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Ultrasound in Obstetrics &Gynecology, Volume 67, Issue 3, Page 376-384, March 2026.ABSTRACT Objective To investigate whether combining abnormal morphological features observed on ultrasound in live pregnancies that ended in a first‐trimester miscarriage can predict an abnormal karyotype. Methods This retrospective observational cohort study was conducted at the early‐pregnancy assessment unit at University College London Hospital ...
T. Setty +5 more
wiley +1 more source
Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Photocatalytic molecular oxygen (O2) activation provides a sustainable approach to produce singlet oxygen (1O2) for organic contaminants detoxification. However, the charge carriers‐involved pathway usually suffers from unsatisfactory 1O2 production efficiency owing to energy loss caused by photogenerated hole‐mediated superoxide species (•O2−
Yan‐Biao Shi +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2018 针对淮北平原黄潮土水土流失严重的问题，为揭示其产流产沙规律，利用五道沟水文实验站大型人工模拟降雨径流试验场，开展了40，60，80 mm/h 3个雨强及5°，10°，15° 3个坡度产流产沙规律试验模拟。结果表明：坡面初始产流时间随坡度、雨强的增大而缩短，雨强、坡度越大缩短越不明显；单位时间产流、产沙量随降雨时间变化的转折点在产流后6~15 min，单位时间产流量随降雨时间变化表现为前期快速增加，中期缓慢增加，后期平稳，其中40，60 mm/h雨强单位时间产流量随坡度增加而减小，80 mm ...
杜明成 +4 more
doaj
, 1997 国民经济帐户不同于企业会计帐户。它以宏观经济循环过程为主线设置帐户，并围绕相应环节的宏观经济统计指标组织核算；各有关帐户之间，内容前后衔接、项目勾稽对应，并在复式簿记方法的基础上形成科学、严谨 ...
杨灿
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT A major challenge in fabricating eutectic NiTiNb alloys is the incomplete melting of Nb due to its much higher melting point than the NiTi matrix. In this work, a novel electron‐beam freeform additive manufacturing strategy is developed to eliminate unmelted Nb particles and achieve a fully eutectic structure through independent dual‐wire ...
Qing‐Da Zhang +9 more
wiley +1 more source
Progress in the Development of Microwave High Power SiGe HBT's and Its Applications [PDF]
, 2005 文章论述了SiGe异质结双极晶体管(HBT)在微波功率领域应用的优势,详细介绍了微波功率SiGe HBT的结构设计方法,以及主要影响器件性能的材料和结构因素,评述了其最新进展及今后发展方向。国家自然科学基金重点资助项目(60336010);; 福建省青年科技人才创新项目(2004J021 ...
徐剑芳, 李成, 赖虹凯
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Silicon oxide (SiO) is becoming the main anode for high‐energy lithium‐ion batteries because of its ease of manufacture, outstanding cycling stability, and high capacity. However, low initial Coulombic efficiency (ICE) caused by the irreversible reaction of silica, as the main issue, strictly limits its commercial applications.
Hailong Mei +5 more
wiley +1 more source
Shuitu Baochi Xuebao, 2017 为探求鲁中南山丘区坡面侵蚀规律，选取山东省泰安市药乡小流域，以4个坡面径流小区的降雨、径流、泥沙实测资料为基础，探究不同措施下各小区产流产沙的差异性和导致产流的降雨量临界值，并利用相关分析方法探究径流泥沙与降雨的相关关系。结果表明：（1）导致径流产生的降雨量临界值表现为裸地＜农地＜草地，草地临界降雨量分别比梯田种植、横坡种植、裸地高0.2，2.8，3.8 mm；（2）在相同的降雨条件下，各小区产流产沙均为裸地最大，其中产流量约为农地的1.3~4.3倍，约为草地的2.8倍；产沙量约为农地的3.1~10 ...
程甜甜 +4 more
doaj
Shuitu Baochi Xuebao, 2021 水土流失已成为我国主要的生态环境问题之一。基于安徽大别山区江子河小流域2012-2019年自然降雨径流泥沙观测资料，探讨雨型对不同农作物措施坡面产流产沙的影响，采用随机森林算法分析降雨因子与水沙之间的关系。结果表明，在不同场次降雨中，径流量、土壤流失量随降雨场次变化规律较一致，红薯措施产流量及土壤流失量较大，茶叶措施最小。降雨分为3类：A型降雨（低频率、长历时、大雨量、高雨强）、B型降雨（高频率、短历时、小雨量、低雨强）、C型降雨（较低频率、较长历时、中等雨量、较高雨强），对产流产沙的影响表现为A型 ...
张嘉懿 +3 more
doaj
A Study on Financial Development and Structural Optimization of China's Manufacturing Export Products [PDF]
, 2010 改革开放以来，我国制造业取得了迅猛的发展，并推动了我国工业化的进程。然而，受2008年全球金融危机的影响，国外市场需求量的锐减导致我国制造业，特别是主导出口的制造企业受到了前所未有的冲击，未来世界经济发展的格局也必将在次贷危机和金融危机全面爆发后进行重新调整。只有加快推进出口结构优化，中国制造业才能在未来更加激烈的国际竞争中胜出。随着我国市场经济的完善，我国金融行业也经历着从计划经济向市场经济的巨大转变。如何推进我国的金融发展，发挥金融的资源配置作用，进而推动我国制造业出口结构优化 ...
陈清
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