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Numerical study on influence of protrusion heights on Reynolds stress and viscous stress variations in turbulent vortical structures

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Chinese Journal of Aeronautics 2024年第9期37卷 59-71页

作者： Zhiping LI Long HE Jingsai ZHOU Yueren zuo Yao YIN Peng ZHANG Bo MENG Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBejing 100191China Institute of Acoustics Chinese Academy of SciencesBeijing 100190China College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China

Analysing the infuence mechanism of the riblet protrusion height on turbulent drag components is more beneficial in organising the vortical structure over the riblet ***,the Large Eddy Simulation(LES)is used to investigate the vortex structure over the rib-let surface with different protrusion ***,the variations of Reynolds stress and viscous shear stress in a turbulent channel are *** a result,the drag reduction rate increases from 3.4%when the riblets are completely submerged in the turbulent boundary layer to 7.9%when the protrusion height is *** analysis shows that the protrusion height affects the streamwise vortices and the normal diffusivity of spanwise and normal vortices,thus driving the variation of Reynolds *** with the smooth surface,the vorticity strength and the number of streamwise vortices are weakened near the wall but increase in the logarithmic layer with increased protrusion ***,the normal diffusivity of spanwise vorticity decreases with the increase of protrusion height,and the normal diffusivity of normal vorticity is the smallest when the protrusion height is ***,the protrusion height affects the velocity gradient of the riblet tip and riblet valley,thus driving the variation of viscous shear *** the increase of protrusion height,the velocity gradient of the riblet tip increases dramatically but decreases in the riblet valley.

关键词： Riblet Dragreduction Protrusion height Vortical structure Vortexdiffusivity Reynolds stress Viscous stress

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Parental Educational Expectations,Academic Pressure,and Adolescent Mental Health:An Empirical Study Based on CEPS Survey Data

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International Journal of Mental Health Promotion 2024年第2期26卷 93-103页

作者： Tao Xu Fangqiang zuo Kai Zheng Department of Social Work College of International Education and Social DevelopmentZhejiang Normal UniversityJinhua321004China Department of Economics and International Trade School of EconomicsManagement&LawHubei Normal UniversityHuangshi435002China

Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating ***:This study was based on the baseline data of the China Education Panel Survey,which was collected within one school year during 2013–*** included 19,958 samples from seventh and ninth graders,who ranged from 11 to 18 years *** removing missing values and conducting relevant data processing,the effective sample size for analysis was *** OLS(Ordinary Least Squares)multiple linear regression analysis was used to examine the relationship between parental educational expectations,academic pressure,and adolescents’mental health *** addition,we established an interaction term between parents’educational expectations and academic pressure to investigate the moderating effect of academic ***:The study found that adolescents whose parents had high educational expectations reported less mental health problems.(β=−0.195;p<0.001).Additionally,adolescents who had high academic pressure reported more mental health problems.(β=0.649;p<0.001).Furthermore,the study found that academic pressure had a significant moderating effect on the relationship between parental educational expectations and adolescents’mental health problems(β=0.082;p<0.001).Conclusion:Parental educational expectations had a close relationship with adolescents’mental health problems,and academic pressure moderated this *** those adolescents with high levels of academic pressure,the association between high parental educational expectations and mental health problems became *** the contrary,for those adolescents with low levels of academic pressure,the association between high parental educational expectations and mental health problems became *** findings shed new light on how parental educational expectations affected adolescent mental health problems and h

关键词： Parental educational expectations academic pressure adolescent mental health problems

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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses

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Journal of Forestry Research 2024年第2期35卷 42-53页

作者： Ting Wang Qing Xu Beibei Zhang Deqiang Gao Ying Zhang Jing Jiang Haijun zuo Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China College of Agronomy and Agricultural Engineering Liaocheng UniversityLiaocheng 252000People’s Republic of China Department of Forest and Conservation Sciences Faculty of ForestryUniversity of British ColumbiaVancouverBC V6T 1Z4Canada

Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate ***,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management *** this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of *** capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were ***,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water *** removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water *** general,thinning may be an appropriate management measure to promote *** WUE to cope with seasonal droughts under future extreme climates.

