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2022年四川泸定MS6.8地震前视电阻率变化与区域变形的关系
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作者 解滔 李新艳 +4 位作者 韩盈 于晨 范晔 赵静 李晓帆 《地球物理学报》 北大核心 2026年第3期1140-1154,共15页
2022年9月5日四川省泸定县发生M_(S)6.8地震,震中350 km范围内运行有4个视电阻率连续观测站.2020年11月至2022年9月,三个观测站出现了中期至短期阶段不同形态的异常变化.其中,红格站为持续约22个月的下降型中期异常,甘孜站为持续约6个... 2022年9月5日四川省泸定县发生M_(S)6.8地震,震中350 km范围内运行有4个视电阻率连续观测站.2020年11月至2022年9月,三个观测站出现了中期至短期阶段不同形态的异常变化.其中,红格站为持续约22个月的下降型中期异常,甘孜站为持续约6个月的下降型中期异常,且震前3个月开始出现转折回升的短期变化特征,而冕宁站为持续约3个月的短期上升型异常.采用GNSS观测数据和断层虚位错模式分别获取了震前区域内的孕震变形积累和2017—2021年期间的面应变率场特征,泸定地震发生在面应变率场的弱变形区域.采用平面多尺度分析提取了波长约80~160 km的面应变率场分布,泸定地震震中周围呈现出四象限分布的变形特征.甘孜站位于断层虚位错模式给出的变形积累的挤压增强区域、也位于波长约80~160 km面应变率场分布的挤压区域,而冕宁和红格站位于上述两类变形结果的相对膨胀区域.甘孜站下降形态和冕宁站上升形态的异常变化与区域变形特征相符,其异常变化可能与泸定地震的晚期孕育过程存在力学机制上关联;而红格站为下降异常,与观测站所在区域的相对膨胀变形特征不相符,与泸定地震之间的关联性较弱.甘孜和冕宁站的震中距小于红格站,可能说明孕震过程对近震中区域介质因变形而诱发的电阻率变化的控制作用更强. 展开更多
关键词 泸定M_(S)6.8地震 视电阻率 异常变化 断层虚位错模式 区域变形 异常机制
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Progress in the development of self-healing polyurethane materials 被引量:1
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作者 Yongyin Zhu Henghui Deng +4 位作者 Huizhou Luo Ying Luo yu chen Zehong chen Chaoqun Zhang 《Resources Chemicals and Materials》 2025年第3期68-89,共22页
As a significant branch of smart materials,self-healing polyurethane materials mimic the biological damage repair mechanisms and have been widely applied in flexible electronics,functional coatings,biomedicine,and oth... As a significant branch of smart materials,self-healing polyurethane materials mimic the biological damage repair mechanisms and have been widely applied in flexible electronics,functional coatings,biomedicine,and other fields.This review systematically summarizes the design principles and recent advancements in both extrinsic and intrinsic self-healing polyurethane materials,highlighting their respective self-healing mechanisms and characteristics.For extrinsic system,damage repair is primarily achieved through microcapsules,hollow fibers,nanoparticles,and microvascular networks.However,their healing efficiency remains limited by the stability of carriers and the release kinetics of healing agents.In contrast,intrinsic self-healing polyurethane materials achieve self-healing through the reversibility of dynamic covalent and non-covalent bonds,which confer excellent self-healing capabilities while necessitating a precise balance between mechanical performance and self-healing efficiency.Moreover,their healing behavior is highly dependent on environmental conditions,potentially restricting their practical applications.Recent studies have demonstrated that the synergistic design of dynamic bonding networks can significantly enhance the mechanical properties,self-healing efficiency,and environmental adaptability.These developments offer new insights and theoretical foundations for designing high-performance self-healing polyurethane materials and may broaden their industrial applications. 展开更多
关键词 POLYURETHANE Extrinsic self-healing Intrinsic self-healing Dynamic bond
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预防医学专业本专科生基层就业意愿现状及相关因素分析
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作者 宋律 李珊珊 +5 位作者 高悦 杜金 虞晨 操治国 胡兴强 徐庆华 《中国农村卫生事业管理》 2026年第1期72-76,14,共6页
