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Thermal-sprayed coating of optimally mixed ceramic powders on stainless steel with enhanced corrosion resistance

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Journal of Iron and Steel Research International 2018年第2期25卷 207-212页

作者： Ping-hu Chen Zhi-lin liu Rui-qing li Chang-jun Qiu xiao-qian li College of Mechanical and Electrical Engineering CentralSouth University Changsha 410083 Hunan China State Key Laboratory of High Performance ComplexManufacturing Central South University Changsha 410083Hunan China light Alloy Research Institute Central South UniversityChangsha 410083 Hunan China College of Mechanical Engineering University of SouthChina Hengyang 421001 Hunan China

Three different groups of ceramic powders for the thermal-swayed coating were firstly prepared using sintering and ball milling. Then, these powders were separately deposited on three stainless steel substrates, followed by individual corrosion resistance examination. Microstructural characterization showed that the levels of micro-void and micro-crack at the bonding interface （between coating and substrate） depended on the proportions of different ceramic particles. Meanwhile, a significantly enhanced corrosion resistance was reproducibly observed in one group of as-coated samples that have the optimal combination of given ceramic powders. Furthermore, the mechanism of corresponding enhanced corrosion resistance was discussed. It was found that the optimal ceramic powders for the present thermal-sprayed coating should contain 30.2 wt% SiO2, 54 wt% Cr2O3, 6.8 wt% Al2O3, 4.8 wt% CaO and 1.8 wt% TiO2. The corrosion velocities of such samples in the 3.5 vol.% HCl, 15 wt% NaOH and 5 wt% NaCl solutions were 3.74, 2.98 and 0.50 g h-1 m-2 for 168, 336 and 336 h, respectively.

关键词： Ceramic powder Thermal-sprayed coating Bonding interface Corrosion resistance

Effective Response of Nonlinear Spherical Coated Composites Under External AC and DC Electric Field

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Communications in Theoretical Physics 2009年第4期51卷 743-747页

作者： SHEN Yu-Yan CHEN xiao-Gang li qian-qian CUI Wei HAO Yan-Hua College of Science Inner Mongolia University of Technology Hohhot 010051 China

Under the external AC and DC electric field, the effective response of nonlinear spherical coated composites, which obey the constitutive relation of electric displaeement and electric field, is investigated in the dilute limit by using the perturbation method. The local potentials in inclusion and host regions are derived at all harmonics. Moreover, the formulae of the effective linear and nonlinear responses are given in the dilute limit.

关键词： nonlinear composites effective response AC electric field

Asymmetric migration dynamics of the tropical Asian and Australasian floras

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Plant Diversity 2023年第1期45卷 20-26页

作者： li-Guo Zhang xiao-qian li Wei-Tao Jin Yu-Juan liu Yao Zhao Jun Rong xiao-Guo Xiang Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity Institute of Life Science and School of Life SciencesNanchang UniversityNanchang.Jiangxi330031China State Key Laboratory of Systematic and Evolutionary Botany Chinese Academy of SciencesBeijing.100093China

The tropical Asian and Australasian floras have a close relationship,and is a vital distribution pattern of seed plants *** estimated,more than 81 families and 225 genera of seed plants distributed between tropical Asia and ***,the evolutionary dynamics of two floras were still ***,a total of 29 plant lineages,represented the main clades of seed plants and different habits,were selected to investigate the biotic interchange between tropical Asia and Australasia by integrated dated phylogenies,biogeography,and ancestral state *** statistics indicated that 68 migrations have occurred between tropical Asia and Australasia since the middle Eocene except terminal migrations,and the migration events from tropical Asia to Australasia is more than 2 times of the *** 12 migrations occurred before 15 Ma,whereas the remaining56 migrations occurred after 15 *** number of potential dispersal events(MDE) analysis also shows obvious asymmetry,with southward migration as the main feature,and indicates the climax of bi-directional migrations occurred after 15 *** speculate that the formation of island chains after the Australian-Sundaland collision and climate changes have driven seed plant migrations since the middle ***,biotic dispersal and stable habitat may be crucial for floristic interchange between tropical Asia and Australasia.

关键词： Tropical Asia-Australasia Floristic interchange Biogeography Dispersal Seed plants

Microstructure,mechanical properties,and wear resistance of VCp-reinforced Fe-matrix composites treated by Q&P process

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International Journal of Minerals,Metallurgy and Materials 2018年第9期25卷 1060-1069页

作者： Ping-hu Chen Yi-bo li Rui-qing li Ri-peng Jiang Song-sheng Zeng xiao-qian li College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Changsha 410083China light Alloy Research Institutes Central South UniversityChangsha 410083China Valin ArcelorMittal Automotive Steel Co. Ltd.Loudi 417000China

