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A 50-year sedimentary record of heavy metals and their chemical speciations in the Shuangtaizi River estuary (China): implications for pollution and biodegradation

Baolin LIU, Ke HU, Zhenglong JIANG, Fengge QU, Xin SU

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 435-444 doi: 10.1007/s11783-011-0352-0

摘要: Two parallel sediment cores collected from tidal flat located in the Shuangtaizi River estuary were analyzed for heavy metal concentrations and chemical speciations. Based on the Cs activity profile, mean sedimentation rate at the sampling site during the past 50 years was estimated to be 1.3 cm·a . Correlation analyses show that almost all the metals are associated with each other, suggesting that these metals might be derived from same sources and/or affected by same geochemical processes. Influence of total organic carbon (TOC) content on the concentrations of Cr, Ni, Cu and Cd is evident. Silt and clay contents, instead of sand content, play an important role in the distribution of these metals. The dominant binding phases for most of the metals (except for Cd) are the residual. The relative decrease of the residual fraction of Cd and Pb in the upper 66 cm of the core is striking. The distribution of chemical fraction confirms that the residual fractions of these metals have a natural origin, while only the non-residual fractions of Cd and Pb increased upward the core due to pollution in the past five decades. Pollution assessment on these heavy metals based on Index of Geoaccumulation ( ) also demonstrates that most of the metals are unpolluted. The weak pollution as observed in the sediments is perhaps related to a local plant, the Kitag, which may have played a significant role in the biodegradation of these metals and the metal distribution in the estuary.

关键词: Shuangtaizi River estuary     sediment core     heavy metals     pollution    

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1427-1

摘要:

• Sediment desiccation alters morphological characteristics of aquatic sediment.

关键词: Fibrous-root macrophytes     Thick-root macrophytes     Nutrients removal     Wet sediment     Dried-rewetted sediment    

Diversity and vertical distributions of sediment bacteria in an urban river contaminated by nutrients

Xunan YANG, Shan HUANG, Qunhe WU, Renduo ZHANG, Guangli LIU

《环境科学与工程前沿(英文)》 2013年 第7卷 第6期   页码 851-859 doi: 10.1007/s11783-013-0569-1

摘要: The aim of this study was to investigate the benthic bacterial communities in different depths of an urban river sediment accumulated with high concentrations of nutrients and metals. Vertical distributions of bacterial operational taxonomic units (OTUs) and chemical parameters (nutrients: , , dissolved organic carbon, and acid volatile sulfur; metals: Fe, Zn, and Cu) were characterized in 30 cm sediment cores. The bacterial OTUs were measured using the terminal restriction fragment length polymorphism analysis. Biodiversity indexes and multivariate statistical analyses were used to characterize the spatial distributions of microbial diversity in response to the environmental parameters. Results showed that concentrations of the nutrients and metals in this river sediment were higher than those in similar studies. Furthermore, high microbial richness and diversity appeared in the sediment. The diversity did not vary obviously in the whole sediment profile. The change of the diversity indexes and the affiliations of the OTUs showed that the top layer had different bacterial community structure from deeper layers due to the hydrological disturbance and redox change in the surface sediment. The dominant bacterial OTUs ubiquitously existed in the deeper sediment layers (5–27 cm) corresponding to the distributions of the nutrients and metals. With much higher diversity than the dominant OTUs, the minor bacterial assemblages varied with depths, which might be affected by the sedimentation process and the environmental competition pressure.

关键词: heavy metals     nutrients     sediment profile     terminal restriction fragment length polymorphism    

Microbial responses to the use of NaClO in sediment treatment

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1451-1

摘要:

• Chlorine addition enhanced the release of TOC, TN from the sediment.

关键词: Sediment chlorination     Substance mobility     Microbial response     Community composition     Function    

黄土高原生态重建的水沙效应研究 Article

孙彭成, 吴一平, 杨志峰, Bellie Sivakumar, 邱临静, 刘曙光, 蔡宴朋

《工程(英文)》 2019年 第5卷 第5期   页码 855-864 doi: 10.1016/j.eng.2019.07.014

摘要:

黄土高原是全球土壤侵蚀最为严重的区域之一,也是黄河泥沙的主要来源。自20世纪50年代大规模水土保持措施实施以来,该地区入黄泥沙量持续减少,流域内泥沙来源与输移机制变得更为复杂,对水土保持措施作用下的河流输沙及变异特征的研究一直是学界关注的重点。本文以水土保持治理成效最为显著的黄土丘陵沟壑区的典型区域为研究对象,采用近50年的水沙观测数据,分析水土保持作用下流域水沙关系演变。结果表明,水土保持措施的实施引发流域水沙关系的显著变化,具体表现为幂指数水沙关系中系数的减小和指数的增加,且前阶段指数增加缓慢而后期增加剧烈。幂指数的增加表征新的更加陡峭的水沙关系曲线,意味着流域年际输沙变异程度或将增强。此外,新旧水沙关系曲线存在一个临界交点,在新的水沙关系条件下,低于临界流量的径流将输移更少的泥沙,这也是该地区泥沙输移新的主导状态;然而,大于临界流量的极端径流也有可能引发更强的泥沙输移。因此,本文认为黄土高原的低泥沙输移未必是一种新常态,极端洪水条件下仍有强输沙的可能性而需增强防范。

关键词: 流域水沙关系     生态恢复     黄土丘陵沟壑区     泥沙输移     水沙关系参数    

Red soil for sediment capping to control the internal nutrient release under flow conditions

Lei Xia, Guo Liu, Chunmei Chen, Meiyan Wen, Yangyang Gao

《环境科学与工程前沿(英文)》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0886-2

摘要: The inhibition of sediment nitrogen (N) and phosphorus (P) release seems necessary. Red soil (RS) was firstly used as sediment capping material under flow conditions. RS capping can effectively reduce the N and P release from sediment. Nitrogen (N) and phosphorus (P) released from the sediment to the surface water is a major source of water quality impairment. Therefore, inhibiting sediment nutrient release seems necessary. In this study, red soil (RS) was employed to control the nutrients released from a black-odorous river sediment under flow conditions. The N and P that were released were effectively controlled by RS capping. Continuous-flow incubations showed that the reduction efficiencies of total N (TN), ammonium (NH -N), total P (TP) and soluble reactive P (SRP) of the overlying water by RS capping were 77%, 63%, 77% and 92%, respectively, and nitrification and denitrification occurred concurrently in the RS system. An increase in the water velocity coincided with a decrease in the nutrient release rate as a result of intensive water aeration.

关键词: Sediment     Red soil capping     Flow conditions     Nitrogen     Phosphorus    

Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

《环境科学与工程前沿(英文)》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1463-x

摘要:

• Lanthanum modified bentonite (LMB) can effectively absorb phosphorus (P).

关键词: Sediment     Eutrophication     Thin-layer capping     Phosphorus     Nitrogen     Aluminum-based P-inactivation agent    

Postprocessor development for ultrasonic cutting of honeycomb core curved surface with a straight blade

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0729-8

摘要: When ultrasonically cutting honeycomb core curved parts, the tool face of the straight blade must be along the curved surface’s tangent direction at all times to ensure high-quality machining of the curved surface. However, given that the straight blade is a nonstandard tool, the existing computer-aided manufacturing technology cannot directly realize the above action requirement. To solve this problem, this paper proposed an algorithm for extracting a straight blade real-time tool face vector from a 5-axis milling automatically programmed tool location file, which can realize the tool location point and tool axis vector conversion from the flat end mill to the straight blade. At the same time, for the multi-solution problem of the rotation axis, the dependent axis rotation minimization algorithm was introduced, and the spindle rotation algorithm was proposed for the tool edge orientation problem when the straight blade is used to machine the curved part. Finally, on the basis of the MATLAB platform, the dependent axis rotation minimization algorithm and spindle rotation algorithm were integrated and compiled, and the straight blade ultrasonic cutting honeycomb core postprocessor was then developed. The model of the machine tool and the definition of the straight blade were conducted in the VERICUT simulation software, and the simulation machining of the equivalent entity of the honeycomb core can then be realized. The correctness of the numerical control program generated by the postprocessor was verified by machining and accuracy testing of the two designed features. Observation and analysis of the simulation and experiment indicate that the tool pose is the same under each working condition, and the workpieces obtained by machining also meet the corresponding accuracy requirements. Therefore, the postprocessor developed in this paper can be well adapted to the honeycomb core ultrasonic cutting machine tool and realize high-quality and high-efficient machining of honeycomb core composites.