目的了解预防医学专业本专科生基层就业意愿现状,分析影响基层就业意愿的相关因素,为做好该专业学生培养及就业工作提供参考。方法选择安徽省内设有预防医学专业的一所本科院校和一所专科院校,对这两所学校预防医学专业本专科生,采用自... 目的了解预防医学专业本专科生基层就业意愿现状,分析影响基层就业意愿的相关因素,为做好该专业学生培养及就业工作提供参考。方法选择安徽省内设有预防医学专业的一所本科院校和一所专科院校,对这两所学校预防医学专业本专科生,采用自行设计的问卷对就业意愿及相关影响因素进行调查,利用χ^(2)检验和多因素logistic回归分析进行统计分析。结果40.43%的预防医学专业本科学生愿意去基层就业,57.42%的预防医学专业专科学生愿意去基层就业,单因素分析中,学校类型(χ^(2)=12.26,P<0.01)、是否了解就业政策(χ^(2)=6.36,P=0.012)和就业后的专业对口(χ^(2)=5.72,P=0.017)对预防医学生基层就业的意愿有影响。多因素分析中,影响预防医学专业学生基层就业意愿的因素包括学校类型(OR=1.98)、是否了解就业政策(OR=0.56)、是否专业对口(OR=2.09)及社会评价(OR=2.38)。结论安徽省预防医学专业学生基层就业意愿不高,专科院校医学专业学生基层就业意愿高于本科院校预防医学专业学生基层就业意愿。应完善就业政策,加深学生对政策理解,加大专科生培养力度,逐步填补基层预防医学专业人才短板。 展开更多
关键词 预防医学 基层医疗卫生机构 就业意愿 调查 影响因素 政策
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脲酶诱导碳酸钙沉积对3D打印类砂岩试样力学性能与微观结构的影响
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作者 田威 贾祎恒 +2 位作者 云伟 余宸 程续 《岩土力学》 北大核心 2026年第3期767-779,共13页
3D打印技术在岩石室内试验中以其快速成型、复杂结构复现等优势展现出广阔应用前景,但打印试样的力学性能较差,制约了其工程实际应用。为有效提高3D打印类砂岩试样力学性能,选用GS19型砂与呋喃树脂为基材制备的类砂岩试样为对象,采用不... 3D打印技术在岩石室内试验中以其快速成型、复杂结构复现等优势展现出广阔应用前景,但打印试样的力学性能较差,制约了其工程实际应用。为有效提高3D打印类砂岩试样力学性能,选用GS19型砂与呋喃树脂为基材制备的类砂岩试样为对象,采用不同次数脲酶诱导碳酸钙沉积(enzyme-induced calcium carbonate precipitation,简称EICP)溶液渗透处理,通过单轴压缩试验定量分析其力学性能演化规律,并采用扫描电镜结合能谱与傅里叶变换红外光谱分析从微观尺度揭示脲酶诱导碳酸钙沉积技术的力学增强机制。结果表明:试样抗压强度与弹性模量随渗透次数递增呈现增强特性,经过4次脲酶诱导碳酸钙沉积溶液渗透处理后,试样强度较对照组提升51.92%,弹性模量提升35.57%,同时其破坏模式及裂纹扩展特征与天然弱胶结砂岩相似;从微观结构研究发现,脲酶诱导碳酸钙沉积技术促使试样内部形成“树脂-碳酸钙”复合胶结相,通过增强砂粒间胶结强度,填充孔隙降低结构缺陷的双重作用机制,试样力学性能得到显著提升。研究结果拓展了3D打印技术在岩石试验领域的应用潜力。 展开更多
关键词 岩石力学 3D打印 脲酶诱导碳酸钙沉积 力学性能 微观结构
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溶剂热制备RGO/NiCo-LDHs与电化学性能分析
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作者 王静 于晨 田哲圭 《当代化工》 2026年第3期655-658,674,共5页
采用溶剂热法制备了石墨烯/镍钴氢氧化物(RGO/NiCo-LDHs)复合电极材料,借助扫描电子显微镜(SEM)、X射线衍射(XRD)分析复合材料的微观形貌与物相组成,探讨石墨烯的添加量对镍钴氢氧化物电化学性能的影响。结果表明:当RGO添加量为10 mg时... 采用溶剂热法制备了石墨烯/镍钴氢氧化物(RGO/NiCo-LDHs)复合电极材料,借助扫描电子显微镜(SEM)、X射线衍射(XRD)分析复合材料的微观形貌与物相组成,探讨石墨烯的添加量对镍钴氢氧化物电化学性能的影响。结果表明:当RGO添加量为10 mg时,电极材料性能最优,在1 A·g^(-1)电流密度下,比电容为1 100 F·g^(-1);在10 A·g^(-1)电流密度下,电容保持率为86%;在5 A·g^(-1)电流密度下,1 000次循环充放电后电容保持率为72.6%。 展开更多
关键词 溶剂热 石墨烯 镍钴氢氧化物 电化学 复合材料
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InSAR观测揭示的杂多M_(W)5.7地震地表形变及发震断层模型
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作者 郝嘉宇 宋闯 +3 位作者 能懿菡 刘振江 余琛 李振洪 《大地测量与地球动力学》 北大核心 2026年第4期435-442,共8页
利用Sentinel-1A卫星的升降轨SAR影像获取2024-03-07玉树市杂多县M_(W)5.7地震的同震形变,对发震断层几何参数和滑动分布进行反演,最后基于地震引起的库仑应力变化,分析其对周边断层的影响并对区域地震危险性进行评估。结果显示,本次地... 利用Sentinel-1A卫星的升降轨SAR影像获取2024-03-07玉树市杂多县M_(W)5.7地震的同震形变,对发震断层几何参数和滑动分布进行反演,最后基于地震引起的库仑应力变化,分析其对周边断层的影响并对区域地震危险性进行评估。结果显示,本次地震升降轨同震形变场的主形变区均呈四象限分布,升、降轨最大LOS向位移分别为3.1 cm和3.6 cm。断层反演实验表明,东北倾断层模型和西北倾断层模型均能合理地解释本次地震所引发的地表形变,但进一步综合分析同震拟合残差、区域活动断层分布及地貌特征后,更倾向于认为本次地震的发震断层是一条北西-南东走向的东北倾走滑断层。同震滑动集中在1.5~6.0 km深度,且在3.7 km深度处达到滑动峰值1.0 m。此外,计算静态库仑应力变化发现,2024年杂多地震的发生增加了雁石坪断裂区域未来发生地震的风险。 展开更多
关键词 2024年杂多M_(W)5.7地震 INSAR 同震形变 断层滑动分布 库仑应力变化
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贝伐珠单抗生物类似药与原研药治疗晚期NSCLC的临床综合评价
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作者 刘艳鑫 吕晓霖 +1 位作者 于宸 刘安昌 《药学研究》 2026年第1期96-102,共7页
目的基于真实世界数据对贝伐珠单抗生物类似药安可达和原研药安维汀治疗晚期非小细胞肺癌(NSCLC)开展临床综合评价。方法构建药品临床综合评价指标体系,基于真实世界数据,结合药品说明书信息、相关循证指南、临床研究文献等,从有效性、... 目的基于真实世界数据对贝伐珠单抗生物类似药安可达和原研药安维汀治疗晚期非小细胞肺癌(NSCLC)开展临床综合评价。方法构建药品临床综合评价指标体系,基于真实世界数据,结合药品说明书信息、相关循证指南、临床研究文献等,从有效性、安全性、经济性、可及性、创新性和适宜性6个维度,对安维汀和安可达各指标进行定性、定量整合分析。结果在有效性和安全性方面,临床试验及相关研究均表明安可达与安维汀在有效性和总体安全性上表现相似,本研究纳入的两组病例在客观缓解率(44.3%VS 39.2%)、疾病控制率(72.6%VS 82.1%)、不良反应发生率(45.3%VS 51.8%)等方面差异均无统计学意义。在经济性与可及性方面,安可达组成本-效果比优于安维汀组(2294.4元/%VS 3125.0元/%),其单位剂量价格明显更低(1126元/100 mg VS 1500元/100 mg),年度药费占居民可支配收入比例也明显更低(57.80%VS 96.25%),且在各级医疗机构中的配备结构更优。在适宜性与创新性方面,安可达在关键质量属性及临床适用性方面与安维汀高度一致,同时实现了生产工艺的深度优化和创新,二者共同推动贝伐珠单抗在国内的临床普及与深度应用。结论与安维汀相比,安可达治疗晚期NSCLC在有效性、安全性、适宜性维度具有高度相似性,在经济性和可及性维度具有明显优势,创新性互补。 展开更多
