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正交异性钢桥面板声发射波三维谱元法模拟及损伤定位

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应用声学 2024年第2期43卷 404-414页

作者：李丹胡晨迅贺文宇合肥工业大学土木与水利工程学院合肥230009 东南大学土木工程学院南京211189

针对大跨度桥梁正交异性钢桥面板的疲劳损伤评估与结构健康监测需求,开展基于声发射波场谱元法模拟的大型复杂板类结构损伤定位研究。采用Legendre高阶插值三维时域谱元法模拟声发射波在正交异性钢桥面板中的传播过程,验证了其内部显著... 详细信息

针对大跨度桥梁正交异性钢桥面板的疲劳损伤评估与结构健康监测需求,开展基于声发射波场谱元法模拟的大型复杂板类结构损伤定位研究。采用Legendre高阶插值三维时域谱元法模拟声发射波在正交异性钢桥面板中的传播过程,验证了其内部显著的反射、衍射和频散现象,并代替人工预断铅实测试验获得大量声发射数据。然后,利用赤池信息准则判定声发射波到达各传感器的时间,通过高斯过程回归建立到达时差与声发射源位置的关系模型,用于未知损伤的定位监测。数值模型实验结果表明,赤池信息准则和高斯过程回归改进的时差图法在正交异性钢桥面板中的平均定位误差为37.3 mm(25 dB信噪比工况),平板的定位精度高于U肋。谱元法模拟有望代替繁琐的预断铅实测试验,提升声发射时差图系列损伤定位方法的实用性。

关键词：正交异性钢桥面板损伤定位声发射波谱元法时差图法

全黄铜矿CuGaSe_(2)/CuInSe_(2)两端叠层太阳能电池的顶端设计与优化

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物理学报 2024年第10期73卷 72-87页

作者：钟建成张笑天林常青薛阳唐欢黄丹广西大学物理科学与工程技术学院南宁530004 桂林电子科技大学广西精密导航技术与应用重点实验室桂林541004

近年来单结太阳能电池的光电转换效率逐步提高,但其最高效率受到Shockley-Queisser (SQ)极限的限制.为了超越SQ极限,学者们提出了叠层太阳能电池.本工作结合第一性原理计算和SCAPS-1D器件模拟对黄铜矿化合物CuGaSe_(2)/CuInSe_(2)叠层... 详细信息

近年来单结太阳能电池的光电转换效率逐步提高,但其最高效率受到Shockley-Queisser (SQ)极限的限制.为了超越SQ极限,学者们提出了叠层太阳能电池.本工作结合第一性原理计算和SCAPS-1D器件模拟对黄铜矿化合物CuGaSe_(2)/CuInSe_(2)叠层太阳能电池进行了系统的理论研究.首先通过第一性原理计算获取了CuGaSe_(2) (CGS)的微观电子结构、缺陷特性及对应的宏观性能参数,作为后续器件模拟CGS太阳能电池的输入参数.随后采用SCAPS-1D软件分别对单结CGS与CuInSe_(2) (CIS)太阳能电池进行了仿真模拟.单结CIS太阳能电池的模拟结果与实验值具有良好的一致性.对单结CGS电池而言,在短路电流(j.(sc))最高的生长环境下进一步模拟发现,将电子传输层(ETL)换为ZnSe后可提高CGS太阳能电池的开路电压(V_(oc))和PCE.最后,将优化后的CGS与CIS太阳能电池进行了两端(2T)单片串联的器件模拟,结果显示在生长环境为富Cu、富Ga、贫Se,生长温度为700 K时,2T单片CGS/CIS叠层太阳能电池的PCE最高为28.91%,高于当前最高的单结太阳能电池效率,展现出良好的应用前景.

关键词：第一性原理计算 SCAPS-1D p型吸收层材料CuGaSe_(2) 叠层太阳能电池

原花青素对大鼠运动性心肌损伤的保护作用及机制研究

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天然产物研究与开发 2024年第8期36卷 1401-1408,1338页

作者：任鹏林丹丹聂煜王一峰董诗稳王博源玉溪师范学院体育学院玉溪653100 云南农业大学云南财经大学昆明650500 长春科技学院军事体育部长春130600

该文研究了原花青素(oligomeric proanthocyanidins,OP)对长时间、大强度运动导致的心肌损伤的保护作用及其潜在机制。Wistar大鼠进行连续6周过量游泳运动训练,其中2组大鼠每天分别灌胃50 mg/kg OP(OP50组)和100 mg/kg OP(OP100组),模型... 详细信息