关键词: honeycomb core     straight blade     ultrasonic cutting     tool pose     postprocessor    

Characterization of interaction between different adsorbents and copper by simulation experiments using sediment-extracted

Yan ZHANG,Yuan ZHANG,Tao YU

《环境科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 510-518 doi: 10.1007/s11783-013-0588-y

摘要: The complex capacity of different types of organic matters (OMs) for Cu was quantitatively studied by simulation experiments using different adsorbents prepared from the sediment in Taihu Lake. The free Cu was measured with ion selective electrode (ISE) and complex capacity was calculated using a conditional formation constant model. The result indicated that the complex capacity was 0.048 mmol·g , 0.009 and 0.005 mmol·g for raw sediment, sediment without DOM, sediment without insoluble organic matters but with DOM and sediment without OM. Insoluble organic matter played a major role in the sorption of Cu in sediment and it can adsorb most Cu from water column. In the solution, Cu mainly existed as a complex with DOM and the DOM-Cu complexation capacity was 327.87 mg·g . The change of TOC and pH indicated ion-exchange in the interaction between free Cu and DOM. When the Cu concentration in the experiment reached the complex capacity of DOM, precipitation was the major mechanism to remove Cu from water phase, which was observed from UV absorbance change of DOM, that is, its aromaticity increased while molecular weight decreased. The desorption result indicated that DOM was more capable of desorbing Cu from adsorbents without OM than adsorbent with OM. The desorbed quantity with DOM was 1.65, 1.78 and 2.25 times higher than that with water for adsorbents without OM, raw adsorbents (sediment) and adsorbents without DOM.

关键词: interaction     dissolved organic matters     sediment     sorption     desorption     Taihu Lake    

Effects of different sediment fractions on sorption of galaxolide

Lixia JIN, Mengchang HE, Jinghuan ZHANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 59-65 doi: 10.1007/s11783-010-0259-1

摘要: Sorption isotherms of galaxolide (HHCB) of different fractions from two sediments with different mineral and organic carbon contents were determined to compare HHCB sorption behavior and contribution to the total sorption. The HHCB sorption isotherms that used the batch equilibration method were studied on different sediments of different fractions. The sorption isotherms of 600°C heating fractions were detailed using the linear model, while the other fractions were nonlinear and fitted well with the Freundlich model. The dissolved organic carbon (DOC) removed, NaOH extracted, and 375°C heating fractions showed more nonlinear sorption than the original sediments, which suggested more heterogeneous sorption sites in these fractions. Compared to the original sediments, the 375°C heating fractions had higher carbon-normalized distribution coefficient ( ) values, indicating a higher sorption affinity for HHCB. Among the different sediment fractions, the contribution of the 600°C heating fractions to the overall sorption were the lowest (<20%), while the 375°C heating fractions were the highest (up to 85%).

关键词: galaxolide (HHCB)     sorption     organic carbon     sediment     carbon-normalized distribution coefficient (Koc)    

新形势下黄河水沙调控策略研究

胡春宏,张双虎,张晓明

《中国工程科学》 2022年 第24卷 第1期   页码 122-130 doi: 10.15302/J-SSCAE-2022.01.013

摘要:

黄河水沙调控对保障黄河长久安澜至关重要。近几十年来,受自然因素和水土保持等人类活动的双重影响,黄河来水来沙量持续发生变化,水资源量略有减少、来沙量锐减,为此,科学研判未来黄河来水来沙量是制定水沙调控策略最基础、最关键的科学问题。本文分析了1919—2020 年百年尺度下的黄河来水来沙量的演变情况,并预测了未来50 年的黄河来水来沙量;系统总结了目前黄河水沙调控面临的主要问题,即黄河上游河道淤积萎缩、黄河下游滩区治理策略与高质量发展要求不适应、黄土高原水土流失治理区域不均衡等。在此基础上,提出了新水沙条件下的黄河水沙调控策略建议,一是以黄河上游黑山峡河段开发和古贤水利枢纽建设为重点,完善水沙调控体系;二是黄河下游滩区分区治理、改造河道并释放部分滩区,实现滩区防洪运用与高质量发展的协同;三是科学开展黄土高原分区分类水土保持措施,调整黄土高原治理格局,协同推进生态保护和乡村振兴。

关键词: 黄河     新水沙条件     水沙调控     水利枢纽     分区治理     生态保护    

Rapid control of black and odorous substances from heavily-polluted sediment by oxidation: Efficiency

Kun Li, Min Yang, Jianfeng Peng, Ruiping Liu, Tista Prasai Joshi, Yaohui Bai, Huijuan Liu

