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The unsteady flow characteristics of water jet atomization in supersonic crossflow

PHYSICS OF FLUIDS 2025年第2期37卷

作者： Huang, Xixuan lin, zhiyong Gao, Yuchao Sun Yat Sen Univ Sch Aeronaut & Astronaut Shenzhen Campus66 Gongchang Rd Shenzhen 518107 Guangdong Peoples R China Sun Yat Sen Univ 135 Xingang Xi Rd Guangzhou 510275 Peoples R China

This investigation examines the atomization flow characteristics and instability mechanisms in a liquid jet in supersonic crossflow (LJISC). Through concurrent deployment of high-speed imaging and phase Doppler particle analysis, we successfully captured two distinct phenomena: the spanwise vortex formation at the atomization zone's lower boundary and the periodic generation and separation of irregular droplet clusters at its apex. Our observations reveal that droplets initially present in the subsonic region were entrained into the supersonic regime by the spanwise vortex, subsequently undergoing fragmentation due to elevated frequency oscillations. To further investigate the gas-liquid interactions in shear-dominated LJISC atomization, we conducted numerical simulations using interTwoPhaseLSELCentralFoam, a compressible two-phase interfacial flow solver developed within the OpenFOAM (R) framework. We identified a transitional plane demarcating the subsonic-supersonic flow boundary and applied proper orthogonal decomposition (POD) to analyze the temporal evolution of velocity fields across this plane. The POD analysis revealed that shear instability-induced velocity fluctuations in the incoming flow governed the systematic formation and detachment of droplet clusters. Additionally, our findings demonstrate that spanwise-aligned counter-rotating vortex pairs facilitated droplet migration across different velocity strata.

关键词： Vortex flow

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Numerical investigation of jet-wedge combinatorial initiation for oblique detonation wave in supersonic premixed mixture

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PHYSICS OF FLUIDS 2023年第2期35卷 1-12页

作者： Yao, Junyu lin, zhiyong Sun Yat sen Univ Sch Aeronaut & Astronaut Guangzhou 510006 Peoples R China

The jet-wedge combinatorial initiation (JWCI) is a novel functional form for initiating an oblique detonation wave (ODW) with reduced total drag within the oblique detonation combustor under the conditions of a low Mach number and low static pressure inflow. It can suppress the instability of the detached ODW. The evolution of the combustion wave during combinatorial initiation is dominated by the intersection between the bow shock wave and the oblique shock wave and consists of four stages: the shock-induced combustion stage, the shock-deflagration coupling stage, the hybrid combustion stage, and the oblique detonation stage. Three combustion regimes can be formed by using the JWCI: the shock-induced combustion regime, the hybrid combustion regime, and the oblique detonation combustion regime. These regimes have distinct characteristics of combustion and flow structure that can be controlled by changing two non-dimensional variables: the ratio of momentum flux (J) and the penetration ratio (PR). This is significant as it can facilitate the application of different combustion regimes under a variety of realistic flight conditions. In this study, the criterion for the transformation of the combustion regime is quantitatively investigated, and it is shown that the structure of the combustion wave does not transform until both non-dimensional variables have reached their respective thresholds. J is crucial for determining the combustion regime and facilitating its transformation, but the PR accounts only for the height of the combustion wave structure. The work is beneficial for research on the initiation of the ODW in applications of oblique detonation engines.

关键词： Detonation

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Association between composite dietary antioxidant index and atherosclerosis cardiovascular disease in adults: A cross-sectional study

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NUTRITION METABOLISM AND CARDIOVASCULAR DISEASES 2024年第9期34卷 2165-2172页

作者： lin, zhiyong Xie, Yuanyuan lin, Yi Chen, Xiyi Wenzhou Med Univ Affiliated Hosp & Yuying Childrens Hosp 2 Dept Cardiovasc & Thorac Surg 109 Coll West Rd Wenzhou 325027 Peoples R China Wenzhou Med Univ Affiliated Hosp 1 Dept Gen Practitioner Wenzhou 325027 Peoples R China Shanghai Univ Affiliated Hosp 3 Wenzhou Peoples Hosp Dept Endocrinol Wenzhou 325027 Zhejiang Peoples R China

