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Diversity and dynamic response of anaerobic ammonia oxidation granular sludge
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作者 Jiahong Ye Xiang Li +6 位作者 Yan Yuan Yayi Wang Yong Huang junma Han Wang Pengze Dang Pei-ling Xu 《Journal of Environmental Sciences》 2025年第6期262-275,共14页
Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported insuccessfully operating Anammox systems, and its color is associated with sludge activity.However, in long-term operating systems, An... Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported insuccessfully operating Anammox systems, and its color is associated with sludge activity.However, in long-term operating systems, AnGS exhibits different sensory colors, physicalstructures, community structures, and denitrification performance, but the relationship betweenthem has not yet been elucidated.The AnGS of the Anammox system, which has beenin operation for more than a decade, can be divided into twomain categories: red and white.The specific Anammox activity (SAA) in conventional red AnGS increased continuously asthe particle size increased from <0.51 mm to 6.02 ± 0.84 mm. The SAA of white AnGS wereslightly lower than those of red AnGS with similarly-size granules but significantly higherthan AnGS with smaller red granules. Compared with red AnGS, the extracellular polymericsubstances of white AnGS were significantly reduced,mainly due to the higher intracellulariron content, resulting in lower heme c concentration. Thus, heme c may prove not to bean evaluative tool for measuring Anammox activity. Red and white AnGS, whether throughself-aggregation or adsorption by hydroxyl apatite and other carriers, will face the fate ofinternal voids during particle size growth. White AnGS exhibited amore complex microbialcommunity than red AnGS. Candidatus Brocadia was abundant in red AnGS and the abundanceincreased with increasing granule size. Candidatus Kuenenia and Candidatus Jetteniamade significant contributions to denitrification in white AnGS. This study provides a newperspective on particle selection for anammox engineering applications. 展开更多
关键词 Anaerobic ammonium oxidation granular sludge Sensory diversity Intracellular iron HEME Enzyme activity Microbial diversity
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Activation of peroxymonosulfate by sustainable biomass-based carbon nanotubes for controlling the spread of plant viruses in water environments
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作者 Jian Tang Yujie Wang +2 位作者 junma Yujie Chen Ming Chen 《Journal of Environmental Sciences》 2025年第3期99-112,共14页
With the increasing demand for water in hydroponic systems and agricultural irrigation,viral diseases have seriously affected the yield and quality of crops.By removing plant viruses in water environments,virus transm... With the increasing demand for water in hydroponic systems and agricultural irrigation,viral diseases have seriously affected the yield and quality of crops.By removing plant viruses in water environments,virus transmission can be prevented and agricultural production and ecosystems can be protected.But so far,there have been few reports on the removal of plant viruses in water environments.Herein,in this study,easily recyclable biomass-based carbon nanotubes catalysts were synthesized with varying metal activities to activate peroxymonosulfate(PMS).Among them,the magnetic 0.125Fe@NCNTs-1/PMS system showed the best overall removal performance against pepper mild mottle virus,with a 5.9 log_(10)removal within 1 min.Notably,the key reactive species in the 0.125Fe@NCNTs-1/PMS system is^(1)O_(2),which can maintain good removal effect in real water matrices(river water and tap water).Through RNA fragment analyses and label free analysis,it was found that this system could effectively cleave virus particles,destroy viral proteins and expose their genome.The capsid protein of pepper mild mottle virus was effectively decomposed where serine may be the main attacking sites by^(1)O_(2).Long viral RNA fragments(3349 and 1642 nt)were cut into smaller fragments(∼160 nt)and caused their degradation.In summary,this study contributes to controlling the spread of plant viruses in real water environment,which will potentially help protect agricultural production and food safety,and improve the health and sustainability of ecosystems. 展开更多
关键词 Pepper mild mottle virus Removal Plant virus spread Biomass-based carbon nanotubes Water environments
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A Two-Phase Paradigm for Joint Entity-Relation Extraction 被引量:2
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作者 Bin Ji Hao Xu +4 位作者 Jie Yu Shasha Li junma Yuke Ji Huijun Liu 《Computers, Materials & Continua》 SCIE EI 2023年第1期1303-1318,共16页
