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Proposed Wave Momentum Source for Generating the 22-Year Solar Cycle
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作者 Hans G. Mayr 《International Journal of Astronomy and Astrophysics》 2023年第2期74-88,共15页
For the 22-year solar cycle oscillation there is no external time dependent source. A nonlinear oscillation, the solar cycle must be generated internally, and Babcock-Leighton models apply an artificial nonlinear sour... For the 22-year solar cycle oscillation there is no external time dependent source. A nonlinear oscillation, the solar cycle must be generated internally, and Babcock-Leighton models apply an artificial nonlinear source term that can simulate the observations—which leaves open the question of the actual source mechanism for the solar cycle. Addressing this question, we propose to take guidance from the wave mechanism that generates the 2-year Quasi-biennial Oscillation (QBO) in the Earth atmosphere. Upward propagating gravity waves, eastward and westward, deposit momentum to generate the observed zonal wind oscillation. On the Sun, helioseismology has provided a thorough understanding of the acoustic p-waves, which propagate down into the convective envelope guided by the increasing temperature and related propagation velocity. Near the tachocline with low turbulent viscosity, the waves propagating eastward and westward can produce an axisymmetric 22-year oscillation of the zonal flow velocities that can generate the magnetic solar dynamo. Following the Earth model, waves in opposite directions can generate in the Sun wind and magnetic field oscillations in opposite directions, the proposition of a potential solar cycle mechanism. 展开更多
关键词 Dynamo Models Apply Artificial Nonlinearity Wave Generated Nonlinear Terrestrial 2-Year Oscillation Model-Analogue Example Helioseismology Wave source Proposed for Solar Cycle Mechanism
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A Comparative Study of Williamson Hybrid Nanofluid Flow Consisting of Cu, GaN, and Al2O3 Nanoparticles in Ethylene Glycol over a Stretching Sheet with Suction/Injection and Heat Source/Sink
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作者 Mamidala Jyotshna Vadlakonda Dhanalaxmi 《Journal of Applied Mathematics and Physics》 2022年第12期3864-3897,共34页
Several new techniques in the field of heat transfer in fluids have opened new avenues for studying the heat transfer effects in nanofluids and thermodynamic flow parameters, leading to novel applications. There have ... Several new techniques in the field of heat transfer in fluids have opened new avenues for studying the heat transfer effects in nanofluids and thermodynamic flow parameters, leading to novel applications. There have been studies on nanofluids, including metal, ceramic and magnetic nanoparticles mixed with base fluids such as Water, Kerosene, and Ethylene glycol. However, research on fluids employing semiconductor nanoparticles as supplements to base fluids to generate nanofluids and hybrid nanofluids is limited. For the investigation, Gallium nitrite, a binary semiconductor with excellent heat convection, is together with Cu metal nanoparticles and Al<sub>2</sub>O<sub>3</sub> ceramic nanoparticles separately in the base fluid Ethylene glycol (EG) to form hybrid nanofluids. The effects of convective boundary conditions, thermal radiation, heat source/sink, suction/injection, and activation energy on three-dimensional Williamson MHD hybrid nanofluid flow of Cu + GaN + EG, Al<sub>2</sub>O<sub>3</sub> + GaN + EG, and Cu + Al<sub>2</sub>O<sub>3</sub> + EG are investigated on a stretched sheet with porosity. A similarity transformation is performed on the governing equations to transform them into dimensionless ordinary differential equations ODEs. Numerical analysis is carried out in MATLAB utilizing bvp5c and the shooting technique. The variations of velocity, temperature, and concentration profiles as a function of different physical effects are presented graphically with dimensionless parameters and explained the variations scientifically. As varied with different parameters, the values of the Skin-friction coefficient, Nusselt number, and Sherwood number are mentioned in the table. 展开更多
关键词 Williamson Hybrid Nanofluid Gallium Nitride Heat Transfer Heat source/sink Suction/Injection Solid Volume Fraction
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渤海湾盆地南堡凹陷2号构造带油气地球化学特征与来源 被引量:1
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作者 刘华 魏鑫 +4 位作者 欧阳冠宇 刘景东 陈蕾 刘海青 孟祥雨 《中国海上油气》 CAS CSCD 北大核心 2024年第1期26-36,共11页
