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Acta Mechanica Solida Sinica 2016年第4期29卷 391-406页

作者： Linlin Sun Miao Zhang Weiping hu qingchun Meng Institute of Solid Mechanics School of Aeronautic Science and Engineering Beihang University Institute of Manned Space System Engineering China Academy of Space Technology

To consider the anisotropic damage in fatigue, an improved boom-panel model is presented to simulate a representative volume element (RVE) in the framework of continuum damage mechanics. The anisotropic damage state of the RVE is described by the continuity extents of booms and panels, whose damage evolutions are assumed to be isotropic. The numerical implementation is proposed on the basis of damage mechanics and the finite element method. Finally, the approach is applied to the fatigue life prediction of 2A12-T4 aluminium alloy specimen under cyclic loading of tension-torsion. The results indicate a good agreement with the experimental data.

关键词： boom-panel model anisotropic damage fatigue tension-torsion life prediction

A NEW DAMAGE MECHANICS BASED APPROACH TO FATIGUE LIFE PREDICTION AND ITS ENGINEERING APPLICATION

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Acta Mechanica Solida Sinica 2015年第5期28卷 510-520页

作者： Fei Shen Weiping hu qingchun Meng Miao Zhang Institute of Solid Mechanics School of Aeronautics Science and Engineering Beihang University Institute of Manned Space System Engineering China Academy of Space Technology

An approach based on continuum damage mechanics to fatigue life prediction for structures is proposed. A new fatigue damage evolution equation is developed, in which the pa- rameters are obtained in a simple way with reference to the experimental results of fatigue tests on standard specimens. With the utilization of APDL language on the ANSYS platform, a finite element implementation is presented to perform coupling operation on damage evolution of mate- rial and stress redistribution. The fatigue lives of some notched specimens and a Pitch-change-link are predicted by using the above approach. The calculated results are validated with experimental data.

关键词： fatigue damage model damage mechanics fatigue life finite element method

二氧化氯缓释剂对低温贮藏荔枝品质及关键花青素的影响

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食品工业科技 2024年第6期45卷 297-303页

作者：郭莉吴广尹青春罗林邓浩国家市场监管重点实验室(热带果蔬质量与安全) 海南省食品检验检测中心海南海口570311 海南省热带果蔬冷链研究重点实验室海南省农业科学院农产品加工设计所海南海口571100 广东省食品质量安全重点实验室华南农业大学食品学院广东广州510640

荔枝采后易由花青素降解、呼吸代谢等导致其品质劣变,而二氧化氯(ClO2)有护色和抑制呼吸的多重作用。为探明ClO2对采后荔枝的综合影响,本研究分别采用0.1 g(T1)、0.4 g(T2)和1.2 g(T3)ClO2缓释剂处理荔枝,以0 g(CK)为对照,通过品质指标... 详细信息

荔枝采后易由花青素降解、呼吸代谢等导致其品质劣变,而二氧化氯(ClO2)有护色和抑制呼吸的多重作用。为探明ClO2对采后荔枝的综合影响,本研究分别采用0.1 g(T1)、0.4 g(T2)和1.2 g(T3)ClO2缓释剂处理荔枝,以0 g(CK)为对照,通过品质指标、色泽指标、花青素等评价其保鲜效果,并通过相关性分析探讨它们间的联系。结果表明,T1组荔枝贮藏品质最佳。贮藏7 d时,T1组荔枝可溶性固形物、a值分别比同期CK组显著(P<0.05)提高了2.93%和10.13%,而呼吸速率显著(P<0.05)降低了34.54%。与此相反,T3组荔枝第7 d相对电导率达最高值35.84%,a达降到最低值18.38,说明细胞结构破坏、漂白明显,贮藏品质最差。为进一步探明色泽变化与花青素的关系,筛选出荔枝中10种关键花青素,含7种原花青素,它们占总花青素达66.96%。相关性分析表明,在贮藏期内,T1、T2、T3组中色泽a值与矢车菊素半乳糖苷的相关系数分别为0.980、0.548、0.360,与矢车菊素-3-O-葡萄糖苷的相关系数为0.985、0.488、0.402。T1组维持了最好的色泽,可能与其维持以上2种关键红色花青素较慢分解有关,而T3组加速了花青素的分解。本研究可为提高荔枝采后品质提供参考。

