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Multivariate statistical and bioinformatic analyses for the seasonal variations of actinobacterial community structures in a drinking water reservoir

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Journal of Environmental Sciences 2024年第3期137卷 1-17页

作者： Haihan Zhang Sixuan Pan BenMa Tinglin Huang Dmitry B.Kosolapov Manli Ma xiang liu Huan liu Xiaoyan liu Shaanxi Key Laboratory of Environmental Engineering Key Laboratory of Northwest Water ResourceEnvironment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Papanin Institute for Biology of Inland Waters of Russian Academy of Sciences(IBIW RAS) 109BorokNekouzYaroslavl152742Russia

Actinobacterial community is a conspicuous part of aquatic ecosystems and displays an important role in the case of biogeochemical cycle,but little is known about the seasonal variation of actinobacterial community in reservoir ecological *** this study,the high-throughput techniques were used to investigate the structure of the aquatic actinobacterial community and its inducing water quality parameters in different *** results showed that the highest diversity and abundance of actinobacterial community occurred in winter,with Sporichthya(45.42%)being the most abundant genus and Rhodococcus sp.(29.32%)being the most abundant *** analysis and correlation analysis suggested that in autumn the dynamics of actinobacterial community were infuenced by more factors and Nocardioides ***2R5S2 was the potential keystone species which was negatively correlated with temperature(R=-0.72,Pfect the changes in actinobacterial community,and the dynamics of temperature,dissolved oxygen(DO),and turbidity are potential conspicuous factors infuencing seasonal actinobacterial community *** partial least squares path modeling further elucidated that the combined effects of DO and temperature not only in the diversity of actinobacterial community but also in other water qualities,while the physiochemical parameters(path coefficient=1.571,P<0.05)was strong environmental factors in natural mixture *** results strengthen our understanding of the dynamics and structures of actinobacterial community in the drinking water reservoirs and provide scientific guidance for further water quality management and protection in water sources.

关键词： Source water reservoir High-throughput sequencing Correlation analysis Network analysis Partial least squares path modeling

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Meta-Auto-Decoder:a Meta-Learning-Based Reduced Order Model for Solving Parametric Partial Differential Equations

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1096-1130页

作者： Zhanhong Ye xiang Huang Hongsheng liu Bin Dong Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China School of Computer Science and Technology University of Science and Technology of ChinaHefei 230027AnhuiChina Central Software Institute Huawei Technologies Co.LtdHangzhou 310007ZhejiangChina Center for Machine Learning Research Peking UniversityBeijing 100871China

Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational domains,*** reduced order modeling techniques accelerate the solution of the parametric PDEs by projecting them onto a linear trial manifold constructed in the ofline *** methods often need a predefined mesh as well as a series of precomputed solution snapshots,and may struggle to balance between the efficiency and accuracy due to the limitation of the linear *** the nonlinear representation of neural networks(NNs),we propose the Meta-Auto-Decoder(MAD)to construct a nonlinear trial manifold,whose best possible performance is measured theoretically by the decoder *** on the meta-learning concept,the trial manifold can be learned in a mesh-free and unsupervised way during the pre-training *** adaptation to new(possibly heterogeneous)PDE parameters is enabled by searching on this trial manifold,and optionally fine-tuning the trial manifold at the same *** numerical experiments show that the MAD method exhibits a faster convergence speed without losing the accuracy than other deep learning-based methods.

关键词： Parametric partial differential equations(PDEs) Meta-learning Reduced order modeling Neural networks(NNs) Auto-decoder

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Data driven reduced modeling for fluidized bed with immersed tubes based on PCA and Bi-LSTM neural networksAuthor links open overlay panel

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Particuology 2024年第8期91卷 1-18页

作者： Jiabin Fang Wenkai Cu Huang liu Huixin Zhang Hanqing liu Jinjia Wei xiang Ma Nan Zheng School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'anShaanxi 710049China

The fast and accurate reduced-order modeling of fluidized beds is a challenging task in the field of fluid dynamics,owing to their high dimensionality and nonlinear dynamic *** this study,a nonintrusive reduced order modeling method,the reduced order model based on principal component analysis and bidirectional long short-term memory networks(PBLSTM ROM),was developed to capture complex spatio-temporal dynamics of fluidized *** combining principal component analysis and Bidirectional long-short-term memory networks,the PBLSTM ROM effectively extracted dynamic evolution information without any prior knowledge of governing equations,enabling reduced-order modeling of unsteady flow *** PBLSTM ROM was validated using the solid volume fraction and gas velocity flow fields of a fluidized bed with immersed tubes,showing superior performance over both the PLSTM and PANN ROMs in accurately capturing temporal changes in the fluidization fields,especially in the region near immersed tubes where severe fluctuations ***,the PBLSTM ROM improved the simulation speed by five orders of magnitude compared to traditional computational fluid dynamics *** findings suggest that the PBLSTM ROM presents a promising approach for analyzing the complex fluid flows in engineering practice.

