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Length Scale of Photospheric Granules in Solar Active Regions

Research in Astronomy and Astrophysics 2022年第8期22卷 103-110页

作者： Yan-Xiao Liu Chao-Wei Jiang Ding Yuan Ping-Bing Zuo Wen-da cao institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen 518055China New Jersey institute of Technology Center for Solar ResearchNewarkNJUSA Big Bear Solar Observatory 40386 North Shore LaneBig Bear CityCAUSA

investigating the length scales of granules could help understand the dynamics of granules in the *** this work,we detected and identified granules in an active region near disk center observed at wavelength of TiO(7057?)by the 1.6 m Goode Solar Telescope(GST).By a detailed analysis of the size distribution and flatness of granules,we found a critical size that divides the granules in motions into two regimes:convection and *** length scales of granules with sizes larger than 600 km follow Gauss function and demonstrate“flat”in flatness,which reveal that these granules are dominated by *** with sizes smaller than 600 km follow power-law function and behave power-law tendency in flatness,which indicate that the small granules are dominated by ***,for the granules in active regions,they are originally convective in large length scale,and directly become turbulent once their sizes turn to small,likely below the critical size of 600 *** with the granules in quiet regions,they evolve with the absence of the mixing motions of convection and *** a difference is probably caused by the interaction between fluid motions and strong magnetic fields in active *** strong magnetic fields make high magnetic pressure which creates pressure walls and slows down the evolution of convective *** walls cause convective granules extending to smaller sizes on one hand,and cause wide intergranular lanes on the other *** small granules isolated in such wide intergranular lanes are continually sheared,rotated by strong downflows in surroundings and hereby become turbulent.

关键词： Sun:granulation Sun:photosphere Sun:faculae plages

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Effects of Barium Stress in Brassica juncea and ca.ile maritima:The indicator Role of Some Antioxidant Enzymes and Secondary Metabolites

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Phyton-international Journal of Experimental Botany 2021年第1期90卷 145-158页

作者： Houda Bouslimi Renata Ferreira Nesrine Dridi Pedro Brito Susete Martins-Dias isabel caçador Noomene Sleimi Laboratory of Resources Materials and EcosystemsFaculty of Sciences of BizerteUniversity of CarthageJarzounaBizerte7021Tunisia Centro de Recursos Naturais e Ambiente Instituto Superior TécnicoUniversidade de LisboaLisbon1049-001Portugal instituto Português do Mare da Atmosfera Rua Dr.Alfredo Magalhães RamalhoLisbon1495-006Portugal Centro de Recursos Naturais e Ambiente DBEInstituto Superior TécnicoUniversidade de LisboaLisbon1049-001Portugal Marine and Environmental Sciences Centre Faculdade de CiênciasUniversidade de LisboaCampo GrandeLisbon1749-016Portugal

Soil contamination by toxic trace metal elements,like barium(Ba),may stimulate various undesirable changes in the metabolic activity of *** plant responses are fast and with,direct or indirect,generation of reactive oxygen species(ROS).To cope with the stress imposed by the ROS production,plants developed a dual cellular system composed of enzymatic and non-enzymatic players that convert ROS,and their by-products,into stable nontoxic *** assess the Ba stress response of two Brassicaceae species(Brassica juncea,a glycophyte,and ca.ile maritime,a halophyte),plants were exposure to different Ba concentrations(0,100,200,300 and 500µM).The plants response was evaluated through their morphology and development,the determination of plant leaves antioxidant enzymatic activities and by the production of plants secondary *** indicated that the two Brassicaceae species have the ability to survive in an environment containing Ba(even at 500µM).The biomass production of *** was slightly affected whereas an increase in biomass *** was *** stress imposed by Ba activated the antioxidant defense system in the two species,noticed by the changes in the leaves activity of catalase(caT),ascorbate peroxidase(APX)and guaicol peroxidase(GPX),and of the secondary metabolites,through the production of total phenols and *** enzymatic response was not similar within the two plant species:caT and APX seem to have a more important role against the oxidative stress in *** while in *** is ***,total phenols and flavonoids production was more significant in the plants aerial part than in the roots,of the both *** the two Brassicaceae species response was different,in both plants catalytic and non-catalytic transformation of ROS occurs,and both were able to overcome the Ba toxicity and prevent the cell damage.

