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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： Li Yuchun Shen chao liu wei Li Dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

Transient Stability Analysis and Design of VSGs with Different DC-Link Voltage Controllers

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 593-604页

作者： chao Shen wei Gu Wanxing Sheng Keyan liu School of Electrical Engineering Southeast UniversityNanjingChina Power Distribution Research Department China Electric Power Research InstituteBeijing 100192China

Virtual synchronous control has been widely studied for the advantages of emulating inertia for voltage source converters (VSCs). A constant dc-link voltage is usually assumed in existing literature to estimate transient stability of virtual synchronous generators (VSGs). However, actual power supply in the dc-side of VSGs is limited and different dc-link voltage controllers are needed to achieve power balance between DC side and AC side. Addition of dc-link voltage controller has great influence on transient behavior of VSGs, which has not been investigated by previous research. To fill this gap, this paper gives insights into the effect of dc-link voltage dynamics on transient stability of VSGs. First, two typical kinds of VSGs with dc-link voltage controllers are introduced. Then, mathematical models considering dc-link dynamics are established and the effect of dc-link voltage controllers on transient synchronization stability of VSGs is revealed through equal area criterion (EAC). It is found that dc-link voltage controller would reduce stability margin of VSGs and design-oriented transient stability analysis is carried out quantitively using critical clearing time (CCT). Finally, simulation results are given to validate correctness of theoretical analysis.

关键词： DC-link voltage dynamics equal area criterion(eac) transient synchronization stability virtual synchronous generator(VSG)

Clinical application of COVID-19 vaccine in liver transplant recipients

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 339-343页

作者： Feng-chao liu Man Xie wei Rao Division of Hepatology Liver Disease CenterThe Affiliated Hospital of Qingdao UniversityQingdao 266000China Organ Transplantation Center The Affiliated Hospital of Qingdao UniversityQingdao 266000China Institute of Organ Donation and Transplantation of Qingdao University Qingdao 266000China Department of Gastroenterology The Affiliated Hospital of Qingdao UniversityQingdao 266000China

Background:Solid organ transplant(SOT)activities,such as liver transplant,have been greatly influenced by the pandemic of coronavirus disease 2019(COVID-19),a disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Immunosuppressed individuals of liver transplant recipients(LTRs)tend to have a high risk of COVID-19 infection and related ***,COVID-19 vaccination has been recommended to be administered as early as possible in *** sources:The keywords“liver transplant”,“SARS-CoV-2”,and“vaccine”were used to retrieve articles published in ***:The antibody response following the 1st and 2nd doses of vaccination was disappointingly low,and the immune responses among LTRs remarkably improved after the 3rd or 4th dose of *** the 3rd or 4th dose of COVID-19 vaccine increased the antibody titer,a proportion of patients remained ***,recent studies showed that SARS-CoV-2 vaccine could trigger adverse events in LTRs,including allograft rejection and liver ***:This review provides the recently reported data on the antibody response of LTRs following various doses of vaccine,risk factors for poor serological response and adverse events after vaccination.

关键词： Liver transplant COVID-19 SARS-CoV-2 Vaccine Antibody response

Volatile metabolome and transcriptome reveal fragrance release rhythm and molecular mechanisms of Rosa yangii

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Journal of Integrative Agriculture 2023年第7期22卷 2111-2125页

作者： ZHOU Li-jun HUANG Run-huan liu Ting-han liu wei-chao CHEN Yun-yi LÜPei-feng LUO Le PAN Hui-tang YU chao ZHANG Qi-xiang Beijing Key Laboratory of Ornamental Plants Germplasm Innovation&Molecular Breeding/National Engineering Research Center for Floriculture/Beijing Laboratory of Urban and Rural Ecological Environment/Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education/School of Landscape Architecture Beijing Forestry UniversityBeijing 100083P.R.China

