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Influences of petroleum on accumulation of copper and cadmium in the polychaete Nereis diversicolor

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Journal of Environmental Sciences 2006年第1期18卷 109-114页

作者： SUN Fu-hong ZHOU Qi-xing zhang qian-ru Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China College of Environmental Sciences and Engineering Nankai University Tianjin 300071 China

Using the exposure simulation experiment, the action of petroleum affecting the accumulation of the trace metals including copper （Cu） and cadmium （Cd） in littoral polychaete Nereis diversicolor collected from the Shuangtaizi Estuary in Liaoning Province, China was examined. The results showed that there was a markedly non-linear relationship between the accumulation of Cu in worms and the experimental concentration of Cu in exposure solutions when the concentration of petroleum remained at 0, 100, and 220 μl/L, respectively. However, significantly non-linear relationship for worms exposed to Cd was observed only when the concentration of added petroleum was 0 and 220 μl/L. The accumulation of Cu in worms did not differ significantly among the three different levels of petroleum concentrations combined with various concentrations of Cu. So was the accumulation of Cd in worms （p〉0.05）. However, the addition of petroleum in exposure solutions brought about an increase in the accumulation of Cu in Nereis diversicolor, in comparison with single Cu pollution. On the other hand, when the concentration of added petroleum remained at 100 μl/L, the accumulation of Cd in worms was lower than that in worms exposed to various concentrations of only cadmium. However, the worms exposed to Cd and petroleum 220 μl/L did not show obvious and identical increase in the accumulation of Cd, compared with single Cd exposure. The accumulation of both Cu and Cd in worms did not increase significantly with the increases in concentrations of Cu or Cd in exposure solutions combined with petroleum （0, 100, and 220μl/L） under the experimental conditions. Although Nereis diversicolor is exposed to very high Cu and Cd in exposure solutions, accumulation and detoxification mechanisms are sufficient to cope with the extra metal influx in order to survive.

关键词： Nereis diversicolor copper cadmium petroleum combined pollution

Toxic effects of acetochlor and methamidophos on earthworm Eisenia fetida in phaiozem, northeast China

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Journal of Environmental Sciences 2006年第4期18卷 741-745页

作者： ZHOU Qi-xing zhang qian-ru LIANG Ji-dong Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China College of Environmental Sciences and Engineering Nankai University Tianjin 300071 China College of Energy and Power Engineering Xi＇an Jiaotong University Xi＇an 710049 China

Acetochlor and methamidophos are two important agrochemicals which are widely applied to agricultural production in northeast China. The investigation on the earthworm Eisenia fetida as an important type of soil animals exposed to single and binary-combined contamination of acetochlor and methamidophos was thus carried out. The single toxic effect test showed that the two agrochemicals had their toxicity to the earthworms living in phaiozem. Acetochlor had a stronger acute toxic effect on the earthworms than methamidophos. The mortality of the earthworms exposed to individual acetochlor and methamidophos changed with an increase in the exposure time and the exposed concentrations. The LD50 value of acetochlor and methamidophos toxic to the earthworms was 115.6-275,3 and 29.5-228.6 mg/kg, respectively. The weight of the earthworms was a more sensitive index compared to the mortality in indicating toxic effects of acetochlor and methamidophos in phaiozem. When considering both the mortality and the body-weight change, the combined pollution of acetochlor and methamidophos in phaiozem resulted in their synergic toxic effects on the earthworms.

关键词： ecological safety earthworm Eiseniafetida acetochlor methamidophos combined pollution soil ecotoxicology

Technical Innovation of Land Treatment Systems for Municipal Wastewater in Northeast China

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Pedosphere 2006年第3期16卷 297-303页

作者： ZHOU Qi-Xing zhang qian-ru SUN Tie-Heng Shenyang Key Laboratory of Environmental Engineering Shenyang University Shenyang 110010 （China） College of Environmental Science and Engineering Nankai University Tianjin 300071 （China） Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China） Graduate School of the Chinese Academy of Sciences Beijing 100039 （China）

On the basis of ecological principles including holistic optimization, cycling and regeneration, and regional differentiation, land treatment systems (LTSs) for municipal wastewater were continuously explored and updated in the western Shenyang area and the Huolinhe area, China. Intensified pretreatment, addition of a man-made soil filtration layer, and use of an ecologically diversified secondary plant cover were proved to be technically feasible. Hydraulic loading was determined according to the assimilation capacity of soil ecosystems, thus ensuring safe operation of wastewater treatment. This modernized and alternative approach to wastewater treatment had been widely applied in middle-sized and small cities and towns of Northeast China, and these innovative systems in some areas had indicated favorable ecological, social, and economic benefits.

