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Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility
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作者 chen li Leilei liang +2 位作者 Baoshan Zhang Yi Yang Guangbin Ji 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期401-416,共16页
Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR clo... Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration limitations.Here,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption layer.The top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass through.Meanwhile,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric synergy.Through theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ranges.Specifically,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of 0.35.Additionally,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments. 展开更多
关键词 Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy MULTIFUNCTION
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病态加权最小二乘混合模型的k-Liu估计解法
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作者 陈丽 王岩 邵德盛 《统计与决策》 CSSCI 北大核心 2024年第8期17-21,共5页
文章综合加权多源观测模型及最小二乘混合模型,组合两种有偏估计算法得到组合有偏估计算法。利用岭估计与Liu估计形成一种新的有偏估计——k-Liu估计,其可以抵抗法方程系数矩阵的病态性,同时可以有效降低参数估值的均方误差。通过构建... 文章综合加权多源观测模型及最小二乘混合模型,组合两种有偏估计算法得到组合有偏估计算法。利用岭估计与Liu估计形成一种新的有偏估计——k-Liu估计,其可以抵抗法方程系数矩阵的病态性,同时可以有效降低参数估值的均方误差。通过构建目标函数导出k-Liu估计在病态最小二乘混合模型中参数的通用解式、均方误差式和协因数的计算式,推导出k-Liu估计中修正因子的计算式,通过广义交叉检核法确定岭参数。最后,通过多种估计法参与算例解算,得出k-Liu估计可以进一步提升混合最小二乘模型的解算精度。 展开更多
关键词 病态性 最小二乘混合模型 岭估计 k-Liu估计 广义交叉检核法
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An intrinsically self-healing and anti-freezing molecular chains induced polyacrylamide-based hydrogel electrolytes for zinc manganese dioxide batteries 被引量:1
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作者 Haiyang liao Wenzhao Zhong +8 位作者 chen li Jieling Han Xiao Sun Xinhui Xia Ting li Abolhassan Noori Mir F.Mousavi Xin liu Yongqi Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期565-578,I0013,共15页
The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self... The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self-healing for meeting the rapid development of flexible and wearable devices in diverse service conditions.Herein,we design a new hydrogel electrolyte(AF/SH-Hydrogel)with intrinsic anti-freezing/self-healing capabilities by introducing ethylene glycol molecules,dynamic chemical bonding(disulfide bond),and supramolecular interaction(multi-hydrogen bond)into the polyacrylamide molecular chain.Thanks to the exceptional freeze resistance(84%capacity retention at-20℃)and intrinsic self-healing capabilities(95%capacity retention after 5 cutting/self-healing cycles),the obtained AF/SH-Hydrogel makes the