关键词：荔枝 ClO2 缓释剂花青素贮藏品质相关性分析

机械振动对真空差压铸造ZL114A铝硅共晶组织及力学性能的影响

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材料工程 2024年第7期52卷 194-203页

作者：廖青春芦刚周泽远胡国友毛蒲吴晓雨陈义斯严青松南昌航空大学轻合金加工科学与技术国防重点学科实验室南昌330063 江西洪都国际机电有限责任公司南昌330024

为进一步提升复杂薄壁ZL114A铸件性能,对真空差压铸造过程施加机械振动,系统研究振幅和频率对Al-Si共晶组织及铸件拉伸性能的影响。结果表明,机械振动可以强化熔体局域对流,折断先凝固枝晶,并造成硅相碎断形成短棒状、颗粒状组织。同时... 详细信息

为进一步提升复杂薄壁ZL114A铸件性能,对真空差压铸造过程施加机械振动,系统研究振幅和频率对Al-Si共晶组织及铸件拉伸性能的影响。结果表明,机械振动可以强化熔体局域对流,折断先凝固枝晶,并造成硅相碎断形成短棒状、颗粒状组织。同时,可以促进凝固前沿溶质均匀分布,抑制硅相过度生长,诱发初生相周围Al-Si共晶网状转变。振幅和频率对合金强度和塑性的影响呈对立关系,高频低幅下近振源侧样品获得最高抗拉强度达335.6 MPa,但合金伸长率下降至1.54%。然而,由于振动能在熔体传播存在能量耗散,远振源侧样品强度仅327.06 MPa,伸长率为1.67%。此外,性能衰减拟合分析显示,增加频率有利于抑制振动能的损失,改善远侧熔体机械振动处理效果。

关键词：真空差压铸造机械振动 Al-Si共晶力学性能

中国式现代化中“人”的理解原则——基于马克思人学变革的阐释

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国家现代化建设研究 2024年第3期3卷 43-54页

作者：蔺庆春中国政法大学北京100088

在西方思想史上,“个人”主体地位的确立,是近代社会和近代哲学诞生的重要标志。马克思摒弃了近代西方哲学的“抽象的人”的传统,批判了人学的形而上学,吸收了黑格尔关于人的现实性、社会性和历史性建构的积极成果,提出了“现实的诸个... 详细信息

在西方思想史上,“个人”主体地位的确立,是近代社会和近代哲学诞生的重要标志。马克思摒弃了近代西方哲学的“抽象的人”的传统,批判了人学的形而上学,吸收了黑格尔关于人的现实性、社会性和历史性建构的积极成果,提出了“现实的诸个人”概念,并将其作为历史的起点。“现实的诸个人”概念具有世界现代文明的重要特征,对于深入把握中国式现代化与西方现代化的联系和差别具有重要意义。马克思主义的人学变革,为正确理解中国式现代化中的人及其本质提供了根本原则。中国式现代化坚持以人民为中心,立足人的自我实现和全面发展,把实现人民对美好生活的向往作为现代化建设的出发点和落脚点,强调个人与他人、个人与社会、个人与自然的和谐统一。

关键词：马克思人学中国式现代化人的现代化

从“人民民主”到“自我革命”:中国共产党回答跳出“历史周期率”的内在逻辑与话语变迁

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安康学院学报 2024年第1期36卷 23-28页

作者：汪庆春喀什大学人文学院新疆喀什844000

救亡图存是近代史主旋律,中国共产党带领人民群众取得了革命、建设事业胜利的同时,也在思考党“跳出历史周期率”的问题。毛泽东和习近平分别对中国共产党如何跳出“历史周期率”给出了明确的回答,其一为“人民民主”,其一为“自我革命... 详细信息

