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基于EEMD-Hilbert包络谱和DBN的变负载下滚动轴承状态识别方法

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中国电机工程学报 2017年第23期37卷 6943-6950页

作者：王玉静那晓栋康守强谢金宝 V i MiKULOViCH 哈尔滨理工大学电气与电子工程学院黑龙江省哈尔滨市150080 白俄罗斯国立大学白俄罗斯明斯克220030

负载在滚动轴承的运行过程中通常是变化的,针对变负载下滚动轴承不同故障位置及不同性能退化程度多状态识别困难的问题,提出一种基于集合经验模态分解–希尔伯特(ensemble empirical mode decomposition-Hilbert,EEMD-Hilbert)包络谱和... 详细信息

负载在滚动轴承的运行过程中通常是变化的,针对变负载下滚动轴承不同故障位置及不同性能退化程度多状态识别困难的问题,提出一种基于集合经验模态分解–希尔伯特(ensemble empirical mode decomposition-Hilbert,EEMD-Hilbert)包络谱和深度信念网络(deep belief network,DBN)的滚动轴承状态识别方法。该方法首先对滚动轴承各状态振动信号进行EEMD,然后选取敏感本征模态函数(intrinsic mode function,iMF),并对其进行Hilbert变换求取包络谱。最后将各状态振动信号的iMF包络谱按顺序构建新的高维数据,输入到经遗传算法优化各隐藏层节点结构的DBN中,实现变负载下滚动轴承的多状态识别。实验结果表明:在运用DBN进行滚动轴承10种状态识别过程中,训练数据采用某种负载,测试数据选用其他负载的情况下,EEMD-Hilbert包络谱比时域或频域幅值谱能更好地体现出滚动轴承不同负载下的多状态特征;且DBN相对浅层学习的支持向量机和BP神经网络算法,具有更高的识别率,各数据集识别率均达到92.5%以上。

关键词：变负载滚动轴承集合经验模态分解深度信念网络状态识别

Superior biocompatibility and comparable osteoinductive properties: Sodium-reduced fluoride-containing bioactive glass belonging to the CaO–MgO–SiO2 system as a promising alterna.i.e to 45S5 bioactive glass

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Bioactive Materials 2020年第1期5卷 55-65页

作者： S.i.Schmitz B.Widholz C.Essers M.Becker D.U.Tulyaganov A.Moghaddam i.Gonzalo de Juan F.Westhauser Center of Orthopedics Traumatology and Spinal Cord InjuryHeidelberg University HospitalSchlierbacher Landstraße 200a69118HeidelbergGermany Disperse Solid Materials Technical University DarmstadtOtto-Berndt-Straße 364287DarmstadtGermany Department of natural-Mathematical Sciences Turin Polytechnic University in Tashkent17 Small Ring Street100095TashkentUzbekistan ATORG-Aschaffenburg Trauma and Orthopedic Research Group Center for Trauma SurgeryOrthopedicsand Sports MedicineKlinikum Aschaffenburg-AlzenauAm Hasenkopf 163739AschaffenburgGermany

Bioactive glasses(BGs)are promising bone substitute ***,under certain circumstances BGs such as the well-known 45S5 Bioglass®(composition in wt%:45.0 SiO2,24.5 na2O,24.5 CaO,6.0 P2O5)act cytotoxic due to a strong increase in pH caused by a burst release of sodium ions.A potential alterna.i.e is a sodiumreduced fluoride-containing BG belonging to the CaO–MgO–SiO2 system,namely BG1d-BG(composition in wt%:46.1 SiO2,28.7 CaO,8.8 MgO,6.2 P2O5,5.7 CaF2,4.5 na2O),that has already been evaluated in-vitro,in-vivo and in preliminary clinical *** further application,however,BG1d-BG should be compared to the benchmark amongst BGs,the 45S5 Bioglass®composition,to classify its effect on cell viability,proliferation and osteogenic differentiation of human mesenchymal stem cells(MSCs).Therefore,in this study,the biocompatibility and osteogenic potential of both BGs were investigated in an indirect and direct culture setting to assess the effect of the ionic dissolution products and the BGs’physical presence on the *** results indicated an advantage of BG1d-BG over 45S5 Bioglass®regarding cell viability and *** BGs induced an earlier onset of osteogenic differentiation and accelerated the expression of late osteoblast marker genes compared to the control *** conclusion,BG1d-BG is an attractive candidate for further experimental *** basic mechanisms behind the different impact on cell behavior should be assessed in further detail,*** further alteration of the BG compositions.

