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贺根山缝合带南侧西乌旗哈尔敖包早石炭世二长花岗岩的发现及其构造意义

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地质科学 2024年第4期59卷 907-924页

作者：程天赦杨文静张学斌滕超杨欣杰来林吴荣泽周长红中国地质调查局自然资源实物地质资料中心河北廊坊065201 天津市地质调查研究院天津300191

内蒙古西乌旗地区新发现的哈尔敖包二长花岗岩体出露于贺根山缝合带南侧,厘定该岩体的形成时代、岩石成因和构造环境对探讨古亚洲洋贺根山洋盆的构造演化具有重要意义。哈尔敖包二长花岗岩LA-ICP-MS锆石U-Pb测年结果为327.7±2.6 Ma,形... 详细信息

内蒙古西乌旗地区新发现的哈尔敖包二长花岗岩体出露于贺根山缝合带南侧,厘定该岩体的形成时代、岩石成因和构造环境对探讨古亚洲洋贺根山洋盆的构造演化具有重要意义。哈尔敖包二长花岗岩LA-ICP-MS锆石U-Pb测年结果为327.7±2.6 Ma,形成于早石炭世,并非前人推测的中二叠世;岩石富硅(SiO_(2)平均值为76.04%)、碱(K_(2)O+Na_(2)O平均值为8.82%)、铝(Al_(2)O_(3)平均值为13.44%)及Rb、Pb、Th、U、Ta、LREE,低镁、铁、锰、钙、钛、磷(P_(2)O_(5)平均值为0.03%)及Sr、Eu、Nb、Ti、HREE,铕负异常较明显(δEu平均值为0.30)。岩石地球化学研究表明,哈尔敖包二长花岗岩显示Ⅰ型花岗岩特征,形成于同碰撞向后造山转换阶段的初始伸展构造环境,Zr/Hf、Nb/Ta比值及岩石分异指数(DI=94.93~96.81)显示岩浆在侵位过程中经历了较强的分异演化。结合区域研究成果,哈尔敖包早石炭世二长花岗岩体的识别与确定,表明西伯利亚板块南缘与锡林浩特微陆块可能在早石炭世早期发生了短暂碰撞造山作用,标示着古亚洲洋贺根山洋盆在早石炭世早期短暂性闭合后,于早石炭世晚期又快速打开并进入俯冲消减阶段,呈现出多旋回演化的特征。

关键词：二长花岗岩 Ⅰ型花岗岩早石炭世贺根山洋盆多旋回演化贺根山缝合带

One-step uniform growth of magnesium hydride nanoparticles on graphene

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Progress in Natural Science:Materials International 2017年第1期27卷 81-87页

作者： Yuqin Huang Guanglin Xia Jie Chen Baoping Zhang Qian Li xuebin Yu Department of Materials Science Fudan University State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering Shanghai University Materials Genome institute Shanghai University

A simple solvent-free method to synthesize MgH;nanoparticles（MgH;NPs） uniformly grown on graphene nanosheets（GNs） has been reported in this paper. Based on the formation of MgH;by di-n-butylmagnesium(（C;H;）;Mg) thermal decomposition under hydrogen pressure, the GNs were added as matrix to hinder the agglomeration and growing of MgH;NPs. The fabricated MgH;/GNs nanocomposites, in which MgH;NPs were homogenously growing in the graphene matrix, have been synthesized by the favorable adsorption energy between（C;H;）;Mg and GNs. Resulting from the one-step solvent-free route, the generated MgH;NPs shows high hydrogen capacity and steady hydriding and dehydriding properties, without the interference of the synthetic medium. At the same time, the size of the fabricated MgH;NPs can be controlled by adjusting the mass ratio of MgH;to graphene, the various hydrogen pressure and temperature. Attributed to smaller size effect, well uniform distribution of high density MgH;NPs, and the agglomeration blocking ability of graphene,the MgH;/GNs-40 wt% exhibits the favorite hydrogen storage performance.