该文研究了原花青素(oligomeric proanthocyanidins,OP)对长时间、大强度运动导致的心肌损伤的保护作用及其潜在机制。Wistar大鼠进行连续6周过量游泳运动训练,其中2组大鼠每天分别灌胃50 mg/kg OP(OP50组)和100 mg/kg OP(OP100组),模型组(model,Mod)灌胃等体积生理盐水,正常组(normal,Nor)作为对照。结果表明,Mod组血清中运动性心肌损伤标记物乳酸脱氢酶(lactate dehydrogenase,LDH)、肌酸激酶(creatine kinase,CK)及心肌肌钙蛋白I(cardiac troponin,cTnI)显著升高,心肌组织出现明显病理形态,呈现明显炎性细胞浸润;OP50及OP100组中LDH、CK及cTnI显著下调,心肌组织病理变化明显减轻(P<0.05)。心肌组织中,Mod组丙二醛(malondialdehyde,MDA)明显上升,抗氧化物酶谷胱甘肽(glutathione,GSH)及超氧化物歧化酶(superoxide dismutase,SOD)下降,核因子E2相关因子2(nuclear factor erythroid-2 related factor 2,Nrf2)/血红素加氧酶-1(hemeoxygenase-1,HO-1)(Nrf2/HO-1)抗氧化应激信号通路中关键蛋白的表达量显著下降;OP50及OP100组中MDA含量显著下调,GSH及SOD显著上调,Nrf2/HO-1通路中蛋白表达量显著增多(P<0.05)。Mod组血清及心肌中炎症指标肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-6(interleukin-6,IL-6)和白细胞介素-1β(interleukin-1β,IL-1β)含量明显上升,硫氧还蛋白互作蛋白/NOD样受体热蛋白结构域相关蛋白3(thioredoxin-interacting protein/NOD-like receptor thermal protein domain associated protein 3,TXNIP/NLRP3)炎症反应信号通路中关键蛋白的表达量显著上升;OP50及OP100组中炎症因子含量均显著下调,OP100组中TXNIP/NLRP3通路中蛋白表达量显著降低(P<0.05)。综上所述,补充OP对大鼠运动性心肌损伤具有明显的保护作用,且这种保护机制与增强心肌Nrf2/HO-1抗氧化通路及抑制TXNIP/NLRP3炎症反应信号通路有关。

关键词：原花青素运动性心肌损伤氧化应激 Nrf2/HO-1抗氧化通路炎症反应 TXNIP/NLRP3促炎通路

Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study

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World j.urnal of Gastrointestinal Surgery 2024年第9期16卷 2860-2869页

作者： Wen-Yu Huang Sheng Zheng dan Zhu Ying-Lang Zeng j.an Yang Xue-Li Zeng Pei Liu Shun-Ling Zhang Ming Yuan Zhi-Xia Wang Department of Tumor and Vascular Interventional Therapy Xiamen Humanity HospitalXiamen 361000Fujian ProvinceChina Department of Gastroenterology The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Medical Imaging Center Qian Wei Hospital of Jilin ProvinceChangchun 130000Jilin ProvinceChina Department of Science and Education The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Graduate School of Clinical Medicine Dali UniversityDali 671000Yunnan ProvinceChina Department of Hepatobiliary Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Department of Oncology The Affiliated Shuyang Hospital of Xuzhou Medical UniversitySuqian 223600Jiangsu ProvinceChina

BACKGROUND Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high incidence *** a common local treatment,RFA has attracted much attention for its efficacy and influence on liver *** To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by *** The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and j.ne 2023 were *** chi-square test was used to compare the data between *** Kaplan-Meier method and Cox regression were used to analyze the associ-ations between serum ALP and GGT levels and overall survival,progression-free survival(PFS)and clinical characteristics of patients before *** The 1-year survival rates of patients with normal(≤135 U/L)and abnormal(>135 U/L)serum ALP before treatment were 91%and 79%,respectively;the 2-year survival rates were 90%and 68%,respectively;and the 5-year survival rates were 35%and 18%,*** difference between the two groups was statistically significant(P=0.01).Before treatment,the 1-year survival rates of patients with normal serum GGT levels(≤45 U/L)and abnormal serum GGT levels(>45 U/L)were 95%and 87%,the 2-year survival rates were 85%and 71%,and the 5-year survival rates were 37%and 21%,*** difference between the two groups was statist-ically significant(P<0.001).Serum ALP[hazard ratio(HR)=1.766,95%confidence interval(95%CI):1.068-2.921,P=0.027]and GGT(HR=2.312,95%CI:1.367-3.912,P=0.002)is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic *** 1-year PFS rates were 72%and 50%,the 2-year PFS rates were 52%and 21%,and the 5-year PFS rates were 14%and 3%,*** difference between the

