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Critical State Sedimentation Line of Soft Marine Clays 被引量:1
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作者 洪振舜 刘汉龙 CHANG Nien-yin 《China Ocean Engineering》 SCIE EI 2003年第4期631-640,共10页
The compression behavior responsible for unity sensitivity is very valuable in quantitative assessment of the effects of soil structure on the compression behavior of soft marine sediments. However, the quantitative a... The compression behavior responsible for unity sensitivity is very valuable in quantitative assessment of the effects of soil structure on the compression behavior of soft marine sediments. However, the quantitative assessment of such effects is not possible because of unavailability of the formula for the compression curve of marine sediments responsible for unit sensitivity. In this study, the relationship between the remolded state and the conventional critical state line is presented in the deviator stress versus mean effective stress plot. The analysis indicates that the remolded state is on the conventional critical state line obtained at a relatively small strain. Thus, a unique critical state sedimentation line for marine sediments of unit sensitivity is proposed. The comparison between the critical state sedimentation line proposed in this study and the existing normalized consolidation curves obtained from conventional oedometer tests on remolded soils or reconstituted soils explains well the 展开更多
关键词 conventional critical state line critical state sedimentation line initial water content liquid limit marine sediments ocean wave action remolded state
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Influence of Cathode Modification by Chitosan and Fe^(3+)on the Electrochemical Performance of Marine Sediment Microbial Fuel Cell
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作者 ZAI Xuerong GUO Man +4 位作者 HUANG Xiang ZHANG Huaijing CHEN Yan JI Hongwei FU Yubin 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第3期709-716,共8页
The electrochemical performances of cathode play a key role in the marine sediment microbial fuel cells(MSMFCs)as a long lasting power source to drive instruments,especially when the dissolved oxygen concentration is ... The electrochemical performances of cathode play a key role in the marine sediment microbial fuel cells(MSMFCs)as a long lasting power source to drive instruments,especially when the dissolved oxygen concentration is very low in seawater.A CTS-Fe^(3+)modified cathode is prepared here by grafting chitosan(CTS)on a carbon fiber surface and then chelating Fe^(3+)through the coordination process.The electrochemical performance in seawater and the output power of the assembled MSMFCs are both studied.The results show that the exchange current densities of CTS and the CTS-Fe^(3+)group are 5.5 and 6.2 times higher than that of the blank group,respectively.The potential of the CTS-Fe^(3+)modified cathode increases by 138 mV.The output power of the fuel cell(613.0 mW m^(-2))assembled with CTS-Fe^(3+)is 54 times larger than that of the blank group(11.4 mW m^(-2))and the current output corresponding with the maximum power output also increases by 56 times.Due to the valence conversion between Fe^(3+)and Fe^(2+)on the modified cathode,the kinetic activity of the dissolved oxygen reduction is accelerated and the depolarization capability of the cathode is enhanced,resulting higher cell power.On the basis of this study,the new cathode materials will be encouraged to design with the complex of iron ion in natural seawater as the catalysis for oxygen reduction to improve the cell power in deep sea. 展开更多
关键词 marine sediments microbial fuel cell chitosan and iron chelation modified cathode electrochemical performance power output
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Heavy metal pollution assessment in marine sediments in the Northwest coast of Sabah,Malaysia
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作者 Sin-Yi Ling Asis Junaidi +1 位作者 Abdullah Mohd-Harun Musta Baba 《China Geology》 CAS CSCD 2023年第4期580-593,共14页
Heavy metal contents along the Northwest coast of Sabah were determined to interpret the pollution level in the marine sediment. The metal abundance is regulated by the physico-chemical properties such as the average ... Heavy metal contents along the Northwest coast of Sabah were determined to interpret the pollution level in the marine sediment. The metal abundance is regulated by the physico-chemical properties such as the average sediment pH(7.82, 9.00 and 8.99), organic matter(0.62%, 1.60%, and 2.27%), moisture content(25.00%, 29.70%, and 15.00%) and sandy texture in Kota Belud, Kudat and Mantanani Island,respectively. The major elements show Ca>Fe>Mg>Al>Mn for all study sites, while the heavy metals show Ni>Cr>Zn>Cu>Co>Pb, Cr>Ni>Zn>Cu>Pb>Co and Zn>Pb>Cr>Ni, for Kota Belud, Kudat and Mantanani Island, respectively. The pollution degree of heavy metals was evaluated by using the