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Genetic analysis and fine mapping of a grain size QTL in the smallgrain sterile rice line Zhuo201S
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作者 Bin Lei Jiale Shao +5 位作者 Feng Zhang Jian Wang Yunhua Xiao Zhijun Cheng Wenbang Tang Jianmin Wan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2155-2163,共9页
The development and application of the small-grain rice sterile line Zhuo201S(Z201S)has demonstrated its potential for mechanized hybrid rice seed production,leading to significant cost reductions.However,the molecula... The development and application of the small-grain rice sterile line Zhuo201S(Z201S)has demonstrated its potential for mechanized hybrid rice seed production,leading to significant cost reductions.However,the molecular mechanism responsible for the small-grain size characteristic of Z201S remains unclear.In this study,we conducted a genetic analysis using near-isogenic lines constructed from Z210S,a small-grain rice sterile line,and R2115,a normal-grain variety.The results revealed that the small-grain trait in Z201S is governed by a single partially dominant gene which also enhances grain number.Through mapping,we localized the causal gene to the short arm of chromosome 2,within a 113 kb physical region delimited by the molecular markers S2-4-1 and LB63.Transgenic analysis and gene expression assays indicated LOC_Os02g14760 as the most likely candidate gene,suggesting that the small-grain size trait of Z201S is controlled by a novel locus that has not been previously identified. 展开更多
关键词 RICE grain size map-based cloning
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Quantitative analysis of laser-generated ultrasonic wave characteristics and their correlation with grain size in polycrystalline materials
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作者 徐兆文 白雪 +2 位作者 马健 万壮壮 王超群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期526-543,共18页
Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a la... Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a large irradiation spot simultaneously generated ultrasonic longitudinal and shear waves at the epicenter under the slight ablation regime.An optimized denoising technique based on wavelet thresholding and variational mode decomposition was applied to reduce noise in shear waves with a low signal-to-noise ratio.An approach for characterizing grain size was proposed using spectral central frequency ratio(SCFR)based on time-frequency analysis.The results demonstrate that the generation regime of ultrasonic waves is not solely determined by the laser power density;even at high power densities,a high energy with a large spot can generate an ultrasonic waveform dominated by the thermoelastic effect.This is ascribed to the intensification of the thermoelastic effect with the proportional increase in laser irradiation spot area for a given laser power density.Furthermore,both longitudinal and shear wave SCFRs are linearly related to grain size in polycrystalline materials;however,the shear wave SCFR is more sensitive to finer-grained materials.This study holds great significance for evaluating metal material properties using laser ultrasound. 展开更多
关键词 laser-ultrasonics polycrystalline materials ultrasonic time-frequency characteristics grain size
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Influence of material characteristics on the failure mode and process of landslide dam
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作者 HU Liang ZHONG Qiming +3 位作者 CHEN Liang YANG Meng ZHANG Lucheng WU Hao 《Journal of Mountain Science》 2025年第1期89-109,共21页
Landslide dams,as frequent natural hazards,pose significant risks to human lives,property,and ecological environments.The grading characteristics and density of dam materials play a crucial role in determining the sta... Landslide dams,as frequent natural hazards,pose significant risks to human lives,property,and ecological environments.The grading characteristics and density of dam materials play a crucial role in determining the stability of landslide dams and the potential for dam breaches.To explore the failure mechanisms and evolutionary processes of landslide dams with varying soil properties,this study conducted a series of flume experiments,considering different grain compositions and material densities.The results demonstrated that grading characteristics significantly influence landslide dam stability,affecting failure patterns,breach processes,and final breach morphologies.Fine-graded materials exhibited a sequence of surface erosion,head-cut erosion,and subsequent surface erosion during the breach process,while well-graded materials typically experienced head-cut erosion followed by surface erosion.In coarse-graded dams,the high permeability of coarse particles allowed the dam to remain stable,as inflows matched outflows.The dam breach model experiments also showed that increasing material density effectively delayed the breach and reduced peak breach flow discharge.Furthermore,higher fine particle content led to a reduction in the residual dam height and the base slope of the final breach profile,although the relationship between peak breach discharge and the content of fine and coarse particles was nonlinear.To better understand breach morphology evolution under different soil characteristics and hydraulic conditions,three key points were identified—erosion point,control point,and scouring point.This study,by examining the evolution of failure patterns,breach processes,and breach flow discharges under various grading and density conditions,offers valuable insights into the mechanisms behind landslide dam failures. 展开更多
