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主动监听中协议欺骗的研究

通信学报 2003年第11期24卷 146-152页

作者：贺龙涛方滨兴胡铭曾哈尔滨工业大学国家计算机信息安全重点实验室国家计算机网络与信息安全管理中心北京100031

提出了基于协议欺骗的主动监听框架,大大扩展了网络监听的适用范围。分析了网络访问的具体过程,将其中存在的映射关系分为四种:服务器域名到IP地址、IP到MAC地址、远程服务器的IP地址到本地路由器IP地址、以及客户端界面显示到应用服务... 详细信息

提出了基于协议欺骗的主动监听框架,大大扩展了网络监听的适用范围。分析了网络访问的具体过程,将其中存在的映射关系分为四种:服务器域名到IP地址、IP到MAC地址、远程服务器的IP地址到本地路由器IP地址、以及客户端界面显示到应用服务器的处理。依据破坏的映射关系不同,本文将能够实现主动监听的协议欺骗分为四大类:ARP欺骗、路由欺骗、DNS欺骗和应用层欺骗,并详细分析了这四类协议欺骗攻击原理、实现方式及其防范策略。

关键词：主动监听协议欺骗 ARP欺骗 DNS欺骗路由欺骗应用层欺骗

丙烯酸β-羧乙酯-苯乙烯共聚物缩合异烟肼的合成及其水解释放研究

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高分子材料科学与工程 1989年第6期5卷 30-35页

作者：陈星胡力平焦书科北京化工学院应用化学系

本文利用丙烯酸β-羧乙酯一苯乙烯共聚物作为大分子载体,将抗结核药物(异烟肼)通过大分子化学反应载于大分子上,产率可达61％。该药物于36℃进行中性-酸性水解,得到了水解速度随酸性增大而缓慢增加的预期结果。

关键词：异烟肼大分子载体缩合控制释放

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椭圆型差分方程的并行迭代算法

数值计算与计算机应用 1993年第3期14卷 220-228页

作者：刘兴平北京应用物理与计算数学研究所

由于当代超级计算机技术日新月异地发展,研究出适应超级计算机运行的高效的计算方法是当务之急.现在已有许多著名学者对三对角方程组的解法(如文献)进行了讨论或用多色排序形成的线性代数方程组Ax=b使某些算法可并行计算(如文献。

关键词：差分方程椭圆型并行迭代算法

SOLID-STATE ELECTROCHROMIC DISPLAY

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Chinese Chemical Letters 1992年第4期3卷 323-324页

作者： Sheng Shui ZHANG~*, Wei Hua CHOU, Xin Ping QIU, Qing Guo LIU Laboratory of Solid State Iordcs, University of Science and technology beijing, 100083 Lei Ling YANG, and Bao Quan {2. beijing Research institute of Chemical Industry, 100013

A novel electrochromic display composed of polymeric solid electrolyte and ferroin electroactive species has been assembled, which presents a reversible variation of the color between light blue and red when a potential of 0.98 and 0.75 V is applied respectively. The results indicate that the response speed is increased by lowering the concentration of ferroin without decreasing color contrast.

关键词： SCE ELECTROSYNTHESIS OF SOME ORGANIC COMPOUNDS WITH CO2.CATALYZED BY CoTPP ELECTROCARBOXYLATION OF ORGANIC COMPOUNDS WITH CARBON DIOXIDE CATALYZED BY METALLOPORPHYRINS CO

Constructing efficient bacterial cell factories to enable one-carbon utilization based on quantitative biology:A review

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Quantitative Biology 2024年第1期12卷 1-14页

作者： Yazhen Song Chenxi Feng Difei Zhou Zengxin Ma Lian He Cong Zhang Guihong Yu Yan Zhao Song Yang Xinhui xing School of Life Sciences Shandong Province Key Laboratory of Applied Mycologyand Qingdao International Center on Microbes Utilizing BiogasQingdao AgriculturalUniversityQingdaoChina Department of Chemical Engineering University of WashingtonSeattleWashingtonUSA Key Laboratory of Systems Bioengineering Ministry of EducationTianjin UniversityTianjinChina Key Laboratory of Industrial Biocatalysis Ministry of EducationDepartment of Chemical EngineeringTsinghua UniversityBeijingChina Center for Synthetic and Systems Biology Tsinghua UniversityBeijingChina institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate Schooland Insttute of Biomedical Health Technology and EngineeringShenzhen Bay LaboratoryShenzhenChina

Developing methylotrophic cell factories that can efficiently catalyze organic one-carbon(C1)feedstocks derived from electrocatalytic reduction of carbon dioxide into bio-based chemicals and biofuels is of strategic significance for building a carbon-neutral,sustainable economic and industrial *** the rapid advancement of RNA sequencing technology and mass spectrometer analysis,researchers have used these quantitative microbiology methods extensively,especially isotope-based metabolic flux analysis,to study the metabolic processes initiating from C1 feedstocks in natural C1-utilizing bacteria and synthetic C1 *** paper reviews the use of advanced quantitative analysis in recent years to understand the metabolic network and basic principles in the metabolism of natural C1-utilizing bacteria grown on methane,methanol,or *** acquired knowledge serves as a guide to rewire the central methylotrophic metabolism of natural C1-utilizing bacteria to improve the carbon conversion efficiency,and to engineer non-C1-utilizing bacteria into synthetic strains that can use C1 feedstocks as the sole carbon and energy *** progresses ultimately enhance the design and construction of highly efficient C1-based cell factories to synthesize diverse high value-added *** integration of quantitative biology and synthetic biology will advance the iterative cycle of understand–design–build–testing–learning to enhance C1-based biomanufacturing in the future.

关键词： ^(13)C-metabolic flux analysis methylotrophic cell factories one-carbon feedstock quantitative biology

Dispersive liquid-liquid microextraction combined with high-performance liquid chromatography-diode array detection for the determination of sulfonamides in honey

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Dispersive liquid-liquid microextraction combined with high-...

Superhydrophobic melamine sponge prepared by radiation-induced grafting technology for efficient oil-water separation

西北地区第六届色谱学术报告会甘肃省第十一届色谱年会

作者： Xiaofeng Chi~(1,2.,Qi Dong~1,Yuxiu xing~(1,2.,Li Pi~1,Yuancan Xiao~1,Fengzu Hu~(1*) 1 Northwest institute of Plateau Biology of Chinese Academy of Sciences,Xining 810008{2. 2.Graduate school of Chinese Academy of sciences,beijing 100049,china

Dispersive liquid-liquid microextraction(DLLME) combined with high-performance liquid chromatography-diode array detection(HPLC-DAD) has been successfully developed for the extraction and determination of sulfonamides in honey *** effects of parameters such as the nature and volume of extraction solvent and dispersive solvent,extraction time,ionic strength and solution pH were *** this proposed method,1.0mL of acetonitrile(as dispersive solvent) containing 40μL 1,1,2.2.tetrachloroethane(as extraction solution) was rapidly injected into a 5.00mL honey sample containing the analytes,thereby forming a cloudy *** extraction,phase separation was performed by centrifugation and the enriched analytes in the sedimented phase were determined by *** the optimal conditions,the detection limit of the method was 0.8-1.5μgkg and the relative standard deviations(RSD%) for determination of the sulfonamides were in the range of *** was found to be in the range of 0.1-10.0μg mL;also,the enrichment factors were in the range of ***,the method was applied to determine the trace amounts of the sulfonamides in three real honey samples and satisfactory results were obtained.

关键词： Dispersive liquid-liquid microextraction(DLLME) Sulfonamides High-performance liquid chromatography Honey sample

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Nuclear Science and Techniques 2024年第9期35卷 103-114页

作者： Ying Sun Wen-Rui Wang Dan-Yi Li Si-Yi Xu Lin Lin Man-Li Lu Kai Fan Chen-Yang xing Lin-Fan Li Ji-Hao Li Shanghai institute of applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Architecture and Materials Chongqing College of Electronic EngineeringChongqing 401331China Center for Stretchable Electronics and NanoSensors Key Laboratory of Optoelectronic Devices and Systems of Ministry of EducationCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

This paper presents a superhydrophobic melamine(ME)sponge(ME-g-PLMA)prepared via high-energy radiation-induced in situ covalent grafting of long-alkyl-chain dodecyl methacrylate(LMA)onto an ME sponge for efficient oil–water *** obtained ME-g-PLMA sponge had an excellent pore structure with superhydrophobic(water contact angle of 154°)and superoleophilic *** can absorb various types of oils up to 66–168 times its *** ME-g-PLMA sponge can continuously separate oil slicks in water by connecting a pump or separating oil underwater with a gravity-driven *** addition,it maintained its highly hydrophobic properties even after long-term immersion in different corrosive solutions and repeated oil *** modified ME-g-PLMA sponge exhibited excellent separation properties and potential for oil spill cleanup.

