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    题名 作者 年代 出处 被引量
1Hybridizing grey wolf optimization with differential evolution for global optimization and test scheduling for 3D stacked SoC显示文摘A new meta-heuristic method is proposed to enhance current meta-heuristic methods for global optimization and test scheduling for three-dimensional(3D) stacked system-on-chip(SoC) by hybridizing grey wolf optimization with differential evolution(HGWO). Because basic grey wolf optimization(GWO) is easy to fall into stagnation when it carries out the operation of attacking prey, and differential evolution(DE) is integrated into GWO to update the previous best position of grey wolf Alpha, Beta and Delta, in order to force GWO to jump out of the stagnation with DE's strong searching ability. The proposed algorithm can accelerate the convergence speed of GWO and improve its performance.Twenty-three well-known benchmark functions and an NP hard problem of test scheduling for 3D SoC are employed to verify the performance of the proposed algorithm. Experimental results show the superior performance of the proposed algorithm for exploiting the optimum and it has advantages in terms of exploration.Aijun Zhu Chuanpei Xu Zhi Li Jun Wu Zhenbing Liu 2015Journal of Systems Engineering and Electronics2015,26,2:83
2Numerical Simulation on Climate Effects of Freezing-Thawing Processes Using CCM3显示文摘A parameterization of soil freezing-thawing physics for use in the land-surface model of the National Center for Atmospheric Research(NCAR) Community Climate Model(CCM3) is developed and evaluated.The new parameterization scheme has improved the representation of physical processes in the existing land surface model.Numerical simulations using CCM3 with improved land-surface processes and with the original land-surface processes are compared against the NCEP reanalysis.It is found that the CCM3 version using the improved land surface model shows significant improvements in simulating precipitation in China during the summer season,the general circulation over East Asia,and wind fields over the Tibet Plateau.For the summer season,the improved model was able to better simulate the Indian summer monsoon components,including the mean northerly wind in the upper troposphere and mean southerly wind in the lower troposphere.Chenghai Wang1,2*,Guodong Cheng3,Aijun Deng4,Wenjie Dong5 1.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 2.State Key Laboratory of Cryosphere Sciences,Cold and Arid Regions Environmental and Engineering Research Insti-tute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 3.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 4.Department of Meteorology,The Pennsylvania State University,University Park,PA 16802 5.State Key Laboratory of Earth Surface Processes and Ecology Resource,Beijing Normal University,Beijing 100875,China Chenghai Wang1,2*,Guodong Cheng3,Aijun Deng4,Wenjie Dong5 1.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 2.State Key Laboratory of Cryosphere Sciences,Cold and Arid Regions Environmental and Engineering Research Insti-tute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 3.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 4.Department of Meteorology,The Pennsylvania State University,University Park,PA 16802 5.State Key Laboratory of Earth Surface Processes and Ecology Resource,Beijing Normal University,Beijing 100875,China 2008Research in Cold and Arid Regions2008,,1:44
3Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China显示文摘To control the spread of the 2019 novel coronavirus(COVID-19),China imposed nationwide restrictions on the movement of its population(lockdown)after the Chinese New Year of 2020,leading to large reductions in economic activities and associated emissions.Despite such large decreases in primary pollution,there were nonetheless several periods of heavy haze pollution in eastern China,raising questions about the well-established relationship between human activities and air quality.Here,using comprehensive measurements and modeling,we show that the haze during the COVID lockdown was driven by enhancements of secondary pollution.In particular,large decreases in NOx emissions from transportation increased ozone and nighttime NO_(3)radical formation,and these increases in atmospheric oxidizing capacity in turn facilitated the formation of secondary particulate matter.Our results,afforded by the tragic natural experiment of the COVID-19 pandemic,indicate that haze mitigation depends upon a coordinated and balanced strategy for controlling multiple pollutants.Xin Huang Aijun Ding Jian Gao Bo Zheng Derong Zhou Ximeng Qi Rong Tang Jiaping Wang Chuanhua Ren Wei Nie Xuguang Chi Zheng Xu Liangduo Chen Yuanyuan Li Fei Che Nini Pang Haikun Wang Dan Tong Wei Qin Wei Cheng Weijing Liu Qingyan Fu Baoxian Liu Fahe Chai Steven JDavis Qiang Zhang Kebin He 2021National Science Review2021,8,2:47
