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Time-Domain Nonlinear Wave-Current Interaction with A Steep Wave Riser Considering Internal Flow Effect

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China Ocean Engineering 2021年第3期35卷 410-421页

作者： TANG lian-yang CHENG Yong JI Chun-yan School of naval architecture and ocean engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Nippon Kaiji Kyokai(China)Co. LtdShanghai 200336China

The nonlinear dynamic response induced by the wave-current interaction on a deepwater steep wave riser(SWR)is numerically investigated based on a three-dimensional(3 D)time-domain finite element method(FEM).The governing equation considering internal flow is established in the global coordinate *** whole SWR consists of three segments:the decline segment,buoyancy segment and hang-off segment,in which the buoyancy segment is wrapped by several buoyancy modules in the middle section,leading to the arch bend and sag bend.A Newmark-β iterative scheme is adopted for the accurate analysis to solve the governing equation and update the dynamic response at each time *** proposed method is verified through the published results for the dynamic response of steel catenary riser(SCR)and static configuration of steel lazy wave riser(SLWR).Simulations are executed to study the influence of wave height,current velocity/direction,internal flow density/velocity and top-end pressure on the tension,configuration and bending moment of the *** results indicate that the influence of the current on the configuration and mechanical behavior of the SWR is greater than that of the wave,especially in the middle *** increasing current velocity,the suspending height of the middle section drops,meanwhile,its bending moment decreases accordingly,but the tension increases *** a fixed external load,the increasing internal flow density induces the amplification of the tension at the hang-off segment and the mitigation at the decline segment,while the opposite trend occurs at the bending moment.

关键词： steep wave riser(SWR) nonlinear dynamic response wave-current interaction time-domain finite element method(FEM)

Nonlinear Analysis of Bidirectional Vortex-Induced Vibration of A Deepwater Steep Wave Riser Subjected to Oblique Currents

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China Ocean Engineering 2021年第6期35卷 852-865页

作者： CHENG Yong TANG lian-yang JI Chun-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Nippon Kaiji Kyokai(China)Co. LtdShanghai 200336China

An improved three-dimensional(3D)time-domain couple model is established in this paper to simulate the bidirectional vortex-induced vibration(VIV)of a deepwater steep wave riser(SWR)subjected to oblique *** this model,the nonlinear motion equations of the riser are established in the global coordinate system based on the slender rod theory with the finite element *** der Pol equations are used to describe the lift forces induced by the x-and y-direction current components,*** coupled equations at each time step are solved by a Newmark-βiterative scheme for the SWR *** present model is verified by comparison with the published experimental results for a top-tension ***,a series of simulations are executed to determine the influences of the oblique angle/velocity of the current,different top-end positions and the length of the buoyancy segment on the VIV displacement,oscillating frequency as well as hydrodynamic coefficients of the *** results demonstrate that there exists a coupled resonant VIV corresponding to x-direction and y-direction,***,the effective frequency is almost identical between the vibrations at the hang-off segment along x and y *** addition of the buoyancy modules in the middle of the SWR has a beneficial impact on the lift force of three segments and simultaneously limits the VIV response,especially at the decline segment and the hang-off ***,the incident current direction significantly affects the motion trajectory of the SWR which mainly includes the fusiform and rectangle shapes.

关键词： steep wave riser(SWR) bidirectional vortex-induced vibration wake oscillator model time-domain finite element method(TDFEM)

Impacts of advanced treatment processes on elimination of antibiotic resistance genes in a municipal waste water treatment plant

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 69-78页

作者： lian yang Qinxue Wen Zhiqiang Chen Ran Duan Pan yang State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology (SKLUWRE HIT) Harbin 150090 China National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology Suzhou University of Science and Technology Suzhou 215009 China

Antibiotic resistance genes (ARGs) pose a serious threat to public health. Wastewater treatment plants (WWTPs) are essential for controlling the release of ARGs into the environment. This study investigated ARG distribution at every step in the treatment process of a municipal WWTP located in Harbin for six consecutive months. Changes in ARG distribution involved in two advanced secondary effluent treatment processes, ozonation and granular activated carbon (GAC) adsorption, were analyzed. Biological treatment resulted in the highest ARG removal (0.76-1.94 log reduction), followed by ultraviolet (UV) disinfection (less than 0.5-log reduction). Primary treatment could not significantly remove ARGs. ARG removal efficiency increased with an increase in the ozone dose below 40 mg/L. However, amorphous GAC (AGAC) adsorption with a hydraulic retention time (HRT) of 1 h showed better removal of ARGs, total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) than ozonation at a 60 mg/L dose. UV treatment could efficiently reduce the relative ARG abundance, despite presenting the lowest efficiency for the reduction of absolute ARG abundance compared with GAC and ozone treatments. The combination of ozone and AGAC can significantly improve the removal of ARGs, TOC, TN and TP. These results indicate that a treatment including biological processing, ozonation, and AGAC adsorption is a promising strategy for removing ARGs and refractory organic substances from sewage.