救亡图存是近代史主旋律,中国共产党带领人民群众取得了革命、建设事业胜利的同时,也在思考党“跳出历史周期率”的问题。毛泽东和习近平分别对中国共产党如何跳出“历史周期率”给出了明确的回答,其一为“人民民主”,其一为“自我革命”,二者存在话语表述差异,然其内在逻辑具有深刻的一致性,即中国共产党始终坚持“人民至上”理念,这是中国共产党跳出“历史周期率”的不二法宝与战略选择。“人民民主”与“自我革命”话语表述的差异性,反映了党的领袖在不同的时代背景及社会形势下,对中共争取执政并实现长期执政的探索,均与时代发展之需求契合,而其话语变迁既折射出中共应对不同形势的施政方针,也蕴含了其对“人民至上”理念的与时俱进的思考与实践。

关键词：中国共产党历史周期率人民民主自我革命话语变迁

Experimental method for and theoretical research on defect tolerance of fxed plate based on damage mechanics

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Chinese Journal of Aeronautics 2013年第5期26卷 1195-1201页

作者： Zhan Zhixin hu Weiping Zhang Miao Zhu Yuefa Meng qingchun Institute of Solid Mechanics School of Aeronautic Science and EngineeringBeiHang University Institute of Manned Space System Engineering China Academy of Space Technology Harbin Aircraft Manufacturing Company

An experimental method and a theoretical analysis based on continuum damage mechan- ics are applied for the defects tolerance of fixed plate. The defects type studied in this article is scratch, which is considered a typical defect on fixed plate according to the engineering practice. The general approach to the defects tolerance analysis of scratched fixed plate is presented. The method of fatigue life prediction for standard notched specimens has been established on the basis of continuum damage mechanics. For the purpose of obtaining the influence law of fatigue life in consequence of scratches, fatigue experiments of standard notched specimens and scratched specimens have been done. Evalu- ation of the fatigue life of scratched fixed plate has been carried out. And the value of scratch defects permissible to the condition of safety service life has been worked out. According to the results of the- oretical calculations, the fatigue experiment of scratched fixed plate has been performed. The outcome shows that the theoretical prediction tallies with the experimental results.

关键词： Damage mechanics Defect tolerance Fatigue experiment Fixed plate Life prediction

May Traditional Chinese Medicine Reduce the Risk of Developing Rheumatoid Arthritis?An One-armed Prospective Study

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Clinical Complementary Medicine and Pharmacology 2024年第1期4卷 10-18页

作者： Kaixin Gao Qi Liang Dongyun Li Chuanning Li Maojie Wang Xiumin Chen qingchun huang Zehuai Wen Per-Johan Jakobsson Runyue huang The Second Affiliated Hospital of Guangzhou University of Chinese Medicine(Guangdong Provincial Hospital of Chinese Medicine) Guangzhou 510006GuangdongChina The Second Clinical Medical College Guangzhou University of Chinese MedicineGuangzhou 510006GuangdongChina State Key Laboratory of Dampness Syndrome of Chinese Medicine The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510120GuangdongChina Guangdong Provincial Key Laboratory of Chinese Medicine for Prevention and Treatment of Refractory Chronic Diseases Guangzhou 510403GuangdongChina Guangdong-Hong Kong-Macao Joint Lab on Chinese Medicine and Immune Disease Research Guangzhou 510000GuangdongChina The key unit of methodology of clinical research The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510000GuangdongChina Rheumatology Unit Department of Medicine SolnaKarolinska InstituteKarolinska University HospitalStockholm 17177Sweden Department of Doctor-Patient Relationship The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630GuangdongChina

