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Journal of Environmental Sciences 2006年第3期18卷 519-524页

作者： ZHAO bing LIU zheng-tao XU Zhang-fa China Research Academy of Environmental Sciences Beijing 100012 China Department of Environmental Science and Technology East China Normal University Shanghai 200061 China

Both pentachlorophenol and 2,3,7,8-tetrachlorodibenzo-p-dioxin （TCDD） had been studied widely because of their probable anti-estrogenic activity. Sodium pentachlorophenol （PCP-Na）, as a industrial product used in many fields, usually contains a trace of TCDD. The aim of this study was to assess the anti-estrogenic effect of PCP-Na in juvenile goldfish （Gurassius auratus） hepatocyte cultures using vitellogenin （VTG） as the biomarker. The ID50 of PCP-Na was investigated and then a series of concentrations （0.001 0.5 μg/ml） of PCP-Na were evaluated to estimate the anti-estrogenic activity. Results showed that PCP-Na was cytotoxic for hepatocytes even at very low concentration 〈1.21 μg/ml, and it could not induce VTG at any concentrations tested. Since it failed to stimulate VTG production, the possibility of its anti-estrogenic effect was tested, and a well-known anti-estrogenic compound-tamoxifen was used as positive control. PCP-Na caused a reduction in VTG synthesis in juvenile goldfish （Carassius auratus） hepatocytes at concentrations 〉0.1μg/ml when co-exposure with 1μg/ml 17β-estradiol （E2）, making its anti-estrogenic activity approximately as potent as tamoxifen. Our results indicate that PCP-Na can act as negative modulators of estrogenic function in juvenile goldfish （Carassius auratus） hepatocytes.

关键词： PCP-Na vitellogenin juvenile goldfish hepatocytes anti-estrogenic activity

FLOWS THROUGH ENERGY DISSIPATERS WITH SUDDEN REDUCTION AND SUDDEN ENLARGEMENT FORMS

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Journal of Hydrodynamics 2010年第3期22卷 360-365页

作者： WU Jian-hua ai Wan-zheng College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The energy dissipation of flood discharges has been one of important problems that affect directly the safety of hydropower projects. The energy dissipater with sudden reduction and sudden enlargement forms, used widely in large-scale projects has been a kind of effective structure for energy dissipation. The concept of critical thickness was defined, which is related to both the geometric parameters and the hydraulic parameters of the energy dissipater, and the factors affecting the critical thickness, were analzsed by means of dimensional analysis. The empirical expression about the critical thickness was obtained and could be used as the criterion to distinguish the flows through the energy dissipater, i.e., the plug flow and the orifice plate flow. The error analysis showed that the critical thickness calculated by the expression has the errors of smaller than 10% in the estimation of the flows for the energy dissipater mentioned above.

关键词： critical thickness energy dissipater orifice plate plug reduction ratio sudden reduction sudden enlargement

Assessment of future Antarctic amplification of surface temperature change under different Scenarios from CMIP6

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Journal of Mountain Science 2023年第4期20卷 1074-1089页

作者： ZHU Jiang-ping XIE ai-hong QIN Xiang XU bing State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China Weather Modification Office of Liaoning Province Shenyang110000China

Global warming may result in increased polar amplification,but future temperature changes under different climate change scenarios have not been systematically investigated over *** index of Antarctic amplification(AnA)is defined,and the annual and seasonal variations of Antarctic mean temperature are examined from projections of the Coupled Model Intercomparison Project Phase 6(CMIP6)under scenarios SSP119,SSP126,SSP245,SSP370 and *** occurs under all scenarios,and is strongest in the austral summer and autumn,with an AnA index greater than *** the warming over Antarctica accelerates with increased anthropogenic forcing,the magnitude of AnA is greatest in SSP126 instead of in SSP585,which may be affected by strong ocean heat uptake in high forcing ***,future AnA shows seasonal difference and regional *** is most conspicuous in the East Antarctic sector,with the amplification occurring under all scenarios and in all seasons,especially in austral summer when the AnA index is greater than 1.50,and the weakest signal appears in austral ***,the AnA over West Antarctica is strongest in austral *** SSP585,the temperature increase over the Antarctic Peninsula exceeds 0.5℃when the global average warming increases from 1.5℃to 2.0℃above preindustrial levels,except in the austral summer,and the AnA index in this region is strong in the austral autumn and *** projections suggest that the warming rate under different scenarios might make a large difference to the future AnA.