关键词： Stable carbon isotope Water use efficiency Thinning Understory removal Photosynthetic capacity Needle water potential

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Predictive value of NLR, Fib4, and APRI in the occurrence of liver failure after hepatectomy in patients with hepatocellular carcinoma

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 155-165页

作者： Tian-zuo Kuang Meng xiao Yong-Fan Liu Department of Hepatobiliary Surgery Ji’an Central People’s HospitalJi’an 343000Jiangxi ProvinceChina

BACKGROUND Neutrophil-lymphocyte ratio(NLR),fibrosis index based on four factors(Fib4),aspartate aminotransferase-to-platelet ratio index(APRI)can be used for prognostic evaluation of hepatocellular ***,no study has established an individualized prediction model for the prognosis of hepatocellular carcinoma based on these *** To screen the factors that affect the prognosis of hepatocellular carcinoma and establish a nomogram model that predicts postoperative liver failure after hepatic resection in patients with hepatocellular *** In total,220 patients with hepatocellular carcinoma treated in our hospital from January 2022 to January 2023 were *** were divided into 154 participants in the modeling cohort,and 66 in the validation *** analysis of the changes in NLR,Fib4,and APRI levels in 154 patients with hepatocellular carcinoma before liver resection and at 3 mo,6 mo,and 12 mo postoperatively was *** logistic regression to analyze the influencing factors on the occurrence of liver failure in hepatocellular carcinoma patients,roadmap prediction modeling,and validation,patient work characteristic curves(ROCs)to evaluate the predictive efficacy of the model,calibration curves to assess the consistency,and decision curve analysis(DCA)to evaluate the model’s validity were also *** Binary logistic regression showed that Child-Pugh grading,Surgical site,NLR,Fib4,and APRI were all risk factors for liver failure after hepatic resection in patients with hepatocellular *** modeling cohort built a column-line graph model,and the area under the ROC curve was 0.986[95%confidence in terval(CI):0.963-1.000].The patients in the validation cohort utilized the column-line graph to predict the probability of survival in the validation cohort and plotted the ROC curve with an area under the curve of the model of 0.692(95%CI:0.548-0.837).The deviation of the actual outcome curves from the c

关键词： Hepatocellular carcinoma Hepatic resection Liver failure Influencing factors Columnar graphs

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离子辐照对材料磁性的调控及其应用

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物理学报 2024年第13期73卷 28-43页

作者：郭玺左亚路崔宝山申铁龙盛彦斌席力兰州大学物理科学与技术学院兰州730000 中国科学院近代物理研究所兰州730000

离子辐照技术具有离子束能量密度高、实验条件可精确控制,且不受化学剂量比影响的特点,利用离子束辐照材料,可实现定向掺杂,或精确引入和调控现缺陷位和密度等优势,因此在多个领域,如材料改性、芯片制造、生物医学、能源及化工领域都得... 详细信息

离子辐照技术具有离子束能量密度高、实验条件可精确控制,且不受化学剂量比影响的特点,利用离子束辐照材料,可实现定向掺杂,或精确引入和调控现缺陷位和密度等优势,因此在多个领域,如材料改性、芯片制造、生物医学、能源及化工领域都得到了广泛应用.尤其在磁性材料改性领域,该技术能够通过细致控制离子束的能量、剂量和辐照方向,实现对磁性材料的定制化性能优化.为进一步提升磁性材料的性能并探索新的磁性器件,本文深入地探讨了离子辐照如何精确调制各种磁相互作用,并分析其对自旋霍尔效应和磁结构动力学的影响.首先着重介绍了离子辐照在调控垂直磁各向异性、交换偏置及RKKY相互作用等磁性特征方面的最新研究成果.这些调控手段对于理解和优化磁性材料的微观结构和性质至关重要.接着,本文详细地探讨了离子辐照在调控自旋轨道力矩器件中的重要作用.这些应用展示了离子辐照技术在设计高性能磁性存储和处理器件方面的潜力.最后,还讨论了辐照离子种类、能量、剂量、辐照面积等参数对磁斯格明子成核位置、密度、尺寸、稳定性以及磁斯格明子霍尔效应的调控作用,阐明了离子辐照改变磁斯格明子生成、湮灭、运动规律等方面的内在机理,为制备基于磁斯格明子运动的低功耗存储器件提供新的途径.此外,本文还就离子辐照技术在未来多功能磁性传感器及信息存储磁介质制备方面的可能应用进行了前瞻性分析.离子辐照技术为磁性材料的性能调控和应用扩展提供了新的可能性.随着研究的深入,这项技术有望在未来的材料科学、电子器件以及信息技术等多个领域发挥更大的作用.