关键词： Brassica juncea ca.ile maritima antioxidant enzymes barium stress oxidative stress secondary metabolites

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Conversion of Au(Ⅲ)-polluted waste eggshell into functional caO/Au nanocatalyst for biodiesel production

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Green Energy & Environment 2022年第2期7卷 352-359页

作者： Jiadi Liu Minghuan Liu Shaoyun Chen Bingqing Wang Jin Chen da-Peng Yang Shangzhou Zhang Wenxiao Du College of Life Science Yantai UniversityYantaiShandong Province264005China School of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantaiShandong Province264005China College of Chemical Engineering and Materials Science Quanzhou Normal UniversityQuanzhouFujian Province362000China Clinical Center for Molecular Diagnosis and Therapy The Second Affiliated Hospital of Fujian Medical UniversityQuanzhouShandong Province362000China

Developing an environmental-friendly and highly active catalyst in transesterifica.ion for biodiesel production is of great importance for a more economic biodisel ***,we reported that waste eggshells were used to adsorb Au(Ⅲ) in water and convert the Au(Ⅲ)-polluted eggshells into the functional nanocatalyst-ca O/Au for the transesterifica.ion reaction between soybean oil and methanol to the preparation of *** coupling of ca O and Au nanoparticles,ca O/Au nanoparticles showed superior catalytic activity for the transesterifica.ion reaction between soybean oil and *** optimum performance was observed over ca O/Au nanocomposites in a methanol-oil molar ratio at 12:1with catalyst content of 1.0 wt% at 70°C for 3 ***,the catalytic activity of ca O/Au nanocatalyst was almost unchanged after recycling for 5 times and the yield of biodiesel still kept at 88.9%.The proof-of concept study provided us a sustainable method for utilization of waste eggshells to remedy the metal ions-polluted wastewater and the synthesis of functional nanocomposite for biodiesel production,show great potential applica.ion of waste eggshell in adsorption and catalytic reactions.

关键词： process Au(Ⅲ) catalyst

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Diagnostics of Ellerman bombs with high-resolution spectral data

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Research in Astronomy and Astrophysics 2015年第9期15卷 1513-1524页

作者： Zhen Li Cheng Fang Yang Guo Peng-Fei Chen Zhi Xu Wen-da cao School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education Collaborative innovation Center of Modern Astronomy and Space Exploration Yunnan Observatories Chinese Academy of Sciences Big Bear Solar Observatory New Jersey Institute of Technology

Ellerman bombs （EBs） are tiny brightenings often observed near sunspots. The most impressive characteristic of EB spectra is the two emission bumps in both wings of the Hα and ca.ii 8542 A lines. High-resolution spectral data of three small EBs were obtained on 2013 June 6 with the largest solar telescope, the 1.6 m New Solar Telescope at the Big Bear Solar Observatory. The characteristics of these EBs are analyzed. The sizes of the EBs are in the range of 0.3＂ - 0.8＂ and their durations are only 3-5 min. Our semi-empirical atmospheric models indicate that the heating occurs around the temperature minimum region with a temperature increase of 2700- 3000 K, which is surprisingly higher than previously thought. The radiative and kinetic energies are estimated to be as high as 5 × 1025 - 3.0 × 10^26 erg despite the small size of these EBs. Observations of the magnetic field show that the EBs just appeared in a parasitic region with mixed polarities and were accompanied by mass motions. Nonlinear force-free field extrapolation reveals that the three EBs are connected with a series of magnetic field lines associated with bald patches, which strongly implies that these EBs should be produced by magnetic reconnection in the solar lower atmosphere. According to the lightcurves and the estimated magnetic reconnection rate, we propose that there is a three phase process in EBs： pre-heating, flaring and cooling phases.

