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Synthesis and fluorescent properties in complexes of Eu( Ⅲ), Tb( Ⅲ), and Sm( Ⅲ) with β-diketone and 2,2′-bipyridine

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Rare Metals 2012年第5期31卷 -页

作者： LIU Xingwang JIANG Jiadong GUO Yuwei YONG shengli YANG Kun NIE Lu School of Chemistry Baotou Teachers' College Baotou 014030 China School of Chemical Engineering Inner Mongolia University of Technology Hohhot 010051 China

Three new rare earth ternary complexes, RE(PB)_3bpy (RE=Sm^(3+) , Eu^(3+) , and Tb^(3+) ), were synthesized by the reaction of 1-(p-phenylethynyl- phenyl)-1,3-butanedione (HPB) and 2,2′-bipyridine (bpy) with rare earth chloride RECl_3 , respectively, in alcohol solution. The compositions were characterized by means of infrared (IR) spectra, chemical analysis, elemental analysis, and thermodynamic analysis. Luminescent properties of the three complexes were studied. At room temperature, under UV light excitation, the Sm^(3+) , Eu^(3+) , and Tb^(3+) complexes exhibit characteristic emission of the central ions. The fluorescence spectra show that the fluorescence emission intensity of Eu^(3+) complex is the strongest. The narrow strongest emission band of Eu^(3+) complex is considered to be a valuable material with bright red fluorescence.

关键词： β-diketone 2,2′-bipyridine lanthanide complex luminescent property

A novel method of suppressing machining vibration in robotic milling using magneto-rheological foam damper

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Chinese Journal of Aeronautics 2024年第12期37卷 522-543页

作者： Bo LI Chenxin SU Wei ZHAO shengli SONG Wei TIAN Wenhe LIAO College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Intelligent Manufacturing System Technology Beijing 100854China

Owing to their remarkable flexibility and favorable cost-effectiveness,industrial robots have found extensive applications to cutting of materials across sophisticated manufacturing ***,the structurally low rigidity of these robots renders the tool tip prone to substantial oscillations during machining processes,significantly impacting product fabrication *** objective of this study is to present a novel methodology employing magnetorheological dampers for mitigating vibrations during robotic milling ***,a new type of ring nested Magneto-Rheological Foam Damper(MRFD)working in the squeeze mode is ***,the MRFD’s structure is designed considering the vibrational characteristics of robotic ***,a damping force model of the MRFD is *** feasibility of the MRFD’s structural design is validated by the finite element analyses,which is instrumental in comprehending the influence of structural parameters on the electromagnetic characteristics of the ***,a prototype of the MRFD is fabricated selecting appropriate ***,a series of excitation and milling experiments are conducted on a KUKA KR500 *** outcomes demonstrate a substantial reduction(37%-69%)in radial vibration amplitude at the tool tip during robotic milling,highlighting the effectiveness of the developed *** research endeavor has introduced a pioneering avenue and framework for vibration control in robotic milling,offering a novel paradigm for enhancing the precision of robotic machining.

关键词： Industrial robots Machining vibration Magneto-rheological dampers Robotic milling Vibration suppression

N-carbamylglutamate restores nitric oxide synthesis and attenuates high altitudeinduced pulmonary hypertension in Holstein heifers ascended to high altitude

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Journal of Animal Science and Biotechnology 2018年第4期9卷 1000-1007页

作者： Shuxiang Wang Arash Azarfar Yajing Wang Zhijun Cao shengli Li State Key Laboratory of Animal Nutrition Beijing Engineering Technology Research Center of Raw Milk Quality and Safety Control College of Animal Science and Technology China Agricultural University Faculty of Agriculture Department of Animal Science Lorestan University

Background: High-altitude pulmonary hypertension(HAPH) is a life-threating condition for animals in high altitude,and disturbance of endothelial nitric oxide(NO) synthesis contributes to its pathogenesis. N-carbamylglutamate(NCG), which enhances arginine synthesis, promotes endogenous synthesis of NO. In this study, we determined the effects of NCG on alleviating HAPH in Holstein heifers that ascended to Tibet(Lhasa, 3,658 m).Methods: Exp. 1, 2,000 Holstein heifers were transported from low elevation(1,027 m) to Lhasa. After being exposed to hypoxia for 1 yr, Holstein heifers were assigned to a healthy group(Control, n = 6) with mean pulmonary hypertension(mPAP) 49 *** tissues were collected to evaluate histopathological changes and the expression of endothelial nitric oxide synthase(eNOS). Exp. 2, ten healthy heifers and 10 HAPH affected heifers were supplemented with NCG(20 g/d per heifer) for 4 wk. Physiological parameters were determined and blood samples were collected on d-1 and d 28 of the feeding ***: Expression of e NOS in small pulmonary arteriole intima was higher in the healthy than HAPH group(P = 0.006), whereas HAPH group had significantly thicker media and adventitia than healthy group(all P < 0.05). The mRNA of eNOS and protein level of eNOS were higher in the lungs of heifers in the healthy group than in the HAPH group(both P < 0.001), whereas endothelin-1 protein levels were higher in HAPH group than in the healthy group(P = 0.025). NCG supplementation decreased mPAP and ammonia(both P = 0.001), whereas it increased the expression of eNOS, arginine, and plasma NO(all P < 0.05).Conclusions: The expression of eNOS was decreased in Holstein heifers with HAPH. NCG supplementation decreased m PAP through the restoration of eNOS and endogenous NO synthesis.