关键词 Landslide dams OVERTOPPING Grain size distribution Breaching process Outflow discharge
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Utilizing sediment grain size characteristics to assess the effectiveness of clay–sand barriers in reducing aeolian erosion in Minqin desert area,China
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作者 SONG Dacheng ZHAO Wenzhi +5 位作者 LI Guangyu WEI Lemin WANG Lide YANG Jingyi WU Hao MA Quanlin 《Journal of Arid Land》 SCIE CSCD 2024年第5期668-684,共17页
The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 a.However,studies on evaluating the long-term effectiveness of clay–sand b... The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 a.However,studies on evaluating the long-term effectiveness of clay–sand barriers against aeolian erosion,particularly from the perspective of surface sediment grain size,are limited and thus insufficient to ascertain the protective impact of these barriers on regional aeolian activities.This study focused on the surface sediments(topsoil of 0–3 cm depth)of clay–sand barriers in Minqin desert area to explain their erosion resistance from the perspective of surface sediment grain size.In March 2023,six clay–sand barrier sampling plots with clay–sand barriers of different deployment durations(1,5,10,20,40,and 60 a)were selected as experimental plots,and one control sampling plot was set in an adjacent mobile sandy area without sand barriers.Surface sediment samples were collected from the topsoil of each sampling plot in the study area in April 2023 and sediment grain size characteristics were analyzed.Results indicated a predominance of fine and medium sands in the surface sediments of the study area.The deployment of clay–sand barriers cultivated a fine quality in grain size composition of the regional surface sediments,increasing the average contents of very fine sand,silt,and clay by 30.82%,417.38%,and 381.52%,respectively.This trend became markedly pronounced a decade after the deployment of clay–sand barriers.The effectiveness of clay–sand barriers in erosion resistance was manifested through reduced wind velocity,the interception of sand flow,and the promotion of fine surface sediment particles.Coarser particles such as medium,coarse,and very coarse sands predominantly accumulated on the external side of the barriers,while finer particles such as fine and very fine sands concentrated in the upwind(northwest)region of the barriers.By contrast,the contents of finest particles such as silt and clay were higher in the downwind(southeast)region of the sampling plots.For the study area,the deployment of clay–sand barriers remains one of the most cost-effective engineering solutions for aeolian erosion control,with sediment grain size parameters serving as quantitative indicators for the assessment of these barriers in combating desertification.The results of this study provide a theoretical foundation for the construction of windbreak and sand fixation systems and the optimization of artificial sand control projects in arid desert areas. 展开更多
关键词 clay-sand barriers sediment grain size grain size distribution aeolian erosion windbreak and sand fixation Minqin desert area
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Grain size and surface micro-texture characteristics and their paleoenvironmental significance of Holocene sediment in southern margin of the Gurbantunggut Desert,China
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作者 MA Yunqiang LI Zhizhong +2 位作者 TAN Dianjia ZOU Xiaojun TAO Tonglian 《Journal of Arid Land》 SCIE CSCD 2024年第5期632-653,共22页
The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant imp... The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant importance for understanding the interactive processes of wind and water forces,as well as the provenance of sediment.However,there are relatively few investigations on the characteristics of such sediment at present.In this study,we researched three aeolian-alluvial interactive stratigraphic profiles and different types of surface sediment on the desert-oasis transitional zone of southern margin of the Gurbantunggut Desert.Based on the optically stimulated luminescence(OSL)dating of aeolian sand and analyses of quartz sand grain size and surface micro-texture,we explored the aeolian-alluvial environmental change at southern margin of the desert in Holocene,as well as the provenance of sediment.The results indicated