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Journal of Environmental Sciences 2005年第4期17卷 611-614页

作者： YUShui-li LIUYa-nan JINGGuo-lin ZHAOBing-jie GUOSi-yuan SchoolofMunicipalandEnvironmentalEngineering HarbinInstituteofrechnologyHarbin150090China.

To investigate the microbial communities of microorganisms cultivated under different carbon sources, three sequencing batch reactors were operated. They were supplied with sewage, glucose and sodium acetate as carbon sources respectively and showed high phosphorus removal performance. The results of denaturing gradient gel electrophoresis(DGGE) of polymerase chain reaction-amplified(PCR) 16S rDNA fragments demonstrated that β-protebacteria, Actinomyces sp. and γ-protebacteria only exited in 1# reactor. The microbiological diversity of 1# reactor exceeded the other two reactors. Flavobacterium, Bacillales, Actinomyces, Actinobacteridae and uncultured bacteria(AF527584, AF502204, AY592749, AB076862, AJ619051, AF495454 and AY133070) could be detected in the biological phosphorus removal reactors.

关键词： 16S rDNA carbon source biological phosphorus removal PCR-DGGE

Characteristics of frequency content of near-fault ground motions during the Chi-Chi earthquake

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Acta Seismologica Sinica(English Edition) 2005年第6期18卷 707-716,750页

作者：徐龙军谢礼立 School of Civil Engineering Harbin Institute of Technology Harbin 150090 China School of Civil Engineering Harbin Institute of Technology Harbin 150090 ChinaInstitute of Engineering Mechanics China Earthquake Administration Harbin 150080 China

The frequency content of earthquake ground motion is very important because it affects the dynamic response of structural systems. In the paper, we use five scalar parameters (the response spectral predominant period Tp, smoothed spectral predominant period To, Fourier amplitude spectral mean period Tm, equivalent pulse period Tv, and the pseudo-velocity spectral predominant period Tpv) reflecting the characteristics of frequency content of strong ground motion to examine the near-fault three-component motions during the 1999 Chi-Chi earthquake. The result indicates that the frequency content of near-fault motions at the Hanging wall is less than that at the foot wall; Tp shows a smaller value than that of To and Tm and it emerges a reverse relation of three-component motions as compared with that of To and Tm; Tv and Tpv of the near-fault motions at the north end of the rupture display a similar trend to that generated by the rupture directivity effect of strike-slip faulting. We therefore conclude that these observations are useful in the formulation of near-fault design spectra for seismic codes and in zoning studies in seismic risk.

关键词： frequency content directivity effect hanging-wall effect Chi-Chi earthquake

Analysis of coherent structures in drag-reducing polymer solution flow based on proper orthogonal decomposition

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Science China(Physics,Mechanics & Astronomy) 2012年第5期55卷 854-860页

作者： CAI WeiHua LI FengChen ZHANG HongNa WANG Yue WANG Lu School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Civil Engineering Harbin Institute of Technology Harbin 150090 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Direct numerical simulation(DNS) of forcing homogeneous isotropic turbulence with polymers was *** order to understand the polymers effect on turbulent coherent structures,proper orthogonal decomposition was performed to identify coherent structures based on DNS data,so as to analyze the remarkable difference due to the addition of *** results showed that the numbers for eigenmodes required for capturing coherent structures were 32 and 24 for the Newtonian fluid and polymer solution flows,respectively,which means the decrease of the complexity in polymer solution *** the POD energy spectrum,it was found that the turbulent kinetic energy is distributed onto a large number of eigenmodes whether in the Newtonian fluid flow or polymer solution flow,suggesting that polymer solution flow is still turbulent in one ***,the POD eigenmodes were investigated,which found that the small-scale structures are inhibited in polymer solution flow.

关键词： coherent structures polymer drag reduction isotropic turbulence proper orthogonal decomposition

Formaldehyde degradation by UV/TiO_2/O_3 process using continuous flow mode

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Journal of Environmental Sciences 2007年第9期19卷 1136-1140页

作者： QI Hong SUN De-zhi CHI Guo-qing School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China.

The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount on degradation of formaldehyde gas were investigated. The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action, e.g,, it could considerably increase decomposing of formaldehyde. The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84--24 mg/m^3 by O3/TiO2flJV process. The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m^3. Furthermore, the kinetics of formaldehyde degradation reaction could be described by Langmuir-Hinshelwood model. The rate constant k of 46.72 mg/（m^***） and Langmuir adsorption coefficient K of 0.0268 m^3/mg were obtained.