zinc||manganese dioxide cell an economically feasible battery for the state-of-the-art applications.The Zn||AF/SH-Hydrogel||MnO_(2)device offers a near-theoretical specific capacity of 285 m A h g^(-1)at 0.1 A g^(-1)(Coulombic efficiency≈100%),as well as good self-healing capability and mechanical flexibility in an ice bath.This work provides insight that can be utilized to develop multifunctional hydrogel electrolytes for application in next generation of self-healable and freeze-resistance smart aqueous energy storage devices. 展开更多
关键词 Flexible aqueous battery Hydrogel electrolyte ANTI-FREEZING SELF-HEALING Dual-dynamic reversible bond
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Atomically dispersed Ni electrocatalyst for superior urea-assisted water splitting 被引量:1
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作者 Fang Luo Shuyuan Pan +3 位作者 Yuhua Xie chen li Yingjie Yu Zehui Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期1-6,I0002,共7页
Urea oxidation reaction(UOR) has been selected as substitution for oxygen evolution reaction ascribing to its low thermodynamic voltage as well as utilization of nickel as electrocatalyst.Herein,we report the formatio... Urea oxidation reaction(UOR) has been selected as substitution for oxygen evolution reaction ascribing to its low thermodynamic voltage as well as utilization of nickel as electrocatalyst.Herein,we report the formation of nickel single atoms(Ni-SAs) as exceptional bifunctional electrocatalyst toward UOR and hydrogen evolution reaction(HER) in urea-assisted water splitting.In UOR catalysis,Ni-SAs perform a superior catalytic performance than Ni-NP/NC and Pt/C ascribing to the formation of HOO-Ni-N_(4) structure evidenced by in-situ Raman spectroscopy,corresponding to a boosted mass activity by 175-fold at 1.4 V vs.RHE than Ni-NP/NC.Furthermore,Ni-SAs requires only 450 mV overpotential to obtain HER current density of 500 mA cm^(-2).136 mA cm^(-2) is achieved in urea-assisted water splitting at1.7 V for Ni-SAs,boosted by 5.7 times than Pt/C-IrO_(2) driven water splitting. 展开更多
关键词 Urea oxidation reaction Hydrogen evolution reaction Nickel single atoms Water splitting
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血清Ghrelin、VEGF-A水平对妊娠期糖尿病患者早发型胎儿生长受限的预测价值 被引量:1
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作者 陈丽 卢国萍 刘芙蓉 《新疆医科大学学报》 CAS 2024年第5期699-703,共5页
