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Chinese Journal of Polymer Science 2017年第9期35卷 1132-1142页

作者： wen-jin yu shu-man xu li zhang 傅强 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University Chengdu 610065 China

In this work, completely immiscible polyethylene/polyamidel2 （PE/PA12） blends were prepared by high shear extruder. The morphology and mechanical properties of the blends were investigated as a function of rotation speed. It was found that the high shear processing is an effective method to improve the dispersion of the PAl2 phase in PE matrix when PA 12 contents are 5 wt% and 10 wt%, and the dispersed phase particle size is reduced with the increase of rotation speed from 100 r/min to 500 r/min. However, with further increase of PAl2 content to 20 wt%, high shear processing has no effect on the phase morphology of the blends. Accordingly, a largely increased elongation at break and impact strength are observed for PE/PAl2/95/5 and PE/PA12/90/10 blends obtained at high rotation speeds but no effect on the property of PE/PAI2/80/20. Annealing experiment demonstrated that the obtained phase morphology is not stable thus compatibilizer should be introduced in the future work. This work could provide a guideline for the application of high shear processing in the preparation of polymer blends with huge polarity difference.

关键词： Immiscible polyethylene/polyamidel2 (PE/PA12) blends High shear processing Phase morphology

Cache-Enabled in Cooperative Cognitive Radio Networks for Transmission Performance

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Tsinghua Science and Technology 2020年第1期25卷 1-11页

作者： Jiachen Yang Chaofan Ma Jiabao man Huifang Xu Gan Zheng Houbing song School of Electrical and Information Engineering Tianjin UniversityTianjin 300000China Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLE11 3TUUK Department of Electrical ComputerSoftwareand Systems EngineeringEmbry-Riddle Aeronautical UniversityDaytona BeachFL 32114USA.

The proliferation of mobile devices that support the acceleration of data services(especially smartphones)has resulted in a dramatic increase in mobile traffic. Mobile data also increased exponentially, already exceeding the throughput of the backhaul. To improve spectrum utilization and increase mobile network traffic, in combination with content caching, we study the cooperation between primary and secondary networks via content caching. We consider that the secondary base station assists the primary user by pre-caching some popular primary ***, the secondary base station can obtain more licensed bandwidth to serve its own user. We mainly focus on the time delay from the backhaul link to the secondary base station. First, in terms of the content caching and the transmission strategies, we provide a cooperation scheme to maximize the secondary user’s effective data transmission rates under the constraint of the primary users target rate. Then, we investigate the impact of the caching allocation and prove that the formulated problem is a concave problem with regard to the caching capacity allocation for any given power allocation. Furthermore, we obtain the joint caching and power allocation by an effective bisection search algorithm. Finally, our results show that the content caching cooperation scheme can achieve significant performance gain for the primary and secondary systems over the traditional two-hop relay cooperation without caching.

关键词： cooperative cognitive radio network content caching power allocation

Coordinated chaos control of urban expressway based on synchronization of complex networks

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Chinese Physics B 2018年第11期27卷 672-682页

作者： Ming-bao Pang yu-man Huang School of Civil and Transportation Hebei University of Technology Tianjin 300401 China

We investigate the problem of coordinated chaos control on an urban expressway based on pinning synchronization of complex networks. A node coupling model of an urban expressway based on complex networks has been established using the cell transmission model（CTM）. The pinning controller corresponding to multi-ramp coordinated controller was designed by using the delayed feedback control（DFC） method, whose objective is to realize periodical orbits from chaotic states. The concrete pinning control nodes corresponding to the subsystems of regulating the inflows from the on-ramps to the mainline were obtained and the parameters of the controller were optimized by using the stability theory of complex networks to ensure the network synchronization. The validity of the proposed coordinated chaos control method was proven via the simulation experiment. The results of the examples indicated that the order motion on urban expressway can be realized, the wide-moving traffic jam can be suppressed, and the operating efficiency is superior to that of the traditional control methods.

关键词： pinning synchronization of complex networks multi-on-ramp metering of urban expressway chaos control delayed feedback control (DFC)

Effects of harvest intensity on the marketable organ yield,growth and reproduction of non-timber forest products(NTFPs):implication for conservation and sustainable utilization of NTFPs

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Forest Ecosystems 2021年第4期8卷 755-764页

作者： Ting Zhang Lizhong yu yuan man Qiaoling Yan CAS Key Laboratory of Forest Ecology and management Institute of Applied EcologyShenyang 110016China Qingyuan Forest CERN Chinese Academy of SciencesShenyang 110016China Agriculture and Rural Bureau of Luanping County Chengde 068250China

Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed *** of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of *** intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and ***,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study *** to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive ***:The biomass growth rates of marketable organ and plant growth of *** under light harvest intensity treatment were significantly higher than those under other harvest *** plant height growth and 1000-seed weight of *** under severe harvest intensity treatment were significantly lower than those under control ***:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of *** and ***,*** findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs ***

关键词： Araliaceae family Non-timber forest products Sustainable utilization Harvest intensity Plant regeneration Marketable organ yield

Investigation of combined degrader for proton facility based on BDSIM/FLUKA Monte Carlo methods

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Nuclear Science and Techniques 2022年第2期33卷 30-39页

作者： man-Fen Han Jin-Xing Zheng Xian-Hu Zeng Jun-song Shen Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The significant advantage of proton therapy over other particle-based techniques is in the unique physical characteristics of the Bragg *** can achieve a highly conformal dose distribution and maximize the probability of tumor control by varying the irradiation *** proton facilities use cyclotrons for fixed energy beam extraction and are equipped with degrader and collimator systems for energy modulation and emittance ***,interactions between charged particles and degrader materials inevitably cause beam loss and divergence and deteriorate beam performance,which present great challenges for downstream transport and clinical *** this work,we investigate a method of energy reduction by combining boron carbide and graphite in a degrader to obtain greater beam transmission at lower *** results demonstrate that the beam size and emittance at the exit of the combined degrader diverge less than those of multi-wedge one in the energy range of 70-160 ***,the transmission efficiency after the first dipole also shows improvements of 36.26%at 70 MeV and 70.55%at 110 *** a component with a high activity level,the degrader causes additional ambient radiation during *** induced radiation even remains several hours after system *** of material activation and induced radiation based on 1 h irradiation with a 400 nA beam current shows that the combined degrader has a definite advantage in shielding despite producing more secondary *** radioactivity and average ambient dose equivalent are reduced by 50%compared with the multiwedge degrader at the important cooling time of 1 *** 12 h and 24 h of cooling,the radiation levels of degraders decrease slightly due to the presence of long half-life residual *** average dose generated from the multi-wedge degrader is still 1.25 times higher than that of the combined one.

关键词： Proton therapy Degrader Boron carbide Transmission efficiency Radionuclide Ambient dose equivalent

A combination of chondroitinase ABC,glial cell line-derived neurotrophic factor,and Nogo A antibody delayed-release microspheres for the treatment of spinal cord injury

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Neural Regeneration Research 2011年第10期6卷 772-777页

作者： yu Zhang yueming song Department of Orthopedics West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

The purpose of this study was to evaluate the effect of poly（lactide-co-glycolic acid） delayed-release microspheres,which were prepared using glial cell line-derived neurotrophic factor（GDNF）,on the delayed-release,controllability,and protection of GDNF *** present study is the first to combine chondroitinase ABC,GDNF,and Nogo A antibody delayed-release microspheres for the treatment of spinal cord *** show that the combined therapy of chondroitinase ABC,GDNF,and Nogo A antibody microspheres can increase the immunoreaction of neurofilament 200 in the injured spinal cord,and this therapeutic effect was better than chondroitinase ABC,GDNF,or Nogo A antibody microspheres administered singularly.

关键词： glial cell line-derived neurotrophic factor microspheres poly(lactide-co-glycolic acid) spinal cord injury neural regeneration

Research on PM_(2.5) Concentration Prediction Algorithm Based on Temporal and Spatial Features

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Computers, Materials & Continua 2023年第6期75卷 5555-5571页

作者： song yu Chen Wang School of Computer Science and Engineering Central South UniversityChangsha410000China

PM2.5 has a non-negligible impact on visibility and air quality as an important component of haze and can affect cloud formation and rainfall and thus change the climate,and it is an evaluation indicator of air pollution *** PM2.5 concentration prediction based on relevant historical data mining can effectively improve air pollution forecasting ability and guide air pollution prevention and *** past methods neglected the impact caused by PM2.5 flow between cities when analyzing the impact of inter-city PM2.5 concentrations,making it difficult to further improve the prediction ***,factors including geographical information such as altitude and distance and meteorological information such as wind speed and wind direction affect the flow of PM2.5 between cities,leading to the change of PM2.5 concentration in *** a PM2.5 directed flow graph is constructed in this *** and meteorological data is introduced into the graph structure to simulate the spatial PM2.5 flow transmission relationship between *** introduction of meteorological factors like wind direction depicts the unequal flow relationship of PM2.5 between *** on this,a PM2.5 concentration prediction method integrating spatial-temporal factors is proposed in this paper.A spatial feature extraction method based on weight aggregation graph attention network(WGAT)is proposed to extract the spatial correlation features of PM2.5 in the flow graph,and a multi-step PM2.5 prediction method based on attention gate control loop unit(AGRU)is *** PM2.5 concentration prediction model WGAT-AGRU with fused spatiotemporal features is constructed by combining the two methods to achieve multi-step PM2.5 concentration ***,accuracy and validity experiments are conducted on the KnowAir dataset,and the results show that the WGAT-AGRU model proposed in the paper has good performance in terms of prediction accuracy and validates the effectiveness