关键词： High-altitude pulmonary hypertension Holstein heifers N-carbamylglutamate Tibet

Transplanted choroidal plexus epithelial cells can integrate with organotypic spinal cord slices into a new system

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BIOCELL 2022年第6期46卷 1537-1544页

作者： JINGJIE LIU XIAOYAN diNG LI XIANG shengli HUANG Department of Neurology The Second Affiliated HospitalCollege of MedicineXi’an Jiaotong UniversityXi’an710004China Department of Ophthalmology Xi’an No.3 HospitalXi’an710018China Department of Orthopedics The Second Affiliated HospitalCollege of MedicineXi’an Jiaotong UniversityXi’an710004China

This study aimed to evaluate the integration of transplanted choroidal plexus epithelial cells with organotypic spinal cord *** spinal cord slices,normally cultured for 6 days,were divided into control group(Ctrl)and transplanted group(T).The choroidal plexus epithelial cells were dissociated and primary cultured(C group).The choroidal plexus epithelial cells cultured for 6–7 days were labeled by 1,1’-dioctadecyl-3,3,3’,3’-tetramethylindocarbocyanineperchlorate(CM-dil),and were identified by transthyretin(TTR)in *** were adjusted to the density of 0.5–1×107/ml,then 2μl cells suspension were transplanted to the spinal cord slices in the T *** same amount of basal medium was dripped on the spinal cord slices in the Ctrl *** 14 days of transplantation,the differentiations into neurons and astrocytes,and the synapses were identified by immunofluorescence *** the same time,the ratios of cell differentiations and synapses in new system,and the changes of MAPK signaling pathway were tested by western *** choroid plexus epithelial cells were well labeled by CM-dil and were immune-stained by TTR in *** choroid plexus epithelial cells bodies were small when transplanted on the spinal cord slices,but big when transplanted on the polyester membrane *** transplanted cells could differentiate into astrocytes,and possibly differentiate into neurons,and there were a large number of synaptophysin positive vesicles between transplanted cells and organotypic spinal cord slices in immunofluorescence *** levels of GFAP,TUB-III and synaptophysin in the T group were higher than which in the Ctrl and C groups in western blotting(P<0.05).And the ratios of p-JNK/JNK and p-P38/P38 in the T group were significantly lower than which in the Ctrl and C groups(P<0.05).But the ratio of p-ERK/ERK in the three groups was of no significant *** transplanted choroidal plexus epi

关键词： Cell transplantation Choroidal plexus epithelial cells Integration Organotypic spinal cord slices

Ion-vacancy coupled charge transfer model for ion transport in concentrated solutions

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Science China Chemistry 2019年第4期62卷 515-520页

作者： Yu Gao Jun Huang Yuwen Liu Jawei Yan Bingwei Mao shengli Chen Hubei Key Laboratory of Electrochemical Power Sources Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) Department of Chemistry Wuhan University Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical Engineering Central South University State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry Xiamen University

We present a conceptual framework for understanding and formulating ion transport in concentrated solutions, which pictures the ion transport as an ion-vacancy coupled charge transfer reaction. A key element in this picture is that the transport of an ion from an occupied to unoccupied site involves a transition state which exerts double volume exclusion. An ab initio random walk model is proposed to describe this process. Subsequent coarse-graining results in a continuum formula as a function of chemical potentials of the constituents, which are further derived from a lattice-gas model. The subtlety here is that what has been taken to be the chemical potential of the ion in the past is actually that of the ion-vacancy couple. By aid of this new concept, the driving force of ion transport is essentially the chemical affinity of the ion-vacancy coupled charge transfer reaction, which is a useful concept to unify transport and reaction, two fundamental processes in electrochemistry. This phenomenological model is parameterized for a specific material by the aid of first-principles calculations. Moreover, its extension to multiple-component systems is discussed.

关键词： concentrated solutions ion dynamics ion volume effect chemical affinity ion-vacancy couple

Density functional theory (DFT)-based modified embedded atom method potentials: Bridging the gap between nanoscale theoretical simulations and DFT calculations

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Science China Chemistry 2010年第2期53卷 411-418,454-455页

作者： YANG Fan LIU YuWen OU LiHui WANG Xin CHEN shengli Hubei Electrochemical Power Sources Key Laboratory Department of ChemistryWuhan UniversityWuhan 430072China School of Chemical and Biomedical Engineering Nanyang Technological UniversitySingapore

A density functional theory (DFT)-calculation scheme for constructing the modified embedded atom method (MEAM) potentials for face-centered cubic (fcc) metals is presented. The input quantities are carefully selected and a more reliable DFT approach for surface energy determination is introduced in the parameterization scheme, enabling MEAM to precisely predict the surface and nanoscale properties of metallic materials. Molecular dynamics simulations on Pt and Au crystals show that the parameterization employed leads to significantly improved accuracy of MEAM in calculating the surface and nanoscale properties, with the results agreeing well with both DFT calculations and experimental observations. The present study implies that rational DFT parameterization of MEAM may lead to a theoretical tool to bridge the gap between nanoscale theoretical simulations and DFT calculations.

