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Investigation of wake-induced vibration interference between two staggered wave-cone cylinders at subcritical Reynolds number

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Journal of Hydrodynamics 2024年第2期36卷 378-393页

作者： Lin Zou di-wei Liu Jian Liu Hong-cheng Zuo Yin-huan.Zheng Hao Xia School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan430070China Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughboroughUK

The wake induced vibration(WIV)of a one-and two-degree-of-freedom(1DOF,2DOF)downstream wave-cone cylinder(WCC)behind a stationary equal-size upstream wave-cone cylinder in the staggered arrangement is numerically investigated at subcritical Reynolds number of 3900 by using shear stressed transfer(SST)k-ωturbulence *** streamwise pitch ratios(P/Dm)vary from 4 to 6 with a fixed incident angleα=8°.Experimental measurements were also performed for the validation of the present numerical *** is found that the largest vibration amplitude in crossflow direction occurred at P/Dm=4,Ur=8 with small difference of streamwise vibration at P/Dm=4,*** from single wavy-cone cylinder(SWCC),the downstream flexible one of a pair staggered WCCs got larger vibration amplitude during phase switching stage instead of in-phase *** upstream wake will suppress the triple frequency of main frequency in the power spectra density(PSD)functions of Cl but stimulate the double one of *** intriguing vibration mechanism happened in all 2DOF cases where the trajectory of downstream WCC is a significant ellipse rather than a figure of *** transformation of phase switching and the variation of the main frequency of drag coefficient(Cd)can be explained by the vortex-shedding modes of downstream WCC.

关键词： Two wave-cone cylinders staggered arrangement wake induced vibration phase switching vortex shedding

Linear Viscoelasticity of ABA-type Vitrimer Based on dioxaborolane Metathesis

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Chinese Journal of Polymer Science 2024年第10期42卷 1495-1504,I0010页

作者： Shi-Long Wu huan.huan.Yang Quan Chen State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of ScienceChangchun130022China University of Science and Technology of China Hefei230026China

In this study,we synthesized a series of ABA-type vitrimers by crosslinking the short A moieties of precursors with a bifunctional crosslinker and evaporating the small molecular *** vitrimer samples thus prepared exhibit linear viscoelasticity dependent on the length of A moiety as well as the content of the *** the average number of A monomers per end moiety m=1.1,the crosslinker can only extend the chain but not crosslink the *** m becomes 2.8 or higher,introducing a crosslinker first leads to the gelation,whereas excess in crosslinker molecules leads opening of the crosslinking sites and accordingly reentry into the sol ***,a further increase in the length of the A moieties increases the relaxation time much weaker than the exponential increase seen for the physically crosslinked ABAtype *** attribute this difference to the distinct relaxation mechanisms:the relaxation of the vitrimer samples is based on relatively independent exchange reactions,which contrasts with the ABA-type ionomers that relax through the collective hopping of connected ionic groups from one ion aggregate to another.

关键词： Polymer rheology Linear viscoelasticity ABA-type vitrimer Relaxation mechanism Kinetics and thermodynamics

The Coarse l^(p)-Novikov Conjecture and Banach Spaces with Property(H)

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 193-220页

作者： huan.WANG Qin WANG Research Center for Operator Algebras School of Mathematical SciencesEast China Normal UniversityShanghai 200241China Key Laboratory of MEA Ministry of Educationand Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China

In this paper,for 1

关键词： The coarse l^(p)-Novikov conjecture Banach spaces with Property(H) Coarse geometry K-Theory

An efficient approach for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic excitations

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 677-690页

作者： huan. huan.Li Yingxiong Li Yuyu College of Water Conservancy and Civil Engineering South China Agricultural UniversityGuangzhou 510642China Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 611756China

An efficient approach is proposed for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic *** concentrated plastic hinges,described by the Bouc-Wen model,are assumed to occur at the two ends of a linear-elastic beam *** auxiliary differential equations governing the plastic rotational displacements and their corresponding hysteretic displacements are replaced with linearized differential ***,the two sets of equations of motion for the original nonlinear system can be reduced to an expanded-order equivalent linearized equation of motion for equivalent linear *** solve the equation of motion for equivalent linear systems,the nonstationary random vibration analysis is carried out based on the explicit time-domain method with high ***,the proposed treatment method for initial values of equivalent parameters is investigated in conjunction with parallel computing technology,which provides a new way of obtaining the equivalent linear systems at different time *** on the explicit time-domain method,the key responses of interest of the converged equivalent linear system can be calculated through dimension reduction analysis with high *** examples indicate that the proposed approach has high computational efficiency,and shows good applicability to weak nonlinear and medium-intensity nonlinear systems.

关键词： nonstationary random vibration plastic hinge equivalent linearization method explicit time-domain method parallel computation

Numerical investigation on dynamic response of the screen mesh in vibrating screening through DEM-FEM co-simulation

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Particuology 2024年第4期87卷 205-217页

作者： huan.Zhang Xiao Zheng Weimin Jing Key Laboratory of MetallurgicalEquipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081 China Hubei Key Laboratory of Mechanical Transmssion and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400044China

Dynamic response of the screen mesh is of great significance in the optimum vibrating screen *** this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle ***,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen ***,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the ***,the influence of screening parameters on LVA and its distribution was *** results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.