A quenching and partitioning(Q&P) process was applied to vanadium carbide particle(VCp)-reinforced Fe-matrix composites(VC-Fe-MCs) to obtain a multiphase microstructure comprising VC, V8 C7, M3 C, α-Fe, and γ-Fe. The effects of the austenitizing temperature and the quenching temperature on the microstructure, mechanical properties, and wear resistance of the VC-Fe-MCs were studied. The results show that the size of the carbide became coarse and that the shape of some particles began to transform from diffused graininess into a chrysanthemum-shaped structure with increasing austenitizing temperature. The microhardness decreased with increasing austenitizing temperature but substantially increased after wear testing compared with the microhardness before wear testing; the microhardness values improved by 20.0% ± 2.5%. Retained austenite enhanced the impact toughness and promoted the transformation-induced plasticity(TRIP) effect to improve wear resistance under certain load conditions.

关键词： vanadium carbide Fe-matrix composites quenching and partitioning process transformation-induced plasticity effect microhardness impact toughness wear resistance

The roles of microRNAs in spinal cord ischemia-reperfusion injury

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Neural Regeneration Research 2022年第12期17卷 2593-2599页

作者： Feng-Shou Chen Xiang-Yi Tong Bo Fang Dan Wang xiao-qian li Zai-li Zhang Department of Anesthesiology the First Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

Spinal cord ischemia/reperfusion injury is a devastating medical disorder with poor prognosis that is associated with several pathophysiological ***,multiple stimuli can trigger SCII,so the underlying mechanism of this pathology has not yet been fully ***(miRNAs)are a class of non-coding RNAs that mediate a variety of nervous system diseases and regulate numerous physiological functions,including apoptosis,autophagy,inflammation,and blood-spinal cord barrier *** expression profiles are known to be altered after spinal cord ischemia/reperfusion ***,gaining a better understanding of the significant roles that miRNAs play in spinal cord ischemia/reperfusion injury could help develop potential preventive and therapeutic strategies for spinal cord ischemia/reperfusion *** review summarizes the current state of our knowledge about the relationship between miRNAs and spinal cord ischemia/reperfusion injury,as well as potential miRNAs that could be targeted to treat spinal cord ischemia/reperfusion injury.

关键词： apoptosis autophagy blood-spinal cord barrier inflammation microRNAs pathophysiology review spinal cord ischemia-reperfusion injury

Effect of Preparation Methods on Hydriding Properties of La1.5Mg17 Ni0.5 Composite Materials

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Journal of Rare Earths 2004年第Z2期22卷 110-113页

作者： Jiang lijun xiao Fang li qian lin Qin Zhan Feng Chou Kouchih Lei Tingquan General Research Institute for Non-Ferrous Metal Beijing 100088China Department of Material Science and Engineering Harbin Institute of TechnologyHarbin 150001China General Research Institute for Non-Ferrous MetalBeijing 100088China Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China General Research Institute for Non-Ferrous MetalBeijing 100088China Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China Department of Material Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

La1.5Mg17Ni0.5 hydrogen storage materials were prepared by hydriding combustion synthesis (HCS) and mechanical alloying (MA) method respectively. The experimental results show that the hydrogen absorption properties of La1.5Mg17Nio.5 prepared by MA are better than that by HCS. La1.5Mg17Nio.5 prepared by MA can absorb 6.73 mass% hydrogen at 523 K within 1 min, and 4.92 mass% hydrogen at 423 K. The improvement of hydriding properties of La1.5Mg17Ni0.5alloy prepared by MA can be ascribed to the formation of nano-crystalline and defects during the mechanical alloying.

关键词： hydriding combustion synthesis mechanical alloying hydrogen storage material hydriding property

Assembly dynamics of East Asian subtropical evergreen broadleaved forests: New insights from the dominant Fagaceae trees

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Journal of Integrative Plant Biology 2022年第11期64卷 2126-2134页

作者： lisi Hai xiao-qian li Jing-Bo Zhang xiao-Guo Xiang Rui-Qi li Florian Jabbour Rosa del COrtiz An-Ming Lu Zhi-Duan Chen Wei Wang State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity Institute of Life Science and School of Life SciencesNanchang UniversityNanchang 330031China Institut de Systématique EvolutionBiodiversité(ISYEB)Muséum national d'Histoire naturelleCNRSSorbonne UniversitéEPHEUniversitédes AntillesParis 75005France Missouri Botanical Garden St.LouisMissouri 63166‐0299USA

The dominant species of a biome can be regarded as its genuine *** broadleaved forests(EBLFs) in subtropical East Asia harbor high levels of species biodiversity and endemism and are vital to regional carbon storage and ***,the historical assembly of this unique biome is still *** is the most essential family in East Asian subtropical EBLFs and its dominant species are vital for the existence of this ***,we used the dominant Fagaceae species to shed light on the dynamic process of East Asian subtropical EBLFs *** results indicate high precipitation in summer and low temperature in winter are the most influential climatic factors for the distribution of East Asian subtropical *** East Asian subtropical EBLFs did not begin to appear until 23 Ma,subsequently experienced a longlasting development in the Miocene and markedly deteriorated at about 4 Ma,driven jointly by orogenesis and *** also document that there is a lag time between when one clade invaded the region and when its members become dominant species within the *** study may improve our ability to predict and mitigate the threats to biodiversity of East Asian subtropical EBLFs and points to a new path for future studies involving multidisciplinary methods to explore the assembly of regional biomes.

