Results 41 to 50 of about 1,038,648 (163)

Root exudates mediate microorganisms to improve rhizosphere nutrient availability and crop productivity under straw mulching and slow‐release nitrogen fertilizer

open access: yesFunctional Ecology, Volume 40, Issue 6, Page 1725-1739, June 2026.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Root exudates play a key role as signals and nutrients in mediating plant–microbe communication. However, critical knowledge gaps remain regarding how root exudates mediate soil–microbe–plant interactions to regulate crop yield under long‐term straw mulching combined ...
Jiajie Song   +7 more
wiley   +1 more source

爆炸-强夯联合加密饱和砂基的工程实践

open access: yes, 1997
爆炸加密饱和砂是近年来码头建设中采用的一种新方法,加密深层饱和砂效果尤为明显;强夯法是传统的加密松散介质方法,但其有效影响深度一般不超过6m。通过试验,将两种方法结合起来用于加密陆域推填的饱和砂层取得了很好的效果。本文结合南方某电厂陆域推填饱和砂的加密工程,介绍了这一新工艺的施工方法及检测结果 ...
燕琳, 张加华, 李世海
core  

Global overview of progress in respecting the contributions of traditional knowledge in biodiversity governance

open access: yesConservation Biology, Volume 40, Issue 3, June 2026.
Abstract Recognition and engagement of Indigenous Peoples and local communities (IP&LCs) and other traditional knowledge (TK) holders in formal biodiversity governance remain limited, despite their significant contribution to the conservation and sustainable use of biodiversity through their knowledge, innovations, practices, and land stewardship.
Kinga Öllerer   +8 more
wiley   +1 more source

加权质心法亚像元定位误差研究

open access: yes, 2011
加权质心法常用于CCD星敏感器或自准直仪的亚像元定位细分 过程,它直接影响着系统的定位精度,因此对加权质心法的误差分析有着极重要的意义。从质心法原理出发,详细分析了误差产生的原因,并推导出了质心法和加权 质心法的误差计算公式。然后以点斑为例,对其系统误差和随机误差进行了定量分析和比较。分析证明,光斑大小对于系统的测量精度有着重要的影响,合理对光斑 ...
李朋, 刘爱敏, 吴易明, 高立民
core  

基于WSAM的滚动轴承故障IAS信号特征提取

open access: yesZhendong Ceshi yu Zhenduan
将谱幅值调制(spectral amplitude modulation,简称SAM)技术与编码器信号相结合,提出一种基于加权谱幅值调制(weight spectral amplitude modulation,简称WSAM)的滚动轴承故障瞬时角速度(instantaneous angular speed,简称IAS)信号特征提取方法。首先,采用前向差分法对编码器信号进行处理,将得到的IAS信号进行傅里叶变换(Fourier transform,简称FT),得到幅值和相位,保持相位不变 ...
doaj   +1 more source

Strong laws of large numbers of weighed sums of B-valued exchangeable random variables(B值可交换变量加权和的强大数律)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2008
给出了B值可交换随机变量的加权和在一定条件下的几个强大数定理,从而推广了Marcinkiewicz强大数律.
SHENYan-feng(沈炎峰)
doaj   +1 more source

Geographic risks to functional groups of mammals and birds from habitat loss in Mexico

open access: yesConservation Biology, Volume 40, Issue 3, June 2026.
Abstract There is a need to quantify the impact of habitat loss due to anthropogenic factors on different aspects of biodiversity, such as functional trait diversity represented by functional groups (FGs). We developed a metric to assess the weighted risk of loss of habitat for 33 FGs of mammals and 36 FGs of birds in Mexico based on potential ...
Fernando Mayani‐Parás   +4 more
wiley   +1 more source

一种用于过滤和洗涤样品的自动添加液体的装置

open access: yes, 2007
一种用于过滤和洗涤样品的自动添加液体的装置,包括:一容置液体的储液器,其顶部设有进液口,底部设有出液口;一出液控制阀,连接于储液器的出液口与液体分散器之间,用以控制流向液体分散器的液流的通断;一温度传感器,安装在储液器中,用以测量储液器中液体的温度;一加热器,安装在储液器上,用以加热储液器中的液体;一液位传感器,安装在液体分散器的一侧,用于测量液体分散器流出液体的液位高度;一电源控制箱,与上述出液控制阀、温度传感器、加热器以及液位传器各部件电性连接,分别控制各部件的工作状态。本发明结构简单,易扩展应用 ...
孙公权, 唐水花, 秦 兵, 辛 勤
core  

现代企业制度改革中产权理论的若干问题 [PDF]

open access: yes, 1995
现代企业制度改革中产权理论的若干问题厦门大学财金系庄志加产权明晰和产权的可交易性是现代企业制度改革的本质特征。国有企业改革就是国有产权管理体制的改革,如何提高国有资产运营效率,首先应明确产权理论的几个认识问题。一、统一“产权”含义的认识目前,理论界对..
庄志加
core  

幅席加权的等间隔交替抽样理论

open access: yes四川大学学报. 自然科学版, 1979
本文用抽样理论证实了在声孔径加权的声表面波叉指换能器中指条极性的放置原理;换能器的指条极性主要取决于加权函数的形式。根据本文所证明的理论,抽样指条的极性必须在加权函数过零点处倒相放置。最后对单指和分裂指换能器给出了按抽样规定的指条极性在工艺上的设计公式。
刘永澄, 张育才, 王永德
doaj  

Home - About - Disclaimer - Privacy