Sediment Quality Assessment(SQA). The SQA parameters indicated none to moderate pollution in Kota Belud that shows Class 0, Class 1 and Class 2 pollution. The parameters also indicated none to low pollution in Kudat and Mantanani Island that show only Class 0 pollution. The enrichment factor(EF) suggested minor to moderately severe metal enrichment by anthropogenic sources in Kota Belud, whereas only minor enrichment in Kudat and Mantanani Island. The modified pollution degree(MCD<1.5) and pollution load index(0 PLI<1) indicating only low pollution level in the marine sediments for all study sites. The objectives of this study are:(1) to determine the physico-chemical parameters of sediments,(2) interpret the heavy metal contents and(3) evaluate the sediment quality. 展开更多
关键词 Physico-chemical properties Sediment quality Major elements Heavy metal pollution Ni-Cr-Zn-Cu-Co-Pb pollution marine sediment COASTLINE
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A simple guideline to apply excitation-emission matrix spectroscopy(EEMs)for the characterization of dissolved organic matter(DOM)in anoxic marine sediments
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作者 Shuchai Gan Verena BHeuer +2 位作者 Frauke Schmidt Lars Wörmer Kai-Uwe Hinrichs 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第1期109-119,共11页
Marine sediments represent a major carbon reservoir on Earth.Dissolved organic matter(DOM)in pore waters accumulates products and intermediates of carbon cycling in sediments.The application of excitation-emission mat... Marine sediments represent a major carbon reservoir on Earth.Dissolved organic matter(DOM)in pore waters accumulates products and intermediates of carbon cycling in sediments.The application of excitation-emission matrix spectroscopy(EEMs)in the analysis of subseafloor DOM samples is largely unexplored due to the redox-sensitive matrix of anoxic pore water.Therefore,this study aims to investigate the interference caused by the matrix on EEMs and propose a guideline to prepare pore water samples from anoxic marine sediments.The parameters determined by fluorescence spectra include 3D-index derived from EEMs after parallel factor analysis(PARAFAC),fluorescence index(FI)(contribution of terrigenous DOM),biological index(BIX)and humification index(HIX)derived from 2D emission spectra.First,we investigated the impacts of extensively-presented ions as typical electron acceptors,which are utilized by anaerobic microbes and stratified in marine sediments:Fe(II),Fe(III),Mn(II)and sulfide in anoxic pore water resulted in biases of fluorescent signals.We proposed threshold concentrations of these ions when the interference on EEMs occurred.Effective removal of sulfide from sulfide-rich samples could be achieved by flushing with N_(2)for 2 min.Second,the tests based on DOM standard were further verified using pristine samples from marine sediments.There was a significant change in the fluorescence spectra of DOM in anoxic sediments from the Rhône Delta.This study demonstrated that the change was caused by oxidation of the matrix rather than the intrinsic alteration of DOM.It was confirmed by extracted DOM via both EEMs analysis and Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).Slight oxidation of sulfur-containing compounds(e.g.,sulfhydryl)and polyphenol-like compounds occurred.Finally,a sample preparation sequence is proposed for pore water from anoxic sediments.This method enables measurement with small volumes of the sample(e.g.,50µL in this study)and ensures reliable data without the interference of the redox-sensitive matrix.This study provides access to the rapid analysis of DOM composition in marine sediments and can potentially open a window into examining the carbon cycling of the marine deep biosphere. 展开更多
关键词 marine subsurface sediment EEMs PARAFAC FT-ICR-MS anaerobic pore water
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Fine Sand and Clay Sediment Acoustic Properties of the Novel Sediment Sample from the Arabian Sea:Experimental Investigations and Biot−Stoll Model Validation
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作者 Shahabuddin SHAIKH HUANG Yi-wang +1 位作者 ZHANG Ze-chuan Habib Hussain ZUBERI 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期169-180,共12页