that the grain size characteristics of different types of sediment in the stratigraphic profiles were similar to those of modern dune sand,interdune sand,muddy desert surface soil,and riverbed sand.Their frequency curves were unimodal or bimodal,and cumulative probability curves were two-segment or three-segment,mainly composed of suspension load and saltation load.The quartz sand in the sediment at southern margin of the desert had undergone alternating transformation of various exogenic forces,with short transportation distance and time,and sedimentary environment was relatively humid.In Holocene,southern margin of the desert primarily featured braided river deposits,and during intermittent period of river activity,there were also aeolian deposits such as sand sheet deposits,stabilized dune deposits,and mobile dune deposits.The provenance for Holocene alluvial deposits at southern margin of the desert remains relatively constant,with the debris of the Tianshan Mountains being the primary provenance.Aeolian sand is mainly near-source recharge,which is formed by in situ deposition of fluvial or lacustrine materials in southern margin of the desert transported by wind erosion,and its provenance was still the weathered debris of the Tianshan Mountains.In addition,the sand in interior of the desert may be transported by northwest wind in desert-scale,thus affecting the development of dunes in southern margin of the desert.The results of this study provide a reference for understanding the composition and provenance changes of desert sand in the context of global climate change. 展开更多
关键词 aeolian-alluvial deposition grain size surface micro-texture sedimentary environment HOLOCENE
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Effect of Skeleton Grain Size on the Saturation of Gas Hydrate in Natural Sediments
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作者 XU Zhenqiang LI Yang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期676-682,共7页
Natural gas hydrate is prospected as a new and promising,highly clean energy resource that mainly occurs in perma-frost or at continental margins.Its formation is subject to many soil conditions,such as grain size,mat... Natural gas hydrate is prospected as a new and promising,highly clean energy resource that mainly occurs in perma-frost or at continental margins.Its formation is subject to many soil conditions,such as grain size,matrix materials,pore morphology,and permeability.In this study,we propose that grain size is the most decisive parameter that affects the saturation of gas hydrate in sediments based on data from Ocean Drilling Program Leg 164 and Mallik 5L-38,which represent marine sediments and terrestrial sediments,respectively.Our study reveals that high gas hydrate saturation generally occurs in coarse-grained sand,regardless of whether sediment formation is homogeneous or inhomogeneous,and the sorting of sediments may affect the hydrate saturation to a certain degree.Using grain size and sorting of sediments may be the most intuitive proxy method for a rough estimation of hydrate saturation.Further study is necessary to fully understand the relationship between hydrate morphology and sediment grain size,even though massive hydrates are typically found in fine clayey-rich sediments. 展开更多
关键词 grain size SATURATION gas hydrates ODP Leg 164 Mallik 5L-38
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Paleoenvironmental changes recorded by grain size of loess/paleosol sequence from the Chifeng City,Northeastern China since the Last Glacial
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作者 LI Juan BRYE Kristofor R +2 位作者 ZHANG Mengge JIANG Zhuodong WANG Qiubing 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3068-3082,共15页
The accumulation processes of loess in northeastern(NE)China record the varying characteristics of the East Asian Monsoons(EAM)and the evolution of the local environment.In this study,grain size end-member analysis of... The accumulation processes of loess in northeastern(NE)China record the varying characteristics of the East Asian Monsoons(EAM)and the evolution of the local environment.In this study,grain size end-member analysis of the Dajiugang(DJG)section deposited since the Last Glacial in Chifeng City,NE China was used to reveal the dynamic depositional characteristics of loess and environmental evolution of NE China.Results showed that the Chifeng loess comprises three grain size end-members(EM),EM1(7.38μm),EM2(49.4μm)and EM3(90.00μm),indicating the three transport dynamics of dust delivered to the region.The EM1 represents atmospheric dust as the background.The EM2,mainly derived from relatively distant-sources deposition,and EM3,material transported over a short distance,correspond to the intensity of southwesterly winds and the East Asian Winter Monsoon(EAWM),respectively.Results of climate reconstruction,combined with other records,showed that the climate was generally cold and dry with a strong EAWM and a weak East Asian summer monsoon(EASM)during the stadial-period[Marine Isotope Stage(MIS)4 and MIS 2 stage].The climate was predominantly warm and humid,with weak EAWM and surface winds and strong EASM in interstadial-period(MIS 3 and MIS 1 stage).Comparisons between indicators,e.g.,EM3,the LR04 benthicδ18O stack and summer insolation at 65°N suggest that the strong EAWM is induced by increasing the Northern Hemisphere ice volume and reduced summer solar radiation. 展开更多
