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Deep-learning enabled atomic insights into the phase transitions and nanodomain topology of lead-free(K,Na)NbO_(3) ferroelectrics

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Science China Materials 2024年第9期67卷 3029-3038页

作者： xu Zhang Bei Li Ji Zou hanxing Liu Ben xu Kai Liu School of Materials Science and Engineering Research Center for Materials Genome EngineeringWuhan University of TechnologyWuhan430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China International School of Materials Science and Engineering Wuhan University of TechnologyWuhan430070China Graduate School China Academy of Engineering PhysicsBeijing100193China

Lead-free K_(x)Na_(1-x)NbO_(3)(KNN)perovskites have garnered increasing attention due to their exceptional ferropiezoelectric properties,which are effectively tuned via polymorphic structures and domain ***,atomic insights into the underlying nanomechanisms governing the ferroelectricity of KNNs amidst varying factors such as composition,phase,and domain are still ***,we perform molecular dynamics simulations of phase transitions and domain dynamics for KNNs with various K/Na ratios(x=0.25∼1.0)by using ab-initio accuracy deep learning potential(DP).As a demonstration of its transferability,the newly developed DP model shows quantum accuracy in terms of the equation of states,elastic constants,and phonon dispersion relations for various KNbO_(3)and K_(0.5)Na_(0.5)NbO_(3).Furthermore,intricate temperature-dependent phase transitions and domain formation of KNNs are extensively and quantitatively *** indicate that for KNNs with compositions x ranging from 0.25 to 1.0,the paraelectric-to-ferroelectric phase transition of KNNs is driven primarily by the order-disorder effect,while the displacive effect is dominant in the subsequent ferroelectric phase ***,flux-closure or herringbone-like nanodomain patterns arranged with 90°domain walls formed close to the experimental *** analyses reveal that favorable 90°domain wall formation becomes more challenging with increasing Na content due to distinct oxygen octahedron distortion arising from the different ionic radii of K/Na *** is envisioned that the combination of unified DP and atomistic simulations will help offer a robust solution for more accurate and efficient in silico explorations of complex structural,thermodynamic,and ferroelectric properties for relevant energy storage and conversion materials.

关键词： KNN molecular dynamics deep potential phase transitions domain dynamics

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高校学生党员发展质量保障体系构建研究

襄阳职业技术学院学报 2020年第2期19卷 110-113页

作者：纪书燕许晗星华南理工大学广州学院广州510800

高校学生党员发展质量保障体系为:完善组织设置,选好配齐党建工作队伍是前提;建立党员发展标准,健全规章制度是基础;注重过程管理,严格发展程序是关键;加强教育培养,教育管理相结合是重点。

关键词：高校党员发展质量保障体系

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浅水潮综合预报方法的研究

海洋与湖沼 1982年第3期 207-217页

作者：徐汉兴上海航道局设计研究所

本文以上海港的潮汐预报方法为例,阐述了适用于河口及我国沿海其他浅水港口潮汐预报的一种综合性方法,它包括对天文潮、增减水及其综合水位的预报方法与效果问题的研究等。上海港扼长江口、濒东海之滨,潮汐属非正规半日浅海潮,常受台... 详细信息

本文以上海港的潮汐预报方法为例,阐述了适用于河口及我国沿海其他浅水港口潮汐预报的一种综合性方法,它包括对天文潮、增减水及其综合水位的预报方法与效果问题的研究等。上海港扼长江口、濒东海之滨,潮汐属非正规半日浅海潮,常受台风、寒潮和长江径流等水文气象因素的影响,航道水深较浅,潮汐水流情况复杂。近十多年来,通过实践,逐

关键词：分潮潮汐调和分析潮汐谐波分析水文分析潮高调和常数潮位预报预报方法

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大学生就业指导课程创新模式探究

科教文汇 2019年第26期 45-46页

作者：刘建斌马萍许晗星华南理工大学广州学院

随着中国经济的蓬勃发展,以及中国教育水平的提升,大学入学率连年再创新高,而逐年上升的大学生入学率也就表示着就业市场的日趋激烈。在这样的大环境下,大学生的就业能力也就成了在校必不可少的培养目标,也成为社会关注的焦点。但大学... 详细信息

