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Effect of Wave Nonlinearity on the Instantaneous Seabed Liquefaction

China Ocean Engineering 2024年第1期38卷 93-103页

作者： WANG Zhao-jun SUI Ti-ti ZHANG Chi PAN Jun-ning Key laboratory of Port Waterway and Sedimentation Engineering of the Ministry of TransportNanjing Hydraulic Research InstituteNanjing 210024China Key laboratory of Coastal Disaster and Protection(Hohai University) Ministry of EducationNanjing 210098China The national Key laboratory of Water Disaster Prevention Nanjing 210098China

The nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal engineers.In this study,an analytical formula considering the nonlinear wave skewness and asymmetry is adopted to provide wave pressure on the seabed surface.The liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively characterize the nonlinear effect of wave on seabed liquefaction.Based on the 2D full dynamic model of wave-induced seabed response,a detailed parametric study is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed liquefaction.Further,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear wave.Results indicate that(1)Due to the influence of wave nonlinearity,the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity,the liquefaction depth of seabed decreases gradually.Especially under asymmetric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave conditions.However,highly skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)The asymmetry of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)Compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading.

关键词： nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction

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Comparison of clinical features and outcomes of proliferative,fibrotic,and mixed subtypes of IgG4-related disease:A retrospective cohort study

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Chinese Medical Journal 2024年第3期137卷 303-311页

作者： Linyi Peng Xinlu Zhang Jiaxin Zhou Jieqiong Li Zheng Liu Hui Lu Yu Peng Yunyun Fei Yan Zhao Xiaofeng Zeng Wen Zhang Department of Rheumatology and Clinical Immunology Peking Union Medical College HospitalNational Clinical Research Center for Dermatologic and Immunologic DiseasesState Key Laboratory of Complex Severe and Rare DiseasesThe Ministry of Education Key LaboratoryBeijing 100730China Institute of Clinical Medicine Peking Union Medical College Hospital(PUMCH)Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Background:Immunoglobulin G4-related disease(IgG4-RD)is a recently recognized immune-mediated disorder that can affect almost any organ in the human body.IgG4-RD can be categorized into proliferative and fibrotic subtypes based on patients’clinicopathological characteristics.This study aimed to compare the clinical manifestations,laboratory findings,and treatment outcomes of IgG4-RD among different subtypes.Methods:We prospectively enrolled 622 patients with newly diagnosed IgG4-RD at Peking Union Medical College Hospital from March 2011 to August 2021.The patients were divided into three groups according to their clinicopathological characteristics:proliferative,fibrotic,and mixed subtypes.We compared demographic features,clinical manifestations,organ involvement,laboratory tests,and treatment agents across three subtypes.We then assessed the differences in treatment outcomes among 448 patients receiving glucocorticoids alone or in combination with immunosuppressants.Moreover,risk factors of relapse were revealed by applying the univariate and multivariate Cox regression analysis.Results:We classified the 622 patients into three groups consisting of 470 proliferative patients,55 fibrotic patients,and 97 mixed patients,respectively.We found that gender distribution,age,disease duration,and frequency of allergy history were significantly different among subgroups.In terms of organ involvement,submandibular and lacrimal glands were frequently involved in the proliferative subtype,while retroperitoneum was the most commonly involved site in both fibrotic subtype and mixed subtype.The comparison of laboratory tests revealed that eosinophils(P=0.010),total IgE(P=0.006),high-sensitivity C-reactive protein(Psedimentation rate(P<0.001),complement C4(P<0.001),IgG(P=0.001),IgG1(P<0.001),IgG4(P<0.001),and IgA(P<0.001),at baseline were significantly different among three subtypes.Compared with proliferative and mixed subtypes,the fibrotic subtype showed the lowest rate of relapse(log-rank P=0.014).Conclus

关键词： IgG4-related disease Proliferative subtype Fibrotic subtype Clinical features Treatment outcome

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Effects of grass and shrub cover on the critical unit stream power in overland flow

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International Journal of Sediment Research 2011年第3期26卷 385-392页

作者： M.J.M.Rmkens usda-ars national sedimentation laboratory OxfordMississippiUSA.

