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NONLINEAR DYNAMICS RESPONSE OF CASING PIPE UNDER COMBINED WAVE-CURRENT

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Applied Mathematics and Mechanics(English Edition) 2005年第8期26卷 1040-1046页

作者： TANG You-gang（唐友刚） gu Jia-yang（谷家扬） ZUO Jian-li（左建立） MIN Jian-qin（闵建琴） Department of Naval Architecture and Ocean Engineering School of Civil Engineering Tianjin University Tianiin 300072. P. R. China

The vortex-induced nonlinear vibration of casing pipes in the deep water was studied considering the loads of current and combined wave-current. The vortex-induced vibration equation of a casing pipe was set up considering the beam mode and Morison＇s nonlinear fluid loads as well as the vortex-excited loads. The approach of calculating vortex-excited nonlinear vibration by Galerkin＇s method was proposed. The natural vibration frequencies and modes were obtained, and the response including primary resonance induced by current and the composite resonance under combined wave-current for the 170 m long casing pipe in the 160 m depth of water were investigated. The results show that the dynamics response of casing pipe obviously increases, and the complicated response behaviors of casing pipe are described under combined wavecurrent.

关键词： casing pipes in the deep water fluid dynamics combined wave-current vortex-excited vibration composite resonance

Composition of algal pigments in surface freshen layer after ice melt in the central Arctic

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Acta Oceanologica Sinica 2017年第8期36卷 122-130页

作者： ZHUANG Yanpei JIN Haiyan gu Fan ZHANG Yang BAI Youcheng JI Zhongqiang LU Yong CHEN lianfang Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of OceanographyState Oceanic AdministrationHangzhou 310012China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic AdministrationHangzhou 310012China

Seasonal meltwater input creates a thin freshen layer in surface seawater under ice, which largely shifts the algae assemblages. Our recent observation of photosynthetic pigments in the high Arctic showed that ice bottom and 5 m of seawater under ice contained relatively high concentration of fucoxanthin, while chlorophyll b and lutein were the major diagnostic pigments in ice-water interface and 0 m of seawater under ice. Additionally, a notable change of dominant phytoplankton occurred in the top 5 m of seawater under ice, from chlorophytes-dominated at surface to diatoms-dominated at 5 m depth, which might attribute to the sharp salinity gradient （salinity from 12.5 to 28.1） in the surface seawater under ice. Our results imply that phytoplankton community in surface layer under ice would become more chlorophytes in the future warming Arctic Ocean.

关键词： the Arctic Ocean seawater under ice pigments nutrients phytoplankton community

Composite topological nodal lines penetrating the Brillouin zone in orthorhombic AgF_(2)

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npj Computational Materials 2019年第1期5卷 694-701页

作者： Dexi Shao Huaiqiang Wang Tong Chen Pengchao Lu Qinyan gu Li Sheng Dingyu Xing Jian Sun National Laboratory of Solid State Microstructures and Department of Physics Nanjing University210093 NanjingChina Collaborative Innovation Center of Advanced Microstructures 210093 NanjingChina

It has recently been found that nonsymmorphic symmetries can bring many exotic band ***,based on symmetry analysis,we predict that materials with time-reversal symmetry in the space group of Pbca(No.61)possess rich symmetry-enforced band crossings,including nodal surfaces,fourfold degenerate nodal lines and hourglass Dirac loops,which appear in triplets as ensured by the cyclic permutation *** take Pbca AgF_(2) as an example in real systems and studied its band structures with ab initio ***,in the absence of spin-orbit coupling(SOC),besides the above-mentioned band degeneracies,this system features a nodal chain and a nodal armillary sphere penetrating the Brillouin zone(BZ).While with SOC,we find a new configuration of the hourglass Dirac loop/chain with the feature traversing the BZ,which originates from the splitting of a Dirac loop confined in the ***,guided by the bulk-surface correspondence,we calculated the surface states to explore these bulk nodal *** evolution of these interesting nodal phenomena traversing the BZ under two specific uniaxial strains is also discussed.