关键词 非小细胞肺癌 贝伐珠单抗 生物类似药 临床综合评价
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纵向交变磁场对电弧形态的影响
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作者 杨晨 郭春富 +3 位作者 余陈 赵运强 Volodymyr Korzhyk 刘松涛 《精密成形工程》 北大核心 2026年第3期239-250,共12页
目的揭示外加纵向交变磁场对CMT升压阶段电弧形态的影响。方法以铝合金为基板对焊接电弧进行数值模拟,对使用高速摄影机拍摄的电弧与模拟结果进行对比验证。结果施加磁场后,电弧形态从圆锥形变为钟罩形,电弧会周期性地向y轴正负半轴偏... 目的揭示外加纵向交变磁场对CMT升压阶段电弧形态的影响。方法以铝合金为基板对焊接电弧进行数值模拟,对使用高速摄影机拍摄的电弧与模拟结果进行对比验证。结果施加磁场后,电弧形态从圆锥形变为钟罩形,电弧会周期性地向y轴正负半轴偏转。电流密度与电势分布会随着电弧形态的变化而变化。电弧最高温度约为18000K,电流密度与电势最高值约为1.5×10^(8)A/m^(2)与18V。磁场会影响电弧中的电流密度与电势值,洛伦兹力会随着磁感应强度的增加而增加。施加磁场后,电弧等离子体受到洛伦兹力的影响,其运动轨迹变为螺旋形,弧长有所增加,导致电势增加。在交变磁场的作用下,带电粒子受力状态时刻发生变化,致使电弧偏转与发散。模拟的电弧形态与实验结果相吻合,电弧面积与模拟值平均相对误差为8.82%。在90Hz时,焊缝成形良好,气孔数量最小。结论在磁场的作用下,电弧形态从圆锥形变为钟罩形,带电粒子运动轨迹变为螺旋形,弧长有一定的增加,导致电势增加。在90Hz时,电弧形态稳定,焊缝成形良好,气孔较少。 展开更多
关键词 纵向交变磁场 电弧形态 电流密度 电势 洛伦兹力 焊缝成形
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Q355ND高强钢多层多道双丝埋弧焊组织及性能分析
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作者 刘松涛 郭春富 +3 位作者 余陈 杨晨 王海燕 张宇鹏 《材料热处理学报》 北大核心 2026年第1期227-236,共10页
为探究厚板多层多道焊中不同焊道组织性能的差异,采用H10Mn2焊丝和CHF101助焊剂对30 mm厚Q355ND钢进行多层多道双丝埋弧焊,对表面焊道(SWB)和根部焊道(RWB)的微观组织性能进行分析。结果表明:表面焊道与根部焊道的微观组织与力学性能存... 为探究厚板多层多道焊中不同焊道组织性能的差异,采用H10Mn2焊丝和CHF101助焊剂对30 mm厚Q355ND钢进行多层多道双丝埋弧焊,对表面焊道(SWB)和根部焊道(RWB)的微观组织性能进行分析。结果表明:表面焊道与根部焊道的微观组织与力学性能存在一定差异:表面焊道由块状铁素体、下贝氏体和少量珠光体组成,根部焊道由铁素体、贝氏体和马氏体组成;表面焊道硬度分布呈“几”形,热影响区与熔合区硬度接近,硬度最高点位于热影响区,为207.3 HV0.3,最低点位于母材,为172.6 HV0.3;根部焊道硬度分布呈M型,硬度最高点出现在靠近焊缝中心的熔合区,最高可达218.1 HV0.3,焊缝中心硬度最低为178.0 HV0.3,略高于母材;根部焊道与表面焊道拉伸试样均断裂在远离焊缝的母材部分,根部焊道平均抗拉强度为514.84 MPa,表面焊道平均抗拉强度为512.08 MPa,为脆性断裂与韧性断裂相结合的复合断裂形式,且伴有颗粒状析出物生成;根部焊缝平均冲击吸收能量172.17 J,表面焊缝平均冲击吸收能量173.33 J,冲击试样均为脆性断裂与韧性断裂的混合断裂,但表面焊道冲击断口解理面较小,韧窝更深;表面焊缝开路电位最正,钝化区间最大,且极化曲线右移,耐蚀性相对更优。 展开更多
关键词 高强钢 多层多道焊 双丝埋弧焊 焊缝组织 电化学腐蚀
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中国医学生成长指标与画像的构建及管理应用
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作者 于晨 金悦 +3 位作者 李鑫容 邵秀娟 王维民 谢阿娜 《医学与哲学》 北大核心 2026年第6期58-63,共6页
基于“中国医学生发展与培养质量调查”数据,运用I-E-P-O-T医学生发展闭环理论,引入类型学方法构建“1套通用指标+N套专业特色指标”的医学生成长评价体系,采用德尔菲专家咨询法建立成长与发展指数,通过象限交叉法将新生、在校生、应届... 基于“中国医学生发展与培养质量调查”数据,运用I-E-P-O-T医学生发展闭环理论,引入类型学方法构建“1套通用指标+N套专业特色指标”的医学生成长评价体系,采用德尔菲专家咨询法建立成长与发展指数,通过象限交叉法将新生、在校生、应届毕业生划分为四类画像,实现增值评价。该画像体系可精准识别学业规划模糊、职业能力滞后等风险群体,在13.4万份个性报告中验证其预警与干预价值,将“学得怎样”转化为可量化、预警、增值的证据链,为个体自我调控、院校精准施教、国家医教协同决策提供共通数据语言,推动医学教育从经验管理走向智能治理。 展开更多
关键词 类型学 医学生发展与成长 指标体系 学生画像 管理应用
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Thimerosal Inhibits Tumor Malignant Progression through Direct Action and Enhancing the Efficacy of PD-1-Based Immunotherapy
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作者 Ping Wang Yan-Han chen +5 位作者 Ze-Tao Zhan Jun-Xiang Zeng yu chen yuan Lin Tao chen Wei-Jie Zhou 《Oncology Research》 2026年第2期486-511,共26页
Background:Thimerosal is a mercury-containing preservative widely used in vaccines.This study aimed to investigate its potential antitumor effects and mechanisms in solid malignancies,particularly colorectal cancer(CR... Background:Thimerosal is a mercury-containing preservative widely used in vaccines.This study aimed to investigate its potential antitumor effects and mechanisms in solid malignancies,particularly colorectal cancer(CRC)and melanoma.Methods:A combination of in vitro and in vivo approaches was employed.Cell