目的探讨血清生长激素释放多肽(Ghrelin)、血管内皮生长因子-A(Vascular endothelial growth factor-A,VEGF-A)水平对妊娠期糖尿病(Gestational diabetes mellitus,GDM)患者早发型胎儿生长受限(Fetal growth restriction,FGR)的预测价... 目的探讨血清生长激素释放多肽(Ghrelin)、血管内皮生长因子-A(Vascular endothelial growth factor-A,VEGF-A)水平对妊娠期糖尿病(Gestational diabetes mellitus,GDM)患者早发型胎儿生长受限(Fetal growth restriction,FGR)的预测价值。方法选取2020年3月至2022年3月在海南省妇女儿童医学中心进行产前检查并分娩的GDM患者为研究对象,根据胎儿体重分为FGR组(n=26)、正常组(n=82)和巨大儿组(n=18)。比较3组血清Ghrelin、VEGF-A水平,并采用Pearson相关系数法分析两指标与胎儿体重的相关性,并绘制受试者工作特征(Receiver operating characteristic curve,ROC)曲线分析血清Ghrelin、VEGF-A对GDM孕妇发生早发型FGR的预测价值。结果131例GDM孕妇不良妊娠结局总发生率为37.40%(49/131),其中巨大儿18例、FGR 26例。正常组空腹血糖水平、剖宫产占比均低于FGR组、巨大儿组,FGR组与巨大儿组空腹血糖水平、剖宫产占比比较,差异无统计学意义(P>0.05)。与巨大儿组相比,FGR组和正常组孕妇血清Ghrelin水平偏高,且FGR组高于正常组,而FGR组和正常组VEGF-A水平偏低,且FGR组VEGF-A水平低于正常组(P<0.05)。Pearson相关性分析显示,血清Ghrelin与胎儿出生体重呈负相关(r=-0.677,P<0.05),VEGF-A与胎儿出生体重呈正相关(r=0.690,P<0.05)。ROC曲线显示,血清Ghrelin、VEGF-A单独预测GDM孕妇发生早发型FGR的曲线下面积(Area under curve,AUC)分别为0.672、0.755,联合预测AUC为0.848,联合预测效能较单独预测效能更好(P<0.05)。结论GMD孕妇体内血清Ghrelin、VEGF-A水平与胎儿体重具有相关性,是早发型FGR的预测标志物,且两者联合预测GMD孕妇早发型FGR临床价值更高。 展开更多
关键词 妊娠期糖尿病 早发型胎儿生长受限 生长激素释放多肽 血管内皮生长因子-A
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链霉菌Streptomyces sp.FIM18-327次级代谢产物的研究
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作者 陈丽 谢立君 +5 位作者 周剑 林如 温耀明 邱观荣 江红 江宏磊 《中国抗生素杂志》 北大核心 2025年第1期33-40,共8页
目的本文对链霉菌Streptomyces sp.FIM18-327发酵液中的次级代谢产物进行研究。方法采用浸提、萃取、硅胶柱层析及制备HPLC等方法分离纯化次级代谢产物,其结构经MS、NMR波谱数据分析并与文献对比来确定。结果从该菌株发酵液中分离纯化得... 目的本文对链霉菌Streptomyces sp.FIM18-327发酵液中的次级代谢产物进行研究。方法采用浸提、萃取、硅胶柱层析及制备HPLC等方法分离纯化次级代谢产物,其结构经MS、NMR波谱数据分析并与文献对比来确定。结果从该菌株发酵液中分离纯化得到6个化合物,均为吲哚并咔唑类生物碱,其结构分别鉴定为7-ethyl-UCN-01(1)、RK-1409(2)、RK-286C(3)、星孢菌素(4)、7-methoxy-RK-286C(5)、K252c(6)。结论化合物1~6均是首次从该菌株中分离获得,其中化合物1是新的天然产物,活性结果表明化合物1~3对人源乳腺癌细胞MCF-7和胃癌细胞NCI-N87的抑制活性较好,其IC_(50)值为0.14~2.29μmol/L;同时也发现它们对激酶PKCθ也具有很强的抑制活性,其IC_(50)值为IC_(50)值为0.19~60.9 nmol/L。该研究结果对丰富吲哚并咔唑类生物碱的种类、发现候选抗肿瘤药物等具有指导意义。 展开更多
关键词 星孢菌素 分离纯化 结构鉴定 抗肿瘤活性
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计及退役电池组寿命衰减的梯次储能系统功率分配优化策略
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作者 傅质馨 陈李 +2 位作者 刘皓明 王健 袁越 《太阳能学报》 北大核心 2025年第2期70-77,共8页
考虑梯次储能由不同健康状态的退役电池构成,基于梯次储能系统中电池组的荷电状态和健康状态提出一种功率分配优化策略。该策略计及不同健康状态电池组的寿命衰减对梯次储能系统寿命衰减的影响,基于电池组荷电状态和健康状态,考虑二者... 考虑梯次储能由不同健康状态的退役电池构成,基于梯次储能系统中电池组的荷电状态和健康状态提出一种功率分配优化策略。该策略计及不同健康状态电池组的寿命衰减对梯次储能系统寿命衰减的影响,基于电池组荷电状态和健康状态,考虑二者对电池组充放电能力影响的权重,通过对电池组充放电排序以实现最终的功率分配。首先,基于所构建梯次储能系统循环寿命衰减模型计算电池组的寿命衰减;然后,提出3种由电池组寿命衰减来计算梯次储能系统寿命衰减的计算方式,最后,以梯次储能系统寿命衰减最小为目标函数求解充放电排序策略中的权重值,实现不同电池组间的功率分配。在算例中通过与传统功率均分策略作比较,证明所提策略的优越性,并对所提的3种方式的优缺点进行对比分析。 展开更多
关键词 电池储能 能量管理 生命周期 退役电池 梯次储能系统
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利用小波变换研究2024-01-23乌什M_(S)7.1地震前重力异常特征
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作者 陈丽 刘代芹 +5 位作者 艾力夏提·玉山 阿卜杜塔伊尔·亚森 赵磊 丁宇 李秉烨 李瑞 《大地测量与地球动力学》 北大核心 2025年第3期279-283,共5页
利用南天山地区2020—2023年流动重力观测资料,获取2024-01-23乌什M_(S)7.1地震前不同时间尺度下区域重力场动态演化特征,并通过功率谱分析方法,获取各阶小波重力细节对应的近似场源深度。结果表明:1)流动重力(3 a尺度)结果显示,乌什M_(... 利用南天山地区2020—2023年流动重力观测资料,获取2024-01-23乌什M_(S)7.1地震前不同时间尺度下区域重力场动态演化特征,并通过功率谱分析方法,获取各阶小波重力细节对应的近似场源深度。结果表明:1)流动重力(3 a尺度)结果显示,乌什M_(S)7.1地震前,乌恰至巴楚地区和阿克苏地区重力变化呈现明显的四象限分布,震中位于四象限边缘及零值线附近;2)2020—2023年南天山地区重力场小波变换(4阶小波重力细节)结果显示,乌什M_(S)7.1地震前,乌恰至巴楚地区重力变化出现明显的四象限分布,震中位于四象限边缘及零值线附近。 展开更多