渤海湾盆地南堡凹陷2号构造带具有多洼、多层系供烃的特征。为了揭示其复杂的油气来源,开展色谱-质谱等地化测试,分析原油地化特征,将原油分为3类,并确定每类原油的来源。结果表明:(1)Ⅰ类原油主要分布于西构造带沙三段储层中,原油中C27... 渤海湾盆地南堡凹陷2号构造带具有多洼、多层系供烃的特征。为了揭示其复杂的油气来源,开展色谱-质谱等地化测试,分析原油地化特征,将原油分为3类,并确定每类原油的来源。结果表明:(1)Ⅰ类原油主要分布于西构造带沙三段储层中,原油中C27与C29规则甾烷相对含量接近,孕甾烷参数((孕甾烷+升孕甾烷)/规则甾烷)和甾烷异构化参数(C29甾烷20S/(20R+20S)、C29甾烷ββ/(αα+ββ))较高,具有水生生物和高等植物共同输入特征,原油成熟度高,来源于沙三段烃源岩;(2)Ⅱ类原油主要分布于西构造带东二段储层中,原油中C29规则甾烷含量具明显优势,孕甾烷参数和甾烷异构化参数均低,原油母质中高等植物具有明显优势,原油成熟度整体偏低,来源于沙一段—东三段烃源岩;(3)Ⅲ类原油主要分布于东构造带东三段和西构造带东一段和明化镇组储层中,原油中C29规则甾烷具有一定优势,孕甾烷参数较低,甾烷异构化参数较高,以高等植物输入为主,原油成熟度较高,为3套烃源岩的混合来源;(4)原油4-/1-MDBT和Ts/Tm指数具有沿断层向浅部层系减小的趋势,且原油甲基菲换算的镜质体反射率与下覆烃源岩镜质体反射率一致,表明研究区原油具有原地供烃的特点。本研究成果为研究区的浅层精细勘探及深层勘探提供理论指导。 展开更多
关键词 渤海湾盆地 南堡凹陷 2号构造带 原油类型 地化特征 生物标志化合物 油源对比 原地供烃
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Assessing effects of “source-sink” landscape on non-point source pollution based on cell units of a small agricultural catchment 被引量:4
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作者 WANG Jin-liang CHEN Cheng-long +4 位作者 NI Jiu-pai XIE De-ti GUO Xi LUO Zhi-jun ZHAO Yue 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2048-2062,共15页
Ascertaining the relationship between "source-sink" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To ... Ascertaining the relationship between "source-sink" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To reveal the relationships between "sourcesink" landscape and NPS pollution based on cell units of a small catchment in the Three Gorges Reservoir Region(TGRR), the runoff and nutrient yields were simulated first by rainfall events on a cell unit scale based on the Annualized AGricultural Non-Point Source Pollution Model(AnnAGNPS). Landscape structure and pattern were quantified with "sourcesink" landscape indicators based on cell units including landscape area indices and locationweighted landscape indices. The results showed that:the study case of small Wangjiagou catchment highlighted a good prediction capability of runoff and nutrient export by the AnnAGNPS model. Throughout the catchment, the spatial distribution trends of four location-weighted landscape indices were similar to the trends of simulated total nitrogen(TN) and total phosphorus(TP), which highlighted the importance of spatial arrangement of "source" and "sink" landscape types in a catchment when estimating pollutant loads. Results by Pearson correlation analysis indicated that the location-weighted landscape index provided a more comprehensive account of multiple factors, and can better reflect NPS-related nutrient loss than other landscape indices applied in single-factor analysis. This study provides new findings for applying the "source-sink" landscape indices based on cell units in small catchments to explain the effect of "source-sink" landscape on nutrient export based on cell unit, and helps improve the understanding of the correlation between "source-sink" landscape and NPS pollution. 展开更多
关键词 Nutrient load Non-point source pollution source sink LANDSCAPE index SMALL catchment
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Genetic bases of source-,sink-,and yield-related traits revealed by genome-wide association study in Xian rice 被引量:10
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作者 Yun Wang Yunlong Pang +4 位作者 Kai Chen Laiyuan Zhai Congcong Shen Shu Wang Jianlong Xu 《The Crop Journal》 SCIE CAS CSCD 2020年第1期119-131,共13页
The source-sink relationship determines the ultimate grain yield.We investigated the genetic basis of the relationship between source and sink and yield potential in rice.In two environments,we identified quantitative... The source-sink relationship determines the ultimate grain yield.We investigated the genetic basis of the relationship between source and sink and yield potential in rice.In two environments,we identified quantitative trait loci(QTL)associated with sink capacity(total spikelet number per panicle and thousand-grain weight),source leaf(flag leaf length,flag leaf width and flag leaf area),source-sink relationship(total spikelet number to flag leaf area ratio)and yield-related traits(filled grain number per panicle,panicle number per plant,grain yield per plant,biomass per plant,and harvest index)by genome-wide association analysis using 272 Xian(indica)accessions.The panel showed substantial variation for all traits in the two environments and revealed complex phenotypic correlations.A total of 70 QTL influencing the 11 traits were identified using 469,377 high-quality SNP markers.Five QTL were detected consistently in four chromosomal regions in both environments.Five QTL clusters simultaneously affected source,sink,source–sink relationship,and grain yield traits,probably explaining the genetic basis of significant correlations of grain yield with source and sink traits.We selected 24 candidate genes in the four consistent QTL regions by identifying linkage disequilibrium(LD)blocks associated with significant SNPs and performing haplotype analysis.The genes included one cloned gene(NOG1)and three newly identified QTL(qHI6,qTGW7,and qFLA8).These results provide a theoretical basis for high-yield rice breeding by increasing and balancing source–sink relationships using marker-assisted selection. 展开更多
