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Water characteristics of abyssal and hadal zones in the southern Yap Trench observed with the submersible Jiaolong

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Journal of Oceanology and Limnology 2020年第3期38卷 593-605页

作者： liu Xuehai liu yongzhi CAO Wei SUN Chengjun First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China

Using observations in an applied cruise of the submersible Jiaolong,water characteristics,geostrophic transport,and turbulent mixing in abyssal and hadal zones of the southern Yap Trench were studied.The spatial structures of deep water show that the abyssal water is cold,saline,and oxygen rich.The hadal water has very small changes in potential temperature and potential density,and a little decrease in salinity and obvious decrease in oxygen.The isotherm,isopycnal,and isohaline are depressed in abyss over the central trench.The turbulent mixing is enhanced in the near-bottom zone and the hadal water on the trench slope,especially at the steep slope,the dissipation rate and diffusivity is strong,which weakens the stratification.The geostrophic flows move southward in the western region of the trench and northward in the eastern region,indicating cyclonic circulation.In the central region of the trench,the water transport is^1.74 Sv southward.In the hadal zone,the northward and southward transports are balanced.Our analysis suggests that the abyssal water in the southern Yap Trench is from Lower Circumpolar Water(LCPW)and the hadal water seems to be of the isolated local water rather than LCPW.

关键词： Yap Trench abyssal and hadal the submersible Jiaolong diapycnal mixing geostrophic flows

CONSTRUCTION OF SOLUTION FOR EVOLUTION EQUATION x_(ttt)+iCx=f

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Applied Mathematics(A Journal of Chinese Universities) 2006年第1期21卷 41-44页

作者： Zhang Lixun liu yongzhi Wang Kangning School of Optic-electronic Information UESTC Chengdu 610054 China School of Applied Mathematics UESTC Chengdu 610054 China

The construction of solution for three-order evolution equation xttt=A^3x is skillfully obtained and the semigroup of equation operator is theoretically proved,then the solution for three-order evolution equation xttt＋iCx=f is constructed from the appropriate transformation, and the necessary and sufficient conditions of its unitary semigroup are presented.

关键词： Hilbert space,generating operator,semigroup.

Cooling mechanism of embankment with block stone interlayer in Qinghai-Tibet railway

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Science China(Technological Sciences) 2007年第3期50卷 319-328页

作者： WU QingBai CHENG HongBin JIANG GuanLi MA Wei liu yongzhi State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China

In order to study the cooling mechanism of embankment with block stone interlayer under open and closed conditions,an experimental railway section was built and data within one freeze-thaw cycle were collected. The results explain well the cooling mechanism of embankment with block stone interlayer. Under the open condition in cold seasons,the enforced convection effect occurs within block stone interlayer when the wind speed is large;however,the weak air convection occurs within the block stone interlayer near the bottom of the embankment when the wind speed is slow. Under the open condition in warm seasons,heat conduc-tion occurs within block stone interlayer due to the change in wind speed and di-rection. Under the closed condition,however,the enforced convection within block stone interlayer is so weak that heat conduction is dominant in the whole year be-cause wind is blocked. Therefore,the cooling effect of embankment with a block stone interlayer to the soil beneath it is produced by enforced convection and weak free air convection;both its process and the cooling intensity are controlled by the local wind speed and direction. Because of the difference in the cooling effects,the soil temperature beneath the embankment has a temperature difference of 2℃―4℃ between the open and closed conditions.