关键词 流动重力 小波变换 乌什地震
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轻量化古建筑青砖损伤检测方法研究
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作者 王茹 林浩杰 +1 位作者 陈丽 黄炜 《安全与环境学报》 北大核心 2025年第2期518-526,共9页
传统的古建筑青砖损伤检测通常采用人工识别的方式,存在工作量巨大、成本高等问题。为了解决该问题,提出一种轻量化古建筑青砖损伤检测算法(Lightweight Grey Bricks Damage Detection,Light-GBDD),并采用改进的轻量化FasterNet_T0模块... 传统的古建筑青砖损伤检测通常采用人工识别的方式,存在工作量巨大、成本高等问题。为了解决该问题,提出一种轻量化古建筑青砖损伤检测算法(Lightweight Grey Bricks Damage Detection,Light-GBDD),并采用改进的轻量化FasterNet_T0模块构建特征提取网络,以通过更少的模型参数完成损伤图像特征的提取;提出渐进卷积核空间金字塔池化模块(Gradual Convolutional Kernel Spatial Pyramid Pooling,GKSPP),用于降低由于最深层连续大核池化造成的细节特征信息丢失;通过特征金字塔网络和路径聚合网络构建特征融合网络,并引入卷积注意力模块(Convolutional Block Attention Module,CBAM),加强不同层级特征之间的关联,进而提高算法模型的检测精度;对v8DetectHead进行轻量化改进,进一步减少算法模型的参数量。最终,通过试验对Light-GBDD算法进行验证,试验结果显示,Light-GBDD算法较YOLOv8n算法在检测精度提高1.1百分点的情况下,参数量减少了69.1%,计算量降低了64.2%,存储量减少了66.7%,中央处理器(Central Processing Unit,CPU)推理帧数提高了100.9%,能够在移动设备上流畅运行。Light-GBDD算法有效降低了模型部署推理对计算设备的配置要求,实现了在低性能移动终端设备上的部署和推理。 展开更多
关键词 安全工程 古建筑 青砖 损伤检测 深度学习 轻量化
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一种随机应力谱在线分析方法及其在冶金起重机疲劳损伤分析中的应用
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作者 赵利强 饶培政 +3 位作者 丁克勤 陈力 郑惠泽 张理京 《北京化工大学学报(自然科学版)》 北大核心 2025年第1期83-92,共10页
冶金起重机工况复杂且长期连续进行吊装作业,其结构应力监测数据量大,连续周期长,使用常规的应力谱分析方法处理时会产生残波累积现象,导致结果准确性下降。针对此问题提出一种面向冶金起重机疲劳损伤评估的随机应力谱在线分析方法,首... 冶金起重机工况复杂且长期连续进行吊装作业,其结构应力监测数据量大,连续周期长,使用常规的应力谱分析方法处理时会产生残波累积现象,导致结果准确性下降。针对此问题提出一种面向冶金起重机疲劳损伤评估的随机应力谱在线分析方法,首先采用阶跃式雨流计数法对实时生成的随机应力数据进行分段计数并且实时输出随机应力谱,当循环分段计数产生的残波累积到一定程度时,对残波进行二次融合计数,并将此计数结果加入随机应力谱中修正实时计数结果,提升计数精度并用于后续的疲劳损伤评估。采用S-N曲线结合Miner损伤理论分析阶跃式雨流计数实时产生的应力谱并计算疲劳寿命,形成面向疲劳损伤评估的随机应力谱在线分析方法。分别采用四点雨流计数与阶跃式雨流计数对随机应力谱数据进行仿真实验,结果表明阶跃式雨流计数精度达到常规雨流计数的99%。使用该随机应力谱在线分析方法分析某冶金起重机副主梁连接处测点应力数据集并计算该测点处的有效疲劳寿命,结果证明该随机应力谱在线分析方法能够有效提升冶金起重机疲劳评估的实时性,评估结果合理,对起重机长期安全维护可提供及时有效的可靠依据。 展开更多
关键词 冶金起重机 疲劳评估 阶跃式雨流计数法 Miner疲劳理论 S-N曲线
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人工智能赋能中小学生综合素质评价的创新探索
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作者 陈丽 林文静 郑勤华 《中国考试》 北大核心 2025年第2期41-49,共9页
我国中小学开展综合素质评价已有二十余年,其重要性得到高度共识,地方财政投入巨大,但目前评价结果应用有限,指挥棒作用体现不足。究其原因,主要是评价方法无法保证结果的客观性和科学性。人工智能技术的突破性发展推进了表现性评价方... 我国中小学开展综合素质评价已有二十余年,其重要性得到高度共识,地方财政投入巨大,但目前评价结果应用有限,指挥棒作用体现不足。究其原因,主要是评价方法无法保证结果的客观性和科学性。人工智能技术的突破性发展推进了表现性评价方法的应用,成为提升我国综合素质评价能力的突破口和着力点。通过对我国学生综合素质评价发展历程的全面回顾,本研究系统总结了综合素质评价的现状与存在的问题、挑战,阐述了人工智能赋能综合素质评价的方向,并提出构建学生综合素质评价体系构想,以期为我国学生综合素质评价改革提供方向与策略指导。 展开更多
关键词 综合素质评价 人工智能 基础教育 表现性评价
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How do lateral septum projections to the ventral CA1 influence sociability?
