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Structural vibration passive control and economic analysis of a high-rise building in Beijing

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 561-568页

作者： Chen Yongqi Cao tiezhu Ma Liangzhe Luo Chaoying Beijing Qitai Shock Control and Scientific Development Co. Ltd Beijing 10003 7 China John A. Martin ＆ Associates Inc. Los Angeles USA

Performance analysis of the Pangu Plaza under earthquake and wind loads is described in this paper. The plaza is a 39-story steel high-rise building, 191 m high, located in Beijing close to the 2008 Olympic main stadium. It has both fluid viscous dampers （FVDs） and buckling restrained braces or unbonded brace （BRB or UBB） installed. A repeated iteration procedure in its design and analysis was adopted for optimization. Results from the seismic response analysis in the horizontal and vertical directions show that the FVDs are highly effective in reducing the response of both the main structure and the secondary system. A comparative analysis of structural seismic performance and economic impact was conducted using traditional methods, i.e., increased size of steel columns and beams and/or use of an increased number of seismic braces versus using FVD. Both the structural response and economic analysis show that using FVD to absorb seismic energy not only satisfies the Chinese seismic design code for a ＂rare＂ earthquake, but is also the most economical way to improve seismic performance both for one-time direct investment and long term maintenance.

关键词： fluid viscous dampers (FVD) damping ratio secondary system One-time investment maintenance factor

A comparison of single- and multi-site calibration and validation： a case study of SWAT in the Miyun Reservoir watershed, China

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Frontiers of Earth Science 2017年第3期11卷 592-600页

作者： Jianwen BAI Zhenyao SHEN tiezhu YAN State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China

An essential task in evaluating global water resource and pollution problems is to obtain the optimum set of parameters in hydrological models through calibra- tion and validation. For a large-scale watershed, single-site calibration and validation may ignore spatial heterogeneity and may not meet the needs of the entire watershed. The goal of this study is to apply a multi-site calibration and validation of the Soil and Water Assessment Tool （SWAT）, using the observed flow data at three monitoring sites within the Baihe watershed of the Miyun Reservoir watershed, China. Our results indicate that the multi-site calibration parameter values are more reasonable than those obtained from single-site calibrations. These results are mainly due to significant differences in the topographic factors over the large-scale area, human activities and climate variability. The multi-site method involves the division of the large watershed into smaller watersheds, and applying the calibrated parameters of the multi-site calibration to the entire watershed. It was anticipated that this case study could provide experience of multi-site calibration in a large-scale basin, and provide a good foundation for the simulation of other pollutants in follow- up work in the Miyun Reservoir watershed and other similar large areas.

关键词： calibration soil and water assessment tool,Miyun Reservoir multi-site

Relationship between bacteria and phytoplankton during the giant jellyfish Nemopilema nomurai bloom in an oligotrophic temperate marine ecosystem

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Acta Oceanologica Sinica 2016年第10期35卷 107-113页

作者： ZENG Yang HUANG Xuguang HUANG Bangqin MI tiezhu Key Laboratory of Coastal and Wetland Ecosystems of Ministry of Education Xiamen University Fujian Provincial Key Laboratory of Coastal Ecology and Environmental Studies Xiamen University College of Chemistry and Chemical Engineering Ocean University of China

Bacterial abundance, phytoplankton community structure and environmental parameters were investigated to study the relationships between bacteria and phytoplankton during giant jellyfish Nemopilema nomurai blooms in the central Yellow Sea during 2013. N. nomurai appeared in June, increased in August, reached a peak and began to degrade in September 2013. Results showed that phosphate was possible a key nutrient for both phytoplankton and bacteria in June, but it changed to nitrate in August and September. Phytoplankton composition significantly changed that pico-phytoplankton relative biomass significantly increased, whereas other size phytoplankton significantly decreased during jellyfish bloom. In June, a significantly positive correlation was observed between chlorophyll a concentration and bacterial abundance（r=0.67, P0.001, n=34）.During jellyfish outbreak in August, there was no significant correlation between phytoplankton and bacteria（r=0.11, P0.05, n=25）, but the relationship（r=0.71, P0.001, n=31） was rebuilt with jellyfish degradation in September. In August, small size phytoplankton occupied the mixed layer in offshore stations, while bacteria almost distributed evenly in vertical. Chlorophyll a concentration significantly increased from（0.42±0.056） μg/L in June to（0.74±0.174） μg/L in August, while bacterial abundance just slightly increased. Additionally, the negative net community production indicated that community respiration was not entirely determined by the local primary productivity in August. These results indicated that jellyfish blooms potentially affect coupling of phytoplankton and bacteria in marine ecosystems.