关键词： nodal symmetry Brillouin

Flow patterns and critical criteria of thermally stratified shear flow in braided rivers

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Water Science and Engineering 2017年第3期10卷 225-235页

作者： Li gu Qiu-lan Li Bo Dai Zu-lin Hua Xiao-dong Liu Ke-jian Chu Department of Civil and Environmental Engineering University of AlbertaEdmonton T6G 2R3Canada Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes Ministry of EducationHohai UniversityNanjing 210098China Zhenjiang Urban Planning and Design Institute Zhenjiang 212000China Jiangsu Transportation Institute Nanjing 210098China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai UniversityNanjing 210098China

Flow characteristics of thermally stratified shear flow in braided rivers are particularly complicated and poorly understood. In this study, a series of typical flow patterns was examined and their critical criteria were determined. Four flow patterns were identified: mixed, locally unstable, continuously stratified, and two-layer flow. Temperature distributions of the four types of flow patterns were analyzed and *** critical Froude numbers for unstable flow, FDcr1, and stable flow, FDcr2, were determined to be 6 and 1, respectively, and comparison of FDcr1 and FDcr2 to the peak Froude numbers, FD1 at the outer bank and FD2 at the inner bank along the anabranch, allowed the flow patterns to be assessed. Then, a discriminant based on initial Jeffreys-Keulegan stability parameters was established to distinguish the flow stages from twolayer flow to completely mixed flow. It is indicated that the three critical Jeffreys-Keulegan parameters increased with the diversion angle of braided rivers. Results also show that, compared to the stratified flow in straight and curved channels, it was more difficult for braided stratified flow to maintain as two-layer flow, and it more easily became mixed flow. Consequently, empirical expressions for stability criteria of the thermally stratified shear flow in braided rivers are presented.

关键词： Braided river Critical criterion Empirical formula Flow pattern Temperature distribution Thermally stratified flow

CO_(2) combining power and outcomes in patients with acute ischaemic stroke or transient ischaemic attack

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Stroke & Vascular Neurology 2021年第2期6卷 252-259页

作者： Anxin Wang Xue Tian Hongqiu gu Yingting Zuo Xia Meng Wei Lv Hao Li Yongjun Wang China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Epidemiology and Health Statistics School of Public HealthCapital Medical UniversityBeijingChina Beijing Municipal Key Laboratory of Clinical Epidemiology BeijingChina

Background and purpose The clinical significance of carbon dioxide combining power(CO_(2) CP)in ischaemic cerebrovascular disease is not well established,and the role of CO_(2) CP in the prognosis of acute ischaemic stroke(AIS)or transient ischaemic attack(TIA)has not been *** objective of the study was to investigate the associations between CO2CP and clinical outcomes in patients with AIS or *** Data were derived from the China National Stroke Registry *** were classified into five groups by quintiles of CO_(2) CP levels and three groups according to the normal range of CO_(2)CP(23-29 mmol/L).Multivariable Cox and logistic regressions were adopted to explore the associations of CO_(2) CP levels with all-cause death and poor functional outcomes(modified Rankin Scale(mRS)3-6/2-6)at 3 months and 1 *** Among 9531 patients included in the study,the median(IQR)CO_(2) CP was 24.9(23.0-27.0)mmol/*** adjustment for potential confounders,patients in the first CO_(2) CP quintile(21.1-23.3 mmol/L)had higher risk of all-cause death and poor functional outcomes(mRS score of 3-6/2-6)(HR or OR with 95% CI 2.37(1.32 to 4.25),1.49(1.20 to 1.83)and 1.21(1.03 to 1.42),respectively)compared with those in the fourth *** results were found for outcomes at 1 ***,all associations were also significant when CO_(2) CP was<23 mmol/L compared with CO_(2) CP of 23-29 mmol/*** Decreased CO_(2) CP was associated with high risk of all-cause death and poor functional outcomes in patients with AIS or TIA.

关键词： patients ischaemic acute

认知症患者照顾者赋能与家庭抗逆力的纵向研究

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护理学杂志 2025年第2期40卷 80-84页

作者：顾清昕陈玲玲陈美倩周倩如李婷崔金鑫张立秀湖州师范学院医学院护理学院浙江湖州313000 慈溪职业高级中学

目的探究认知症患者照顾者赋能与家庭抗逆力的发展轨迹及两者的相互预测关系,为提高家庭抗逆力提供依据。方法2023年6月至2024年7月,采用便利抽样法选择湖州市19个社区的239名认知症患者照顾者为研究对象,采用一般资料调查表、认知症患... 详细信息

