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Application and safety assessment for nano-composite materials in food packaging

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Chinese Science Bulletin 2011年第12期56卷 1216-1225页

作者： HAN Wei YU YanJun LI NingTao wang libing The Hazardous Products Central Laboratory General Administration of Quality Supervision Inspection and Quarantine of the People's Republic of China Tianjin 300042 China Technical Center for Safety of lndustrial Products Tianjin Entry-Exit Inspection and Quarantine Bureau of China Tianjin 300042 China Hunan Entry-Exit Inspection and Quarantine Bureau of China Changsha 410004 China

The technical breakthroughs and rapid developments in nanotechnologies enabling goods and products based on nanomaterials (NMs) has come to media and public attention as potentially one of the most significant technological advances of our time. Among these technical applications, nano-composite food packaging, which combines the NMs and conventional packaging, is at the forefront of applications in nanotechnologies, leading the whole industrial chain based on nanotechnologies with high speed development. Taking into account the status of the nano-composites applied in food packaging and present development trends, this review is focused on summarizing the basic applications of the nano-composites in food packaging as well as its risk assessment. The status summaries and the conclusions derived from this review are of benefit to manufacturers which produce the nano-composites used in food packaging, to general consumers and to governmental administration entities.

关键词：纳米复合材料食品包装应用安全评估纳米技术纳米材料技术进步发展趋势

Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China

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Chinese Geographical Science 2024年第1期34卷 67-78页

作者： HU Bo WEN Qingke XI Fengjiang LI Mengyao wang libing REN Yuejuan Aerospace Information Research Institute Chinese Academy of SciencesBeijing100094China University of Chinese Academy of Sciences Beijing100049China Inner Mongolia Remote Sensing Center Co. Ltd.Huhhot010000China Xilinhot the Maodeng pasture Xilinhot026000China China University of Mining and Technology Xuzhou221116China Shanxi Provincial Key Lab of Resources Environment and Disaster MonitoringCoal Geological Geophysical Exploration Surveying&Mapping Institute of Shanxi ProvinceJinzhong030600China

Grasslands in northern China serve the country as both an ecological barrier and a livestock production ***,installing enclosures has been becoming the major grassland restoration measure adopted by many local ***,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration ***,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to *** results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland *** the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to *** to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 *** livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in *** the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown *** capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in *** on grassland resources to develop the pastoral ecology also broadens the potential economic development ***,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s develo

关键词： enclosure grassland ecological benefit economic benefit Maodeng pasture Inner Mongolia northern China

A Joint Power and Bandwidth Allocation Method Based on Deep Reinforcement Learning for V2V Communications in 5G

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China Communications 2021年第7期18卷 25-35页

作者： Xin Hu Sujie Xu libing wang Yin wang Zhijun Liu Lexi Xu You Li Weidong wang School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China China Unicom Research Institute Beijing 100032China Department of Geomatics Engineering University of CalgaryAB T2N 1N4Canada

Vehicular communications have recently attracted great interest due to their potential to improve the intelligence of the transportation *** maintaining the high reliability and low latency in the vehicle-to-vehicle(V2V)links as well as large capacity in the vehicle-to-infrastructure(V2I)links,it is essential to flexibility allocate the radio resource to satisfy the different requirements in the V2V *** paper proposes a new radio resources allocation system for V2V communications based on the proximal strategy optimization *** this radio resources allocation framework,a vehicle or V2V link that is designed as an *** through interacting with the environment,it can learn the optimal policy based on the strategy gradient and make the decision to select the optimal sub-band and the transmitted power *** the proposed method can output continuous actions and multi-dimensional actions,it greatly reduces the implementation complexity of large-scale communication *** simulation results indicate that the allocation method proposed in this paper can meet the latency constraints and the requested capacity of V2V links under the premise of minimizing the interference to vehicle-to-infrastructure communications.

关键词： 5G V2V communication power allocation bandwidth allocation deep reinforcement learning

Transcriptome and physiological analyses provide insights into the leaf epicuticular wax accumulation mechanism in yellowhorn

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Horticulture Research 2021年第1期8卷 1851-1863页

作者： Yang Zhao Xiaojuan Liu Mengke wang Quanxin Bi Yifan Cui libing wang State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of Forestry100091 BeijingChina State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyChinese Academy of Sciences100101 BeijingChina University of Chinese Academy of Sciences 100039 BeijingChina

