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Multi-Scale Design and Optimization of Composite Material Structure for Heavy-Duty Truck Protection Device

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1961-1980页

作者： yanhui zhang Lianhua Ma Hailiang Su Jirong Qin Zhining Chen Kaibiao Deng School of Mechanical and Automotive Engineering Guangxi University of Science and TechnologyLiuzhou545006China Commercial Vehicle Technology Center Dongfeng Liuzhou Automobile Co.Ltd.Liuzhou545005China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510641China

In this paper,to present a lightweight-developed front underrun protection device(FUPD)for heavy-duty trucks,plain weave carbon fiber reinforced plastic(CFRP)is used instead of the original high-strength steel.First,the mechanical and structural properties of plain carbon fiber composite anti-collision beams are comparatively analyzed from a multi-scale perspective.For studying the design capability of carbon fiber composite materials,we investigate the effects of TC-33 carbon fiber diameter(D),fiber yarn width(W)and height(H),and fiber yarn density(N)on the front underrun protective beam of carbon fiber compositematerials.Based on the investigation,a material-structure matching strategy suitable for the front underrun protective beam of heavy-duty trucks is proposed.Next,the composite material structure is optimized by applying size optimization and stack sequence optimization methods to obtain the higher performance carbon fiber composite front underrun protection beam of commercial vehicles.The results show that the fiber yarn height(H)has the greatest influence on the protective beam,and theH1matching scheme for the front underrun protective beamwith a carbon fiber composite structure exhibits superior performance.The proposed method achieves a weight reduction of 55.21% while still meeting regulatory requirements,which demonstrates its remarkable weight reduction effect.

关键词： Structural optimization front underrun protection device carbon fiber reinforced plastic multi-scale model lightweight design

Tuning interaction strength between CeO_(2) and iridium to promote CO oxidation over Ir/TiO_(2)

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Journal of Rare Earths 2024年第4期42卷 651-659页

作者： Lu Dai Binghua Li Yuhan Peng Xianwei Hao Runquan Xuan Hua Huang Yiming Bi Liping Xu yanhui zhang Yun Guo Fangqi Du Li Wang Hui Wang Technology Center China Tobacco Zhejiang Industrial Co.Ltd.Hangzhou310024China Research Institute of Industrial Catalysis East China University of Science and TechnologyShanghai200237China

The interaction between support and noble metal plays a crucial role in heterogeneous catalysis design.However,how to tune metal support interactions to optimize the activity still needs further exploration.CeO_(2) was introduced to promote CO oxidation ove r Ir/TiO_(2) by adjusting the interaction strength between iridium(Ir)and CeO_(2).The strong interaction between Ir and CeO_(2) blocks CO adsorption and causes low CO oxidation activity.However,introducing CeO_(2) on Ir/TiO_(2) produces localized interaction between Ir and CeO_(2),which can tune the surface electronic state of Ir,so a"volcano curve"relationship between CO oxidation activity and electronic state is built.Limited amount of CeO_(2) on Ir/TiO_(2)(Ir/Ce_(0.2)Ti)leads to CO complete oxidization at 22℃,and a new pathway for CO oxidation was explored.The study demonstrates that the utilization of tuning interaction strength between active metal and support is a potential method to increase the catalytic activity.

关键词： CO oxidation CeO_(2) Localized interaction Interaction strength Supported Ir catalysts Rareearths

Influence of Kerr Effect on Second-Order Nonlinearity Induced Transparency

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Wuhan University Journal of Natural Sciences 2024年第1期29卷 67-73页

作者： zhang Zhiqiang ZHOU yanhui College of Architectural Engineering Zhengzhou Business UniversityZhengzhou 451200HenanChina Quantum Information Research Center Shangrao Normal UniversityShangrao 334001JiangxiChina

We theoretically study the effect of Kerr effect on the second-order nonlinearity induced transparency in a double-resonant optical cavity system.We show that in the presence of the Kerr effect,as the strength of the Kerr effect increases,the absorption curve exhibits an asymmetric-symmetric-asymmetric transition,and the zero absorption point shifts with the increase of the Kerr effect.Furthermore,by changing the strength of the Kerr effect,we can control the width of the transparent window,and the position of the zero-absorption point and meanwhile change the left and right width of the absorption peak.The asymmetry absorption curve can be employed to improve the quality factor of the cavity when the frequency detuning is tuned to be around the right peak.The simple dependence of the zeroabsorption point on the strength of Kerr effect suggests that the strength of Kerr effect can be measured by measuring the position of the zero-absorption point in a possible application.