关键词 RICE GWAS sourcesink relationship Quantitative trait loci/locus(QTL) Candidate gene
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Diagnostic Study of Apparent Heat Sources and Moisture Sinks in the South China Sea and its Adjacent Areas during the Onset of 1998 SCS Monsoon 被引量:7
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作者 王世玉 钱永甫 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第2期285-298,共14页
The apparent heat sources (?Q1 ?) and moisture sinks (?Q2 ?) are calculated based on the reanalyzed data of the South China Sea Monsoon Experiment (SCSMEX) from May 1 to August 31, 1998. It is found that the formation... The apparent heat sources (?Q1 ?) and moisture sinks (?Q2 ?) are calculated based on the reanalyzed data of the South China Sea Monsoon Experiment (SCSMEX) from May 1 to August 31, 1998. It is found that the formation and distribution of the atmospheric heat sources are important for the monsoon onset. The earlier onset of the SCS monsoon is the result of enduring atmospheric heating in the Indo–China Peninsula and South China areas. The atmospheric heating firstly appears in the Indo–China Peninsula area and the sensible heat is the major one. The 30–50 day periodic oscillation of atmospheric heat sources between the SCS area and the western Pacific warm pool has a reverse phase distribution before the middle of July and the low frequency oscillation of heat sources in SCS area has an obvious longitudinal propagation. The 30–50 day low frequency oscillation has vital modificatory effects on the summer monsoon evolution during 1998. Key words Apparent heat sources - Apparent moisture sinks - The South China Sea monsoon - Diagnostic Study Sponsored by the National Key Project of Fundamental Research “ SCSMEX” and the Research Fund for the Doctoral Program of Higher Education: “ Study of the Air-sea Interaction in the SCS Monsoon Region”. 展开更多
关键词 Apparent heat sources Apparent moisture sinks The South China Sea monsoon Diagnostic Study
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Source-Sink Relationship in Intersubspecific Hybrid Rice 被引量:2
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作者 LI Ji-hang XIANG Xun-chao +1 位作者 HE Li-bin LI Ping 《Rice science》 SCIE 2006年第4期250-256,共7页
Three indica restorer lines (Mianhui 725, Shuhui 527, Shuhui 881), an American rice variety Lemont and a javanica rice variety Xiangdali were crossed with japonica Kitaake, and five F1 hybrids were obtained to study... Three indica restorer lines (Mianhui 725, Shuhui 527, Shuhui 881), an American rice variety Lemont and a javanica rice variety Xiangdali were crossed with japonica Kitaake, and five F1 hybrids were obtained to study the photosynthetic and agronomic traits. The data on photosynthetic characteristics indicated that the net photosynthetic rate (Pn) of the five F1 hybrids was significantly higher than that of their parents (or one of them) under high photosynthetic flux density (PFD); while the overall performance of hybrids was better than their respective parents in apparent quantum yield (AQY), carboxylation efficiency (CE) and CO2 compensation point (CCP). Moreover, the photosynthetic performance of the five F1 were different due to the variation in heredity and the typical indica-japonica hybrids, Mianhui 725/Kitaake and Shuhui 527/Kitaake, were better than the others on this aspect. The agronomic traits revealed that the five F1 exhibited different heterosis, with Shuhui 881/Kitaake the largest sink followed by Mianhui 725/Kitaake, Shuhui 527/Kitaake, Lemont/Kitaake and Xiangdali/Kitaake. The production potential of indica-japonica hybrids was higher than that of the other two hybrids, which was consistent with the performance of Pn. However, the superior trait of indica-japonica hybrids on sink size has not been fully turned into high yield because of abnormal seed setting. Therefore, attention should be paid to the proper genome coordination and appropriate genetic distance so as to achieve super high yielding. 展开更多
关键词 RICE intersubspecific hybrid source sink net photosynthetic rate genetic distance HETEROSIS
