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Preparation, characterization and electrochemical properties of mesoporous LiFe_(0.99)Mo_(0.01)PO_4/C

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Rare Metals 2009年第4期28卷 317-321页

作者： yu chunyang WANG Zhongli CHEN yu XIA Dingguo chu Wangsheng WU Ziyuc Biochemical Engineering College Beijing Union University Beijing 100023 China College of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

A mesoporous LiFe0.99Mo0.01PO4/C composite was synthesized by the sol-gel method using （NH4）2MoO4 as a doping starting material. The formation of conductive carbon, metal doping and mesopores was achieved simultaneously in the prepared material. The characterizations of crystal structures and microstructures were investigated using X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, extended X-ray-absorption fine-structure （EXAFS） and X-ray-absorption near-structure spectroscopy （XANES） while the surface area was determined using N2 adsorption techniques. Cyclic voltammetry （CV） and charge-discharge cycling performance were used to characterize its electrochemical properties. The sample possessed uniformly distributed mesopores with an average pore size of 4 nm, and the specific surface area was about 69.368 m^2/g. The results show that the reversible capacity of mesoporous LiFe0.99Mo0.01PO4/C is about 160 mAh/g at 0.1C, 135 mAh/g at 1C and 90 mAh/g at 5C, respectively. The capacity fading is neglectable.

关键词： lithium ion battery cathode material mesoporous composite electrochemical properties

Bioinspired Underwater Navigation Using Polarization Patterns Within Snell’s Window

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China Ocean Engineering 2023年第4期37卷 628-636页

作者： CHENG Hao-yuan yu Shi-min yu Hao ZHU Jin-chi chu Jin-kui Department of Mechanical and Electrical Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Ocean University of ChinaQingdao 266100China Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian 116024China

Aiming at the requirement of autonomous navigation capability of the underwater unmanned vehicle(UUV),a novel bionic method for underwater navigation based on polarization pattern within Snell’s window is *** by creatures,polarization navigation is a satellite-free navigation scheme and has great potential to be used in the ***,because of the complex underwater environment,whether UUV polarization navigation can be realized is *** illustrate the feasibility of underwater polarization navigation,we firstly establish the model of under-water polarization patterns to prove the stability and predictability of the underwater polarization pattern within Snell’s ***,we carry out static and dynamic experiments of underwater heading determination based on developed polarization information detection ***,we obtain underwater polarization patterns and conduct the tracking experiment at different water *** experimental results of the underwater polarization patterns are consistent with the simulation,which proves the correctness of the proposed *** the water depth of 5 m,the average angle and position error of the tracking experiment are 14.3508°and 4.0812 m,*** is illustrated that underwater polarization navigation is realizable and the precision can meet the real-time navigation requirements of *** study promotes the improvement of underwater navigation ability and the development of marine equipment.

关键词： underwater navigation polarization pattern heading determination tracking experiment

The Assessment of Ocean Wave Energy Along the Coasts of Taiwan

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China Ocean Engineering 2012年第3期26卷 413-430页

作者： LIN yu-Hsien FANG ming-chung Fishing Boat & Mar.Eng.Research Center National Cheng-Kung University Dept.of Systems & Naval Mechatronic Eng. National Cheng-Kung University

The wave energy resource around the coasts of Taiwan is investigated with wave buoy data covering a 3-year period （2007-2009）. Eleven study sites within the region bounded by the 21.5^°N-25.5°N latitudes and 118°E-122°E longitudes are selected for analysis. The monthly moving-average filter is used to obtain the low-frequency trend based on the available hourly data. After quantifying the wave power and annual wave energy, the substantial resource is the result of Penghu buoy station, which is at the northeastern side of Penghu Island in the Taiwan Strait. it is investigated that the Penghu sea area is determined to be the optimal place for wave energy production according to its abundant resource of northeasterly monsoon waves, sheltering of the Taiwan Island, operation and maintenance in terms of seasonal conditions, and constructability of wave power devices.

关键词： ocean wave energy wave energy converter wave climate Taiwan Strait monsoon waves

Atomic-level insights into the initial oxidation mechanism of high-entropy diborides by first-principles calculations

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Journal of Materiomics 2024年第2期10卷 423-430页

作者： Yiwen Liu Hulei yu Hong Meng Yanhui chu School of Materials Science and Engineering South China University of TechnologyGuangzhou510641China

Understanding the initial oxidation mechanism is critical for studying the oxidation resistance of high-entropy ***,related studies are ***,the initial oxidation mechanism of(Zr_(0.25)Ti_(0.25)Nb_(0.25)Ta_(0.25))B_(2)high-entropy diborides(HEB_(2)-1)is investigated by first-principles calculations at the atomic *** employing the two-region model method,the most stable surface of HEB_(2)-1 is determined to be(1120)*** dissociative adsorption process of the oxygen molecule on the HEB_(2)-1-(1120)surface is predicted to proceed spontaneously,where OeO bond breaks and each oxygen atom is chemisorbed on the most preferable hollow *** adsorption energy and the diffusion barrier of the oxygen atom on the(1120)surface of HEB_(2)-1 are in the vicinity of the average level of the cor-responding four individual *** addition,ab initio molecular dynamics simulations indicate a high initial oxidation resistance of HEB_(2)-1 at 1000 *** results are beneficial to further designing the high-entropy diborides with excellent oxidation resistance.