The present study explores the physical and acoustic characteristics of fine sand and clay in novel seabed marine sediments from of Pakistan coastline of the Arabian Sea.The measured physical parameters included mean ... The present study explores the physical and acoustic characteristics of fine sand and clay in novel seabed marine sediments from of Pakistan coastline of the Arabian Sea.The measured physical parameters included mean grain size,mass density,bulk density,salinity,porosity,permeability,pore size and mineralogical composition.Acoustic properties,including sound speed and attenuation,in the high frequency range of 90-170 kHz were analyzed.A controlled laboratory setup with the acoustic transmission method and Fourier transform techniques was utilized to examine the sound propagation and absorption of novel seabed sediments.The standard deviation of mean sound speed in fresh water was 0.75 m/s,and attenuation was observed in the range of 0.43 to 0.61 dB/m.The mean sound velocity in sand and clay varied from 1706 to 1709 m/s and 1602 to 1608 m/s,respectively.Corresponding average attenuation was observed at 80 to 93 dB/m in sandy sediments and from 31.8 to 38.6 dB/m in clayey sediments.Sound velocity variation within sandy sediment is low,consistent with expected results,and smaller than the predicted uncertainty.However,clay sediment exhibited a positive linear correlation and low sound speed variation.Attenuation increased linearly with frequency for both sediments.Finally,the laboratory results were validated by using the Biot−Stoll model.The dispersion of sound speed in sandy and clayey sediments was consistent with the predictions of the Biot−Stoll model.Measured attenuation aligned more with Biot−Stoll model predictions due to improved permeability,tortuosity and pore size parameter fitting. 展开更多
关键词 physical and acoustic characteristics marine sediments sound speed ATTENUATION Biot−Stoll model
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Tetrabromobisphenol A and hexabromocyclododecane in sediments from the Zhujiang(Pearl) River Estuary and South China Sea
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作者 Chuyue Long Weiyan Yang +6 位作者 Jiaxun Lu Yuanyue Cheng Ning Qiu Sen Du Li Zhang Shejun Chen Yuxin Sun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期32-37,共6页
Marine sediments collected from the Zhujiang(Pearl) River Estuary(ZRE) and South China Sea(SCS) were utilized to study the occurrence and spatial distribution of tetrabromobisphenol A(TBBPA) and hexabromocyclododecane... Marine sediments collected from the Zhujiang(Pearl) River Estuary(ZRE) and South China Sea(SCS) were utilized to study the occurrence and spatial distribution of tetrabromobisphenol A(TBBPA) and hexabromocyclododecane(HBCDD).The levels of TBBPA and HBCDD in sediments ranged from not detected(nd) to 6.14 ng/g dry weight(dw) and nd to 0.42 ng/g dw.TBBPA concentrations in marine sediments were substantially higher than HBCDD.The concentrations of TBBPA and HBCDD in the ZRE sediments were significantly greater than those in the SCS.α-HBCDD(48.7%) and γ-HBCDD(46.2%) were the two main diastereoisomers of HBCDD in sediments from the ZRE,with minor contribution of β-HBCDD(5.1%).HBCDD were only found in one sample from the northern SCS.The enantiomeric fraction of α-HBCDD in sediments from the ZRE was obviously greater than 0.5,indicating an accumulation of(+)-α-HBCDD.The enantiomers of HBCDD were not measured in sediments from the SCS.This work highlighted the environmental behaviors of TBBPA and HBCDD in marine sediments. 展开更多
关键词 tetrabromobisphenol A HEXABROMOCYCLODODECANE marine sediments Zhujiang River Estuary South China Sea
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Determination of Lignin in Marine Sediment Using Alkaline Cupric Oxide Oxidation-Solid Phase Extraction-on-Column Derivatization-Gas Chromatography 被引量:10
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作者 ZHANG Ting LI Xianguo +3 位作者 SUN Shuwen LAN Haiqing DU Peirui WANG Min 《Journal of Ocean University of China》 SCIE CAS 2013年第1期63-69,共7页
Lignin serves as one of the most important molecular fossils for tracing Terrestrial Organic Matters (TOMs) in marine environment. Extraction and derivatization of lignin oxidation products (LOPs) are crucial for ... Lignin serves as one of the most important molecular fossils for tracing Terrestrial Organic Matters (TOMs) in marine environment. Extraction and derivatization of lignin oxidation products (LOPs) are crucial for accurate quantification of lignin in marine sediment. Here we report a modification of the conventional alkaline cupric oxide (CuO) oxidation method, the modification consisting in a solid phase extraction (SPE) and a novel on-column derivatization being employed for better efficiency and reproducibility. In spiking blanks, recoveries with SPE for the LOPs are between 77.84% and 99.57% with relative standard deviations (RSDs) ranging from 0.57% to 8.04% (n=3), while those with traditional liquid-liquid extraction (LLE) are from 44.52% to 86.16% With RSDs being from 0.53% to 13.14% (n=3). Moreover, the reproducibility is greatly improved with SPE, with less solvent consumption and shorter processing time. The average efficiency of on-column derivatization for LOPs is 100.8%±0.68%, which is significantly higher than those of in-vial or in-syringe derivatization, thus resulting in still less consumption of derivatizing reagents.Lignin in the surface sediments sampled from the south of Yangtze River estuary, China, was determined with the established method. Recoveries of 72.66% to 85.99% with standard deviation less than 0.01mg/10g dry weight are obtained except for p-hydroxybenzaldehyde. The lignin content ∑8 (produced from 10g dry sediment) in the research area is between 0.231 and 0.587mg. S/V and C/V ratios (1.028 ± 0.433 and 0.192±0.066, respectively) indicate that the TOMs in this region are originated from a mixture of woody and nonwoody angiosperm plants; the high values or (Ad/Al)v suggest that the TOMs has been highly degraded. 展开更多
