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Chinese Science Bulletin 2014年第27期59卷 3398-3405页

作者： ying-ying Zhang shu-Xia Ren Jian-Jun Zhang Ning Ren shu-Ping Wang Testing and Analysis Center Hebei Normal University Material Science and Engineering School Shijiazhuang Tiedao University College of Chemistry and Material Science Hebei Normal University Department of Chemistry Handan College

A series of lanthanide complexes [Ln(4-Cl-2-MOBA)3phen]2(Ln=Sm(1), Nd(2), Ho(3), Eu(4), Dy(5), and Tb(6); 4-Cl-2-MOBA=4-chloro-2-methoxybenzoate, phen=1,10-phenanthroline) were synthesized and characterized. The single-crystal X-ray diffraction demonstrates that 1–3 are isomorphous, which present dimeric structures with four 4-Cl-2-MOBA anions function as bridging ligands. Complexes 1 and 4–6 display their characteristic luminescence emission bands of central Ln3?ions. The heat capacities, the thermodynamic functions and the thermogravimetry–Fourier transform infrared spectra of gaseous products of complexes 1–6 were *** non-isothermal kinetics of the second decomposition stage was studied by the integral isoconversional non-linear method and Stark method. Furthermore, 1–6 exhibited excellent antibacterial activity against Candida albicans,Escherichia coli and Staphylococcus aureu.

关键词：热分解动力学甲氧基苯甲酸稀土配合物晶体结构抗菌活性邻菲咯啉镧系元素金黄色葡萄球菌

Modeling the Earth's magnetosphere under the influence of solar wind with due northward IMF by the AMR-CESE-MHD model

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Science China Earth Sciences 2015年第7期58卷 1235-1242页

作者： WANG Juan DU AiMin ZHANG ying ZHANG TieLong ge YaSong State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Space Research Institute Austrian Academy of Sciences

We present a newly developed global magnetohydrodynamic(MHD) model to study the responses of the Earth's magnetosphere to the solar wind. The model is established by using the space-time conservation element and solution element(CESE) method in general curvilinear coordinates on a six-component grid system. As a preliminary study, this paper is to present the model's numerical results of the quasi-steady state and the dynamics of the Earth's magnetosphere under steady solar wind flow with due northward interplanetary magnetic field(IMF). The model results are found to be in good agreement with those published by other numerical magnetospheric models.

关键词： numerical simulation magnetosphere magnetohydrodynamic model adaptive mesh refinement technique the space-time conservation element and solution element method

Evolution, resilience and causes of global petroleum gas trade networks: 1995-2020

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Petroleum Science 2024年第5期21卷 3656-3674页

作者： Na Li Yi-Ran Song ying Wang Chun-Bao ge School of Economics and Management Xinjiang UniversityUrumqi830046XinjiangChina School of Business Nanjing UniversityNanjing210093JiangsuChina Hefei Advanced Research Institute Anhui University of Finance&EconomicsHefei230071AnhuiChina

Based on the HS 4-digit code trade data in UNCOMTRADE from 1995 to 2020, this paper analyzes the characteristics of the evolution of the global PG trade network using the complex network approach and analyzes the changes in its resilience at the overall and country levels, respectively. The results illustrated that:(1) The scale of the global PG trade network tends to expand, and the connection is gradually tightened, experiencing a change from a “supply-oriented” to a “supply-and-demand” pattern, in which the U.S., Russia, Qatar, and Australia have gradually replaced Canada, Japan, and Russia to become the core trade status, while OPEC countries such as Qatar, Algeria, and Kuwait mainly rely on PG exports to occupy the core of the global supply, and the trade status of other countries has been dynamically alternating and evolving.(2) The resilience of the global PG trade network is lower than that of the random network and decreases non-linearly with more disrupted countries. Moreover, the impact of the U.S. is more significant than the rest of countries. Simulations using the exponential random graph model(ERGM) model revealed that national GDP, institutional quality, common border and RTA network are the determinants of PG trade network formation, and the positive impact of the four factors not only varies significantly across regions and stages, but also increases with national network status.

关键词： Petroleum gas Complex network approach Network resilience Exponential random graph model

Study on the morphological regulation mechanism of hollow silica microsphere prepared via emulsion droplet template

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Chinese Chemical Letters 2023年第4期34卷 575-579页

作者： Chu Zhao Zhiqing ge Zhuoni Jiang shuo Yan Jingjing shu Mozhen Wang Xuewu ge CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China