关键词：离子辐照磁相互作用能自旋轨道力矩磁斯格明子

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Andrographolide Attenuates Noise-Induced Hearing Loss by Ameliorating Cochlear Inflammation

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World Journal of Traditional Chinese Medicine 2024年第2期10卷 204-212页

作者： Meng-Hua Li Wan-Qi Wang Li-Ting Zheng Meng Bing Chen Yang Chu Miao Qiao zuo-Li Zhang Konduru Naveena Yong Pan Yun-Shi Zhang He Sun xiao-Hui Ma xi Shi Artificial Auditory Laboratory of Jiangsu Province Xuzhou Medical UniversityXuzhouChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouChina Department of ENT Beijing Friendship HospitalCapital Medical UniversityBeijingChina National Key Laboratory of Chinese Medicine Modernization Tasly AcademyTasly Pharmaceutical Group Co.Ltd.TianjinChina Endoscopy Center Ankang People's HospitalAnkangChina Department of Respiratory Medicine Xuzhou Infectious Diseases HospitalAffiliated Hospital of Xuzhou Medical UniversityXuzhouChina Department of ENT The People's Hospital of Rongchang DistrictChongqingChina

Objective:This study aimed to explore andrographolide's mechanism of action and its protective effect on noise-induced hearing loss(NIHL).Materials and Methods:A mice animal model for NIHL was established through exposure to broadband noise at 120 d B sound pressure level for 4 *** analysis and pharmacodynamic experiments were carried ***:Andrographolide enters the inner ear and effectively prevents hearing damage following noise exposure in the mice model for permanent hearing ***,treatment with andrographolide inhibited the excessive activation of inflammatory factors in the cochleae of noise-exposed ***:Andrographolide might be a promising candidate for auditory protective drug investigation.

关键词： Andrographolide anti-inflammatory auditory protection noise-induced hearing loss traditional Chinese medicine compound

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A layered multifunctional framework based on polyacrylonitrile and MOF derivatives for stable lithium metal anode

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Journal of Energy Chemistry 2024年第6期93卷 282-288,I0007页

作者： Fanfan Liu Peng zuo Jing Li Pengcheng Shi Yu Shao Linwei Chen Yihong Tan Tao Ma Engineering Research Center of High-frequency Soft Magnetic Materials and Ceramic Powder Materials of Anhui Province School of Chemistry and Material EngineeringChaohu UniversityHefei 238024AnhuiChina Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Pharmacy Anhui University of Chinese MedicineHefei 230012AnhuiChina School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006GuangdongChina Jiujiang DeFu Technology Co. Ltd.Jiujiang 332000JiangxiChina

Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy ***,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li *** promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical *** from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 mA/cm~***,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical *** the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 ***,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction *** electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks.

关键词： Lithium metal anode Layered multifunctional framework Ions flux redistribution Electrical insulation/conduction structure Uniform Li deposition

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Manipulation of magnetocaloric and elastocaloric effects in Ni-Mn-In alloys by lattice volume and magnetic variation:Effect of Co and Fe co-doping

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Journal of Materials Science & Technology 2024年第5期172卷 156-165页

作者： xinzeng Liang Chi Zhang Jing Bai Jianglong Gu Yudong Zhang Claude Esling xiang Zhao Liang zuo School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang 110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Laboratoire d’Étude des Microstructures et de Mécanique des Matériaux LEM3 CNRSUMR 7239University of Lorraine57045 MetzFrance