关键词 LIGNIN alkaline cupric oxide SPE on-column derivatization marine sediments
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Rare earth elements distribution in marine sediments of Malaysia coasts 被引量:11
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作者 Rezaee Ebrahim Saraee Khadijeh Saion B.Elias +1 位作者 Abdul Khalik Wood Abdi Mohammad Reza 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第6期1066-1071,共6页
In the east coast Peninsular Malaysia region,sediments are transported by several rivers from the east Malaysia into the South China Sea estuary.In the vicinity of the five river estuaries core sediments were collecte... In the east coast Peninsular Malaysia region,sediments are transported by several rivers from the east Malaysia into the South China Sea estuary.In the vicinity of the five river estuaries core sediments were collected in order to investigate rare earth elements(REEs) profile.Core sediments were divided into strata of between 2 to 4 cm intervals and prepared for analyzing by ICP-AES.REE concentrations of 54.3 μg/gr at 24–26 cm in EC4 increased to 114.1 μg/gr at 20–22 cm in EC5.The measured concentration of ... 展开更多
关键词 enrichment factor rare earth elements marine sediments South China Sea shale average
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Impact of anions on the heavy metals release from marine sediments 被引量:7
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作者 ZHONG Ai-ping GUO Shu-hai +2 位作者 LI Feng-mei LI Gang JIANG Ke-xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1216-1220,共5页
Marine sediments from Lianshan Bay in Huludao, China, were studied in laboratory. A series of simulated experiments were carried out to investigate the influences of three kinds of anions CL^-, SO4^2- and HCO3^- on th... Marine sediments from Lianshan Bay in Huludao, China, were studied in laboratory. A series of simulated experiments were carried out to investigate the influences of three kinds of anions CL^-, SO4^2- and HCO3^- on the release ofCd, Pb, Cu and Zn from the sediments. The results showed that the sequences about the impact of the three anions were Cl^-〉HCO3^-〉SO4^2+. The release potential of heavy metals in the presence of each anions was in the following order: Cd≥Cu 〉Zn≈Pb. The correlations were positive between CI content and the quantity of Cd released from the marine sediment, whereas there was no significant relationship between CI content and amount of Cu and Zn released. For SO4^2- and HCO3^-, the release of the heavy metals from marine sediments was not obvious. 展开更多
关键词 marine sediments ANIONS heavy metals RELEASE
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Geochemical analysis of marine sediments using fused glass disc by X-ray fluorescence spectrometry 被引量:7
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作者 夏宁 张勤 +1 位作者 姚德 李国会 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第4期475-479,共5页
A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sedim... A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sediment samples using fused glass disc by X-ray Fluorescence spectrometry. Calibration was made using marine sediment certified reference materials and the synthetic standard samples prepared by mixing several marine sediments with stream sediment and carbonate standard samples in different proportions. The matrix effect was corrected using theoretical alpha coefficients, experience coefficients and the scattered radiation as the internal standard (for the trace elements). The accuracy of the method was evaluated by analysis of certified reference materials GBW07314, GBW07334 and GSMS6. The results are in good agreement with the certified values of the standards with RSD less than 2.60%, except for Y, Cr, Ga, Ce, La, Nb, Rb, and V with RSD less than 9.0% (n=12). 展开更多
关键词 marine sediment X-ray fluorescence spectrometry geochemical analysis multi-element analysis
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Denitrification and Nitrate Reduction to Ammoniumin Taihu Lake and Yellow Sea Inter-Tidal MarineSediments 被引量:5
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作者 YINSHIXUE SHENQIRONG 《Pedosphere》 SCIE CAS CSCD 1999年第4期305-309,共5页