关键词： Antibiotic resistance genes (ARGs) Wastewater treatment plant (WWTP) Ultraviolet (UV) Ozonation Granular activated carbon (GAC)

Insecticidal activities of garlic substances against adults of grain moth, Sitotroga cerealella （Lepidoptera： Gelechiidae）

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Insect Science 2012年第2期19卷 205-212页

作者： Feng-lian yang Fen Zhu Chao-liang Lei Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory Huazhong Agricultural UniversityWuhanChina

The angoumois grain moth, Sitotroga cerealella （Olivier）, is one of the most serious stored grain pests around the world. In attempts to reduce the losses caused by the moth and to suppress its populations, the fumigant activities, behavioral influence and ovipositional inhibition of garlic （Allium sativum） essential oil and its two major components, diallyl disulfide and diallyl trisulfide, were investigated against the adult grain moth. Their effects on reduction in survival of first instar larvae to adult emergence were also evaluated. Results showed that these three materials （garlic essential oil, diallyl disulfide and diallyl trisulfide） had significant fumigant activity with 50% lethal concentration values at 1.33, 0.99, and 1.02/zL/L air space, respectively; meanwhile, the three materials possessed high behavioral deterrent activities against adults in the Y-tube olfactometer. When applied to rice grains, these materials reduced adult longevity and inhibited oviposition, with ovipositional inhibition above 70% at a concentration of 1.5uL/25 g in either no-choice or two-choice tests. In short, the study showed that both diallyl disulfide and diallyl trisulfide, like garlic essential oil, acted as fitrnigants, produced behavioral deter- rence and inhibited oviposition against angoumois grain moth. Our work here indicates that diallyl disulfide and diallyl trisulfide may serve as potential alternatives for grain protectants since both of them can be prepared easily from readily available chemicals.

关键词： behavioral deterrence essential oil fumigant garlic oviposition inhibition,Sitotroga cerealella

Best bounds on the distance between 3-direction quartic box spline surface and its control net

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Applied Mathematics(A Journal of Chinese Universities) 2013年第2期28卷 147-157页

作者： ZENG Xiao-ming ZHOU Guo-rong yang lian-qiang Department of Mathematics Xiamen University School of Mathematics Anhui University

We present the best bounds on the distance between 3-direction quartic box spline surface patch and its control net by means of analysis and computing for the basis functions of 3-direction quartic box spline *** the local bounds and the global bounds are given by the maximum norm of the first differences or second differences or mixed differences of the control points of the surface patch.

关键词： Box spline bound parametric surface basis function differences of control point.

Preparation of straw superabsorbent composite material by microwave method

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Preparation of straw superabsorbent composite material by mi...

Ecological risk assessment and ecological security pattern optimization in the middle reaches of the Yellow River based on ERI+MCR model

第八届中国功能材料及其应用学术会议

作者： yang lian-wei WANG Rui-jie School of Resources and Materials Northeastern University at Qinhuangdao Branch

ISBN: (纸本)9783037859698

By microwave method,a superabsorbent function composite material was prepared by grafting sodium acrylate onto straw flour using potassium persalfate(KSO) and N,N’-methylene bis acrylamide as an initiator and crosslinker,*** effect of various preparation conditions on its water absorbency was *** the straw flour content was 6%,the acrylic acid content was 20.0g,the amount of initiator was 0.4%,the neutralization degree of monomer was 80%,the reaction temperature was 70℃ and the amount of crosslinker was 0.05%,the material’s absorbency was 1360 times in distilled water and 152 times in 0.9%salt-water at ambient *** had also high water *** analyses of SEM indicate that sodium acrylate is grafted on the polysaccharides of straw flour.

关键词： Straw superabsorbent polymer preparation characterization

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Journal of Geographical Sciences 2023年第4期33卷 823-844页

作者： yang lian'an LI Yali JIA Lujing JI Yongfan HU Guigui Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi'an 710127China Yellow River Institute of Shaanxi Province Northwest UniversityXi'an 710127China College of Urban and Environmental Sciences Northwest UniversityXi'an 710127China

The middle reaches of the Yellow River represent an important area for the protection and development of the Yellow River *** of the area of the river basin is within the Loess Plateau,which establishes it as a fragile ecological ***,using high-resolution data of land use in the watershed from the past 30 years,landscape ecological risk(LER)sample units are defined and an ecological risk index(ERI)model is *** interpolation is used to display the LER spatial patterns,and the temporal and spatial evolution of risk is ***,the spatial evolution of land use landscape change(LULC)is analyzed,and the correlation between land use landscape and ecological risk is ***,Based on the LER model,a risk-based minimum cumulative resistance(MCR)model is established,and a comprehensive protection and management network system for the ecological source-corridor-node system *** results suggest that in the past 30 years,LER has a high spatial correlation and areas with extremely high ecological risks are concentrated in northwest and southeast areas of the region,of which the northwest area accounts for the highest *** intensity is closely related to the spatial pattern of land use *** values of forestland,grasslands,and unused land and farmland are low,medium,and high,*** trend of risk evolution is“overall improvement and partial deterioration”.Man-made construction and exploitation is the most direct reason for the increase of local ecological *** high ecological-risk areas in the northwest are dominated by deserts which reduce excessive interference by human activities on the natural *** are:high-quality farmland should be protected;forestland should be restored and rebuilt;repair and adjust the existing ecosystem to assist in landscape regeneration and reconstruction;utilize the overall planning vision of“mountain,water,forest,field,lake,grass,sa