关键词： Kerr effect second-order nonlinearity induced transparency nonlinear optics quantum optics

Evaluation of rainfall threshold models for debris flow initiation in the Jiangjia Gully,Yunnan Province,China

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Journal of Mountain Science 2024年第6期21卷 1799-1813页

作者： YANG Hongjuan zhang Shaojie HU Kaiheng WEI Fangqiang LIU yanhui State Key Laboratory of Mountain Hazards and Engineering Resilience Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China Chongqing School University of Chinese Academy of SciencesChongqing 400714China China Institute of Geo-Environment Monitoring Beijing 100081China

Systematically determining the discriminatory power of various rainfall properties and their combinations in identifying debris flow occurrence is crucial for early warning systems.In this study,we evaluated the discriminatory power of different univariate and multivariate rainfall threshold models in identifying triggering conditions of debris flow in the Jiangjia Gully,Yunnan Province,China.The univariate models used single rainfall properties as indicators,including total rainfall(R_(tot)),rainfall duration(D),mean intensity(I_(mean)),absolute energy(Eabs),storm kinetic energy(E_(s)),antecedent rainfall(R_(a)),and maximum rainfall intensity over various durations(I_(max_dur)).The evaluation reveals that the I_(max_dur)and Eabs models have the best performance,followed by the E_(s),R_(tot),and I_(mean)models,while the D and R_(a)models have poor performances.Specifically,the I_(max_dur)model has the highest performance metrics at a 40-min duration.We used logistic regression to combine at least two rainfall properties to establish multivariate threshold models.The results show that adding D or R_(a)to the models dominated by Eabs,E_(s),R_(tot),or I_(mean)generally improve their performances,specifically when D is combined with I_(mean)or when R_(a)is combined with Eabs or E_(s).Including R_(a)in the I_(max_dur)model,it performs better than the univariate I_(max_dur)model.A power-law relationship between I_(max_dur)and R_(a)or between Eabs and R_(a)has better performance than the traditional I_(mean)–D model,while the performance of the E_(s)–R_(a)model is moderate.Our evaluation reemphasizes the important role of the maximum intensity over short durations in debris flow occurrence.It also highlights the importance of systematically investigating the role of R_(a)in establishing rainfall thresholds for triggering debris flow.Given the regional variations in rainfall patterns worldwide,it is necessary to evaluate the findings of this study across diverse watersheds.

关键词： Rainfall threshold Logistic regression Maximum rainfall intensity Absolute energy Antecedent rainfall

Quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms

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Journal of Mountain Science 2024年第1期21卷 322-334页

作者： QIN yanhui MA Haoyuan zhang Lele YIN Jinshuai ZHENG Xionghui LI Shuo Department of Civil Engineering Qingdao University of TechnologyQingdao 266520China Department of Geography Qinghai Normal UniversityXining 810008China

The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP.

关键词： Freeze–thaw cycles Quantification Machine learning algorithms Qinghai–Tibet Plateau Concrete

Promotion effect of FOXCUT as a microRNA sponge for miR-24-3p on progression in triple-negative breast cancer through the p38 MAPK signaling pathway

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Chinese Medical Journal 2024年第1期137卷 105-114页

作者： Xiafei Yu Fangze Qian Xiaoqiang zhang yanhui Zhu Gao He Junzhe Yang Xian Wu Yi Zhou Li Shen Xiaoyue Shi Hongfei zhang Xiao’an Liu Department of Breast Surgery The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China

Background:Triple-negative breast cancer(TNBC)is a type of highly invasive breast cancer with a poor prognosis.According to new research,long noncoding RNAs(lncRNAs)play a significant role in the progression of cancer.Although the role of lncRNAs in breast cancer has been well reported,few studies have focused on TNBC.This study aimed to explore the biological function and clinical significance of forkhead box C1 promoter upstream transcript(FOXCUT)in triple-negative breast cancer.Methods:Based on a bioinformatic analysis of the cancer genome atlas(TCGA)database,we detected that the lncRNA FOXCUT was overexpressed in TNBC tissues,which was further validated in an external cohort of tissues from the General Surgery Department of the First Affiliated Hospital of Nanjing Medical University.The functions of FOXCUT in proliferation,migration,and invasion were detected in vitro or in vivo.Luciferase assays and RNA immunoprecipitation(RIP)were performed to reveal that FOXCUT acted as a competitive endogenous RNA(ceRNA)for the microRNA miR-24-3p and consequently inhibited the degradation of p38.Results:lncRNA FOXCUT was markedly highly expressed in breast cancer,which was associated with poor prognosis in some cases.Knockdown of FOXCUT significantly inhibited cancer growth and metastasis in vitro or in vivo.Mechanistically,FOXCUT competitively bounded to miR-24-3p to prevent the degradation of p38,which might act as an oncogene in breast cancer.Conclusion:Collectively,this research revealed a novel FOXCUT/miR-24-3p/p38 axis that affected breast cancer progression and suggested that the lncRNA FOXCUT could be a diagnostic marker and therapeutic target for breast cancer.