Denitrification and nitrate reduction to ammonium in Taihu Lake and Yellow Sea inter-tidal marinesediments were studied. The sediment samples were made into slurry containing 150 g dry matter per liter.Various amounts... Denitrification and nitrate reduction to ammonium in Taihu Lake and Yellow Sea inter-tidal marinesediments were studied. The sediment samples were made into slurry containing 150 g dry matter per liter.Various amounts of glucose and 5 mmol L-1 of potassium nitrate were added in order to achieve differentratios of glucose-C to nitrate-N. Acetylene inhibition technique was applied to measure denitrification in theslumes. All samples were incubated anaerobically under argon atmosphere. Data showed that Taihu Lakesediment produced more N2O than marine sediment. Denitrification potential was higher in Taihu Lakesediment than in marne one. Glucose added increased denitrification activity but not the denitrification po-tential of the sediments. Dissimilatory nitrate reduction to ammonium seemed to occur in marine sediment,but not in freshwater one. When the marine sediment was treated with 25 mmol L-1 glucose, its denitrification poteatial, as indicated by maximum N2O production by acetylene blockage, was lower than that treatedwith no or 2.5 mmol L-l glucose. Acetylene was suspected to have inhibitory effect on dissimilatory nitratereduction to ammonium. 展开更多
关键词 DENITRIFICATION dissimilatory nitrate reduction to ammonium marine sediment Taihu Lakesediment
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Dynamic shear modulus and damping ratio characteristics of undisturbed marine soils in the Bohai Sea,China 被引量:5
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作者 Zhang Yan Zhao Kai +1 位作者 Peng Yanjv Chen Guoxing 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第2期297-312,共16页
This paper presents results from a series of stress-controlled undrained cyclic triaxial tests on the undisturbed marine silty clay,silt,and fine sand soils obtained from the Bohai Sea,China.Emphasis is placed on the ... This paper presents results from a series of stress-controlled undrained cyclic triaxial tests on the undisturbed marine silty clay,silt,and fine sand soils obtained from the Bohai Sea,China.Emphasis is placed on the major factors for predominating the dynamic shear modulus(G)and damping ratio(λ)in the shear strain amplitude(γ_(a))from 10^(-5) to 10^(-2),involving depth,sedimentary facies types,and water content of marine soils.The empirical equations of the small-strain shear modulus(G_(max))and damping ratio(λ_(min))using a single-variable of depth H are established for the three marine soils.A remarkable finding is that the curves of shear modulus reduction(G/G_(max))and the damping ratio(λ)with increasing γ_(a) of the three marine soils can be simply determined through a set of explicit expressions with the two variables of depth H and water content W.This finding is validated by independent experimental data from the literature.At the similar depths,the G value of the marine soils of terrestrial facies is the largest,followed b_(y) the neritic facies,and the G value of the marine soils of abyssal facies is the smallest.The sedimentary facies types of the marine soils have slight effect on theλvalue.Another significant finding is that the shear modulus reduction curves plotted against the γ_(a) of the three marine soils at the similar depths are significantly below those of the corresponding terrigenous soils,while the damping curves plotted against γ_(a) are just the opposite.The results presented in this paper serve as a worthful reference for the evaluation of seabed seismic site effects in the Bohai Sea due to lack of experimental data. 展开更多
关键词 Bohai Sea marine sediments dynamic shear modulus damping ratio sedimentary facies
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Development of in-situ Marine Sediment Geo-Acoustic Measurement System with Real-Time and Multi Frequencies (the Second Generation) 被引量:6
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作者 陶春辉 邓显明 +6 位作者 李红星 周建平 金肖兵 傅顺声 Wlkens R. H 顾春华 何拥华 《China Ocean Engineering》 SCIE EI 2009年第4期769-778,共10页
Compared with the laboratory acoustic measurement of sediment samples, the in-situ acoustic measurement in marine sediment is considered more accurate and rehable, because it covers all of the surrounding environment ... Compared with the laboratory acoustic measurement of sediment samples, the in-situ acoustic measurement in marine sediment is considered more accurate and rehable, because it covers all of the surrounding environment factors and avoids the disturbance during the course of sampling and transporting of sediment samples. A new multi-frequency in-situ geoacoustic measurement system (MFIS^AMS) has been developed. The system can provide acoustic vdocity (compressional wave) and attenuation profiles of the uppermost 4 - 8 m sediment in the seafloor. It consists of 8 channels with 12 frequencies (multi-frequencies) and 0.5 - 2 MHz sampling rates. The data collected can be transmiuted in real-time. Associated with inclinometer and altimeter, it can provide the data for depth emendation. Acoustic velocity and attenuation data have been obtained from two in-situ experiments conducted in the Hangzhou Bay. 展开更多
关键词 marine sediment in-situ acoustic measurement acoustic velocity and attenuation