《环境科学与工程前沿(英文)》 2019年 第13卷 第6期 doi: 10.1007/s11783-019-1171-y

摘要: Oxidants were proposed to rapidly control black and odorous substances in sediments. NaClO and KMnO4 had excellent efficiency to remove black and odorous substances. NaClO dramatically accelerated the release of organics, NH4+-N, P, and heavy-metals. Moderate oxidation had a limited effect on microbial communities. NaClO of 0.2 mmol/g was viewed to be the optimum option. The control of black and odorous substances in sediments is of crucial importance to improve the urban ecological landscape and to restore water environments accordingly. In this study, chemical oxidation by the oxidants NaClO, H2O2, and KMnO4 was proposed to achieve rapid control of black and odorous substances in heavily-polluted sediments. Results indicate that NaClO and KMnO4 are effective at removing Fe(II) and acid volatile sulfides. The removal efficiencies of Fe(II) and AVS were determined to be 45.2%, 94.1%, and 93.7%, 89.5% after 24-h exposure to NaClO and KMnO4 at 0.2 mmol/g, respectively. Additionally, rapid oxidation might accelerate the release of pollutants from sediment. The release of organic matters and phosphorus with the maximum ratios of 22.1% and 51.2% was observed upon NaClO oxidation at 0.4 mmol/g. Moreover, the introduction of oxidants contributed to changes in the microbial community composition in sediment. After oxidation by NaClO and KMnO4 at 0.4 mmol/g, the Shannon index decreased from 6.72 to 5.19 and 4.95, whereas the OTU numbers decreased from 2904 to 1677 and 1553, respectively. Comparatively, H2O2 showed a lower effect on the removal of black and odorous substances, pollutant release, and changes in sediment microorganisms. This study illustrates the effects of oxidant addition on the characteristics of heavily polluted sediments and shows that chemical oxidants may be an option to achieve rapid control of black and odorous substances prior to remediation of water environments.

关键词: Oxidants     Heavily polluted sediment     Black and odorous substances     Release behaviors     Microorganism    

辽河流域水环境沉积物质量风险评估

秦延文,韩超南,郑丙辉,张雷,曹伟

《中国工程科学》 2013年 第15卷 第3期   页码 19-25

摘要:

采集辽河流域浑河、太子河干流及大伙房水库共56个站点的表层沉积物样品,根据相平衡分配法的修正模型建立辽河流域沉积物重金属质量基准(Cu、Pb、Zn、Cd的SQC(基于CCC)分别为75.26 μg/g、25.72 μg/g、255.96 μg/g、2.52 μg/g),依据重金属急、慢性生物毒性风险确定辽河流域沉积物重金属质量三级标准,并创建沉积物质量风险评估方法——沉积物污染指数法(SPI),对辽河流域水环境进行沉积物质量风险评估,评估结果显示:浑河干流中下游、太子河中上游及大伙房水库库中、库尾处的沉积物质量状况为中风险,此沉积物重金属污染状况使长期生活在其中的底栖生物受到轻微重金属慢性毒性影响,其中浑河中游红透山铜矿处和细河上游沈阳工业区的沉积物质量风险极高。

关键词: 沉积物质量风险评估     沉积物质量基准     沉积物质量标准     沉积物污染指数法     重金属    

integrated method for the rapid dewatering and solidification/stabilization of dredged contaminated sediment

Hefu Pu, Aamir Khan Mastoi, Xunlong Chen, Dingbao Song, Jinwei Qiu, Peng Yang

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1359-1

摘要: Abstract • An integrated method, called PHDVPSS, was proposed for treating DCS. • The PHDVPSS method showed superior performance compared to conventional method. • Using the method, water content (%) of DCS decreased from 300 to<150 in 3 days. • The 56-day UCS from this method is 12‒17 times higher than conventional method. • Relative to PC, GGBS-MgO binder yielded greater reduction in the leachability. To more efficiently treat the dredged contaminated sediment (DCS) with a high water content, this study proposes an integrated method (called PHDVPSS) that uses the solidifying/stabilizing (S/S) agents and prefabricated horizontal drain (PHD) assisted by vacuum pressure (VP). Using this method, dewatering and solidification/stabilization can be carried out simultaneously such that the treatment time can be significantly shortened and the treatment efficacy can be significantly improved. A series of model tests was conducted to investigate the effectiveness of the proposed method. Experimental results indicated that the proposed PHDVPSS method showed superior performance compared to the conventional S/S method that uses Portland cement (PC) directly without prior dewatering. The 56-day unconfined compressive strength of DCS treated by the proposed method with GGBS-MgO as the binder is 12‒17 times higher than that by the conventional S/S method. DCS treated by the PHDVPSS method exhibited continuous decrease in leaching concentration of Zn with increasing curing age. The reduction of Zn leachability is more obvious when using GGBS-MgO as the binder than when using PC, because GGBS-MgO increased the residual fraction and decreased the acid soluble fraction of Zn. The microstructure analysis reveals the formation of hydrotalcite in GGBS-MgO binder, which resulted in higher mechanical strength and higher Zn stabilization efficiency.