关键词： Triple negative breast neoplasms RNA,long noncoding FOXCUT miR-24-3p p38 MAPK signaling pathway Disease progression

Direct observation of oxygen vacancy formation and migration over ceria surface by in situ environmental transmission electron microscopy

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Journal of Rare Earths 2024年第4期42卷 676-682页

作者： Dawei Pang Wei Li Ningqiang zhang Hong He Shengcheng Mao yanhui Chen Liwei Cao Chong Li Ang Li Xiaodong Han Beijing Key Laboratory of Solid Microstructure and Properties Department of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory for Green Catalysis and Separation The Faculty of Environment and LifeBeijing University of TechnologyBeijing10124China International Joint Research Laboratory for Quantum Functional Materials of Henan School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou450001China

The extremely high structural tolerance of ceria to oxygen vacancies(Ov)has made it a desirable catalytic material for the hydrocarbon oxidation to chemicals and pharmaceuticals and the reduction of gaseous pollutants.It is proposed that the formation and diffusion of Ov originate from its outstanding reduction property.However,the formation and diffusion process of Ov over the surface of ceria at the atomic level is still unknown.Herein,the structural and valence evolution of CeO_(2)(111)surfaces in reductive,oxidative and vacuum environments from room temperature up to 700℃was studied with in situ aberration-corrected environmental transmission electron microscopy(ETEM)experiments.Ov is found to form under a high vacuum at elevated temperatures;however,the surface can recover to the initial state through the adsorption of oxygen atoms in an oxygen-contained environment.Furthermore,in hydrogen environment,the step-CeO_(2)(111)surface is not stable at elevated temperatures;thus,the steps tend to be eliminated with increasing temperature.Combined with first-principles density function calculations(DFT),it is proposed that O-terminated surfaces would develop in a hypoxic environment due to the dynamic diffusion of Ov from the outer surface to the subsurface.Furthermore,in a reductive environment,H2 facilitates the formation and diffusion of Ov while Ce-terminated surfaces develope.These results reveal dynamic atomic-scale interplay between the nanoceria surface and gas,thereby providing fundamental insights into the Ov-dependent reaction of nano-CeO_(2) during catalytic processes.

关键词： Ceria Direct observation In situ ETEM Oxygen vacancy Density function calculations Rareearths

THE BOUNDARY SCHWARZ LEMMA AND THE RIGIDITY THEOREM ON REINHARDT DOMAINS B_(p)^(n) OF C^(n)

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Acta Mathematica Scientia 2024年第3期44卷 839-850页

作者：王建飞张艳慧 School of Mathematical Sciences Huaqiao UniversityQuanzhou362021China Department of Mathematics Beijing Technology and Business UniversityBeijing100048China

By introducing the Carathéodory metric,we establish the Schwarz lemma at the boundary for holomorphic self-mappings on the unit p-ball B_(p)^(n) of C^(n).Furthermore,the boundary rigidity theorem for holomorphic self-mappings defined on B_(n)^(p) is obtained.These results cover the boundary Schwarz lemma and rigidity result for holomorphic self-mappings on the unit ball for p=2,and the unit polydisk for p=∞,respectively.

关键词： Schwarz lemma Carathéodory metric rigidity

Regulation of MRI contrast and cellular retention time by cellular interfacial distribution of Gd agents:Implications for stem cell tracking

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Magnetic Resonance Letters 2022年第1期2卷 48-55,I0003页

作者： yanhui zhang Binbin Li Bo Tan Hailu zhang Zongwu Deng School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei230026China CAS Key Laboratory of Nano-Bio Interface Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesSuzhou215123China

Human mesenchymal stem cells(hMSCs)were labeled with Dotarem or(Gd-DOTA)2-EM7(EM7Gd2)via electroporation(EP).Cellular transmission electron microscopy(TEM)reveals free distribution of Gd agents and formation of EM7Gd2 clusters in the cytosol.Cellular magnetic resonance imaging(MRI)reveals that the free Gd agents induce MRI signal enhancement effect due to its fast exocytosis and subsequent interaction with intercellular water molecules.The EM7Gd2 clusters exhibits a longer intracellular retention time and induce a persistent MRI signal reduction effect.The cellular MRI results are interpreted by taking into account both T1 and T2 relaxation rates and their correlation with cellular binding structures of Dotarem and EM7Gd2.

关键词： MRI Gd agent Cellular distribution Relaxation rate Intracellular retention time