Rose is a highly significant ornamental plant with substantial edible and medicinal value,cultivated worldwide primarily for perfume ***,Rosa yangii,a new species found in northwestern Yunnan,China,has drawn attention due to its strong sweet scented *** this study,the floral components of *** were extracted at different flowering stages using solid phase micro extraction(SPME)and analyzed through gas chromatography-mass spectrometry(GC-MS).A total of 131 volatile organic compounds(VOCs)were detected from ***,including 69 odor *** production and release of floral VOCs were the highest during the initial-open stage,making it the most suitable time for harvesting as a significant number of floral components were synthesized and *** analysis of the odor activity values(OAV)highlighted several key aromatic ingredients of ***,such as eugenol,methyleugenol,benzeneacetaldehyde and phenylethylalcohol,heptanal,decanal,(E)-2-hexen-1-yl acetate,caryophyllene,and *** and time-order gene co-expression networks(TO-GCN)revealed that VOCs and benzenoids/phenylpropanoids,along with associated genes,played a pivotal role in the overall floral regulatory network of *** and bHLH were identified as the essential regulatory factors governing the regulation of eugenol synthase(EGS)and isoeugenol synthase(IGS),consequently influencing the sweet scent of *** findings of this study provide a scientific foundation for enhancing fragrance through molecular breeding of ornamental ***,the study facilitated the development and utilization of this new plant’s essential oil material in various industries,including food storage,aromatherapy,cosmetic,and perfumery.

关键词： rose sweet fragrance SPME-GC-MS aroma VOCs TO-GCN

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臭氧-超滤工艺用于城乡供水一体化工程

中国给水排水 2024年第14期40卷 131-136页

作者：刘伟超王龙占李培校韩永峰张银良郭兴郝俊升王笑飞许昌市建安区中州水务有限公司河南许昌461000 上海熊猫机械<集团>有限公司河南郑州450001 河南省水利勘测设计研究有限公司河南郑州450001

城乡供水水源采用地表水后,面临水源水质突变风险。某地区城乡供水一体化工程为提高供水的生物安全性和化学安全性,依据原水水质特征,选用臭氧-超滤组合处理工艺。介绍了该组合工艺的设计参数、设备选型及配置情况,并分析了实际运行效... 详细信息

城乡供水水源采用地表水后,面临水源水质突变风险。某地区城乡供水一体化工程为提高供水的生物安全性和化学安全性,依据原水水质特征,选用臭氧-超滤组合处理工艺。介绍了该组合工艺的设计参数、设备选型及配置情况,并分析了实际运行效果和运行成本。实践表明,臭氧-超滤组合工艺用于城乡供水一体化工程,能有效保障供水的生物安全性和化学安全性,并提升饮用水的供水品质。

关键词：城乡供水一体化工程南水北调臭氧氧化超滤耐氧化超滤膜

Wellbore-heat-transfer-model-based optimization and control for cooling downhole drilling fluid

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Petroleum Science 2024年第3期21卷 1955-1968页

作者： chao Wang He liu Guo-wei Yu Chen Yu Xian-Ming liu Peng Huang Yangtze University Jingzhou434023HubeiChina State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China CNPC Bohai Drilling Engineering Co. LtdTianjin300280China Exploration Development and Construction Engineering Division of PetroChina Jidong Oilfield Company Tangshan63200HebeiChin Henan University of Urban Construction Pingdingshan467036HenanChina

To address the two critical issues of evaluating the necessity of implementing cooling techniques and achieving real-time temperature control of drilling fluids underground in the current drilling fluid cooling technology,we first established a temperature and pressure coupled downhole heat transfer model,which can be used in both water-based and oil-based drilling ***,fourteen factors,which could affect wellbore temperature,were *** on the standard deviation of the downhole temperature corresponding to each influencing factor,the influence of each factor was *** influencing factors that can be used to guide the drilling fluid's cooling technology were drilling fluid thermal conductivity,drilling fluid heat capacity,drilling fluid density,drill strings rotation speed,pump rate,viscosity,ROP,and injection *** nondominated sorting genetic algorithm was used to optimize these six parameters,but the optimization process took 182 *** these eight parameters'influence rules with the nondominated sorting genetic algorithm can reduce the optimization time to 108 ***,the downhole temperature has been demonstrated to increase with the inlet temperature increasing linearly under quasi-steady *** this law and PID,the downhole temperature can be controlled,which can reduce the energy for cooling the surface drilling fluid and can ensure the downhole temperature reaches the set value as soon as possible.

关键词： Drilling Cooling Influencing factors Analysis Optimization Control

Dynamical switchable quantum nonreciprocity induced by off-resonant chiral two-photon driving

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 31-37页

作者： Da-wei liu Zi-Hao Li Shi-Lei chao Ying Wu liu-Gang Si School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Optical nonreciprocity,which refers to the direction-dependent emission,scattering and absorption of photons,plays a very important role in quantum engineering and quantum information ***,we propose an all-optical approach to achieve the optical dynamical switchable quantum nonreciprocity by an off-resonant chiral two-photon driving in a single microring cavity,which differs from the conventional nonreciprocal *** is shown that the optical field with time-dependent statistical properties can be generated and the nonreciprocity flips periodically,with switchable photon blockade and photon-induced tunneling *** find that the dynamical system is robust and immune to the parameter variations,which loosens the parameter range of ***,the time window for one-way quantum information is sufficiently wide and *** work opens a new idea for the current quantum nonreciprocal research,which can facilitate a memory functionality and be used for future inmemory superconducting quantum *** other nonreciprocal quantum devices,i.e.,dynamical switchable nonreciprocal squeezing and entanglement,may be inspired by our method,which is expected to have important applications in future quantum technology.