关键词： Hydrogen storage Magnesium hydride Graphene Nanoparticles Nanocomposite

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阻尼减振技术在推进轴系试验中的应用分析

噪声与振动控制 2024年第5期44卷 255-260页

作者：周兆华田佳彬雷晓薇王刚伟张雪冰王隽武汉第二船舶设计研究所武汉430064

推进器转子的激励力会通过轴系及艇体产生辐射噪声。阻尼减振是系统振动控制与优化中的一种重要手段,其本质是消耗振源传递的能量,进而降低结构振动响应。搭建轴系试验台架,以轴系振动加速度总值级为评价指标,分析加装颗粒阻尼吸振器和... 详细信息

推进器转子的激励力会通过轴系及艇体产生辐射噪声。阻尼减振是系统振动控制与优化中的一种重要手段,其本质是消耗振源传递的能量,进而降低结构振动响应。搭建轴系试验台架,以轴系振动加速度总值级为评价指标,分析加装颗粒阻尼吸振器和换装具有黏弹特性的高锰基合金材料基座的减振效果。试验结果表明这两种基于阻尼的减振方案对推进轴系均有一定的减振效果,可为推进器振动噪声控制提供技术支撑。

关键词：振动与波颗粒阻尼高锰基合金轴系试验

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一种压电驱动单屏蔽电极3维电场传感芯片

电子与信息学报 2024年第4期46卷 1513-1520页

作者：彭思敏夏善红刘向明高雅浩张洲威张巍邢学斌刘语斐毋正伟彭春荣中国科学院空天信息创新研究院传感技术联合国家重点实验室北京100190 中国科学院大学电子电气与通信工程学院北京100049

为降低激励电压和串扰噪声,实现高灵敏3维电场检测,该文提出一种压电驱动单屏蔽电极3维电场传感芯片。其敏感结构由1组可动屏蔽电极和4组固定感应电极构成,固定感应电极两两对称,在压电驱动结构作用下可动屏蔽电极垂直振动,4组感应电极... 详细信息

为降低激励电压和串扰噪声,实现高灵敏3维电场检测,该文提出一种压电驱动单屏蔽电极3维电场传感芯片。其敏感结构由1组可动屏蔽电极和4组固定感应电极构成,固定感应电极两两对称,在压电驱动结构作用下可动屏蔽电极垂直振动,4组感应电极在待测电场作用下产生周期性的感应电流,通过测量4组感应电极的感应电流,并经过差分求和解耦方法可分别获得x,y,z坐标轴方向的电场分量。该文通过有限元仿真设计了3维电场传感芯片结构,分析了其测量的可行性,对关键结构参数进行优化设计,并设计了敏感芯片加工工艺流程。对研制的芯片进行了实验测试,结果表明,单屏蔽电极3维电场传感芯片在0~50 kV/m电场强度范围内,x,y,z 3轴输出灵敏度分别为0.2214 mV/(kV/m),0.3580 mV/(kV/m),2.1768 mV/(kV/m),3维电场的最大测量误差小于5.3%。

关键词：单屏蔽电极 3维电场垂直振动

各向异性屈服模型对酸洗钢板拉深成形模拟结果的影响

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机械工程材料 2024年第10期48卷 105-109页

作者：鄂宏伟李亚东郑学斌李学涛胡开广首钢集团有限公司技术研究院北京100043

采用Autoform软件分别基于Hill'48,Barlat'89和BBC-2005各向异性屈服模型对SRTC1酸洗钢板拉深成形进行有限元模拟,通过制耳高度和厚度分布数值模拟与试验结果的对比,研究了屈服模型对酸洗钢板拉深成形模拟的影响,获得了最佳屈服模型。... 详细信息