关键词： 45S5 Bioglass® Sodium-reduced bioactive glass Fluoride-containing bioactive glass Bone tissue engineering Human mesenchymal stromal cells

Metal-organic framework-derived porous shuttle-like vana.i.m oxides for sodium-ion battery application

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nano Research 2018年第1期11卷 449-463页

作者： Yangsheng Cai Guozhao Fang Jiang Zhou Sainan Liu Zhigao Luo Anqiang Pan Guozhong Cao i Shuquan Liang School of Materials Science and Engineering Central South University Changsha 410083 China Key Laboratory of Nonferrous Metal Materials Science and Engineering Ministry of Education Central South University Changsha 410083 China Department of Materials and Engineering University of Washington Seattle WA 98195-2120 USA

Vana.i.m oxides with a layered structure are promising candidates for both lithium-ion batteries and sodium-ion batteries （SiBs）. The self-template approach, which involves a transformation from metal-organic frameworks （MOFs） into porous metal oxides, is a novel and effective way to achieve desirable electrochemical performance. in this stud~ porous shuttle-like vana.i.m oxides （i.e., V205, V203/C） were successfully prepared by using MiL-88B （V） as precursors with a specific calcina.i.n process. As a proof-of-concept application, the as- prepared porous shuttle-like VaOdC was used as an anode material for SiBs. The porous shuttle-like V203/C, which had an inherent layered structure with metallic behavior, exhibited excellent electrochemical properties. Remarkable rate capacities of 417, 247, 202, 176, 164, and 149 mAh.g-1 were achieved at current densities of 50, 100, 200, 500, 1,000, and 2,000 mA.g-1, respectively. Under cycling at 2 A.g-1, the specific discharge capacity reached 181 mAh.g-1, with a low capacity fading rate of 0.032% per cycle after 1,000 cycles. Density functional theory calculation results indicated that na.i.ns preferred to occupy the interlamina.i.n rather than the inside of each layer in the V203. interestingly, the special layered structure with a skeleton of dumbbell-like V-V bonds and metallic behavior was maintained after the insertion of na.i.ns, which was beneficial for the cycle performance. We consider that the MOF precursor of MiL-88B （V） can be used to synthesize other porous V-based materials for various applications.

关键词： vana.i.m oxides metal-organic frameworks porous structure density functional theory(DFT) calculation sodium-ion batteries

东昆仑南带中元古代晚期—新元古代早期叠层石组合的发现

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地质科学 2006年第3期41卷 500-510,i0003-i0005页

作者：边千韬朱士兴 i.i.Pospelov M.A.Semikhatov 孙淑芬陈代钊那春光中国科学院地质与地球物理研究所中国地质调查局天津地质矿产研究所 Geological institute Russian Academy of Sciences Moscow 109017 Russia

东昆仑南带加嗡门地区碳酸盐岩地层中发现的中元古代晚期-新元古代早期叠层石组合以大型锥叠层石及其相关的分子Conophyton garganicus ***，*** Menchikov，Jacutophyton f．和Conicodomenia f．等最丰富，并与Baicalia共生，故可视之... 详细信息

东昆仑南带加嗡门地区碳酸盐岩地层中发现的中元古代晚期-新元古代早期叠层石组合以大型锥叠层石及其相关的分子Conophyton garganicus ***，*** Menchikov，Jacutophyton f．和Conicodomenia f．等最丰富，并与Baicalia共生，故可视之为Conophyton--Baicalia组合。该叠层石组合可以与天山和华北等地蓟县系中部-青白口系中部叠层石组合对比，尤其酷似于天山地区蓟县系的爱尔基干组合和华北蓟县系的闪坡岭叠层石组合，而显著有别于华南地块。它还可以与南乌拉尔、西伯利亚、北美、北非和阿拉斯加半岛等地区的中里菲界上部-上里菲界下部层位中的叠层石组合对比。加嗡门叠层石组合的时限为距今1 300～850Ma，大致为蓟县纪中期一青白口纪中期或中里菲晚期一晚里菲早期。东昆仑南带存在前寒武纪微地块，当时此微地块的古地理和古环境与天山、华北、西伯利亚和阿拉斯加半岛等地区的前寒武纪地块相似，均位于低纬度区，其上均广泛发育适宜叠层石繁育的温暖陆表海，它们可能共同处于罗迪尼亚超大陆的低纬度大陆边缘部位，与华南地块的不同。这对本区和东昆仑地层和大地构造研究，以及对罗迪尼亚超大陆重建提供了新的古生物约束。