关键词： land treatment system municipal wastewater soil ecosystem soil purification

Ecological effects of crude oil residues on the functional diversity of soil microorganisms in three weed rhizospheres

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Journal of Environmental Sciences 2006年第6期18卷 1101-1106页

作者： zhang qian-ru ZHOU Qi-xing REN Li-ping ZHU Yong-guan SUN Shu-lan Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China College of Environmental Science and Engineering Nankai University Tianjin 300071 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Kyushu University Fukuoka 8128582 Japan

Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion （Taraxacum officinale）, jerusalem artichoke （Silphiurn perfoliatum L.） and evening primrose （A colypha australis L.） rhizospheric soils were thus examined using the method of carbon source utilization. The results indicated that there were various toxic effects of crude oil residues on the growth and reproduction of soil bacteria, but the weed rhizospheres could mitigate the toxic effects. Total heterotrophic counting colony-forming units （CFUs） in the rhizospheric soils were significantly higher than those in the non-rhizospheric soils. The culturable soil-bacterial CFUs in the jerusalem artichoke （S. perfoliatum） rhizosphere polluted with 0.50 kg/pot of crude oil residues were almost twice as much as those with 0.25 kg/pot and without the addition of crude oil residues. The addition of crude oil residues increased the difference in substrate evenness, substrate richness, and substrate diversity between non-rhizospheric and rhizospheric soils of T. officinale and A. australis, but there was no significant （p〉0.05） difference in the Shannon＇s diversity index between non-rhizospheric and rhizospheric soils of S. perfoliatum. The rhizospheric response of weed species to crude oil residues suggested that S. perfoliatum may be a potential weed species for the effective plant-microorganism bioremediation of contaminated soils by crude oil residues.

关键词： ecological effect weed rhizosphere crude oil residue soil microorganism functional diversity

两种贻贝对麻痹性贝类毒素蓄积代谢及生理应激的比较研究

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海洋与湖沼 2024年第5期55卷 1183-1190页

作者：杨越聪张倩茹郑关超赵辉辉王潇潇谭志军吴海燕农业农村部水产品质量安全检测与评价重点实验室中国水产科学研究院黄海水产研究所山东青岛266071 上海海洋大学食品学院上海201306 海水养殖生物育种与可持续产出全国重点实验室中国水产科学研究院黄海水产研究所山东青岛266071

贻贝是我国沿海常见的经济贝类,作为监测海洋污染情况的前哨物种对多种贝类毒素均具有较强的蓄积能力,但不同贻贝蓄积能力的种间差异尚不清晰。基于贝类软组织质量比原则,将紫贻贝与厚壳贻贝分别暴露于链状亚历山大藻,研究两种贻贝对麻... 详细信息

贻贝是我国沿海常见的经济贝类,作为监测海洋污染情况的前哨物种对多种贝类毒素均具有较强的蓄积能力,但不同贻贝蓄积能力的种间差异尚不清晰。基于贝类软组织质量比原则,将紫贻贝与厚壳贻贝分别暴露于链状亚历山大藻,研究两种贻贝对麻痹性贝类毒素(paralytic shellfish toxins,PSTs)的蓄积代谢与生理应激差异。结果表明,紫贻贝和厚壳贻贝中PSTs最高蓄积量分别为889.1和358.6μg STXeq/kg,前者超出后者的2倍。代谢3天后,厚壳贻贝PSTs的清除率为88.8%,而紫贻贝仅为42.5%。皮尔逊相关性分析表明,两种贻贝各组织单日PSTs蓄积量与其产毒藻吸收率呈显著正相关(P0.05)。在生理应激方面,紫贻贝对产毒藻的清滤率与吸收率为厚壳贻贝的两倍。此外,紫贻贝肝胰腺组织的氧化应激与组织损伤更严重,导致其肝胰腺中PSTs向其他组织转移量与清除率均显著低于厚壳贻贝(P<0.05)。综上所述,产毒藻暴露下厚壳贻贝通过改变摄食行为降低PSTs的蓄积量,导致厚壳贻贝中PSTs的安全风险明显低于紫贻贝,研究结果为探究不同双壳贝类对PSTs的蓄积差异机理提供了思路。