4Aerosol and boundary-layer interactions and impact on air quality显示文摘Air quality is concerned with pollutants in both the gas phase and solid or liquid phases. The latter are referred to as aerosols, which are multifaceted agents affecting air quality, weather and climate through many mechanisms. Unlike gas pollutants, aerosols interact strongly with meteorological variables with the strongest interactions taking place in the planetary boundary layer(PBL). The PBL hosting the bulk of aerosols in the lower atmosphere is affected by aerosol radiative effects. Both aerosol scattering and absorption reduce the amount of solar radiation reaching the ground and thus reduce the sensible heat fluxes that drive the diurnal evolution of the PBL. Moreover, aerosols can increase atmospheric stability by inducing a temperature inversion as a result of both scattering and absorption of solar radiation, which suppresses dispersion of pollutants and leads to further increases in aerosol concentration in the lower PBL.Such positive feedback is especially strong during severe pollution events. Knowledge of the PBL is thus crucial for understanding the interactions between air pollution and meteorology. A key question is how the diurnal evolution of the PBL interacts with aerosols, especially in vertical directions, and affects air quality.We review the major advances in aerosol measurements, PBL processes and their interactions with each other through complex feedback mechanisms, and highlight the priorities for future studies.Zhanqing Li Jianping Guo Aijun Ding Hong Liao Jianjun Liu Yele Sun Tijian Wang Huiwen Xue Hongsheng Zhang Bin Zhu 2017National Science Review2017,4,6:37
5Roles of Chemokine Receptor 4 (CXCR4) and Chemokine Ligand 12 (CXCL12) in Metastasis of Hepatocellular Carcinoma Cells显示文摘Chemokines are involved in human hepatocellular carcinoma (HCC) carcinogenesis. However, the exact mechanism of chemokines in HCC carcinogenesis remains unknown. Here we investigated the roles of chemokine receptor 4 (CXCR4) and chemokine ligand 12 (CXCL12) in the metastasis of HCC. We found that the expression levels of CXCR4 mRNA in HCC tissues, MHCC97 cells, and HUVEC cells were 2.52 ± 1.13, 2.34 ± 1.16 and 1.63 ± 1.26, respectively and that the CXCR4 protein levels were 1.38 ± 0.13, 1.96 ± 0.32 and 1.86 ± 0.21, respectively. In contrast, CXCR4 was not detected in normal hepatic tissues. In 78 HCC patients, we also found that the concentration of CXCL12 in cancerous ascitic fluid was 783-8,364 pg/ml and that CXCL12 mRNA level in HCC metastasis portal lymph nodes was 1.21 ± 0.87 but undetectable in normal hepatic tissues. Finally we discovered that recombinant human CXCL12 could induce MHCC97 cells and HUVEC cells to migrate with chemotactic indexes (CI) of 3.9 ± 1.1 and 4.1 ± 1.6, respectively. Cancerous ascitic fluid could also induce the migration of MHCC97 cells with a CI of 1.9 ± 0.8. Thus, our data suggest that CXCR4 and CXCL12 may play an important role in the metastasis of HCC by promoting the migration of tumor cells.Hui Liu Zeya Pan Aijun Li Siyuan Fu Yin Lei Hangyong Sun Mengchao Wu Weiping Zhou 2008Cellular & Molecular Immunology2008,5,5:30
6Effect of Ce doping of TiO_2 support on NH_3-SCR activity over V_2O_5–WO_3/CeO_2–TiO_2 catalyst显示文摘CeO2–TiO2composite supports with different Ce/Ti molar ratios were prepared by a homogeneous precipitation method, and V2O5–WO3/CeO2–TiO2catalysts for the selective catalytic reduction(SCR) of NOx with NH3 were prepared by an incipient-wetness impregnation method. These catalysts were characterized by means of BET, XRD, UV–Vis,Raman and XPS techniques. The results showed that the catalytic activity of V2O5–WO3/TiO2 was greatly enhanced by Ce doping(molar ratio of Ce/Ti = 1/10) in the TiO2 support.The catalysts that were predominantly anatase TiO2 showed better catalytic performance than the catalysts that were predominantly fluorite CeO2. The Ce additive could enhance the surface adsorbed oxygen and accelerate the SCR reaction. The effects of O2 concentration, ratio of NH3/NO, space velocity and SO2 on the catalytic activity were also investigated. The presence of oxygen played an important role in NO reduction. The optimal ratio of NH3/NO was 1/1 and the catalyst had good resistance to SO2 poisoning.Kai Cheng Jian Liu Tao Zhang Jianmei Li Zhen Zhao Yuechang Wei Guiyuan Jiang Aijun Duan 2014Journal of Environmental Sciences2014,26,10:18
7Sodium humate accelerates cutaneous wound healing by activating TGF-β/Smads signaling pathway in rats显示文摘Sodium humate(HA-Na) has been topically used as a wound healing and anti-inflammatory agent in folk medicine. In the present study, HA-Na was investigated for cutaneous wound healing in Sprague–Dawley rats. HA-Na solution(1.0%, w/v) was topically administered to rats undergoing excision wound models. Healing was assessed with a recombinant bovine basic fibroblast growth factor for external use as positive control. Wound healing rates were calculated on Day 3, 6, 9, 14 and 21 after injury, and tissues were also harvested after the same intervals for histological analysis. In addition, tissue hydroxyproline levels were measured. Furthermore, m RNA levels and protein expressions of transforming growth factor-β1, 2, 3(TGF-β1, 2, 3) were determined by RT-PCR and western blot. Protein expression levels of Smad-2,-3,-4 and-7 were also detected by western blot. Our study demonstrates that HA-Na has the capacity to promote wound healing in rats via accelerated wound contraction and increased hydroxyproline content. More importantly, these wound healing effects of HA-Na might be mediated through the TGF-β/Smad signaling pathway. HA-Na may be an effective agent for enhanced wound healing.Yuanyuan Ji Aijun Zhang Xiaobin Chen Xiaoxia Che Kai Zhou Zhidong Wang 2016Acta Pharmaceutica Sinica B2016,6,2:17
8NH_3-SCR denitration catalyst performance over vanadium–titanium with the addition of Ce and Sb显示文摘Selective catalytic reduction technology using NH3 as a reducing agent(NH3-SCR) is an effective control method to remove nitrogen oxides. TiO2-supported vanadium oxide catalysts with different levels of Ce and Sb modification were prepared by an impregnation method and were characterized by X-ray diffractometer(XRD), Brunauer–Emmett–Teller(BET), Transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FT-IR), UV–Vis diffuse reflectance spectroscopy(UV–Vis DRS), Raman and Hydrogen temperature-programmed reduction(H2-TPR). The catalytic activities of V5 CexS by/TiO2 catalysts for denitration were investigated in a fixed bed flow microreactor. The results showed that cerium, vanadium and antimony oxide as the active components were well dispersed on TiO2, and the catalysts exhibited a large number of d–d electronic transitions, which were helpful to strengthen SCR reactivity. The V5 CexS by/TiO2 catalysts exhibited a good low temperature NH3-SCR catalytic activity. In the temperature range of 210 to 400℃, the V5 CexS by/TiO2 catalysts gave NO conversion rates above 90%. For the best V5Ce35Sb2/TiO2 catalyst, at a reaction temperature of 210℃, the NO conversion rate had already reached 90%. The catalysts had different catalytic activity with different Ce loadings. With the increase of Ce loading, the NO conversion rate also increased.Chi Xu Jian Liu Zhen Zhao Fei Yu Kai Cheng Yuechang Wei Aijun Duan Guiyuan Jiang 2015Journal of Environmental Sciences2015,27,5:17
9Precision orchard sprayer based on automatically infrared target detecting and electrostatic spraying techniques显示文摘There is an urgent need for new chemical application techniques and sprayers in Chinese orchard spraying.A new tractor-mounted automatic target detecting electrostatics,and air-assisted orchard sprayer was designed and developed to meet the demand of chemical pest control in orchards.This sprayer light weighted,highly efficient,reduces pesticide use and is friendly to the environment.The techniques of automatic target detecting,electrostatics,and air-assisted spraying were combined in this system.The electrostatically charged droplets are projected toward the target by the assistance of an air stream that increases the droplets penetration within canopy.Experimental results show that the new automatic target detecting orchard sprayer with an infrared sensor can save more than 50%to 75%of pesticides,improve the utilization rate(over 55%),control efficiency,and significantly reduce environmental pollution caused by the pesticide application.At the same time the key technological problems related to air-assisted low volume and electrostatic spraying were solved.He Xiongkui Zeng Aijun Liu Yajia Song Jianli 2011International Journal of Agricultural and Biological Engineering2011,4,1:17
10MiR-30a Positively Regulates the Inflammatory Response of Microglia in Experimental Autoimmune Encephalomyelitis显示文摘Multiple sclerosis(MS) is a classical inflammatory demyelinating disease of the central nervous system(CNS). Microglia are the main resident immune cells in the CNS and are closely associated with the pathogenesis of MS.In the present study, we found that mi R-30 a was highly expressed in jellyfish-like microglia in chronic active lesions of MS patients, as well as in the microglia of mice with experimental autoimmune encephalomyelitis(EAE) at the chronic phase. In vitro, the conditioned supernatant of mouse microglia overexpressing miR-30 a promoted the apoptosis of oligodendrocyte precursor cells(OPCs), and inhibited OPC differentiation. In vivo, overexpressing miR-30 a in transplanted microglia exacerbated the progression of EAE.Overexpression and knock-down experiments in primary cultured mouse microglia showed that mi R-30 a increased the expression of IL-1 b and i NOS, which are pro-inflammatory, while inhibiting the expression of Ym-1 and CD206.Mechanistically, mi R-30 a inhibited the expression of Ppargc1 b, which is the co-activator of peroxisome proliferator-activated receptor gamma, resulting in pro-inflammatory effects. Our work shows that mi R-30 a is an important regulator of the inflammatory response in microglia, and may be a promising therapeutic target for inflammatory diseases like MS in the CNS.Xue Fang Dingya Sun Zhihong Wang Zhongwang Yu Weili Liu Yingyan Pu Dan Wang Aijun Huang Mingdong Liu Zhenghua Xiang Cheng He Li Cao 2017Neuroscience Bulletin2017,33,6:16
11Climatic trends of different intensity heavy precipitation events concentration in China显示文摘Based on 740 stations of daily precipitation datasets in China, the precipitation- concentration degree (PCD)and precipitation-concentration period (PCP)ofdifferentintensity durative precipitation eventswere calculated to analyze theirstatisticalcharacteristics,mainly including spatial and temporaldistributions,variations and climatic trends ofthe two parameters ofthe durative heavy precipitation events in China.Itis proved thatthese two parameters ofheavy rainfallcan display the temporalinhomogeneity in the precipitation field.And itis also found thatthere is a good positive relationship between the precipitation-concentration degree and annualrainfallamountin the Eastern and CentralChina.Thismethod can beapplied in flood assessmentand climatechangefields.XIE Zhiqing DU Yin JIANG Aijun DING Yuguo 2005Journal of Geographical Sciences2005,15,4:15
12A BAC clone of MDV strain GX0101 with REV-LTR integration retained its pathogenicity显示文摘The complete genome of Marek's disease virus (MDV) strain GX0101, which was integrated with the LTR sequences of REV, was cloned in Escherichia coli as a bacterial artificial chromosome (BAC). BAC vector sequences were introduced into the US2 locus of the MDV genome by homologous recombination. The viral DNA containing the BAC vector was used to transform Escherichia coli strain of DH10B. Then the recombinant virus was successfully rescued by transfection of the recombinant BAC DNA into primary chicken embryo fibroblast (CEF). This BAC viral clone was named bac-GX0101. When the reconstituted virus was inoculated into 1-day-old birds, visceral tumors could be detected as early as 62 d post infection. There was no difference in growth ability and pathogenicity to birds between the BAC derived virus and its parental virus. The BAC derived virus maintained its oncogenicity and immunosuppressive effects. In conclusion, the complete genome of GX0101 strain was successfully cloned into BAC and the infectious clone was rescued. With the powerful BAC manipulation system, the infectious clone will provide a useful tool for further understanding the functional roles of the inserted REV-LTR sequence in the GX0101 strain of MDV.SUN AiJun LAWRENCE Petherbridge ZHAO YuGuang LI YanPeng NAIR Venugopal K CUI ZhiZhong 2009Chinese Science Bulletin2009,54,15:15
13Impact of the cord-grass Spartina alterniflora on sedimentary and morphological evolution of tidal salt marshes on the Jiangsu coast,China显示文摘The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is highly complicated. The cord-grass Spartina alterniflora, which was introduced artificially into the Jiangsu coast, has significant influences on the regional tidal flat evolution in terms of deposition rate, spacial sediment distribution patterns and tidal creek morphology. On the basis of the data set of bed elevation and accumulation rate for different periods of time, the applicability of the Pethick-Allen model to the Jiangsu tidal salt marshes is discussed. In addition, caesium-137 dating was carried out for sediment samples collected from the salt marsh of the Wangang area. In combination with the caesium-137 analysis and the data collected from literature, the Pethick-Allen model was used to derive the accumulation rate in the Wanggang tidal flat for the various periods. The results show that the pattern of tidal flat accretion has been modified, due to more rapid accretion following the introduction of S.alterniflora to the region. Surficial sediment samples were collected from representative profiles and analyzed for grain size with a laser particle analyzer. The result shows that fine-grained sediment has been trapped by the plant, with most of the sediment deposited on the Suaeda salsa and Spartina angelica flats being derived from drainage creeks rather than the from gently sloping tidal flats. Remote sensing analysis and in situ observations indicate that the creeks formed in the S.alterniflora flat have a relatively small ratio of width to depth, a relatively high density, and are more stable than the other tidal flat creek systems in the study area.WANG Aijun GAO Shu JIA Jianjun 2006Acta Oceanologica Sinica2006,25,4:15
14FY-3E:The First Operational Meteorological Satellite Mission in an Early Morning Orbit显示文摘Fengyun-3 E(FY-3E),the world’s first early-morning-orbit meteorological satellite for civil use,was launched successfully at the Jiuquan Satellite Launch Center on 5 July 2021.The FY-3E satellite will fill the vacancy of the global early-morning-orbit satellite observation,working together with the FY-3C and FY-3D satellites to achieve the data coverage of early morning,morning,and afternoon orbits.The combination of these three satellites will provide global data coverage for numerical weather prediction(NWP)at 6-hour intervals,effectively improving the accuracy and time efficiency of global NWP,which is of great significance to perfect the global earth observing system.In this article,the background and meteorological requirements for the early-morning-orbit satellite are reviewed,and the specifications of the FY-3E satellite,as well as the characteristics of the onboard instrumentation for earth observations,are also introduced.In addition,the ground segment and the retrieved geophysical products are also presented.It is believed that the NWP communities will significantly benefit from an optimal temporal distribution of observations provided by the early morning,mid-morning,and afternoon satellite missions.Further benefits are expected in numerous applications such as the monitoring of severe weather/climate events,the development of improved sampling designs of the diurnal cycle for accurate climate data records,more efficient monitoring of air quality by thermal infrared remote sensing,and the quasicontinuous monitoring of the sun for space weather and climate.Peng ZHANG Xiuqing HU Qifeng LU Aijun ZHU Manyun LIN Ling SUN Lin CHEN Na XU 2022Advances in Atmospheric Sciences2022,39,1:13
