Results 31 to 40 of about 1,537,373 (154)

黄土高原水蚀风蚀复合区人工植被土壤水分状况

open access: yesShuitu Baochi Xuebao, 2008
采用烘干法及WP4水势仪对黄土高原水蚀风蚀复合区人工林下土壤重量含水量及水势进行测定,从土壤水分数量和能量两方面分析该区土壤水分时空分布和动态变化特征,并且通过实测数据对不同树种土壤水分特征曲线进行拟合,旨在为该区今后植被建设及生态用水提供理论参考。结果表明,各树种在0-300 cm土层土壤含水量随深度增加而逐渐降低,并趋于稳定。0-30 cm土层土壤含水量变化剧烈,30 cm以下土层土壤含水量逐渐降低,并趋于稳定在3.00%~5.00%。土壤水分受降雨量及其分配影响显著,观测期内土壤储水量盈余26.7
周海光   +4 more
doaj  

From Dendrite Accelerator to Suppressor: Engineering a Self‐Assembled Monolayer for Ultrafast and Dendrite‐Free Zinc Deposition

open access: yesRare Metals, Volume 45, Issue 5, May 2026.
ABSTRACT Aqueous zinc‐ion batteries are plagued by anode challenges such as dendrite growth and corrosion, which stem from intrinsic surface heterogeneity. Although constructing a homogeneous interfacial layer is a promising strategy, conventional electrolyte additives often suffer from incomplete or unstable coverage.
Ke Huang   +6 more
wiley   +1 more source

电解质脉冲法测量水流流速和泥沙含量的方法

open access: yes, 2002
本发明公开了一种电解质脉冲法测量水流流速和泥沙含量的方法,以溶质运移理论、波动学、传导学为基础,结合现代数学建立并求解电解质脉冲在含沙径流中的运移模型,分析模型中水流速度和泥沙含量的特征量,并以理论依据的计算和数据存贮,制作通过水流和泥沙含量测试的计算机软件,本发明能很好地同时测量水流流速和泥沙含量,测量精度非常高,速度较快,并且简单易用。本发明可应用于各种导电性能不太好液体的流速和其中悬浮质的含量测量,测量速度范围为大于零、小于50m/s。泥沙含量测量范围为0-100%,因此也可以测量土壤 ...
王辉, 雷廷武, 赵军, 夏卫生
core  

粗质地土壤坡度和前期含水量对土壤侵蚀的影响

open access: yes, 2017
利用野外模拟降雨试验,研究了粗质地土壤裸地和苜蓿地在不同坡度( 5° , 15° , 25° )、不同前期含水量 (低、中、高)条件下坡面降雨产流、产沙的过程及其特征,以此探究该区退耕还草效益。结果表明: 3 种坡度 条件下裸地和苜蓿地的产流过程在不同前期含水量下均为先增大后趋于稳定,不同坡度之间的径流量差 异不显著,但泥沙流失量随着坡度的增大而显著增加,在降雨过程中先增大达到峰值趋于稳定波动,裸地 的波动幅度大于苜蓿地。 2 ...
游微, 樊军
core   +1 more source

基于时域介电法的绝缘纸板水分特征量研究

open access: yesGaoya dianqi, 2018
为了评估变压器绝缘纸板的含水量,从而为现场变压器绝缘状态和寿命估计提供可靠指导,笔者在实验室环境中制备4组不同含水量的油纸绝缘试样,采用极化/去极化电流法(PDC)对不同水分含量绝缘纸板开展了研究,提出了可表征纸板含水量的特征量Qpaper。实验结果表明,PDC曲线对油纸绝缘试样含水量的变化十分敏感,且水分含量的改变对于去极化电流曲线的尾端有很大影响;通过去极化电流曲线可以获得拓展Debye模型的各支路参数,且随着水分含量的增加模型支路数量在增加,最大支路时间常数在变大 ...
夏国强, 吴广宁, 宋臻杰, 高波
doaj  

Thermally Driven Hydrogenation of CO2 to Light Olefins Over Hollow Cubic In2O3‐La‐ZIF‐8 Tandem Catalyst

open access: yesRare Metals, Volume 45, Issue 4, April 2026.
ABSTRACT Thermally driven hydrogenation of CO2 to light olefins (C2=–C4=) using metal oxide‐zeolite tandem catalysts is an effective strategy for achieving carbon neutrality. However, progress in this area is constrained by zeolite pore transport limitations, acid‐site inactivation, and surface carbon poisoning.
Haifeng Tian   +10 more
wiley   +1 more source

灌水量对大麦籽粒蛋白质及其组分含量的影响

open access: yes, 2007
研究在大田条件下灌水量对大麦籽粒蛋白质及其组分含量的影响。结果表明:不同灌水量对大麦籽粒蛋白质性状的效应不明显;品种与灌水量的互作对大麦籽粒醇溶蛋白的作用达到显著水平;不同品种间在蛋白质及其各组分含量上均有不同程度的差异。说明大麦籽粒蛋白质性状的水分生理不敏感 ...
靳正忠   +3 more
core  

Comparative Evaluation of Chemical and Physical Expansive Agents in Cemented Paste Backfill: Expansion Behavior, Mechanical Response, and Microstructural Mechanisms

open access: yesRare Metals, Volume 45, Issue 4, April 2026.
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

基于回复电压法的变压器绝缘纸水分及绝缘状态研究

open access: yesGaoya dianqi, 2017
变压器绝缘纸中水分会加速油纸绝缘的老化,缩短变压器寿命,因此,准确诊断变压器绝缘纸老化状态以及水分含量对变压器安全运行具有重要意义。文中通过测试分析不同水分、不同聚合度的绝缘油纸回复电压曲线,研究发现当绝缘纸处于低水分含量状态(0.5 ...
尹小兵   +5 more
doaj  

Elevation, soil pH and calcium availability shape regional and local scale spatial patterns of PhoD gene abundance in tropical and subtropical forests

open access: yesFunctional Ecology, Volume 40, Issue 4, Page 983-1000, April 2026.
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

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