关键词： Reduced order modeling Fluidized bed Deep learning Bi-LSTM

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Structural Stability of Natural Magnesiochromite at High-Temperature-Pressure Conditions

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Journal of Earth Science 2024年第4期35卷 1196-1203页

作者： Shuyu Jin xiang Wu Yungui liu Yanfei Zhang Chao Wang State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan430074China College of Gems and Materials Hebei GEO UniversityShijiazhuang050031China

The podiform chromitites in the Luobusha ophiolite have been thought to experience a very deep formation,but the maximum depth is still an open ***,we have investigated the structural stability of natural magnesiochromite using the synchrotron-based powder X-ray diffraction and diamond anvil cells up to 48.6 GPa and 2450 *** results have shown that spinel-type magnesiochromite first decomposes into corundum-type‘Cr_(2)O_(3)’+B1-type‘MgO’at 11–14 GPa and 1250–1450 K,then modified ludwigite(mLd)-type‘Mg_(2)Cr_(2)O_(5)’+corundum-type‘Cr_(2)O_(3)’at 14.3–20.5 GPa and 1300–2000 K,and finally CaTi_(2)O_(4)-type phase at 24.5 *** the quenching procession from high-temperature-pressure conditions,the mLd-type phase appeared again and was kept at ambient *** also obtained the isothermal equation states of spinel-type and CaTi_(2)O_(4)-type phases,revealing the composition effect on their *** on the updated results,we propose chromitites could not experience pressure exceeding∼14.3 GPa(approximate maximum depth∼400 km)in the subduction-recycling genesis model.

关键词： chromite high-temperature and high-pressure phase transitions equation of state chromitites genesis

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Effect of slow shot speed on externally solidified crystal,porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy

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China Foundry 2024年第1期21卷 11-19页

作者： Wen-ning liu Wei Zhang Peng-yue Wang Yi-xian liu xiang-yi Jiao Ao-xiang Wan Cheng-gang Wang Guo-dong Tong Shou-mei Xiong School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing China FAW Group Co. Ltd.Changchun 130013China China FAW Foundry Co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg *** AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg *** elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-*** a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and *** an increase in slow shot speed,the size and number of ESCs and porosities significantly *** addition,the distribution of ESCs is more dispersed and the net-shrinkage *** tensile property is greatly improved by adopting a higher slow shot *** ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property

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Achieving single-cell-resolution lineage tracing in zebrafish by continuous barcoding mutations during embryogenesis

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Journal of Genetics and Genomics 2024年第9期51卷 947-956页

作者： Zhan liu Hui Zeng Huimin xiang Shanjun Deng Xionglei He State Key Laboratory of Biocontrol School of Life SciencesSun Yat-Sen UniversityGuangzhouGuangdong 510275China

Unraveling the lineage relationships of all descendants from a zygote is fundamental to advancing our understanding of developmental and stem cell ***,existing cell barcoding technologies in zebrafish lack the resolution to capture the majority of cell divisions during embryogenesis.A recently developed method,a substitution mutation-aided lineage-tracing system(SMALT),successfully reconstructed high-resolution cell phylogenetic trees for Drosophila ***,we implement the SMALT system in zebrafish,recording a median of 14 substitution mutations on a one-kilobase-pair barcoding sequence for one-day post-fertilization *** this system,we reconstruct four cell lineage trees for zebrafish fin cells,encompassing both original and regenerated *** tree consists of hundreds of internal nodes with a median bootstrap support of 99%.Analysis of the obtained cell lineage trees reveals that regenerated fin cells mainly originate from cells in the same part of the *** multiple times sampling germ cells from the same individual,we show the stability of the germ cell pool and the early separation of germ cell and somatic cell *** system offers the potential for reconstructing high-quality cell phylogenies across diverse tissues,providing valuable insights into development and disease in zebrafish.

关键词： Lineage tracing Cellular barcoding Zebrafishcell phylogeny Fin regeneration Germcell lineage

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Overshoot phenomena:Observation and simulation

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Earth and Planetary Physics 2024年第2期8卷 391-399页

作者： Ting feng MoRan liu ShiMin He xiang Wang Chen Zhou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

High-power O-mode radio waves can excite artificial instabilities in the F region,according to experiments conducted at the European Incoherent Scatter Science Association(EISCAT)heating *** main instabilities include the parametric decay instability(PDI),oscillating two-stream instability(OTSI),and thermal parametric instability(TPI).The PDI and OTSI not only compete with each other,but also compete with the TPI,leading to a two-stage overshoot phenomenon:a miniovershoot occurs on a millisecond time scale after pump-on,followed by the main *** gain insight into the miniovershoot via a generalized Zakharov model,whereas the main overshoot can be observed as an enhanced plasma line overshoot phenomenon in incoherent scatter radar *** can also observe that the zero-frequency ion line exists only in the initial heating period after a cold start and that the upshifted and downshifted ion lines behave irregularly in the *** simulation results show that competition between the PDI and OTSI leads to an initial peak,which we named the *** following processes,namely ion density caviton generation,and collapse and cascade in the development of the PDI,contribute to the miniovershoot phenomenon.

