|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Magnetostratigraphy of borehole EY02-2 in the southern Yellow Sea and its paleoenvironmental significance显示文摘Detailed rock magnetic and paleomag- netic studies have been undertaken on borehole EY02-2 (70m in length) in the southern Yellow Sea (SYS). The main Curie point revealed by magnetic susceptibility-temperature (k-T) curve is 580―600℃ indicating magnetite dominance. The hysteresis loop parameters show large variation of magnetic minera size in different sedimentary contexts: it is larger in subtidal sediment than in terrigenous sediment and even larger than in shallow sea sediment. This trend is correlative with distance to sediment source and dynamic strength. Magnetostratigraphic results show that the M/B polarity boundary (MBPB) is at 63.29m and there are at least 7 polarity transitions (Nr1-7) in Brunhes chron that can be tentatively correlated with 6 named polarity reversals. Three positive polarity reversals occur in late Matuyama chron and the early two may be the record of Kamikatsura happening in 886±3 kaB.P. Magnetic susceptibility (MS) and sediment grain size behave so differently in some sedimentary facies that certain big environmenta changes can be clearly revealed. Generally, the MS and grain size of subtidal and terrigenous sediments are larger than shallow sea sediments and MS value around 10×10?5SI and mean grain size of 7Φ seems to be indicators of shallow sea sediments of deep water depth. However, the frequently used excellen climatic proxies such as MS and grain size in loess and deep sea sediments fail to record such climatic cycles revealed by oxygen isotope in continental seaThe various sediment sources, sedimentation dy- namic and their complex changes between glacial and interglacial periods should be the cause of fail- ure. | GE Shulan SHI Xuefa ZHU Rixiang LIU Yanguang YIN Ping LIU Lejun | 2006 | Chinese Science Bulletin2006，51，7： | 6 |
| 2 | Runout prediction and dynamic characteristic analysis of a potential submarine landslide in Liwan 3-1 gas field显示文摘A large number of submarine landslides with different scales have been identified in the canyon area of the submarine pipeline route of Liwan 3-1 gas field. There is still much chance that submarine slope failures would happen, and the following mass movement would present great risk to the submarine pipeline. In view of this, a numerical prediction method based on Eulerian-Eulerian two-phase flow model is introduced to simulate the mass movement of potential submarine landslides. The sliding soil and ambient water are respectively simulated by Herschel-Bulkley rheology model and Newtonian fluid model. The turbulence is simulated using the k-e model. Compared with both the experiment data and Bing result, the two-phase flow model shows a good accuracy, and its result is more close to the actual situation; the dynamic coupling between soil and ambient water can be effectively simulated and the phenomena of hydroplaning and head detachment can be obtained.Finally, the soil movement of a potential submarine landslide is simulated as an example, according to the seismic profile in the canyon area. The result shows that the hydroplaning occurs during the movement process. The runout distance calculated by the two-phase flow model is 877 m, which is 27.1% larger than the Bing result.However, the peak front velocity of soil is relative small, with a maximum value of 8.32 m/s. The Bing program with a simple and rapid process can be used for a preliminary evaluation, while the two-phase flow model is more appropriate for an accurate assessment. | XIU Zongxiang LIU Lejun XIE Qiuhong LI Jiagang HU Guanghai YANG Jianghui | 2015 | Acta Oceanologica Sinica2015，34，7： | 6 |