关键词： UV/TiO2/O3 process formaldehyde continuous flow mode

Experimental investigation on cenosphere-aluminum syntactic foam-filled tubes under axial impact loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第11期24卷 978-990页

作者： Li WANG Boyi ZHANG Jian ZHANG Yuexin JIANG Wei WANG Gaohui WU School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Center for Metal Matrix Composites Engineering Technology Harbin Institute of TechnologyHarbin 150006China

A new syntactic foam material was prepared by screening three different average particle sizes of cenospheres(150,200,and 300μm)from industrial waste fly *** impact testing on syntactic foam filler and foam-filled tubes was conducted using a drop hammer test *** effects of parameters,such as the size of cenospheres and the impact velocity,on the mechanism of deformation,mechanical characteristics,and capacity for energy absorption of the specimen were *** this basis,the differences in compressive properties exhibited by the syntactic foam-filled tubes under the two loading conditions were *** results indicate that with the decrease in the average diameter of cenospheres,the initial peak crushing load and mean crushing load of foam-filled tubes increase,while the compression efficiency *** specific energy absorption(SEA)of the syntactic foam-filled tube can reach 25 J/*** the increase of impact velocity,the SEA of the specimen increases *** was demonstrated that the syntactic foam-filled tube exhibits a higher effective energy absorption ratio under impact loading compared to quasi-static loading.

关键词： Cenosphere-aluminum syntactic foam Crashworthiness Mechanical properties Absorption of energy

Field experiment on train-induced embankment vibration responses in seasonally-frozen regions of Daqing,China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 596-605页

作者： Xian-zhang LING Li-na WANG Feng ZHANG Shi-jun CHEN Zhan-yuan ZHU School of Civil Engineering Harbin Institute of Technology Harbin 150090 China Institute of Subgrade and Protection Engineering Harbin Institute of Technology Harbin 150090 China Information and Engineering Technology College Sichuan Agricultural University Ya 'an 625014 China

The seasonal-frozen layer may have an influence on embankment motion from train-induced vibrations. Based on the field monitoring in a seasonally-frozen region of northeastern China, the effects of the frozen layer on the embankment responses to train-induced vibration were investigated in winter and summer via acceleration time histories and acceleration frequency spectrums. The results show that: (1) Compared to unfrozen soil conditions, the amplitudes of longitudinal and vertical vibrations at the points near the rail were increased, different influences of freight versus high-speed trains are the most evident. (2) With greater distance from the rail, the dominant frequency ranges of embankment with both frozen and unfrozen layers narrowed and shifted to low frequency bands. (3) The predominant frequency of embankment vibration with frozen soil layers shifted to higher frequencies with the increased train speed, although there was little change with unfrozen condition. Layer condition (frozen versus unfrozen) and distance to rail both play important roles in investigating the embankment vibration characteristics and rail transit field monitoring to improve the criterion of the rail construction in seasonally-frozen regions.

关键词： Embankment vibration Spectrum characteristics Time histories Field monitoring. Seasonally-frozen re^ion

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区域医疗系统抗震韧性综述

哈尔滨工业大学学报 2025年第1期57卷 1-12页

作者：裴顺顺翟长海胡杰结构工程灾变与控制教育部重点实验室(哈尔滨工业大学) 哈尔滨150090 土木工程智能防灾减灾工业和信息化部重点实验室(哈尔滨工业大学) 哈尔滨150090

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通... 详细信息

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通系统的安全性、应急响应能力、多系统的整合与协作,有效评估区域医疗系统的抗震韧性水平,并提出科学的改进建议,对建设韧性城乡具有重要的理论意义。本文通过梳理国内外文献,阐明了区域医疗系统韧性的概念和内涵,总结了地震后短期应急和长期修复两个阶段韧性评估的重点,归纳了现有区域医疗系统韧性的评估框架,从医院集群系统、面向医疗的交通系统、应急医疗服务系统和医疗-交通耦合系统4个方面阐述了现有评估方法。区域医疗系统韧性的研究旨在提高其面对灾害时的抵抗性、短期适应性和长期恢复性,这些研究对于满足紧急和日常的医疗需求以及指导灾后恢复具有重要意义。目前区域医疗系统抗震韧性的研究取得了一些进展,但仍然存在一些挑战,本文最后展望了未来的研究方向。

关键词：区域医疗系统单体医院交通系统抗震韧性功能评估恢复时间

A sophisticated simulation for the fracture behavior of concrete material using XFEM