关键词： Spatiotemporal fusion PM2.5 concentration prediction graph neural network recurrent neural network attention mechanism

Transgenic Expression of a Functional Fragment of Harpin Protein Hpa1 in Wheat Represses English Grain Aphid Infestation

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Journal of Integrative Agriculture 2014年第12期13卷 2565-2576页

作者： XU man-yu ZHOU Ting ZHAO Yan-ying LI Jia-bao XU Heng DONG Han-song ZHANG Chun-ling National Key Laboratory of Integrated management of Crop Diseases and Pests Ministry of Education/College of Plant Protection Nanjing Agricultural University

The harpin protein Hpa1 produced by the rice bacterial blight pathogen promotes plant growth and induces plant resistance to pathogens and insect pests. The region of 10-42 residues （Hpa110-42） in the Hpa1 sequence is critical as the isolated Hpa110-42 fragment is 1.3-7.5-fold more effective than the full length in inducing plant growth and resistance. Here we report that transgenic expression of Hpa110-42 in wheat induces resistance to English grain aphid, a dominant species of wheat aphids. Hpa110-42-induced resistance is effective to inhibit the aphid behavior in plant preference at the initial colonization stage and repress aphid performances in the reproduction, nymph growth, and instar development on transgenic plants. The resistance characters are correlated with enhanced expression of defense-regulatory genes （EIN2, PP2-A, and GSL10） and consistent with induced expression of defense response genes （Hel, PDF1.2, PR-1b, and PR-2b）. As a result, aphid infestations are alleviated in transgenic plants. The level of Hpa110-42-induced resistance in regard to repression of aphid infestations is equivalent to the effect of chemical control provided by an insecticide. These results suggested that the defensive role of Hpa110-42 can be integrated into breeding germplasm of the agriculturally signiifcant crop with a great potential of the agricultural application.

关键词： Hpa110-42 transgenic wheat resistance aphids chemical control

Investigation on martensitic steel using a quenching-partitioning-tempering process via electron backscatter diffraction analysis

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Science China(Technological Sciences) 2012年第3期55卷 646-651页

作者： CHEN song yu Hao School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

A new quenching-partitioning-tempering （Q-P-T） process was designed based on the recently developed quenching and partitioning （＆ P） treatment by Speer et al. The orientation relationships （ORs） of martensite （α） in Q-P-T steel tempered under different conditions were investigated using a scanning electron microscope with an electron backscatter diffraction unit. The morphology and crystallography of lath martensite within a packet were analyzed. Martensites exhibiting an initial austenite （y） grain in the orientation image map of different samples were chosen and their { 111 }α pole figures were drawn. The pole figures were fitted according to the ideal Kurdjumov-Sachs （K-S） and Nishiyama-Wasserman （N-W） ORs, which were calculated using Matlab and with a y crystal-oriented （001）γ[100]γ as the reference frame. The martensite OR in the Q-P-T steel follows both the K-S and N-W ORs; however, the K-S OR is predominant. This characteristic does not change in the samples further tempered at different temperatures.

关键词： quenching-partitioning-tempering process EBSD orientation relationship tempering

Protein sequence analysis based on hydropathy profile of amino acids

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第2期13卷 152-158页

作者： Xiao-li XIE Li-fei ZHENG Ying yu Li-ping LIANG man-cai GUO John song Zhi-fa yuAN College of Sciences Northwest A&F UniversityYangling 712100China College of Animal Science and Technology Northwest A&F University Yangling 712100 China College of Animal Science and Technology China Agriculture UniversityBeijing 100193China Department of Animal and Avian Sciences University of MarylandCollege ParkMD 20742USA

Biology sequence comparison is a fundamental task in computational *** to the hydropathy profile of amino acids,a protein sequence is taken as a string with three *** curves of the new protein sequence were defined to describe the protein sequence.A new method to analyze the similarity/dissimilarity of protein sequence was proposed based on the conditional probability of the protein ***,the protein sequences of ND6(NADH dehydrogenase subunit 6)protein of eight species were taken as an example to illustrate the new *** results demonstrated that the method is convenient and efficient.

关键词： Protein sequence Sequence comparison Similarity/dissimilarity Conditional probability