The morphology regulation of hollow silica microspheres is significant for their properties and applications. In this paper, hollow silica microspheres were formed through the hydrolysis and condensation reaction of tetraethyl orthosilicate(TEOS) at the interface of the emulsion droplet templates composed of liquid paraffin and TEOS, followed by dissolving paraffin with ethanol. The effects of various factors including the emulsifier structure and content, TEOS content, catalyst type, and the ethanol content in the continuous water phase on the particle size, shell thickness and morphology of the prepared hollow silica microspheres were studied in detail. The results show that the diffusion and contact of TEOS and water molecules as well as the hydrolysis condensation reaction of TEOS at the oil-water interface are two critical processes for the synthesis and morphological regulation of hollow silica microspheres. Cationic emulsifier with a hydrophobic chain of appropriate length is the prerequisite for the successful synthesis of hollow silica microspheres. The ethanol content in water phase is the dominant factor to determine the average diameter of hollow microspheres, which can vary from 96 nm to 660 nm with the increase of the volume ratio of alcohol-water from 0 to 0.7. The silica wall thickness varies with the content and the hydrophobic chain length of the emulsifier, TEOS content, and the activity of the catalyst. The component of the soft template will affect the morphology of the silica wall. When the liquid paraffin is replaced by cyclohexane, hollow microspheres with fibrous mesoporous silica wall are fabricated. This work not only enriches the basic theory of interfacial polymerization in the emulsion system, but also provides ideas and methods for expanding the morphology and application of hollow silica microspheres.

关键词： Hollow silica microspheres Emulsion template Morphology regulation mechanism Interfacial polymerization

Sequential expression of cyclooxygenase-2, glutamate receptor-2, and platelet activating factor receptor in rat hippocampal neurons after fluid percussion injury

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Neural Regeneration Research 2014年第9期9卷 978-985页

作者： Zhiqiang Li Qingming shu Lingzhi Li Maolin ge Yongliang Zhang Second Department of Medicine Inner Mongolia Corps Hospital Chinese People’s Armed Police Forces Department of Pathology General Hospital of Chinese People’s Armed Police Forces Section of Pharmaceutical Chemistry Department of Rescue Medicine Logistics University of Chinese People’s Armed Police Force Second Department of Surgery Inner Mongolia Corps Hospital Chinese People’s Armed Police Forces Training Department Logistics University of Chinese People’s Armed Police Force Tianjin Key Laboratory for Biomarkers of Occupational and Environmental Hazard

Traumatic brain injury causes gene expression changes in different brain regions. Occurrence and development of traumatic brain injury are closely related, involving expression of three factors, namely cyclooxygenase-2, glutamate receptor-2, and platelet activating factor receptor. However, little is known about the correlation of these three factors and brain neuronal injury. In this study, primary cultured rat hippocampal neurons were subjected to fluid percussion injury according to Scott’s method, with some modifications. RT-PCR and semi-quantitative immunocytochemical staining was used to measure the expression levels of cyclooxygenase-2, glutamate receptor-2, and platelet activating factor receptor. Our results found that cyclooxygenase-2 expression were firstly increased post-injury, and then decreased. Both mRNA and protein expression levels reached peaks at 8 and 12 hours post-injury, respectively. Similar sequential changes in glutamate receptor 2 were observed, with highest levels mRNA and protein expression at 8 and 12 hours post-injury respectively. On the contrary, the expressions of platelet activating factor receptor were firstly decreased post-injury, and then increased. Both mRNA and protein expression levels reached the lowest levels at 8 and 12 hours post-injury, respectively. Totally, our findings suggest that these three factors are involved in occurrence and development of hippocampal neuronal injury.

关键词： nerve regeneration brain injury platelet activating factor cyclooxygenase-2 RT-PCR immunocytochemistry hippocampus platelet activating factor receptor glutamate receptor 2 NSFC grant neural regeneration

Characteristics of transmitting channel wave in a coal seam

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Mining Science and Technology 2009年第3期19卷 331-336页

作者： YANG Zhen ge Mao-chen WANG shu-gang School of Mines China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China College of Earth and Mineral Scienc The Penn State University PA 16802 USA

An embedded underground coal seam carries channel waves of low seismic velocity along a stratigraphic rock-coal-rock *** a homogeneous and isotropic seam, seismic waves propagate as trapped waves within the seam, which leads to propagation of channel *** describe how to set up a field test for transmission in order to acquire channel waves in a coal *** channel wave signals are non-stationary in their frequencies and amplitudes, a necessary velocity spectrum and wavelet transformation analysis are applied to interpret the characteristics of channel *** advantage of using a wavelet transformation is that different resolutions can be obtained at different times and different *** to analysis of the seismic signals acquired in the S7 sensor hole, it was clearly shown that the characteristics of channel waves are lower frequencies and attenuation which can guide an effective wave for detecting voids, boundaries and faults in coal seams with strong roofs and floors.

关键词： in-seam seismic technique channel wave coal seam time-frequency domain Gabor wavelet velocity spectrum

Measurement of the fluidized velocity in gas-solid fluidized beds based on AE signal analysis by wavelet packet transform

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Science China Chemistry 2007年第2期50卷 284-289页

作者： WANG JingDai YANG YongRong ge PengFei shu WeiJie HOU LinXi Department of Chemical and Biochemical Engineering State Key Laboratory of Chemical EngineeringPolymer Reaction Engi-neering DivisionZhejiang UniversityHangzhou 310027China College of Chemical Engineering and Materials Science Ningbo UniversityNingbo 315211China

An energy distribution theory was presented based on regular evolvement of energy fraction of acous-tic signals with fluidization velocity. Wavelet packet analysis was used in processing the acoustic sig-nals originated from particle impact on the wall of a fluidized bed. A new criterion of judging incipient fluidization(Umf) velocity and minimum turbulent velocity(Umt) was proposed according to the energy distribution theory. Experiments were performed with five groups of high density polyethylene(PE) particles and one bimodal PE to acquire incipient fluidization velocity and minimum turbulent velocity by using the criterion. The feasibility of this method in obtaining characteristic fluidization parameters was further verified by comparing it to results from the pressure drop method and the empirical value from industry.