关键词： Alkaline phosphatase γ-glutamyltransferase Radiofrequency ablation Primary liver cancer Retrospective study

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高燃烧效率含卤氧化剂包覆硼粉的制备及性能

含能材料 2024年第10期32卷 1068-1079页

作者：刘睿杨丹锋张云龙聂洪奇严启龙西北工业大学固体推进全国重点实验室陕西西安710072

为了提升硼粉的点火燃烧性能,采用高能球磨与喷雾干燥相结合的技术制备了4种微纳米B-Fe-Bi_(2)O_(3)@AP/PVDF复合物,根据其高热值和高燃烧效率的特点将四种复合物命名为μBHH_c、μBHC_(e)、nBHH_(c)及nBHC_(e),并对其形貌结构、热反应... 详细信息

为了提升硼粉的点火燃烧性能,采用高能球磨与喷雾干燥相结合的技术制备了4种微纳米B-Fe-Bi_(2)O_(3)@AP/PVDF复合物,根据其高热值和高燃烧效率的特点将四种复合物命名为μBHH_c、μBHC_(e)、nBHH_(c)及nBHC_(e),并对其形貌结构、热反应性、点火延迟、质量燃速和凝聚相产物进行了表征分析。结果表明,μBHH_(c)和μBHC_(e)复合物在氩气中最大热值达9.7 k j.g~(-1),最高燃烧效率达66.2%;在氧气中最大热值达14.6 k j.g^(-1),最高燃烧效率达93.3%,空气中氧化峰温在750~760℃之间。n BHH_c和n BHC_e复合物在氩气中最大热值达9.9 k j.g~(-1),最高燃烧效率达68.9%;在氧气中最大热值达14.8 k j.g^(-1),最高燃烧效率达97.2%,空气中氧化峰温在595~600℃之间。各类复合物的最高燃烧温度达1954~2011℃,其中n BHH_(c)复合物的点火延迟最短(26 ms),且质量燃速最高(1.84 g·s^(-1));μBHC_(e)复合物的点火延迟最长(39 ms),质量燃速也最低(0.80 g·s^(-1))。各类复合物燃烧产物主要由B_(2)O_(3)、B_(4)C及少量未完全燃烧的硼组成,形貌包含5~10μm的球体及10~20μm的片状物质。

关键词：改性硼粉表界面修饰氧化剂/燃料一体化设计点火燃烧性能

Probabilistic description of extreme oscillations and reliability analysis in rolling motion under stochastic excitation

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中国科学:技术科学英文版 2023年第9期66卷 2586-2596页

作者： ZHAO dan LI YongGe XU Yong LIU Qi KURTHS j.rgen School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710072China MOE Key Laboratory for Complexity Science in Aerospace Northwestern Polytechnical UniversityXi’an 710072China Potsdam Institute for Climate Impact Research Potsdam 14412Germany Department of Physics Humboldt University BerlinBerlin 12489Germany

Large-amplitude rolling motions, also regarded as extreme oscillations, are a great threat to marine navigation, which may lead to capsizing in ship motion. Therefore, it is important to quantify extreme oscillations, assess reliability of ship systems, and establish a suitable indicator to characterize extreme oscillations in ship systems. In this work, extreme events are investigated in a ship model considering a complex ocean environment, described by a single-degree-of-freedom nonlinear system with stochastic harmonic excitation and colored Gaussian noise. The stationary probability density function(PDF) of the system is derived through a probabilistic decomposition-synthesis method. Based on this, we infer the classical damage rate of the system. Furthermore, a new indicator, independent of the PDF, is proposed to quantify the damage related only to the fourth-order moment of the system and the threshold for extreme events. It is more universal and easier to determine as compared with the classical damage rate. A large damping ratio, a large noise intensity, or a short correlation time can reduce the damage rate and the value of the *** findings provide new insights and theoretical guidance to avoid extreme oscillations and assess the reliability of practical ship movements.

