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Toward a non-invasive cleaning of the wall painting using polyelectrolyte hydrogel

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Science China(Technological Sciences) 2023年第8期66卷 2213-2224页

作者： LI Qiang WU Chao peng yajun ZHANG BingJian School of Art and Archaeology Zhejiang UniversityHangzhou 310028China Zhejiang University Press Hangzhou 310028China Zhejiang Museum of Natural History Hangzhou 310000China Department of Chemistry Zhejiang UniversityHangzhou 310027China

Developing advanced cleaning systems for the removal of unwanted layers from painted surfaces is still a challenging issue that needs to be addressed in the field of cultural *** this work,we proposed the use of novel polyelectrolyte hydrogels prepared via free radical polymerization and freeze-thaw *** sulfobetaine methacrylate(SBMA)was crosslinked with methylacryloyloxyethyl trimethylammonium(DMC)through covalent bonding to yield zwitterionic polyelectrolyte poly(SBMA-co-DMC)(PSD).Introducing PSD into the polyvinyl alcohol/carboxymethyl chitosan(PVA/CMC)hydrogel network enhanced the intermolecular electrostatic interactions and changed the porous structure and swelling behaviors,thus leading to improved mechanical *** adsorption ability of the PVA/CMC/PSD polyelectrolyte hydrogels toward dyes(rhodamine B and congo red)and metal ions(Cu^(2+)and K^(+))varied with increasing amounts of PSD,which could be attributed to cationic PSD tuning the net charges in the *** cleaning effectiveness of the PVA/CMC/PSD polyelectrolyte hydrogels was assessed on wall painting mock-ups coated with soil,red paint,and soluble salts,using microscopic and spectroscopic *** results showed that the hydrogel adhered to rough surfaces and removed unwanted substances effectively without leaving determinable residues,providing a possible safe and efficient method for the cleaning of important artifacts.

关键词： polyelectrolyte hydrogel SBMA adsorption cleaning effectiveness

Analyzing biases of nitrogen contents and δ^(15)N values arising from acidified marine sediments with different CaCO_3 concentrations

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Acta Oceanologica Sinica 2018年第8期37卷 1-5页

作者： peng yajun LIU Dongyan WANG Yujue RICHARD Pierre KEESING John K. Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences School of Management Science Guizhou University of Finance and Economics State Key Laboratory of Estuarine and Coastal Research East China Normal University Littoral Environment et Sociétés UMR 7266 CNRS-Université de La Rochelle CSIRO Oceans and Atmosphere and University of Western Australia Oceans Institute Indian Ocean Marine Research Centre

In some studies, the researchers pretreated and measured organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） of marine sediment together, to save costs and resources of analysis. However, the procedure of acidification to remove inorganic carbon for analysing δ^（13）C can affect the values of nitrogen and δ^（15）N, and the biases vary a lot depending on the CaCO_3 contents of sediments. In this study, the biases of total nitrogen（TN）and δ^（15）N values arising from acidified sediments were compared between the CaCO_3-poor（1%–16%） and CaCO_3-rich（20%–40%） samples. TN and δ^（15）N values were altered during acid treatment（without centrifugation） that possibly led to N-containing compounds volatilization. For CaCO_3-poor samples, acidification led to a range of 0%–40% TN losses and 0‰–2‰ shift in δ^（15）N values; and 10%–60% TN losses and 1‰–14‰ shift in δ^（15）N values for CaCO_3-rich samples. The biases from most samples exceeded the precision of the instrument（0.002% for TN and 0.08‰ for δ^（15）N）, and high biases could mislead our judgment for the environmental implication of the data. Thus,avoiding co-analysis of organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） in sediments, even for CaCO_3-poor marine sediments, is necessary.

关键词： stable isotope nitrogen nitrogen CaCO3 acidification marine sediment

Weed biology andmanagement in the multi-omics era:Progress and perspectives

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Plant Communications 2024年第4期5卷 16-35页

作者： Ke Chen Haona Yang Di Wu yajun peng Lei Lian Lianyang Bai Lifeng Wang Key Laboratory of Indica Rice Genetics and Breeding in the Middle and Lower Reaches of Yangtze River Valley Ministry of Agriculture and Rural AffairsHunan Rice Research InstituteHunan Academy of Agricultural SciencesChangsha 410125China State Key Laboratory of Hybrid Rice Hunan Academy of Agricultural SciencesChangsha 410125China Longping Branch College of BiologyHunan UniversityChangsha 410125China Huangpu Research Institute of Longping Agricultural Science and Technology Guangzhou 510715China Hunan Weed Science Key Laboratory Hunan Agricultural Biotechnology Research InstituteHunan Academy of Agricultural SciencesChangsha 410125China Qingdao Kingagroot Compounds Co.Ltd Qingdao 266000China

Weeds pose a significant threat to crop production,resulting in substantial yield *** addition,they possess robust weedy traits that enable them to survive in extreme environments and evade human *** recent years,the application of multi-omics biotechnologies has helped to reveal the molecular mechanisms underlying these weedy *** this review,we systematically describe diverse applications of multi-omics platforms for characterizing key aspects of weed biology,including the origins of weed spe-cies,weed classification,and the underlying genetic and molecular bases of important weedy traits such as crop–weed interactions,adaptability to different environments,photoperiodicflowering responses,and herbicide *** addition,we discuss limitations to the application of multi-omics techniques in weed science,particularly compared with their extensive use in model plants and *** this regard,we provide a forward-looking perspective on the future application of multi-omics technologies to weed science *** powerful tools hold great promise for comprehensively and efficiently unraveling the intricate molecular genetic mechanisms that underlie weedy *** resulting advances will facilitate the development of sustainable and highly effective weed management strategies,promoting greener practices in agriculture.