| 3 | Prediction for Potential Landslide Zones Using Seismic Amplitude in Liwan Gas Field, Northern South China Sea显示文摘The Liwan(Lw) gas field located in the northern slope of the South China Sea(SCS) is extremely complex for its seafloor topograghy, which is a huge challenge for the safety of subsea facilities. It is economically impractical to obtain parameters for risk assessment of slope stability through a large amount of sampling over the whole field. The linkage between soil shear strength and seabed peak amplitude derived from 2D/3D seismic data is helpful for understanding the regional slope-instability risk. In this paper, the relationships among seabed peak, acoustic impedance and shear strength of shallow soil in the study area were discussed based on statistical analysis results. We obtained a similar relationship to that obtained in other deep-water areas. There is a positive correlation between seabed peak amplitude and acoustic impedance and an exponential relationship between acoustic impedance and shear strength of sediment. The acoustic impedance is the key factor linking the seismic amplitude and shear strength. Infinite slope stability analysis results indicate the areas have a high potential of shallow landslide on slopes exceeding 15? when the thickness of loose sediments exceeds 8 m in the Lw gas field. Our prediction shows that they are mainly located in the heads and walls of submarine canyons. | LI Xishuang LIU Baohua LIU Lejun ZHENG Jiewen ZHOU Songwang ZHOU Qingjie | 2017 | Journal of Ocean University of China2017，16，6： | 4 |
| 4 | Mass movements in small canyons in the northeast of Baiyun deepwater area, north of the South China Sea显示文摘The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass movements in small submarine canyons in the northeast of Baiyun deepwater area, north of the South China Sea(SCS), and their strong effects on the evolution of the canyons based on geophysical data. Submarine canyons in the study area arrange closely below the shelf break zone which was at the depth of –500 m. Within submarine canyons, seabed surface was covered with amounts of failure scars resulted from past small-sized landslides. A complex process of mass transportation in the canyons is indicated by three directions of mass movements.Recent mass movement deposits in the canyons exhibit translucent reflections or parallel reflections which represent the brittle deformation and the plastic deformation, respectively. The area of most landslides in the canyons is less than 3 km2. The trigger mechanisms for mass movements in the study area are gravitational overloading, slope angle and weak properties of soil. Geophysical data indicate that the genesis of submarine canyons is the erosion of mass movements and consequent turbidity currents. The significant effects of mass movements on canyon are incision and sediment transportation at the erosion phases and fillings supply at the fill phases. This research will be helpful for the geological risk assessments and understanding the sediment transportation in the northern margin of the SCS. | LI Xishuang LIU Lejun LI Jiagang GAO Shan ZHOU Qingjie SU Tianyun | 2015 | Acta Oceanologica Sinica2015，34，8： | 4 |
| 5 | Preparations,Characterizations and Applications of Chitosan-based Nanoparticles显示文摘Chitosan is a natural polysaccharide prepared by the N-deacetylation of chitin. In this paper we have reviewed the methods of preparation of chitosan-based nanoparticles and their pharmaceutical applications. There are five methods of their prepa-rations:emulsion cross-linking,emulsion-droplet coalescence,ionic gelation,reverse micellar method and chemically modified chi-tosan method. Chitosan nanoparticles are used as carriers for low molecular weight drug,vaccines and DNA. Releasing characteris-tics,biodistribution and applications are also summarized. | LIU Chenguang TAN Yulong LIU Chengsheng CHEN Xiguang YU Lejun | 2007 | Journal of Ocean University of China2007，6，3： | 3 |
| 6 | Satellite Thermal Infrared Earthquake Precursor to the Wenchuan M_s 8.0 Earthquake in Sichuan,China,and its Analysis on Geo-dynamics显示文摘Based on an interpretation and study of the satellite remote-sensing images of FY-2C thermal infrared 1st wave band(10.3-11.3μm) designed in China,the authors found that there existed obvious and isolated satellite thermal infrared anomalies before the 5.12 Wenchuan M_s 8.0 Earthquake.These anomalies had the following characteristics:(1) The precursor appeared rather early:on March 18, 2008,i.e.,55 days before the earthquake,thermal infrared anomalies began to occur;(2) The anomalies experienced quite many and complex evolutionary stages:the satellite thermal infrared anomalies might be divided into five stages,whose manifestations were somewhat different from each other.The existence of so many anomaly stages was probably observed for the first time in numerous cases of satellite thermal infrared research on earthquakes;(3) Each stage lasted quite a long time,with the longest one spanning 13 days;(4) An evident geothermal anomaly gradient was distributed along the Longmen seismic fracture zone,and such a phenomenon might also be discovered for the first time in satellite thermal infrared earthquake research.This discovery is therefore of great guiding and instructive significance in the study of the earthquake occurrence itself and the trend of the postearthquake phenomena. | WEI Lejun GUO Jianfeng LIU Jianhua LU Zhenquan LI Haibing CAI Hui | 2009 | Acta Geologica Sinica(English Edition)2009，83，4： | 2 |