关键词： Vibrating screen Dynamic response DEM-FEM Screening parameters Local vibration amplitude

Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo Dong huan.Lu Hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

Jianpi Decoction Combined with Medroxyprogesterone Acetate Alleviates Cancer Cachexia and Prevents Muscle Atrophy by directly Inhibiting E3 Ubiquitin Ligase

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Chinese Journal of Integrative Medicine 2024年第6期30卷 499-506页

作者： LI Qi KONG Zhao-di WANG huan.GU Hong-hui CHEN Zhong Li Shi-guang CHEN Yi-qi CAI Yu YANG Zhen-jiang Department of Oncology and Hematology Shenzhen Traditional Chinese Medicine HospitalShenzhenGuangdong Province518033China College of Pharmacy/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education(MOE)of China Jinan UniversityGuangzhou510632China Guangdong Key Lab of Traditional Chinese Medicine Information Technology Jinan UniversityGuangzhou510632China

ObjectiveTo provide comprehensive evidence for the anti-cancer cachexia effect of Jianpi Decoction(JP)and to explore its mechanism of anti-cancer *** mouse model of colon cancer(CT26)-induced cancer cachexia(CC)was used to investigate the anti-CC effect of JP combined with medroxyprogesterone acetate(MPA).Thirty-six mice were equally divided into 6 groups:normal control,CC,MPA(100 mg·kg^(−1)·d^(−1)),MPA+low-dose(20 mg·kg^(−1)·d^(−1))JP(L-JP),MPA+medium-dose(30 mg·kg^(−1)·d^(−1))JP(M-JP),and MPA+high-dose(40 mg·kg^(−1)·d^(−1))JP(H-JP)*** successful modeling,the mice were administered by gavage for 11 *** body weight and tumor volume were measured and recorded every 2 d starting on the 8th day after *** liver,heart,spleen,lung,kidney,tumor and gastrocnemius muscle of mice were collected and *** pathological changes of the tumor was observed,and the cross-sectional area of the gastrocnemius muscle was *** protein expressions of STAT3 and E3 ubiquitinase in the gastrocnemius muscle were measured by Western *** addition,an in vitro C2C12 myotube formation model was established to investigate the role of JP in hindering dexamethasone-induced muscle *** vitro experiments were divided into control,model,and JP serum *** 2-d administration,microscopic photographs were taken and myotube diameters were *** blot was performed to measure the protein expressions of STAT3 and E3 *** combined with MPA restored tumor-induced weight loss(Pdition,JP reduced the expression of atrophy-related proteins MuRF1 and MAFbx and p-STAT3 phosphorylation(P<0.05 or P<0.01 *** group)in C2C12 myotubes treated with dexamethasone in *** of JP combined with MPA restores t

关键词： cancer cachexia muscle atrophy Jianpi Decoction Chinese medicine E3 ubiquitin ligases

Aberrant protamination in sperm correlates to anomalous nuclear and cytoplasmic architectures in infertile males with sperm dysmorphology

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Asian Journal of Andrology 2024年第2期26卷 183-188页

作者： huan.Jiang Chu-Jie huan. Department of Reproductive Endocrinology Longgang District Maternity&Child Healthcare Hospital of Shenzhen City(Longgang Maternity and Child Institute of Shantou University Medical College)Shenzhen 518172China Institute of Reproductive Immunology College of Life Science and TechnologyJinan UniversityGuangzhou 510632China

Aberrant sperm protamination is linked to sperm dysmorphology and nuclear chromatin ***,its effects on sperm cytoplasmic maturation remain largely *** relationships of protamines,sperm morphology,DNA damage,and cytoplasmic remodeling were illustrated in this study to provide fresh perspectives on the mechanisms of male infertility.A total of 205 infertile males were allocated into 5 groups according to the percentage of spermatozoa exhibiting abnormal morphology within their *** concentration,motility,abnormal sperm morphology,cytoplasmic droplets(CDs),and excess residual cytoplasm(ERC)were analyzed according to the World Health Organization manual(2010).Sperm nuclear vacuoles(NVs)were determined by propidium iodide(PI)*** protamine expressions(P1 and P2)were detected by western *** damage was measured by acridine orange test(AOT)to calculate the proportion of sperm with single-strand DNA breaks(SSBs).Our data showed that sperm concentration and motility in infertile males significantly decreased with the severity of abnormal sperm morphology(both Pdicator of sperm quality and male fertility.

关键词： abnormal sperm morphology excess residual cytoplasm male infertility protamines sperm DNA damage sperm nuclear vacuoles

Low profile cavity-embedded ultra-wideband UHF array antenna with end-fire beams

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Journal of Electronic Science and Technology 2024年第2期22卷 24-35页

作者： huan.He Wen-Song Wang Southwest China Institute of Electronic Technology Chengdu610036China School of Electrical and Electronic Engineering Department Nanyang Technological UniversitySingapore639798Singapore

A low-profile,vertically polarized,ultra-wideband array antenna with end-fire beams operating in an ultra-high frequency(UHF)band is developed in this *** array antenna consists of 1×16 log-periodic top-hat loaded monopole antenna arrays and is feasible to embed into a shallow cavity to further reduce the array *** is introduced in the proposed antenna element to reduce profile height and the rectangular top hats are carefully designed to minimize the transverse *** results show that when the antenna array operates in a frequency range of 300 MHz-900 MHz,the end-fire radiation pattern achieves±45°scanning range in the horizontal *** prototypes of the proposed end-fire antenna element and a uniformly spaced linear array(1×2)are fabricated and *** end-fire antenna array should be suitable for airborne applications where low-profile and conformal scanning phased antenna arrays with end-fire radiations are *** design is attractive for airborne platform applications that are used to search,discover,identify,and scout the aerial target with vertically polarized beams.

关键词： End-fire radiation Low-profile Vertical polarization Log-periodic array