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Hyperbranched Poly(α-aminonitrile)s Constructed via Catalyst-Free Multicomponent Polymerization of Trialdehydes, Diamines and Trimethylsilyl Cyanide

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CHINESE JOURNAL OF POLYMER SCIENCE 2025年第2期43卷 341-349页

作者： Cheng, Tian-Yu Ding, Jian-Qing Tong, Yu-Xin Fang, jun-guo Wang, Jia Anhui Polytech Univ Sch Chem & Environm Engn Wuhu 241000 Peoples R China Songshan Lake Mat Lab Dongguan 523808 Peoples R China

Functional hyperbranched polymers, as an important class of materials, are widely applied in diverse areas. Therefore, the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance. In this work, trialdehydes, diamines, and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions, producing hyperbranched poly(alpha-aminonitrile)s with high molecular weights (Mw up to 4.87x104) in good yields (up to 85%). The hyperbranched poly(alpha-aminonitrile)s have good solubility in commonly used organic solvents, high thermal stability as well as morphological stability. Furthermore, due to the numerous aldehyde groups in their branched chains, these hb-poly(alpha-aminonitrile)s can undergo one-pot, two-step, four-component post-polymerization with high efficiency. This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes, amines and trimethylsilyl cyanide, but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.

关键词： Catalyst-free Multicomponent polymerization Hyperbranched polymer Post-polymerization

Distributions and risk assessment of heavy metals in solid waste in lead-zinc mining areas and across the soil, water body, sediment and agricultural product ecosystem in their surrounding areas

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China Geology 2025年第1期8卷 92-106页

作者： Zhi-qiang Wu Hai-ying Li Liu-yan Lü guo-jun Liang Ting-ting Wu Jiang-xia Zhu No.117 Geological Team Bureau of Geology and Mineral Exploration and Development of Guizhou ProvinceGuiyang 550023China Ecological Environment Monitoring Center of Guizhou Province Guiyang 550023China Guizhou Institute of Geological Survey Guiyang 550081China Environmental Engineering Assessment Center of Anshun City Anshun 561000China Environmental Emergency Center of Anshun City Anshun 561000China

To identify the root causes of heavy metal contamination in soils as well as prevent and control such contamination from its sources,this study explored the accumulation patterns and ecological risks of heavy metals like Cd and Pb in solid waste in mining areas and across the water body,sediment,soil and agricultural product ecosystem surrounding the mining *** on the residual solid waste samples in lead-zinc deposits in a certain area of Guizhou Province,along with samples of topsoils,irrigation water,river sediments,and crops from surrounding *** study analyzed the distributions of eight heavy metals,i.e.,Cd,As,Cr,Hg,Pb,Zn,Cu,and Ni,in the samples through field surveys and sample ***,this study assessed the contamination levels and ecological risks of heavy metals in soils,sediments,and agricultural products using methods such as the single-factor index,Nemerow composite index,and potential ecological risk *** results indicate that heavy metals in the solid waste samples all exhibited concentrations exceeding their risk screening values,with 60%greater than their risk intervention *** soils and sediments demonstrate slight and moderate comprehensive ecological risks of heavy *** single-factor potential ecological risks of heavy metals in both the soil and sediment samples decreased in the order of Hg,Cd,Pb,As,Cu,Zn,Cr,and Ni,suggesting the same sources of heavy metals in the soils and *** of the agricultural product samples exhibited over-limit concentrations of heavy metals dominated by Cd,Pb,Ni,and Cr,excluding Hg and *** agricultural product assessment using the Nemerow composite index reveals that 35%of the agricultural product samples reached the heavy metal contamination level,implying that the agricultural products from farmland around the solid waste dumps have been contaminated with heavy *** eight heavy metals in the soil,sediment,and agricultural product samples manifested hig

关键词： Lead-zinc mining area Solid waste Soil Water body Sediment Agricultural product Nemerow composite index Cd,Pb,Ni,Cr elements Heavy metal contamination Ecological risk assessment Coefficients of variation(CVs) Environmental restoration engineering

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郭军基于“肾-精室”辨治阳痿经验

北京中医药 2025年第1期44卷 84-87页

作者：王浩常洪源吕珲王安民郭军王福中国中医科学院西苑医院男科北京100091

阳痿是较为常见的男性性功能障碍疾病,其病因病机复杂,多表现为复合证型,常以肾虚为主,湿、热、瘀、郁等实邪为标。郭军教授将“肾精亏虚,精室失用”作为阳痿发生的核心病机,认为本病本虚在肾,邪实在精室,精室失用是本病发生的重要环节... 详细信息