Improved knowledge of the effects of grass and shrub cover in overland flow can provide valuable information for soil and water conservation programs.laboratory simulated rainfall studies were conducted to determine effects of grass and shrub on runoff and soil loss and to ascertain the relationship between the rate of soil loss and the unit stream power of runoff for a 20°slope subjected to rainfall intensities of 45,87,and 127 mm/h.The results indicated that the average runoff rates ranged from 4.2 to 73.1 mm/h for grass plots and from 9.3 to 58.2 mm/h for shrub plots.Runoff rates from shrub plots were less than those from grass plots for all but the 45 mm/h rainfall intensity regime. Average soil loss rates varied from 5.7 to 120.3 g/min.m~2 for grass plots and from 5.6 to 84.4 g/min.m~2 for shrub plots.Soil loss rates from shrub plots were generally lower than those from grass plots.Runoff and soil loss were strongly influenced by soil surface conditions due to the formation of erosion pits and rills.The rate of soil loss increased linearly with the unit stream power of runoff on both grass and shrub plots.Critical unit stream power values were 0.0127 m/s for grass plots and 0.0169 m/s for shrub plots.Shrub plots showed a greater stability to resist soil detachment and transport by surface flow than grass plots.

关键词： Soil erosion Soil loss Unit stream power

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Hydrocarbon Charging and Accumulation Process of the Large Bozhong19-6 Condensate Gas Reservoirs in the Southwestern Bozhong Sub-Basin,Bohai Bay Basin,China

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Journal of Earth Science 2024年第2期35卷 613-630页

作者： Quanyun Miao Changgui Xu Fang Hao Minjunshi Xie Qi Wang Jie Yin Huayao Zou General Prospecting Institute of China national Administration of Coal Geology Beijing100039China State Key laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing102249China Tianjin Branch of China national Offshore Oil Company Ltd. Tianjin300452China School of Geosciences China University of PetroleumQingdao266580China School of Geosciences Yangtze UniversityWuhan430100China

The Bozhong19-6(BZ19-6)condensate gas reservoirs,located in the southwestern Bozhong sub-basin,Bohai Bay Basin,China,were paleo-oil reservoirs in the geological past and have undergone at least three successive hydrocarbon charging events.The hydrocarbon migration and accumulation process of“early oil and late gas”has occurred in the current reservoirs.At the end of the sedimentation of the Guantao Formation(N_(1)g,∼12 Ma),the reservoirs began to fill with first stage low-moderate mature crude oil.At the late stage of the Lower Minghuazhen Formation(N_(1)ml)(∼6.7 Ma),the reservoirs were largely charged with second stage high mature crude oil.Since the deposition of the upper Minghuazhen Formation(N_(2)m^(u),∼5.1 Ma),the paleo-oil reservoirs were transformed into shallow Neogene reservoirs due to the reactivation of basement faults.From the late stage of the N_(2)m^(u)to the present day(∼2.8–0 Ma),the reservoirs were rapidly filled by natural gas within a short period.In addition,analysis of the formation of the reservoir bitumen and the conspicuous loss of the lower molecular weight n-alkanes in the crude oil reveal that the injection of a large amount of gas in the late stage caused gas flushing of the early charged oil.

关键词： Bohai Bay Basin BZ19-6 condensate gas reservoirs fluid inclusions hydrocarbon charging and accumulation petroleum geology

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Measurements of coupled fluid and sediment motion over mobile sand dunes in a laboratory flume

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International Journal of Sediment Research 2008年第4期23卷 329-337页

作者： Daniel G.WREN Roger A.KUHNLE Research Hydraulic Engineer USD A-ARS-National Sedimentation LaboratoryPh.D Research Hydraulic Engineer USD A-ARS-National Sedimentation Laboratory