| 7 | Submarine Landslide Identified in DLW3102 Core of the Northern Continental Slope, South China Sea显示文摘In this paper, we take DLW3101 core obtained at the top of the canyon(no landslide area) and DLW3102 core obtained at the bottom of the canyon(landslide area) on the northern continental slope of the South China Sea as research objects. The chronostratigraphic framework of the DLW3101 core and elemental strata of the DLW3101 core and the DLW3102 core since MIS5 are established by analyzing oxygen isotope, calcium carbonate content, and X-Ray Fluorescence(XRF) scanning elements. On the basis of the information obtained by analyzing the sedimentary structure and chemical elements in the landslide deposition, we found that the DLW3102 core shows four layers of submarine landslides, and each landslide layer is characterized by high Si, K, Ti, and Fe contents, thereby indicating terrigenous clastic sources. L1(2.15–2.44 m) occurred in MIS2, which is a slump sedimentary layer with a small sliding distance and scale. L2(15.48–16.00 m) occurred in MIS5 and is a debris flow-deposited layer with a scale and sliding distance that are greater than those of L1. L3(19.00–20.90 m) occurred in MIS5; its upper part(19.00–20.00 m) is a debris flow-deposited layer, and its lower part(20.00–20.90 m) is a sliding deposition layer. The landslide scale of L3 is large. L4(22.93–24.27 m) occurred in MIS5; its upper part(22.93–23.50 m) is a turbid sedimentary layer, and its lower part(23.50–24.27m) is a slump sedimentary layer. The landslide scale of L4 is large. | XU Yuanqin LIU Lejun ZHOU Hang HUANG Baoqi LI Ping MA Xiudong DONG Feiyin | 2018 | Journal of Ocean University of China2018，17，1： | 2 |
| 8 | Mangrove forest degradation indicated by mangrove-derived organic matter in the Qinzhou Bay,Guangxi,China,and its response to the Asian monsoon during the Holocene climatic optimum显示文摘The response of mangrove ecosystems to the Asian monsoon in the future global warming can be understood by reconstructing the development of mangrove forests during the Holocene climatic optimum(HCO), using proxies preserved in coastal sediments. The total organic matter in sediments of a segmented core, with calibrated age ranges between 5.6 and 7.7 cal. ka BP and corresponding to the HCO, from the Qinzhou Bay in Guangxi, China, is quantitatively partitioned into three end-members according to their sources: mangrove-derived, terrigenous,and marine phytoplanktonic, using a three-end-member model depicted by organic carbon isotope(δ13Corg) and the molar ratio of total organic carbon to total nitrogen(C/N). The percentage of mangrove-derived organic matter(MOM) contribution is used as a proxy for mangrove development. Three visible drops in MOM contribution occurred at ca. 7.3, ca. 6.9, and ca. 6.2 cal. ka BP, respectively, are recognized against a relatively stable and higher MOM contribution level, indicating that three distinct mangrove forest degradations occurred in the Qinzhou Bay during the HCO. The three mangrove forest degradations approximately correspond to the time of the strengthened/weakened Asian winter/summer monsoon. This indicates that even during a period favorable for the mangrove development, such as the HCO, climatic extremes, such as cold and dry events driven by the strengthened/weakened Asian winter/summer monsoon, can trigger the degradation of mangrove forests. | MENG Xianwei XIA Peng LI Zhen LIU Lejun | 2016 | Acta Oceanologica Sinica2016，35，2： | 1 |
| 9 | Magnetostratigraphy of coastal loess of Dalian,China and its paleoclimatic significance显示文摘MagnetostratigraphyofcoastalloessofDalian,ChinaanditspaleoclimaticsignificanceLiPeiying;LiuBaozhu;LiuLejunandZhouMoqingAbstra... | Li Peiying Liu Baozhu Liu Lejun and Zhou Moqing | 1996 | Acta Oceanologica Sinica1996，15，4： | 1 |