Plantations and production of yellowhorn,one of the most important woody oil and urban greening trees widely cultivated in northern China,have gradually become limited by drought *** epicuticular wax layer plays a key role in the protection of yellowhorn trees from drought and other ***,there is no research on the mechanism of wax loading in yellowhorn *** this study,we investigated the anatomical and physiological characteristics of leaves from different germplasm resources and different parts of the same tree and compared their cuticle *** addition,the different expression patterns of genes involved in wax accumulation were analyzed,and a coexpression network was built based on transcriptome sequencing *** and physiological comparisons found that the sun leaves from the outer part of the crown had thicker epicuticular wax,which altered the permeability and improved the drought resistance of leaves,than did shade *** on transcriptome data,a total of 3008 and 1324 differentially expressed genes(DEGs)were identified between the sun leaves and shade leaves in glossy-and non-glossy-type germplasm resources,*** identified 138 DEGs involved in wax biosynthesis and transport,including structural genes(such as LACS8,ECH1,and ns-LTP)and transcription factors(such as MYB,WRKY,and bHLH transcription factor family proteins).The coexpression network showed a strong correlation between these *** differences in gene expression patterns between G-and NG-type germplasm resources under different light conditions were very *** results not only provide a theoretical basis for screening and developing drought-resistant yellowhorn germplasm resources but also provide a data platform to reveal the wax accumulation process of yellowhorn leaves.

关键词： properties. yellow drought

Difference between focal mechanisms of Dayao earthquake doublet sequence

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Earthquake Science 2009年第6期22卷 667-673页

作者： Xiaoshan wang Xiangdong Feng Guiling Diao libing wang Lingling Cai Earthquake Administration of Hebei Province Shijiazhuang 050021 China Hongshan Benchmark Seismic Station Longyao 055350 China

Using the maximum amplitude ratios of vertical component of P and S waves recorded by a regional network, 921 focal mechanisms of Dayao earthquake doublet sequence are determined by means of synthetic seismograms of a point source of dislocation in a plane layered medium. Among them, 389 focal mechanisms are in the aftershock sequence of M6.2 earthquake occurred on 21 July, 2003 and the other 532 focal mechanisms are in the aftershock sequence of M6.1 earthquake occurred on 16 October, 2003 in Dayao, Yurman. The focal mechanism consistent parameter a of the two aftershock sequences are calculated and analyzed. According to the focal mechanism consistent parameter a, the focal mechanisms of the first aftershock sequence are more consistent than those of the second. According to the comparison of CMT solutions of the two M6 earthquakes, the physical mechanism of the doublet in the intra-plate earthquake is very complex, and many processes are involved and interacted with each other. This doublet provides insights into earthquake clustering, triggering and stress cycling.

关键词： focal mechanism consistent parameter a Dayao earthquake doublet difference

STUDY ON NEW METHOD OF IDENTIFYING GEOMETRIC ERROR PARAMETERS FOR NC MACHINE TOOLS

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Chinese Journal of Mechanical Engineering 2001年第3期14卷 198-202,206页

作者： Yun Jintian,wang Shuxin,Liu libing,Liu Youwu (College of Mechanical Engineering, Tianjin University) 天津大学机械学院天津

The methods of identifying geometric error parameters for NC machine tools are introduced. According to analyzing and comparing the different methods, a new method-displacement method with 9 lines is developed based on the theories of the movement errors of multibody system (MBS). A lot of experiments are also made to obtain 21 terms geometric error parameters by using the error identification software based on the new method.

关键词： NC machine tools Geometric error Parameter identification Multibody system

The phased chromosome-scale genome of yellowhorn sheds light on the mechanism of petal color change

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Horticultural Plant Journal 2023年第6期9卷 1193-1206页

作者： Quanxin Bi Mengke wang Jiang Li Jinmin Lian Yongchao Niu Yifan Cui Xiaojuan Liu Haiyan Yu libing wang State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijing 100091China Biozeron Shenzhen Inc.ShenzhenGuangzhouGuangdong 518000China

Yellowhorn(Xanthoceras sorbifolium), especially its varieties, is the red petal yellowhorn(X. sorbifolium var. purpurea), an important tree species with great ornamental value, and its flower petals change color throughout the flowering period. In this study, we mainly focused on the mechanism of the petal color change with transcriptomics and metabolomics data. A phased chromosome-scale assembly of the red petal yellowhorn genome was generated using the PacBio high-fidelity reads, Illumina short reads, and Phase genomics Proximo Hi-C data. The final de novo assembly yielded 533.67 Mb with a contig N50 of 5.42 Mb, and 27 501 protein-coding genes were predicted. Notably, an alternate haplotig assembly was also obtained. Furthermore, a variation database for the alleles within the genome was constructed. Subsequently, the expression pattern of flower pigmentation-related genes and allelic expression imbalance events were investigated. Apart from 6 genes involved in the anthocyanin biosynthesis pathway regulated by the activation of 15 MYB-bHLH-WD40s, the increased expression of senescencerelated gene 1(SRG1) and 2-oxoglutarate-dependent dioxygenase(DIOX5) might also result in decreasing content of lutein and increasing abundance of(E/Z)-phytoene, cyanidin-3-O-rutinoside, and cyanidin-3-O-sambubioside. These changes in genes and metabolites were most likely related to the petal color change in red petal yellowhorn. This phased chromosome-scale genome assembly provides more accurate genomic information for future molecular breeding and facilitates allele function studies of the red petal yellowhorn.