Background:Rheumatoid arthritis(RA)is a worldwide public health *** and prevention before the onset of rheumatic diseases is a new direction in current ***:The aim of this study was to evaluate the potential and feasibility of traditional Chinese medicine(TCM)in the prevention of ***:This was a single-armed prospective clinical *** participants were recruited from a single center in Guangdong,*** who were tested positive for anti-cyclic citrullinated peptide antibody(anti-CCP)and/or rheumatoid factor(RF),had no synovitis and never been treated with disease-modifying anti-rheumatic drugs(DMARDs),were enrolled to take the huayu-Qiangshen-Tongbi(HQT)decoction orally twice daily,200 mL each time for 24 *** outcome was the proportion of patients who met 2010 ACR(American College of Rheumatology)/EULAR(European League Against Rheumatism)classification criteria of RA during *** outcomes included levels of anti-CCP,RF,erythrocyte sedimentation rate(ESR),C-reactive protein(CRP),assessment of signs and symptoms,and radiographic progression by magnetic resonance imaging(MRI).Results:19 individuals were enrolled in the study,4 of which withdrew because of the epidemic of *** the observation period,3 individuals(20%)developed RA and they had longer morning stiffness(P=0.009)and more obvious synovial enhancement in MRI(P=0.041)at baseline when compared with those who did not develop *** 24 weeks of intervention,there were improvements in 28-swollen joint count(SJC28)(P=0.046),Visual Analog Scale(VAS)(P=0.019),Patient’s Global Assessment(PtGA)(P=0.019)and Physician’s Global Assessment(PGA)(P=0.031),but no statistical significance was observed in the levels of anti-CCP,RF,ESR,CRP,morning stiffness,28-tender joint count(TJC28),Health Assessment Questionnaire(HAQ)and magnetic resonance imaging(MRI)analysis(P>0.05).Conclusion:The HQT formula is safe and could improve joint symptoms and s

关键词： Rheumatoid arthritis(RA) Prevention Traditional Chinese medicine(TCM) huayu-Qiangshen-Tongbi decoction(HQT) Clinical trial

肿瘤坏死因子-α、超敏C反应蛋白与突发性耳聋关系的Meta分析

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中华耳科学杂志 2024年第4期22卷 638-643页

作者：米雪芹王媛玲潘庆春徐瑞张琪胡雯静李蓓川北医学院运动医学与康复学院南充637000 川北医学院附属医院耳鼻咽喉头颈外科

目的利用Meta分析方法分析肿瘤坏死因子-α(tumor necrosis factor-alpha,TNF-α)、超敏C反应蛋白(high sensitivity c-reactive protein,hs-CRP)与突发性耳聋(sudden sensorineural hearing loss,SSNHL)的关系。方法用计算机检索中国知网、万方数据、维普网、CBM、PubMed、Embase、Cochrane library、Web of Science等中英文数据库,搜集有关TNF-α、hs-CRP与SSNHL相关研究,时间范围为建库起至2022年4月。由2位独立评价者筛选文献、提取资料,采用RevMan5.3软件、Stata软件对符合质量标准的研究进行Meta分析。结果纳入16篇文献研究,SSNHL患者血清TNF-α、hs-CRP浓度均高于对照组,差异均有统计学意义(P<0.05)。结论SSNHL患者血清TNF-α、hs-CRP升高,对疾病诊疗有一定临床指导价值。

关键词：突发性耳聋炎症因子肿瘤坏死因子-α 超敏C反应蛋白 Meta分析

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Matlab软件在教学实验中的应用

集成电路应用 2024年第6期41卷 244-245页

作者：朱青春大同煤炭职业技术学院山西037003

阐述Matlab在数值计算、数据分析、图形可视化和模拟仿真等方面的应用策略,探讨Matlab在创新性实验设计、科技竞赛项目开发、校企合作项目创新实践中的应用前景。

关键词：教学软件模拟分析数值计算 Matlab