Background and aim: The objective of our study was to examine the association between composite dietary antioxidant index (CDAI) and atherosclerotic cardiovascular disease (ASCVD) in adults. Methods and results: Data was gathered from the National Health and Nutrition Examination Survey (NHANES) between 2001 and 2018. To examine the connection between CDAI and ASCVD, multiple logistic regression analyses were performed. Restricted cubic splines were utilized to examine non-linear correlations, and the inflection point was identified using a two-piecewise linear regression approach. Subgroup analyses were performed to demonstrate stability of results. A total of 44,494 individuals were included in the study. The multivariate logistic regression model was fully adjusted and revealed an odds ratio of 0.968 (95% CI: 0.959-0.978;P < 0.001) for the correlation between CDAI and ASCVD. Furthermore, individuals in the highest quartile of CDAI exhibited a decreased risk of ASCVD compared to those in the lowest quartile [0.716 (0.652-0.787);P < 0.001]. Moreover, restricted cubic spline (RCS) analysis revealed non-linear relationship between CDAI and ASCVD, with inflection point at -0.387. The analysis of subgroups showed that the importance of CDAI remained consistent among various age, sex, race, body mass index (BMI), and physical activity. Conclusions: Our research revealed an inverse and non-linear relationship between CDAI and ASCVD in adults. The implications of these findings are significant for future studies and the formulation of dietary guidelines. (c) 2024 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Composite dietary antioxidant index Atherosclerotic cardiovascular disease NHANES Diet

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Separated kin: location of multiple children and mental health trajectories of older parents in rural China

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AGING & MENTAL HEALTH 2023年第2期27卷 425-433页

作者： lin, zhiyong Tang, Dan Univ Texas Austin Ctr Aging & Populat Sci Austin TX 78712 USA Univ Texas Austin Populat Res Ctr Austin TX 78712 USA Renmin Univ China Populat Dev Studies Ctr Beijing Peoples R China

Objective This study examines the longitudinal association between the location of multiple children and depressive symptoms of older parents in rural China, where massive rural-to-urban migration has profoundly altered the family life of the aging population. Methods Using seven waves of panel data from the Longitudinal Study of Older Adults in Anhui Province (2001-2018, N = 8,253) and multilevel growth curve models, this study compares mental health trajectories of old parents across different compositions of local and migrant children over an 18-year time period. Results The results show that older parents with a greater share of adult children who had migrated away not only scored worse mental health on average, but also experienced a more rapid increase in depressive symptoms across ages, after accounting for other covariates. Further, older adults who had their most children migrated away for a longer period of time suffered from the steeper rate of increase in depressive symptoms as they got older. Conclusions We suggest that it is not the geographic locality of a single child but the location of multiple children that matters for parental mental health in later life.

关键词： Intergenerational proximity multiple children rural China depressive symptoms

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Changing attitudes toward homosexuality in South Korea, 1996-2018

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SOCIAL SCIENCE RESEARCH 2024年 118卷 102972页

作者： lin, zhiyong Lee, Jaein Univ Texas San Antonio Dept Sociol & Demog San Antonio TX USA Arkansas State Univ Dept Sociol & Criminol Jonesboro AR 72401 USA

Women are often considered more liberal than men on controversial social issues, but gender gaps in sociopolitical attitudes across different age groups have not been fully explored. This study challenges the taken-for-granted gender differences in public attitudes toward homosexuality by examining both between-gender gaps and within-gender changes across the life course. Using data from five waves of the World Values Survey in South Korea, we explore gender and age differences in Korean adults' attitudes toward homosexuality from 1996 to 2018. Consistent with previous research, people become more conservative as they get older, and in general, women are more accepting of homosexuality than men, accounting for sociodemographic covariates. However, this gender difference is conditioned by people's life stages. Only among young adults (aged 18-29) were female respondents more accepting of homosexuality than their male counterparts. For people aged 30 and older, there are no significant gender differences in attitudes, and for both women and men, homosexuality is mostly unacceptable during their mid (aged 50-59) and late adulthood (aged 60+). Further mediation investigation has shown gendered mechanisms behind age differences in homosexuality acceptability. For both women and men, traditional family/ gender attitudes provide significant explanations about age differences in homosexuality, while for women, not for men, family status, especially the number of children, makes older women more conservative in homosexuality issues. We suggest that heteropatriarchal social structures may lead to a resistance to attitudinal changes in non-traditional family forms, such as homosexuality.

关键词： Homosexuality Public opinion Gender South Korea

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Race/Ethnicity, Nativity, and Gender Disparities in Mental Health Trajectories from Mid- to Later-Life: A Life Course-Intersectional Approach

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JOURNAL OF RACIAL AND ETHNIC HEALTH DISPARITIES 2024年第6期11卷 3544-3560页

作者： Liu, Jingwen lin, zhiyong Univ Maryland Dept Sociol 3834 Campus DrParren Mitchell Art Sociol Bldg College Pk MD 20742 USA Univ Texas San Antonio Dept Sociol One UTSA CircleMS 4-02-66 San Antonio TX 78249 USA Univ Texas Austin Populat Res Ctr 305 E 23rd StStop G1800 Austin TX 78712 USA