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Ecosystem carbon storage and sink/source of temperate forested wetlands in Xiaoxing’anling, northeast China 被引量:4
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作者 Biao Wang Changcheng Mu +3 位作者 Huicui Lu Na Li Yan Zhang Li Ma 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期839-849,共11页
Wetlands play an important role in the global carbon cycle, but there are still considerable uncertainties in the estimation of wetland carbon storage and a dispute on whether wetlands are carbon sources or carbon sin... Wetlands play an important role in the global carbon cycle, but there are still considerable uncertainties in the estimation of wetland carbon storage and a dispute on whether wetlands are carbon sources or carbon sinks. Xiaoxing’anling are one of several concentrated distribution areas of forested wetland in China, but the carbon storage and carbon sink/source of forested wetlands in this area is unclear. We measured the ecosystem carbon storage (vegetation and soil), annual net carbon sequestration of vegetation and annual carbon emissions of soil heterotrophic respiration of five typical forested wetland types (alder swamp, white birch swamp, larch swamp, larch fen, and larch bog) distributed along a moisture gradient in this area in order to reveal the spatial variations of their carbon storage and quantitatively evaluate their position as carbon sink or source according to the net carbon balance of the ecosystems. The results show that the larch fen had high carbon storage (448.8 t ha^(−1)) (6.8% higher than the larch bog and 10.5–30.1% significantly higher than other three wetlands (P < 0.05), the white birch swamp and larch bog were medium carbon storage ecosystems (406.3 and 420.1 t ha^(−1)) (12.4–21.8% significantly higher than the other two types (P < 0.0 5), while the alder swamp and larch swamp were low in carbon storage (345.0 and 361.5 t ha^(−1), respectively). The carbon pools of the five wetlands were dominated by their soil carbon pools (88.5–94.5%), and the vegetation carbon pool was secondary (5.5–11.5%). At the same time, their ecosystem net carbon balances were positive (0.1–0.6 t ha^(−1) a^(−1)) because the annual net carbon sequestration of vegetation (4.0–4.5 t ha^(−1) a^(−1)) were higher than the annual carbon emissions of soil heterotrophic respiration (CO_(2) and CH_(4)) (3.8–4.4 t ha^(−1) a^(−1)) in four wetlands, (the alder swamp being the exception), so all four were carbon sinks while only the alder swamp was a source of carbon emissions (− 2.1 t ha^(−1) a^(−1)) due to a degraded tree layer. Our results demonstrate that these forested wetlands were generally carbon sinks in the Xiaoxing’anling, and there was obvious spatial variation in carbon storage of ecosystems along the moisture gradient. 展开更多
关键词 Temperate forested wetlands Ecosystem carbon storage Carbon sink or source Xiaoxing’anling of China
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Convection of Maxwell fluid over stretching porous surface with heat source/sink in presence of nanoparticles:Lie group analysis 被引量:1
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作者 Limei CAO Xinhui SI Liancun ZHENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第4期433-442,共10页
The convection of a Maxwell fluid over a stretching porous surface with a heat source/sink in the presence of nanoparticles is investigated. The Lie symmetry group transformations are used to convert the boundary laye... The convection of a Maxwell fluid over a stretching porous surface with a heat source/sink in the presence of nanoparticles is investigated. The Lie symmetry group transformations are used to convert the boundary layer equations into coupled nonlinear ordinary differential equations. The ordinary differential equations are solved numerically by the Bvp4c with MATLAB, which is a collocation method equivalent to the fourth-order mono-implicit Runge-Kutta method. Furthermore, more attention is paid to the effects of the physical parameters, especially the parameters related to nanoparticles, on the temperature and concentration distributions with consideration of permeability and the heat source/sink. 展开更多
关键词 Lie group Maxwell fluid porous stretching surface heat sink or source
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Mixed convection flow in vertical channel with boundary conditions of third kind in presence of heat source/sink 被引量:1
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作者 J.C.UMAVATHI J.PRATHAP KUMAR JAWERIYA SULTANA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第8期1015-1034,共20页