The effects of Co and Fe co-doping Ni-Mn-In alloy on the phase stability,lattice parameters,mag-netic properties,and electronic structures are systematically investigated by using the first-principles *** indicate that Fe atoms replace the excess Mn2 atoms by direct and indirect coex-istence(Fe→Mn 2 and Fe→In→Mn2);Co substitutes the Ni atoms by direct substitution(Co→Ni)for the Ni-Mn-In *** austenites all exhibit the ferromagnetic(FM)state for the studied *** NM martensites are in the ferrimagnetic(FIM-1)state for the Ni_(2)Mn_(1.5)In_(0.5),Ni_(2)Mn_(1.25)In_(0.5)Fe 0.25,Ni_(1.75)Mn_(1.5)In_(0.5)Co_(0.25),and Ni_(1.75)Mn_(1.25)In_(0.5)Co_(0.25)Fe 0.25 alloys,while the other compositions are in the FM *** phase stability of austenite and martensite decreases with increasing Co and Fe co-doping.A magnetic-structural coupling transition occurs at x<0.25 and y<*** Ni_(1.91)Mn_(1.5)In_(0.5)Co_(0.08)and Ni_(1.91)Mn_(1.42)In_(0.5)Co_(0.08)Fe_(0.08)alloys exhibit an A→6M→NM transformation,accompanied by a magnetic *** Co and Fe are co-doped,the hybridization strength between Co and Fe is greater than that between Co/Fe and *** enhancement of magnetocaloric and elastocaloric effects is favored by larger magnetization difference(△M)and lattice volume change(△V/V_(0)).Based on the calculated phase stability,magneto-structure coupling,△V/V 0 and c/a ratio,one can predict that the Ni_(2)-x Mn_(1.5)-y In_(0.5)Co x Fe y alloy with Co content 0≤x≤0.25 and Fe content 0≤y≤0.05 is predicted to have good magneto-controlled functional behavior.

关键词： Ni-Mn-In-Co-Fe Phase stability Magnetocaloric effect Elastocaloric effect

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Long-term exposure to aryl hydrocarbon receptor agonist neburon induces reproductive toxicity in male zebrafish(Danio rerio)

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Journal of Environmental Sciences 2024年第8期142卷 193-203页

作者： Fucong Zhang Chen Tang Yue Zhu Qian Wang xin Huang Chunyan Yang Chengyong He Zhenghong zuo Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems School of Life SciencesXiamen UniversityXiamen 361102China

Neburon is a phenylurea herbicide that is widely used worldwide,but its toxicity is poorly *** our previous study,we found that neburon has strong aryl hydrocarbon receptor(AhR)agonist activity,but whether it causes reproductive toxicity is not *** the present study,zebrafish were conducted as a model organism to evaluate whether environmental concentrations of neburon(0.1,1 and 10μg/L)induce reproductive disorder in *** exposure to neburon for 150 days from embryo to adult,that the average spawning egg number in high concentration group was 106.40,which was significantly lower than 193.00in control *** result was mainly due to the abnormal male reproductive behavior caused by abnormal transcription of genes associated with reproductive behavior in the brain,such as *** proportions of spermatozoa in the medium and high concentration groups were 82.40%and 83.84%,respectively,which were significantly lower than 89.45%in control *** result was mainly caused by hormonal disturbances and an increased proportion of apoptotic *** hormonal disruption was due to the significant changes in the transcription levels of key genes in the hypothalamus-pituitary-gonadal axis following neburon *** treatment also significantly activated the AhR signaling pathway,causing oxidative stress damage and eventually leading to a significant increase in apoptosis in the exposed ***,these data filled the currently more vacant profile of neburon toxicity and might provide information to assess the ecotoxicity of neburon on male reproduction at environmentally relevant concentrations.

关键词： Zebrafish Neburon Male reproductive toxicity HPG axis AhR agonist

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Wetting sub-nanochannels via ionic hydration effect for improving charging dynamics

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Green Energy & Environment 2024年第3期9卷 473-480页

作者： Yayun Shi xiaoli Zhao Qihang Liu Zhenghui Pan Congcong Liu Shanyi Zhu Zhijun zuo xiaowei Yang State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan030024China School of Materials Science and Engineering Tongji UniversityShanghai201804China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai200240China

The ionic transport in sub-nanochannels plays a key role in energy storage,yet suffers from a high energy *** sub-nanochannels is crucial to accelerate ionic transport,but the introduction of water is challenging because of the hydrophobic extreme *** propose wetting the channels by the exothermic hydration process of pre-intercalated ions,the effect of which varies distinctly with different ionic hydration structures and *** to the failed pre-intercalation of SO_(4)^(2-),HSO_(4)^(-) with weak hydration energy results in a marginal effect on the HOMO(Highest Occupied Molecular Orbital)level of water to avoid water splitting during the electrochemical ***,the ability of water introduction is reserved by the initial incomplete dissociation state of HSO_(4)^(-),so the consequent exothermic reionization and hydration processes of the intercalated HSO_(4)^(-) promote the water introduction into sub-nanochannels,finally forming the stable confined water through hydrogen bonding with functional *** wetted channels exhibit a significantly enhanced ionic diffusion coef-ficient by~9.4 times.

关键词： Sub-nanochannels Ionic hydration Ionic transport Supercapacitors Confined water

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