关键词： rolling motion colored noise extreme oscillations reliability probabilistic decomposition-synthesis method

The system capacity view of aging and longevity

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Frontiers of Electrical and Electronic Engineering in China 2017年第3期5卷 251-259页

作者： j.ng-Dong j. Han Lei Hou Na Sun Chi Xu j.seph McDermott dan Wang Key Laboratory of Computational Biology CAS Center for Excellence in Molecular Cell Science Collaborative Innovation Center for Genetics and Developmental Biology Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

Background： Aging is a complex systems level problem that needs a systems level solution. However, system models of aging and longevity, although urgently needed, are still lacking, largely due to the paucity of conceptual frameworks for modeling such a complex process. Results： We propose that aging can be viewed as a decline in system capacity, defined as the maximum level of output that a system produces to fulfill demands. Classical aging hallmarks and anti-aging strategies can be well-aligned to system capacity. Genetic variants responsible for lifespan variation across individuals or species can also be explained by their roles in system capacity. We further propose promising directions to develop systems approaches to modulate system capacity and thus extend both healthspan and lifespan. Conclusions： The system capacity model of aging provides an opportunity to examine aging at the systems level. This model predicts that the extent to which aging can be modulated is normally limited by the upper bound of the system capacity of a species. Within such a boundary, aging can be delayed by moderately increasing an individual＇s system capacity. Beyond such a boundary, increasing the upper bound is required, which is not unrealistic given the unlimited potential of regenerative medicine in the future, but it requires increasing the capacity of the whole system instead of only part of it.

关键词： systems system capacity aging longevity

一流课程背景下基于OBE的中医药院校数据库课程混合式教学研究

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中国中医药现代远程教育 2024年第15期22卷 206-206,I0001,F0004页

作者：郭小磊李丹山西中医药大学健康服务与管理学院山西太原030024

高校要着力巩固“专业以课程为本、教师以教学为本、学生以学习为本”等3个根本地位,按照“固本培元,守正创新”的工作思路,推进本科教育高质量发展。数据库系统原理是面向信管专业的核心课程,也是中医药院校其他医学类专业的选修课程,... 详细信息

高校要着力巩固“专业以课程为本、教师以教学为本、学生以学习为本”等3个根本地位,按照“固本培元,守正创新”的工作思路,推进本科教育高质量发展。数据库系统原理是面向信管专业的核心课程,也是中医药院校其他医学类专业的选修课程,存在课时不足、成果导向不明显等问题。研究采用OBE理念,从教学目标、教学模式、教学内容和评价手段方面进行改革,做到“思政与专业、线上与线下、理论与实践、过程与效果”4个融合。

关键词：数据库系统原理 OBE理念一流课程产教融合中医药特色数据库

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化学镀镍硼镀层的研究进展

表面技术 2024年第14期53卷 32-44页

作者：张雅鑫袁炜刘圆敬黄雄刘丹单大勇广州大学物理与材料科学学院广州510006 广东腐蚀科学与技术创新研究院广州510530 中国核电工程有限公司北京400840

化学镀镍硼镀层是通过化学镀的表面处理方法在基材表面沉积的一种镍硼合金层。对近20年化学镀以及镍硼镀层的文章发表情况进行了统计,介绍了典型镍硼镀层的沉积过程和不同还原剂下的沉积原理,探讨了还原剂与硼含量对工艺和性能的影响。... 详细信息

化学镀镍硼镀层是通过化学镀的表面处理方法在基材表面沉积的一种镍硼合金层。对近20年化学镀以及镍硼镀层的文章发表情况进行了统计,介绍了典型镍硼镀层的沉积过程和不同还原剂下的沉积原理,探讨了还原剂与硼含量对工艺和性能的影响。相比传统制备工艺,如今镍硼镀层的工艺研究有了许多新的进展。近些年来,通过对绿色环保的新型稳定剂和无稳定剂镀液体系的探索、加速剂和表面活性剂的合理使用、等离子体氮化等后处理方法的应用、多层镀层与复合镀层以及三元合金镀层的深入探索,化学镀镍硼的工艺研究发展迅速,其应用范围也在原本对耐磨、耐腐蚀性能需求较高的传统领域之外,拓展出了电子工业、特种材料工业等新兴领域。目前,在化学镀镍的所有镀层中,镍硼镀层的硬度最高,除这些传统性能外,镍硼镀层还具有高反射率、低电阻率和优秀的磁性能。综述了化学镀镍硼镀层在基础理论研究、工艺研究、性能及应用研究3个方面的成果与进展,指出了未来镍硼镀层的再处理再循环工艺、工业化、原料成本等在环保、技术、经济方面可能遇到的一些机遇、挑战和有待改善之处,展望了未来镍硼镀层研究的关注重点和发展趋势。

关键词：化学镀镍硼合金文献综述工艺研究性能应用