阳痿是较为常见的男性性功能障碍疾病,其病因病机复杂,多表现为复合证型,常以肾虚为主,湿、热、瘀、郁等实邪为标。郭军教授将“肾精亏虚,精室失用”作为阳痿发生的核心病机,认为本病本虚在肾,邪实在精室,精室失用是本病发生的重要环节;并在此基础上,拟定了“补肾”“通利精室”的原则,从补肾祛湿、补肾泻热、补肾活血和补肾解郁立法,恢复男性勃起功能。

关键词：阳痿肾-精室肾虚精亏精室失用

直写成型金属微粒悬浮液流变特性及动力粘度研究

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塑性工程学报 2025年第1期32卷 209-217页

作者：郭恒锐郭俊卿陈拂晓皇涛相楠河南科技大学材料科学与工程学院河南洛阳471023 有色金属新材料与先进加工技术省部共建协同创新中心河南洛阳471023

为制备出符合直写成型技术要求的金属微粒悬浮液,对金属微粒悬浮液的流变特性及动力粘度进行了研究。制备了具有不同动力粘度的金属微粒悬浮液,在室温下进行了动力粘度测试,依据内摩擦力理论对其流变特性及动力粘度进行了研究,分析了微... 详细信息

为制备出符合直写成型技术要求的金属微粒悬浮液,对金属微粒悬浮液的流变特性及动力粘度进行了研究。制备了具有不同动力粘度的金属微粒悬浮液,在室温下进行了动力粘度测试,依据内摩擦力理论对其流变特性及动力粘度进行了研究,分析了微粒体积分数及粒径对其流变特性及动力粘度的影响。结果表明,PVA溶液作为液相的金属微粒悬浮液具有直写成型技术要求的流变特性;调节微粒体积分数及粒径可以调控金属微粒悬浮液的动力粘度;通过Williamson模型及牛顿插值法量化了微粒体积分数与动力粘度之间的关系,提供了预测悬浮液动力粘度的方法。

关键词：直写成型金属微粒悬浮液内摩擦力流变特性 Williamson模型

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基于雷电分形模型的架空线路绕击特性分析试验

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电力工程技术 2025年第1期44卷 126-135页

作者：占金涛杨天翼郭俊西安交通大学电气工程学院陕西西安710049

近年来,一类在电气几何模型、先导发展模型等基础上提出的可以体现雷电曲折性和分散性的分形模型逐步被用于架空线路雷电屏蔽性能研究。文中基于模拟试验和自然雷电的等效性,搭建1∶40缩比试验平台,以常见500 kV输电线路用ZB6T型杆塔为... 详细信息

近年来,一类在电气几何模型、先导发展模型等基础上提出的可以体现雷电曲折性和分散性的分形模型逐步被用于架空线路雷电屏蔽性能研究。文中基于模拟试验和自然雷电的等效性,搭建1∶40缩比试验平台,以常见500 kV输电线路用ZB6T型杆塔为研究对象,施加160/2 500μs负极性操作冲击波,分别研究绕击率与空间分布和保护角的关系。基于WZ模型和有限差分法建立雷电分形模型,在缩比试验间隙配置下进行线路绕击特性仿真分析。模拟试验和仿真结果均表明:输电线绕击率高的点集中在靠近传输线处,绕击空间整体呈现倒抛物线型,符合绕击规律。保护角减小,则绕击率相应降低,同时绕击空间略有减小。仿真结果与试验数据对比表明,文中构建的雷电分形模型在线路绕击率预测上具有较高可靠性。

关键词：雷电分形模型等效性缩比试验架空线路绕击率雷电屏蔽分析

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试析建筑外墙外保温系统防火安全技术

工程建设与设计 2025年第3期 47-49页

作者：郭峻青如东县消防救援大队江苏南通226400

通过调查不同类型建筑的外墙外保温系统防火技术要求,并于防火安全技术方面详细论述聚苯乙烯泡沫塑料板薄抹灰系统、胶粉聚苯颗粒保温浆料系统、机械固定钢丝网架聚苯乙烯泡沫塑料板系统、岩棉板系统等技术。研究结果显示,不同技术在防... 详细信息

通过调查不同类型建筑的外墙外保温系统防火技术要求,并于防火安全技术方面详细论述聚苯乙烯泡沫塑料板薄抹灰系统、胶粉聚苯颗粒保温浆料系统、机械固定钢丝网架聚苯乙烯泡沫塑料板系统、岩棉板系统等技术。研究结果显示,不同技术在防火性能、施工难度和成本方面存在差异。对此提出了一系列建筑外墙外保温系统防火安全对策,诸如改进设计标准、加强施工现场管理等。