关键词： High-entropy diborides Oxidation First-principles calculations

Controllable Synthesis of CaCO_3 Micro/Nanocrystals with Different Morphologies in Microemulsion

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Chemical Research in Chinese Universities 2010年第5期26卷 678-682页

作者： yu Dong chu Ying DONG Li-hong ZHUO yu-jiang Department of Chemistry Northeast Normal University Changchun 130024 P. R. China Elementary Normal College Dalian University Dalian 116300 P. R. China

Lens-like vaterite CaCO3 microrings composed of CaCO3 nanoparticles were synthesized via a microemulsion-mediated route at room temperature with ethanol and n-hexanol as co-surfactant. This process did not demand any additional energy such as heating or continuous agitation. It was the first time to use ethanol as co-surfactant in the synthesis of micro or nanomaterials. And the ethanol was believed to play an important role in the aggregation fashion of CaCO3 nanoparticles. Moreover, shuttle-shaped nanorods, hexagonal nanoplates, and rice-like nanoparticles were also fabricated by modulating the growth parameters. Additionally, the introduce of ethanol into microemulsions as co-surfactant may be generalized as a novel green route to control the structure of other functional materials.

关键词： CaCO3 Microring Cosurfactant

Power spectral properties of the soft spectral states in four black hole transients

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Research in Astronomy and Astrophysics 2021年第7期21卷 143-154页

作者： Dong-ming Mao Wen-Fei yu Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China

The X-ray variability in the soft X-ray spectral state of black hole binaries is primarily characterized by a power-law noise(PLN), which is thought to originate from the propagation of the modulation in the mass accretion rate of a standard accretion disk flow. Such a PLN has also been revealed in the disk spectral component in the hard and the intermediate states in several black hole binaries. Here we present an investigation of the Rossi X-ray Timing Explorer(RXTE) observations of four black hole transients in which soft spectral states were observed twenty times or more. We show that in the soft spectral state, the PLN index varied in a large range between –1.64 and –0.62, and the fractional rms variability calculated in the 0.01 – 20 Hz frequency range reached as large as 7.67% and as low as 0.83%. Remarkably,we have found evidence of an inclination dependence of the maximal fractional rms variability, the averaged fractional rms variability and the fractional rms variability of the median in the sample based on current knowledge of inclination of black hole binaries. An inclination dependence has only been predicted in early magnetohydrodynamic simulations of isothermal disks limited to a high-frequency regime. In theory,the noise index is related to the physics of inward propagation of disk fluctuations, while the fractional rms amplitude reflects the intrinsic properties of the magnetohydrodynamic nature of the accretion *** results therefore suggest that X-ray variability in the soft state can be used to put constraints on the properties of the accretion flow as well as the inclination of the accretion disk.

关键词： X-rays:general X-rays:binaries X-rays:individual:4U 1630-47 H 1743-322 XTE J1817-330 XTE J1859+226

Up-Regulation of Trem2 Inhibits Hippocampal Neuronal Apoptosis and Alleviates Oxidative Stress in Epilepsy via the PI3K/Akt Pathway in Mice

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Neuroscience Bulletin 2019年第3期35卷 471-485页

作者： Ai-Hua Liu Min chu yu-Ping Wang Department of Neurology Xuanwu Hospital Capital Medical University

Epilepsy is a chronic and severe neurological disorder that has negative effects on the autonomous activities of patients. Functionally, Trem2(triggering receptor expressed on myeloid cells-2) is an immunoglobulin receptor that affects neurological and psychiatric genetic diseases. Based on this rationale, we aimed to assess the potential role of Trem2 integration with the PI3 K/Akt pathway in epilepsy. We used microarray-based gene expression profiling to identify epilepsy-related differentially-expressed genes. In a mouse hippocampal neuron model of epilepsy, neurons were treated with lowMg^2+ extracellular fluid, and the protein and mRNA expression of Trem2 were determined. Using a gain-offunction approach with Trem2, neuronal apoptosis and its related factors were assessed by flow cytometry, RT-qPCR,and Western blot analysis. In a pilocarpine-induced epileptic mouse model, the malondialdehyde(MDA) and8-hydroxy-20-deoxyguanosine(8-OHdG) content and superoxide dismutase(SOD) and glutathione-peroxidase(GSH-Px) activity in the hippocampus were determined,and the protein expression of Trem2 was measured. In addition, the regulatory effect of Trem2 on the PI3 K/Akt pathway was analyzed by inhibiting this pathway in both the cell and mouse models of epilepsy. Trem2 was found to occupy a core position and was correlated with ***2 was decreased in the hippocampus of epileptic miceand epileptic hippocampal neurons. Of crucial importance,overexpression of Trem2 activated the PI3 K/Akt pathway to inhibit neuronal apoptosis. Moreover, activation of the PI3 K/Akt pathway through over-expression of Trem2 alleviated oxidative stress, as shown by the increased expression of SOD and GSH-Px and the decreased expression of MDA and 8-OHdG. The current study defines the potential role of Trem2 in inhibiting the development of epilepsy, indicating that Trem2 up-regulation alleviates hippocampal neuronal injury and oxidative stress, and inhibits neuronal apoptosis in epilepsy