关键词： dynamical switchable nonreciprocity single-photon source chiral two-photon driving

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Unraveling the hydraulic properties of loess for landslide prediction:A study on variations in loess landslides in Lanzhou,Dingxi,and Tianshui,China

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China Geology 2024年第2期7卷 291-302页

作者： Gao-chao Lin wei liu Xing Su School of Civil and Environmental Engineering University of New South WalesSydneyNSW 2052Australia Institute of Transportation Inner Mongolia UniversityHohhot 010070China Institute of Geological Hazards Prevention Gansu Academy of SciencesLanzhou 730000China

Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re *** involvement of water repre sents a critical factor in inducing loess *** study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide *** variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity *** experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention ***,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest *** results are supported and analyzed by scanning electron microscopy(SEM)*** addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of *** experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters.

关键词： Loess Landslide Hydraulic properties Water retention capacity and permeability Soil Water Characteristic Curve(SWCC) Hydraulic conductivity Van Genuchten model Hydrogeological engineering Geological hazards prevention engineering

Highly Porous Yet Transparent Mechanically Flexible Aerogels Realizing Solar-Thermal Regulatory Cooling

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Nano-Micro Letters 2024年第7期16卷 231-243页

作者： Meng Lian wei Ding Song liu Yufeng Wang Tianyi Zhu Yue-EMiao chao Zhang Tianxi liu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620People’s Republic of China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122People’s Republic of China

The demand for highly porous yet transparent aerogels with mechanical flexibility and solar-thermal dual-regulation for energy-saving windows is significant but ***,a delaminated aerogel film(DAF)is fabricated through filtration-induced delaminated gelation and ambient *** delaminated gelation process involves the assembly of fluorinated cellulose nanofiber(FCNF)at the solid-liquid interface between the filter and the filtrate during filtration,resulting in the formation of lamellar FCNF hydrogels with strong intra-plane and weak interlayer hydrogen *** exchanging the solvents from water to hexane,the hydrogen bonding in the FCNF hydrogel is further enhanced,enabling the formation of the DAF with intra-layer mesopores upon ambient *** resulting aerogel film is lightweight and ultra-flexible,which pos-sesses desirable properties of high visible-light transmittance(91.0%),low thermal conductivity(33 mW m^(-1) K^(-1)),and high atmospheric-window emissivity(90.1%).Furthermore,the DAF exhibits reduced surface energy and exceptional hydrophobicity due to the presence of fluorine-containing groups,enhancing its durability and UV ***,the DAF has demonstrated its potential as solar-thermal regulatory cooling window materials capable of simultaneously providing indoor lighting,thermal insulation,and daytime radiative cooling under direct ***,the enclosed space protected by the DAF exhibits a temperature reduction of 2.6℃ compared to that shielded by conventional architectural glass.

关键词： Transparent aerogel Cellulose nanofiber aerogel Delaminated gelation Thermal insulation Passive daytime radiative cooling

彭江云教授运用桂枝汤类方辨治成人Still病经验

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风湿病与关节炎 2024年第2期13卷 33-35页

作者：孟凡雨刘维超殷建美张昊喆晏蔚田彭江云(指导) 云南中医药大学云南昆明650000 云南中医药大学第一附属医院云南昆明650021

云南省名中医彭江云教授结合多年风湿病诊疗经验,认为成人Still病发病的核心病机在于营卫失调,指出治疗上应以调和营卫为主,临床常用桂枝汤类方辨治。根据病程之长短辨证使用玉屏风桂枝汤、柴葛桂枝汤、补中桂枝汤,并根据主证酌情加减用... 详细信息

云南省名中医彭江云教授结合多年风湿病诊疗经验,认为成人Still病发病的核心病机在于营卫失调,指出治疗上应以调和营卫为主,临床常用桂枝汤类方辨治。根据病程之长短辨证使用玉屏风桂枝汤、柴葛桂枝汤、补中桂枝汤,并根据主证酌情加减用药,临床取得了良好疗效。

关键词：成人Still病桂枝汤类方营卫经验彭江云