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2-Steps Preparation Activated Carbon from Solidago Canadensis:Carbonized by Electrial heating and Activated by Microwave Radiation

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Journal of Donghua University(English Edition) 2010年第6期27卷 786-791页

作者：罗来盛杨再福余阳周美华 college of Environmental Science and engineering Donghua University

The activated carbon(AC)was prepared from Solidago Canadensis(SC),an alien invasive *** plant was firstly carbonized under nitrogen at 400 ℃ for 90 min in an electrical furnace,and then the carbonized product was activated with KOH through microwave *** of KOH/C ratio,microwave power,microwave radiation time on the adsorption capacities and yield of AC were *** indicated that the optimum conditions were KOH/C ratio 2 g/g,microwave power 700 W,and microwave radiation time 6 *** carbonation process of SC was analyzed by thermogravimetry(TG).The pore structural parameters and surface functional groups of the AC were characterized by nitrogen adsorption-desorption and Fourier Transformed Infrared Spectroscopy(FTIR),*** activation yield,the surface area,the average pore size,and the average micropore size of AC prepared from optimum conditions were 53.75%,1 888 m2/g,0.567 nm,and 0.488 nm,*** adsorption amounts of AC were 302.4 mg/g for methylene blue and 1 470.27 mg/g for iodine.

关键词： Solidago Canadensis(SC) activated carbon microwave radiation KOH activating agent

Measurement of Residual Stress Field of Hardfacing Metal with RE Oxide and Its Numerical Simulation

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Journal of Rare Earths 2003年第6期21卷 669-674页

作者：杨庆祥姚枚 college of Materials Science and engineering Yanshan University

The temperature and residual stress fields of a medium-high carbon steel, welded by a cracking resistance electrode with rare earth (RE) oxide, were measured by thermo-vision analyzer and X-ray stress analyzer respectively. Meanwhile, the martensitic transformation temperatures of matrix, hard-face welding (hardfacing) metal welded by conventional hardfacing electrode and that welded by cracking resistance electrode with RE oxide were determined. According to the experimental data and the thermo-physical, mechanical parameters of materials, finite element method (FEM) of temperature and stress fields was established. In this FEM, the effect of martensitic transformation on residual stress of hardfacing metal of medium-high carbon steel was taken into account. The results show that, by adding RE oxide in the coat of hardfacing electrode, the martensitic transformation temperature can be decreased, so that the residual tensile stress on the dangerous position can be decreased. Therefore, the cracking resistance of hardfacing metal can be improved.

关键词： metal materials residual stress hardfacing metal martensitic transformation medium-high carbon steel numerical simulation rare earth oxide

Reconfigurable Logic Design of CORDIC Based FFT Architecture for 5G Communications

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Intelligent Automation & Soft Computing 2023年第6期36卷 2803-2818页

作者： C.Thiruvengadam M.Palanivelan Department of Electronics and Communication engineering Anjalai Ammal Mahalingam Engineering CollegeThiruvarur614403TamilnaduIndia Department of Electronics and Communication engineering Rajalakshmi Engineering CollegeChennai602105TamilnaduIndia

There are numerous goals in next-generation cellular networks(5G),which is expected to be available *** want to increase data rates,reduce end-to-end latencies,and improve end-user service *** networks need to change because there has been a significant rise in the number of base stations required to meet these needs and put the operators’low-cost constraints to the *** it can withstand interference from other wireless networks,and Adaptive Complex Multicarrier Modulation(ACMM)system is being looked at as a possible choice for the 5th Generation(5G)of wireless *** arithmetic units need to be used on the hardware side of multicarrier systems to do the pulse-shaping filters and inverse *** main goal of this study is to adapt complex multicarrier modulation(ACMM)for baseband transmission with low complexity and the ability to change *** found that this is the first recon-figurable architecture that lets you choose how many subcarriers a subband has while still having the same amount of hardware resources as ***,under the new design with a single selection line,it selects from a set of *** baseband modulating signal is evaluated and tested using a Field-Programmable Gate Array(FPGA)*** device is available from a commercial *** technology outperforms current technology in terms of computational com-plexity,simple design,and ease of ***,it has a higher power spectrum density,spectral efficiency,a lower bit error rate,and a higher peak to average power ratio than existing technology.