关键词 Loess deposit Grain size end-member Northeastern China Environmental change the Last Glacial
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The dual role of casein kinase 1,DTG1,in regulating tillering and grain size in rice
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作者 Jijin Li Dan Zhou +19 位作者 Deke Li Gen Wang Rui Qin Chengqin Gong Kang Chen Yunqing Tong Lingfeng Li Keke Liu Jiangkun Ye Binjiu Luo Chenglong Jiang Haipeng Wang Jinghua Jin Qiming Deng Shiquan Wang Jun Zhu Ting Zou Shuangcheng Li Ping Li Yueyang Liang 《The Crop Journal》 SCIE CSCD 2024年第6期1569-1582,共14页
Tiller number and grain size are important agronomic traits that determine grain yield in rice.Here,we demonstrate that DEFECTIVE TILLER GROWTH 1(DTG1),a member of the casein kinase 1 protein family,exerts a co-regula... Tiller number and grain size are important agronomic traits that determine grain yield in rice.Here,we demonstrate that DEFECTIVE TILLER GROWTH 1(DTG1),a member of the casein kinase 1 protein family,exerts a co-regulatory effect on tiller number and grain size.We identified a single amino acid substitution in DTG1(I357K)that caused a decrease in tiller number and an increase in grain size in NIL-dtg1.Genetic analyses revealed that DTG1 plays a pivotal role in regulation of tillering and grain size.The DTG1^(I357K) allelic variant exhibited robust functionality in suppressing tillering.We show that DTG1 is preferentially expressed in tiller buds and young panicles,and negatively regulates grain size by restricting cell proliferation in spikelet hulls.We further confirm that DTG1 functioned in grain size regulation by directly interacting with Grain Width 2(GW2),a critical grain size regulator in rice.The CRISPR/Cas9-mediated elimination of DTG1 significantly enhanced tiller number and grain size,thereby increasing rice grain yield under field conditions,thus highlighting potential value of DTG1 in rice breeding. 展开更多
关键词 Oryza sativa Tiller number Grain size Casein kinase 1 DTG1
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Particle size characterization and sources of sediments in the Uzhumqin sand dunes
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作者 ZHANG Hao LIU Yang +3 位作者 DANG Xiaohong MENG Zhongju LI Shuangli GAO Yong 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2631-2645,共15页
Sediment constitutes the fundamental basis for forming and evolving aeolian geomorphology.The characteristics of sediment particle size offer insights into the development and evolution of sandy terrain,making their s... Sediment constitutes the fundamental basis for forming and evolving aeolian geomorphology.The characteristics of sediment particle size offer insights into the development and evolution of sandy terrain,making their study critical to understanding aeolian geomorphology and sand control.In this study,we combined high-density collection of surface sediments in the Uzhumqin sand dunes and GIS spatial analysis to analyze the particle size parameters and changes in the spatial distribution of surface sediments in this region.In addition,we used an end-member analysis to identify the potential sources of the sediments.The results showed that surface sediments in the Uzhumqin sand dunes had distinct spatial distributions.Medium and coarse grain sands dominated the sediments in the dunes,and the mean grain size and the sorting coefficient generally increased along the prevailing wind direction,with high values in individual areas related to factors such as material sources and vegetation cover.Skewness was strongly influenced by factors such as landform change and human activity,and spatial variability became more complex.Kurtosis and the soil fractal dimension showed generally decreasing trends along the prevailing wind direction.With dune fixation,the contents of clay and powder particles in the soil increased;the mean particle size,the sorting coefficient,and the fractal dimension of the soil gradually increased,and the skewness and kurtosis gradually decreased.The end-member analysis results indicated the existence of five end-members(EM)in the dune sediments.EM 1 was a mixed component of wind-deposited fine sands and nearby fluvial sediments.EM 2 was the main component of sediments in the study area and was the result of sorting lake sediments by wind action and by the local topography.EM 3 may be a product of river flood deposition.EM 4 and EM 5 had coarser grain sizes.EM 4 was a lake-phase sediment product influenced by topographic and vegetation cover factors,and EM 5 was primarily a river and lake sediment product modified by weathering.The sediment particle size results from the study area indicate that the sediment in the sandy region is generally coarse due to multiple factors,including topography,climate,hydrology,and human activity.Sandy material in the study area originated from nearby,with very little sand being transported from long distances. 展开更多