关键词： Sun: chromosphere -- Sun: photosphere -- line profiles -- magnetic reconnection

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Soil Acidifica.ion and Heavy Metals in Urban Parks as Affected by Reconstruction intensity in a Humid Subtropical Environment

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Pedosphere 2015年第1期25卷 82-92页

作者： HOU En-Qing XiANG Hui-Min Li Jian-Li Li Jiong WEN da-Zhi institute of Ecology and Environmental Sciences South China Botanical Garden Chinese Academy of Sciences Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical Garden Chinese Academy of Sciences University of Chinese Academy of Sciences Agricultural and Forestry Extension Centre of Nanhai District

Soil quality is a major concern in the management of urban parks. in this study, the soils at 0–3, 3–13, and 13–23 cm depths were sampled from six urban parks, differing in reconstruction intensity(mainly changes made during conversion of natural forests into parklands), in the Pearl River Delta, China to determine how reconstruction intensity influenced the extent of acidifica.ion and heavy metal levels in the soils of urban parks in a humid subtropical environment. High reconstruction intensity(HRi) was practiced in three parks and low reconstruction intensity(LRi) in three other parks. The LRi soils were strongly to extremely acidic(with low exchangeable ca, Mg, and K concentrations) while the HRi soils were much less acidic. Both total and extractable concentrations of soil heavy metals were related to the specific management practices and age of the park, but did not differ significantly between LRi and HRi parks or among soil depths. Soil p H was significantly related to soil exchangeable ca.ion concentrations and base saturation but was weakly related or unrelated to soil heavy metal levels. Our results suggest that high intensity but not low intensity reconstruction significantly reduces the extent of soil acidifica.ion in the urban parks in a humid subtropical environment.

关键词： exchangeable ca.ions forest park age park management soil depth soil p H soil quality

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Simulation and experiment of the cooling effect of trapped ion by pulsed laser

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Chinese Physics B 2021年第7期30卷 226-233页

作者： Chang-da-Ren Fang Yao Huang Hua Guan Yuan Qian Ke-Lin Gao State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China Key Laboratory of Atomic Frequency Standards Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

We investigate the process of pulsed laser cooling using a self-constructed molecular dynamics simulation(MDSimulation)*** simulate the Doppler cooling process and pulsed laser Doppler cooling process of a single^(40)ca^(+)ion,and the comparison with the experimental results shows that this self-constructed MD-Simulation program works well in the weak laser intensity ***,we analyze the pulsed laser Doppler cooling process of a single^(27)Al^(+)*** program can be used to analyze the molecular dynamic process of various situations of Doppler cooling in an ion trap,which could give predictions and experimental guidance.

关键词： doppler cooling pulsed laser cooling molecular dynamics simulation

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Bioturbation of Thalassinoides from the Lower cambrian Zhushadong Formation of Dengfeng area, Henan Province, North China

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Journal of Palaeogeography 2021年第1期10卷 39-54页

作者： Yu-Chao Fan Yong-An Qi Ming-Yue dai da Li Bing-Chen Liu Guo-Shuai Qing School of Resources and Environment Henan Polytechnic UniversityJiaozuo 454000Henan ProvinceChina

Bioturbation plays a critical role in sediment mixing and biogeochemical cycling between sediment and *** abundance of bioturbation structures, dominated by Thalassinoides, occurs in carbonate rocks of the cambrian Series 2 Zhushadong Formation in the Dengfeng area of western Henan Province, North China. Determination of elemental geochemistry can help to establish the influence of burrowing activities on sediment biogeochemical cycling, especially on changes in oxygen concentration and nutrient regeneration. Results show that there is a dramatic difference in the bioturbation intensity between the bioturbated limestone and laminated dolostone of the Zhushadong Formation in terms of productivity proxies(Baex, Cu, Ni, Sr/ca) and redox proxies(V/Cr, V/Sc, Ni/Co). These changes may be related to the presence of Thalassinoides bioturbators, which alter the particle size and permeability of sediments, while also increase the oxygen concentration and capacity for nutrient *** with modern studies shows that the sediment mixing and reworking induced by Thalassinoides bioturbators significantly changed the primary physical and chemical characteristics of the cambrian sediment,triggering the substrate revolution and promoting biogeochemical cycling between sediment and seawater.