关键词： fluidized bed minimum fluidization velocity minimum turbulent velocity acoustic emission wavelet packet transform

Fabricating polymer/HEA-hybrid topological lattice structure for enhanced mechanical properties

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Progress in Natural Science:Materials International 2022年第6期32卷 800-805页

作者： Wentao Zhang Zhongzheng Yao Sihan Zhang Sinan Liu Huiqiang ying Jiacheng ge shu Fu Yu Lou Xiang Li Zhenduo Wu He Zhu shuangqin Chen Si Lan Herbert Gleiter Institute of Nanoscience School of Materials Science and Engineering Nanjing University of Science and Technology School of Sciences Nanjing University of Science and Technology Center for Neutron Scattering and Physics Department City University of Hong Kong Dongguan Research Institute Shenzhen Research Institute City University of Hong Kong

Metamaterials such as architected lattice structures have aroused broad interest in being applied as mechanical supports for their lightweight and custom-shaped *** various prior efforts have been devoted,a multiscale fabrication of micro-nano lattice structures without penalizing the mechanical properties is still a challenging but highly desirable *** we put forward a strategy to produce a mechanically enhanced micro-nano lattice structure by conformally depositing a CoCrFeNiTi high-entropy alloy(HEA) coating layer onto a three-dimensional(3D) printed polymer *** template for the 3D printing employs a six-membered tricapped trigonal prism(6M-TTP) structure derived from a medium-range order structure motif in amorphous *** topological complexity of the 6M-TTP can substantially avoid the stress concentration by offering stress-release channels,while the HEA film incorporating with amorphous and nanocrystalline constituents can further reinforce the lattice architecture through its size hardening *** from the above,the fabricated polymer/HEA-hybrid lattice exhibits a high specific compressive strength(～0.055 MPa kg-1m3at a density below 500 kg m-3),a superior elastic recoverability(～70% recovery rate under>30% compression),an enhanced plasticity(40% strain) and a high specific modulus(0.135 MPa kg-1m3).Our strategy initiates a perspective way to fabricate multiscale micro-nano lattice structures with improved mechanical properties,which could be extended to widespread metamaterial research.

关键词： Nanocrystals

Decadal-scale variability of warm season temperature in Beijing over the past 2650 years

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Chinese Science Bulletin 2011年第22期56卷 2366-2370页

作者： DAI ying ZHANG Yan ge JunYi Key Laboratory of Cenozoic geology andEnvironment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A continuous record of surface temperature for the past 2650 years was obtained in an earlier study from a Beijing stalagmite based on sedimentary layer counting and thickness *** spectrum analysis,multi-taper and wavelet spectral analyses are used in this study to identify decadal-scale signals and their origins in this *** long-term cycles of solar origin identified in earlier studies,this record contains cycles that dominate temperature with periods of 102-70,66-50,31,25-22,19,15,12 and 9 *** 102-70,25-22,12 and 9 year cycles are attributable to solar variation,while the others are likely to be related to low-latitude ocean *** results suggest that century-scale changes in the Beijing summer temperature over the past 2650 years are primarily controlled by solar variation,while ocean-atmospheric interactions play a prominent role in modu-lating decadal-scale variability.

关键词：年代际北京变异气温季节温暖表面温度太阳变化

Accelerometer error estimation and compensation for three-axis gyro-stabilized camera mount based on proportional multiple-integral observer

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Science China(Technological Sciences) 2014年第12期57卷 2387-2395页

作者： LI shu Sheng ZHONG Mai ying ZHAO Yan School of Instrument Science & Opto-engineering Beihang University

This paper deals with the problem of accelerometer error estimation and compensation for a three-axis gyro-stabilized camera mount. In a dynamic environment, the aircraft motion acceleration affects the accelerome ：er output and causes a degradation of attitude steady accuracy. In order to improve control accuracy, this paper proposes a proportional multiple-integral observer- based control strategy to estimate and compensate the accelerometer error. The basic idea of this paper is to approximate the error property by using a q-order polynomial function and extend the error and its derivatives as augmented states. Then a proportional multiple-integral observer is developed to estimate the error, with which the relationship between the error and the imbalance torque is formulated. The estimated value is compared to an angle threshold, the result of which is used to compen- sate the accelerometer output. Through static and vehicle-mounted experiments, it is demonstrated that compared with the tra- ditional method, the proposed method can improve the attitude steady accuracy effectively.

关键词： three-axis gyro-stabilized camera mount accelerometer error estimation and compensation proportional multiple-integralobserver imbalance torque