检索结果-南通市图书馆

Journal of Palaeogeography 2021年第1期10卷 39-54页

作者： Yu-Chao Fan Yong-An Qi Ming-Yue Dai Da Li Bing-Chen Liu guo-shuai qing School of Resources and Environment Henan Polytechnic UniversityJiaozuo 454000Henan ProvinceChina

Bioturbation plays a critical role in sediment mixing and biogeochemical cycling between sediment and *** abundance of bioturbation structures, dominated by Thalassinoides, occurs in carbonate rocks of the Cambrian Series 2 Zhushadong Formation in the Dengfeng area of western Henan Province, North China. Determination of elemental geochemistry can help to establish the influence of burrowing activities on sediment biogeochemical cycling, especially on changes in oxygen concentration and nutrient regeneration. Results show that there is a dramatic difference in the bioturbation intensity between the bioturbated limestone and laminated dolostone of the Zhushadong Formation in terms of productivity proxies(Baex, Cu, Ni, Sr/Ca) and redox proxies(V/Cr, V/Sc, Ni/Co). These changes may be related to the presence of Thalassinoides bioturbators, which alter the particle size and permeability of sediments, while also increase the oxygen concentration and capacity for nutrient *** with modern studies shows that the sediment mixing and reworking induced by Thalassinoides bioturbators significantly changed the primary physical and chemical characteristics of the Cambrian sediment,triggering the substrate revolution and promoting biogeochemical cycling between sediment and seawater.

关键词： Thalassinoides Sediment mixing Oxygen concentration Nutrient regeneration Trace element proxy Early Cambrian North China Platform

Ancient Art Retains Splendor in New Era

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China Today 2025年第1期74卷 74-75页

作者： guo qing 不详

With government support,more young people are studying Thangka art,securing its innovative *** 1,300-year-old Thangka art,religious painting on woven material,has been lauded as an illustrated encyclopedia of Tibetan *** unique artistic and cultural value earned it a place on China’s intangible cultural heritage list in *** institution tasked with preserving and developing this ancient art is the Tibet Academy of Thangka(TAT)in *** focuses on the Mansar School of Thangka *** can observe the whole process of creating a Mansar Thangka piece,from sketching to adding the final touch.

关键词： religious earned sketch

China-India: Ties that Bind

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China Today 2025年第1期74卷 59-61页

作者： guo qing 不详

From international student to professor,Tripathi Mani shares his thoughts on Chinese and Indian cultures and the beneficial exchanges between *** Vivek Mani first learned about China from bedtime stories told by his father,a Sanskrit teacher in rural Bihar,a state in east *** of the stories were about the Chinese monk Xuanzang’s adventures during his long journey to India to find Buddhist *** kindled the young boy’s interest in China and the desire to visit it one day.

关键词： India Indian desire

Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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Journal of Energy Chemistry 2025年第1期100卷 710-720页

作者： Wenxuan Chen Xiu-qing Qiao guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian Wu Tao Wu Dong-Sheng Li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges Laboratory College of Chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-CdS/Mo2C@C heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the CdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-CdS （c-CdS） and hexagonal-CdS （h-CdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-CdS phase junction to realize gradient charge ***,the photothermal effect of Mo2C@C helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-CMC photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of CdS by constructing plasmonic tandem heterogeneous junctions.

关键词： Cadmium sulfide

The School that Changes Mindsets

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China Today 2025年第1期74卷 62-64页

作者： guo qing KONG SIQI 不详

China’s highest-altitude primary school is not only teaching children of farmers and herders but their parents as *** Sinopec Primary School in Nagqu,a city in Xizang Autonomous Region in southwest China,is known as the school“the closest to the sky”due to its high-altitude location-a breathtaking 4,700 meters above sea *** by oil and gas giant Sinopec as part of its corporate social responsibility,the school opened in 2012 and has since become a microcosm of China’s drive for education,especially in remote and rural areas,to ensure that no one is left behind.

关键词： altitude farmers southwest

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基于物联网的新书荐读系统设计

包装工程 2017年第20期38卷 32-36页

作者：许彧青王雪莹万明帅郭泽卿哈尔滨工程大学哈尔滨150001 武汉理工大学武汉430070

目的研究基于物联网的新书荐读系统并对其进行设计。方法依据对图书推广现状的分析和全民阅读调研数据的分析,应用物联网技术、热敏打印技术和B/S架构程序技术,实现新书荐读机终端与读者用户的交互,完成荐读图书数据的展示和用户行为信... 详细信息

目的研究基于物联网的新书荐读系统并对其进行设计。方法依据对图书推广现状的分析和全民阅读调研数据的分析,应用物联网技术、热敏打印技术和B/S架构程序技术,实现新书荐读机终端与读者用户的交互,完成荐读图书数据的展示和用户行为信息的获取。结论在物联网技术支持下,构建了新书荐读系统,其中的荐读服务平台将读者与出版社连接起来,荐读机终端为用户提供了新的图书推荐方式及纸质阅读体验,从而提高了用户阅读质量,并促进了新书推广。

