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Effect of microalloying on wettability and interface characteristics of Zr-based bulk metallic glasses with W substrate

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China Foundry 2024年第4期21卷 352-359页

作者： Zhen Zhang lin-na Feng Jin-he Wang {1.-kun Li Hua-meng Fu Hong Li {1.-wang Zhu Hai-feng Zhang School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Northeastern UniversityShenyang 110004China

The infiltration casting method is widely employed for the preparation of ex-situ composite ***,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming *** experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs ***,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

关键词： Zr-based BMGs infiltration casting method wettability interface characteristics W-Zr phases

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 {1. 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(1.OF,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

Divergent changes in diversity and network complexity across different trophic-level organisms drive soil multifunctionality of fire-impacted subtropical forests

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Forest Ecosystems 2024年第5期11卷 697-707页

作者： Luhong Zhou Shangshi Liu Debao lin Hang-Wei Hu Ji-{1. He Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education School of Geographical SciencesFujian Normal UniversityFuzhou350007China Department of Earth and Environmental Sciences University of ManchesterOxford RoadManchesterM139PTUK School of Agriculture Food and Ecosystem SciencesFaculty of ScienceThe University of MelbourneParkville3010Australia

Widespread forest fires pose significant challenges to the diverse communities of soil-dwelling organisms and the multiple ecosystem functions they ***,whether the biodiversity and interactions of various taxonomic groups respond to fire consistently in terms of direction and extent,and their relative role in regulating post-fire soil functioning,remains largely *** this study,we investigated whether the diversity and co-occurrence networks of soil organisms across various trophic levels(including bacteria,fungi,protists,and invertebrates)in subtropical forests exhibit consistent responses to ***,we investigated their contribution to regulating soil multifunctionality,which is measured by a range of soil extracellular enzyme activities,available nutrients and reduced potential fungal plant *** findings revealed that fire led to a decline in the richness of fungi,protists,and invertebrates,without significantly impacting bacterial *** also simplified the microbial co-occurrence networks while complexifying the invertebrate ***,soil multifunctionality tended to decrease with the richness of lower-trophic communities(i.e.,bacteria),whereas it increased with that of high-trophic communities(i.e.,protists and invertebrates).Moreover,fire indirectly influenced soil multifunctionality by altering biodiversity and network complexity,particularly pronounced in high-trophic ***,our results underscored the divergent vulnerability of biodiversity and networks to fires across taxa groups,highlighting the crucial role of biodiversity and interactions of higher trophic taxa groups in shaping the recovery and functionality of fire-affected soils.

关键词： Invertebrates Microorganism Multifunctionality Protists Wildfire

Optimization and experimental analysis of sweet potato ship-shaped transplanting trajectory using particle swarm algorithm

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 100-107页

作者： zhengduo Liu {1. Hua Zhaoqin Lyu Jiaji Hu Wenxiu zheng College of Mechanical and Vehicle Engineering West Anhui UniversityLu’an 237000AnhuiChina Traditional Chinese Medicine Institute of Anhui Dabie Mountain West Anhui UniversityLu’an 237012AnhuiChina College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018ShandongChina Anhui zhengyang Machinery Technology Co. Ltd.Lu’an 237012AnhuiChina

The mechanization of ship-shaped transplanting is currently an urgent problem that should be *** movement trajectory of the transplanting mechanism is the key technology to perform ship-shaped *** this study,a ship-shaped transplanting trajectory was built and a mathematical model of a four-link transplanting mechanism was developed based on the requirements of the sweet potato transplanting agronomic *** particle swarm optimization algorithm was used,with the length of the four-bar mechanism and the installation angle of the fixed bar serving as the variables to *** objective was to minimize the deviation of the ship-shaped transplanting trajectory,yielding an iterative optimization *** MATLAB simulation results showed that the penalty factors of different proportions in the adaptive particle swarm optimization algorithm affected the transplanting *** optimal penalty factor parameters areα=0.6,β=*** ensure that the transplanting trajectory fulfills the agronomic requirements,and limit the deviation in the return trajectory of the *** sizes of the optimized four-bar mechanism were 1.0,31.,245,1.0,360,and,1.0 *** determined installation angle was 1.0°.The results of the field experiments demonstrated that the optimized four-bar transplanting mechanism can better fulfill the agronomic technical requirements of sweet potato ship-shaped *** a transplanting speed of 0.2 m/s,the average qualified rates of insertion depth,insertion length,and tail height were equal to 94.00%,93.83%,and 91.67%.The results obtained in this study provide a theoretical basis and technical support for studying and developing sweet potato ship-shaped transplanting machinery.

