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Blockchain-Enabled Privacy Protection and Access Control Scheme Towards Sensitive Digital Assets Management

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China Communications 2024年第7期21卷 224-236页

作者： duan pengfei Ma Zhaofeng Zhang Yuqing Wang Jingyu Luo Shoushan School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China

With the growth of requirements for data sharing,a novel business model of digital assets trading has emerged that allows data owners to sell their data for monetary *** the distributed ledger of blockchain,however,the privacy of stakeholder's identity and the confidentiality of data content are ***,we proposed a blockchainenabled privacy-preserving and access control scheme to address the above ***,the multi-channel mechanism is introduced to provide the privacy protection of distributed ledger inside the channel and achieve coarse-grained access control to digital ***,we use multi-authority attribute-based encryption(MAABE)algorithm to build a fine-grained access control model for data trading in a single channel and describe its instantiation in *** analysis shows that the scheme has IND-CPA secure and can provide privacy protection and collusion *** with other schemes,our solution has better performance in privacy protection and access *** evaluation results demonstrate its effectiveness and practicability.

关键词： access control data trading MAABE multi-channel privacy preserving

A novel structure of ultra-high-loading small moleculesencapsulated ZIF-8 colloid particles

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Nano Research 2024年第4期17卷 2929-2940页

作者： pengfei duan Yunhe An Xiaoxiao Wei Yanjie Tian Di Guan Xiangwen Liu Lanqun Mao Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100089China College of Chemistry Beijing Normal UniversityBeijing 100875China

The safety of nanoparticle-based drug delivery systems(DDSs)for cancer treatment is still a challenge,restricted by the intrinsic cytotoxicity of drug carriers and leakage of loaded ***,we propose a novel nanocarrier’s cytotoxicity avoidance strategy by synthesizing an encapsulation core–shell structure of zeolitic imidazolate framework-8(ZIF-8)-based colloid particles(CPs)with an amorphous ZIF-8 *** encapsulation structure achieves an ultra-high loading rate(LR)of 90%(i.e.,9 mg doxorubicin(DOX)per 1 mg ZIF-8)for DOX and the protection of DOX from ***,to deliver unit-dose drug,this ultra-high LR of 90%significantly reduces the usage of ZIF-8 to 1.2%(2 orders of magnitude)compared to that of DOX@ZIF-8 with a 10%LR,in which cytotoxicity of ZIF-8 could well below the safety limit and then be relatively ***,drug delivery efficacy,scale-up ability,and universality of this encapsulation structure have been further *** findings suggest the great potential of this ZIF-8-based encapsulation core–shell structure in the field of drug delivery.

关键词： metal-organic frameworks zeolitic imidazolate framework-8(ZIF-8) drug delivery nanoparticles nanostructures

Upconverting and downshifting circularly polarized luminescence in a superstructural helix

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Science China Chemistry 2024年第8期67卷 2571-2577页

作者： Honghan Ji Bin Wu Enquan Tian Chao Ren Xue Jin Liangliang Zhu pengfei duan CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology(NCNST)Beijing 100190China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China University of Chinese Academy of Sciences Beijing 101408China

The modulation of circularly polarized luminescence(CPL) has become an increasingly prominent area of research. In this study,we propose a unique “one-excitation-to-three-emissions” CPL system through the co-assembly of an upconversion system,incorporating one sensitizer(Pt(II) mesotetraphenyl tetrabenzoporphyrine, Pt TPBP) and two annihilators(R/S-DPA and R/SBDP) within liquid crystals. The chiral nature of the annihilators induces a transformation of the nematic liquid crystal into chiral nematic liquid crystals(N*LC), establishing an excellent chiral matrix. Upon the incorporation of the sensitizer Pt TPBP and subsequent excitation at 635 nm, the system demonstrates two independent triplet–triplet annihilation photon upconversion(TTA-UC) with the emission in blue and yellow, aided by thermally activated triplet–triplet energy transfer(TTET). This is accompanied by the simultaneous generation of upconverting circularly polarized luminescence(UC-CPL) and downshifting near-infrared circularly polarized luminescence(DS-CPL) originating from the residual luminescence of Pt TPBP. Remarkably,fine-tuning the ratio between the two annihilators allows the TTA-UC system to exhibit multicolor CPL emission with an amplified luminescence dissymmetry factor(glum, reaching up to 0.6). Our study unveils a previously unreported “one-excitation-to-three-emissions” system and provides a versatile strategy for modulating CPL emissions, surpassing conventional methodologies.