The effects of viscous dissipation and heat source/sink on fully developed mixed convection for the laminar flow in a parallel-plate vertical channel are investigated. The plate exchanges heat with an external fluid. ... The effects of viscous dissipation and heat source/sink on fully developed mixed convection for the laminar flow in a parallel-plate vertical channel are investigated. The plate exchanges heat with an external fluid. Both conditions of equal and different reference temperatures of the external fluid are considered. First, the simple cases of the negligible Brinkman number or the negligible Grashof number are solved analytically. Then, the combined effects of buoyancy forces and viscous dissipation in the presence of heat source/sink are analyzed by a perturbation series method valid for small values of the perturbation parameter. To relax the conditions on the perturbation parameter, the velocity and temperature fields are solved by using the Runge-Kutta fourth-order method with the shooting technique. The velocity, temperature, skin friction, and Nusselt num- bers at the plates are discussed numerically and presented through graphs. 展开更多
关键词 mixed convection viscous fluid perturbation method Runge-Kuttashooting method heat source/sink
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Reassessment of the Distribution of Mantle CO_(2) in the Bohai Sea,China:The Perspective from the Source and Pathway System 被引量:3
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作者 TANG Huafeng GUO Tianchan +4 位作者 WU Keqiang LIU Zilin XU Jianyong LU Baoliang WANG Pujun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第1期337-347,共11页
Research on the distribution of mantle CO_(2)should involve comprehensive analysis from CO_(2)source to accumulation.The crust-mantle pathway system is the key controlling factor of the distribution of mantle CO_(2),b... Research on the distribution of mantle CO_(2)should involve comprehensive analysis from CO_(2)source to accumulation.The crust-mantle pathway system is the key controlling factor of the distribution of mantle CO_(2),but has received little attention.The pathway system and controlling factors of CO_(2)distribution in the Bohai Sea are analyzed using data on fault styles and information on the mantle and lithosphere.The relation between volcanic rocks and the distribution of mantle CO_(2)is reassessed using age data for CO_(2)accumulations.The distribution of mantle CO_(2)is controlled by uplift of the asthenosphere and upper mantle,magma conduits in the mantle and fault systems in the crust.Uplifted regions of the asthenosphere are accumulation areas for CO_(2).The area with uplift of the Moho exhibits accumulation of mantle CO_(2)at depth.CO_(2)was mainly derived from vertical migration through the upper mantle and lower crust.The fault style in the upper crust controls the distance of horizontal migration and the locations of CO_(2)concentrations.The distribution of mantle CO_(2)and volcanic rocks are not the same,but both probably followed the same pathways sometimes.Mantle CO_(2)in the Bohai Sea is concentrated in the Bozhong sag and the surrounding area,particularly in a trap that formed before 5.1 Ma and is connected to crustal faults(the Bozhang faults)and lithospheric faults(the Tanlu faults). 展开更多
关键词 mantle CO_(2) source area pathway system fault MOHO Bohai Sea
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A Review of Comminution Age Method and Its Potential Application in the East China Sea to Constrain the Time Scale of Sediment Source-to-Sink Process 被引量:5
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作者 LI Chao YANG Shouye +2 位作者 LIAN Ergang BI Lei ZHANG Zhaofeng 《Journal of Ocean University of China》 SCIE CAS 2015年第3期399-406,共8页
The East China Sea(ECS) is a river-dominated epicontinental sea, linking the Asian continent to the northwestern Pacific via the large rivers originating from Tibetan Plateau. The relevant huge influx of riverine detr... The East China Sea(ECS) is a river-dominated epicontinental sea, linking the Asian continent to the northwestern Pacific via the large rivers originating from Tibetan Plateau. The relevant huge influx of riverine detritus has developed unique sedimentary systems in the ECS during the Quaternary, offering ideal terrestrial archives for reconstructing Quaternary paleoenvironmental changes and studying land-sea interactions. Overall, two characteristic river systems dominate the sedimentary systems and sediment source to sink transport patterns in the ECS, represented by the Changjiang(Yangtze River) and Huanghe(Yellow River) for the large river system and Taiwan rivers for the small river