Results 21 to 30 of about 1,214,007 (162)
ABSTRACT This study presents an assessment of four representative expansive additives—calcium sulphoaluminate–calcium oxide, magnesium oxide, sodium lauryl sulfate, and sodium abietate—and their effects on the expansion behavior, mechanical development, and microstructural characteristics of cemented paste backfill (CPB).
Lijie Guo +5 more
wiley +1 more source
森林植被的生态需水可以理解为林地的蒸散耗水量,与土壤含水量关系密切.根据土壤水分有效性的划分,林木暂时凋萎含水量和生长阻滞含水量分别是能保证林木基本生存和正常生长时土壤含水量的下限,因此,相应的林地耗水量分别为林地的最小生态需水定额和适宜生态需水定额,其数值通过计算林地的潜在蒸散并利用土壤水分修正系数和林木系数进行订正获得.根据最新遥感图像资料,在GIS支持下,计算了泾河流域现有林地生长季的最小生态需水量和适宜生态需水量,分别为203 960×104 m3和340 330×104 m3.
何永涛 闵庆文 李文华 李贵才
doaj
Read the free Plain Language Summary for this article on the Journal blog. Abstract Organic phosphorus mineralization is a critical process in the phosphorus cycle, governing phosphorus bioavailability for plants. The PhoD gene, which encodes the key enzyme alkaline phosphatase, serves as a valuable biomarker for this process.
Sandhya Mishra +3 more
wiley +1 more source
Distribution, scale, and drivers of mass mortality events in Europe's freshwater bivalves
Abstract Mass mortality events (MMEs) are decimating populations and compromising key ecosystem functions around the globe. One taxon particularly vulnerable to MMEs is freshwater bivalve mollusks. This group has important ecosystem engineering capacities and includes highly threatened and highly invasive taxa.
Daniel A. Cossey +39 more
wiley +1 more source
为探讨滴灌条件下棉田中地膜残留含量对土壤水盐及作物生长的影响,在棉田设置150(T1),230(T2),465(T3),857(T4),1 250(T5),1 640(T6) kg/hm2、原试验地土壤(CK1)和无残膜对照组(CK2)8种残膜含量处理,分析了地膜残留含量对滴灌棉田中的土壤水盐、土壤和作物根系氮素以及产量的影响。结果表明:随着残膜含量的增加,土壤含水率逐渐降低,土壤盐分的富集效果逐渐增强;0—40 cm土层土壤水盐变异程度与残膜含量呈正相关,T5和T6的土壤水盐变异系数(CV)明显较大 ...
徐阳 +4 more
doaj
ABSTRACT Low conductivity, slow ion‐diffusion, and limited reactive sites are common problems in electrocatalysts and electrode materials. In this study, a complex NiTe–CoTe heterojunction with abundant Te vacancies embedded in N, P, and F co‐doped hollow carbon nanorods (NiTe1−x–CoTe1−x/NPFC) was fabricated via a simple ionic liquid‐assisted ...
Mingjie Yi +7 more
wiley +1 more source
为了分离绝缘纸老化程度和水分对频域介电谱的影响及提高变压器绝缘纸老化程度和水分含量评估精度,文中通过开展加速热老化试验制备了老化程度和含水量均不相同的5组油纸绝缘试样,并对各组试样进行tanδ频谱测试。试验结果表明,在10-310-1Hz频段内,tanδ曲线随绝缘纸老化程度增加而上升;在10-3102Hz频段内tanδ曲线随绝缘纸含水量增大显著上升,在特征频段10-1102Hz和10-310-1Hz内求取tanδ曲线对频率的积分值Sm和SDP分别作为表征水分含量和老化程度的特征量 ...
曹建军, 隋彬, 杨飞豹, 尹小兵
doaj
ABSTRACT Objective Complete hydatidiform mole and coexisting normal fetus (CHMCF) is a rare condition for which there is significant heterogeneity in diagnosis, counseling and management of complications. The objective of this study was to summarize the prevalence of clinical outcomes in reported cases of CHMCF.
N. Salmeri +8 more
wiley +1 more source
为了更准确地进行油纸绝缘水分含量的测量,探寻老化产物中最为主要的酸对于水分测量的影响,从而为变压器绝缘状态评估提供可靠指导,文中在实验室条件下制备含有不同水分含量以及含有不同类型不同酸值的油纸绝缘试样,采用极化/去极化电流法(PDC)对有机酸对于水分测量的影响开展了研究。试验结果表明:乙酸在油纸间的分布会受到水分含量变化的影响,而硬脂酸的分布并不受含水量的影响;乙酸和硬脂酸对去极化电流曲线影响不同,乙酸对去极化电流曲线尾端影响很大,而硬脂酸对去极化电流曲线首段影响严重 ...
夏国强 +4 more
doaj
ABSTRACT Developing low‐energy‐input electrocatalytic systems for efficient hydrogen production is crucial for advancing sustainable energy technologies. The overall hydrazine splitting (OHzS) has emerged as a promising strategy to reduce the overall energy consumption by replacing the sluggish oxygen evolution reaction.
Haozhou Chen +13 more
wiley +1 more source