关键词： circularly polarized luminescence triplet–triplet annihilation upconversion near-infrared emission chiral nematic liquid crystal luminescence dissymmetry factor

Paired Assistance:Policy Rationale and Economic Performance as Illustrated by Xizang and Xinjiang

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China Economist 2024年第3期19卷 70-88页

作者： Li Xihui Wang Guiduo duan pengfei Huang Jixin Minzu University of China BeijingChina Pu’er University Pu’erChina

This study highlights the changing priorities of China’s paired assistance throughout the past decades,as well as its theoretical implications and economic growth effects for recipient *** panel data from 32 prefecture-level cities from 1990 to 2020,this study uses the multiperiod difference-in-differences approach to examine how paired assistance has contributed to economic growth in Xizang Autonomous Region and Xinjiang Uygur Autonomous *** findings indicate that,first,the implementation of the paired assistance policy has boosted economic growth in Xizang and ***,paired assistance has stimulated economic growth in recipient communities by improving ***,paired assistance has contributed to economic growth in recipient communities by providing improved public services such as education and *** to public services have a relatively smaller indirect effect in short term than infrastructure development on economic *** both education and healthcare are crucial to people’s quality of life in recipient *** paper has refined and broadened research on the effects of paired assistance,providing preference for future policymaking.

关键词： Chinese characteristics paired assistance multiperiod difference-in-differences assessment of policy effects

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航空颠覆性技术初探

航空学报 2024年第5期45卷 8-24,I0002页

作者：樊会涛段鹏飞袁成中国航空工业集团有限公司北京100027 航空工业未来机载武器技术协同创新中心北京100029 北京航空航天大学人工智能研究院北京100191

颠覆性技术凭借其所体现出的创新性和破坏性,持续引领人类生产生活和作战方式变革,在大国兴衰和文明演进过程中也发挥了重要作用。航空发展史上,出现了众多替代原有技术的颠覆性技术,深刻影响了航空的发展进程,塑造出了当今空中作战和... 详细信息

颠覆性技术凭借其所体现出的创新性和破坏性,持续引领人类生产生活和作战方式变革,在大国兴衰和文明演进过程中也发挥了重要作用。航空发展史上,出现了众多替代原有技术的颠覆性技术,深刻影响了航空的发展进程,塑造出了当今空中作战和民航运输的基本形态。当前,世界正处于新一轮工业革命和军事革命加速到来的十字路口,能否对于包含航空领域在内的各类颠覆性技术开展识别、研究和产业化,对于重塑未来社会形态和军事格局至关重要。本文从概念内涵、3个显著特征、识别与获取等方面浅谈了对颠覆性技术的认识,论述了颠覆性技术对前三次工业革命的重要影响,举例说明了历史上5个典型航空颠覆性技术带来的显著变革,分析了未来航空科技高能化和智能化复合发展的重要趋势,预判了材料制造、能源动力、信息电子和交叉融合4个领域9项可能的航空颠覆性技术及潜在影响,提出了发展航空颠覆性技术的若干建议,期待未来的航空颠覆性技术写上更多中国人的名字。

关键词：颠覆性技术航空科技材料制造能源动力信息电子交叉融合

吸气式高超声速机动飞行样式及其关键技术分析

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航空兵器 2024年第2期31卷 99-105页

作者：段鹏飞高书亮王恩亮王瀚航空工业未来机载武器技术协同创新中心北京100029 中国航空研究院北京100029 中国空空导弹研究院河南洛阳471009 北京航空航天大学北京100191