关键词： jellyfish bloom Nemopilema nomurai phytoplankton pigments jellyfish DOM ecological consequence

Effects of Ocean Acidification on Nitrogen Metabolism of Skeletonema costatum

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Journal of Ocean University of China 2024年第5期23卷 1359-1370页

作者： WANG Shuxing MI tiezhu ZHEN Yu ZHU Jianbin Key Laboratory of Marine Environment and Ecology Ministry of EducationCollege of Environmental Science and EngineeringOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao Marine Science and Technology CenterQingdao 266237China Frontiers Science Center for Deep Ocean Multispheres and Earth System Ocean University of ChinaQingdao 266100China

Ocean acidification(OA),caused by the rising concentration of atmospheric CO_(2),leads to changes in the marine carbonate ***,in turn,affects the physiological processes of *** response to increased pCO_(2) levels,marine microalgae modulate their physiological responses to meet their energy and metabolic *** metabolism is a critical metabolic pathway,directly affecting the growth and reproductive capacity of marine *** the molecular mechanisms that regulate nitrogen metabolism in microalgae under OA conditions is therefore *** study aimed to investi-gate how OA affects the expression profiles of key genes in the nitrogen metabolic pathway of the marine diatom Skeletonema *** findings indicate that OA upregulates key genes involved in the nitrogen metabolic pathway,specifically those related to nitrate assimilation and glutamate ***,pCO_(2) has been identified as the predominant factor affecting the expression of these genes,with a more significant impact than pH variations in *** research not only advances our understanding of the adaptive mechanisms of *** in response to OA but also provides essential data for predicting the ecological consequences of OA on marine diatoms.

关键词： Skeletonema costatum ocean acidification nitrogen metabolism gene expression transcriptome

Characterization of Bacterial Communities in Aerosols over Northern Chinese Marginal Seas and the Northwestern Pacific Ocean in Autumn

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Journal of Ocean University of China 2023年第1期22卷 136-150页

作者： ZHANG Bo ZHEN Yu MI tiezhu QI Jianhua YUAN Gang Key Laboratory of Marine Environment and Ecology Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China

The characteristics of the bacterial community structure in aerosols of different particle sizes over northern Chinese marginal seas and the northwestern Pacific Ocean in autumn were analyzed using high-throughput sequencing and the quantitative real-time PCR method based on 16S rRNA *** with environmental factors and air mass sources,the bacterial abundance,community diversity,composition and structural characteristics in aerosols were studied,which might provide a scientific evaluation for a comprehensive understanding of the characteristics,long-distance transmission and ecological effects of aerosols from coastal waters to the distant ocean(northwestern Pacific Ocean).At the junction of the South Yellow Sea and the East China Sea,the bacterial abundance in the aerosols was substantially affected by transmission of continental air masses and was higher than those in other samples,and the bacterial abundance in coarse particle(>2.1μm)samples was significantly higher than that in fine particle(0.05).Among the environmental factors examined,a significant negative correlation was observed between bacterial community richness and temperature(P<0.05),and the bacterial community diversity was significantly positively correlated with the concentration of K^(+)(P<0.05).Canonical correspondence analysis showed that temperature,NH_(4)^(+) concentration and SO_(4)^(2−) concentration exerted significant effects on bacterial community struc

关键词： bioaerosol marine environment community structure particle size

Perspectives on electrochemical nitrogen fixation catalyzed by two-dimensional MXenes

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Materials Reports(Energy) 2022年第1期2卷 3-16页

作者： tiezhu Guo Di Zhou Chuanfang(John)Zhang Laboratory for Functional Polymers EmpaSwiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 129CH-8600DübendorfSwitzerland Key Laboratory of Multifunctional Materials and Structures Ministry of EducationSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an710049ShaanxiPR China

Ammonia is the most basic raw material in industrial and agricultural *** current industrial production of ammonia relies on the Haber-Bosch process with high energy *** overcome this shortcoming,the development of electrocatalytic ammonia synthesis under moderate conditions is considered as a potential alternative *** two-dimensional(2D)MXenes family has been proved promising as electrocatalysts,but from the currently available literature,it is hard to find a systematic review on MXenes-catalyzed ammonia *** in the present review,we summarize the key perspectives on that topic in recent years as well as outline,from a prospective view,strategies of catalyst *** analyze in detail the methods for preparing high performance MXenes-based catalysts and the corresponding underlying mechanisms,and also discuss the criteria and potential challenges,expecting to provide inspiration for the development of efficient MXenes-based route to electrochemical ammonia fixation.

关键词： 2D materials MXenes Ammonia synthesis Electrocatalytic nitrogen reduction reaction (NRR) Electrocatalysts

Asexual Reproduction of Aurelia coerulea Polyps in situ on Settling Plates in Jiaozhou Bay,China

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Journal of Ocean University of China 2024年第5期23卷 1371-1380页

作者： MI tiezhu ZHU Jianbin ZHEN Yu WANG Guoshan WANG Jianyan Key Laboratory of Marine Environment and Ecology Ministry of EducationCollege of Environmental Science and EngineeringOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao Marine Science and Technology CenterQingdao 266237China Frontiers Science Center for Deep Ocean Multispheres and Earth System Ocean University of ChinaQingdao 266100China National Marine Hazard Mitigation Service Ministry of Natural ResourcesBeijing 100194China Department of Life Sciences National Natural History Museum of ChinaBeijing 100050China