关键词：叠层石中元古代晚期-新元古代早期罗迪尼亚超大陆东昆仑

Targeting cAMP in D1-MSNs in the nucleus accumbens, a new rapid antidepressant strategy

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Acta Pharmaceutica Sinica B 2024年第2期14卷 667-681页

作者： Yue Zhang Jingwen Gao na Li Peng Xu Shimeng Qu Jinqian Cheng Mingrui Wang Xueru Li Yaheng Song Fan Xiao Xinyu Yang Jihong Liu Hao Hong Ronghao Mu Xiaotian Li Youmei Wang Hui Xu Yuan Xie Tianming Gao Guangji Wang Jiye Aa Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics State Key Laboratory of Natural MedicinesResearch Unit of PK-PD Based Bioactive Components and Pharmacodynamic Target Discovery of Natural Medicine of Chinese Academy of Medical SciencesChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Drug Monitoring and Control Drug Intelligence and Forensic CenterMinistry of Public SecurityBeijing 100193China School of Pharmacy China Pharmaceutical UniversityNanjing 211198China School of Foreign Languages China Pharmaceutical UniversityNanjing 211198China Department of Neurobiology School of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515China Department of Pharmacology China Pharmaceutical UniversityNanjing 211198China School of Pharmaceutical Sciences Zhengzhou UniversityZhengzhou 450001China

Studies have suggested that the nucleus accumbens(nac)is implicated in the pathophysiology of major depression;however,the regulatory strategy that targets the nac to achieve an exclusive and outstanding anti-depression benefit has not been ***,we identified a specific reduction of cyclic adenosine monophosphate(cAMP)in the subset of dopamine D1 receptor medium spiny neurons(D1-MSNs)in the nac that promoted stress susceptibility,while the stimulation of cAMP production in nac D1-MSNs efficiently rescued depression-like *** treatment enhanced cAMP both in D1-MSNs and dopamine D2 receptor medium spiny neurons(D2-MSNs)of depressed mice,however,the rapid antidepressant effect of ketamine solely depended on elevating cAMP in nac *** discovered that a higher dose of crocin markedly increased cAMP in the nac and consistently relieved depression 24 h after oral administration,but not a lower *** fast onset property of crocin was verified through multicenter ***,crocin specifically targeted at D1-MSN cAMP signa.i.g in the nac to relieve depression and had no effect on *** findings characterize a new strategy to achieve an exclusive and outstanding anti-depression benefit by elevating cAMP in D1-MSNs in the nac,and provide a potential rapid antidepressant drug candidate,crocin.

关键词： CAMP Nucleus accumbens Depression D1-MSN D2-MSN

Semi-oxalate synthesis of (1-x)BaTiO3-xM0.5Bi0.5TiO3 (M =Li, na, K)PTCR materials

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Journal of Advanced Ceramics 2016年第2期5卷 117-125页

作者： T.A.PLUTENKO O.i.V'YUNOV A.G.BELOUS O.Z.YANCHEVSKii Vernadskii institute of General and inorganic Chemistry of the Ukrainian naS Prospect Palladina 32/34 Kyiv 142 03680 Ukraine

(1−x)BaTiO3–xM0.5Bi0.5TiO3 (M = Li, na, K) solid solutions were prepared using BaTiO3 pre-synthesized by oxalate method. The stability limits of (1−x)BaTiO3–xLi0.5Bi0.5TiO3 solid solutions have been established. it was shown that increase in M0.5Bi0.5TiO3 concentration results in reduction of ceramic grain size in the (1−x)BaTiO3−xM0.5Bi0.5TiO3 (M = Li, na, K) system. it was found that the positive temperature coefficient of resistance (PTCR) effect in lead-free materials is due to the presence of a semiconductor core, which is formed by sintering under reducing atmosphere, and dielectric grain boundaries, formed on additional oxidation in air. The use of barium titanate, pre-synthesized by oxalate method, in the synthesis of solid solutions reduced the sintering temperature of ceramics compared with solid state reaction technique. By comparing the electrical properties of the synthesized lead-containing and lead-free materials, it has been shown that lead-free materials exhibit better electrical properties for practical use compared with lead-containing materials.