关键词： Qinghai-Tibet railway embankment with block stone interlayer cooling mechanism enforced convection effect

Research on stability and Hopf bifurcation of marine ecosystem dynamics models

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Acta Oceanologica Sinica 2016年第4期35卷 124-131页

作者： SHI Honghua HU Long FANG Guohong WEI Zexun SHEN Chengcheng liu yongzhi First Institute of Oceanography State Oceanic Administration School of Mathematics Shandong University College of Environmental Science and Engineering Ocean University of China Key Laboratory of Physical Oceanography Ocean University of China

The predictability of marine ecosystem dynamics models is one of the most vital factors to limit their practical applications, of which the stability is the fundamental condition. In order to discuss the stability and Hopf bifurcation of marine ecosystem dynamics models, an approach based on a theorem termed dimension reduction was proposed and further applied in the mass-conservative nutrient-phytoplankton-zooplankton-detritus（NPZD） model in this paper. Results showed that the nonsingular equilibrium point of NPZD model was analytically stable in use of the dimension reduction theorem and the Hopf bifurcation might occur when model parameters changed along the threshold values. The analytical results of the NPZD model were further verified by numerical simulation in this study. It can be concluded that this approach based on the dimension reduction theorem is well applicable to the theoretical analysis of a kind of stability problems and Hopf bifurcation of massconservative systems.

关键词： marine ecosystem mass-conservative NPZD stability Hopf bifurcation

Yb^(3+)-doped large-mode-area photonic crystal fiber laser with 210 W continuous-wave output power

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Chinese Science Bulletin 2009年第20期54卷 3670-3673页

作者： LI JianFeng DUAN KaiLiang liu yongzhi DAI ZhiYong OU ZhongHua liu Yong School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi'an 710119 China

An Yb3+-doped double-clad large-mode-area photonic crystal fiber(LMA PCF) laser with up to 210 W of continuous-wave output power centered at 1.05 μm is demonstrated.The length of the fiber used is 2 m and the produced laser power per meter can attain 105 W.The PCF is pumped by two diode lasers with central wavelength of 976 nm.The slope efficiency is 76%,and the beam quality factor M2 at x and y axes are measured to be 1.06 and 1.08,respectively.No thermo-optical problems and other roll-over even are observed at the highest output power.

关键词：光子晶体光纤高输出功率光纤激光器连续波面积二极管泵浦激光器光束质量因子镱

CuS/GO复合材料的构筑及对罗丹明B的高光催化活性

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高师理科学刊 2024年第6期44卷 50-53,61页

作者：刘勇智齐齐哈尔大学教学实验设备管理中心(工程训练中心) 黑龙江齐齐哈尔161006

光催化降解是一种有效降解罗丹明B的方法,为环境保护和人类健康做出了巨大的贡献,因此其具有广泛的应用前景.采用改良的Hummers法制备氧化石墨烯(GO),在此基础上,采用水热合成法制得硫化铜/氧化石墨烯(CuS/GO)纳米复合材料.通过傅里叶红... 详细信息

光催化降解是一种有效降解罗丹明B的方法,为环境保护和人类健康做出了巨大的贡献,因此其具有广泛的应用前景.采用改良的Hummers法制备氧化石墨烯(GO),在此基础上,采用水热合成法制得硫化铜/氧化石墨烯(CuS/GO)纳米复合材料.通过傅里叶红外(FITR)、X-射线衍射仪(XRD)、透射电子显微镜(TEM)、X-射线光电子能谱仪(XPS)等对复合材料进行表征.结果表明,随着醋酸铜含量的增加,负载在GO的CuS纳米粒子的量也随之增加,同时粒子尺寸也发生了变化.当醋酸铜含量占35.9%时,复合材料中CuS纳米粒子为3 nm,其形貌良好,负载均匀,且CuS的尺寸较小.CuS/GO复合材料对罗丹明B表现出了良好的光催化活性.

关键词： CuS/GO复合材料罗丹明B 光催化

保理合同中将有应收账款的转让标准--基于232份生效判决书的实证分析

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镇江高专学报 2024年第2期37卷 52-57页

作者：刘永智陈慎谦江苏财会职业学院财税学院江苏连云港222061 淮安市中级人民法院民三庭江苏淮安223001

在司法实践中,将有应收账款的转让标准存在争论,判决结果不一。通过实证分析发现,法院判断将有应收账款是否符合对外转让条件存在主体、客体与形式3类标准。结合将有应收账款的特征,明确将有应收账款主体标准为任一民事主体,统一客体标... 详细信息