Jellyfish blooms are increasingly prevalent coastal phenomena,with Aurelia coerulea being a significant *** complex life history of jellyfish,featuring a sessile polyp stage,is a key factor in bloom formation,yet it is challenging to study in the *** study aimed to describe the asexual reproduction of *** polyps in Jiaozhou Bay,China,and to assess their ability to form sedentary colonies and their relationship with environmental *** settling plates,we observed polyps in situ and documented three asexual reproduction modes:budding,strobilation,and podocyst *** parameters including temperature,salinity,dissolved oxygen(DO),chlorophyll a(Chl a),and the biomass of phytoplankton and zooplankton were *** was the predominant reproductive method,featuring stolon budding in autumn and direct budding during the winter and spring *** took place in the colder months,releasing ephyrae between April and *** abundance was positively correlated with seawater temperature and negatively correlated with DO *** at 1.0 m depth showed higher survivorship and proliferation over 8 months,whereas those at 2.0 m depth experienced a steady decline and died within 4 *** study enhances our understanding of the life cycle and asexual reproduction strategies of *** polyps in the field,with implications for predicting and managing jellyfish *** findings underscore the importance of temperature and DO in polyp survival and suggest that initial polyp population proliferation is crucial for long-term survival.

关键词： jellyfish bloom polyps budding strobilation asexual reproduction

Molecular monitoring plankton community during jellyfish blooms in the water near the Liaoning Hongyan River Nuclear Power Plant

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Journal of Oceanology and Limnology 2023年第5期41卷 1781-1794页

作者： Ming YUE tiezhu MI Ying LI Xianyu GONG Yu ZHEN Key Laboratory of Marine Environment and Ecology Ocean University of ChinaMinistry of EducationQingdao 266100China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China

The Liaoning Hongyan River Nuclear Power Plant is located on the east coast of Liaodong Bay in the Bohai Sea,China,and the safety of the cooling water is often threatened by large-scale jellyfish ***,monitoring jellyfish growth,migration,and disappearance is essential to the safety of the nuclear power *** this study,high-throughput sequencing was used to analyze the community characteristics of mesoplankton in the sea area at the inlet and outlet from April to September *** the same time,the micro-individuals of jellyfish(including oosperm,planula,polyps,or ephyra of jellyfish)in the water were detected by real-time fluorescent quantitative PCR(qPCR).Both the maximum abundance of Aurelia coerulea and Nemopilema nomurai in July were detected by high-throughput sequencing and q *** three common taxa of plankton(Paracalanus,Calanoida,and Poaceae)were found in the waters near the inlet and outlet,and the beta diversity of plankton in the waters near the inlet and outlet was low in the same *** on the plankton community composition in the sea water near the inlet,it could be speculated that jellyfish outbreaks would have a significant impact on the plankton via the predation *** maximum mt-16S rDNA copy numbers of *** and *** in the samples from the waters of Liaodong Bay were detected in June 2019,and that of *** showed an increasing trend from north to south,with the jellyfish tending to move to the seawaters near the *** results indicate that the optimum monitoring period for jellyfish outbreaks in Liaodong Bay is from the end of May to the end of July.

关键词： jellyfish Aurelia coerulea Nemopilema nomurai molecular monitoring community

Influence of N, P, Fe Nutrients Availability on Nitrogen Metabolism-Relevant genes Expression in Skeletonema marinoi

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Journal of Ocean University of China 2019年第1期18卷 239-252页

作者： JING Xiaoli MI tiezhu ZHEN Yu WANG Hualong YU Zhigang College of Marine Life Science Ocean University of China Function Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology Key Laboratory of Marine Environment and Ecology Ministry of Education College of Environmental Science and Engineering Ocean University of China Key Laboratory of Marine Chemical Theory and Technology Ministry of Education

Nitrogen(N), Phosphorus(P), and Iron(Fe) are essential elements for cellular structure and metabolism. In addition to dissolved inorganic nitrogen(DIN), phytoplankton is able to utilize dissolved organic nitrogen(DON). There is general consensus that both bacteria and higher plants nitrogen metabolism is affected by phosphate availability; this was also found to be true in coccolithophorid. Iron affects the structure and function of ecosystems through its effects on nitrogen metabolism. However, it is unclear how these nutrients affect Skeletonema marinoi's nitrogen metabolism. Here, using RT-qPCR, we investigate effects of N, P, and Fe on S. marinoi's nitrogen metabolism and nitrate reductase activity. These results illuminate that in S. marinoi, various nutrients have direct regulation on these genes expression at the molecular level. The varying degree of responses for these genes expression with differing N sources may act to increase the efficiency of nutrient capture when nitrate is limited. Suitable gene expression occurs at a N/P ratio of 16, which represents the atomic N/P ratio of phytoplankton cells and N/P concentrations in ocean; thus, nitrogen metabolism gene expression should be regulated by the existing N/P ratios in the phytoplankton's internal and external environment. Fe concentration has a direct and significant effect on nitrogen metabolism by regulating gene expression and nitrate reductase activity. gene expression profiles identified in S. marinoi provide a foundation for understanding molecular mechanisms behind diatom nitrogen metabolism with changing N, P, and Fe nutrients allowing a basic understanding of how diatom growth is affected by nutrient utilization.

关键词： Skeletonema marinoi nitrogen metabolism relative gene expression RT-qPCR