复合法益,即首先为... 我国《刑法修正案(十一)》增设妨害兴奋剂管理罪,不仅符合涉兴奋剂行为入罪的国际趋势,也弥补了长期以来我国反兴奋剂法律规制体系的漏洞,有力保障了国家体育事业的发展,因而具有合理性与必要性。本罪所保护的法益为复合法益,即首先为国家对兴奋剂的管理秩序和公平公正的体育竞争秩序,其次为运动员的身心健康。根据法条规定和行为性质,本罪的客观行为包括“诱使型”“帮助型”“支配型”三种类型,但不包括“运动员使用型”行为;其行为主体为一般主体,即仅为自然人而不包含单位;其行为对象限于国家登记注册并进行管理、能够参加国内国际重大体育竞赛的专业竞技运动员;其适用场域为全国性和国际性竞技体育竞赛。 展开更多
关键词 兴奋剂 妨害兴奋剂管理罪 法益 体育竞争秩序 体育竞赛
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多功能防腐蚀纳米平台:聚多巴胺包覆的铈掺杂中空介孔二氧化硅球
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作者 刘金辉 《当代化工研究》 CAS 2024年第8期178-181,共4页
pH诱导纳米容器骨架响应性降解和缓蚀剂释放可用于实现腐蚀的协同修复效果。本文通过水热法合成了聚多巴胺包覆的铈掺杂中空介孔二氧化硅纳米球(Ce-HMSN@PDA)。结果表明Ce-HMSN@PDA可作为装载缓蚀剂(MBT)的高效纳米载体,负载量达15%。MB... pH诱导纳米容器骨架响应性降解和缓蚀剂释放可用于实现腐蚀的协同修复效果。本文通过水热法合成了聚多巴胺包覆的铈掺杂中空介孔二氧化硅纳米球(Ce-HMSN@PDA)。结果表明Ce-HMSN@PDA可作为装载缓蚀剂(MBT)的高效纳米载体,负载量达15%。MBT在中性pH条件下被PDA层包裹,基本实现缓蚀剂的零释放。而在pH值降低时,Ce-HMSN骨架和PDA层发生响应性降解实现了对缓蚀剂的可控持续释放。这一功能将利于该新型纳米容器快速感受腐蚀引起的微环境pH变化从而自发释放缓释剂以抑制腐蚀。更重要的是,伴随着骨架降解释放的游离Ce^(3+)可以和释放的缓蚀剂共同作用以实现对基体的协同腐蚀防护。本研究的结果表明Ce-HMSN@PDA是一种用于高效腐蚀防护处理的多功能纳米平台。 展开更多
关键词 中空铈掺杂二氧化硅 多功能纳米容器 控制释放 协同腐蚀修复
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Zn-Al共掺杂和形貌调控制备LiMn_(2)O_(4)正极材料及其电化学性能
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作者 朱琴 马姣 +3 位作者 钱志慧 李萌 郭昱娇 郭俊明 《精细化工》 EI CAS CSCD 北大核心 2024年第6期1246-1253,1269,共9页
采用固相燃烧法在不同焙烧温度(600、650、700和750℃)下制备了LiZn_(0.05)Al_(0.03)Mn_(1.92)O_(4)正极材料,采用XRD、SEM、XPS对其进行了表征,通过循环伏安(CV)和电化学阻抗(EIS)测试了其电化学性能。结果表明,Zn-Al共掺杂和焙烧温度... 采用固相燃烧法在不同焙烧温度(600、650、700和750℃)下制备了LiZn_(0.05)Al_(0.03)Mn_(1.92)O_(4)正极材料,采用XRD、SEM、XPS对其进行了表征,通过循环伏安(CV)和电化学阻抗(EIS)测试了其电化学性能。结果表明,Zn-Al共掺杂和焙烧温度未改变LiMn_(2)O_(4)的晶体结构,正极材料的结晶性随焙烧温度(<750℃)的升高而增加,650℃及以上时形成了较多包含高暴露(111)晶面、小面积(110)、(100)晶面的截断八面体形貌晶粒,但750℃时正极材料发生部分分解。焙烧温度650℃的样品(LZAMO-650)表现出最佳的电化学性能,在5 C和10 C倍率下,初始放电比容量分别为101.3、99.9 mA·h/g,循环1000圈后容量保持率分别为81.5%、74.3%;LZAMO-650样品极化作用较小,有较好的循环可逆性,具有较低的电荷转移阻抗(R_(ct)=132.14Ω)和较大的锂离子扩散系数(DLi^(+)=3.65×10^(–16)cm^(2)/s)。Zn-Al共掺杂和形貌调控改性LiMn_(2)O_(4)正极材料有效抑制了Jahn-Teller效应,形成的截断八面体颗粒形貌降低了Mn的溶解,同时提供了更多的Li^(+)迁移三维通道,从而改善了材料的电化学性能。 展开更多
关键词 固相燃烧法 尖晶石LiMn_(2)O_(4) Zn-Al共掺 形貌调控 焙烧温度 JAHN-TELLER效应 Mn溶解 功能材料
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Controlled Synthesis and Application of α-Al_2O_3 for Lu_3Al_5O_(12): Ce^(3+) Green Spherical Phosphors 被引量:6
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作者 LI Zhao WANG Yongfeng CAO Jing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第5期1028-1031,共4页
Al2O3 powders with different morphologies,namely fibrous,sheet-like,and spherical,were prepared by the hydrothermal-thermolysis method.Subsequently,polycrystalline,transparent cerium doped lutetium aluminum garnet(Lu... Al2O3 powders with different morphologies,namely fibrous,sheet-like,and spherical,were prepared by the hydrothermal-thermolysis method.Subsequently,polycrystalline,transparent cerium doped lutetium aluminum garnet(Lu3Al5O(12):Ce^3+)green phosphors