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作者 Dan Wang Di Zhao +12 位作者 Wentao Wang Fengai Hu Minghu Cui Jing liu Fantao Meng Cuilan liu Changyun Qiu Dunjiang liu Zhicheng Xu Yameng Wang Yu Zhang Wei li chen li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1789-1801,共13页
Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role ... Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role of the connections between the LS and its downstream brain regions in social behavio rs remains unclea r.In this study,we conducted a three-chamber test using electrophysiological and chemogenetic approaches in mice to determine how LS projections to ventral CA1(vCA1)influence sociability.Our res ults showed that gamma-aminobutyric acid(GABA)-e rgic neuro ns were activated following social experience,and that social behavio rs were enhanced by chemogenetic modulation of these neurons.Moreover,LS GABAergic neurons extended their functional neural connections via vCA1 glutamatergic pyramidal neurons,and regulating LSGABA→vCA1Gluneural projections affected social behaviors,which were impeded by suppressing LSprojecting vCA1 neuronal activity or inhibiting GABAAreceptors in vCA1.These findings support the hypothesis that LS inputs to the vCA1 can control social prefe rences and social novelty behaviors.These findings provide new insights rega rding the neural circuits that regulate sociability. 展开更多
关键词 chemogenetics GABA receptor GABAergic neurons glutamatergic neurons lateral septum neural excitability neural projection social novelty social preference ventral CA1
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Intensifying recovery of metallic aluminum in secondary aluminum dross by alkali roasting−water leaching
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作者 chen li Wei liU +3 位作者 Fen JIAO liang-min DONG Shi-yang liU Wen-qing QIN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第12期4063-4074,共12页
An innovative process was proposed to recover metallic aluminum from secondary aluminum dross(SAD)by alkali roasting−water leaching.Thermodynamic calculations and experimental results were used to illustrate the phase... An innovative process was proposed to recover metallic aluminum from secondary aluminum dross(SAD)by alkali roasting−water leaching.Thermodynamic calculations and experimental results were used to illustrate the phase transformation and reaction mechanism of the alkali roasting process.The leaching behaviors of roasted residue were also analyzed.Under optimal conditions,the aluminum extraction rate reached 93.08%.In addition,the kinetics of the water leaching of roasted products was studied through shrinking core model,and it was revealed that the leaching process of aluminum was in accord with diffusion control.The apparent activation energy of the leaching process was calculated to be 3.44 kJ/mol.Based on the above study,the underlying mechanism of the alkali roasting−water leaching was clarified. 展开更多
关键词 secondary aluminum dross aluminum recovery selective separation alkali roasting water leaching