关键词： weeds multi-omics weed management genomics RNA-seq

Genomic insights into the origin, adaptive evolution, and herbicide resistance of Leptochloa chinensis, a devastating tetraploid weedy grass in rice fields

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Molecular Plant 2022年第6期15卷 1045-1058页

作者： Lifeng Wang Xuepeng Sun yajun peng Ke Chen Shan Wu Yanan Guo Jingyuan Zhang Haona Yang Tao Jin Lamei Wu Xiaomao Zhou Bin Liang Zhenghong Zhao Ducai Liu Zhangjun Fei Lianyang Bai State Key Laboratory of Hybrid Rice Hunan Academy of Agricultural SciencesChangsha 410125China Hunan Weed Science Key Laboratory Hunan Academy of Agricultural SciencesChangsha 410125China Boyce Thompson Institute Cornell UniversityIthacaNY 14853USA College of Horticulture Science Zhejiang A&F UniversityHangzhou 311300China Qingdao Kingagroot Compounds Co.Ltd Qingdao 266000China USDA-ARS Robert W.Holley Center for Agriculture and HealthIthacaNY 14853USA

Chinese sprangletop (Leptochloa chinensis), belonging to the grass subfamily Chloridoideae, is one of the most notorious weeds in rice ecosystems. Here, we report a chromosome-scale reference genome assembly and a genomic variation map of the tetraploid L. chinensis. The L. chinensis genome is derived from two diploid progenitors that diverged ∼10.9 million years ago, and its two subgenomes display neither fractionation bias nor overall gene expression dominance. Comparative genomic analyses reveal substantial genome rearrangements in L. chinensis after its divergence from the common ancestor of Chloridoideae and, together with transcriptome profiling, demonstrate the important contribution of tetraploidization to the gene sources for the herbicide resistance of L. chinensis. Population genomic analyses of 89 accessions from China reveal that L. chinensis accessions collected from southern/southwestern provinces have substantially higher nucleotide diversity than those from the middle and lower reaches of the Yangtze River, suggesting that L. chinensis spread in China from the southern/southwestern provinces to the middle and lower reaches of the Yangtze River. During this spread, L. chinensis developed significantly increased herbicide resistance, accompanied by the selection of numerous genes involved in herbicide resistance. Taken together, our study generated valuable genomic resources for future fundamental research and agricultural management of L. chinensis, and provides significant new insights into the herbicide resistance as well as the origin and adaptive evolution of L. chinensis.

关键词： Leptochloa weed sgenome polyploidization genome evolution genetic diversity adaptive selection herbicide resistance

Resistance of Barnyard Grass(Echinochloa crusglli) to Quinclorac in Double-harvest Rice Area in Hunan Province of China

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Plant Diseases and Pests 2013年第5期4卷 23-25,37页

作者： Ma Guolan Liu Ducai Liu Xueyuan Tang Tao peng yajun Hunan Plant Protection Research Institute

[ Objective] The paper was to study the resistance of barnyard grass to quinclorac in double-harvest rice area in Hunan Province of China. [ Method ] Using whole-plant determination method, the resistance of 36 biotypes of barnyard grass to quinclorac in double-harvest rice area in Hunan Province was studied. [ Result ] The biotype collected from Lijiaping Town of Shaoyang County was the most susceptible barnyard grass to quinclerac, and the EC50 value was 70. 253 1 g a. i./hm2 , so it was recognized as the sensitive biotype. The biotypes collected from Caowei Town of Yuanjiang County （ HN3 and HN4 from direct seeding rice fields） and Zhongyukou Town of Nanxian County presented very high resistance to quinclorac ; the ECho values were 1 999. 122 5, 1 664.544 6 and 1 022.739 5 g a. i./hm2, and their resistance indexes reached 28.46, 23.69 and 14.56, respectively, indicating that these throe biotypes hod high level of resistance to quinclo- rac. EC50 values of about 22 biotypes were ranged from 144. 837 3 to 408.289 4 g a. i./hm2, and resistance indexes were ranged from 2.06 to 5.81, indicating that these biotypes hod produced resistance to quinclorac. EC50 values of other 10 biotypes were ranged from 98.032 6 to 138. 660 9 g a. i./hm2, and the resistance in- dexes were ranged from 1.40 to 1.97, indicating that the sensitivity of barnyard grass in these places was decreasing. [ Conclusion] The paper provided guidance for scientific and rational use of quinclorac in paddy fields.