关键词：贻贝种间差异蓄积代谢摄食行为生理应激

Blast damage zone strength reduction method for deep cavern excavation and its application

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 236-251页

作者： Tianzhi YAO Zuguo MO Li qian Yunpeng GAO Jianhai zhang Xianglin XING Enlong LIU ru zhang State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu 610065China Power China Chengdu Engineering Corporation Limited Chengdu 610072China

The drill and blast(D&B)method is widely used to excavate underground spaces,but explosions generally cause damage to the ***,no blast simulation method can provide computational accuracy and *** this paper,a blast equivalent simulation method called the blast damage zone strength reduction(BDZSR)method is *** method first calculates the range of the blast-induced damage zone(BDZ)by formulae,then reduces the strength and deformation parameters of the rock within the BDZ ahead of excavation,and finally calculates the excavation damage zone(EDZ)for the D&B method by numerical *** method combines stress wave attenuation,rock damage criteria and stress path variation to derive the BDZ depth calculation *** formulae consider the initial geo-stress,and the reliability is verified by numerical *** calculation of BDZ depth with these formulae allows the corresponding numerical simulation to avoid the time-consuming dynamic calculation process,thus greatly enhancing the calculation *** method was applied to the excavation in Jinping Class II hydropower station to verify its *** results show that the BDZSR method can be applied to blast simulation of underground caverns and provide a new way to study blast-induced damage.

关键词： attenuation of stress wave deep-buried underground building drill and blast in situ stress

A macro-mesoscopic constitutive model for porous and cracked rock under true triaxial conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3080-3098页

作者： Li qian Zuguo Mo Jianhai zhang Xianglin Xing ru zhang Tianzhi Yao Yunpeng Gao State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu610065China Power China Chengdu Engineering Corporation Limited Chengdu610072China

The complex mechanical and damage mechanisms of rocks are intricately tied to their diverse mineral compositions and the formation of pores and cracks under external *** rock tests reveal a complex interplay between the closure of porous defects and the propagation of induced cracks,presenting challenges in accurately representing their mechanical properties,especially under true triaxial stress *** paper proposes a conceptualization of rock at the mesoscopic level as a two-phase composite,consisting of a bonded medium matrix and frictional medium *** bonded medium is characterized as a mesoscopic elastic material,encompassing various minerals surrounding porous *** mechanical properties are determined using the mixed multi-inclusion *** of the bonded medium into the frictional medium occurs through crack extension,with its elastoplastic properties defined by the DruckerePrager yield criterion,accounting for hardening,softening,and *** and Eshelby’s equivalent inclusion methods are applied to the bonded and frictional media,*** macroscopic mechanical properties of the rock are derived from these mesoscopic ***,a True Triaxial Macro-Mesoscopic(TTMM)constitutive model is *** model effectively captures the competitive effect and accurately describes the stress-deformation characteristics of *** the TTMM model,the strains resulting from porous defect closure and induced crack extension are differentiated,enabling quantitative determination of the associated damage evolution.

关键词： Micromechanics Macroemesoscopic Homogenization Constitutive model Competitive effect

Sequential good lattice point sets for computer experiments

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Science China Mathematics 2024年第9期67卷 2153-2170页

作者： Xue-ru zhang Yong-Dao Zhou Min-qian Liu Dennis K.J.Lin NITFID LPMC&KLMDASRSchool of Statistics and Data ScienceNankai UniversityTianjin 300071China Department of Statistics Purdue UniversityWest LafayetteIN 47907USA

Sequential Latin hypercube designs(SLHDs) have recently received great attention for computer experiments, with much of the research restricted to invariant spaces. The related systematic construction methods are inflexible, and algorithmic methods are ineffective for large designs. For designs in contracting spaces, systematic construction methods have not been investigated yet. This paper proposes a new method for constructing SLHDs via good lattice point sets in various experimental spaces. These designs are called sequential good lattice point(SGLP) sets. Moreover, we provide efficient approaches for identifying the(nearly)optimal SGLP sets under a given criterion. Combining the linear level permutation technique, we obtain a class of asymptotically optimal SLHDs in invariant spaces, where the L1-distance in each stage is either optimal or asymptotically optimal. Numerical results demonstrate that the SGLP set has a better space-filling property than the existing SLHDs in invariant spaces. It is also shown that SGLP sets have less computational complexity and more adaptability.

关键词： contracting space maximin distance nested Latin hypercube design sequential design space-fillingdesign

BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： Yu zhang Bei Gong qian Wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication