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Rare Metals 2022年第11期41卷 3677-3683页

作者： xing-nan Hao Xia Liu Department of Engineering Mechanics Beijing University of TechnologyBeijing100124China

The fabrication of graphene/metal matrix composites by selective laser sintering(SLS)technique has been extensively studied;however,the complex micros truc ture and residual stress limit their further ***,the sinterin... 详细信息

关键词： stress residual composites

Multidecadal Trends in Large-Scale Annual Mean SATa Based on CMIP5 Historical Simulations and Future Projections

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Engineering 2017年第1期3卷 136-143页

作者： nan xing Jianping Li Lanning Wang College of Global Change and Earth System Science Beijing Normal University Belting 100875 China Belting Meteorological Observatory Belting 100089 China Joint Center for Global Change Studies Beijing 100875 China

Based on observations and Coupled Model lntercomparison Project Phase 5 （CMIP5） results, multidecadal variations and trends in annual mean surface air temperature anomalies （SATa） at global, hemispheric, and hemispheric land and ocean scales in the past and under the future scenarios of two representative concentration pathways （RCPs） are analyzed. Fifteen models are selected based on their performances in capturing the temporal variability, long-term trend, multidecadal variations, and trends in global annual mean SATa. Observational data analysis shows that the multidecadal variations in annual mean SATa of the land and ocean in the northern hemisphere （NH） and of the ocean in the southern hemisphere （SH） are similar to those of the global mean, showing an increase during the 1900-1944 and 1971-2000 periods, and flattening or even cooling during the 1945-1970 and 2001-2013 periods. These observed characteristics are basically reproduced by the models. However, SATa over SH land show an increase during the 1945-1970 period, which differs from the other hemispheric scales, and this feature is not captured well by the models. For the recent hiatus period （2001-2013）, the projected trends of BCC-CSM1-1-m, CMCC-CM, GFDL-ESM2M, and NorESM1-ME at the global and hemispheric scales are closest to the observations based on RCP4.5 and RCP8.5 scenarios, suggesting that these four models have better projection capability in SATa. Because these four models are better at simulating and projecting the multidecadal trends of SATa, they are selected to analyze future SATa variations at the global and hemispheric scales during the 2006-2099 period. The selected multi-model ensemble （MME） projected trends in annual mean SATa for the globe, NH, and SH under RCP4.5 （RCP8.5） are 0.17 （0.29） ℃, 0.22 （0.36） ℃, and 0.11 （0.23） ℃-decade-1 in the 21st century, respectively. These values are significantly lower than the projections of CMIP5 MME without model selection.

关键词： Surface air temperature anomalies (SATa) Multidecadal trend Coupled Model lntercomparison Project Phase 5 (CMIPS) Projection

Partial embolization as re-treatment of hypersplenism after unsuccessful splenic artery ligation

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World Journal of Gastroenterology 2015年第4期21卷 1365-1370页

作者： Zheng-Ju Xu Lian-Qiu Zheng xing-nan Pan Clinical Liver Center 180~(th) Hospital of the People’s Liberation Army

Ligation of splenic artery(LSA) is used for the treatment of liver cirrhosis with hypersplenism. However, hypersplenism is not significantly improved following LSA treatment in some cases, and there are few reports of retreatment of hypersplenism after LSA. We report the case of a47-year-old man with liver cirrhosis and hypersplenism who underwent LSA treatment, but did not significantly improve. Laboratory tests revealed severe leukocytopeniaand thrombocytopenia. Celiac computed tomography arteriogram and digital subtraction angiography revealed two compensatory arteries connected to the hilar splenic artery from the left gastro-epiploic artery and from the dorsal pancreatic artery. Partial splenic embolization(PSE) was performed through the compensatory arteries. As a result, the patient achieved partial splenic ischemic infarction, and white blood cell and platelet counts rose and remained in the normal range. PSE is an effective therapeutic modality for the retreatment of hypersplenism when other modalities have failed.

关键词： Hypersplenism Partial splenic embolization Splenic

Bone marrow-derived mesenchymal stem cell therapy for decompensated liver cirrhosis:A meta-analysis

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World Journal of Gastroenterology 2014年第38期20卷 14051-14057页

作者： xing-nan Pan Lian-Qiu Zheng Xiao-Huan Lai Clinical Liver Center 180th Hospital of People’s Liberation Army

AIM: To assess the efficacy and safety of bone marrow-derived mesenchymal stem cell (BM-MSC) in the treatment of decompensated liver cirrhosis.