关键词： landscape ecological risk MCR model ecological security pattern middle reaches of the Yellow River

Reformation of the Judicial Appraisal Adoption System used by Party Institutions Entrusted by the Investigation Agency in Criminal Proceedings

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Journal of Forensic Science and Medicine 2019年第4期5卷 208-212页

作者： yang lian Mengshang Wu Yuanyuan lian Changping District People’s Court of Beijing BeijingChina Institute of Evidence Law and Forensic Science China University of Political Science and LawBeijingChina Collaborative Innovation Centers of Judicial Civilization BeijingChina Institute of Evidence Law and Forensic Science Key Laboratory of Evidence ScienceMinistry of Education(China University of Political Science and Law)BeijingChina Institute of Evidence Law and Forensic Science Fada Institute of Forensic Medicine and ScienceBeijingChina Institute of Evidence Law and Forensic Science Institute of Evidence Law and Forensic ScienceChina University of Political Science and LawBeijingChina

The new requirements of trial-centered litigation in China are a concrete manifestation of the reform of the rule of law under Xi Jinping’s new socialist *** effective implementation of judicial appraisal lays a solid foundation for the correct identification of facts,accurate conviction,and sentencing,and technically,it should guarantee a fair ***,in practice,judicial appraisal opinion carries the risk of a diminished trial that deviates from the trial-centered requirement to substantiate a charge and can easily lead to unjust *** paper seeks to discuss the system of identification of property loss involved in criminal proceedings,which is implemented by a third‑party appraisal institution entrusted by the investigation agency,and highlights the fact that the third-party appraisal institutions in judicial practice are currently reliant on cooperative thinking,but countenance the lack of a mechanism for effective accountability,and the court’s propensity for *** leads to the verification components of the trial being depreciated,which may lessen the validity of the appraisal opinion(substantiation).In response to this problem,the author hopes to provide some suggestions to assist third-party appraisal agencies in the completion of judicial appraisal and achievement of their trial‑centered reform goal by rationalizing the relationship between the investigation agency and identification institution,establishing a hierarchical accountability mechanism,and improving the rules governing testimony in court.

关键词： Appraisal opinions criminal litigation judicial appraisal trial centered trial substantiation

Decomposition of Al_(13) promoted by salicylic acid under acidic condition: Mechanism study by differential mass spectrometry method and DFT calculation

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Journal of Environmental Sciences 2023年第4期126卷 423-433页

作者： Guangyu An Ye Yue lian yang Hailu Demissie Ruyuan Jiao Jinyang Xi Dongsheng Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Faculty Water Conservancy and Hydropower Engineering North China Electric Power UniversityBeijing 10220China Department of Chemistry Arba Minch UniversityArba Minch 021Ethiopia yangtze River Delta Branch Research Center for Eco-Environmental SciencesChinese Academy of SciencesZhejiang 322000China Materials Genome Institute Shanghai UniversityShanghai 200444China College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China

Decomposition of the polycation Al_(13)O_(4)(OH)_(2)4(H_(2)O)_(12)^(7+)(Al_(13)) promoted by ligand is a vital subject to advance our understanding of natural and artificial occurrence and evolution of aluminum ions,especially in the case of acidic condition that dissolved Al^(3+)species can be released from the Al-bearing ***,the microscopic pathway of synchronous proton-promoted and ligand-promoted decomposition process for Al_(13)is still in the status of ***,we applied differential mass spectrometry method and DFT calculation to study the initial detailed process of Al_(13)decomposition under the presence of proton and salicylic acid (H_(2)Sal).Mass results showed that the mononuclear Al^(3+)-H_(2)Sal complexes dominated the resulting Al species,whereas the monodentate complex Al_(13)HSal6+was not observed in the *** difference of decomposition levels between the ligand/Al ratio 0.2 and 0.5 cases revealed that proton and ligand performed synergistic effect in initial Al_(13)decomposition process,and the proton transfer determined the ring closure *** ring closure reaction is the prerequisite for the collapse of Al_(13)structure and detachment of the mononuclear *** calculations reveal that hydrogen bond plays an important role in inducing the formation of chelated complex accompanying proton *** of protons at the bridging OH^(-)can elongate and weaken the critical bond between targeted Al^(3+)and μ4-O_(2)-resulting from delocalization of electron pairs in the oxygen *** results demonstrate the detailed mechanism of Al_(13)composition promoted by ligand and proton,and provide significant understanding for further application and control of Al_(13).

关键词： Al_(13) Differential mass spectrometry Density functional calculation Complex Ring closure Decomposition