system. Given this, the sediments derived from both river systems bear distinct features in terms of parent rock lithology, provenance weathering and sediment transport. Previous studies mostly focus on either the ‘source' discrimination or the ‘sink' records of the sedimentary system in the ECS, while the source to sink process linking the land and sea, in particular its time scale, has been poorly understood. Here we introduce a newly-developed dating technique, the ‘comminution age' method, which offers a quantitative constraint on the time scale of sediment transfer from its ultimate source to the final depositional sink. This novel method is of great significance for improving our understanding on the earth surface processes including tectonic-climate driven weathering, and sediment recycling in relation to landscape evolution and marine environmental changes. The application of comminution age method in the ECS will provide important constraints on sediment source-to-sink process and more evidences for the construction of late Quaternary paleoenvironmental changes under these unique sedimentary systems. 展开更多
关键词 时间尺度 东中国海 应用程序 接收器 粉碎 进程 年龄 沉积物源
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基于有约束L_(1/2)范数稀疏正则化的声源识别方法
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作者 潘薇 李远文 +1 位作者 冯道方 黎敏 《振动与冲击》 EI CSCD 北大核心 2024年第2期166-178,共13页
基于等效源法(equivalent source method,ESM)的近场声全息(near field acoustic holography,NAH)是一种有效的声源识别技术。然而,针对空间稀疏分布的声源识别问题,传统基于L_(2)范数以及基于L_(1)范数的ESM方法分别存在声源幅值被低... 基于等效源法(equivalent source method,ESM)的近场声全息(near field acoustic holography,NAH)是一种有效的声源识别技术。然而,针对空间稀疏分布的声源识别问题,传统基于L_(2)范数以及基于L_(1)范数的ESM方法分别存在声源幅值被低估与算法稳定性差等问题。因此,提出了基于有约束L_(1/2)范数稀疏正则化的声源识别方法,该方法具有强稀疏性与强抗干扰的优势,可以解决传统方法的声源识别精度低的问题。通过数值模拟试验以及普通室内的实测实验,验证了方法的有效性。 展开更多
关键词 声源识别 等效源法(ESM) 有约束L_(1/2)范数 稀疏正则化
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Source-Sink and Grain-Filling Characteristics of Two-Line Hybrid Rice Yangliangyou 6 被引量:6
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作者 ZHAO Bu-hong WANG Peng +2 位作者 ZHANG Hong-xi ZHU Qing-sen YANG Jian-chang 《Rice science》 SCIE 2006年第1期34-42,共9页
With two-line hybrid rice Yangliangyou 6 (YLY6) and Liangyoupeijiu (LYPJ) and three-line hybrid rice Shanyou 63 (SY63) as materials, the source, sink and flow characteristics in association with grain filling we... With two-line hybrid rice Yangliangyou 6 (YLY6) and Liangyoupeijiu (LYPJ) and three-line hybrid rice Shanyou 63 (SY63) as materials, the source, sink and flow characteristics in association with grain filling were investigated. The seed-setting rate, grain filling degree and grain yield of YLY6 and SY63 were significantly higher than those of LYPJ. The export and transformation percentages of the matter in culms and sheaths of YLY6 and SY63 were significantly higher than those of LYPJ. Activities of sucrose synthase, adenosine diphosphoglucose pyrophosphorylase, starch synthase and starch branching enzyme in grains were higher for YLY6 and SY63 than for LYPJ, and were very significantly correlated with maximum grain filling rate, mean grain filling rate, grain filling degree and grain weight. The spikelet number, grain yield and total sink load per area of vascular bundle and phloem of YLY6 and SY63 were significantly smaller than those of LYPJ, and the greater the load, the lower seed-setting rate and the poorer grain filling. The transportation rate per area phloem of YLY6 was greater than that of LYPJ or SY63. The results suggest that YLY6 possesses strong source, great sink activity and efficient flow, which lay a physiological base for its high seed-setting rate and good grain filling. 展开更多
关键词 hybrid rice source-sink characteristics grain filling enzyme activity
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Discussion on Role of Forest to Control Agricultural Non-Point Source Pollution in Taihu Lake Basin-Based on Source-Sink Analysis 被引量:5
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作者 Jianfeng ZHANG Jingmin JIANG +6 位作者 Zhijian ZHANG Qihua SHAN Guangcai CHEN Ying WANG Yonghui XU Harry WU Aljoy ABARQUEZ 《Journal of Water Resource and Protection》 2009年第5期345-350,共6页
Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, J... Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, Ji-angsu and Zhejiang. The pollutants originate mainly from acidy rain, home sewage of the vast number of inhabitants, livestock manure, agricultural fertilizers & pesticides applied over fields in the drainage basin, and the industrial sewage. Due to the kinds of pollutants, the Lake water is getting highly eutrophic, with frequent blooms of blue-green algae. Compared with point-source pollutants, diffuse pollution is much com-plicated and difficult to control. Thus combating non-point pollution (NPP) is paid much great attention. Based on analysis on source-sink of NPP in Taihu Lake basin, it is concluded that the function of forests on NPP control is multiple and important by both source reduction and sink expansion. The primary objective of planting trees through constructing forested wetlands and establishing riparian forest buffers is to control soil & water erosion, decrease agrochemicals application, and improve farming conditions in the region of Taihu Lake basin. Moreover forests help to intercept acidy rain, protect streambanks, uptake nutrients, hold up pollutants and provide habitat for wildlife. 展开更多
关键词 Non-Point source POLLUTION RIPARIAN FOREST BUFFER Zone source-sink Taihu LAKE
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Source-sink Characteristics and the Translocation of Assi- milates in New Plant Type and Intersubspecific Hybrid Rice 被引量:5
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作者 YANG Jian-chang, ZHANG Wen-hu, WANG Zhi-qin, LIU Li-jun and ZHU Qing-sen( Key Laboratory of Crop Cultivation and Physiology, MOA , Yangzhou University, Yangzhou 225009) 《Agricultural Sciences in China》 CAS CSCD 2002年第2期155-162,共8页
Both new plant type (NPT) and intersubspecific hybrid rice (IHR) had large sink size (total number of spikelets per m2), however, poor grain filling limited their potential in the grain yield. Compared to the three-li... Both new plant type (NPT) and intersubspecific hybrid rice (IHR) had large sink size (total number of spikelets per m2), however, poor grain filling limited their potential in the grain yield. Compared to the three-line indica hybrid of Shanyou 63 (CK), NPT and IHR showed higher photosynthetic potential, higher dry matter accumulation and higher ratio of dry weight to spikelets (total dry wt./total number of spikelets) from heading to harvest. But both exhibited a low export percentage and transfer ratio of assimilates, low partitioning of 14C to grains from labeled flag leaves, low harvest indices and low physiological activities (IAA content and activities of ATPase and starch synthase) of grains at early grain-filling stage. The physiological activities of grains at early filling stage were significantly correlated with the export percentage and transfer ratio of assimilates, ripened-grain percentage and grain plumpness (r = 0.85 - 0.95). The source-sink ratio (dry matter wt./spikelet and nonstructural carbohydrate/spikelet) at heading was positively correlated with physiological activities of grains (r = 0. 84 - 0. 97 ). It is suggested that low physiological activities of grains at early filling stage is attributed to low source-sink ratio at heading, and the low sink activity weakens the ability to remobilize assimilates into grains, and leads to poor grain filling in NPT and IHR. 展开更多
关键词 RICE New plant type Intersubspecifiic hybrid source-sink Assimilate translocation
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Source-sink landscape spatial characteristics and effect on non-point source pollution in a small catchment of the Three Gorge Reservoir Region 被引量:8
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作者 WANG Jin-liang NI Jiu-pai +4 位作者 CHEN Cheng-long XIE De-ti SHAO Jing-an CHEN Fang-xin LEI Ping 《Journal of Mountain Science》 SCIE CSCD 2018年第2期327-339,共13页
The source and sink landscape patterns refer to landscape types or units that can either promote positive evolvement of non-point source(NPS) pollution process, or can prevent/defer the ecological process, respectivel... The source and sink landscape patterns refer to landscape types or units that can either promote positive evolvement of non-point source(NPS) pollution process, or can prevent/defer the ecological process, respectively. Therefore, the role of a catchment landscape pattern in nutrient losses can be identified based on the spatial arrangement of source and sink landscapes. To reveal the relations between landscape spatial characteristics and NPS pollution in small catchment, a case study was carried out in a Wangjiagou small catchment of the Three Gorges Reservoir Region(TGRR), China. Google earth imagery for 2015 were processed and used to differentiate source and sink landscape types, and six subcatchments were selected as sample regions for monitoring nitrogen and phosphorus nutrients.Relative elevation, slope gradient and relative flow length was used to construct the Lorenz curves of different source and sink landscape types in the catchment, in order to assess the source and sink landscape