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Application of confocal laser Raman spectroscopy on marine sediment microplastics 被引量:4
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作者 LIU Jing ZHANG Xin +6 位作者 DU Zengfeng LUAN Zhendong LI Lianfu XI Shichuan WANG Bing CAO Lei YAN Jun 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第5期1502-1516,共15页
Marine sediment is the primary sink of microplastics and is an indicator of pollution levels.However,although there are well-developed detection methods,detection is rarely focused on lowmicrometer-sized particles,mai... Marine sediment is the primary sink of microplastics and is an indicator of pollution levels.However,although there are well-developed detection methods,detection is rarely focused on lowmicrometer-sized particles,mainly due to technique limitations.In this study,a simplifi ed process omitting digestion procedures was developed to pretreat microplastics obtained from marine sediment and was coupled with micro-Raman spectroscopy to identify microplastics.Based on the overall analysis of the characteristic peak assignments,a Raman spectral reference library was constructed for 18 types of plastic.In addition,the eff ects of the measurement parameters were systematically described.Field research was then conducted to validate the developed process and investigate microplastic contamination in Huiquan Bay,Qingdao,China.This simplifi ed process could retain the original appearance of microparticles and accomplish the detection of<500μm-sized microplastics in environmental samples.Microplastics in the size range of 10-150μm accounted for 76%of all microplastics,and 56%of the total particles was particles smaller than 50μm.Polypropylene(42%)and polyethylene(20%)were predominant components of the particles.In particular,polypropylene particles smaller than 10μm were identifi ed in marine sediment.This work demonstrates that Raman spectroscopy is not only an eff ective tool for detecting environmental particles but also highly applicable for identifying particles extracted from marine sediment. 展开更多
关键词 microplastics CONFOCAL Raman spectroscopy marine sediment
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Pitfalls of acid leaching method for determining organic and inorganic carbon contents in marine sediments 被引量:2
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作者 Chen Ling Zhifei Liu +3 位作者 Jingwen Zhang Yulong Zhao Yanwei Zhang Adrian RFernandez 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第8期96-102,共7页
Organic and inorganic carbon contents of marine sediments are important to reconstruct marine productivity,global carbon cycle, and climate change. A proper method to separate and determine organic and inorganic carbo... Organic and inorganic carbon contents of marine sediments are important to reconstruct marine productivity,global carbon cycle, and climate change. A proper method to separate and determine organic and inorganic carbons is thus of great necessity. Although the best method is still disputable, the acid leaching method is widely used in many laboratories because of its ease-of-use and high accuracy. The results of the elemental analysis of sediment trap samples reveal that organic and inorganic carbon contents cannot be obtained using the acid leaching method, causing an infinitely amplified error when the carbon content of the decarbonated sample is 12%±1% according to a mathematical derivation. Acid fumigation and gasometric methods are used for comparison, which indicates that other methods can avoid this problem in organic carbon analysis. For the first time, this study uncovers the pitfalls of the acid leaching method, which limits the implication in practical laboratory measurement, and recommends alternative solutions of organic/inorganic carbon determination in marine sediments. 展开更多
关键词 marine sediments organic carbon inorganic carbon acid leaching method LIMITATION
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Determination of Trace Germanium in Marine Sediments by Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS) 被引量:2
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作者 LIJing ZHAOShilan +1 位作者 ZHANGZhaohui ZENGXianjie 《Journal of Ocean University of China》 SCIE CAS 2004年第2期179-182,共4页
A method for the analysis of trace germanium in marine sediments by HG-AFS has been investigated. The experimental conditions such as the acidity of reduction reaction, the amount of sodium boro-hydride, the carrier g... A method for the analysis of trace germanium in marine sediments by HG-AFS has been investigated. The experimental conditions such as the acidity of reduction reaction, the amount of sodium boro-hydride, the carrier gas flow rate, etc., were tested and optimized by using a kind of orthogonal design. The detection limit of the presented method is 0.95 μg L -1 for germanium. The calibration curve shows a satisfactory line in the concentration range 0-320 μg L -1 Ge with a variation coefficient of ±2.1%. 展开更多