关键词： Thalassinoides Sediment mixing Oxygen concentration Nutrient regeneration Trace element proxy Early cambrian North China Platform

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A clinical evaluation of serological diagnosis for pancreatic cancer

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World Journal of Gastroenterology 1998年第2期4卷 55-57页

作者： Zhao, XY Yu, SY da, SP Bai, L Guo, XZ dai, XJ Wang, YM Third Mil Med Univ Xinqiao Hosp Dept Gastroenterol Chongqing 400037 Peoples R China

ＡｃｌｉｎｉｃａｌｅｖａｌｕａｔｉｏｎｏｆｓｅｒｏｌｏｇｉｃａｌｄｉａｇｎｏｓｉｓｆｏｒｐａｎｃｒｅａｔｉｃｃａｎｃｅｒＺＨＡＯＸｉａｏＹａｎ，ＹＵＳｈｉＹｕａｎ，ＤＡＳｈｉＰｉｎｇ，ＢＡＩＬｉ，ＧＵＯＸｉａ... 详细信息

ＡｃｌｉｎｉｃａｌｅｖａｌｕａｔｉｏｎｏｆｓｅｒｏｌｏｇｉｃａｌｄｉａｇｎｏｓｉｓｆｏｒｐａｎｃｒｅａｔｉｃｃａｎｃｅｒＺＨＡＯＸｉａｏＹａｎ，ＹＵＳｈｉＹｕａｎ，ＤＡＳｈｉＰｉｎｇ，ＢＡＩＬｉ，ＧＵＯＸｉａｏＺｈｏｎｇ，ＤＡＩＸｉａｏＪ...

关键词： pancreatic neoplasms/diagnosis tumor markers, biological antigens, neoplasm/analysis ca 19 9 antigen/analysis pancreatopeptidase/analysis carcinoembryonic antigen/analysis alpha 1 antitrypsin/analysis enzyme linked immunosorbent assay radioim

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Pilaring of Zn_2Al Layered Double Hydroxide by dawson Polyoxometalate Anions

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Chemical Research in Chinese Universities 1998年第2期14卷 68-70页

作者： GUO Jun Li Yun-lun JiAO Qing-ze JiANG da-zhen MiN En-ze Department of Chemistry Jilin UniversityChangchun130023 Research institute of Petroleum Processing Beijing100083

Zn2Al layered double hydroxide pillared with dawson polyoxometalates,P2W17ZO8-61(Z=Mn2+,Co2+,Ni2+,Cu2+,Zn2+)was prepared.A basal space ofca.16 nm indicates the intercalated dawson ions to be oriented with their C2 axis perpendicular to the double hydroxide layers(with the exception of P2W17ZnLDH).The iR and^(13)P MASNMR spectral reveal that the dawson ions retain their integrity in the interlayer space of LDH.A preliminary study shows that these compounds are highly active catalysts for the oxidation of cyclohexene with molecular oxygen.

关键词： Pillaring dawson structure Polyoxometalate anions

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The statistical power of k-mer based aggregative statistics for alignment-free detection of horizontal gene transfer

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Synthetic and Systems Biotechnology 2019年第3期4卷 150-156页

作者： Guan-da Huang Xue-Mei Liu Tian-Lai Huang Li-C.Xia School of Physics and Optoelectronics South China University of TechnologyGuangzhou510640China Department of Medicine Stanford University School of MedicineStanfordCA94305USA

Alignment-based database search and sequence comparison are commonly used to detect horizontal gene transfer(HGT).However,with the rapid increase of sequencing depth,hundreds of thousands of contigs are routinely assembled from metagenomics studies,which challenges alignment-based HGT analysis by overwhelming the known reference *** HGT by k-mer statistics thus becomes an attractive *** alignment-free statistics have been demonstrated in high performance and efficiency in wholegenome and transcriptome *** adapt k-mer statistics for HGT detection,we developed two aggregative statistics T^(S)_(sum ) and T^(*)_(sum),which subsample metagenome contigs by their representative regions,and summarize the regional D^(S) _(2) and D^(*)_(2)metrics by their upper *** systematically studied the aggregative statistics’power at different k-mer size using *** analysis showed that,in general,the power of T^(S)_(sum) and T^(*)_(sum) increases with sequencing coverage,and reaches a maximum power>80%at k=6,with 5%Type-i error and the coverage ratio>*** statistical power ofT^(S)_(sum) and T^(*)_(sum) was evaluated with realistic simulations of HGT mechanism,sequencing depth,read length,and base *** expect these statistics to be useful distance metrics for identifying HGT in metagenomic studies.

关键词： Alignment-free sequence comparison k-mer Horizontal gene transfer Statistical power

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