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A 48-bp deletion upstream of LIGULELESS 1 alters rice panicle architecture
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作者 linhua Wu Min Hu +6 位作者 Shuwei Lyu Wenfeng chen Hang Yu Qing liu Wei He chen li Zuofeng Zhu 《The Crop Journal》 SCIE CSCD 2024年第2期354-363,共10页
Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANIC... Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANICLE 1(OP1),a gain-of-function allele of LIGULELESS 1(LG1),controlling the spread-panicle phenotype.This allele results from a 48-bp deletion in the LG1 upstream region and promotes pulvinus development at the base of the primary branch.Increased OP1 expression and altered panicle phenotype in chimeric transgenic plants and upstream-region knockout mutants indicated that the deletion regulates spread-panicle architecture in the mutant spread panicle 1(sp1).Knocking out BRASSINOSTEROID UPREGULATED1(BU1)gene in the background of OP1 complementary plants resulted in compact panicles,suggesting OP1 may regulate inflorescence architecture via the brassinosteroid signaling pathway.We regard that manipulating the upstream regulatory region of OP1 or genes involved in BR signal pathway could be an efficient way to improve rice inflorescence architecture. 展开更多
关键词 Upstream region Panicle architecture Gene expression BR Rice
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Evolution and spatiotemporal analysis of earthquake public opinion based on social media data
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作者 chenyu Wang Yanjun Ye +2 位作者 Yingqiao Qiu chen li Meiqing Du 《Earthquake Science》 2024年第5期387-406,共20页
As critical conduits for the dissemination of online public opinion,social media platforms offer a timely and effective means for managing emergencies during major disasters,such as earthquakes.This study focuses on t... As critical conduits for the dissemination of online public opinion,social media platforms offer a timely and effective means for managing emergencies during major disasters,such as earthquakes.This study focuses on the analysis of online public opinions following the Maduo M7.4 earthquake in Qinghai Province and the Yangbi M6.4 earthquake in Yunnan Province.By collecting,cleaning,and organizing post-earthquake Sina Weibo(short for Weibo)data,we employed the Latent Dirichlet Allocation(LDA)model to extract information pertinent to public opinion on these earthquakes.This analysis included a comparison of the nature and temporal evolution of online public opinions related to both events.An emotion analysis,utilizing an emotion dictionary,categorized the emotional content of post-earthquake Weibo posts,facilitating a comparative study of the characteristics and temporal trends of online public emotions following the earthquakes.The findings were visualized using Geographic Information System(GIS)techniques.The analysis revealed certain commonalities in online public opinion following both earthquakes.Notably,the peak of