关键词： sweet potato oblique insertion method mechanical arm particle swarm

Effect of Small Needle Knife on Autophagy and TGF-β in Synovial Fluid of KOA Rats

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Chinese Journal of Biomedical Engineering(English Edition) 2024年第1期33卷 33-39页

作者： zheng Kang-hua {1. Zeng-ping CHEN Yong Fujian Provincial 2nd People's Hospital Affiliated Hospital of Fujian University of Traditional Chinese MedicineFuzhou Fujian 350003China College of Integrative Chinese and Western Medicine Fujian University of Traditional Chinese MedicineFuzhou Fujian 350122China

Objective:To explore the effects of small needle knife on the autophagy function of synovium and the expression of TGF-βin synovial fluid of KOA rats,so as to provide a new theoretical basis for the treatment of ***:48 SD rats were randomly divided into blank control group,model group,drug group and acupotomy *** blank control group maintained the original feeding without any intervention,the model group adopted the sodium monoiodoacetate injection method to prepare the KOA rat model without any intervention,the drug group prepared the KOA rat model and then treated with tripterine by gavage,and the needle knife group treated the KOA rat model with small needle *** expression levels of autophagy-related proteins in synovial tissues were detected by immunohistochemistry and Western blotting,and the content of TGF-βin synovial fluid was measured by ***:Compared with the blank control group,Beclin-1.Caspase-3 and Bax were up-regulated and m TOR was down-regulated in the model ***-1.m TOR,Caspase-3 and Bax were up-regulated in the drug *** was no significant difference in the expression of autophagy-related proteins Beclin-1.0.28±0.09)and m TOR(0.45±0.1.)between the acupotomy group and the blank control group,while Caspase-3(0.1.±0.03)and Bax(0.30±0.01.were *** expression level of TGF-βin synovial fluid in the small needle knife group was(0.29±0.09),which was similar to that in the blank control group,and was significantly higher than that in the model ***:Small needle knife treatment can promote the recovery of synovial autophagy in KOA rats,and reduce the level of TGF-βin synovial fluid,and can play a clinical role in the treatment of KOA by regulating the expression of synovial autophagy and TGF-β.

关键词： small needle knife knee osteoarthritis(KOA) synovium autophagy transforming growth factorβ(TGF-β)

Normal sperm head morphometric reference values in fertile Asian males

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Asian Journal of Andrology 2024年第3期26卷 315-320页

作者： Ye-lin Jia Ying-Bi Wu lin Yu Yan zheng Ting-Ting Yang Yan-Yun Wang Bin Zhou lin Zhang Fu-Ping Li Laboratory of Andrology West China Second University Hospital Human Sperm BankChengdu 610000China Laboratory of Molecular Translational Medicine Center for Translational MedicineChengdu 610061China Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationChengdu 610061China NHC Key Laboratory of Chronobiology West China Second University HospitalSichuan UniversityChengdu 610000China

Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive *** are available to analyze sperm head morphology,but they are limited by poor methodology comparability and *** study aimed to explore comprehensive and new normal morphometric reference values for spermatozoa heads infertile Asian *** automated sperm morphology analysis system captured 231.2 stained spermatozoa from confirmed *** these samples,1.56 sperm head images were annotated by three experienced laboratory technicians as“normal”.Weemployed 1. novel morphometric features to describe sperm head size(head length,head width,length/width ratio,and girth),shape(ellipse intersection over union,girth intersection over union,short-axis symmetry,and long-axis symmetry),area(head,acrosome,postacrosomal areas,and acrosome area ratio),and degrees of acrosome and nuclear *** straight-forwardmethod for the morphometric analysis of sperm by accurate visual measurements is clinically *** measured parameterspresent valuable information to establish morphometric reference intervals for normal sperm heads in fertile Asian *** detailed measurement data will be valuable for interlaboratory comparisons and technician *** vitro fertilizationand andrology laboratory technicians can use these parameters to perform objective morphology evaluation when assessing malefertilization potential.

关键词： fertile Asian males head morphometric reference value normal spermatozoa

Relationship between dietary niacin intake and erectile dysfunction:a population-based study

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Asian Journal of Andrology 2024年第4期26卷 382-388页

作者： Wei-Long lin Cheng {1. Hao-Xu Wang Wei Zhang Ming-En lin Department of Urology The First Affiliated Hospital of Shantou University Medical CollegeMedical College of Shantou UniversityShantou 515041China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou 510260China.