关键词 SEDIMENT Particle size Spatial differences End-member analysis Uzhumqin sand dunes
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Changes of grain size from peat profile in eastern mountainous area over past 2000 years,Jilin Province,Northeast China
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作者 ZHANG Xinrong WANG Jiayu +1 位作者 PING Shuaifei LI Yaran 《Global Geology》 2024年第3期132-144,共13页
Plenty of high-resolution paleoclimate investigations of the last thousand years were carried out to potentially predict future climate changes.Mountainous ombrotrophic peatland is one of the best recorders for high-r... Plenty of high-resolution paleoclimate investigations of the last thousand years were carried out to potentially predict future climate changes.Mountainous ombrotrophic peatland is one of the best recorders for high-resolution paleoclimate studies in the forest area.Grain size analysis was carried out on ombrotrophic peat profile in the eastern mountainous region of Jilin Province,Northeast China.The peat profile lasts the past 2000 a by four radiocarbon(AMS14C)ages.The results showed that the inorganic minerals in the peat profile are mainly silt,with some contribution from clay and a minor amount of sand,which are mainly due to wind dust and suspended transportation.Two paleoclimate stages are found in this peat profile by phytolith analysis,peat cellulose isotope research and historical documents:ca.45–1550 AD,relatively cold period;ca.1550 AD–present,relatively warm period.This finding is important for the initial study of paleoclimatic changes over the last 2000 a in the mountainous area of eastern mountainous area,Jilin Province,Northeast China. 展开更多
关键词 peat sediments grain size analysis PALEOCLIMATE
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The Role of the Size Effect on the Drying of Refractory Castables—How Its Under-standing Could Narrow the Gap between Laboratory Studies and Industrial Reality
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作者 M.H.MOREIRA H.PENG +1 位作者 S.Dal PONT V.C.PANDOLFELLI 《China's Refractories》 CAS 2024年第2期35-40,共6页
Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some... Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some circumstances resistance to erosion from abrasive particles.Given the large processing output of the heavy industries such as the cement and steel ones which both require high temperature processes,the refractories structures span various meters and weight of several tons.As the water removal stage of hydraulic bonded castables in industrial sites takes hours(10-60 h)due to the risk of explosive spalling,efforts to mitigate it are commonly studied.This has provided theoretical understanding of the general aspects of drying and important tools,such as the thermogravimetry analysis(TGA),for the design of refractory compositions with higher explosive spalling resistance.However,the optimization of this process is still far from the industrial reality especially because the actual linings that require the drying are orders of magnitude larger than the samples considered in the laboratory tests.Therefore,this study proposed the analysis of the sample volume effect on the water removal dynamics through TGA of high alumina castables with calcium aluminate cement.Conventionalφ5 cm×5 cm cylindrical samples were assessed in a laboratory scale equipment whereas macro TGA were carried out considering 20 cm×20 cm×20 cm and 30 cm×30 cm×30 cm cubic samples.Additionally,the effect of polymeric fibers was also considered.It was found out that the different thermal gradients within the macro TGA samples resulted in an inflection on the sample’s heating rate and that the mass loss was affected by the volume considered,especially for the composition without additives.These findings highlight the requirement of carefully taking into consideration the different dimensional sizes and thermal gradients in the samples when analyzing and interpreting the laboratory studies,and especially when trying to extrapolate such results to the industrial reality. 展开更多
关键词 DRYING refractory castables size effect thermogravimetry analysis
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The application of geostatistics in grain size trend analysis: A case study of eastern Beibu Gulf 被引量:15
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作者 MA Fei WANG Yaping +3 位作者 LI Yan YE Changjiang XU Zhiwei ZHANG Fan 《Journal of Geographical Sciences》 SCIE CSCD 2010年第1期77-90,共14页