spatial characteristics. By calculating the location-weighted landscape indices of each subcatchment and total catchment, the landscape spatial load characteristics affecting the NPS pollution was identified, with a further Pearson correlation analysis for location-weighted landscape indices and nitrogen-phosphorus monitoring indicators. The analysis of Lorenz curve has revealed that the obtained distribution trend of Lorenz curve and curve area quantified well the spatial characteristics of source and sink landscape pattern related to the relative elevation, slope gradient and relative flow length in small catchment. Results of Pearson correction analysis indicated that location-weighted landscape index(LWLI) combining of terrain and landscape type factor did better in reflecting the status of nitrogen and phosphorus loss than the indices related to relative elevation, slope gradient and relative flow length. 展开更多
关键词 污染过程 空间安排 特征和 水库区 风景 集水 水池 Google
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Sedimentary geochemistry of the Yangtze River: Sediment source-to-sink tracing implication 被引量:2
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作者 Shouye YANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期268-268,共1页
关键词 长江 地球化学 沉积物 水文化学
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Effect of Source-Sink Manipulation on Photosynthetic Characteristics of Flag Leaf and the Remobilization of Dry Mass and Nitrogen in Vegetative Organs of Wheat 被引量:7
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作者 ZHANG Ying-hua SUN Na-na +6 位作者 HONG Jia-pei ZHANG Qi WANG Chao XUE Qing-wu ZHOU Shun-li HUANG Qin WANG Zhi-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第8期1680-1690,共11页
The photosynthetic characteristics of flag leaf and the accumulation and remobilization of pre-anthesis dry mass(DM) and nitrogen(N) in vegetable organs in nine wheat cultivars under different source-sink manipula... The photosynthetic characteristics of flag leaf and the accumulation and remobilization of pre-anthesis dry mass(DM) and nitrogen(N) in vegetable organs in nine wheat cultivars under different source-sink manipulation treatments including defoliation(DF), spike shading(SS) and half spikelets removal(SR) were investigated. Results showed that the SS treatment increased the photosynthetic rate(Pn) of flag leaf in source limited cultivar, but had no significant effect on sink limited cultivar. The SR treatment decreased the Pn of flag leaf. Grain DM accumulation was limited by source in some cultivars, in other cultivars, it was limited by sink. Grain N accumulation was mainly limited by source supply. The contribution of pre-anthesis dry mass to grain yield from high to low was stem, leaf and chaff, while the contribution of pre-anthesis N to grain N from high to low was leaf, stem and chaff. Cultivars S7221 and TA9818 can increase the contribution of remobilization of DM and N to grain at the maximum ratio under reducing source treatments, which may be the major reason for these cultivars having lower decrease in grain yield and N content under reducing source treatments. 展开更多
关键词 genotypic variation remobilization of pre-anthesis dry mass and nitrogen source-sink treatment WHEAT
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Effects of Radiations and Heat Source/Sink on a Casson Fluid Flow over Nonlinear Stretching Sheet 被引量:1
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作者 Chenna Sumalatha Shankar Bandari 《World Journal of Mechanics》 2015年第12期257-265,共9页
The present study deals with the flow over a nonlinearly stretching sheet of Casson fluid with the effects of radiation and heat source/sink. The Casson fluid model is used to characterize the non-Newtonian fluid beha... The present study deals with the flow over a nonlinearly stretching sheet of Casson fluid with the effects of radiation and heat source/sink. The Casson fluid model is used to characterize the non-Newtonian fluid behaviour. With the help of justified similarity transformations the governing equations were reduced to couple nonlinear ordinary differential equations. The effective numerical technique Keller Box method is used to solve these equations. The variations in velocity, temperature profiles were presented with the various values of nonlinear stretching parameter n and Casson parameter β. The nature of Skinfriction and Local nusselt number has presented. Effects of radiation and heat source/sink on temperature profiles have been discussed. 展开更多
关键词 NONLINEAR STRETCHING Sheet Casson Fluid Keller BOX Method Radiation Heat source/sink
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