关键词： overshoot parametric decay instability oscillating two-stream instability competition

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Temperature prediction model in multiphase flow considering phase transition in the drilling operations

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Petroleum Science 2024年第3期21卷 1969-1979页

作者： Yang Zhang Yong-An Li xiang-Wei Kong Hao liu Teng-fei Sun College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100027China School of Petroleum Engineering Yangtze UniversityWuhan430000HubeiChina

The study considers gas compression properties,gas slippage,back pressure(BP),phase transition(PT),well depth,and differences in gas-liquid physical properties.A new temperature model for multiphase flow is proposed by considering phase transition in the drilling *** mathematical model of multiphase flow is solved using the finite difference method with annulus mesh division for grid nodes,and a module for multiphase flow calculation and analysis is *** results indicate that the temperature varies along the annulus with the variation of gas influx at the bottom of the *** the process of controlled pressure drilling,as gas slips along the annulus to the wellhead,its volume continuously expands,leading to an increase in the gas content within the annulus,and consequently,an increase in the pressure drop caused by gas *** temperature increases with the increase in BP and decreases in gas influx rate and wellbore *** gas influx,the thermal conductivity coefficient for the gas-drilling mud two phases is significantly weakened,resulting in a considerable change in temperature along the *** the context of MPD,the method of slightly changing the temperature along the annulus by controlling the back pressure is feasible.

关键词： Managed pressure drilling Phase transition Temperature Gas-drilling mud two phase

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A clean disposal method of carbide slag with carbon emission reduction:Used as a flux for iron ore sintering Author links open overlay panel

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Particuology 2024年第8期91卷 303-314页

作者： Hanxiao Meng Jiankang Wang xiang liu Kelang Jin Lei Zhang Hao Zhou State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou310027China

Limestone or quicklime is a necessary flux in the iron ore sintering *** production and application process will cause CO_(2) emissions and various environmental pollution,but this has not attracted enough *** slag(CS)is a calcium-rich solid waste produced in acetylene production,the harmless disposal of which is still incomplete,resulting in soil and groundwater *** study investigated the granulation characteristics and sintering performance of the sintering mixture with different proportions of *** results show that replacing limestone with an appropriate proportion of CS is promising and beneficial to the formation of high-quality bonding *** CS accounts for 75%of the total mass of CS and limestone,the tumbler index increases by 8.10%and the comprehensive index decreases only from 100 to 96.16,which is within the acceptable *** application of CS in iron ore sintering can achieve a clean disposal of it and a considerable carbon emission reduction,as the main component of which is Ca(OH)_(2).

关键词： Ironore sintering Carbide slag Flux Carbon emission Comprehensive index

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Filtering and regret network for spacecraft component segmentation based on gray images and depth maps

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Chinese Journal of Aeronautics 2024年第7期37卷 439-449页

作者： xiang liu Hongyuan WANG Zijian WANG Xinlong CHEN Weichun CHEN Zhengyou XIE Institute of Aeronautics Harbin Institute of TechnologyHarbin 150001China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100080China

Identifying and segmenting spacecraft components is vital in many on-orbit space missions,such as on-orbit maintenance and component *** depth maps with visual images has been proven effective in improving segmentation ***,existing methods ignore the noise and fallacy in collected depth maps,which interfere with the network to extract representative features,decreasing the final segmentation *** this end,this paper proposes a Filtering and Regret Network(FRNet)for spacecraft component *** FRNet incorporates filtering and regret mechanisms to suppress the abnormal depth response in shallow layers and selectively reuses the filtered cues in deep layers,avoiding the detrimental effects of low-quality depth information while preserving the semantic context inherent in depth ***,a two-stage feature fusion module is proposed,which involves information interaction and *** module effectively explores the feature correlation and unifies the multimodal features into a comprehensive ***,a large-scale spacecraft component recognition dataset is constructed for training and evaluating spacecraft component segmentation *** results demonstrate that the FRNet achieves a state-of-the-art performance with a mean Intersection Over Union(mIOU)of 84.13%and an average inference time of 133.2 ms when tested on an NVIDIA RTX 2080 SUPER GPU.

关键词： Spacecraft component recognition Multi-modal feature fusion Satellite dataset Intelligent systems Deep learning

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