There are 71 surface sediment samples collected from the eastern Beibu Gulf. The moment parameters (i.e. mean size, sorting and skewness) were obtained after applying grain size analysis. The geostatistical analysis... There are 71 surface sediment samples collected from the eastern Beibu Gulf. The moment parameters (i.e. mean size, sorting and skewness) were obtained after applying grain size analysis. The geostatistical analysis was then applied to study the spatial autocorrelation for these parameters; while range, a parameter in the semivariogram that meters the scale of spatial autocorrelation, was estimated. The results indicated that the range for sorting coefficient was physically meaningful. The trend vectors calculated from grain size trend analysis model were consistent with the annual ocean circulation patterns and sediment transport rates according to previous studies. Therefore the range derived from the semivariogram of mean size can be used as the characteristic distance in the grain size trend analysis, which may remove the bias caused by the traditional way of basing on experiences or testing methods to get the characteristic distance. Hence the results from geostatistical analysis can also offer useful information for the determination of sediment sampling density in the future field work. 展开更多
关键词 geostatistical method SEMIVARIOGRAM grain size trend analysis sediment transport Beibu Gulf
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The reverse sediment transport trend between abandoned Huanghe River(Yellow River) Delta and radial sand ridges along Jiangsu coastline of China——an evidence from grain size analysis 被引量:5
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作者 LIU Tao SHI Xuefa +1 位作者 LI Chaoxina YANG Gang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第6期83-91,共9页
To reveal the sediment transporting mechanism between the abandoned Huanghe River (Yellow River) Delta and radial sand ridges, “End Member” Model and grain size trend analysis have been employed to separate the “... To reveal the sediment transporting mechanism between the abandoned Huanghe River (Yellow River) Delta and radial sand ridges, “End Member” Model and grain size trend analysis have been employed to separate the “dynamic populations” in the surficial sediment particle spectra and to determine the possible sediment transporting pathway. The results reveal four “dynamic subpopulations”(EM1 to EM4) and two reverse sediment transporting directions: a northward transport tend from the radial sand ridges to mud patch, and a southward transport trend in deep water area outside the mud patch. Combined with the published hydrodynamic information, the transporting mechanism of dynamic populations has been discussed, and the main conclusion is that the transporting of finer subpopulations EM1 and EM2 is controlled by the “anticlockwise residual current circulation” forming during tidal cycle, which favor a northward transporting trend and the forming of mud patch on the north of radial sand ridges, while the transporting of coarser EM3 is mainly controlled by wind driven drift in winter, which favors a southward transporting direction. 展开更多
关键词 radial sand ridges sediment transport grain size trend analysis end member model
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Characteristics of grain size distribution and the shear strength analysis of Chenjiaba long runout coseismic landslide 被引量:2
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作者 GETAHUN Ephrem QI Sheng-wen +2 位作者 GUO Song-feng ZOU Yu LIANG Ning 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2110-2125,共16页
Study on the grain size distribution characteristics and the frictional strength behavior of the slide deposits are helpful to disclose the landslide runout process and understand the mechanism of a long runout landsl... Study on the grain size distribution characteristics and the frictional strength behavior of the slide deposits are helpful to disclose the landslide runout process and understand the mechanism of a long runout landslide. We performed grain size distribution analysis on samples collected from Chenjiaba landslide induced by Wenchuan earthquake. The grain size distribution of samples from the landslide sections quantitatively depicts a gradual coarsening upward grading from shear zone to the top section. Then a multistage-multiphase ring shearing approach was used to determine a comparative shear strength behavior of samples from each landslide section. In this method, a sample was sheared continuously for large displacement and fast rate on different normal stress conditions. The multiphase shear mode with a maximum of 105 mm/min rate has allowed observing the qualitative change and patterns of the frictional resistance behaviors of soils under different normal stresses. The results of coefficient of friction values under multiphase shear mode have shown substantial post peak shear weakening behaviors after large shear displacement that can be narrated with long runout processes. The shear strength test results indicate that the shear zone samples have developed higher friction angle values compared to overlying section samples, on the last phase of shear process, which may be very important to understand the braking mechanism of a long runout landslide. 展开更多