proliferation,apoptosis,migration,and invasion were assessed using Cell Counting Kit-8(CCK-8),colony formation,ATP viability,Western blotting,flow cytometry,wound-healing and Transwell assays.Subcutaneous,lung metastases,and Azoxymethane/Dextran Sulfate Sodium Salt(AOM/DSS)-induced colitis-associated CRC models were established to examine antitumor efficacy and safety.The functional role of mercury ions was validated using structural analogues.Mechanistic studies included RNA sequencing,Western blot,and immunohistochemical analysis of CD8^(+)T cell infiltration.The synergistic effect with programmed cell death protein 1(PD-1)antibody therapy was also evaluated.Results:Thimerosal potently inhibited tumor growth(with IC_(50) values ranging from 0.1 to 1μM in vitro)and significantly prolonged survival without overt toxicity in vivo.Mechanistically,mercury ions were identified as critical functional sites mediating Thimerosal’s antitumor effects.Specifically,Thimerosal inhibited the phosphorylation of Janus kinase 1(JAK1)and signal transducer and activator of transcription 3(STAT3).Furthermore,it enhanced the infiltration of CD8^(+)T cells into the tumor microenvironment and synergistically augmented the efficacy of anti-PD-1 therapy.Conclusion:Thimerosal exerts dual antitumor roles by direct JAK1/STAT3 inhibition and immune modulation via CD8^(+)T cell recruitment.It represents a promising repurposed drug and immunotherapeutic adjuvant for CRC and melanoma. 展开更多
关键词 THIMEROSAL colorectal cancer MELANOMA Janus kinase 1/signal transducer and activator of transcription 3 programmed cell death protein 1 IMMUNOTHERAPY mercury ions repurposed drug
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Conceptual design of the muonium-to-antimuonium conversion experiment(MACE)
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作者 Ai-yu Bai Han-Jie Cai +49 位作者 Chang-Lin chen Si-yuan chen Xu-Rong chen yu chen Wei-Bin cheng Ling-yun Dai Rui-Rui Fan Li Gong Zi-Hao Guo yuan He Zhi-Long Hou Yin-yuan Huang Huan Jia Hao Jiang Han-Tao Jing Xiao-Shen Kang Hai-Bo Li Jin-cheng Li Yang Li Da-Ming Liu Shu-Lin Liu Gui-Hao Lu Han Miao yun-Song Ning Jian-Wei Niu Hua-Xing Peng Alexey APetrov yuan-Shuai Qin Ming-chen Sun Jian Tang Jing-yu Tang Ye Tian Rong Wang Xiao-Dong Wang Yi Wang Zhi-Chao Wang chen Wu Tian-yu Xing Wei-Zhi Xiong yu Xu Bao-Jun Yan De-Liang Yao Tao yu Ye yuan Yi yuan Yao Zhang Yongchao Zhang Zhi-Lv Zhang Guang Zhao Shi-Han Zhao 《Nuclear Science and Techniques》 2026年第4期139-187,共49页
The spontaneous conversion of muonium to antimuonium is an interesting charged lepton flavor violation phenomenon that offers a sensitive probe for potential new physics and serves as a tool to constrain the parameter... The spontaneous conversion of muonium to antimuonium is an interesting charged lepton flavor violation phenomenon that offers a sensitive probe for potential new physics and serves as a tool to constrain the parameter space beyond the Standard Model.The Muonium-to-Antimuonium Conversion Experiment(MACE)was designed to utilize a high-intensity muon beam,a Michel electron magnetic spectrometer,a positron transport system,and a positron detection system to either discover or constrain this rare process with a conversion probability of O(10^(-13)).This article presents an overview of the theoretical framework and a detailed description of the experimental design for muonium-to-antimuonium conversion. 展开更多
