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绿氢标准、融资体系及中欧氢能合作路径分析

当代石油石化 2024年第6期32卷 11-16页

作者：胡明禹刘亦凡高蕙雯中国石化集团经济技术研究院有限公司中国石化咨询有限责任公司北京100029 中国石油大学(北京)机械与储运工程学院北京102299

欧美国家相继出台绿氢定义标准和草案,但全球范围内绿氢定义、范围要求、标准要求尚未达成共识,对未来开展跨国绿氢项目投融资和贸易带来一定阻力。欧盟是该领域的先行者,2023年率先成立了欧洲氢能银行,以刺激和支持本土氢能产业发展。... 详细信息

欧美国家相继出台绿氢定义标准和草案,但全球范围内绿氢定义、范围要求、标准要求尚未达成共识,对未来开展跨国绿氢项目投融资和贸易带来一定阻力。欧盟是该领域的先行者,2023年率先成立了欧洲氢能银行,以刺激和支持本土氢能产业发展。其设立初衷是帮助欧盟更好应对氢能项目发展初期的投资缺口,设计了4项功能机制:释放欧盟及第三国对氢能的投资(拍卖即服务)、扩大氢能进口、整合氢能融资政策、提升融资工具的协调性和效率。绿氢的碳属性和交易属性是支撑欧洲开展绿氢交易的关键依据和重要基础。全球碳中和大势下,氢能已日渐成为未来国际经济合作的重要领域,有望成为打造中欧能源绿色合作伙伴关系的新增长点。为此建议,加强绿氢标准合作和协调,推动国际互认和互用;多形式参与欧洲氢能银行合作,推动项目合作共建;加速建立全球氢能市场,开辟新型能源贸易关系;建立中国特色的氢能投资银行,整合现有金融资源。

关键词：绿氢欧洲氢能银行拍卖即服务绿氢融资体系绿氢标准

α受体阻滞剂对输尿管软镜碎石术中输尿管通道鞘置入影响的meta分析

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临床泌尿外科杂志 2024年第4期39卷 286-291,295页

作者：刘威刘一凡张旭辉山西医科大学第一医院泌尿外科太原030000

目的:α受体阻滞剂可以减少输尿管收缩力和蠕动频率,降低放置输尿管通道鞘(ureteral access sheath, UAS)的阻力。较小的置鞘阻力与更低程度的置鞘损伤有关,并增加置鞘成功的可能性。目前相关研究的质量参差不齐,研究结果间存在差异。... 详细信息

目的:α受体阻滞剂可以减少输尿管收缩力和蠕动频率,降低放置输尿管通道鞘(ureteral access sheath, UAS)的阻力。较小的置鞘阻力与更低程度的置鞘损伤有关,并增加置鞘成功的可能性。目前相关研究的质量参差不齐,研究结果间存在差异。通过系统回顾和meta分析,评价术前应用α受体阻滞剂在置鞘过程中的作用。方法:系统检索PubMed、Web of Science和Cochrane library数据库,时间截至2023年3月1日,查找关于术前应用α受体阻滞剂对UAS置入影响的临床研究。按照术前是否应用α受体阻滞剂分为试验组和对照组,研究的主要结果为UAS置入成功率;次要结果为输尿管损伤、术后结石清除率。结果:经过筛选后共纳入8篇研究,899例患者。分析显示,试验组的置鞘成功率显著高于对照组(RR=1.08,95%CI:1.04~1.13,P0.05)。依据输尿管损伤的PULS分级,对不同输尿管损伤等级进行亚组分析显示,≥0级输尿管损伤2组差异无统计学意义(RR=0.99,95%CI:0.86~1.13,P>0.05);≥1级输尿管损伤在试验组更低(RR=0.64,95%CI:0.44~0.93,P0.05)。2组具有相似的术后结石清除率(RR=1.04,95%CI:0.93~1.17,P>0.05)。结论:术前应用α受体阻滞剂可提高UAS置入成功率,可能与较低的输尿管损伤等级有关。坦索罗辛和西洛多辛在置鞘过程中的效应相似。

关键词： α受体阻滞剂输尿管通道鞘输尿管损伤 meta分析

Effect of system parameters on the size distributions of hollow nickel microspheres produced by an ultrasound-aided electrical discharge machining process

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Particuology 2014年第6期12卷 36-41页

作者： yifan liu Xianglong Li Fushi Bai Jian Chen Yantao Wang Nan liu School of Manufacturing Science and Engineering Sichuan University School of Mechanical and Manufacturing Engineering University of New South Wales

Ultrasound-aided electric discharge machining（EDM） is an emerging technology for producing hollow nickel *** technology combines traditional EDM with the cavitation and vibration effects of ultrasound to produce hollow *** this paper,ultrasound-aided EDM was carried out in a kerosene medium（the working solution）.The effects of various parameters on the sizes of microspheres were investigated using scanning electronic microscopy（SEM）.Smileview software was used to measure the sizes of the *** software was used for statistical analysis to determine the size distributions of the *** study the effects of the system parameters on the sizes of the microspheres,we first investigated the necessity of using an ultrasonic wave with *** comparing the experimental results with and without the ultrasonic field,we found that ultrasound-induced cavitation and vibration effects reduced the diameters of the *** then studied the effects of several electrical parameters,including the arc current,pulse width,and gap voltage,on the sizes of the microspheres at an ultrasound frequency of 40 *** microspheres could be obtained by lowering the arc current,pulse width,and gap voltage.