were synthesized by high temperature solidstate method using commercial lutetium(III)oxide,cerium(III)oxide,and as-prepared Al2O3 powders with different morphologies.The phases,morphologies,and photoluminescent properties of the prepared phosphors were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM),and photoluminescence spectroscopy(PL).Moreover,the influences of the morphologies ofα-Al2O3 on the types of crystal structure,morphologies,and photoluminescent properties of LuAG:Ce^3+green phosphors were investigated.The results indicated that the morphologies and particle sizes of theα-Al2O3 powders could be controlled by the additives and parameters.Notably,the sphericalα-Al2O3 powders with good dispersibility were found to be the excellent base materials of LuAG:Ce^3+green phosphors for white light emitting diodes. 展开更多
关键词 alumina particles hydrothermal-thermolysis morphology control cerium doped lutetium aluminum garnet phosphor
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Influence of carbon and yttrium co-doping on the photocatalytic activity of mixed phase TiO_2 被引量:5
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作者 Honglin Gao Jianmei Liu +3 位作者 Jin Zhang Zhongqi Zhu Genlin Zhang Qingju Liu 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第10期1688-1696,共9页
Mixed phase TiO2photocatalysts doped with C and Y were synthesized by a sol‐gel process.The effects of C and Y doping and annealing temperatures on the structural and optical properties,and photocatalytic activity we... Mixed phase TiO2photocatalysts doped with C and Y were synthesized by a sol‐gel process.The effects of C and Y doping and annealing temperatures on the structural and optical properties,and photocatalytic activity were investigated.We found that both C and Y doping can broaden the absorption spectrum of TiO2to the visible light region and inhibit recombination of photogenerated electron/hole pairs.The incorporation of Y into the TiO2lattice inhibited growth of crystalline grains,which increased the specific surface area and enhanced the photocatalytic activity.The photocatalytic performance of the samples was investigated in the photocatalytic degradation of methyl blue under visible light irradiation.The rate of methyl blue degradation over the(C,Y)‐co‐doped TiO2sample was much higher than those of undoped TiO2,C‐TiO2,and Y‐TiO2.Additionally,the apparent first‐order rate constant of the co‐doped sample was3.5times as large as that of undoped mix phase TiO2under the same experimental conditions.The enhanced photocatalytic activity can be attributed to the synergic effect of(C,Y)‐co‐doping and the formation of an appropriate crystalline structure. 展开更多
关键词 Titanium dioxide Co‐doping Mixed phase Phase control Visible light photocatalysis
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