BackgroundNumerous studies have highlighted mental health disparities based on race/ethnicity, nativity, and gender across different life stages. However, few have investigated how the intersectionality of these factors influences mental health trajectories during midlife to late life. This study fills this gap by adopting a life course-intersectional approach, viewing mental health trajectories as dynamic processes shaped by the combined influences of race/ethnicity, nativity, and gender. It explores social, psychological, and physiological pathways contributing to these *** data from the Health and Retirement Study (2006-2018;N = 38,049 observations) and growth curve models, this study examines how intra-individual trends in depressive symptoms (measured as CES-D scale, 07) are influenced by the intersection of race/ethnicity, nativity, and gender. It also investigates the impact of objective and subjective social isolation and physical health on group disparities in mental health *** findings reveal that, during mid- to early late-life, most Black and Hispanic Americans experience higher levels of depressive symptoms compared to their White counterparts (disparities ranging from 0.184 to 0.463 for men and 0.117 to 0.439 for women). However, this disadvantage diminishes for US-born Hispanic men and US-born Black women (0.014-0.031 faster decrease rates compared to US-born White), while it intensifies for Hispanic immigrants (0.017-0.018 slower decrease rates compared to US-born White) in advanced ages. Mediation analysis demonstrates that both social isolation and physical health contribute to these disparities, with physical health explaining a larger portion, particularly in differences between immigrant Hispanic women and US-born *** study underscores the importance of a life course-intersectional approach in understanding mental health disparities. It emphasizes the need for improved social welfare syst

关键词： Race/ethnicity Nativity Gender Depressive symptoms Life course Intersectionality

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A Fine-Scale and Highly Reliable Ground and Canopy Top Extraction Method Using ICESat-2 Data

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IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING 2024年 17卷 5266-5279页

作者： Chang, Jingxin Jiang, Yonghua lin, zhiyong Tan, Meilin Wuhan Univ Sch Remote Sensing Informat Engn Wuhan 430079 Peoples R China Inner Mongolia Autonomous Reg Surveying & Mapping Hohhot 010050 Peoples R China

The ice, cloud, and land elevation satellite-2 (ICESat-2) is equipped with an advanced topographic laser altimeter system (ATLAS) that obtains small spots and high-density photon data. ATLAS has the potential for high-precision detection of global surfaces and helps calculate global carbon sinks. One important carbon sink includes forests and making it critical to precisely measure their carbon storage and obtain both ground and top-of-canopy (TOC) levels of vegetation. Here, we explored a precise and highly reliable ground and TOC detection method based on ICESat-2 data to accurately remove noise and classify photons. This method can be adapted to different scenes and topographies. The first step included the removal of pronounced dispersion noise and pseudosignal photon aggregation noise. We introduced two algorithms for coarse noise removal-an adaptive threshold ellipsoid filter algorithm and an outlier photon cluster removal algorithm based on the photon group distance. Then, the local outlier factor algorithm was modified to remove the noise of near-signal photons to obtain the result of fine denoising. Finally, the modified local direction center algorithm was combined with the uniaxial inverse distance-weighted statistics to distinguish the ground from the TOC. Across varied scenes and terrains, the proposed denoising method demonstrated an overall accuracy exceeding 0.94. Additionally, the root-mean-square error of the ground and TOC obtained via the classification method was under 1.4 m and 3.2 m, respectively. These findings highlight that this method has a high level of robustness in effectively detecting both the ground and TOC.

关键词： Photonics Noise reduction Laser radar Carbon Statistical analysis Noise measurement Orbits Ground photon ice cloud and land elevation satellite-2 (ICESat-2) photon classification photon noise removal algorithm remote sensing top-of-canopy (TOC) photon

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Efficient Separation of Iron and Alumina in Red Mud Using Reduction Roasting and Magnetic Separation

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MINING METALLURGY & EXPLORATION 2024年第3期41卷 1543-1552页

作者： Wang, Hongyang Zhao, Yuqi lin, zhiyong Shen, Leiting Anhui Univ Sci & Technol Sch Mat Sci & Engn Huainan 232001 Peoples R China Cent South Univ Sch Met & Environm Changsha 410083 Peoples R China Anhui Univ Sci & Technol Anhui Gener Technol Res Ctr New Mat Coal Based Sol Huainan 232001 Peoples R China

Gibbsite-type bauxite is the main material for alumina extraction by Bayer process globally, while the iron in red mud is difficult to use for the high alumina content. Therefore, the efficient separation of iron and alumina is the premise for the resource utilization of red mud. In this work, the separation of iron and alumina in red mud containing 47.45% Fe and 11.58% Al2O3 was studied through reduction roasting followed by magnetic separation. The analysis methods of XRD, VSM, SEM, and EDS were used to investigate the phase transformation of red mud during reduction roasting. Results show that hematite can be firstly reduced into magnetite, and alumogoethite into magnetite and alumina. Then, the magnetite reduction undergoes the process of Fe3O4 -> FeO -> Fe, while alumina can react with FeO to form hercynite. The hercynite is ultimately reduced into metallic iron and alumina at elevated temperature. The specific saturation magnetization of reduced product is closely related to its main minerals, that is, the specific saturation magnetization of magnetite and metallic iron is higher than that of wustite and hercynite. The mass ratio of Fe to Al2O3 in magnetic concentrate increases with roasting temperature, from 4.55 at 600 degrees C to 10.27 at 1200 degrees C. Therefore, efficient separation of iron and alumina in red mud could be achieved through deep reduction-magnetic separation.