关键词 MUONIUM Lepton flavor violation Muon beam Drift chamber Microchannel plate Electromagnetic calorimeter
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双钢管混凝土组合短柱轴压力学性能研究综述
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作者 李俊杰 郑帅 +3 位作者 于臣 管如意 张顺 窦绪锋 《低温建筑技术》 2026年第2期82-86,共5页
双钢管混凝土(Concrete Filled Double Steel Tube,CFDST)组合短柱凭借自重轻、刚度大、承载力高和延性好等优点,近年来在桥塔、核心筒等工程结构中得到广泛应用。文中基于国内外试验研究、数值分析及理论研究成果,系统梳理CFDST组合短... 双钢管混凝土(Concrete Filled Double Steel Tube,CFDST)组合短柱凭借自重轻、刚度大、承载力高和延性好等优点,近年来在桥塔、核心筒等工程结构中得到广泛应用。文中基于国内外试验研究、数值分析及理论研究成果,系统梳理CFDST组合短柱轴压力学性能的研究进展,归纳其常见截面形式,分析约束效应与局部屈曲特征,并对混凝土、内外钢管、截面空心率及连接件等参数对轴压承载力与结构延性的影响进行对比分析,总结现有轴压承载力计算方法及其适用范围。研究表明不同截面形式的CFDST组合短柱轴压力学性能存在显著差异,其中C-C截面整体性能较优;截面空心率与混凝土抗压强度是影响轴压承载力与结构延性的主要参数,钢管宽厚比具有重要影响,而钢管屈服强度及连接件参数的影响相对有限。工程设计中应优先控制截面空心率、混凝土抗压强度及钢管宽厚比,并进一步完善考虑连接件影响的承载力计算方法。 展开更多
关键词 双钢管混凝土 短柱轴压 截面形式 承载力计算 约束效应 局部屈曲
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Unraveling the invasion patterns of Galinsoga quadriradiata in mountain ranges:Insights from human activities,phenotypic and genetic variations
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作者 yu chen Xingjiang Song +5 位作者 Gang Liu Jia Wang Chunling Zhang Xiaojian Chang Jiabin Zou Zhihong Zhu 《Plant Diversity》 2026年第1期192-203,共12页
Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focu... Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focused on invasion patterns along elevational gradients.In this study,we asked which factors drive the global and regional distribution of the invasive plant Galinsoga quadriradiata along elevational gradients.To answer this question,we examined whether human activities(i.e.,roads)promote G.quadriradiata invasion,how seed dispersal-related traits of G.quadriradiata change along elevation gradients,and whether G.quadriradiata has adapted to high-elevation environments through phenotypic plasticity or genetic variation.On the global scale,we found that human activities and road density positively contribute to the G.quadriradiata expansion in mountainous areas.Field surveys in China revealed significant elevational differences in the seed dispersal traits of G.quadriradiata,with higher-elevation populations exhibiting lower dispersal ability and generally lower genetic diversity.Under common conditions,high-elevation populations showed higher leaf mass ratio but lower root mass ratio and reproductive allocation.This suggests that high-elevation environments create a barrier to dispersal for G.quadriradiata,and that G.quadriradiata has adapted phenotypically to these conditions.Our study indicates that the elevational invasion pattern of G.quadriradiata is shaped by multiple factors,particularly human activities and phenotypic adaptability.In addition,our finding that G.quadriradiata invasion at high elevations is not constrained by low genetic diversity indicates that monitoring and management of G.quadriradiata in mountainous areas should be strengthened. 展开更多
关键词 Invasive plants Phenotypic plasticity Seed dispersal ability Genetic variation Human activities Elevational gradient
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Lithium-Ion Dynamic Interface Engineering of Nano-Charged Composite Polymer Electrolytes for Solid-State Lithium-Metal Batteries
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作者 Shanshan Lv Jingwen Wang +7 位作者 yuanming Zhai yu chen Jiarui Yang Zhiwei Zhu Rui Peng Xuewei Fu Wei Yang yu Wang 《Nano-Micro Letters》 2026年第2期288-305,共18页
Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving... Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving the overall performance of CPEs due to their difficulty in achieving robust electrochemical and mechanical interfaces simultaneously.Here,by regulating the surface charge characteristics of halloysite nanotube(HNT),we propose a concept of lithium-ion dynamic interface(Li^(+)-DI)engineering in nano-charged CPE(NCCPE).Results show that the surface charge characteristics of HNTs fundamentally change the Li^(+)-DI,and thereof the mechanical and ion-conduction behaviors of the NCCPEs.Particularly,the HNTs with positively charged surface(HNTs+)lead to a higher Li^(+)transference number(0.86)than that of HNTs-(0.73),but a lower toughness(102.13 MJ m^(-3)for HNTs+and 159.69 MJ m^(-3)for HNTs-).Meanwhile,a strong interface compatibilization effect by Li^(+)is observed for especially the HNTs+-involved Li^(+)-DI,which improves the toughness by 2000%compared with the control.Moreover,HNTs+are more effective to weaken the Li^(+)-solvation strength and facilitate the formation of Li F-rich solid-electrolyte interphase of Li metal compared to HNTs-.The resultant Li|NCCPE|LiFePO4cell delivers a capacity of 144.9 m Ah g^(-1)after 400 cycles at 0.5 C and a capacity retention of 78.6%.This study provides deep insights into understanding the roles of surface charges of nanofillers in regulating the mechanical and electrochemical interfaces in ASSLMBs. 展开更多
关键词 Charged nanofillers Nanocomposite polymer electrolyte Dynamic lithium ion interface Solid ion-conductors Solidstate lithium-metal battery
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数据挖掘及应用课程“一体三融五化”项目式教学改革
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作者 彭琛 余波 +1 位作者 陈雨 贾宁 《计算机教育》 2026年第3期283-288,共6页
针对数据挖掘及应用课程教学中存在深入学习难、前沿技术更新滞后、工程案例缺乏等问题,基于OBE理念和PBL理论,提出“一体三融五化”项目式教学改革思路,介绍具体教学改革实践,最后说明教改成效并提出反思。
关键词 数据挖掘及应用 一体三融五化 项目式教学 OBE理念 教学改革
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Mass transfer and kinetic behavior studies on cycloaddition of carbon dioxide with propylene oxide catalyzed by ionic liquid in microchannel reactor
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作者 Yiqian Yang yu chen +4 位作者 Gang Wang Hanwen Yan Lili Wang Shuguang Xiang Chunshan Li 《Chinese Journal of Chemical Engineering》 2026年第1期187-197,共11页
The synthesis of propylene carbonate(PC)from CO_(2) and propylene oxide(PO)is a typical gas-liquid biphasic system,where gas-liquid mass transfer efficiency significantly influences CO_(2) cycloaddition reactions.Here... The synthesis of propylene carbonate(PC)from CO_(2) and propylene oxide(PO)is a typical gas-liquid biphasic system,where gas-liquid mass transfer efficiency significantly influences CO_(2) cycloaddition reactions.Here,we proposed a microchannel reaction system for the CO_(2) cycloaddition reaction catalyzed by ionic liquid within an aqueous environment.The effect of liquid flow rate,temperature and residence time on gas-liquid flow pattern,catalytic performance and mass transfer were systematically investigated.The results revealed that the PC generation rate reached 560.11 mmol·ml^(−1)·h^(−1)at a 50 cm of flow distance under reaction conditions of 105℃,2.5 MPa,QG=176 ml·min^(−1) and QL=0.3 ml·min^(−1).Variations in mass transfer rate and reaction rate at different flow distances were experimentally studied.The