The relationship between turbulent fluid motions and sediment particle motions over mobile sand dunes was investigated by using a laser Doppler velocimeter and an acoustic backscatter system in laboratory experiments performed at the usda-ars-national sedimentation laboratory. Profiles of acoustic backscatter from particles and at-a-point turbulence data were collected while translating both measurement devices downstream at the speed of mobile dune bedforms. The resulting data set was used to examine the frequency (recurrence frequency) at which the fluctuating backscatter and fluid velocity signals exceeded magnitude thresholds based on the standard deviation (σ) of the local velocity and the magnitude the acoustic signal resulting from backscatter from suspended particles. The slope of the downstream and vertical velocity recurrence frequencies generally indicated a gradually increasing recurrence time with increasing elevation. The recurrence frequency for acoustic backscatter data was not strongly variable with elevation. The closest correspondence between the recurrence frequencies of sediment backscatter and vertical velocities at the 1σ magnitude threshold was in a region defined by X/L<0.4 and y<6 cm. The downstream velocity was most closely related to backscatter in a small region at 0.4

关键词： Turbulence Suspended sediment Acoustic backscatter Dunes

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Effects of silt loading on turbulence and sand transport

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International Journal of Sediment Research 2012年第4期27卷 451-459页

作者： Daniel G.WREN Roger A.KUHNLE usda-Agricultural Research Service-national sedimentation laboratory

The transport of bed material and fluid turbulence are affected by many factors,including the fine sediment load being carried in a channel.Current research has focused on sand-sized particles introduced to gravel beds,while the effect of silt load on sand transport has received less attention. Experiments on the effects of silt load,in concentrations 0-26,900 mg l-1,on sand transport were performed with a recirculating laboratory flume using three different sand bed configurations:ripples （Fr=0.24）,dunes（Fr=0.34）,and dunes（Fr=0.48）.Three Acoustic Doppler Velocimeters were arranged to measure flow and turbulence quantities simultaneously in one vertical.Sand transport did not change in a consistent manner with increasing silt load,increasing up to 4,000 mg l-1for dunes （Fr=0.48） and up to 2,000 mg l-1for dunes（Fr=0.34） and then declining to near the clear water case with increasing silt concentrations.Silt addition for the ripple case caused a relatively small change in sand transport,decreasing with added silt up to approximately 2,000 mg l-1and then increasing as silt went up to approximately 10,000 mg l-1.Dunes（Fr=0.48） decreased in length and height as silt increased,while dunes（Fr=0.34） did not show a consistent trend.A clear trend of decreasing Reynolds stress with increasing silt concentration was observed in the ripple case,with a 33% reduction in near-bed Reynolds stress caused by an 8,900 mg l-1concentration of silt.

关键词： Turbulence modulation Bedforms Dunes Sand transport Silt loading

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Evolution of Cenozoic sedimentary architecture in Central and Southern South China Sea basins

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Journal of Palaeogeography 2024年第1期13卷 35-53页

作者： Wu Tang Xiao-Jun Xie Yi-Bo Wang Lian-Qiao Xiong Jia Guo Xin Li China national Offshore Oil Corporation Research Institute Beijing 100028China

The Central and Southern South China Sea(CSSCS) has a complex tectonic dynamic background and abundant oil and gas resources, which has always been a hot topic of academic and industrial attention.However, systematic analyses are still lacking regarding its sediment filling structure and evolution, mostly due to limited borehole penetration and poor quality of seismic reflection data for deeply buried sequences. No consensus has been reached yet on the sedimentary infilling processes, which impeded the reconstruction of the palaeogeography of Southeast Asia and the oil-and-gas exploration undertakings. Here, we illustrate the Cenozoic sedimentary evolution of the CSSCS region by synthesizing relevant data from previous literature and our own observations and displaying the evolution of depositional systems in sequential reconstructions. Besides, the controlling factors of preferred sedimentary scenarios in the CSSCS incorporate the latest interpretations of the spreading of South China Sea(SCS) as well as the demise of the hypothetical Proto-South China Sea(PSCS). The results show that there are three types of sedimentary basins in the CSSCS(foreland,strike-slip, and rift basins) with different sedimentary filling structures. The foreland basins formed a depositional pattern of ‘transition from deep water to shallow water environments', dominated by deep-water depositional systems which were formed before the Early Oligocene with submarine fans developed. Later,the foreland basins were gradually dominated by shallow-water depositional systems with deltas and shallow marine facies. The strike-slip basins showed the depositional architecture of ‘transition from lake to marine environments', i.e. the basins were dominated by lacustrine deposits during the Eocene and evolved into the marine depositional environment since Oligocene with delta developed in the western part of the basin. The depositional evolution of rift basins illustrated the characteristics of 'transition from clastic to carbonate deposits', i.e., th