| 10 | Preparation of ultrafine rhenium powders by CVD hydrogen reduction of volatile rhenium oxides显示文摘 | Bai Meng Liu Zhihong Zhou Lejun | 2013 | Transactions of the Nonferrous Metals Society of China2013，23，： | 1 |
| 11 | The difference analysis of physical-mechanical properties of sediments in the central South Yellow Sea and Zhe-Min coastal area in China显示文摘The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min(Zhejiang Province to Fujian Province of China) coastal area. The results show that sediments in the two regions are both dominated by mud. There are perfect negative power function correlations between the water content and the density, the compression coefficient and the compression modulus; a good positive power function correlation between the liquid limit and the plastic limit, a perfect positive linear correlation between the water content and the void ratio, and a perfect polynomial function correlation between the miniature vane shear strength and the pocket penetration resistance. In general, compared with sediments in the Zhe-Min coastal area, sediments in the central South Yellow Sea possess high water content, high void ratio,low density, high plasticity, high compressibility, low shear strength. The causes of the differences between physical-mechanical properties of sediments are analyzed from the topographic features, material sources,hydrodynamic conditions, deposition rate, and material composition. Compared with the Zhe-Min coastal area,the central South Yellow Sea is far from the Mainland and low-lying; has poor hydrodynamic condition; the materials diffused to the area are less and dominated by fine clay, have the high content of smectite and organic matters. These factors lead to sediments of the central South Yellow Sea has the higher water content, the higher plasticity, the lower density, and the lower strength than sediments in the Zhe-Min coastal area. | XU Yuanqin LI Ping LI Peiying DU Jun LIU Lejun GAO Wei LIU Jie | 2017 | Acta Oceanologica Sinica2017，36，7： | 1 |
| 12 | Analysis of nucleosome positioning in promoters of miRNA genes and protein-coding genes显示文摘Nucleosome positioning in promoters is important for gene transcription regulation. In this paper, with a nucleosome prediction model, curvature profile, the characteristics of nucleosome positioning in promoters are analyzed for miRNA genes and protein-coding genes. In the vicinity of transcription start site (TSS), there is a nucleosome-free region (NFR) followed by a positioned nucleosome at ~200 bp downstream of TSS. A similar characteristic is observed in independent intronic promoters and intergenic promoters, namely, both types of promoters have a longer NFR in 0—-400 bp upstream of TSS. Moreover, transcription factor binding sites (TFBSs) locate in the NFR with a high concentration. However, nucleosome pattern in dependent intronic promoters are like that in protein-coding promoters, with two nucleosomes positioned at -200—-400 bp and -400—-600 bp upstream of TSS. The results indicate nucleosome positioning is probably different in independent miRNA promoters and protein-coding promoters; and positioning seems to be an important factor not only in regulation of protein-coding gene, but also in that of miRNA gene. | LIU HongDe ZHANG DeJin XIE JianMing YUAN ZhiDong MA Xin LU ZhiYuan GONG LeJun SUN Xiao | 2010 | Chinese Science Bulletin2010，55，22： | 1 |
| 13 | Stimulation mechanism of SDS nanoemulsion in fight gas reservoirs 显示文摘 | Luo Mingliang Liu Jialin Liao Lejun | 2012 | Advanced Materials Research2012，，418419420： | 1 |
| 14 | An integrated rice panicle phenotyping method based on X-ray and RGB scanning and deep learning显示文摘Rice panicle phenotyping is required in rice breeding for high yield and grain quality.To fully evaluate spikelet and kernel traits without threshing and hulling,using X-ray and RGB scanning,we developed an integrated rice panicle phenotyping system and a corresponding image analysis pipeline.We compared five methods of counting spikelets and found that Faster R-CNN achieved high accuracy(R~2 of 0.99)and speed.Faster R-CNN was also applied to indica and japonica classification and achieved 91%accuracy.The proposed integrated panicle phenotyping method offers benefit for rice functional genetics and breeding. | Lejun Yu Jiawei Shi Chenglong Huang Lingfeng Duan Di Wu Debao Fu Changyin Wu Lizhong Xiong Wanneng Yang Qian Liu | 2021 | The Crop Journal2021，9，1： | 1 |