关键词： Antarctic Amplification Amplification index CMIP6 ScenarioMIP Near-surface temperature Climate change

A Mooring System Deployment Design Methodology for Vessels at Varying Water Depths

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China Ocean Engineering 2020年第2期34卷 185-197页

作者： XU Sheng-wen LIANG Ming-xiao WANG Xue-feng DING ai-bing State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In this paper,a methodology for designing mooring system deployment for vessels at varying water depths is *** Non-dominated Sorting Genetic Algorithm-II(NSGA-II)is combined with a self-dependently developed vessel-mooring coupled program to find the optimal mooring system deployment considering both station-keeping requirements and the safety of the mooring *** case studies are presented to demonstrate the methodology by designing the mooring system deployments for a very large floating structure(VLFS)module and a semi-submersible platform respectively at three different water *** can be concluded from the obtained results that the mooring system can achieve a better station-keeping ability with relatively shorter mooring line when deployed in the shallow *** safety factor of mooring line is mainly dominated by the maximum instantaneous tension increment in the shallow water,while the pre-tension has a decisive influence on the safety factor of the mooring line in the deep water.

关键词： mooring system deployment design methodology NSGA-II varying water depths

Observation of pseudogap in SnSe2 atomic layers grown on graphite

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Frontiers of physics 2020年第4期15卷 113-120页

作者： Ya-Hui Mao Huan Shan Jin-Rong Wu Ze-Jun Li Chang-zheng Wu Xiao-Fang Zhai ai-Di Zhao bing Wang Hefei National Laboratory for Physical Sciences at the Microscale and Symergetic Innovation Center of Quantum Inforrnation and Quantum Physics University of Science and Technology of ChinaHefei 290026China School of Physical Science and Techrnology ShanghaiTech UniversityShanghai 201210China

Superconducting metal dichalcogenides(MDCs)present several similarities to the other layered SI1-perconductors like *** superconductivity in atomically thin MDCs has been demonstrated by recent experiments,however,the investigation of the superconductivity intertwined with other or-ders are *** the pseudogap in atomic layers of MDCs may help to understand the superconducting mechanism for these true two dimensional(2D)superconducting *** we report a pseudogap opening in the tunneling spectra of thin layers of SnSe2 epitaxially grown on highly oriented pyrolytic graphite(HOPG)with scanning tunneling microscopy/spectroscopy(STM/STS).A significant V-shaped pseudogap was observed to open near the Fermi level(Er)in the *** at elevated temperatures,the gap gradually evolves to a shallow *** experimental observations provide direct evidence of a pseudogap state in the electron-doped SnSe2 atomic layers on the HOPG surface,which may stimulate further exploration of the mechanism of superconductivity at 2D limit in MDCs.

关键词： scanning tunneling microscopy pseudogap metal dichalcogenides SnSe2 van der Waals epitaxy

Full frequency-phase synchronization for physical-layer distributed clocks

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 68-73,113页

作者： GUO Wei zheng Lin QIU Hong-bing School of Information and Communication Guilin University of Electronic TechnologyGuilin 541004China

In wireless networks, the majority of cooperative communications rely on the high-accuracy timing synchronization among isolated nodes. However, most presented physical-layer distributed synchronization algorithms so far cannot satisfy the requirement for real applications. To realize frequency and phase synchronization of distributed clocks, i.e., full synchronization, inspired by the character of the proportional plus integral controller that it may help an unstable system be a no steady-state error one, a new loop structure of distributed discrete phase-locked loop （PLL） is designed. Furthermore, by using algebraic graph theory, the convergence of this scheme is analyzed for both directed and undirected networks, and full synchronization is proved to be reached. Simulation results are given to corroborate the proposed algorithm and analysis.

关键词： cooperative communication wireless network distributed synchronization phase-locked loop

Downstream Channel Evolution and Its Causes in the Yuan River during the Qing Dynasty

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Journal of Earth Science 2023年第4期34卷 1263-1271页

作者： Dandan zheng Yuhui Gui Jian Kuang He bing School of Arts and Communication China University of GeosciencesWuhan 430074China School of Geography and Information Engineering China University of GeosciencesWuhan 430078China School of Urban Design Wuhan UniversityWuhan 430072China

The determination of channel evolutions and the causes is important for reconstructing the evolutionary history of river *** study aimed to elucidate the downstream channel evolution of the Yuan River in Hunan Province,China,during the Qing Dynasty via Landsat 8 satellite image data and relevant *** objective was to establish the modes of channel evolution and discuss the significance of historical climate *** downstream paleochannel of the Yuan River was identified in the Late Ming Dynasty and Early Qing Dynasty(1600–1644 AD),the Kangxi-Qianlong periods of the Qing Dynasty(1661–1796 AD),the Late Qing Dynasty(1840–1912 AD),and the World War II(1939–1945 AD),and three main modes of river evolution were *** remote sensing data and the ancient literature,the evolution characteristics of the paleochannel in the Lower Yuan River were analyzed and its distribution across historical periods was comprehensively *** findings reveal a strong correlation between channel evolution,flood events,and climate *** flood events that occurred from the Late Qing Dynasty to the World War II caused a high rate of channel evolution,demonstrating the combined effects of climate change and human *** findings will help adopt robust and resilient hydrological management methods in the future of a changing climate.

