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Homomorphic Hashing Verification for Wireless Sensor Networks Rateless Codes Over-the-Air Programming

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Journal of Beijing Institute of Technology 2019年第1期28卷 109-118页

作者： Hao He Weidong Yi ming li Yongrui Chen School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences

The homomorphic hash algorithm(HHA)is introduced to help on-the-fly verify the vireless sensor network(WSN)over-the-air programming(OAP)data based on rateless *** receiver calculates the hash value of a group of data by homomorphic hash function,and then it compares the hash value with the receiving message *** the feedback channel is deliberately removed during the distribution process,the rateless codes are often vulnerable when they face security issues such as packets contamination or *** method prevents contaminating or attack on rateless codes and reduces the potential risks of decoding *** with the SHA1 and MD5,HHA,which has a much shorter message digest,will deliver more *** simulation results show that to transmit and verify the same amount of OAP data,HHA method sends 17.9% to 23.1%fewer packets than MD5 and SHA1 under different packet loss rates.

关键词： wireless sensor network(WSN) over-the-air programming rateless codes homomorphic hashing security

Synthesis and characterization of acetylated sept-D-glucopyranose carbamate as an oligosaccharide donor

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Chinese Chemical Letters 2014年第1期25卷 134-136页

作者： Chang-ming lian li-Ping Jiang Dong-liang liu Key Laboratory of Science & Technology of Eco-Textile Ministry of EducationCollege of ChemistryChemical Engineering & BiotechnologyDonghua University

An oligosaccharide donor, acetylated sept-o-glucopyranose tetradecyl carbamate, was designed and synthesized. This compound could be easily linked to hydroxyl-containing compounds through an Oglycosidic bond. Characte... 详细信息

关键词： Oligosaccharide donor Carbamate β-Cyelodextrin Acidic cleavage Characterization

Comparison of Pb and Cd adsorption to the surface coatings and surficial sediments collected in Xianghai Wetland

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Journal of Environmental Sciences 2005年第1期17卷 126-129页

作者： liYu WANGXiao-li WANGYue DONGDe-ming ZHANGHua-peng liQing-shan liXingchun CollegeofEnvironmentandResources JilinUniversityChangchun130023China Song-liaoRiverBasinWaterResourcesProtectionBureau Changchun130021China CollegeofEnvironmentandResources JilinUniversityChangchun130023China／／Song-LiaoRiverBasinWaterResourcesProtectionBureauChangchun130021China

Surface coatings and surficial sediments were obtained in four natural waters in Xianghai Wetland in China to study the role of surface coatings and surficial sediments in controlling the transporting and cycling of heavy metals in aquatic environments. Pb and Cd adsorption to the surface coatings and surficial sediments were measured under controlled laboratory conditions(mineral salts solution with defined speciation, ionic strength 0 05 mol/L, 25℃ and pH 6 0 for surface coatings; and 0 005 mol/L CaCl 2 solution, 25℃ and pH 6 0 for surficial sediments). The Langmuir adsorption isotherm was applied to estimate equilibrium coefficients of Pb and Cd adsorption to the surface coatings and surficial sediments, and the component analyses of surface coatings and surficial sediments were also carried out. Correlation analyses between the maximum adsorption of Pb and Cd(Г max ) and the components in the surface coatings and surficial sediments suggested that there was a statistically significant trend for Pb and Cd adsorption(Г max ) to the surface coatings to increase with increasing in contents of Fe and Mn oxides in the surface coatings and surficial sediments. And the metal adsorption abilities of surface coatings were much stronger than those of surficial sediments, highlighting that in the same water, i.e. at the same pH and initial metal concentrations, the metals(such as lead and cadmium) in supernatant were feasible to be adsorbed by surface coatings than surficial sediments. The more importance of surface coatings than surficial sediments for adsorbing and cycling of heavy metals in aquatic environments was evidenced.

关键词： surface coatings surficial sediments Pb Cd adsorption capabilities

A New Jatrophane Diterpenoid Ester from Euphorbia turczaninowii

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Chinese Chemical Letters 2006年第2期17卷 201-203页

作者： li Gen liU Ren Xiang TAN You ming GONG China Pharmaceutical University Nanjing 210009 Nanjing University Nanjing 210093

A new jatrophane diterpenoid ester （2S, 3S, 4R, 5R, 7S, 8R, 13R, 15R） - 3, 5, 7, 8, 15- pentaacetoxy-9, 14-dioxojatropha-6（17）, 11E-diene was isolated from the whole plant of Euphorbia turczaninowii Kar. ＆ Kit.. ... 详细信息

关键词： Euphorbia turczaninowii Kar. & Kit. jatrophane diterpenoid ester ( 2S 3S 4R 5R 7S,8R 13R 15R)-3 5 7 8 15-pentaacetoxy-9 14-dioxojatropha-6(17) llE-diene.