online engagement occurred within the first 24 hours post-earthquake,with a rapid decline observed between 24 to 48 hours thereafter.The variation in popularity of online public opinion was linked to aftershock occurrences.Adjusted for population factors,online engagement in areas surrounding the earthquake sites and in Sichuan Province was significantly high.Initially dominated by feelings of“fear”and“surprise”,the public sentiment shifted towards a more positive outlook with the onset of rescue operations.However,distinctions in the online public response to each earthquake were also noted.Following the Yangbi earthquake,Yunnan Province reported the highest number of Weibo posts nationwide;in contrast,Qinghai Province ranked third post-Maduo earthquake,attributable to its smaller population size and extensive damage to communication infrastructure.This research offers a methodological approach for the analysis of online public opinion related to earthquakes,providing insights for the enhancement of post-disaster emergency management and public mental health support. 展开更多
关键词 internet public opinion topic clustering emotional analysis psychological crisis intervention
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不同基质配方处理对蓝莓果实产量及品质的影响
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作者 裴嘉博 刘辉 +9 位作者 马振华 钟林炳 骆慧枫 刘禹姗 邓宇 黄康康 张琛 陈丽 高国忠 郗笃隽 《陕西农业科学》 2025年第1期104-111,115,共9页
以蓝莓‘优瑞卡’为试材,用椰糠、国产草炭、山沙、立陶宛泥炭和珍珠岩等材料按照不同比例均匀混拌成15种基质配方,测定分析不同基质配方处理下蓝莓果实产量、外观特征和内在品质,评价不同基质对蓝莓产量和品质的影响,筛选出适合当地使... 以蓝莓‘优瑞卡’为试材,用椰糠、国产草炭、山沙、立陶宛泥炭和珍珠岩等材料按照不同比例均匀混拌成15种基质配方,测定分析不同基质配方处理下蓝莓果实产量、外观特征和内在品质,评价不同基质对蓝莓产量和品质的影响,筛选出适合当地使用的蓝莓基质栽培配方,为生产推广提供理论指导。结果表明,不同基质配方处理对蓝莓果实产量和品质具有不同程度的影响。处理T1(椰糠∶国产草炭∶山沙=2∶2∶1)的基质对果实品质的综合提升效果最佳,果实外观特征、内在品质和产量显著高于CK,总酸(柠檬酸、奎尼酸、苹果酸、莽草酸)、总黄酮醇显著低于CK,其次是处理T5(立陶宛泥炭∶国产草炭∶山沙=2∶1∶1),处理T3(椰糠∶国产草炭∶山沙=1∶1∶1)位列第三;处理T1的产量、纵径、总花色苷最高,处理T5(立陶宛泥炭∶国产草炭∶山沙=2∶1∶1)的果实单果重、横径最大,处理T3(椰糠∶国产草炭∶山沙=1∶1∶1)的果实维生素C、总糖(葡萄糖、果糖、蔗糖)、糖酸比、固酸比含量最高,处理T11(立陶宛泥炭∶椰糠=1∶1)的蓝莓果实总黄酮醇含量最高。综合分析,提升蓝莓果实品质效果较好的三个基质组合依次为处理T1(椰糠∶国产草炭∶山沙=2∶2∶1)、T5(立陶宛泥炭∶国产草炭∶山沙=2∶1∶1)、T3(椰糠∶国产草炭∶山沙=1∶1∶1)。 展开更多
关键词 蓝莓 基质 果实品质
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光质对蓝莓果实品质的影响
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作者 裴嘉博 刘辉 +6 位作者 钟林炳 骆慧枫 刘禹姗 阮若昕 张琛 陈丽 郗笃隽 《农学学报》 2025年第2期64-68,共5页
为科学指导蓝莓生产中补光设备的应用,以蓝莓‘优瑞卡’为试材,研究5个光质处理组合对蓝莓果实品质的影响。结果表明,与对照(不补光)相比,T2处理(距离蓝莓植株顶端30 cm处并排2列光照强度28μmol/(m^(2)·s),红光:蓝光=5:1,单根功率... 为科学指导蓝莓生产中补光设备的应用,以蓝莓‘优瑞卡’为试材,研究5个光质处理组合对蓝莓果实品质的影响。结果表明,与对照(不补光)相比,T2处理(距离蓝莓植株顶端30 cm处并排2列光照强度28μmol/(m^(2)·s),红光:蓝光=5:1,单根功率27 W,长度1220 mm的灯管)的单果重、纵横径、总花色苷和总黄酮醇含量最大,高于对照,但差异不显著。T4处理(距离蓝莓植株顶端30 cm处并排2列光照强度21μmol/(m^(2)·s)、红光:蓝光=1.4:1、单根功率16 W、长度1080 mm的灯管)的固酸比和糖酸比显著高于对照,果实总酸(柠檬酸、苹果酸、莽草酸)含量显著低于对照;硬度、可溶性固形物含量最大,高于对照,但差异不显著。T5处理[距离蓝莓植株顶端30 cm处并排2列,底部(即蓝莓盆沿处)1列灯,光照强度21μmol/(m^(2)·s),光谱红光:蓝光=1.4:1,单根功率16 W,长度1080 mm的灯管]的总糖含量(葡萄糖、果糖、蔗糖)最高,显著高于对照。处理T4综合得分最高。由此可见,在距离蓝莓植株顶端30 cm处并排2列光照强度为21μmol/(m^(2)·s)、光谱为红光:蓝光=1.4:1、单根功率为16 W、长度为1080 mm的灯管,对蓝莓果实品质的综合提升效果最好。 展开更多
关键词 蓝莓 红光 蓝光 果实品质
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给氧负压封闭引流联合湿润烧伤膏序贯治疗高海拔地区下肢慢性溃疡疗效分析