关键词： Error analysis pulse-shaping filters reconfigurable architectures FBMC OFDM UFMC

Long-Term Effects of Docosahexaenoic Acid-Bound Phospholipids and the Combination of Docosahexaenoic Acid-Bound Triglyceride and Egg Yolk Phospholipid on Lipid Metabolism in Mice

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Journal of Ocean University of China 2018年第2期17卷 392-398页

作者： CHE Hongxia CUI Jie WEN Min XU Jie Teruyoshi Yanagita WANG Qi XUE Changhu WANG Yuming college of Food Science and engineering Ocean University of China Department of Health and Nutrition Science Nishikyushu University college of Food Science and engineering Wuhan Polytechnic University

The bioavailability of docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA) depends on their chemical forms. This study investigated the long-term effects of DHA-bound triglyceride(TG-DHA), DHA-bound phospholipid(PL-DHA), and the combination of TG-DHA and egg yolk phospholipid(Egg-PL) on lipid metabolism in mice fed with a high-fat diet(fat levels of 22.5%). Male C57BL/6J mice were fed with different formulations containing 0.5% DHA, including TG-DHA, PL-DHA, and the combination of TG-DHA and Egg-PL, for 6 weeks. Serum, hepatic, and cerebral lipid concentrations and the fatty acid compositions of the liver and brain were determined. The concentrations of serum total triglyceride(TG), total cholesterol(TC), high-density lipoprotein cholesterol(HDL-c), and hepatic TG in the PL-DHA group and the combination group were significantly lower than those in the high-fat(HF) group(P < 0.05). Atherogenic index(AI) of the PL-DHA group was significantly lower than that of the combination group(P < 0.05). Hepatic TC level in the combination group was significantly lower than that in the HF group(P < 0.05), but no significant difference was observed between the combination group and the PL-DHA group. Both the PL-DHA and the combination groups showed significantly increased DHA levels in the liver compared with the HF group(P < 0.05). However, there were no obvious increases in the cerebral DHA levels in all DHA diet groups. These results suggest that PL-DHA was superior to the combination of TG-DHA and Egg-PL in decreasing the AI. Long-term dietary supplementation with low amount of DHA(0.5%) may improve hepatic DHA levels, although cerebral DHA levels may not be enhanced.

关键词： omega-3 fatty acid docosahexaenoic acid eicosapentaenoic acid lipid metabolism triglycerides phospholipids

Elevated Temperature Properties of Bamboo Shaving Reinforced Geopolymer Composites

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Journal of Renewable Materials 2023年第1期11卷 27-40页

作者： Xinli Zhang Jiayu Zhang Zuhua Zhang Yiqiang Wu Yingfeng Zuo college of Materials Science and engineering Central South University of Forestry and TechnologyChangsha410004China college of Civil engineering Hunan UniversityChangsha410082China

Geopolymer is a new alternative cement binder to produce *** the present study,a novel geopolymer composites containing bamboo shaving(0–2 wt.%)were fabricated and exposed to the temperatures of 200℃,400℃,600℃and 800℃.Physical properties,micro-structure,and mechanical strengths of the geopolymer composites were evaluated before and after heating in order to understand their thermal properties,which are essential for the use as building *** the temperature rises,the drying shrinkage and apparent porosity of the composites increase,while the compressive and bending strengths *** the temperature range of 200℃–800℃,the residual compressive strength rates of the geopolymer composite containning 2 wt.%bamboo shaving were respective 73.8%,61.47%,56.16%,and 29.56%,meanwhile,the residual flexural strength rates were respective 46.69%,8.68%,2.52%,and 2.33%.Correspondingly,the residual compressive strength rates of pure geopolymer were respective 72.81%,61.99%,54.55%,and 14.64%;the residual flexural strength rates were 48.87%,5.69%,3.22%,and 2.47%,*** electron microscope(SEM),optical microscope,and X-ray diffractometry(XRD)were applied to find the microscopic *** strength loss in the geopolymer composites was mainly because of the thermal degradation of bamboo shaving and shrinkage of geopolymer *** shaving has great potential as reinforcer in developing low-cost geopolymer composites and may be used for applications up to 400℃.