关键词：建筑外墙外保温系统防火安全技术防火对策

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逐级递进式高耗能抗撞磁流变阻尼器设计

科学技术与工程 2025年第5期25卷 1896-1903页

作者：孟壮于国军何骏叶晓龙高飞江苏大学土木工程与力学学院镇江212013

为了更好地保护桥墩与船舶安全,针对桥墩防撞装置多为被动式耗能,其动态响应及防撞耗能效果较差,装置适应性有限等问题设计了一种适用于桥墩的逐级递进式高耗能抗撞磁流变阻尼器。通过建立力学模型确立了阻尼器结构参数;使用有限元对结... 详细信息

为了更好地保护桥墩与船舶安全,针对桥墩防撞装置多为被动式耗能,其动态响应及防撞耗能效果较差,装置适应性有限等问题设计了一种适用于桥墩的逐级递进式高耗能抗撞磁流变阻尼器。通过建立力学模型确立了阻尼器结构参数;使用有限元对结构强度及磁路进行分析。结果表明:结构部件强度满足要求,2 A电流下间隙处磁感应强度可达到1.2 T;缸筒内设置3个活塞,在不同的撞深位移下可协同工作,将阻尼器的耗能分成3个阶段,无电流下最小阻尼力为15 kN,最大阻尼力为496 kN,阻尼力随着位移的变大增加了481 kN;2.5 A电流下阻尼力随位移从78 kN增大到1204 kN,提升了约15倍。有效提高了阻尼器的出力且实现分级递进式抗冲耗能的优良效果;在桥墩防撞装置中应用可实现半主动式防撞耗能。理论与有限元仿真结果基本吻合,证明了阻尼器设计的合理性。

关键词：逐级递进抗撞耗能磁流变阻尼器结构设计有限元分析

Modified Moving Particle Semi-Implicit Meshless Method for Incompressible Fluids

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Journal of Thermal Science 2004年第3期13卷 226-234页

作者： jun guo Zhi Tao Beijing Univ Aeronaut & Astronaut Div 402 Dept Jet Prop Beijing 100083 Peoples R China

A modified moving particle semi-implicit method (MPS) is presented for incompressible fluids. Modification is on the removal of imaginary nodes to enforce the boundary conditions. Comparison with the original imaginary-node scheme has proved the validity of the proposed method. Performance of MPS method in general is also investigated by comparing the results of Lid-driven and natural convection problems with finite volume method (FVM). It is found that MPS method shows relatively strong numerical diffusion, and for convection problems, MPS method appears to be less robust than FVM. Though better results could be obtained with different kernel functions, such improvement is quite limited.

关键词： meshless method incompressible fluids numerical diffusion kernel function.

Geosynthetics used to stabilize vegetated surfaces for environmental sustainability in civil engineering

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Frontiers of Structural and Civil Engineering 2017年第1期11卷 56-65页

作者： Jie HAN jun guo Department of Civil Environmental and Architectural Engineering the University of Kansas Lawrence KS 66044 USA

Geosynthetics, factory-manufactured polymer materials, have been successfully used to solve many geotechnical problems in civil engineering. Two common applications are earth stabilization and erosion control. Geosynthetics used for earth stabilization include but are not limited to stabilized slopes, walls, embankments, and roads. Geosynthetics used for erosion control are mostly related to slopes, river channels and banks, and pond spillways. To enhance environmental sustainability, vegetation has been increasingly planted on the facing or surfaces of these earth structures. Under such a condition, geosynthetics mainly function as surficial soil stabilization while vegetation provides green appearance and erosion protection of earth surfaces. Recently, geosynthetic or geosynthetic-like material has been used to form green walls outside or inside buildings to enhance sustainability. Geosynthetics and vegetation are often integrated to provide combined benefits. The interaction between geosynthetics and vegetation is important for the sustainability of the earth and building wall surfaces. This paper provides a review of the current practice and research in the geosynthetic stabilization of vegetated earth and building surfaces for environmental sustainability in civil engineering with the emphases on geosynthetic used for erosion protection, geosynthetic-stabilized slopes, geosynthetic-stabilized unpaved shoulders and parking lots, and geosynthetic-stabilized vegetated building surfaces.

关键词： erosion geosynthetic stabilization sustainability vegetation