关键词 hydride generation-atomic fluorescence spectrometry (HG-AFS) GERMANIUM marine sediment TRACE
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Engineering and microstructure properties of contaminated marine sediments solidified by high content of incinerated sewage sludge ash 被引量:2
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作者 Jiang-Shan Li Yifan Zhou +4 位作者 Xin Chen Qiming Wang Qiang Xue Daniel C.W.Tsang Chi Sun Poon 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第3期643-652,共10页
Management of incinerated sewage sludge ash(ISSA)and dredged contaminated marine sediments(CMSs)is a great challenge for Hong Kong and other coastal cities due to limited landfilling capacity.The present study investi... Management of incinerated sewage sludge ash(ISSA)and dredged contaminated marine sediments(CMSs)is a great challenge for Hong Kong and other coastal cities due to limited landfilling capacity.The present study investigates the use of high content(20%of sediment by mass)of ISSA in combination with cement/lime for solidification/stabilization(S/S)treatment of CMSs to provide a way to reuse the wastes as construction materials.The results showed that ISSA being a porous material was able to absorb a large amount of water rendering a more efficient solidification process of the marine sediment which normally had a very high water content(w80%).The S/S treatment improved the engineering properties of the sediment,but reduced the workability,especially for the lime-treated samples.Lime can be used to replace ordinary Portland cement(OPC)for better heavy metal immobilization and carbon emission reduction.The hardened sediment samples prepared with 10%of lime and 20%of ISSA could attain a strength of 1.6 MPa after 28 d of curing.In addition,leaching tests confirmed that there was no environmental risk induced by these stabilized materials.The formation of hydrated cementitious compounds including calcium silicate hydrate(CeSeH)/calcium aluminate silicate hydrate(C-A-S-H)/hydrocalumite/calcite was mainly responsible for the strength development in the ISSA/lime-treated sediments. 展开更多
关键词 Contaminated marine sediment(CMS) Incinerated sewage sludge ash(ISSA) Solidification/stabilization(S/S) Heavy metals Construction material
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An improved method for quantitatively measuring the sequences of total organic carbon and black carbon in marine sediment cores 被引量:1
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作者 徐小明 祝青 +3 位作者 周芊至 刘金钟 袁建平 王江海 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第1期105-113,共9页
Understanding global carbon cycle is critical to uncover the mechanisms of global warming and remediate its adverse ef fects on human activities.Organic carbon in marine sediments is an indispensable part of the globa... Understanding global carbon cycle is critical to uncover the mechanisms of global warming and remediate its adverse ef fects on human activities.Organic carbon in marine sediments is an indispensable part of the global carbon reservoir in global carbon cycling.Evaluating such a reservoir calls for quantitative studies of marine carbon burial,which closely depend on quantifying total organic carbon and black carbon in marine sediment cores and subsequently on obtaining their high-resolution temporal sequences.However,the conventional methods for detecting the contents of total organic carbon or black carbon cannot resolve the following specific difficulties,i.e.,(1)a very limited amount of each subsample versus the diverse analytical items,(2) a low and fluctuating recovery rate of total organic carbon or black carbon versus the reproducibility of carbon data,and(3)a large number of subsamples versus the rapid batch measurements.In this work,(i)adopting the customized disposable ceramic crucibles with the microporecontrolled ability,(ii)developing self-made or customized facilities for the procedures of acidification and chemothermal oxidization,and(iii)optimizing procedures and carbon-sulfur analyzer,we have built a novel Wang-Xu-Yuan method(the WXY method)for measuring the contents of total organic carbon or black carbon in marine sediment cores,which includes the procedures of pretreatment,weighing,acidification,chemothermal oxidation and quantification;and can fully meet the requirements of establishing their highresolution temporal sequences,whatever in the recovery,experimental efficiency,accuracy and reliability of the measurements,and homogeneity of samples.In particular,the usage of disposable ceramic crucibles leads to evidently simplify the experimental scenario,which further results in the very high recovery rates for total organic carbon and black carbon.This new technique may provide a significant support for revealing the mechanism of carbon burial and evaluating the capacity of marine carbon accumulation and sequestration. 展开更多
关键词 total organic carbon black carbon marine sediment cores chemothermal oxidation disposable ceramic crucible