关键词： Geopolymer composites bamboo shaving mechanical properties high temperature microstructure

A Few Integrable Dynamical Systems,Recurrence Operators,Expanding Integrable Models and Hamiltonian Structures by the r-Matrix Method

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Communications in Theoretical Physics 2017年第10期67卷 463-470页

作者：张玉峰 Iqbal Muhammad 岳超 college of Mathematics China University of Mining and Technology college of Medical Information engineering Taishan Medical University

We extend two known dynamical systems obtained by Blaszak, et al. via choosing Casimir functions and utilizing Novikov-Lax equation so that a series of novel dynamical systems including generalized Burgers dynamical system, heat equation, and so on, are followed to be generated. Then we expand some differential operators presented in the paper to deduce two types of expanding dynamical models. By taking the generalized Burgers dynamical system as an example, we deform its expanding model to get a half-expanding system, whose recurrence operator is derived from Lax representation, and its Hamiltonian structure is also obtained by adopting a new way. Finally, we expand the generalized Burgers dynamical system to the （29-1）-dimensional case whose Hamiltonian structure is derived by Poisson tensor and gradient of the Casimir function. Besides, a kind of （29-1）-dimensional expanding dynamical model of the （29-1）-dimensionaJ dynamical system is generated as well.

关键词： r-matrix poisson tensor expanding dynamical system

An interpretation of wave refraction and its influence on foreshore sediment distribution

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Acta Oceanologica Sinica 2019年第5期38卷 151-160页

作者： Vincent Jayaraj Joevivek Nainarpandian Chandrasekar Ramakrishnan Jayangondaperumal Vikram Chandra Thakur Krishnan Shree Purniema Akshaya college of engineering and Technology Centre for GeoTechnology Manonmaniam Sundaranar University Francis Xavier engineering college Structure and Tectonics Group Wadia Institute of Himalayan Geology

To analyze the grain size and depositional environment of the foreshore sediments, a study was undertaken on wave refraction along the wide sandy beaches of central Tamil Nadu coast. The nearshore waves approach the coast at 45° during the northeast(NE) monsoon, at 135° during the southwest(SW) monsoon and at 90° during the non-monsoon or fair-weather period with a predominant wave period of 8 and 10 s. A computer based wave refraction pattern is constructed to evaluate the trajectories of shoreward propagating waves along the coast in different seasons. The convergent wave rays during NE monsoon, leads to high energy wave condition which conveys a continuous erosion at foreshore region while divergent and inept condition of rays during the SW and non-monsoon, leads to moderate and less energy waves that clearly demarcates the rebuilt beach sediments through littoral sediment transport. The role of wave refraction in foreshore deposits was understood by grain size and depositional environment analysis. The presence of fine grains with the mixed population, during the NE monsoon reveals that the high energy wave condition and sediments were derived from beach and river environment. Conversely, the presence of medium grains with uniform population, during SW and non-monsoon attested less turbulence and sediments were derived from prolong propagation of onshore-offshore wave *** upshots are apparently correlated with the in situ beach condition. On the whole, from this study it is understood that beaches underwent erosion during the NE monsoon and restored its original condition during the SW and non-monsoon seasons that exposed the stability of the beach and nearshore condition.