关键词 GRAIN size distribution Long RUNOUT LANDSLIDE Multistage-Multiphase Ring Shear
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Impacts of sample size for stomach content analysis on the estimation of ecosystem indices 被引量:1
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作者 Dongyan Han Chongliang Zhang +3 位作者 Ying Xue Binduo Xu Yiping Ren Yong Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第8期53-61,共9页
This study used Ecopath model of the Jiaozhou Bay as an example to evaluate the effect of stomach sample size of three fish species on the projection of this model. The derived ecosystem indices were classified into t... This study used Ecopath model of the Jiaozhou Bay as an example to evaluate the effect of stomach sample size of three fish species on the projection of this model. The derived ecosystem indices were classified into three categories:(1) direct indices, like the trophic level of species, influenced by stomach sample size directly;(2)indirect indices, like ecology efficiency(EE) of invertebrates, influenced by the multiple prey-predator relationships;and(3) systemic indices, like total system throughout(TST), describing the status of the whole ecosystem. The influences of different stomach sample sizes on these indices were evaluated. The results suggest that systemic indices of the ecosystem model were robust to stomach sample sizes, whereas specific indices related to species were indicated to be with low accuracy and precision when stomach samples were insufficient.The indices became more uncertain when the stomach sample sizes varied for more species. This study enhances the understanding of how the quality of diet composition data influences ecosystem modeling outputs. The results can also guide the design of stomach content analysis for developing ecosystem models. 展开更多
关键词 computer simulation Ecopath with Ecosim ecosystem index optimization sample size stomach contents analysis
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Quality of Service Analysis of Ethernet Network Based on Packet Size 被引量:1
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作者 Nazrul Islam Chayan Chandra Bawn +2 位作者 Jahid Hasan Asma Islam Swapna Md. Syfur Rahman 《Journal of Computer and Communications》 2016年第4期63-72,共10页
Ethernet network, standardized by IEEE 802.3, is vastly installed in Local Area Network (LAN) for cheaper cost and reliability. With the emergence of cost effective and enhanced user experience needs, the Quality of S... Ethernet network, standardized by IEEE 802.3, is vastly installed in Local Area Network (LAN) for cheaper cost and reliability. With the emergence of cost effective and enhanced user experience needs, the Quality of Service (QoS) of the underlying Ethernet network has become a major issue. A network must provide predictable, reliable and guaranteed services. The required QoS on the network is achieved through managing the end-to-end delay, throughput, jitter, transmission rate and many other network performance parameters. The paper investigates QoS parameters based on packet size to analyze the network performance. Segmentation in packet size larger than 1500 bytes, Maximum Transmission Unit (MTU) of Ethernet, is used to divide the large data into small packets. A simulation process under Riverbed modeler 17.5 initiates several scenarios of the Ethernet network to depict the QoS metrics in the Ethernet topology. For analyzing the result from the simulation process, varying sized packets are considered. Hence, the network performance results in distinct throughput, end-to-end delay, packet loss ratio, bit error rate etc. for varying packet sizes. 展开更多
关键词 QOS Ethernet Network Performance analysis Packet size SEGMENTATION
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Application of Grain Size Analysis to Study Sedimentary Environment of Sand Dune in the Vicinity of Tumen River 被引量:1
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作者 Feng Ma Li Liu Lin Cao 《Global Geology》 2003年第1期65-68,共4页
The average size of the sand of dune in the vicinity of Tumen River is 0.12~0.30 mm, its standard deviation is 0.45~0.99 φ and the frequency cumulative distribution curve is divided into the single peak and the dou... The average size of the sand of dune in the vicinity of Tumen River is 0.12~0.30 mm, its standard deviation is 0.45~0.99 φ and the frequency cumulative distribution curve is divided into the single peak and the double peak. The Ski of the single peak is negative and the double peak is positive. There are two different areas in the plot of the Ski versus σi* It is shown that the sedimentary environment of the dunes is neritic deposit by the expressions of the grain-size parameters. All of the characters show that the sand dunes in Estuary of Tumen River may be the dunes of sea facies which were changed again by weathering and fluvialaction. 展开更多
关键词 Tumen River grain size analysis sedimentary environment
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Analysis of the Break Size Influence on the Damage Accident of Single Heat Transfer Tube of Ship Nuclear Power Steam Generator