Toward resilient cloud warehousing via a blockchain-enabled auction approach

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Frontiers of Engineering Management 2023年第1期10卷 20-38页

作者： ming li Jianghong FENG Su Xiu XU Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Management Jinan UniversityGuangzhou 510632China School of Management and Economics Beijing Institute of TechnologyBeijing 100081China

Cloud warehousing service (CWS) has emerged as a promising third-party logistics service paradigm driven by the widespread use of e-commerce. The current CWS billing method is typically based on a fixed rate in a coarse-grained manner. This method cannot reflect the true service value under the fluctuating e-commerce logistics demand and is not conducive to CWS resilience management. Accordingly, a floating mechanism can be considered to introduce more flexible billing. A CWS provider lacks sufficient credibility to implement floating mechanisms because it has vested interests in terms of fictitious demand. To address this concern, this report proposes a blockchain-enabled floating billing management system as an overall solution for CWS providers to enhance the security, credibility, and transparency of CWS. A one-sided Vickrey–Clarke–Groves (O-VCG) auction mechanism model is designed as the underlying floating billing mechanism to reflect the real-time market value of fine-grained CWS resources. A blockchain-based floating billing prototype system is built as an experimental environment. Our results show that the O-VCG mechanism can effectively reflect the real-time market value of CWSs and increase the revenue of CWS providers. When the supply of CWS providers remains unchanged, allocation efficiency increases when demand increases. By analyzing the performance of the O-VCG auction and comparing it with that of the fixed-rate billing model, the proposed mechanism has more advantages. Moreover, our work provides novel managerial insights for CWS market stakeholders in terms of practical applications.

关键词： resilient cloud warehousing blockchain technology floating billing management system auction mechanism third-party logistics

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立式螺旋搅拌磨机磨矿介质动力学研究

中国矿业 2024年第9期33卷 212-220页

作者：李洋波何建成王芏卜张明祝启恒北矿机电科技有限责任公司北京100160 矿冶过程智能优化制造全国重点实验室北京100160 北京科技大学机械工程学院北京100083

针对传统单相模拟法在模拟立式螺旋搅拌磨机(以下简称“立磨机”)过程中的局限性,如可视化反映特征少、未考虑流体对介质的作用导致仿真精度低等问题。采用一种基于CFD-DEM固液耦合仿真的新方法,用于模拟立磨机湿磨的磨矿过程,该方法能... 详细信息

针对传统单相模拟法在模拟立式螺旋搅拌磨机(以下简称“立磨机”)过程中的局限性,如可视化反映特征少、未考虑流体对介质的作用导致仿真精度低等问题。采用一种基于CFD-DEM固液耦合仿真的新方法,用于模拟立磨机湿磨的磨矿过程,该方法能有效提高湿磨仿真的精度。首先建立立磨机的三维模型,以及完成参数标定的流体与介质颗粒,而后利用固液耦合仿真新方法对湿磨条件下磨筒内介质球的运动进行可视化仿真分析。结合室内试验,以主轴扭矩作为仿真精度的评价指标,并定义了一种区域介质球运动速度算法,描述了磨筒内介质球的运动规律,最后对比分析了磨矿过程中介质的法向作用力与切向作用力。研究结果表明:耦合模拟法仿真的轴向扭矩值与试验扭矩值的平均相对误差为6.98%;结果显示,介质运动的平均速度最大值和最小值分别为0.1646m/s与0.0112m/s,且速度梯度较大的位置位于螺旋搅拌叶片周围区域;介质接触时法向力是切向力的5倍。由此可知,耦合模拟法相比传统单相模拟法能有效提高仿真精度。螺旋搅拌叶片周围区域因速度梯度大,是矿物能被有效研磨的前提,研磨物质主要受到介质的挤压破碎作用。