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 859-881页

作者： Zhai Changhai Wang Xiaomin Kong Jingchang Li Shuang Xie Lili School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Key Lab of Structures Dynamic Behavior and Control(harbin Institute of Technology) Ministry of EducationHeilongjiangHarbin 150090China Institute of Engineering Mechanics China Earthquake AdministrationHarbin 150080China

The development of a powerful numerical model to simulate the fracture behavior of concrete material has long been one of the dominant research areas in earthquake engineering. A reliable model should be able to adequately represent the discontinuous characteristics of cracks and simulate various failure behaviors under complicated loading conditions. In this paper, a numerical formulation, which incorporates a sophisticated rigid-plastic interface constitutive model coupling cohesion softening, contact, friction and shear dilatation into the XFEM, is proposed to describe various crack behaviors of concrete material. An effective numerical integration scheme for accurately assembling the contribution to the weak form on both sides of the discontinuity is introduced. The effectiveness of the proposed method has been assessed by simulating several well-known experimental tests. It is concluded that the numerical method can successfully capture the crack paths and accurately predict the fracture behavior of concrete structures. The influence ofmode-Ⅱ parameters on the mixed-mode fracture behavior is further investigated to better determine these parameters.

关键词： fracture behavior concrete material earthquake engineering interface constitutive model XFEM

Study on strength reduction factors consid-ering the effect of classification of design earthquake

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Acta Seismologica Sinica(English Edition) 2006年第3期19卷 299-310页

作者：翟长海谢礼立 School of Civil Engineering Harbin Institute of Technology Harbin 150090 China School of Civil Engineering Harbin Institute of Technology Harbin 150090 China Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China

The strength reduction factors are not only the key factors in determining seismic action for force-based seismic design, but also the key parameters to derive the inelastic response spectra for performance-based seismic design. In this paper, with a high quality ground motion database that includes a reasonable-sized set of records from China, a statistical study on the strength reduction factors is conducted and a new expression of strength reduction factors involving classification of design earthquake, which is an important concept to determine design spectra in Chinese seismic design code, is proposed. The expression of strength reduction factors can reflect the ground motion characteristics of China to a certain extent and is particularly suitable for Chinese seismic design. Then, the influence effects of site condition, classification of design earthquake, period of vibration, ductility level, earthquake magnitude and distance to fault on strength reduction factors are investigated. It is concluded that the effect of site condition on the strength reduction factors cannot be neglected, especially for the short-period structures of higher ductility. The classification of design earthquake also has an important effect on strength reduction factors and it may be unsuitable to use the existing expressions of strength reduction factors to the design spectra of current Chinese seismic code. The earthquake magnitude has no practical effect on strength reduction factors and if the near-fault records with forward directivity effect are not taken into consideration, the effect of distance to fault on strength reduction factors can also be neglected.

关键词： strength reduction factor site condition classification of design earthquake strong ground motion regression analysis

Effects of phosphorus and nitrogen limitation on PHA production in activated sludge

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Journal of Environmental Sciences 2010年第10期22卷 1602-1607页

作者： Qinxue Wen,Zhiqiang Chen,Ting Tian,Wei Chen State Key Laboratory of Urban Water Resource and Environment,harbin Institute of Technology,harbin 150090,China [a] State Key Laboratory of Urban Water Resource Environment Harbin Institute of Technology Harbin 150090 China

The effects of phosphorus and nitrogen limitation on polyhydroxyalkanoate （PHA） production and accumulation by activated sludge biomass with acetate as a carbon source were investigated. Pre-selected influent carbon-phosphorus （C：P, W/W） of 100, 160, 250, 500 and 750, and carbon-nitrogen （C：N, W/W） of 20, 60, 100, 125 and 180 were applied in the phosphorus limitation experiments and the nitrogen limitation experiments, respectively. The maximum PHA accumulation up to 59% of the cell dry weight with a PHA productivity of 1.61 mg PHA/mg COD consumed was observed at the C：N 125 in the nitrogen limitation experiment. This value was much higher than that obtained in previous studies with a normal substrate feeding. The study showed that activated sludge biomass would produce more polyhydroxybutyrate than polyhydroxyvalerate under the stress of nutrient limitation, especially under phosphorus limitation conditions. The experimental result also indicated that both phosphorus and nitrogen limitation may cause sludge bulking.

关键词： polyhydroxyalkanoate acetate nitrogen limitation phosphorus limitation sludge bulking