Existing research on the precise link between dietary niacin intake and erectile dysfunction(ED)is ***,this study aimed to investigate the potential association between dietary niacin intake and the risk of *** logistic regression and restricted cubic splines(RCSs)were used to examine the relationship between dietary niacin intake and *** interaction analysis was performed to assess the impact of different subgroups on the study *** addition,1.1.propensity score matching(PSM)was employed to adjust for potential confounding factors,ensuring the reliability of the *** analyzed data were collected from the 2001.2004 National Health and Nutrition Examination Survey(NHANES)in the *** study encompassed 31.4 adults,among whom 863 participants were identified as having *** adjustments for potential confounders,the findings revealed that higher niacin intake,specifically in the highest tertile,was associated with a decreased risk of ED compared to that in the lowest tertile,showing an odds ratio(OR)of 0.56(95%confidence interval[CI]:0.37–0.85).Analysis of dose–response curves illustrated a negative correlation between dietary niacin intake and the risk of *** and interaction analyses fortified the consistency of these ***,PSM corroborated the validity of the *** study suggests an inverse association between dietary niacin intake and the risk of ***,establishing a cause-and-effect relationship remains elusive,and defining the safe threshold of niacin intake to prevent ED requires further investigation.

关键词： dietary niacin erectile dysfunction National Health and Nutrition Examination Survey propensity score matching

Effect of nano-graphite on mechanical properties and oxidation resistance of ZrB_(2)-SiC-graphite electrode ceramics

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Journal of Iron and Steel Research International 2024年第6期31卷 1502-1513页

作者： Bo-lin Yang Chang-liu Kuang {1.-long Liu Chao Yu Cheng-ji Deng Jun Ding The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrB_(2)-based ceramic composites were prepared by spark plasma sintering using ZrB_(2) powder prepared by molten salt method as raw material and SiC and nano-graphite as *** effects of nano-graphite addition on the physical properties and oxidation resistance of ZrB_(2)-based ceramic samples were *** results show that the addition of an appropriate amount of nano-graphite can effectively improve the density of ZrB_(2)-based ceramic composites and improve the physical properties of the *** flexural strength of the ceramic sample with 8 vol.%nano-graphite reached 41..54 MPa,which was 53.1.% higher than that of ZrB_(2)-SiC ceramic material(273.31.MPa),and its oxidation resistance was also significantly *** demonstrats that the addition of an appropriate amount of nano-graphite can effectively improve the physical properties and oxidation resistance of ZrB_(2)-SiC ceramic *** prolonging its service life in application and promoting the development of ZrB_(2)-based ceramic composites,it is of great significance for clean steel smelting.

关键词： ZrB_(2)-SiC-graphite electrode ceramic ZrB_(2)-based ceramic composite Nano-graphite Physical property Oxidation resistance

Helmholtz decomposition with a scalar Poisson equation in elastic anisotropic media

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Petroleum Science 2024年第3期21卷 1597-1610页

作者： Xin-Yu Fang Gang Yao Qing-Qing zheng Ping-Min Zhang Di Wu Feng-{1. Niu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China Department of Mathematics College of ScienceChina University of Petroleum(Beijing)Beijing102249China College of Geophysics China University of Petroleum(Beijing)Beijing102249China Department of Earth Environmental and Planetary SciencesRice UniversityHoustonTX77005UA

P-and S-wave separation plays an important role in elastic reverse-time *** can reduce the artifacts caused by crosstalk between different modes and improve image *** addition,P-and Swave separation can also be used to better understand and distinguish wave types in complex *** present,the methods for separating wave modes in anisotropic media mainly include spatial nonstationary filtering,low-rank approximation,and vector Poisson *** of these methods require multiple Fourier transforms or the calculation of large matrices,which require high computational costs for problems with large *** this paper,an efficient method is proposed to separate the wave mode for anisotropic media by using a scalar anisotropic Poisson operator in the spatial *** 2D problems,the computational complexity required by this method is 1.2 of the methods based on solving a vector Poisson ***,compared with existing methods based on pseudoHelmholtz decomposition operators,this method can significantly reduce the computational *** examples also show that the P and S waves decomposed by this method not only have the correct amplitude and phase relative to the input wavefield but also can reduce the computational complexity significantly.

关键词： Anisotropic media Scalar anisotropic Poisson equation Improved elastic wavefield decomposition