随着中国经济的蓬勃发展,以及中国教育水平的提升,大学入学率连年再创新高,而逐年上升的大学生入学率也就表示着就业市场的日趋激烈。在这样的大环境下,大学生的就业能力也就成了在校必不可少的培养目标,也成为社会关注的焦点。但大学生由于本身的一些局限性和经验缺乏,其就业存在着一些比较难克服的问题,而在大学课程中虽然有相应的大学生就业指导课程,但仍然存在着一些问题,不能够为大学生解决实际问题,或者已经跟不上当下社会的需求。本文将从大学生就业指导课程角度来探讨当前大学生就业指导课程的创新模式,并试着提出了基于大学生就业能力提升的就业指导课程教学创新策略。

关键词：大学生就业指导课程创新模式

江淮分水岭区域植被覆盖与人类活动强度的时空动态演化

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黑龙江工程学院学报 2020年第1期34卷 27-32,48页

作者：徐韩星徐建辉张榕榕王凯王丽滁州学院地理信息与旅游学院

利用江淮分水岭区域2000—2015 NDVI月合成数据、降水与气温数据、高程数据以及社会经济数据,采用一元线性趋势分析法、残差分析法分析江淮分水岭区域16 a植被覆盖情况以及变化趋势与人类活动强度的关系。结果表明:1)江淮分水岭区域的... 详细信息

利用江淮分水岭区域2000—2015 NDVI月合成数据、降水与气温数据、高程数据以及社会经济数据,采用一元线性趋势分析法、残差分析法分析江淮分水岭区域16 a植被覆盖情况以及变化趋势与人类活动强度的关系。结果表明:1)江淮分水岭区域的植被覆盖指数在16 a内呈现整体上升趋势,但合肥、六安这两个经济发展速度较快的中心城区,植被覆盖指数有所降低。2)通过计算与分析可知,0.0061

关键词：江淮分水岭区域植被覆盖时空变化人类活动强度

SiamCPN:Visual tracking with the Siamese center-prediction network

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Computational Visual Media 2021年第2期7卷 253-265页

作者： Dong Chen Fan Tang Weiming Dong hanxing Yao Changsheng xu School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100040China NLPR Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence Jilin UniversityChangchun 130012China CASIA-LLVISION Joint Lab Beijing 100190China LLVISION Technology Co. LTD.Beijing 100190China

Object detection is widely used in object tracking;anchor-free object tracking provides an end-to-end single-object-tracking *** this study,we propose a new anchor-free network,the Siamese center-prediction network(SiamCPN).Given the presence of referenced object features in the initial frame,we directly predict the center point and size of the object in subsequent frames in a Siamese-structure network without the need for perframe post-processing *** other anchor-free tracking approaches that are based on semantic segmentation and achieve anchor-free tracking by pixel-level prediction,SiamCPN directly obtains all information required for tracking,greatly simplifying the model.A center-prediction sub-network is applied to multiple stages of the backbone to adaptively learn from the experience of different branches of the Siamese *** model can accurately predict object location,implement appropriate corrections,and regress the size of the target bounding *** to other leading Siamese networks,SiamCPN is simpler,faster,and more efficient as it uses fewer *** demonstrate that our method outperforms other leading Siamese networks on GOT-10K and UAV123 benchmarks,and is comparable to other excellent trackers on LaSOT,VOT2016,and OTB-100 while improving inference speed 1.5 to 2 times.

关键词： s Siamese network single object tracking anchor-free center point detection

Ⅰ型神经纤维瘤病相关巨大丛状神经纤维瘤破裂出血急诊处理及围术期管理策略

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中国修复重建外科杂志 2024年第10期38卷 1180-1185页

作者：朱宝晨肖杨廖睿恒赵焓杏许学文张艳阁四川大学华西医院烧伤整形外科成都610041

目的综述Ⅰ型神经纤维瘤病(neurofibromatosis type 1,NF1)相关巨大丛状神经纤维瘤(plexiform neurofibroma,PNF)破裂出血的急诊处理及围术期管理策略,提供一种系统处理流程,以提高巨大PNF治疗效果和患者生存质量。方法回顾巨大PNF破裂... 详细信息

目的综述Ⅰ型神经纤维瘤病(neurofibromatosis type 1,NF1)相关巨大丛状神经纤维瘤(plexiform neurofibroma,PNF)破裂出血的急诊处理及围术期管理策略,提供一种系统处理流程,以提高巨大PNF治疗效果和患者生存质量。方法回顾巨大PNF破裂出血的相关治疗文献,并结合临床实践经验,总结当前巨大PNF破裂出血诊断方法、治疗方案及围术期综合管理措施。结果通过实施综合诊疗策略(包括早期诊断、影像学评估、急诊超选择性动脉栓塞术与手术切除相结合),不仅能够有效控制急性出血,还可以降低手术中大出血风险,减少术后并发症,从而显著提高治疗成功率和患者生存质量。结论对于NF1相关的巨大PNF破裂出血,在多学科团队合作下采用急诊超选择性动脉栓塞术结合手术切除治疗,可有效提高治疗成功率,快速控制出血、缩小瘤体以及降低患者死亡率。未来研究需要继续关注巨大PNF破裂出血患者治疗后长期生存质量及进一步优化治疗方案。