关键词： foreshore grain size wave refraction sediment transport beach India

Optimal Data Placement and Replication Approach for SIoT with Edge

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Computer Systems Science & engineering 2022年第5期41卷 661-676页

作者： B.Prabhu Shankar S.Chitra Department of Information Technology Er Perumal Manimekalai College of EngineeringHosur635117TamilnaduIndia Department of Computer Science and engineering Er Perumal Manimekalai College of EngineeringHosur63117TamilnaduIndia

Social networks(SNs)are sources with extreme number of users around the world who are all sharing data like images,audio,and video to their friends using IoT *** concept is the so-called Social Internet of Things(SIot).The evolving nature of edge-cloud computing has enabled storage of a large volume of data from various sources,and this task demands an efficient storage *** this kind of large volume of data storage,the usage of data replication using edge with geo-distributed cloud service area is suited to fulfill the user’s expectations with low *** major issue is the way to store the data and replicate these large data items optimally and allocate the request from the data center *** efficient storage of these data,we use edge server,which is part of the cloud server,in this ***,the data are distributed and stored with quick access,which will reduce the latency with *** proposed data placement approach learns with machine learning(ML)algorithm called radial basis kernel function assisted with support vector machine(RBF-SVM)to classify the data center for storing the user and friend’s data from the SIoT *** learning algorithms will be used to predict the workload of the data stored in the data center as either edge or cloud depending on the existing time *** data placement with dynamic nature is also optimized using the proposed dynamic graph partitioning(GP)method to meet the individual user’s demand of low latency with minimum *** way will keep the SIoT data placement efficient and effective over ***,this proposed data placement and replication approach introduces three kinds of innovations compared with the existing data placement approach.(i)Rather than storing the user data in a single cloud,this study uses the edge server closest to the SIoT devices for faster access with reduced response time.(ii)The classification algorithm called RBF-SVM is used to find storage for

关键词： Data placement data replication social network social internet of things edge computing cloud computing graph partitioning support vector machine machine learning radial basis function latency storage cost

Design concepts of an aircraft wing： composite and morphing airfoil with auxetic structures

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Frontiers of Structural and Civil engineering 2016年第4期10卷 394-408页

作者： P R BUDARAPU Sudhir Sastry Y B R NATARAJAN Department of Aerospace engineering Indian Institute of Science Bangalore 560 012 India Department of Aeronautical engineering College of Engineering Defence University Ethiopia Department of Aeronautical engineering Institute of Aeronautical Engineering Hyderabad India

This paper is categorized into two parts. （1） A frame work to design the aircraft wing structure and （2） analysis ofa morphing airfoil with auxetic structure. The developed design frame work in the first part is used to arrive at the sizes of the various components of an aircraft wing structure. The strength based design is adopted, where the design loads are extracted from the aerodynamic loads. The aerodynamic loads acting on a wing structure are converted to equivalent distributed loads, which are further converted point loads to arrive at the shear forces, bending and twisting moments along the wing span. Based on the estimated shear forces, bending and twisting moments, the strength based design is employed to estimate the sizes of various sections of a composite wing structure. A three dimensional numerical model of the composite wing structure has been developed and analyzed for the extreme load conditions. Glass fiber reinforced plastic material is used in the numerical analysis. The estimated natural frequencies are observed to be in the acceptable limits. Furthermore, the discussed design principles in the first part are extended to the design of a morphing airfoil with auxetic structure. The advantages of the morphing airfoil with auxetic structure are （i） larger displacement with limited straining of the components and （ii） unique deformation characteristics, which produce a theoretical in-plane Poisson＇s ratio of -1. Aluminum Alloy AL6061-T651 is considered in the design of all the structural elements. The compliance characteristics of the airfoil are investigated through a numerical model. The numerical results are observed to be in close agreement with the experimental results in the literature.

关键词： wing design aerodynamic loads morphing airfoil auxetic structures negative Poisson's ratio