reaction efficiency gradually decreased with increasing flow distance,which were attributed to the reduction of mass transfer caused by decreasing bubble velocity.Optimizing bubble velocity at an appropriate position enhanced reaction efficiency by improving mass transfer,achieving a 97.7%PC yield within 2.85 min.Furthermore,a kinetic model coupling intrinsic kinetics with gas-liquid mass transfer was developed for CO_(2) cycloaddition reaction.The kinetic model was applied to predict PC reaction rates in microchannel reactors at various temperatures and liquid flow rates,achieving an average relative error of 9.6%. 展开更多
关键词 CO_(2)cycloaddition Ionic liquid Microchannel reactor Mass transfer Kinetic model
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Plasticizer Enhanced Chain Orientation and Dynamics for Printed Stretchable Conjugated Polymer Films
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作者 Fei-Yan Zhang Zhao-Min Gao +9 位作者 yu chen Jia-Yi Hua yu-Lin Han Ning-Xin Wang Ming-Hui Wang Bi-Ying Wang Guang-Tao Zhao Kui Zhao Zi-cheng Ding Yan-Chun Han 《Chinese Journal of Polymer Science》 2026年第4期959-969,I0009,共12页
The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typica... The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typically exhibit high crystallinity,limiting their mechanical deformability.Herein,we propose a plasticizer-assisted printing strategy to simultaneously enhance the stretchability and electrical performance of films based on the conjugated polymer poly(3-(5-(5-methylselenophen-2-yl)thiophen-2-yl)-6-(5-methylthiophen-2-yl)-2,5-bis(4-octyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione)(P(TDPP-Se)).The incorporation of a plasticizer trioctyl trimellitate(TOTM)promotes P(TDPP-Se)aggregation in initial solution,facilitates chain alignment under flow field,and shorten solidification process,thereby restricting randomly polymer crystallization.Consequently,a low-crystallinity film with favorable edge-on orientation,strong chain alignment and improved chain dynamics is realized,which effectively alleviates crystallites fragmentation and crack propagation under large strain.The TOTM-plasticized film exhibits approximately 2-fold improvements in fracture strain and charge mobility,along with superior mobility retention under 100%strain in comparison to the neat film.This study provides a feasible approach for microstructure control in printed stretchable conjugated polymer film. 展开更多
关键词 Stretchable conjugated polymer films Solution printing Film microstructures PLASTICIZER Charge mobility
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Shear-engineered flower-like spherulites enable record ionic conductivity of PEO-based electrolytes for solid-state lithium batteries
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作者 Xiaofei Wang Shuonan Wang +4 位作者 Zhangkuo Han Jiahan Zheng yu chen Libing Liao Hao Liu 《Chinese Chemical Letters》 2026年第2期551-558,共8页