关键词： Hollow microspheres Ultrasonic-aided EDM Cavitation Electrical parameters Size distribution

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中国共产党坚定历史自信的价值与路径研究

湖南行政学院学报 2024年第3期 53-61页

作者：廖义军刘一凡湘南学院马克思主义学院湖南郴州423000 湖南工业大学马克思主义学院湖南株洲421007

深刻理解和正确把握中国共产党历史自信,应从历史自信的涵义、历史自信与中国共产党的关系来把握,结合“两个大局”“四个自信”“两个结合”“两个确立”来挖掘其价值,从“四个有利于”探索其实践路径。以期在中国共产党带领中国人民... 详细信息

深刻理解和正确把握中国共产党历史自信,应从历史自信的涵义、历史自信与中国共产党的关系来把握,结合“两个大局”“四个自信”“两个结合”“两个确立”来挖掘其价值,从“四个有利于”探索其实践路径。以期在中国共产党带领中国人民实现中华民族伟大复兴的进程中,更好地坚定历史自信。

关键词：中国共产党历史自信 “四个自信”

A Survey: Typical Security Issues of Software-Defined Networking

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China Communications 2019年第7期16卷 13-31页

作者： yifan liu Bo Zhao Pengyuan Zhao Peiru Fan Hui liu Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education School of Cyber Science and Engineering Wuhan University Wuhan 430072 China School of Cyber Security and Computer Hebei University Baoding 071002 China

Software-Defined Networking (SDN) has been a hot topic for future network development, which implements the different layers of control plane and data plane respectively. Despite providing high openness and programmability, the “three-layer two-interface” architecture of SDN changes the traditional network and increases the network attack nodes, which results in new security issues. In this paper, we firstly introduced the background, architecture and working process of SDN. Secondly, we summarized and analyzed the typical security issues from north to south: application layer, northbound interface, control layer, southbound interface and data layer. Another contribution is to review and analyze the existing solutions and latest research progress of each layer, mainly including: authorized authentication module, application isolation, DoS/DDoS defense, multi-controller deployment and flow rule consistency detection. Finally, a conclusion about the future works of SDN security and an idealized global security architecture is proposed.

关键词： software-defined networking network security global security security threat

3D Ni(Ⅱ)/Cu(Ⅱ) Supermolecular Frameworks Based on Pyridylamine and Fumarate Co-ligands Containing a Trinodal (4,5,6)-Connected Network and a (H2O)16 Water Cluster

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Chinese Journal of Chemistry 2013年第2期31卷 256-262页

作者： yifan Kang Qing liu Wenting Yin Wentao Zhang Ping liu Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Key Laboratory of Physico-Inorganic Chemistry of Shaanxi College of Chemistry and Material Science Northwest University Xi' an Shaanxi 710069 China

Two new complexes, [Ni（dpypda）（H2O）3].（fum）（l） and [Cu2（dpypda）2（fum）2],-8nH2O （2）（dpypda = N2,N4-di（pyridin-2-yl）pyrimidine-2,4-diamine, fum=fumarate）, have been synthesized and characterized by single-crystal X-ray diffraction. Complex 1 is a discrete unit, exhibiting a （4,5,6）-connected framework formed by hydrogen bonding interactions and electrostatic interactions between flee rum dianions and mononuclear [Ni（dpypda）（H2O）3]2＋ cations. However, in complex 2, two crystallographically independent rum dianions adopt the alternative mode of mixed monodentate bridging and chelating and bis（monodentate） bridging Cu（II） atoms to produce a one-dimensional （ID） infinite zigzag chain. And there are unique （H2O）16 water clusters which consist of one cyclic （H2O）4 tetramer and two cyclic （H2O）5 pentamer with six dangling water molecules in its 3D su- pramolecular framework. Both 1 and 2 are characterized by IR and elemental analysis, and the TG properties were also investigated for 2.