关键词： Decompensated liver cirrhosis Bone marrow stem cell Transfusion Meta-analysis

A Theoretical Explanation of Anomalous Atmospheric Circulation Associated with ENSO Modoki during Boreal Winter

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Atmospheric and Oceanic Science Letters 2014年第4期7卷 352-357页

作者： xing nan LI Jian-Ping LI Yao-Kun State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences University of the Chinese Academy of Sciences College of Global Change and Earth System Science Beijing Normal University

Based on a linear model, the present study provides analytical solutions for ideal triple forcing sources similar to sea surface temperature anomaly （SSTA） pat- terns associated with El Nino-Southern Oscillation （ENSO） Modoki in winter. The ideal triple pattern is composed of an equatorially symmetric heat source in the middle and equatoriaUy asymmetric cold forcing in the southeast and northwest. The equatorially symmetric heat source excites low-level cyclonic circulation anomalies associated with Rossby waves in both hemispheres, while the northwest- ern and southeastern equatorially asymmetric cold sources induce low-level anomalous anticyclones associated with Rossby waves in the hemisphere where the forcing source is located. Low-level zonal winds converge toward the heat sources associated with Kelvin and Rossby waves. Due to unequal forcing intensity in the northwest and southeast, atmospheric responses around the equatorially symmetric forcing become asymmetric, and low-level cyclonic circulation anomalies in the Southern Hemisphere become greater than those in the Northern Hemisphere. Ascending （descending） flows coincide with heat （cold） sources, resulting in a double-cell structure over the regions of forcing sources. Ideal triple patterns similar to SSTA patterns associated with La Nina Modoki produce opposite atmospheric responses. The theoretical atmospheric responses are consistent with observed circulation anomalies associated with ENSO Modoki. Therefore, the theoretical solutions can explain the dynamics responsible for atmospheric circulation anomalies associated with ENSO Modoki events.

关键词： external forcing sources atmospheric responses ENSO Modoki

Forecast of equivalent clock correction and its application

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Forecast of equivalent clock correction and its application

Performance analysis of two RDSS positioning modes of BeiDou-3 system

第五届中国卫星导航学术年会

作者： xing nan HU Xiaogong CAO Yueling SU Ranran WU Xiaoli Beijing Research Institute of Telemetry Shanghai Astronomical Observatory Chinese Academy of Sciences Beijing Global Information Center of Application and Exploitation

ISBN: (纸本)9783642547393

Beidou Navigation Satellite System provides two kinds of services: basic navigation service and wide area differential service. To enhance the positioning accuracy, both services are challenged by orbit error reduction problem, especially during yaw‐steering mode. Besides basic information, additional parameters, such as satellite pseudorange differential correction, could efficiently correct satellite orbit error and clock error. However, since it needs to be calculated in real‐time, differential correction is only broadcast to authorized users. Through investigation of the historical record, we find that shortly （an hour） forecasting for differential correction is doable. We proposed two forecasting methods in this work, and tested them with real observation data. We find that positioning precision of basic navigation service could be efficiently improved with the forecasted differential correction, in some cases could even reach the level of wide area differential service.

关键词： Beidou Navigation Satellite System satellite pseudorange differential correction positioning accuracy

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Astrodynamics 2022年第3期6卷 317-327页

作者： Dongxia Wang Rui Guo nan xing Zhijun Liu Tianqiao Zhang Hui Ren Xiaojie Li Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Operation Control Department Beijing Satellite Navigation CenterBeijing 100094China Astronomy Department Beijing Normal UniversityBeijing 100875China

The BeiDou-3 global satellite navigation system(BDS-3)provides two radio determination satellite service(RDSS)positioning services for users,i.e.,the traditional RDSS(TRDSS)positioning of the BeiDou-2 regional satellite navigation system,and the comprehensive RDSS(CRDSS)positioning,which integrates the RDSS and radio navigation satellite *** published studies regarding the RDSS positioning service are few,we analyze and compare the performances of the two RDSS positioning ***,we systematically investigate the principles of the TRDSS and CRDSS positioning,and then analyze the evaluation methods in terms of their positioning accuracy,real time,and coverage ***,based on the BeiDou RDSS measured data,we evaluate the performances of the TRDSS and CRDSS *** with TRDSS positioning,CRDSS positioning exhibits the following:1)A significant increase in positioning accuracy,resulting in error improvement from 8 to 2 m and root mean square improvement from 3.13 to 0.85 m;in other words,the positioning error,constant deviation,and stability improve significantly.2)The real time reduces slightly from 1.1 to 1.8 ns,which is within the acceptable range.3)The coverage range expands from the areas of 62°E-145°E and 5°N-55°N to the areas of 50°E-170°E and 0°N-70°N,respectively.4)CRDSS positioning is not restricted by the constraints of the digital elevation database or the user elevation information and can thus solve the occlusion problem effectively.

关键词： TRDSS positioning CRDSS positioning positioning accuracy real time coverage range

Pd-based nanocatalysts for oxygen reduction reaction:Preparation,performance,and in-situ characterization

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Chinese Journal of Structural Chemistry 2023年第11期42卷 55-68页

作者： Guan-nan xing Di-Ye Wei Hua Zhang Zhong-Qun Tian Jian-Feng Li College of Materials State Key Laboratory of Physical Chemistry of Solid SurfacesMOE Key Laboratory of Spectrochemical Analysis and InstrumentationCollege of Chemistry and Chemical EngineeringiChEMFujian Key Laboratory of Advanced MaterialsXiamen UniversityXiamen361005China Shenzhen Research Institute of Xiamen University Shenzhen518000China

Electrochemical energy devices such as fuel cells have received extensive concern in recent ***,the commercial applications of fuel cells have been restricted by the slow kinetics of oxygen reduction reaction(ORR).Pd-based fuel cell catalysts are strong candidates for enhanced ORR activities,especially under alkaline ***,extensive exploration has been made to improve the performance of Pd-based nano-catalysts for oxygen reduction *** paper reviews the research progress of preparation,electrocatalytic performance,and in-situ characterization of various Pd-based oxygen reduction catalysts,from zero-dimensional nanoparticles,to one-dimensional nanowires,to two-dimensional nanosheets,and to Pd single-atom *** may provide some help for improving the activity of Pd-based catalysts and understanding the reaction mecha-nisms and structure-activity relationships.