关键词： Central and Southern South China Sea Sedimentary filling Main controlling factors Proto-South China Sea South China Sea

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The co-transport of Cd(Ⅱ) and nZnO in saturated soil packed column:effects of ionic strength and pH

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Acta Geochimica 2024年第1期43卷 97-109页

作者： Min Liao Guo Bin Yixin Luo Yuhao Zhang Kangyou Hu Xiongxiong Lu Xiaomei Xie College of Environmental and Resource Science Zhejiang UniversityYuhangtang Road No.866Hangzhou 310058China Zhejiang Provincial Key laboratory of Subtropical Soil and Plant Nutrition Yuhangtang Road No.866Hangzhou 310058China national Demonstration Center for Experimental Environmental and Resources Education(Zhejiang University) Yuhangtang Road No.866Hangzhou 310058China

The rapid development and widespread use of ZnO nanoparticles(nZnO) in various industries have raised concerns about their potential environmental impact.Therefore,understanding the fate and role of nZnO in the natural environment is crucial for mitigating their hazardous effects on the environment and human safety.The purpose of the present study was to provide scientific support for understanding and eliminating the joint risk of nanoparticle and heavy metal pollution in the soil environment by revealing the co-transport characteristics of Cd(Ⅱ) and ZnO nanoparticles(nZnO) in soil under different ionic strength(IS) and pH.The impacts of different IS and pH on the co-transport of Cd(Ⅱ) and nZnO in a20 cm long with an inner diameter of 2.5 cm acrylic column packed with 10 cm high soil samples were investigated in the present study.In the above system,a500 μg L^(-1) Cd(Ⅱ) loaded nZnO suspension pulse with varying IS or pH was introduced into the soil column for leaching over 5 PVs,followed up by 5 PVs background solutions without nZnO.The IS was 1,10,or 50 mM NaCl,with pH6,or the pH was 6,7 or 8 with 1 mM NaCl.Meanwhile,sedimentation experiments for nZnO,adsorption of Cd(Ⅱ) on soil,and nZnO,DLVO theory calculation for the same background condition were conducted.The presence of nZnO significantly increased the mobility of Cd(Ⅱ) as a result of its strong adsorption capacity for nZnO-associated Cd(Ⅱ).However,with the increase of IS,the co-transport of nZnO and Cd(Ⅱ) was decreased and the retention of nZnO in the soil column due to more nZnO attended to aggregate and sediment during the transport and the decrease in the adsorption capacity of nZnO for Cd(Ⅱ) by competition of Na^(+).When pH was 6,7,and 8,the co-transport of nZnO and Cd(Ⅱ) increased with higher pH due to the lower electrostatic attraction between nZnO and soil under higher pH.Meanwhile,the DLVO theory was fitted to describe the above co-transport process of nZnO and Cd(Ⅱ).More attention should be paid to the presence of nZnO on the migration of Cd(Ⅱ) i

关键词： ZnO Nanoparticles Cadimium Soil Co-transport

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Mitigation of atrazine,S-metolachlor,and diazinon using common emergent aquatic vegetation

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Journal of Environmental Sciences 2017年第6期29卷 114-121页

作者： Matthew T.Moore Martin A.Locke Robert Krǒger Water Quality and Ecology Research Unit USDA Agricultural Research ServiceNational Sedimentation LaboratoryOxfordMS 38655USA