关键词： lead-free ceramic BaTiO3 semi-oxalate method positive temperature coefficient of resistance (PTCR) effect

青海省布青山早古生代末期埃达克岩的发现及其构造意义

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岩石学报 2007年第5期23卷 925-934页

作者：边千韬 Pospelov i.i. 李惠民常承法李继亮中国科学院地质与地球物理研究所 Geological institute Russian Academy of SciencesMoscow 109017Russia 中国地质调查局天津地质矿产研究所

在青藏高原北部阿尼玛卿蛇绿岩带布青山段首次发现了埃达克岩,它们多呈不规则岩脉状侵入于布青山地区北部早古生代蛇绿混杂岩中。其岩性为花岗-英云闪长岩,主矿物有斜长石、石英、黑云母、角闪石、少量钾长石和辉石;副矿物有榍石、磷灰... 详细信息

在青藏高原北部阿尼玛卿蛇绿岩带布青山段首次发现了埃达克岩,它们多呈不规则岩脉状侵入于布青山地区北部早古生代蛇绿混杂岩中。其岩性为花岗-英云闪长岩,主矿物有斜长石、石英、黑云母、角闪石、少量钾长石和辉石;副矿物有榍石、磷灰石、锆石和磁铁矿等。属钙碱系列,具典型(Ⅰ类、O型、HSA)埃达克岩的地球化学特征,表现为:高SiO_2(63. 65%～71.59%),高Al_2O_3(14.81%～16.11%),高na_2O(4.68%～5.33%)和na_2O/K_2O(1.48～3.08,平均2.39),高Sr (444.08×10^(-6)～560.41×10^(-6))和Sr/Y(50.8～105.3),HREE强烈亏损,低Yb(0.38×10^(-6)～0.74×10^(-6)),高La/Yb(44.93～90.97),弱负Eu异常(δEu=0.74～0.90),富集大离子亲石元素(LiLE),亏损高场强元素(HFSE),Ba、Pb正异常而Nb、P负异常。获得布青山埃达克岩的锆石TiMS U-Pb年龄为402±24Ma。布青山埃达克岩熔体来自俯冲的昆祁秦洋壳(含海洋沉积物)在石榴石角闪岩相条件下部分熔融,主要残留相为石榴石(±角闪石)。布青山埃达克岩的发现指示早古生代末期洋壳(昆祁秦多岛洋的一部分)俯冲作用的存在,俯冲方向朝北(现在方位),此前,俯冲带发生长时间的向洋迁移,早古生代末期俯冲带已后退到阿尼玛卿蛇绿混杂岩带以南;暗示典型埃达克岩也可以形成于洋壳俯冲晚期;提示阿尼玛卿蛇绿岩带可能有与典型埃达克岩有关的Au、Ag、Cu、Mo等热液和斑岩矿床。

关键词：埃达克岩地球化学早古生代末期青藏高原阿尼玛卿蛇绿岩带

miR-206对腰椎间盘突出症大鼠髓核炎症、镇痛及自噬相关蛋白的作用机制

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中国组织工程研究 2024年第11期28卷 1712-1718页

作者：王美索娜于欢杨建博哈励逊国际和平医院河北省衡水市053000

背景:研究发现,腰椎间盘突出症患者的疼痛机制与炎症相关,自噬与椎间盘疾病及炎症反应密切相关,miR-206表达异常可促进骨骼疾病的发生。目的:探讨miR-206对腰椎间盘突出大鼠髓核炎症、镇痛及自噬相关蛋白的作用机制。方法:SPF级雄性SD大... 详细信息