关键词： Qing Dynasty downstream of Yuan River river evolution river evolution causes cli-mate change climate change channel evolution.

Feasible strategy for the nitrogen fixation and humification quality improvement by spent mushroom substrate as conditioning agent

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 235-240页

作者： Shuang ai Yuanbei Zhang Guoxiang zheng College of Engineering Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Swine Facilities Engineering Ministry of Agriculture and Rural AffairsHarbin 50030China Heilongjiang Key Laboratory of Technology and Equipment for the Utilization of Agricultural Renewable Resources Harbin 150030China

There is an overlooked problem which increasing microbial abundance while reducing nitrogen loss during *** study investigated the viability of spent mushroom substrate(SMS)as conditioners in the aerobic composting of kitchen waste(KW)with cattle manure(CM).The variation of temperature,pH,C/N,organic matter,cellulose,hemicelluloses,germination index(GI),and microflora structure were explored to evaluate the potential in accelerating maturity and nitrogen fixation by SMS *** results showed that the addition of SMS accelerated the heating rate,prolonged the high temperature time,and decreased organic matter,hemicellulose,and cellulose by 17.49%,23.61%,and 18.62%,*** GI reached 105.86%with SMS addition,while 74.17%was found in control treatment after *** changed the microbial community composition and increased the species ***,Clostridium XI and Azomonas were dominant bacteria,which increased the retention of nitrogen,promoted organic matter degradation and reduce compost *** study can provide a feasible strategy for nitrogen fixation in the field of organic waste recycling.

关键词： spent mushroom substrate conditioning agent nitrogen fixation humification quality aerobic composting

Development and Extension of An Aggregated Scale Model: Part 1–Background to ASMITA

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China Ocean Engineering 2016年第4期30卷 483-504页

作者： Ian TOWNEND zheng bing WANG Marcel STIVE Zeng ZHOU University of Southampton Southampton S0171B JUK TU Delfl Delft 2600.44The Netherlands Deltares Delft 2600 MHThe Netherlands Jiangsu Key Laboratory of Coast Ocean Resources Development and Environment Security Hohai UniversityNanjing 210098China

Whilst much attention has been given to models that describe wave, tide and sediment transport processes in sufficient detail to determine the local changes in bed level over a relatively detailed representation of the bathymetry, far less attention has been given to models that consider the problem at a much larger scale （e.g. that of geomorphological elements such as a tidal fiat and tidal channel）. Such aggregated or lumped models tend not to represent the processes in detail but rather capture the behaviour at the scale of interest. One such model developed using the concept of an equilibrium concentration is the Aggregated Scale Morphological Interaction between Tidal basin and Adjacent coast （ASMITA）. In this paper we provide some new insights into the concepts of equilibrium, and horizontal and vertical exchange that are key components of this modelling approach. In a companion paper, we summarise a range of developments that have been undertaken to extend the original model concept, to illustrate the flexibility and power of the conceptual framework. However, adding detail progressively moves the model in the direction of the more detailed process-based models and we give some consideration to the boundary between the two.

关键词： estuary tidal inlet morphology tides waves sediment transport

Influence of biosurfactant on the diesel oil remediation in soil-water system

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Journal of Environmental Sciences 2006年第3期18卷 587-590页

作者： LI Yu-ying zheng Xi-lai LI bing Department of Chemistry and Environmental Engineering Wuyi University Jiangmen 529020 China Institute of Environmental Science and Engineering Ocean University of China Qingdao 266003 China

There were six high diesel oil degrading bacteria strains isolated from the oil contaminated soil that collected from Linzi City. The strain YI was able to produce biosurfactant rhanmolipid when cultivated on diesel oil as carbon source. The critical micelle concentrations （CMC） of rhanmolipid in water and in the soil were measured respectively according to the correlation between the surface tension of the medium and the added rhamnolipid concentration. The results showed that the CMC of rhanmolipid in water was 65 mg/L, and was 185 mg/L in soil. The tests on diesel oil biodegradation were conducted with the addition of different concentrations of rhamnolipid in water and in soil respectively. When 0.01% rhanmolipid was added to water, the diesel oil degradation was enhanced. On the contrary, when the same concentration of rhanmolipid was added to the soil, the degradation of diesel oil was inhibited. The results suggested that the rhamnolipid could enhance the diesel oil biodegradation, indicating that the concentration of rhamnolipid was higher than the corresponding CMC in the medium. Kinetics parameters for the diesel oil biodegradation parameters such as biodegradation constant （λ）, coefficient of correlation （r） and half life （t1/2） in both tests were numerically analyzed in this paper, indicating that the moderate concentration of rhamnolipid in the medium could not only enhance the extent of diesel oil biodegradation but also shorten the time for oil remediation.

关键词： biosurfactant diesel oil remediation bacteria