15Sediment dynamic responses of coastal salt marsh to typhoon “KAEMI” in Quanzhou Bay,Fujian Province,China显示文摘In order to understand the mechanisms of coastal protection by salt marshes during typhoon events,in situ measurements of water level,tidal current speed and direction,and suspended sediment concen-tration (SSC) were carried out using Electromagnetic Current Meter (EMCM,AEM HR),miniature pres-sure sensor (MkV/D) and Seapoint Turbidity Meter (STM) sensor on a tidal flat in Quanzhou Bay,during the period when the typhoon 'KAEMI' was passing through the region. The analysis of the data ob-tained shows that the near-bed current speed within the Spartina alterniflora marsh was generally be-low 5 cm s-1,which was apparently smaller than on the adjacent bare flat (i.e. 5―30 cm s-1). The change in the near-bed current speed in response to the typhoon event was not significant within the S. al-terniflora marsh,but the current direction was influenced by the typhoon. The effect of the typhoon on the SSC was highly significant,with the SSC reaching 13 to 19 times the values on the bare flat or within the marsh under fair weather conditions; the near-bed SSC within the marsh was higher than on the bare flat,after the typhoon landed. The near-bed suspended sediment fluxes within the marsh and on the bare flat during the typhoon event were both enhanced,i.e.,4 times larger than under fair weather conditions. During the ebb,the bottom shear stress on the bare flat exceeded the critical shear stress for sediment motion for most of the ebb duration of the tide and,therefore,the bed sediment was eroding,with the erosion flux after the typhoon landed being around 2 to 3 times the value associated with fair weather conditions. In contrast,within the S. alterniflora marsh,the bottom shear stress was mostly lower than the critical shear stress for sediment motion,or lower than the critical shear stress for the maintenance of suspension; hence,the marsh surface was dominated by settling processes,with a settling flux during the typhoon being 3 to 6 times compared with the fair weather situations. The settling flux during the ebb was up to twice the magnitude for the flood. The comparison of sediment dynamic processes between the S. alterniflora marsh and the bare flat demonstrates that during the typhoon event the bare flat was dominated by erosion,whilst the presence of S. alterniflora favored the accretion of suspended sediment.WANG AiJun GAO Shu CHEN Jian LI DongYi 2009Chinese Science Bulletin2009,54,1:12
16Improved CICA Algorithm Used for Single Channel Compound Fault Diagnosis of Rolling Bearings显示文摘A Compound fault signal usually contains multiple characteristic signals and strong confusion noise, which makes it difficult to separate week fault signals from them through conventional ways, such as FFT-based envelope detection, wavelet transform or empirical mode decomposition individually. In order to realize single channel compound fault diagnosis of bearings and improve the diagnosis accuracy, an improved CICA algorithm named constrained independent component analysis based on the energy method(E-CICA) is proposed. With the approach, the single channel vibration signal is firstly decomposed into several wavelet coefficients by discrete wavelet transform(DWT) method for the purpose of obtaining multichannel signals. Then the envelope signals of the reconstructed wavelet coefficients are selected as the input of E-CICA algorithm, which fulfills the requirements that the number of sensors is greater than or equal to that of the source signals and makes it more suitable to be processed by CICA strategy. The frequency energy ratio(ER) of each wavelet reconstructed signal to the total energy of the given synchronous signal is calculated, and then the synchronous signal with maximum ER value is set as the reference signal accordingly. By this way, the reference signal contains a priori knowledge of fault source signal and the influence on fault signal extraction accuracy which is caused by the initial phase angle and the duty ratio of the reference signal in the traditional CICA algorithm is avoided. Experimental results show that E-CICA algorithm can effectively separate out the outer-race defect and the rollers defect from the single channel compound fault and fulfill the needs of compound fault diagnosis of rolling bearings, and the running time is 0.12% of that of the traditional CICA algorithm and the extraction accuracy is 1.4 times of that of CICA as well. The proposed research provides a new method to separate single channel compound fault signals.CHEN Guohua QIE Longfei ZHANG Aijun HAN Jin 2016Chinese Journal of Mechanical Engineering2016,29,1:12
17A novel four-way combining catalysts for simultaneous removal of exhaust pollutants from diesel engine显示文摘A novel four-way combining catalysts containing double layers was applied to simultaneously remove four kinds of exhaust pollutants(NOx,CO,HC and PM) emitted from diesel engine.The four-way catalysts were characterized using scanning electron microscope(SEM) and Ultraviolet visible diffuse reflectance spectroscopy(UV-Vis DRS).Their catalytic performances were evaluated by temperature-programmed reaction technology.The double layer catalysts could effectively remove the four main pollutants.The highest catalytic activity was given by the two-layered catalysts of La0.6K0.4CoO3/Al2O3 and W/HZSM-5.Under the simulated exhaust gases conditions,the peak temperature of the soot combustion was 421°C,the maximal conversion of NO to N2 was 74%,the temperature of the HC total conversion was 357°C,and the maximum conversion ratio of CO was 99%.Jian Liu,Jie Xu,Zhen Zhao,Aijun Duan,Guiyuan Jiang,Yanni Jing State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249,China. 2010Journal of Environmental Sciences2010,22,7:11
18Scheduling optimization of task allocation in integrated manufacturing system based on task decomposition显示文摘How to deal with the collaboration between task decomposition and task scheduling is the key problem of the integrated manufacturing system for complex products. With the development of manufacturing technology, we can probe a new way to solve this problem. Firstly, a new method for task granularity quantitative analysis is put forward, which can precisely evaluate the task granularity of complex product cooperation workflow in the integrated manufacturing system, on the above basis; this method is used to guide the coarse-grained task decomposition and recombine the subtasks with low cohesion coefficient. Then, a multi-objective optimieation model and an algorithm are set up for the scheduling optimization of task scheduling. Finally, the application feasibility of the model and algorithm is ultimately validated through an application case study.Aijun Liu Michele Pfund John Fowler 2016Journal of Systems Engineering and Electronics2016,27,2:10
19Tuning oxygen vacancies in two-dimensional iron-cobalt oxide nanosheets through hydrogenation for enhanced oxygen evolution activity显示文摘Linzhou Zhuang Yi Jia Tianwei He Aijun Du Xuecheng Yan Lei Ge Zhonghua Zhu Xiangdong Yao 2018Nano Research2018,11,6:10
20miR-210 over-expression enhances mesenchymal stem cell survival in an oxidative stress environment through antioxidation and c-Met pathway activation显示文摘microRNA-210(miR-210)has generally been reported to be associated with cell survival under hypoxia.However,there are few data regarding the role of miR-210 in the survival of mesenchymal stem cells(MSCs)under oxidative stress conditions.Thus,we sought to investigate whether miR-210 over-expression could protect MSCs against oxidative stress injury and what the primary mechanisms involved are.The results showed that over-expression of miR-210 significantly reduced the apoptosis of MSCs under oxidative stress,accompanied by obvious increases in cell viability and superoxide dismutase activity and remarkable decreases in malonaldehyde content and reactive oxygen species production,resulting in a noticeable reduction of apoptotic indices when compared with the control.Moreover,the above beneficial effects of miR-210 could be significantly reduced by c-Met pathway repression.Collectively,these results showed that miR-210 over-expression improved MSC survival under oxidative stress through antioxidation and c-Met pathway activation,indicating the potential development of a novel approach to enhance the efficacy of MSC-based therapy for injured myocardium.XU JianFeng HUANG ZheYong LIN Li FU MingQiang GAO YanHua SHEN YunLi ZOU YunZeng SUN AiJun QIAN JuYing GE JunBo 2014Science China(Life Sciences)2014,57,10:10
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