背景:研究发现,腰椎间盘突出症患者的疼痛机制与炎症相关,自噬与椎间盘疾病及炎症反应密切相关,miR-206表达异常可促进骨骼疾病的发生。目的:探讨miR-206对腰椎间盘突出大鼠髓核炎症、镇痛及自噬相关蛋白的作用机制。方法:SPF级雄性SD大鼠60只按照随机数字方法分为对照组、模型组、miR-206 mimics-NC组、miR-206 mimics组、miR-206 inhibitor-NC组及miR-206 inhibitor组。除对照组外均建立腰椎间盘突出症大鼠模型,建模后第10天miR-206 mimics-NC组、miR-206 mimics组、miR-206 inhibitor-NC组及miR-206 inhibitor组分别在损伤处注射miR-206 mimics-NC、miR-206 mimics(miR-206模拟物)、miR-206 inhibitor-NC及miR-206 inhibitor(miR-206抑制物),均20μmol/L,10μL,1次/d,连续注射4 d;对照组及模型组均注射等剂量生理盐水。Von Frey纤维丝测定大鼠双侧后足机械性缩足反射阈值,热痛测试仪检测大鼠双侧后足热刺激缩足反射潜伏期;苏木精-伊红染色观察背根神经节组织形态;qPCR检测各组大鼠髓核组织炎症因子磷脂酶A2、环氧化酶2、前列腺素E2、肿瘤坏死因子α、白细胞介素1β表达;免疫印迹检测自噬相关蛋白LC3Ⅰ、Beclin-1表达。结果与结论:①造模后3,7及14 d时,与对照组相比,模型组大鼠机械性缩足反射阈值、热刺激缩足反射潜伏期降低,磷脂酶A2、环氧化酶2、前列腺素E2、肿瘤坏死因子α、白细胞介素1β、LC3Ⅰ、Beclin-1表达升高(PiR-206 inhibitor-NC组、miR-206 mimics-NC组上述指标与模型组相比差异无显著性意义(P>0.05);②与miR-206 mimics-NC组相比,miR-206 mimics组大鼠机械性缩足反射阈值、热刺激缩足反射潜伏期降低,磷脂酶A2、环氧化酶2、前列腺素E2、肿瘤坏死因子α、白细胞介素1β、LC3Ⅰ、Beclin-1水平升高(PiR-206 inhibitor-NC组相比,miR-206 inhibitor组大鼠上述指标呈相反变化,差异均有显著性意义(PiR-206可以显著改善腰椎间盘突出症大鼠髓核炎症因子水平,提高疼痛阈值,降低细胞自噬,其作用机制与抑制LC3Ⅰ、Beclin-1表达相关。

关键词：腰椎间盘突出症 miR-206 炎症镇痛自噬

Evaluation of the Cr(Vi) and other toxic element contamina.i.n and their potential sources:The case of the Thiva basin(Greece)

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Geoscience Frontiers 2012年第4期3卷 523-539页

作者： M.Economou-Eliopoulos D.Antivachi Ch.Vasilatos i.Megremi Department of Geology & Geoenvironment Section of Economic Geology & Geochemistry.University of AthensPanepistimiopolisAthens 15784Greece

An integrated approach was performed on the soil, plant-crops and groundwater system at the Thiva basin, to evaluate the extent and intensity of the heavy metal contamina.i.n, the percentage of metals transferred into plants/crops （bio-accumulation） and the potential sources of contamina.i.n. Heavy metal contents （230--310 Cr, 1200--2200 Ni, 50--80 Co, 880--1150 Mn and 44,500--66,200 Fe all in ppm ） in the Thiva soils are higher than those in the Assopos basin. An increasing trend in the heavy metal contents, from the Assopos to the Thiva basin （Mouriki）, indicates that the metal source is probably the Ni-laterites and ophiolites, located towards north. On the other hand, groundwater samples from domestic and irrigation wells throughout the Thiva basin exhibit relatively low （8--37 ppb） concentrations in Cr compared to the Assopos （up to 150 ppb）. The plots of Cr versus Mg/Ca, Mg/na versus Ca/na, B versus Si/（Si ＋ na） and Mg/Si versus Ca/Si ratios revealed a low degree of salinization in the Thiva compared to that in the Assopos （Avlida） basin. The low Cr concentration （average 23 ppb, during dry period） in the Thiva wells may be related with their depth （〉120 m）, in contrast to shallow wells in the central Euboea （hundreds ppb Cr） and points to a solution of a crucial environmental problem in Euboea and Assopos basin by using the deep karst-type aquifer instead the shallow-Neogene one. The average Cr contents （dry weight） ranges from 1.7 to 4.6 ppm （average 2.2） in carrots, potatoes and onions. The percentage of soil metals Crto^i, Cr（Vl）, Ni, Mn and Fe ranges between 0.06 and 3.2 （average （/.53 ~ 0.4）, whilst that for Cu and Zn ranges from 16 to 81 （average 36 ~ 24）. The Cr transfer to plants is low, due to the high resistance of chromite （main host of Cr）, but the determined Cr contents in plant- crops in the Thiva basin are higher than normal or sufficient vahles. Although mininml uptake for growth and production for Cr, Ni, Zn and Cn is still lacking, fnrtherm

关键词： Cr(Vi) Contamina.i.n Plants Groundwater Bio-accumulation Thiva