Polyethylene oxide(PEO)-based solid polymer electrolytes(SPEs)have long faced limitations due to low ionic conductivity at ambient temperature and poor interfacial stability with lithium metal anodes.Here,we present a... Polyethylene oxide(PEO)-based solid polymer electrolytes(SPEs)have long faced limitations due to low ionic conductivity at ambient temperature and poor interfacial stability with lithium metal anodes.Here,we present a structural engineering strategy to address these challenges through shear-induced crystallization of concentrated PEO-LiTFSI solutions,which self-assemble into flower-like spherulites with radially aligned lamellar crystals.This unique structure creates continuous Li^(+)transport highways through densely packed crystalline domains,achieving a record-high ionic conductivity of 1.70×10^(-4) S/cm at 25℃ for pristine PEO-based systems.Strategic incorporation of lithium montmorillonite(MMTli,10 wt%)further optimizes the composite electrolyte,balancing high ionic conductivity(1.47×10^(-4) S/cm)with enhanced electrochemical stability(4.99 V vs.Li^(+)/Li),elevated Li^(+)transference number(0.62),and mechanical robustness.The composite electrolyte enables stable Li plating/stripping over 800 h in symmetric Li||Li cells and powers LiFePO_(4)||Li solid-state batteries with 82%capacity retention after 200 cycles at 0.2 C under ambient conditions.This work pioneers a scalable processing paradigm for crystalline polymer electrolytes,offering new insights into ion transport mechanisms and validating clay minerals as multifunctional additives for next-generation energy storage systems. 展开更多
关键词 Solid polymer electrolytes Polyethylene oxide Flower-like spherulite MONTMORILLONITE Solid-state lithium batteries
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Cactus Thorn‑Inspired Janus Nanofiber Membranes as a Water Diode for Light‑Enhanced Diabetic Wound Healing
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作者 Mei Wen Nuo yu +6 位作者 Xiaojing Zhang Wenjing Zhao Pu Qiu Wei Feng Zhigang chen yu chen Meifang Zhu 《Nano-Micro Letters》 2026年第3期757-772,共16页
Diabetic wounds present challenges in clinical management due to persistent inflammation caused by excessive exudate infiltration.Inspired by the gradient wettability of cactus thorn,this study has devised a biomimeti... Diabetic wounds present challenges in clinical management due to persistent inflammation caused by excessive exudate infiltration.Inspired by the gradient wettability of cactus thorn,this study has devised a biomimetic Janus nanofiber membrane as a water diode,which endows with gradient wettability and gradient pore size,offering sustainable unidirectional self-drainage and antibacterial properties for enhanced diabetic wound healing.The Janus membrane is fabricated by depositing a hydrophilic polyacrylonitrile/chlorin e6 layer with smaller pore sizes onto a hydrophobic poly(ε-caprolactone)with larger pore sizes,thereby generating a vertical gradient in both wettability and pore structure.The incorporation of chlorin e6 in the upper layer enables the utilization of external light energy to generate heat for evaporation and produce reactive oxygen species,achieving a high sterilization efficiency of 99%.Meanwhile,the gradient structure of the Janus membrane facilitates continuous antigravity exudate drainage at a rate of 0.95 g cm^(−2) h^(−1).This dual functionality of effective exudate drainage and sterilization significantly reduces inflammatory factors,allows the polarization of macrophages toward the M2 proliferative phenotype,enhances angiogenesis,and accelerates wound healing.Therefore,this study provides a groundbreaking bioinspired strategy for the development of advanced wound dressings tailored for diabetic wound regeneration. 展开更多
关键词 Janus membranes BIOMIMETIC Diabetic wound Self-drainage
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