关键词: Dredged contaminated sediment     Dewatering     Solidification/stabilization     Vacuum preloading     Prefabricated horizontal drain     Heavy metal    

Establishment and verification of a shrinking core model for dilute acid hydrolysis of lignocellulose

Cunwen WANG, Xiaoling DUAN, Weiguo WANG, Zihao LI, Yuanhang QIN

《能源前沿(英文)》 2012年 第6卷 第4期   页码 413-419 doi: 10.1007/s11708-012-0212-z

摘要: The kinetics of lignocellulose hydrolysis under the conditions of high temperature and dilute acid (mass fraction 0.05%) was investigated in this paper. By studying the reducing sugar concentration versus reaction temperature (170°C–220°C) and reaction time (150–1800 s) during the hydrolysis process of five kinds of crop straw (rice, wheat, cotton, rape and corn), the shrinking core model was established, and the differential equation of the model and its analytical solution were obtained. With a numerical calculation method, the kinetic equation was estimated, and the degradation of reducing sugar obeyed first-order kinetics was obtained. The calculated results from the equations agreed well with the original experimental data. The calculation by the model showed that the reducing sugar concentration increases as the size of the particles decrease, and the uniform particles increase.

关键词: lignocellulose     dilute acid hydrolysis     shrinking core model    

标题 作者 时间 类型 操作

A 50-year sedimentary record of heavy metals and their chemical speciations in the Shuangtaizi River estuary (China): implications for pollution and biodegradation

Baolin LIU, Ke HU, Zhenglong JIANG, Fengge QU, Xin SU

期刊论文

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

期刊论文

Diversity and vertical distributions of sediment bacteria in an urban river contaminated by nutrients

Xunan YANG, Shan HUANG, Qunhe WU, Renduo ZHANG, Guangli LIU

期刊论文

Microbial responses to the use of NaClO in sediment treatment

期刊论文

黄土高原生态重建的水沙效应研究

孙彭成, 吴一平, 杨志峰, Bellie Sivakumar, 邱临静, 刘曙光, 蔡宴朋

期刊论文

Red soil for sediment capping to control the internal nutrient release under flow conditions

Lei Xia, Guo Liu, Chunmei Chen, Meiyan Wen, Yangyang Gao

期刊论文

Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

期刊论文

Postprocessor development for ultrasonic cutting of honeycomb core curved surface with a straight blade

期刊论文

Characterization of interaction between different adsorbents and copper by simulation experiments using sediment-extracted

Yan ZHANG,Yuan ZHANG,Tao YU

期刊论文

Effects of different sediment fractions on sorption of galaxolide

Lixia JIN, Mengchang HE, Jinghuan ZHANG

期刊论文

新形势下黄河水沙调控策略研究

胡春宏,张双虎,张晓明

期刊论文

Rapid control of black and odorous substances from heavily-polluted sediment by oxidation: Efficiency

Kun Li, Min Yang, Jianfeng Peng, Ruiping Liu, Tista Prasai Joshi, Yaohui Bai, Huijuan Liu

期刊论文

辽河流域水环境沉积物质量风险评估

秦延文,韩超南,郑丙辉,张雷,曹伟

期刊论文

integrated method for the rapid dewatering and solidification/stabilization of dredged contaminated sediment

Hefu Pu, Aamir Khan Mastoi, Xunlong Chen, Dingbao Song, Jinwei Qiu, Peng Yang

期刊论文

Establishment and verification of a shrinking core model for dilute acid hydrolysis of lignocellulose

Cunwen WANG, Xiaoling DUAN, Weiguo WANG, Zihao LI, Yuanhang QIN

期刊论文