An exhaustive study has been conducted to investigate span-based models for the joint entity and relation extraction task.However,these models sample a large number of negative entities and negative relations during t... An exhaustive study has been conducted to investigate span-based models for the joint entity and relation extraction task.However,these models sample a large number of negative entities and negative relations during the model training,which are essential but result in grossly imbalanced data distributions and in turn cause suboptimal model performance.In order to address the above issues,we propose a two-phase paradigm for the span-based joint entity and relation extraction,which involves classifying the entities and relations in the first phase,and predicting the types of these entities and relations in the second phase.The two-phase paradigm enables our model to significantly reduce the data distribution gap,including the gap between negative entities and other entities,aswell as the gap between negative relations and other relations.In addition,we make the first attempt at combining entity type and entity distance as global features,which has proven effective,especially for the relation extraction.Experimental results on several datasets demonstrate that the span-based joint extraction model augmented with the two-phase paradigm and the global features consistently outperforms previous state-ofthe-art span-based models for the joint extraction task,establishing a new standard benchmark.Qualitative and quantitative analyses further validate the effectiveness the proposed paradigm and the global features. 展开更多
关键词 Joint extraction span-based named entity recognition relation extraction data distribution global features
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Discovery of Three Variable Stars in Direction toward NGC 4565 被引量:1
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作者 LeiLi HongWu +4 位作者 Xiao-BinZhang Ya-BoWu XuZhou Zhao-JiJiang junma 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2004年第5期411-414,共4页
We present the results of a variable star search in a field next to the edge-on galaxies NGC 4565 from the archive data of Beijing-Arizona-Taibei-Connecticut Multicolor Sky Survey. Three new variable stars were discov... We present the results of a variable star search in a field next to the edge-on galaxies NGC 4565 from the archive data of Beijing-Arizona-Taibei-Connecticut Multicolor Sky Survey. Three new variable stars were discovered. Based on spectra obtained from the 2.16m NAOC telescope, we identify two of these as RR Lyr stars and one as a special T Tauri star. 展开更多
关键词 stars: variables: RR Lyr stars: variables: T Tauris
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Preliminary Study on Pyrolysis of Polymethylsilsesquioxane by FT-IR and XPS
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作者 junma QingYangFENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第1期75-78,共4页
Changes of composition and structure of various samples of polymethylsilsesquioxane (PMSQ) pyrolysed at different temperature under flowing nitrogen were investigated by means of FT-IR and X-ray photoelectron spectros... Changes of composition and structure of various samples of polymethylsilsesquioxane (PMSQ) pyrolysed at different temperature under flowing nitrogen were investigated by means of FT-IR and X-ray photoelectron spectroscopy. Two temperature domains correspond to important changes in the chemical composition of PMSQ. The former (Tp < 500oC) is related to the transition from regular structure to irregular structure and the latter (Tp > 500oC) is associated with the organic-inorgnic transition. 展开更多
关键词 POLYMETHYLSILSESQUIOXANE PYROLYSIS X-ray photoelectron spectroscopy.
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Detailed study of B037 based on HST images
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作者 junma 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第5期524-536,共13页
B037 is of interest because it is both the most luminous and the most highly reddened cluster known in M31. Deep observations and high spatial resolution images with the Advanced Camera for Surveys on the Hubble Space... B037 is of interest because it is both the most luminous and the most highly reddened cluster known in M31. Deep observations and high spatial resolution images with the Advanced Camera for Surveys on the Hubble Space Telescope (HST) first showed that this cluster is crossed by a dust lane. Photometric data in the F606W and F814W filters obtained in this paper indicate that colors of (F606W - F814W) in the dust lane are redder-0.4 mag than ones in the other regions of B037. The HST images show that this dust lane seems to be contained in B037, instead of in the M31 disk or the Milky Way. As far as we know, the formation of dust requires gas with a rather high metallicity. However, B037 has a low metallicity of [Fe/H] =→1.07 ±0.20. So, it seems improbable that the observed dust lane is physically associated with B037. It is clear that the origin of this dust lane is worthy of future study. In addition, based on these images, we present the precise variation of ellipticity and position angle, and of surface brightness profile, and determine the structural parameters of B037 by fitting a single-mass isotropic King model. In the F606W filter, we derive the best-fitting scale radius r0 = 0.56±0.02" (= 2.16±0.08 pc), a tidal radius rt = 8.6±0.4I" (= 33.1±1.5 pc), and a concentration index c = log(rt/ro) = 1.19±0.02. In the F814W filter, we derive r0 = 0.56 4± 0.01H (_=2.16 ±0.04 pc), rt = 8.9 ±0.3" (= 34.3±1.2 pc), and c = log(rt/ro) = 1.20±0.01. The extinction-corrected central surface brightness is μ0 = 13.53±0.03 mag arcsec^-2 in the F606W filter, and 12.85±0.03 mag arcsec^-2 in the F814W filter. We also calculate the half-light radius at rh = 1.05±0.03"(= 4.04±0.12 pc) in the F606W filter and rh =1.07±0.01"(= 4.12±0.04 pc) in the F814W filter. In addition, we derived the complete magnitudes of B037 in the V and I bands by transforming the magnitudes from the ACS system to the standard system, which are in good agreement with previous ground-based broad- band photometry studies. 展开更多
关键词 galaxies: evolution -- galaxies: individual (M31) -- globular cluster:individual (B037)
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