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作者 陈莉 李永忠 +4 位作者 李云飞 卓玛木 仁青夺机 嘉央益西 杨雨婷 《中国烧伤创疡杂志》 2025年第1期1-5,共5页
目的探讨给氧负压封闭引流联合湿润烧伤膏序贯治疗高海拔地区下肢慢性溃疡的临床疗效。方法选取2019年1月至2023年3月若尔盖县人民医院收治的60例下肢慢性溃疡患者作为研究对象,按照创面不同治疗方法将其分为观察组(30例)和对照组(30例)... 目的探讨给氧负压封闭引流联合湿润烧伤膏序贯治疗高海拔地区下肢慢性溃疡的临床疗效。方法选取2019年1月至2023年3月若尔盖县人民医院收治的60例下肢慢性溃疡患者作为研究对象,按照创面不同治疗方法将其分为观察组(30例)和对照组(30例),观察组患者予以给氧负压封闭引流联合湿润烧伤膏序贯治疗,对照组患者单纯予以湿润烧伤膏治疗,对比两组患者创面肉芽组织状态、病原菌感染情况、愈合率以及住院时间。结果治疗3周后,观察组患者创面肉芽组织评分明显高于对照组、病原菌阳性率低于对照组(Z/χ^(2)=-4.332、4.800,P<0.001、P=0.028);观察组患者治疗3周后创面愈合率明显高于对照组、住院时间明显短于对照组(t=6.517、7.211,P均<0.001)。结论给氧负压封闭引流联合湿润烧伤膏序贯治疗高海拔地区下肢慢性溃疡创面,能够有效促进肉芽组织生长,抑制病原菌增殖,加快创面愈合,缩短住院时间。 展开更多
关键词 高海拔地区 给氧 负压封闭引流 湿润烧伤膏 下肢慢性溃疡 创面
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数字经济对国家制造业贸易网络地位的影响效应——来自“一带一路”国家的经验证据
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作者 陈砺 郜霞妹 《财经论丛》 北大核心 2025年第3期16-26,共11页
本文采用社会复杂网络分析法构建2010—2020年52个“一带一路”国家制造业有向加权贸易网络,检验数字经济对制造业贸易网络地位的影响效应。研究发现,数字经济显著提高“一带一路”国家制造业贸易网络地位,在技术密集型制造业和发达经... 本文采用社会复杂网络分析法构建2010—2020年52个“一带一路”国家制造业有向加权贸易网络,检验数字经济对制造业贸易网络地位的影响效应。研究发现,数字经济显著提高“一带一路”国家制造业贸易网络地位,在技术密集型制造业和发达经济体中的促进作用更强,而技术进步和贸易成本下降是数字经济驱动制造业贸易网络地位攀升的重要途径;“一带一路”国家数字经济发展对制造业贸易网络地位的提升存在空间溢出效应,有助于形成区域间制造业协调发展、合作共赢的经济格局。上述结论为推动“一带一路”制造业贸易网络布局优化、促进各国贸易网络地位协同提升给予有益的启示。 展开更多
关键词 数字经济 “一带一路” 贸易网络地位 制造业 社会复杂网络分析
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Differential pressure difference based altitude control of a stratospheric satellite
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作者 陈丽 WANG Xiaoliang 《High Technology Letters》 EI CAS 2024年第1期1-12,共12页
An autonomous altitude adjustment system for a stratospheric satellite(StratoSat)platform is proposed.This platform consists of a helium balloon,a ballonet,and a two-way blower.The helium balloon generates lift to bal... An autonomous altitude adjustment system for a stratospheric satellite(StratoSat)platform is proposed.This platform consists of a helium balloon,a ballonet,and a two-way blower.The helium balloon generates lift to balance the platform gravity.The two-way blower inflates and deflates the ballonet to regulate the buoyancy.Altitude adjustment is achieved by tracking the differential pressure difference(DPD),and a threshold switching strategy is used to achieve blower flow control.The vertical acceleration regulation ability is decided not only by the blower flow rate,but also by the designed margin of pressure difference(MPD).Pressure difference is a slow-varying variable compared with altitude,and it is adopted as the control variable.The response speed of the actuator to disturbance can be delayed,and the overshoot caused by the large inertia of the platform is inhibited.This method can maintain a high tracking accuracy and reduce the complexity of model calculation,thus improving the robustness of controller design. 展开更多
关键词 stratospheric satellite(StratoSat) differential pressure difference(DPD) altitude adjustment threshold switching strategy margin of pressure difference(MPD)
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