关键词： Radiation-induced graft polymerization Oil–water separation Sponge Superhydrophobic

Spontaneous ignition of corrugated cardboard under dynamic high radiant flux

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Defence technology（防务技术） 2024年第10期40卷 65-77页

作者： Liu Liu Yan Gu Hong Yang xing Wang Yang Zhou Xiaogan Dai Yong Han Shanggang Wen Ming Li Congmei Lin Changgen Feng Fei Tang Yushi Wen institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999China State Key Laboratory of Explosion Science and technology Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China institute of applied Physics and Computational Mathematics China Academy of Engineering PhysicsBeijing 100088China

Understanding the response of solid combustibles under high radiant fluxes is critical in predicting the thermal damage from extreme *** the more moderate radiant fluxes in conventional hydrocarbon fires,extreme events such as strong explosion,concentrated sunlight and directed energy can generate dynamic radiant fluxes at the MW/m^(2. level,creating a unique threat to *** study investigates the pyrolysis and spontaneous ignition behaviors of corrugated cardboard by using both experimental and numerical methods,under 10-cm dynamic high radiant fluxes ranging from 0.2.to 1.2. MW/m^(2. for 10 *** spontaneous ignition process at dynamic high radiant fluxes was recorded and *** ignition modes were found at the critical radiant flux of 0.4 MW/m^(2.,namely hot-gas spontaneous ignition and hot-residue piloted *** latter is not the focus of this paper due to its extremely small probability of *** research reveals that the increase in flux intensity induces shorter delay times for both pyrolysis and ignition,lower ignition energy density,along with a corresponding rise in the critical mass flux and surface temperature at ignition *** simulation results are generally aligned with the experimental findings,despite some divergences may be attributed to model simplifications and parameter *** work contributes to a deeper insight into material behavior under extreme radiation,with valuable implications for fire safety and hazard assessment.

关键词： Extreme radiation Fire safety Corrugated cardboard Pyrolysis Ignition temperature

Critical state-induced emergence of superior magnetic performances in an iron-based amorphous soft magnetic composite

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Materials Futures 2024年第2期3卷 149-160页

作者： Liliang Shao Rongsheng Bai Yanxue Wu Jing Zhou xing Tong Hailong Peng Tao Liang Zongzhen Li Qiaoshi Zeng Bo Zhang Haibo Ke Weihua Wang Songshan Lake Materials Laboratory Dongguan 523808People’s Republic of China institute of Physics Chinese Academy of SciencesBeijing 100190People’s Republic of China School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 100096People’s Republic of China School of Materials Science and Engineering Central South UniversityChangsha 410083People’s Republic of China Center for High Pressure Science and technology Advanced Research Shanghai 201203People’s Republic of China Jiangsu JITRI Advanced Energy Materials Research institute Co. LtdChangzhou 213000People’s Republic of China

Soft magnetic composites(SMCs)play a pivotal role in the development of high-frequency,miniaturization and complex forming of modern ***,they usually suffer from a trade-off between high magnetization and good magnetic softness(high permeability and low core loss).In this work,utilizing the order modulation strategy,a critical state in a FeSiBCCr amorphous soft magnetic composite(ASMC),consisting of massive crystal-like orders(CLOs,∼1 nm in size)with the feature ofα-Fe,is *** critical-state structure endows the amorphous powder with the enhanced ferromagnetic exchange interactions and the optimized magnetic domains with uniform orientation and fewer micro-vortex *** comprehensive soft magnetic properties at high frequency emerge in the ASMC,such as a high saturation magnetization(Ms)of 170 emu g^(-1)and effective permeability(µ_(e))of 65 combined with a core loss(Pcv)as low as 70 mW cm^(-3)(0.01 T,1 MHz).This study provides a new strategy for the development of high-frequency ASMCs,possessing suitable comprehensive soft magnetic performance to match the requirements of the modern magnetic devices used in the third-generation semiconductors and new energy fields.

关键词： amorphous soft magnetic composites critical state soft magnetic property rotating magnetic field annealing magnetic domain