在司法实践中,将有应收账款的转让标准存在争论,判决结果不一。通过实证分析发现,法院判断将有应收账款是否符合对外转让条件存在主体、客体与形式3类标准。结合将有应收账款的特征,明确将有应收账款主体标准为任一民事主体,统一客体标准为合理期待性,完善形式标准即建立预先通知与转让登记制度。

关键词：应收账款财产价值预先通知转让登记

基于最大均值差异的卷积神经网络故障诊断模型

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机电工程 2024年第3期41卷 445-454页

作者：包从望车守全刘永志陈俊张彩红六盘水师范学院矿业与机械工程学院贵州六盘水553000

针对工程场景中轴承故障数据采集困难,小样本下轴承故障诊断准确率较低且稳定性不高的问题,提出了一种小样本下滚动轴承故障的诊断方法,即基于最大均值差异(MMD)的卷积神经网络(CNN)诊断模型(方法)。首先,根据轴承故障机理,获取了滚动... 详细信息

针对工程场景中轴承故障数据采集困难,小样本下轴承故障诊断准确率较低且稳定性不高的问题,提出了一种小样本下滚动轴承故障的诊断方法,即基于最大均值差异(MMD)的卷积神经网络(CNN)诊断模型(方法)。首先,根据轴承故障机理,获取了滚动轴承故障的仿真信号,基于生成式对抗网络构建了仿真信号与少量真实样本间的对抗训练模型,得到了伪域样本,并将其扩充为训练数据集;其次,以交叉熵损失和最大均值差异(MMD)为卷积神经网络(CNN)的优化准则,引入了缩放因子,对网络进行了动态优化,根据测试结果选取缩放因子为0.05作为最优网络结构参数,构建了故障诊断的训练模型;最后,将结构均为1024个数据点的伪域样本和真实样本共同构成模型的训练集,对其进行了归一化处理,然后将其输入到构建的网络模型中,并以MMD作为约束,进行了卷积、池化操作,以实现特征提取的目的,经反向传播对模型进行了优化,实现了诊断模型参数的迭代更新目标。研究结果表明:基于MMD的CNN诊断模型(方法)对小样本下轴承的故障诊断识别精度有明显的改善,当样本数仅为16时,识别率可达95%以上,证明该方法在小样本下的轴承故障诊断中依然能获得较高的故障识别率。

关键词：滚动轴承故障诊断小样本生成式对抗网络卷积神经网络最大均值差异交叉熵损失

从“骨肉不相亲”探讨牛膝活性成分β-蜕皮甾酮论治骨质疏松的研究进展

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中华中医药学刊 2024年第4期42卷 254-258页

作者：商岚清刘永智周广智邰东旭康斯文辽宁中医药大学辽宁沈阳110847 辽宁中医药大学附属医院辽宁沈阳110032

骨质疏松是骨稳态失衡的一种全身性骨代谢紊乱疾病。临床常用药物如双膦酸盐、地诺单抗及雷奈酸锶等具有胃肠道刺激、肾毒性等不良反应,亟待安全长期有效的新型药物弥补空白。中医学中骨质疏松症属于“骨痿”范畴,牛膝是中医药治疗“骨... 详细信息

骨质疏松是骨稳态失衡的一种全身性骨代谢紊乱疾病。临床常用药物如双膦酸盐、地诺单抗及雷奈酸锶等具有胃肠道刺激、肾毒性等不良反应,亟待安全长期有效的新型药物弥补空白。中医学中骨质疏松症属于“骨痿”范畴,牛膝是中医药治疗“骨痿”的常见药物,β-蜕皮甾酮为其主要活性成分。通过β-蜕皮甾酮对于骨质疏松的治疗机制进行系统性综述,并以其对骨骼与肌肉分子调控为切入,结合牛膝中医中药理论及结合现代分子医学及生物学研究,总结出增加成骨细胞活性、促进骨髓间充质干细胞成骨分化、提高肌肉质量以及类雌激素等作用。

关键词： β-蜕皮甾酮牛膝骨肉不相亲骨质疏松骨骼骨骼肌

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