目的探究认知症患者照顾者赋能与家庭抗逆力的发展轨迹及两者的相互预测关系,为提高家庭抗逆力提供依据。方法2023年6月至2024年7月,采用便利抽样法选择湖州市19个社区的239名认知症患者照顾者为研究对象,采用一般资料调查表、认知症患者照顾者赋能量表、中文版家庭抗逆力量表进行3次追踪调查,每次间隔6个月,通过平行发展模式的潜变量增长模型和交叉滞后模型进行数据分析。结果认知症患者照顾者赋能[斜率(S=0.401,P=0.021)]和家庭抗逆力(S=1.457,P=0.007)随时间推移呈线性上升趋势,照顾者赋能的初始水平能正向预测家庭抗逆力的初始水平(β=0.492,P<0.001)和发展速度(β=0.719,P<0.001),3次调查中上一时间点的照顾者赋能均能正向预测下一时间点的家庭抗逆力(β=0.496,P<0.001;β=0.230,P<0.001)。结论认知症患者照顾者赋能和家庭抗逆力随着时间的推移逐渐增强,照顾者赋能是家庭抗逆力发展过程中的促进因素。建议医护人员通过多元途径促进认知症患者照顾者赋能,提升其家庭抗逆力。

关键词：认知症痴呆失智症照顾者赋能家庭抗逆力潜变量增长模型交叉滞后模型

Optimization of Calcium Addition to High-strength Low-alloy Steels

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Journal of Iron and Steel Research International 2015年第7期22卷 590-597页

作者： gu-jun CHEN Sheng-ping HE Yin-tao guO Bo-yi SHEN Shuo ZHAO Qian WANG College of Materials Science and Engineering Chongqing University

Nozzle blockage is a common problem during continuous casting of Al-killed steel, and calcium treatment is widely used to resolve it. In consideration of the production costs, the technology of nonmetallic inclusion control was studied to optimize the Ca consumption. The proposed process of slag washing was employed, and the refining slag composition, deoxidation conditions and alloying systems were optimized. Using these measures, the steel cleanliness before Ca addition was improved significantly, and the corresponding Ca consumption was reduced. More- over, the continuous casting could be conducted smoothly.

关键词： nozzle blockage high-strength low-alloy steel calcium treatment slag washing steel cleanliness

Convenient synthesis of aryl-incorporated ditosylates and their application in preparation of crown ethers with higher yield

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Chinese Chemical Letters 2008年第8期19卷 911-914页

作者： Oi Zhong Zhou Chun Lin He Hai Ning gu Qi Ming Miao Chun Xi Zhai Department of Chemistry Zhejiang University Hangzhou 310027 China

A convenient synthetic method with high yields for aryl-incorporated ditosylates by reaction of aryl-incorporated diols with TsCI in THF/NaOH/H2O solution was described. Some of these aryl-incorporated ditosylates rea... 详细信息

关键词： Aryl-incorporated diol Ditosylate Crown ether

NIR Light-Promoted Whole-Cell Catalysis Based on a Light-Harvesting Blackbody Bioreactor

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Journal of Analysis and Testing 2023年第3期7卷 237-244页

作者： Jinhui gu Qisi Li Mengting Cao Xiaojia Zhang Xinpei Ding Haiyan Chen Nan Wang Zhijun Zhang Key Laboratory of Surface and Interface Science of Polymer Materials of Zhejiang Province School of Chemistry and Chemical EngineeringZhejiang Sci-Tech UniversityHangzhou 310018China Shaoxing Keqiao Research Institute of Zhejiang Sci-Tech University Shaoxing 312000China Shengzhou Innovation Research Institute of Zhejiang Sci-Tech University Shengzhou 312400China

Whole-cell catalysis,which utilizes enzymes expressed in whole organism(*** and fungi)as the catalyst,is a specific mode of *** with pure enzyme catalysis,the catalysis with whole-cell catalysts is more ***,in the process of whole-cell catalysis,heat treatment is often necessary due to the high optimum temperature of the *** enable efficient industrial application of whole-cell catalysis,an environmental friendly heating approach is highly *** by the light harvest by blackbody materials,in this paper,we introduced a photothermal approach for harnessing the photon energy for enhanced whole-cell catalysis.A blackbody porous sponge(BPS)with excellent photothermal conversion efficiency was prepared as a *** coli expressed with a thermophilic enzyme(β-glucosidase)was utilized as a model whole-cell ***,the photothermal properties of the BPS and lightassisted whole-cell catalysis were systematically investigated,demonstrating promising application prospects.

关键词： Whole-cell catalysis Biocatalysis Photothermal eff ect Near-infrared light response Blackbody materials Porous sponge