关键词： Xanthoceras sorbifolium var.purpurea Phased genome Metabolomics Transcriptomics Petal color

Sensitivity assessment of Phytophthora nicotianae to fungicides of fluazinam and its mixture with carboxylic acid amide

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烟草科技 2018年第A1期51卷 1-7页

作者： MU Wenjun LI Qi CHEN Xiuhua LI Haijiang DONG Kunle wang Jianwei ZHANG Youwu FENG Xiaohu ZHANG Zhigao wang libing SONG Jizhen Key Laboratory of Eco-environment and Leaf Tobacco Quality Zhengzhou Tobacco Research Instilule of CNTC. No.2 Fengyang Street Zhengzhou 450001China Henan Tobacco Company No. 7 Zhengqi Street Zhengzhou 450008 China Pingdingshan Branch of Henan Provincial Tobacco Company No.263 Jianshe Road Pingdingshan 467000 Henan China Luoyang Branch of Henan Provincial Tobacco Company No.246 Kaiyuan Avenue Luoyang 471026Henan China Fuzhou Branch of Jiangxi Provincial Tobacco Company No. 1666 Yingbin Avenue Fuzhou 344000 Jiangxi China

Tobacco black shank caused by Phytophthora parasitica ***(Breda de Hean)is one of the most serious diseases in tobacco growing,and few effective fungicides are available *** purpose of this study was to assess the feasibility of using fluazinam to treat tobacco black shank *** vitro toxicities of fluazinam to 62 isolates of *** were determined by mycelial growth rate *** EC50 values ranged from 0.294 6 to 2.389 9 μg/mL with a mean of 1.084 0 μg/*** sensitivity distribution was unimodal,and there was no resistant isolate in *** *** carboxylic acid amide(CAA)fungicides were single-site in action and activity to *** synergistic interactions were tested by Wadley method between fluazinam and dimethomorph,flumorph,mandipropamid,*** mixture containing dimethomoph:Huazinam at 1:2 ratio showed additive actions,with the synergy ratio of *** mixture containing flumorph and fluazinam at 1:5 ratio had the highest synergy ratio(SR 2.07).Mandipropamid and fluazinam had an additive interaction and the proportion of 2:1 had the lowest EC50 value(0.020 7 μg/mL).This study demonstrated the sensitivity of *** to fluazinam,and provided the experimental foundation to use fluazinam for tobacco black shank management.

关键词： Phytophthora nicotianae Fluazinam Dimethomorph Flumorph Mandipropamid Fungicide mixture

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“海洋中国”的人类学议题

东南学术 2024年第3期 119-128页

作者：王利兵厦门大学社会与人类学院

伴随海洋自觉意识的显现和提升,中国式现代化发展正处在逐渐超越“乡土中国”,走向“海洋中国”的新发展阶段。面对这一重大社会转型,人类学作为一门以比较性视角和整体性视角见长的学科,理应积极参与海洋中国的研究,履行人类学的公共... 详细信息

伴随海洋自觉意识的显现和提升,中国式现代化发展正处在逐渐超越“乡土中国”,走向“海洋中国”的新发展阶段。面对这一重大社会转型,人类学作为一门以比较性视角和整体性视角见长的学科,理应积极参与海洋中国的研究,履行人类学的公共责任与社会价值。从莫斯的“总体性”概念出发,海洋可以被看作一个“总体性社会事实”,围绕价值、知识、平等、政治和治理等五个议题对其展开人类学分析,其中任一人类学议题都是自然与文化交织和转化的结果。通过人类学的视角,由海洋串起的人与自然、人与人、人与社会、人与国家以及国家与国家之间的复杂关联也将更加清晰。发现和认识这些文化性与关联性,对于构建人类-海洋命运共同体和建设海洋强国具有重要意义。

关键词：海洋中国总体性社会事实人类学议题海洋治理