关键词： Barnyard grass Quinclorac Resistance

中国东北地区与俄罗斯远东地区农业合作影响因素分析——基于层次分析法

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黑龙江畜牧兽医（下半月） 2017年第6期 5-11页

作者：彭亚骏崔宁波东北农业大学经济管理学院哈尔滨150030

中国东北地区与俄罗斯远东地区的农业合作是振兴东北老工业基地、实现远东地区大开发的关键内容,能够促进两地区乃至两个国家的农业进步和经济发展。笔者采用层次分析法,建立政府监管、人才科技、社会文化、经济利益、合作主体五个层面... 详细信息

中国东北地区与俄罗斯远东地区的农业合作是振兴东北老工业基地、实现远东地区大开发的关键内容,能够促进两地区乃至两个国家的农业进步和经济发展。笔者采用层次分析法,建立政府监管、人才科技、社会文化、经济利益、合作主体五个层面的15个评价指标体系,分析其对农业合作的影响程度。最后根据模型结果,从加强政府作用,经济利益诱导,以市场需求为导向等方面提出两地区农业合作的对策建议。

关键词：一带一路中国东北地区俄罗斯远东地区农业合作影响因素层次分析法

氩激光超全视网膜光凝术治疗新生血管性青光眼

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第二军医大学学报 1999年第5期20卷 319-321页

作者：彭亚军韩丽荣第二军医大学长海医院眼科

目的：评估氩激光超全视网膜光凝术对视网膜中央静脉阻塞所致的新生血管性青光眼的疗效。方法：用氩蓝绿激光对１２眼视网膜中央静脉阻塞所致的新生血管性青光眼行超全视网膜光凝术，每眼平均光凝点达２０５０点。结果：术后８例虹膜和... 详细信息

目的：评估氩激光超全视网膜光凝术对视网膜中央静脉阻塞所致的新生血管性青光眼的疗效。方法：用氩蓝绿激光对１２眼视网膜中央静脉阻塞所致的新生血管性青光眼行超全视网膜光凝术，每眼平均光凝点达２０５０点。结果：术后８例虹膜和前房角新生血管全部萎缩，４例术后眼压控制至正常水平，８例术后眼压仍高，但较术前明显下降，虽需药物或其他手术辅助降压，但全部患者的眼痛、头痛症状均有减轻或消失。结论：超全视网膜光凝术应为视网膜中央静脉阻塞所致的新生血管性青光眼的首选治疗方法，光凝越早，范围越广，效果越好。

关键词：青光眼新生血管性激光光凝术氩激光

“扫一扫”,让方志资源“飞入寻常百姓家”——涟水县“掌上方志馆”发展报告

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江苏地方志 2020年第2期 75-78页

作者：彭亚君涟水县地方志办公室江苏淮安223400

涟水县“掌上方志馆”是江苏省2019年度地方志工作创新项目之一。近年,由于网络技术、数码存储与传输技术等电子信息技术的全面普及与发展,人们的阅读方式发生了巨大变化,涟水县地方志办公室由此探索了移动化、便捷化、地域化的数字方... 详细信息

涟水县“掌上方志馆”是江苏省2019年度地方志工作创新项目之一。近年,由于网络技术、数码存储与传输技术等电子信息技术的全面普及与发展,人们的阅读方式发生了巨大变化,涟水县地方志办公室由此探索了移动化、便捷化、地域化的数字方志工作。在保留纸质书籍内容与特色的基础上,通过智能化手段,创新展陈方式,把地情资料融入“掌中”,将书籍与虚拟翻阅、音频、视频相结合,以数字化和信息化的方式弥补了实体方志馆承载量有限、纸质书籍携带翻阅不便等问题,打造现代化阅读新体验,推动方志资源利用“活起来”“立起来”“动起来”。

关键词：方志馆手机阅读掌上方志馆涟水县报告

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高强2024铝合金的固溶时效行为研究

铸造技术 2017年第3期38卷 581-584页

作者：彭焕伟孙亚军吉林省经济管理干部学院机电工程学院吉林长春130012 一汽解放发动机分公司产品工程部吉林长春130000

对2024合金薄板进行了固溶和时效热处理,研究了时效时间对合金硬度、电导率、力学性能、组织和断口形貌的影响。结果表明,经过固溶和时效处理后,2024合金组织主要由α-Al、Al_7Cu_2Fe和Al_2CuMg相组成。随着时效时间增加,显微硬度先增... 详细信息

对2024合金薄板进行了固溶和时效热处理,研究了时效时间对合金硬度、电导率、力学性能、组织和断口形貌的影响。结果表明,经过固溶和时效处理后,2024合金组织主要由α-Al、Al_7Cu_2Fe和Al_2CuMg相组成。随着时效时间增加,显微硬度先增大后降低,在24h时显微硬度最大。电导率随时效时间延长而提高,时效12~24 h时,电导率增加速度较快,超过24 h后的增加速度变缓。经过490℃×1h固溶+175℃×24 h时效处理后,2024合金可以取得最佳的强度和塑性结合。

关键词： 2024铝合金固溶时效力学性能电导率