关键词：图书推广物联网新书荐读系统热敏打印

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芯片硬件安全风险分析与防控建议

工业技术创新 2020年第3期7卷 18-23页

作者：翟腾高宏玲郭青帅工业和信息化部计算机与微电子发展研究中心(中国软件评测中心) 北京100048

芯片硬件安全性能是信息安全的基石,分析、防控和杜绝芯片内部和外部的相关安全风险隐患一直是重要研究课题。针对芯片面临的两大安全风险--硬件木马植入和物理攻击进行了探讨:一是以旁路信号分析检测硬件木马为典型案例,分析了物理检... 详细信息

芯片硬件安全性能是信息安全的基石,分析、防控和杜绝芯片内部和外部的相关安全风险隐患一直是重要研究课题。针对芯片面临的两大安全风险--硬件木马植入和物理攻击进行了探讨:一是以旁路信号分析检测硬件木马为典型案例,分析了物理检测、逻辑测试、旁路信号分析等硬件木马检测技术的优势和劣势;二是以使用简单功耗分析(SPA)和差分功耗分析(DPA)等攻击方式破解智能卡芯片密钥为典型案例,分析了非侵入式攻击、半侵入式攻击和侵入式攻击等物理攻击类硬件安全风险。基于风险识别提出了硬件安全防控建议:1)构建高集成度硬件木马仿真环境和模型库;2)重点关注产业链安全,加强环节控制;3)大力开展攻防技术研究,提升芯片抗攻击能力。

关键词：芯片风险识别安全管控硬件木马物理攻击旁路信号分析模型库产业链

基于FPGA的串口通信AES加密模块硬件木马设计与检测

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工业技术创新 2019年第6期6卷 32-37页

作者：郭青帅翟腾高宏玲工业和信息化部计算机与微电子发展研究中心(中国软件评测中心)

高级加密标准(Advanced Encryption Standard,AES)算法安全性强、可靠性高,但密钥仍有泄露可能,造成信息安全事件或事故。为了更好地检测和防范硬件木马,针对广泛应用的串口通信,基于FPGA开发板,首先,设计一款用于窃取AES加密模块密钥... 详细信息

高级加密标准(Advanced Encryption Standard,AES)算法安全性强、可靠性高,但密钥仍有泄露可能,造成信息安全事件或事故。为了更好地检测和防范硬件木马,针对广泛应用的串口通信,基于FPGA开发板,首先,设计一款用于窃取AES加密模块密钥的硬件木马,实现密钥获取;其次,鉴于硬件木马会导致器件功耗发生变化,采用基于功耗分析技术的侧信道分析方法,对硬件木马进行检测。搭建实验装置对设计方案进行测试,表明:1)该硬件木马能够使密钥信息发生泄露;2)含木马、无木马的电路频谱波形相关性较低,侧信道分析方法能够检测出硬件木马的侵入。

关键词：硬件木马高级加密标准(AES) 串口通信密钥侧信道分析

A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu Ming-Hui Chen Peng Zhao Wen-Bo Deng Ji Xiong Kai guo Ya-qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

关键词：

Quasi-synchronous control of uncertain multiple electrohydraulic systems with prescribed performance constraint and input saturation

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Chinese Journal of Aeronautics 2023年第9期36卷 416-425页

作者： shuai LI qing guo Yan SHI Yao YAN Dan JIANG School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

This article focuses on the high accuracy quasi-synchronous control issue of multiple electrohydraulic systems(MEHS).In order to overcome the negative effects of parameter uncertainty and external load interference of MEHS,a kind of finite-time disturbance observer(FTDO)via terminal sliding mode method is constructed based on the MEHS model to achieve fast and accuracy estimation and compensation *** avoid the differential explosion in backstepping iteration,the dynamic surface control is used in this paper to guarantee the follower electrohydraulic nodes synchronize to the leader motion with a better ***,a timevarying barrier Lyapunov function(tvBLF)is adopted during the controller design process to constraint the output tracking error of MEHS in a prescribed performance with time-varying exponential *** the initial state condition is relax by tvBLF,the input saturation law is also adopted during the controller design process in this paper to restrain the surges of input signals,which can avoid the circuit and mechanical structure damage caused by the volatile input *** MEHS experimental bench is constructed to verify the effectiveness of the theoretical conclusions proposed in this paper and the advantages of the proposed conclusions in this paper are illustrated by a series of contradistinctive experimental results.

关键词： Backstepping Dynamic surface Finite-time disturbance observer Input saturation Multiple Electrohydraulic Systems Output error constraint Quasi-synchronous control