机动飞行性能是确保吸气式高超声速飞行器实现多种应用的关键能力之一,本文重点对吸气式高超声速飞行器机动能力特点进行研究。首先分析了国外吸气式高超声速飞行器的发展趋势,就其典型机动能力水平和机动样式进行了初步分析,以美国当... 详细信息

机动飞行性能是确保吸气式高超声速飞行器实现多种应用的关键能力之一,本文重点对吸气式高超声速飞行器机动能力特点进行研究。首先分析了国外吸气式高超声速飞行器的发展趋势,就其典型机动能力水平和机动样式进行了初步分析,以美国当前典型高超声速导弹项目为例,梳理了吸气式高超声速飞行器的典型机动应用样式。在此基础上,从总体设计、气动外形、飞发一体、制导控制、多场耦合等方面,梳理分析了确保和提升吸气式高超声速飞行器机动能力的关键支撑性技术。

关键词：高超声速飞行器吸气式机动能力气动外形飞发一体制导控制多场耦合

国外无人机空空打击作战典型样式及关键技术研究

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航空兵器 2024年第3期31卷 14-20页

作者：高书亮段鹏飞田浩袁成中国航空研究院北京100012 航空工业未来机载武器技术协同创新中心北京100029 中国空空导弹研究院河南洛阳471009

无人机在现代战争中正发挥着日益重要的作用。本文针对国外无人机用于现代空空作战的研究进展、典型作战样式及其关键技术进行了分析,梳理分析了当前国外无人机用于空空打击作战的典型装备和技术发展现状,结合当前国外无人机装备发展现... 详细信息

无人机在现代战争中正发挥着日益重要的作用。本文针对国外无人机用于现代空空作战的研究进展、典型作战样式及其关键技术进行了分析,梳理分析了当前国外无人机用于空空打击作战的典型装备和技术发展现状,结合当前国外无人机装备发展现状分析了无人机直接应用于空空打击作战的优势和劣势;基于当前国外典型无人机平台性能特点,提出了无人机参与空空打击作战的三类潜在典型应用样式;针对无人机用于空空打击作战的实际需要,分析了无人机应用于未来空空作战的关键支撑性技术。

关键词：无人机空空作战作战样式机载武器

全球化生产·症候式表达·类型化叙事:新世纪以来中国艺术电影的三种转向

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艺术探索 2024年第2期38卷 114-122页

作者：段鹏飞清华大学新闻与传播学院北京100084

新世纪以来,中国艺术电影的生存空间受到商业电影的进一步挤压。近二十年来,中国艺术电影不断调整制作思路,探索着如何实现国际电影节与国内电影市场、国际社会议题与本土社会现实之间的平衡,在生产机制、内容表达和叙事策略三个层面呈... 详细信息

新世纪以来,中国艺术电影的生存空间受到商业电影的进一步挤压。近二十年来,中国艺术电影不断调整制作思路,探索着如何实现国际电影节与国内电影市场、国际社会议题与本土社会现实之间的平衡,在生产机制、内容表达和叙事策略三个层面呈现出新的发展趋势。

关键词：新世纪中国艺术电影全球化症候类型化

A new technique to identify the handedness of single nanomaterial

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Science China Chemistry 2022年第3期65卷 423-424页

作者： pengfei duan CAS Center for Excellence in Nanoscience CAS Key Laboratory of Nanosystem and Hierarchical FabricationNational Center for Nanoscience and Technology(NCNST)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Chirality is an elemental property in living matter and nature,and it can be observed at various hierarchical levels from subatomic and molecular to supramolecular,nanoscopic,macroscopic,and galactic scale[1].Nowadays,nanoscalechiral substances attract much attention due to their unique ***,carbon nanotubes,a prototypical one-dimensional material with fascinating physical properties and significant applications[2].

关键词： properties property material