关键词： Pd-based nanocatalyst Oxygen reduction reaction Electrocatalysis In-situ characterization

Hepato-protective effect of thymoquinone against acetaminophen induced liver injury is associated with regulation of JNK and AMPK signaling pathway

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中国药理学与毒理学杂志 2017年第10期31卷 1007-1008页

作者： Yong YANG Ting BAI Ji-xing nan Qing-gao ZHANG Medical College of Dalian University Dalian 116622 China Key Laboratory for Natural Resource of Changbai Mountain & Functional Molecules Ministry of Education College of Pharmacy Yanbian University Yanji 133002 China

OBJECTIVE To investigate the hepato-protective mechanism of thymoquinone(TQ) on the development of acetaminophen(APAP)-induced liver *** In vivo,male kunming mice were injected with a single dose of 300 mg·kg^(-1) *** mice were pretreated with TQ(5 or 20 mg·kg^(-1))and N-acetylcysteine(NAC,300 mg·kg^(-1))2 h before APAP *** were euthanized at 2 h,6 h,12 h after APAP *** vitro,human Chang liver cells were incubated with 3.125,6.25 or 12.5μmol·L^(-1) TQ,10μmol·L^(-1) SP600125 and 500μmol·L^(-1) AICAR in the presence of APAP for 24 *** viability were analyzed by MTT assay,protein expressions were assessed by Western *** TQ pretreatment significantly reduced serum aminotransferase and increased hepatic glutathione(GSH)and glutathione peroxidase(GSH-PX)activities,while significantly inhibited interleukin-1β(IL^(-1)β)*** significantly inhibited c-Jun N-terminal kinase(JNK),extracellular signal regulated kinase(ERK)and P38 phosphorylation induced by ***,TQ inhibited phosphatidylinositol 3-kinase(PI3K)/mammalian target of rapamycin(m TOR)signaling activation and activated AMPK phosphorylation induced by *** addition,TQ inhibited signal transducer and activator of transcription 3(STAT3)phosphorylation on APAP-induced liver *** vitro,APAP enhanced JNK phosphorylation and attenuated AMPK phosphorylation in Chang liver cel s,and these effects were blocked by pretreatment with TQ,SP600125(JNK inhibitor)and AICAR(AMPK activator).CONCLUSION Our findings suggest that TQ may actively prevent APAP-induced liver injury,and this effect may be mediated by JNK and AMPK signaling pathways.

关键词： thymoquinone acetaminophen liver injury c-Jun N-terminal kinase AMP-activated protein kinase

Studies on the mechanism of SIRT1/AMPK signaling pathway between hepatocytes and hepatic stellate cells

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中国药理学与毒理学杂志 2017年第10期31卷 954-955页

作者： Ting BAI Yong YANG Ji-xing nan Qing-gao ZHANG Medical College of Dalian University Dalian 116622 China Key Laboratory for Natural Resource of Changbai Mountain & Functional Molecules Ministry of Education College of Pharmacy Yanbian University Yanji 133002 China

OBJECTIVE To investigate the mechanism of SIRT1/AMPK signaling pathway between hepatocytes and hepatic stellate cells(HSCs).METHODS Normal human Chang liver cells and human hepatic stellate cell line,LX-2 cells were treated with SRT1720(10μmol·L^(-1))and AICAR(500μmol·L^(-1))prior to ethanol(50 mmol·L^(-1)) for 24 and 48 *** viability was analyzed by methyl thiazolyl tetrazolium ***1,AMPK and p-AMPK m RNA levels for 24 h and 48 h were analyzed by RT-PCR,SIRT1,AMPK and p-AMPK protein expressions in the supernatant at 24 and 48 h was detected by Western *** SRT1720 and AICAR effectively decreased LX-2 cell viabilities and exhibited scarcely little toxicity in human Chang liver ***1720 and AICAR attenuated collagen-I,α-smooth muscle actin(α-SMA)levels,activated liver kinase B-1(LKB1)and AMPK phosphorylation in ethanol treated LX-2 ***,SRT1720 and AICAR enhanced SIRT1 expression mediated by ethanol both in Chang liver cells and LX-2 ***,SRT1720 and AICAR suppressed the expression of sterol regulatory element-binding protein-1(SREBP-1)to regulate fatty acid *** SIRT1 agonist and AMPK agonist blocked the crosstalk between hepatocytes and HSCs via SIRT1/AMPK signaling pathway to modulate hepatocytes accumulation of lipid and HSCs activation.

关键词： hepatic stellate cells hepatocytes SIRT1 AMPK