| 15 | Panicle-3D: A low-cost 3D-modeling method for rice panicles based on deep learning, shape from silhouette, and supervoxel clustering显示文摘Self-occlusions are common in rice canopy images and strongly influence the calculation accuracies of panicle traits. Such interference can be largely eliminated if panicles are phenotyped at the 3 D level.Research on 3 D panicle phenotyping has been limited. Given that existing 3 D modeling techniques do not focus on specified parts of a target object, an efficient method for panicle modeling of large numbers of rice plants is lacking. This paper presents an automatic and nondestructive method for 3 D panicle modeling. The proposed method integrates shoot rice reconstruction with shape from silhouette, 2 D panicle segmentation with a deep convolutional neural network, and 3 D panicle segmentation with ray tracing and supervoxel clustering. A multiview imaging system was built to acquire image sequences of rice canopies with an efficiency of approximately 4 min per rice plant. The execution time of panicle modeling per rice plant using 90 images was approximately 26 min. The outputs of the algorithm for a single rice plant are a shoot rice model, surface shoot rice model, panicle model, and surface panicle model, all represented by a list of spatial coordinates. The efficiency and performance were evaluated and compared with the classical structure-from-motion algorithm. The results demonstrated that the proposed method is well qualified to recover the 3 D shapes of rice panicles from multiview images and is readily adaptable to rice plants of diverse accessions and growth stages. The proposed algorithm is superior to the structure-from-motion method in terms of texture preservation and computational efficiency. The sample images and implementation of the algorithm are available online. This automatic, cost-efficient, and nondestructive method of 3 D panicle modeling may be applied to high-throughput 3 D phenotyping of large rice populations. | Dan Wu Lejun Yu Junli Ye Ruifang Zhai Lingfeng Duan Lingbo Liu Nai Wu Zedong Geng Jingbo Fu Chenglong Huang Shangbin Chen Qian Liu Wanneng Yang | 2022 | The Crop Journal2022，10，5： | 1 |
| 16 | Geotechnical properties and stability of the submarine canyon in the northern South China Sea显示文摘The upper part of the continental slope in the northern South China Sea is prone to submarine landslide disasters,especially in submarine canyons.This work studies borehole sediments,discusses geotechnical properties of sediments,and evaluates sediment stability in the study area.The results show that sediment shear strength increases with increasing depth,with good linear correlation.Variations in shear strength of sediments with burial depth have a significantly greater rate of change in the canyon head and middle part than those in the canyon bottom.For sediments at the same burial depth,shear strength gradually increased and then decreased from the head to the bottom of the canyon,and has no obvious correlation with the slope angle of the sampling site.Under static conditions,the critical equilibrium slope angle of the sediments in the middle part of the canyon is 10°to 12°,and the critical slope angle in the head and the bottom of the canyon is 7°.The results indicate that potential landslide hazard areas are mainly distributed in distinct spots or narrow strips on the canyon walls where there are high slope angles. | Jie Liu Lejun Liu Ping Li Shan Gao Wei Gao Yuanqin Xu | 2019 | Acta Oceanologica Sinica2019，38，11： | 1 |
| 17 | The Belt and Road Initiative Leads to a Common Prosperity显示文摘In November 2016 at the 71st Session of the UN General Assembly,193 members unanimously agreed to include the Belt and Road Initiative into the UN General Assembly resolutions,calling on the international community to provide security assured environment for construction of the Belt and Road,which again confirms the | Wu Lejun Zhao Cheng Liu Rui | 2017 | Peace2017，，1： | 0 |