关键词：巨大丛状神经纤维瘤 Ⅰ型神经纤维瘤病破裂出血动脉栓塞手术切除

基于数据挖掘探讨中医药治疗胃癌术后用药规律

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中国中医药图书情报杂志 2024年第3期48卷 64-69页

作者：张成成陈民梁寒星寇玉徐海荣扬州大学医学院江苏省中西医结合老年病防治重点实验室江苏扬州225000

目的基于数据挖掘技术分析中医药治疗胃癌术后的药物配伍规律及核心处方,以期为临床用药提供参考。方法计算机检索中国知识资源总库(CNKI)、万方数据知识服务平台(万方数据)、中文科技期刊数据库(维普网)建库至2022年12月1日中医药治疗... 详细信息

目的基于数据挖掘技术分析中医药治疗胃癌术后的药物配伍规律及核心处方,以期为临床用药提供参考。方法计算机检索中国知识资源总库(CNKI)、万方数据知识服务平台(万方数据)、中文科技期刊数据库(维普网)建库至2022年12月1日中医药治疗胃癌术后的相关文献,经数据筛选及规范化处理后,运用古今医案云平台2.3.5,进行中药频次统计、属性统计、关联规则分析、聚类分析及复杂网络分析,探析中医药治疗胃癌术后的用药频次、性味归经、核心处方等用药规律。结果共纳入处方173首,涉及药物277味,频次最高的药物为白术(125次)。药性以平、温为主,药味以甘、苦为主,主归脾经、肺经、胃经。关联分析显示,白术-茯苓、白术-黄芪、白术-甘草等关联度最高。聚类分析可知治疗胃癌术后中药可分为4组。复杂网络分析发现其核心处方为六君子汤加减。结论中医药治疗胃癌术后以扶正补虚为主,重用益气健脾和胃之品,兼顾燥湿化痰、消食除积、祛瘀抗癌为用药特点,标本同治,攻补兼施。

关键词：古今医案云平台胃癌术后中医药用药规律

Effects of Simulated Grazing Pattern and Nitrogen Supply on Plant Growth in a Semiarid Region of Northern China

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Acta Botanica Sinica 2004年第9期46卷 1032-1039页

作者： YUANZhi-You LILing-Hao hanxing-Guo JIANGFeng-He LINGuo-Hui ZHAOMing-xu RENLi-Yun LaboratoryofQuantitativeVegetationEcology InstituteofBotanyTheChineseAcademyofSciencesBeijing100093China GrasslandManagementStationofDuolunCountyDuolun027300 NeiMongolChina AnimalHusbandryBureauofTaipusi Taipusi027000NeiMongolChina

Grazing in grassland ecosystems affects plant growth by removing biomass and depositing excretal nutrients. However, grazing is not uniformly distributed in space. The spatial pattern of defoliation and excretion deposition by herbivores across vegetation mosaics has been frequently discussed, but rarely spatially quantified. A 60-day field experiment in a native semiarid grassland community was conducted to examine the responses of plant growth to simulated grazing pattern and varying nitrogen *** were subjected to five defoliation treatments determined by circularly clipped patches of different size (0, 10, 20, 40, 80cm in radius), and four nitrogen supply levels in soils (0, 5, 10, 20g N/m^2). It was detected that defoliation had reduced primary productivity by 41.5% whereas fertilization had increased it by 57.8%. The negative effect of defoliation was greater in the smallest, fertilized patches. N addition had been found to have altered the effect of defoliation, as plants growing at higher nitrogen levels were more negatively affected by defoliation than plants with no supplementary application of nitrogen. These results indicated that the magnitude of defoliation response for an individual plant was modulated by not only defoliation itself, but also other factors, such as nutrient availability, The increase in the ratio of live to dead plant parts suggested that urine deposition delayed the senescence of plants. The results also showed that (1) the effect of defoliation on primary productivity was affected by the patch size, and (2) nitrogen addition (simulated urine deposition) could increase primary productivity and affect the response to defoliation more obviously in the smaller patches than in the larger ones.

关键词：氮半干旱地区中国北方地区放牧牧场施肥植物生长