关键词：立式螺旋搅拌磨机 CFD-DEM耦合模拟法可视化仿真磨矿介质动力学分析

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澳洲坚果油储藏期间氧化稳定性的研究

中国粮油学报 2024年第3期39卷 133-140页

作者：李康宁张雪怡常明周葵张雅媛刘睿杰王兴国江南大学食品学院无锡214122 广西农业科学院农产品加工研究所南宁530007

以热榨澳洲坚果油为原料,以酸价、过氧化值、K232值、K268值和氧化诱导时间为氧化稳定性指标,采用Schaal烘箱加速法研究60℃下不同储藏阶段澳洲坚果油的氧化稳定性,同时研究储藏期间脂肪酸组成和总酚、总甾醇等脂质伴随物的变化。结果表... 详细信息

以热榨澳洲坚果油为原料,以酸价、过氧化值、K232值、K268值和氧化诱导时间为氧化稳定性指标,采用Schaal烘箱加速法研究60℃下不同储藏阶段澳洲坚果油的氧化稳定性,同时研究储藏期间脂肪酸组成和总酚、总甾醇等脂质伴随物的变化。结果表明:酸价从(0.36±0.05)mg KOH/g升高至(1.78±0.09)mg KOH/g,升高4.94倍;过氧化值从(0.0047±5.72×10^(-5))g/100 g升高至(0.0196±2.52×10^(-4))g/100 g,升高4.17倍;K232值从0.41±0.01升高至0.47±0.01,K268值变化不明显;氧化诱导时间从4.37 h下降至2.59 h,缩短1.68倍。储藏过程中澳洲坚果油脂肪酸组成基本未发生变化;总酚含量从33.45μg GAE/g减少至20.94μg GAE/g,减少1.59倍;总甾醇含量变化趋势较小。因此,澳洲坚果油储藏过程中,品质和稳定性均在不同程度上降低,多酚在澳洲坚果油中起到一定的抗氧化作用,虽然澳洲坚果油的氧化稳定性逐渐降低,但较大豆油、菜籽油等其他植物油相比,其仍具有更好的氧化稳定性。

关键词：澳洲坚果油储藏氧化稳定性脂质伴随物

Applications of LA-ICP-MS in the elemental analyses of geological samples

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Chinese Science Bulletin 2013年第32期58卷 3863-3878页

作者： liU YongSheng HU ZhaoChu li ming GAO Shan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS),which is a rapidly developing analytical technique for the analyses of trace elements and isotopes,plays an important role in advancing the study of Earth science,especially with respect to *** article reviews the application of LA-ICP-MS in the elemental analysis of solid geological *** LA-ICP-MS has been widely used in the spatial resolution analysis of element compositions and rapid bulk analysis of whole-rock and soil samples,the analysis accuracy is restricted by numerous factors,including the instrumental conditions,the elemental fractionation and matrix effects,the lack of sufficient matrix-matched reference materials,and the strategies for quantitative calibration and sensitivity drift *** to the type of samples and the analyte elements,the analysis accuracy can be improved through the optimization of instrument conditions and the adoption of suitable correction strategies and reference materials.

关键词： LA-ICP-MS 痕量元素分析应用地质样品电感耦合等离子体质谱基质效应校正策略分析精度

^(40)Ar/^(39)Ar Thermochronology Constraints on Jurassic Tectonothermal Event of Nyainrong Microcontinent

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Journal of Earth Science 2014年第1期25卷 98-108页

作者： Chaoming Xie Cai li Yanwang Wu ming Wang Peiyuan Hu College of Earth Science Jilin University

To reveal the Jurassic tectonothermal event occurring to the Nyainrong microcontinent which is gripped among the Bangong-Nujiang suture zone,^40Ar/^39Ar dating was carried out on the basement orthogneiss and Jurassic granitc gneiss in the microcontinent. In the heating stage, four sam- pies exhibited a flat plateau age, with the value Tp concentrated in the range of 166-176 Ma; isochron age Ti was concentrated in the range of 165-175 Ma, and their corresponding ages were the consistent within allowable range. The ages should be representative of the era of the final deformation of the Amdo gneiss and cooling emplacement of the magmatic rock in the Jurassic. The geochronological studies have shown that the final deformation of microcontinent crystalline basement and the cooling of the Mesozoic large-scale tectonothermal events occurred in late Middle Jurassic. In Middle Jurassic, Nyainrong microcontinent experienced strong tectonic movement. Combining with the geochronologi- cal with isotope geochemistry for the microcontinent, the cause of the tectonothermal event should be attributed to the collision between the Nyainrong microcontinent and South Qiangtang Block following the northward subduction of Bangong-Nujiang oceanic crust.

关键词： Tibet Plateau Nyainrong microcontinent Jurassic tectonothermal event, ^40Ar/^39Ar thermochronology.