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作者 Meng Cai Wei Wang +1 位作者 Junzhong Sun Renxi Jin 《World Journal of Engineering and Technology》 2017年第4期21-32,共12页
In view of the problem that the breakage size is not enough to analyze the damage of the heat transfer tube of the ship nuclear power steam generator under the condition that the breakage loop cannot be isolated, this... In view of the problem that the breakage size is not enough to analyze the damage of the heat transfer tube of the ship nuclear power steam generator under the condition that the breakage loop cannot be isolated, this paper analyzes the damage safety analysis model based on the MELCOR program, Damage of heat transfer tubes at different break sizes (2 mm and 6 mm) to reactor power, primary loop pressure, regulator water level, core water level, vapor pressure, break flow, fuel element cladding breakage, etc. The influence of the breakage size on the damage effect of the heat transfer tube has improved the analysis and handling capacity of the damage of the heat transfer tube, and improved the reactor accident handling capacity under the condition of the damage of the heat transfer tube. 展开更多
关键词 Steam Generator DAMAGE Safety analysis BREAK size
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Analysis of the Effect of Subgroup Size on the X-Bar Control Chart Using Forensic Science Laboratory Sample Influx Data
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作者 Samwel Victor Manyele 《Engineering(科研)》 2017年第5期434-456,共23页
This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points... This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points (OCP), upper control limit UCLx, and zonal demarcations. Multi-rules were used to identify the number of out-of-control-points, Nocp as violations using five control chart rules applied separately. A sensitivity analysis on the Nocp was applied for subgroup size, k, and number of sigma above the mean value to determine the upper control limit, UCLx. A computer code was implemented using a FORTRAN code to create x-bar control-charts and capture OCP and other control-chart characteristics with increasing k from 2 to 25. For each value of k, a complete series of average values, Q(p), of specific length, Nsg, was created from which statistical analysis was conducted and compared to the original SIF data, S(t). The variation of number of out-of-control points or violations, Nocp, for different control-charts rules with increasing k was determined to follow a decaying exponential function, Nocp = Ae–α, for which, the goodness of fit was established, and the R2 value approached unity for Rule #4 and #5 only. The goodness of fit was established to be the new criteria for rational subgroup-size range, for Rules #5 and #4 only, which involve a count of 6 consecutive points decreasing and 8 consecutive points above the selected control limit (σ/3 above the grand mean), respectively. Using this criterion, the rational subgroup range was established to be 4 ≤ k ≤ 20 for the two x-bar control chart rules. 展开更多
关键词 Forensic Science LABORATORY SAMPLE Influx Statistical analysis X-bar Control CHART Sub-Group size Control CHART Rules Multi-Rules for X-Bar CHART Out-of-Control Points
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Grain Size Analysis and Wave Modeling on the Coastal Fringe of Larache (Ras R'mel Beach), North West of Morocco
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作者 Nadia El Mekadem Brahim EI Moutchoul +1 位作者 Ana M. Bemabeu Khalil El Hajjaji 《Journal of Shipping and Ocean Engineering》 2012年第4期244-248,共5页
The studied area is located in the northwestern Morocco. It occupies a 2.5 km long of coastline on the Atlantic shore. It is oriented NNE-SSW, clearly exposed to the dominant swells coming from west to northwest. The ... The studied area is located in the northwestern Morocco. It occupies a 2.5 km long of coastline on the Atlantic shore. It is oriented NNE-SSW, clearly exposed to the dominant swells coming from west to northwest. The aim of this study is to determine the capacity of the waves that hit the shore to transport the sediments. To achieve our goal we chose a methodology that combines field sampling and laboratory analysis with digital modeling. In the first phase we sampled sediments from the study area along and across the beach line, dry sieving was used to determine the grain size distribution and the statistics derived from the sand samples were used to determine the critical shield stress (z'cr, b) also to investigate the spatial variability and influence of transport on grain size characteristics. As for the second phase, we intended to create a wave climate modeling based on nautical chart, using ArcGIS then Matlab that allowed us to obtain the Swan model for the area. The correlation between those results showed the degree of contribution of wave in the distribution of sediments along the shore. 展开更多
关键词 Grain size sedimentary distribution wave modeling Atlantic coast.
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