关键词： biome climate change dominant species East Asia ecological niche modeling phylogeny

Proliferation Inhibitory Activity of Quinones from Blaps rynchopetera Defense Secretion on Colorectal Tumor Cells

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Chinese Journal of Integrative Medicine 2023年第8期29卷 683-690页

作者： qian xiao-li Meng Di liU Heng liU Chao-he ZHOU Ping YANG Yin-he WANG Jia-peng xiao Huai DING Zhong-tao Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D DaliYunnan Province(671003)China College of Pharmacy Dali UniversityDaliYunnan Province(671003)China Functional Molecules Analysis and Biotransformation Key Laboratory of Universities in Yunnan Province Kunming(650091)China

Objective: To explore the proliferation inhibitory effect of quinones from Blaps rynchopetera defense secretion on colorectal tumor cell lines. Methods: Human colorectal cancer cell HT-29, human colorectal adenocarcinoma cell Caco-2 and normal human colon epithelial cell CCD841 were chosen for the evaluation of inhibitory activity of the main quinones of B. rynchopetera defense secretion, including methyl p-benzoquinone(MBQ), ethyl p-benzoquinone(EBQ), and methyl hydroquinone(MHQ), through methyl thiazolyl tetrazolium assay. The tumor-related factors, cell cycles, related gene expressions and protein levels were detected by enzyme-linked immunosorbent assy, flow cytometry, RT-polymerase chain reaction and Western blot, respectively. Results: MBQ, EBQ, and MHQ could significantly inhibit the proliferation of Caco-2, with half maximal inhibitory concentration(IC50) values of 7.04±0.88, 10.92±0.32, 9.35±0.83, HT-29, with IC50values of 14.90±2.71, 20.50±6.37, 13.90±1.30, and CCD841, with IC50values of 11.40±0.68, 7.02±0.44 and 7.83±0.05 μg/mL, respectively. Tested quinones can reduce the expression of tumor-related factors tumor necrosis factor α, interleukin(IL)-10, and IL-6 in HT-29 cells, selectively promote apoptosis, and regulate the cell cycle which can reduce the proportion of cells in the G1phase and increase the proportion of the S ***, tested quinones could up-regulate mRNA and protein expression of GSK-3β and APC, while down-regulate that of β-catenin, Frizzled1, c-Myc, and CyclinD1 in the Wnt/β-catenin pathway of HT-29 ***: Quinones from B. rynchopetera defense secretion could inhibit the proliferation of colorectal tumor cells and reduce the expression of related factors, which would be functioned by regulating cell cycle, selectively promoting apoptosis, and affecting Wnt/β-catenin pathway-related mRNA and protein expressions.

关键词： Blaps rynchopetera Chinese medicine quinones anti-colorectal tumor Wnt/β-catenin pathway

Expression,purification and serological analysis of hepatocellular carcinoma associated antigen HCA587 in insect cells

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World Journal of Gastroenterology 2003年第4期9卷 678-682页

作者： Bing li Hong-Yan Wu xiao-Ping qian Yan li Wei-Feng Chen Immunology Department of Peking University Health Science Center,Beijing,100083,China Immunology Department of Peking University Health Science Center 38 Xueyuan Road Beijing 100083 China. wfchen@***

AIM: In order to assess hepatocellular carcinoma associated antigen HCA587 as a potential target for immunotherapy,the Bac-to-Bac expression system was used to express recombinant protein HCA587 in insect ***: The cDNA encoding HCA587 gene was cloned into donor vector pFasBacHtb and recombinant pFasBac Htb587 was transformed into competent cells *** Bacmid-587 was transfected into Sf9 insect cells using CELLFECTIN, Recombinant HCA587 protein was produced in Sf9 insect cells after infection with recombinant baculovirus, and was purified using Ni-NTA resin. Sera from HCC patients were also screened using recombinant protein ***: The molecular weight of the recombinant protein HCA587 expressed in insect cells was approximately *** blot results proved the recombinant protein HCA587had the similar antigenicity with its native *** analysis told that the rate of seroreactivity to HCA587 was not high in HCC ***: The recombinant protein HCA587 was successfully expressed and purified using Bac-to-Bac expression system. It paved the way for generation of specific antibody and investigation of immunohistochemical analysis and immune responses of HCC in the future.

关键词： HCA587抗原肝细胞癌血清学检查免疫疗法免疫组织化学