By the year 2050, the population of the United States is expected to reach over 418 million, while the global population will reach 9.6 billion. To provide safe food and fiber, agriculture must balance pesticide usage against impacts on natural resources. Challenges arise when storms cause runoff to be transported to aquatic receiving systems. Vegetated systems such as drainage ditches and constructed wetlands have been proposed as management practices to alleviate pesticide runoff. Twelve experimental mesocosms （1.3 ±0.71 ± 0.61 m） were filled with sediment and planted with a monoculture of one of three wetland plant species （Typha latifolia, Leersia oryzoides, and Sparganium arnericanurn）. Three mesocosms remained unvegetated to serve as controls. All mesocosms were amended with 9.2 ± 0.8 μg/L, 12 ± 0.4 μg/L, and 3.1 ± 0.2 μg/L of atrazine, metolachlor, and diazinon, respectively, over a 4 hr hydraulic retention time to simulate storm runoff. Following the 4 hr amendment, non-amended water was flushed through mesocosms for an additional 4 hr. Outflow water samples were taken hourly from pre-amendment through 8 hr, and again at 12, 24, 48, 72, and 168 hr post-amendment. L. oryzoides and T. latifolia had mean atrazine, metolachlor, and diazinon retentions from B1%-55% for the first 4 hr of the experiment. Aside from S. arnericanum and atrazine （25% retention）, unvegetated controls had the lowest pesticide retention （17%-28%） of all compared mesocosms. While native aquatic vegetation shows promise for mitigation of pesticide runoff, further studies increasing the hydraulic retention time for improved efficiency should be examined.

关键词： Phytoremediation Pesticide Mesocosm Wetland

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Cretaceous integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1229-1289页

作者： Dangpeng XI Guobiao LI Shijun JIANG Xin RAO Tian JIANG Tianyang WANG Zuohuan QIN Yasu WANG Jianzhong JIA Muhammad KAMRAN Zhongye SHI Yuyang WU Panxi WANG Lixin SUN Qinggao ZENG Xiaoqiao WAN State Key laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China College of Oceanography Hohai UniversityNanjing 213200China Key laboratory of Palaeobiology and Petroleum Stratigraphy Nanjing Institute of Geology and PaleontologyChinese Academy of SciencesNanjing 210008China State Key laboratory of Tibetan Plateau Earth System Environmentand Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China China national Offshore Oil Corporation Limited Beijing 100028China Shanghai Science and Technology Museum Shanghai 200120China Xizang Bureau of Geological and Mineral Exploration and Development Lhasa 850000China Tianjin Geological Survey Center of China Geological Survey Tianjin 300170China

The Cretaceous Period is a vital time interval in deciphering the evolutionary history of the Neo-Tethys Ocean and the convergence of different plates and blocks across the Qinghai-Tibetan Plateau.A detailed stratigraphic framework and paleogeographic patterns are the basis for understanding the evolution of the Neo-Tethys Ocean and the formation of the QinghaiTibetan Plateau.Here,the Cretaceous stratigraphy,biota,paleogeography,and major geological events in the Qinghai-Tibetan Plateau are analyzed to establish an integrative stratigraphic framework,reconstruct the paleogeography during the Cretaceous Period,and decode the history of the major geological events.The Cretaceous rocks of the Qinghai-Tibetan Plateau and its surrounding area are predominantly marine deposits,with a small amount of interbedded marine-terrestrial and terrestrial conponents.The Indus-Yarlung Tsangpo Suture Zone was responsible for the deposition of deep marine sediments dominated by ophiolite suites and radiolarian silicalite.To the south,the Tethys Himalayas and Indus Basin received marine sediments of varying depths and lithology;to the north,the Xigaze and Ladakh forearc basins are also filled with marine sediments.The Lhasa Block,Karakorum Block,western Tarim Basin,and West Burma block consist of shallow marine,interbedded marine-terrestrial,and terrestrial sediments.The Qiangtang Basin and other areas are dominated by terrestrial sedimentation.The Cretaceous strata of the Qinghai-Tibetan Plateau and its surrounding areas are widely distributed and diversified,with abundant foraminifera,calcareous nannofossils,radiolarians,ammonites,bivalves,and palynomorphs.On the basis of integrated lithostratigraphic,biostratigraphic,geochronologic,and chemostratigraphic analyses,we proposed herein a comprehensive stratigraphic framework for the Cretaceous Period of the eastern Neo-Tethys.By analyzing the Cretaceous biota of different biogeographic zones from eastern Neo-Tethys and its surrounding areas,we reconstructed the paleobiogeography of d

关键词： Qinghai-Tibetan Plateau Tethys Cretaceous Stratigraphy Biota Paleogeography

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