采用Autoform软件分别基于Hill'48,Barlat'89和BBC-2005各向异性屈服模型对SRTC1酸洗钢板拉深成形进行有限元模拟,通过制耳高度和厚度分布数值模拟与试验结果的对比,研究了屈服模型对酸洗钢板拉深成形模拟的影响,获得了最佳屈服模型。结果表明:采用Hill'48,Barlat'89和BBC-2005屈服模型模拟的钢板拉深成形筒形件制耳高度差与试验结果的相对误差分别为16.20%,11.27%,7.74%,厚度最大差值模拟结果与试验结果的相对误差分别为8.28%,5.25%,2.30%。BBC-2005屈服模型综合考虑了材料应力和变形各向异性参量,在制耳高度和厚度分布方面均最有最高的预测精度。

关键词：拉深成形各向异性屈服模型数值模拟

模拟宿主防御肽的聚(2-噁唑啉)作为佐剂增强多粘菌素B的抗菌活性并拓展抗菌谱

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Science china Materials 2024年第3期67卷 991-999页

作者：罗政杰赵学斌周敏邹景橙肖希勉刘龙强谢佳洋武月铭张雯静刘润辉 State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237China Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Key Laboratory for Ultrafine Materials of Ministry of EducationFrontiers Science Center for Materiobiology and Dynamic ChemistryResearch Center for Biomedical Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Department of Orthopedic Surgery Shanghai General HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200080China

临床上常用的广谱抗生素无法有效解决抗生素高度耐药ESKAPE菌感染的难题,ESKAPE耐药菌已经成为人类生命健康的重大威胁.抗生素与佐剂的联合治疗是解决抗生素耐药菌感染的重要途径,但是探索对所有ESKAPE耐药菌都具有广谱和高效抗菌活性... 详细信息

临床上常用的广谱抗生素无法有效解决抗生素高度耐药ESKAPE菌感染的难题,ESKAPE耐药菌已经成为人类生命健康的重大威胁.抗生素与佐剂的联合治疗是解决抗生素耐药菌感染的重要途径,但是探索对所有ESKAPE耐药菌都具有广谱和高效抗菌活性的抗生素-佐剂组合仍然面临巨大挑战.在这里,我们提出了一种抗生素-佐剂的有效设计策略,将对ESKAPE中耐药阴性菌具有高活性的多粘菌素B(PMB)与模拟宿主防御肽的细菌膜靶向阳离子聚(2-噁唑啉)相结合.我们通过2-噁唑啉单体可控聚合,合成了一系列具有不同疏水性侧链的阳离子聚(2-噁唑啉).研究表明,聚(2-噁唑啉)和PMB的组合效果随着聚(2-噁唑啉)侧链疏水性的提高呈现出从拮抗效应到协同效应的逐渐变化.其中,优选的聚(2-噁唑啉)EACA-POX_(20)显著增强了PMB的抗菌活性,尤其是对于ESKAPE耐药阳性菌的抗菌活性增强了16–32倍.聚(2-噁唑啉)EACA-POX_(20)有效增强了PMB的抗菌活性并扩展了PMB的抗菌谱.聚(2-噁唑啉)和PMB的组合策略能够有效对抗所有耐药ESKAPE病原体,为解决ESKAPE耐药菌提供了新的思路.

关键词： poly(2-oxazoline)s ESKAPE bacteria polymyxin B broad-spectrum activity

Transparent conducting CuCr1-xMgxO2 films prepared by pulsed laser deposition

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Transparent conducting CuCr1-xMgxO2 films prepared by pulsed...

基于卷积和长短期记忆网络的地浸开采铀浓度预测研究

2007亚洲光电子会议材料的激光加工与制造分会场

作者： Da Lia, Xiaodong Fang*a, Ruhua Taoa, Weiwei Donga, Zanhong Denga, xuebin Zhub aAnhui institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei230031, P. R.china bKey Laboratory of Materials Physics, institute of Solid State Physics, ChineseAcademy of Sciences, Hefei 230031, P.R. china

Transparent conducting CuCr1-xMgxO2 thin films were prepared by pulsed laser deposition （PLD） from polycrystalline CuCr1-xMgxO2 targets. The derived CuCr1-xMgxO2 films were highly c-axis oriented deposited at higher substrate temperature. The micro structural, electrical as well as optical properties were studied. It was found that the films were relatively smooth, and behaved as semiconductors. The transmittances of the films in the visible region are about 80% with direct band gaps about 3.15eV. The results suggested that CuCr1-xMgxO2 films could be successfully prepared by PLD, which can broaden the applications of the transparent conducting oxides films.