关键词： Trem2 Epilepsy Neuronal apoptosis PI3K/Akt pathway Oxidative stress

Machine learning in materials science

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InfoMat 2019年第3期1卷 338-358页

作者： Jing Wei Xuan chu Xiang-yu Sun Kun Xu Hui-Xiong Deng Jigen Chen Zhongming Wei ming Lei State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijingChina State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesCenter of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of SciencesBeijingChina Zhejiang Provincial Key Laboratory for Cutting Tools Taizhou UniversityTaizhouChina Beijing Academy of Quantum Information Sciences BeijingChina

Traditional methods of discovering new materials,such as the empirical trial and error method and the density functional theory(DFT)-based method,are unable to keep pace with the development of materials science today due to their long development cycles,low efficiency,and high ***,due to its low computational cost and short development cycle,machine learning is coupled with powerful data processing and high prediction performance and is being widely used in material detection,material analysis,and material *** this article,we discuss the basic operational procedures in analyzing material properties via machine learning,summarize recent applications of machine learning algorithms to several mature fields in materials science,and discuss the improvements that are required for wide-ranging application.

关键词： data processing deep learning machine learning modeling validation

Scorpiones,Scolopendra and Gekko Inhibit Lung Cancer Growth and Metastasis by Ameliorating Hypoxic Tumor Microenvironment via PI3K/AKT/mTOR/HIF-1αSignaling Pathway

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Chinese Journal of Integrative Medicine 2024年第9期30卷 799-808页

作者： MAO Qi-yuan WANG Xue-qian LIN Fei yu ming-wei FAN Hui-ting ZHENG Qi LIU Lan-chun ZHANG chu-chu LI Dao-rui LIN Hong-sheng Department of Oncology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China Department of Oncology Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing100010China Department of Cardiology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China Institute of Traditional Chinese Medicine Information China Academy of Chinese Medical SciencesBeijing100700China

Objective:To investigate whether Buthus martensii karsch(Scorpiones),Scolopendra subspinipes mutilans ***(Scolopendra)and Gekko gecko Linnaeus(Gekko)could ameliorate the hypoxic tumor microenvironment and inhibit lung cancer growth and metastasis by regulating phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α(PI3K/AKT/mTOR/HIF-1α)signaling ***:Male C57BL/6J mice were inoculated with luciferase labeled LL/2-luc-M38 cell suspension to develop lung cancer models,with rapamycin and cyclophosphamide as positive *** methyl cellulose solutions of Scorpiones,Scolopendra and Gekko were administered intragastrically as 0.33,0.33,and 0.83 g/kg,respectively once daily for 21 *** expression were detected every 7 days after inoculation,and tumor growth curves were *** was performed to determine CD31 and HIF-1αexpressions in tumor tissue and microvessel density(MVD)was *** blot was performed to detect the expression of PI3K/AKT/mTOR/HIF-1αsignaling pathway-related ***-linked immunosorbent assay was performed to detect serum basic fibroblast growth factor(bFGF),transforming growth factor-β1(TGF-β1)and vascular endothelial growth factor(VEGF)in ***:Scorpiones,Scolopendra and Gekko prolonged the survival time and inhibited lung cancer metastasis and expression of HIF-1α(all P<0.01).Moreover,Scorpiones,Scolopendra and Gekko inhibited the phosphorylation of AKT and ribosomal protein S6 kinase(p70S6K)(P<0.05 or P<0.01).In addition,they also decreased the expression of CD31,MVD,bFGF,TGF-β1 and VEGF compared with the model group(P<0.05 or P<0.01).Conclusion:Scorpiones,Scolopendra and Gekko all showed beneficial effects on lung cancer by ameliorating the hypoxic tumor microenvironment via PI3K/AKT/mTOR/HIF-1αsignaling pathway.

关键词： Scorpiones Scolopendra Gekko dredging collaterals and activating blood Chinese medicine of worms lung cancer hypoxic tumor microenvironment phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α signaling pathway