| 18 | Physical-mechanical properties of sediments and their correlation with near seafloor seismic amplitude in the Liwan canyon area, northern South China Sea显示文摘Before the implementation of offshore oil and gas exploitation,it is essential to understand the various factors that influence the stability of submarine sediments surrounding the project.Considering the factors such as cost and operability,it is not feasible to assess the physical-mechanical properties of sediments covering the entire region by borehole sampling.In this study,the correlation between near seafloor seismic amplitude and the mean shear strength of shallow sediments was explored using seismic and core testing data from the northern continental slope area of the South China Sea.Results showed that the mean water content of sediments in the layer up to 12 m below the seafloor(mbsf)gradually increased with increasing water depth,and the mean shear strength tended to decrease rapidly near the 1000 m depth contour.The near seafloor seismic amplitude could reflect the mean shear strength of sediments in the 12 mbsf layer under seismic frequency of 65 Hz and wave velocity of 1600 m/s.When the mean shear strength was greater than 10 kPa or the water depth was less than 1000 m,there was a significant linear positive correlation between mean shear strength and near seafloor seismic amplitude.Otherwise,there was a significant linear negative correlation between mean shear strength and near seafloor seismic amplitude.On the basis of these correlations,the pattern of shear strength was estimated from near seafloor seismic amplitude and mapped.The mean shear strength of sediments above 12 mbsf gradually decreased with increasing water depth in the continental slope area,whereas little change occurred in the continental shelf and the end of the canyon.Within the canyon area,the mean shear strength of sediments was characterized by larger values in both sides of the canyon walls and smaller values in the canyon bottom,which was consistent with the infinite slope stability theory.The study provides a method for using near seafloor seismic amplitude data to guide sediment sampling design,and presents a continuous dataset of sediment strength for the simulation of regional sediment stability. | Jie Liu Lejun Liu Ping Li | 2023 | Acta Oceanologica Sinica2023，42，5： | 0 |
| 19 | Highway Cost Prediction Based on LSSVM Optimized by Intial Parameters显示文摘The cost of highway is affected by many factors.Its composition and calculation are complicated and have great ambiguity.Calculating the cost of highway according to the traditional highway engineering estimation method is a completely tedious task.Constructing a highway cost prediction model can forecast the value promptly and improve the accuracy of highway engineering cost.This work sorts out and collects 60 sets of measured data of highway engineering;establishes an expressway cost index system based on 10 factors,including main route mileage,roadbed width,roadbed earthwork,and number of bridges;and processes the data through principal component analysis(PCA)and hierarchical cluster analysis.Particle swarm optimization(PSO)is used to obtain the optimal parameter combination of the regularization parameter c and the kernel function width coefficientin least squares support vector machine(LSSVM).Results show that the average relative and mean square errors of the PCA-PSO-LSSVM model are 0.79%and 10.01%,respectively.Compared with BP neural networks and unoptimized LSSVM model,the PCA-PSO-LSSVM model has smaller relative errors,better generalization ability,and higher prediction accuracy,thereby providing a new method for highway cost prediction in complex environments. | Xueqing Wang Shuang Liu Lejun Zhang | 2021 | Computer Systems Science & Engineering2021，36，1： | 0 |
| 20 | Teaching Design of Tourism Management Based on Information-based Teaching Method:A Case Study of Selection of Hotel Construction Site显示文摘Taking the knowledge points of hotel construction site selection as an example,this paper integrated the information-based teaching method with traditional classrooms.With the aid of virtual reality(VR)technology,the information-based teaching can turn the abstract knowledge into vivid knowledge.Using the Rain Classroom platform,teachers can communicate with students in a better manner.Combined with the powerful spatial data analysis function of geographic information system(GIS)software,it is intended to provide new ideas and perspectives for the effective integration of traditional teaching classrooms and information technology,and effectively apply them to the practical teaching process. | Haiyang MA Lejun LI Xiaomei LIU Weijun ZHAO Baoyi LOU | 2021 | Asian Agricultural Research2021，13，12： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员