关键词： theoretical simulations MEAM DFT parameterization nanoparticles

HASN:A Hierarchical Attack Surface Network for System Security Analysis

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China Communications 2019年第5期16卷 137-157页

作者： Kangyu Huang Lin Yang Renfang Fu shengli Zhou Zheng Hong College of Command and Control Engineering Army Engineering UniversityNanjing 210007China China Electronic Equipment & System Engineering Corporation Beijing 100141China State Grid Jiangsu Electric Power Company Research Institute Nanjing 210019China Information Department of Zhejiang Police College Hangzhou 310053China

Attack surfaces, as one of the security models, can help people to analyse the security of systems in cyberspace, such as risk assessment by utilizing various security metrics or providing a cost-effective network hardening solution. Numerous attack surface models have been proposed in the past decade,but they are not appropriate for describing complex systems with heterogeneous components. To address this limitation, we propose to use a two-layer Hierarchical Attack Surface Network(HASN) that models the data interactions and resource distribution of the system in a component-oriented view. First, we formally define the HASN by extending the entry point and exit point framework. Second, in order to assess data input risk and output risk on the HASN, we propose two behaviour models and two simulation-based risk metrics. Last, we conduct experiments for three network systems. Our experimental results show that the proposed approach is applicable and effective.

关键词： attack surface security analysis security model risk assessment

Shock tube study on auto-ignition characteristics of kerosene/air mixtures

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Chinese Science Bulletin 2011年第13期56卷 1399-1406页

作者： ZHANG YingJia HUANG ZuoHua WANG JinHua XU shengli State Key Laboratory of Multiphase Flow in Power Engineering Xi' an Jiaotong University Xi' an 710049 China Department of Modern Mechanics University of Science and Technology of China Hefei 230026 China

Ignition delay times are obtained for kerosene/air mixtures behind the reflected shock waves at temperatures between 1445 and 1650 K,at a pressure of 0.11 MPa and an equivalence ratio of 1.0.A nebulization device with Laval nozzle is used to nebulize kerosene and form an aerosol phase,which evaporates and diffuses rapidly behind the incident shock *** auto-ignite behind the reflected shock *** ICCD is used to visualize the kerosene/air mixture's ignition *** mixture's ignition intensity increases with increase in initial *** and irregular flames exist below 1515 K while plane and discontinuous flames exist over 1560 *** delay times decrease with increase in initial *** data shows good agreement with results reported previously in the literature.A new surrogate (consisting of 10% toluene,10% ethylbenzene and 80% n-decane) is proposed for *** et al.'s mechanism is used to simulate the ignition of kerosene with calculations agreeing well with the experimental *** sensitivity of reaction H+O2 OH+O,which shows the highest sensitivity to the ignition delay time,increases with an increase in *** chain breaching reaction of CH3 with O2 accelerates the total reaction rate and the H-atom abstraction of n-decane controls the total reaction *** rate of production and instantaneous heat production indicate that two reactions,H+O2 OH+O and O+H2 OH+H,are the key reactions to the formation of OH radicals,as well as the main endothermic ***,the reaction of R3 is the main heat release reaction during *** structure analysis shows that initial pressure is increased slightly as CO and H2O will appear before main ignition.

关键词：空气混合物煤油自燃特性点火延迟时间冲击管反应速率初始温度数据显示

Training Generative Adversarial Networks with Adaptive Composite Gradient

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Data Intelligence 2024年第1期6卷 120-157页

作者： Huiqing Qi Fang Li shengli Tan Xiangyun Zhang School of Mathematical Sciences East China Normal UniversityShanghai 200241China

The wide applications of Generative adversarial networks benefit from the successful training methods,guaranteeing that an object function converges to the local ***,designing an efficient and competitive training method is still a challenging task due to the cyclic behaviors of some gradient-based ways and the expensive computational cost of acquiring the Hessian *** address this problem,we proposed the Adaptive Composite Gradients(ACG)method,linearly convergent in bilinear games under suitable *** analysis and toy-function experiments both suggest that our approach alleviates the cyclic behaviors and converges faster than recently proposed SOTA *** convergence speed of the ACG is improved by 33%than other *** ACG method is a novel Semi-Gradient-Free algorithm that can reduce the computational cost of gradient and Hessian by utilizing the predictive information in future *** mixture of Gaussians experiments and real-world digital image generative experiments show that our ACG method outperforms several existing technologies,illustrating the superiority and efficacy of our method.

关键词： Generative adversarial networks adaptive composite gradient semi-gradient free game theory bilinear game