关键词： transparent conducting oxides delafossite pulsed laser deposition

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铀矿地质 2024年第3期40卷 578-586页

作者：贾明滔谭笑苏学斌陈梅芳鲁芳中南大学资源与安全工程学院湖南长沙410083 中国铀业有限公司北京100013 核工业北京化工冶金研究院北京101100 湖南女子学院湖南长沙410083

文章通过集成经验模态分解(Empirical Mode Decomposition,EMD)、卷积神经网络(Convolutional Neural Networks,CNN)、长短期记忆网络(Long Short-Term Memory,LSTM)、傅里叶变换,提出了一种新型地浸单元浸出液铀浓度预测方法。该方法将浸出液铀浓度监测值时间序列使用EMD进行分解,分解为趋势项、周期项和随机项。通过构建CNN+LSTM网络,并结合傅里叶变换和多项式拟合对铀浓度趋势项、周期项和随机项进行预测,3者预测之和作为铀浓度预测结果。实证结果表明:EMD能够有效分解铀浓度时间序列,模型拟合度比未进行EMD分解的模型提升超50%;基于EMD、CNN+LSTM和傅里叶变换的集成方法预测精度良好,预测的平均绝对百分比误差(Mean Absolute Percentage Error,MAPE)为0.348,与LSTM、反向传播(Back Propagation,BP)和门控循环网络(Gate Recurrent Unit,GRU)等模型相比最高提升超80%。文章提出的集成方法能够准确预测浸采单元铀浓度变化,解决了原有方法和模型无法对非线性、非平稳铀浓度序列进行准确预测的问题,从而为地浸矿山生产规划提供技术支持,并有助于提升中国铀矿山的数字化、信息化程度。

关键词：铀浓度预测经验模态分解卷积神经网络长短期记忆傅里叶变换

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Life-history dependent relationships between plasma alkaline phosphatase activity and body condition in male Eurasian Tree Sparrows

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Avian Research 2017年第3期8卷 163-167页

作者： Yuliang Zhao Lingjuan Gong Baohua Zhao xuebin Gao Yuefeng Wu Dongming Li Key Laboratory of Animal Physiology Biochemistry and Molecular Biology of Hebei Province College of Life Sciences Hebei Normal University Shaanxi institute of Zoology

Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences have shown that body mass, size-corrected mass(SCM), and hematocrit(Hct) could be used as estimates of the energetic state of individuals to illustrate life-history trade-offs and individual quality in field physiology. Plasma alkaline phosphatase(ALP) plays critical roles in regulating the metabolism of energy but very limited information is known on its link with body mass or ***: We determined the changes of plasma ALP levels in both early breeding and wintering stages of male Eurasian Tree Sparrows(Passer montanus), and examined the relationships between ALP and body mass, SCM, and Hct of the ***: Our study showed that(1) in male Eurasian Tree Sparrows, body mass did not vary with life-history stage but plasma ALP activity significantly increased in the wintering stage compared to the breeding stage;(2) ALP activity was not correlated with individual body mass but was positively correlated with individual SCM and Hct. Such positive correlations, however, only occurred in the wintering but not in the breeding ***: Our results suggest that plasma ALP activities in free-living birds can be used as one of the indicators o body condition or nutritional status for analyzing individual variation in the wintering but not in the breeding stages. The life-history dependent relationships between plasma ALP activity and body condition may contribute to our better understanding of the trade-off between individual survival and reproduction in free-living animals.

关键词： Alkaline phosphatase Size-corrected mass Hematocrit Passer montanus Life history Trade-off