关键词： pyridylamine ligand fumarate anions hydrogen bonding water clusters

Experimental Study on Inert Gas-assisted Laser Cut Veneer Based on LOM

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Journal of Renewable Materials 2020年第12期8卷 1681-1689页

作者： Qingwei liu Chunmei Yang Qian Miao yifan liu Jiuqing liu Wenji Yu College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin150040China Forestry and Woodworking Machinery Engineering Technology Center Northeast Forestry UniversityHarbin150040China Research Institute of Wood Industry Chinese Academy of ForestryBeijing100091China

Based on the LOM(Laminated Object Manufacturing)process,an inert gas-assisted laser method for wood cutting was *** carbonization degree of wood surface was improved by the introduction of helium(He)gas,and the influence of process parameters on the carbonization layer of wood surface was solved,it was significance to reduce the post-processing of LOM and improve the quality of forming *** cherry wood veneer was used as the experimental material,under the condition of the same process parameters,the wood was cut with or without inert gas-assisted,and the influence factors of kerf quality were studied by variance *** results showed that under the same condition,compared with traditional laser processing,the kerf width was obviously reduced in the inert gas-assisted cut*** the He gas had oxygen-isolation and flame retardant effect,which prevented heat accumulation and *** micro morphology of the kerf surface showed that the flatness was better in the inert gas-assisted *** the excess heat was blown out by the cooling and purging of the gas,the phenomenon of oxidation and burning was reduced,the range of HAZ(heat affected zone)was reduced,and the carbonization phenomenon was obviously *** surface quality of kerf was improved *** to the analysis of variance,in addition to the effect of laser power,cutting speed and inert gas flow on the cutting width,the interaction between inert gas flow and laser power,laser power and cutting speed were also the main factors which affected the cutting *** feasibility of the combined inert gas and laser processing to improve wood cutting quality has been verified through experimental research,which provided a certain reference for the followup research on improving the wood processing quality.

关键词： Gas-assisted laser cutting cutting width veneer

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中药活性成分调控免疫细胞抗肺癌研究进展

药物评价研究 2024年第9期47卷 2157-2167页

作者：王成志刘一帆张晓青赵戈蕾韩亮李东东刘培民河南中医药大学第二临床医学院郑州大学第一附属医院中医科河南中医药大学第二附属医院肿瘤一区

肺癌是世界范围内最常见的呼吸道恶性肿瘤，因其较高的发病率和致死率，已严重危害人类的身心健康。中医药在抗肺癌综合治疗方面应用历史悠久，优势突出，疗效良好，而中药活性成分大多具有良好的抗肺癌作用。研究发现，一些中药活性成... 详细信息

肺癌是世界范围内最常见的呼吸道恶性肿瘤，因其较高的发病率和致死率，已严重危害人类的身心健康。中医药在抗肺癌综合治疗方面应用历史悠久，优势突出，疗效良好，而中药活性成分大多具有良好的抗肺癌作用。研究发现，一些中药活性成分可以通过靶向肺癌信号通路，调节肺癌肿瘤免疫微环境中巨噬细胞、自然杀伤细胞、髓系抑制细胞、T细胞、调节性T细胞以及树突状细胞等免疫细胞，改善肺癌肿瘤免疫微环境，提高免疫细胞的功能和活性，增强机体免疫功能，逆转机体免疫抑制状态，从而发挥抗肺癌治疗的作用。通过收集近年来国内外中药活性成分（淫羊藿多糖、丹参酮Ⅰ、黄芪甲苷、牡荆素、人参皂苷、薯蓣皂苷、姜黄素、丹参酮ⅡA、大黄素、黄芪多糖、红景天苷、灵芝多糖、白藜芦醇等）在抗肺癌治疗中的相关研究报道，从中药活性成分调节免疫细胞及其抗肺癌作用具体机制方面进行论述，以期为相关新型临床抗肺癌药物的研发提供新的理论依据。

关键词：中药活性成分免疫细胞肺癌淫羊藿多糖黄芪甲苷丹参酮ⅡA 姜黄素白藜芦醇

HAS QoE prediction based on dynamic video features with data mining in LTE network

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Science China(Information Sciences) 2017年第4期60卷 196-209页

作者： Fei WANG Zesong FEI Jing WANG yifan liu Zhikun WU School of Information Science and Engineering Beijing Institute of Technology

Evaluation of HTTP adaptive streaming(HAS) quality of experience(Qo E) over LTE network is a challenging topic because of multi-segment and multi-rate features of dynamic video sequences. Different from the traditional Qo E evaluation methods based on network parameters, this paper proposes the HAS Qo E prediction methods based on its dynamic video segment features with data mining. Considering the application requirement of the trade-off between accuracy and complexity, two sets of methodologies are designed to evaluate the HAS Qo E including regression and classification. In regression method, we propose the evolved PSNR(e PSNR) model using differential peak signal to noise ratio(d PSNR) statistics as the segment features to evaluate HAS Qo E. In classification method, we propose the improved weighted k-nearest neighbors(Wk NN)by using dynamic weighted mapping according to the position of video chunk to meet the dynamic segment and rate features of HAS. In order to train and test these methods, we build a real-time HAS video-on-demand(VOD) system in LTE network and do subjective test in different video scenes. With the mean opinion score(MOS), the regression and classification methods are trained to predict the HAS Qo E. The validated results show that the proposed e PSNR and Wk NN methods outperform other evaluation methods.

关键词： HTTP adaptive streaming(HAS) quality of experience(Qo E) regression classification data mining video-on-demand(VOD) long term evolution(LTE)