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Isolation and Genetic Analysis of Halophilous Bacteria from Marine Sediment Collected at Tianjin Port, China 被引量:1
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作者 ZHANG Guo-gang LIU Cheng-bao +4 位作者 JIA Mei-qing HUANG Jing XIE Li-na YIN Xue SUI Xin 《Agricultural Science & Technology》 CAS 2018年第5期50-58,共9页
[Objective] Marine sediment from Tianjin Port has a extremely high salinity.The bacteria which live in such habitats have evolved distinct physiological,metabolic,and morphological characteristics to survive.The objec... [Objective] Marine sediment from Tianjin Port has a extremely high salinity.The bacteria which live in such habitats have evolved distinct physiological,metabolic,and morphological characteristics to survive.The objective of this study is to identify all the specific salt-tolerant characteristics and the genetic evolution of the bacteria in the sediment.[Methods] In this study,the total DNA of sediment from Tianjin Port was extracted,and 16S rDNA was used to conduct an analysis of the fauna of sediment bacteria. We also isolated sediment bacteria using beef extract-peptone media with seven different NaCl concentrations (0,0.5%,2%,5%,10%,15%,and 20%),aiming to analyze the dominant species of halophilous bacteria under different salinities.[Results] 1) With each stepwise increase of salinity from 0.5% to 20%,the total number of isolated bacterial colonies decreased.14 strains of bacteria were identified and classified by the16S rDNA sequencing analysis.Of these,four could tolerate 0~2% salinity,four could tolerate 0~5% salinity,one could tolerate 0~15% salinity,and one tolerated within the full 0~20% salinity range.Further four strains were only able to tolerate within a few narrow salinity ranges.such as 5%~10%,10%~15%,10%~20% and 15%~20%;2) The quantity of bacteria strains that can be isolated from the marine sediment decreased with the increase of salinity. Also, the Shannon wiener index and species richness index of marine sediment bacteria decreased significantly from 5% salinity.However,there were no significant differences in the species evenness index;3) When the salinity was 0~10%,the dominant species was Bacillus.When the salinity was 15%, Halomonas was the dominant species.When the salinity was 20%,there were no significant differences in the proportions of these species.[Conclusion] Our results showed that some bacteria could tolerate living conditions with high salinity,and we even found a species which can tolerate a wide range of salinities (0~20%).In further study,it would be valuable to analyze these bacteria's unique physiological and biochemical functions that allow them to adapt to environments with high salinity.It can provide theories to promote the development of microbial population resources in marine sediment and the reclaimation of salinized soil by salt tolerant microorganisms. 展开更多
关键词 BACTERIA marine sediment 16S rDNA gene sequence SALTTOLERANCE Genetic classification
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Optimization of Ultrasonic Extraction and Clean-up Protocol for the Determination of Polycyclic Aromatic Hydrocarbons in Marine Sediments by High-performance Liquid Chroma-tography Coupled with Fluorescence Detection 被引量:1
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作者 PENG Xuewei YAN Guofang +3 位作者 LI Xianguo GUO Xinyun ZHOU Xiao WANG Yan 《Journal of Ocean University of China》 SCIE CAS 2012年第3期331-338,共8页
The procedures of ultrasonic extraction and clean-up were optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. Samples were ultrasonically extracted, and the extracts were pu... The procedures of ultrasonic extraction and clean-up were optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. Samples were ultrasonically extracted, and the extracts were purified with a miniaturized silica gel chromatographic column and analyzed with high performance liquid chromatography (HPLC) with a fluorescence detector. Ultrasonication with methanol-dichloromethane (2:1, v/v) mixture gave higher extraction efficiency than that with dichloromethane. Among the three elution solvents used in clean-up step, dichloromethane-hexane (2:3, v/v) mixture was the most satisfactory. Under the optimized conditions, the recoveries in the range of 54.82% to 94.70% with RSDs of 3.02% to 23.22% for a spiked blank, and in the range of 61.20% to 127.08% with RSDs of 7.61% to 26.93% for a spiked matrix, were obtained for the 15 PAHs studied, while the recoveries for a NIST standard reference SRM 1941b were in the range of 50.79% to 83.78% with RSDs of 5.24% to 21.38%. The detection limits were between 0.75 ng L-1 and 10.99 ng L-1for different PAHs. A sample from the Jiaozhou Bay area was examined to test the established methods. 展开更多
关键词 ultrasonic extraction marine sediment polycyclic aromatic hydrocarbon high performance liquid chromatography
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