关键词： Red mud Alumogoethite Reduction roasting Magnetic separation Concentrate

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Analysis of coupled-waves structure and propagation characteristics in hydrogen-assisted kerosene-air two-phase rotating detonation wave

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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2022年第7期47卷 4868-4884页

作者： Huang, Xixuan lin, zhiyong Sun Yat sen Univ Sch Aeronaut & Astronaut Guangzhou 510275 Peoples R China

In order to investigate the structure and propagation characteristics of hydrogen-assisted kerosene (liquid phase)-air rotating detonation, a modified solver based on OpenFOAM (R) was proposed and utilized to simulate detonation in the mixture of hydrogen, liquid kerosene and air. The obtained results show that evaporation waves exist in the discrete liquid mist detonation, and the coupled-waves structure formed by the evaporation wave (EW) and the incident shock wave (ISW) propagates upstream. By analyzing the overall and instantaneous propagation characteristics, it is found that the propagation speed of the detonation wave increases with the increase of the equivalence ratio at the fuel rich state. Increasing the droplet size will cause the evaporation wave to be further downstream relative to the ISW, resulting in lower evaporating pressure. The effect of EW on ISW is accomplished by the blast wave traveling upstream which is generated by droplet reaction, while EW is influenced by the ISW by modulating the droplet enthalpy and the pressure attenuation following ISW. Part of the droplet reaction energy is held in the gap between the EW and ISW, consequently the gap acts as an energy storage piston, regulating the ISW and EW propagation speeds. The combustion of droplets with smaller sizes imposes more positive feedback on their evaporation, and increasing the total temperature of the pre-mixed gas promotes the interaction between the EW and the ISW, resulting in a more steady propagating overall structure. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

关键词： Rotating detonation Two-phase flow Hydrogen-assisted combustion Coupled-waves structure

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Global research trends on immunotherapy in cancer: A bibliometric analysis

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HUMAN VACCINES & IMMUNOTHERAPEUTICS 2023年第2期19卷 2219191页

作者： Yao, Zhichao lin, zhiyong Wu, Weijia Second Affiliated Hosp Dept Gen Surg Wenzhou Peoples R China Wenzhou Med Univ Yuying Childrens Hosp Wenzhou Peoples R China Second Affiliated Hosp Dept Cardiovasc & Thorac Surg Wenzhou Peoples R China Yuying Childrens Hosp Wenzhou Med Univ Wenzhou Peoples R China Second Affiliated Hosp Dept Cardiovasc & Thorac Surg 1111 Wenzhouda St Wenzhou Peoples R China Wenzhou Med Univ Yuying Childrens Hosp 1111 Wenzhouda St Wenzhou Peoples R China

Cancer immunotherapy has been gradually introduced and has undergone noteworthy developments in recent years. The number of scientific publications has been expanding, and the progression in this field has been rapidly evolving with time. This study aimed to use bibliometric analysis to examine the past 20 years of research on cancer immunotherapy and identify future hotspots. A literature search for medical publications on immunotherapy in cancer from 2000 to 2021 was conducted in the Web of Science Core Collection on March 1, 2022. Visualization analysis was performed using VOSviewer software (version 1.6.16). From 2000 to 2021, a total of 18,778 publications were retrieved. Annual publication output grew rapidly from 366 in 2000 to 3,194 in 2021. The USA issued the largest number of publications (n = 6,739, 35.89%), with the University of Texas System making the largest contribution (n = 802, 4.27%). A total of 976 meaningful topics were identified and further classified into 4 different clusters (immune mechanism, cancer biology, immunotherapy and clinical trials). The most common research topics included 'expression', 'chemotherapy', 'dendritic cells', 'pembrolizumab' and 'open-label'. Highly identified cancer types included hepatocellular, bladder, breast and lung cancer. A shift in popularity from mechanism research to clinical trials was observed, indicating that clinical application would be the center of attention in the future. Attention has been given to the field of cancer immunotherapy, and this trend will continue in the future. This study provides an unbiased visualization analysis on this topic in a scale-efficient manner for further research.

关键词： Immunotherapy cancer Web of Science VOSviewer visualization

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