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Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： Ying Qin Kai-Fan Ji hui Liu Xiao-guang Yu Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set,1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test *** data preprocessing,we randomly cropped 128×128 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512×512 sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

Super-high bed sintering for iron ores: inhomogeneous phenomena and its mechanism during mineralizing

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Journal of Iron and Steel Research International 2024年第8期31卷 1850-1860页

作者： hui-bo Liu Liang-ping Xu Xi-duan Yang Zhong-lin Dong Qiang Zhong guang-hui Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous *** inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were *** results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,*** the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 *** and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm *** heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel *** inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid *** inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing *** mineralizing condition is the key for homogeneous super-high bed sintering.

关键词： Iron ore Super-high bed sintering Mineralization Material segregation Heat accumulation

Recent Advances of Porous Solids for Ultradilute CO_(2) Capture

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Chemical Research in Chinese Universities 2022年第1期38卷 18-30页

作者： LIU Ru-Shuai XU Shuang HAO guang-Ping LU An-hui State Key Laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024P.R.China

The urgency of dealing with global climate change caused by greenhouse gas(GHG) emissions is increasing as the carbon dioxide(CO_(2)) concentration in the atmosphere has reached a record high value of 416 ppm(parts per million). Technologies that remove CO_(2) from the surrounding air(direct air capture, DAC) could result in negative carbon emissions, and thus attracts increasing attention. The steady technical progress in adsorption-based CO_(2) separation greatly advanced the DAC, which largely relies on advanced sorbent materials. This review focuses on the latest development of porous solids for air capture;first discussed the main types of sorbents for air capture, which include porous carbons, zeolites, silica materials, and metal-organic frameworks(MOFs), particularly their modified counterparts. Then, we evaluated their performances, including uptake and selectivity under dry and humid CO_(2) streams for practical DAC application. Finally, a brief outlook on remaining challenges and potential directions for future DAC development is given.

关键词： Direct air capture Porous carbon CO_(2)capture Porous solid Adsorption

Yttrium-catalyzed cis-1,4-Selective Polymerization of 2-(4-Halophenyl)-1,3-butadienes and Their Copolymerization with Isoprene

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Chinese Journal of Polymer Science 2021年第3期39卷 309-315,I0005页

作者： Jian-Ming huang Chang-guang Yao Shi-hui Li Dong-Mei Cui State Key Loboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022Chino School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Polymerization of 2-(4-halophenyl)-1,3-butadiene(2-XPB) and their copolymerization with isoprene using a yttrium catalyst have been examined. The β-diketiminato yttrium bis(alkyl) complex(1) activated by [Ph_3 C][B(C_(6) F_(5))_(4)] and Ali Bu3 shows high cis-1,4-selectivity(>98%) for the polymerization of 2-XPB(2-XPB = 2-FPB, 2-Cl PB and 2-Br PB) to afford halogenated plastic poly(dienes) with glass transition temperatures of30–55 ℃. Moreover, the copolymerization of 2-XPB with isoprene(IP) has also been achieved by this catalyst, and the insertion ratios of 2-XPB can be facilely tuned in a full range of 0%–100% simply by changing the 2-XPB-to-IP ratio. Quantitative hydrogenation of cis-1,4-poly(2-XPB) results in perfect alternating ethylene-halostyrene copolymers, and an alternating copolymer of 4-vinylbenzoic acid with ethylene is obtained by a consecutive reaction of ethylene-4-bromostyrene copolymer with ^(n)Bu Li, CO_(2) and HCl.

关键词： cis-1,4-Selective Coordination(co)polymerization Poly(dienes) Alternating copolymer Post-polymerization modification

Study of oxidic and sulfded selective hydrodesulfurization catalysts for gasoline using Raman spectroscopy

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Chinese Chemical Letters 2013年第12期24卷 1041-1044页

作者： hui Yuan Qiherima guang-Tong Xu hui-Feng Li Li-Jun Lu Research Institute of Petroleum Processing SINOPEC The Institute for Chemical Physics Beijing Institute of Technology Inner Mongolia Medical College

A series of CoMo/Al2O3 catalysts for selective hydrodesulfurization （HDS） of gasoline were studied with Raman spectroscopy, a powerful method that creates specific signals for the states and the distributions of oxidic precursors and sulfided active phases. The higher the Mo and Co, the lower the tetrahedrally coordinated molybdate, and the higher the polymolybdate. But the amount of polymolybdate decreased when CoMoO4 appeared. Cobalt-promoted polymolybdate was the precursor, and its relative content correlated well with the HDS selectivity. For sulfided catalysts, adding the cobalt-promoter led to local distortion-disorder of the MoS2 structure and the formation of a CoMoS phase. This method can provide important information for designing new industrial selective-HDS catalvsts.

关键词： Raman spectroscopy Co-Mo/Al2O3 HDS selectivity

Epigenetic regulation of aging:implications for interventions of aging and diseases

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Signal Transduction and Targeted Therapy 2022年第12期7卷 4283-4304页

作者： Kang Wang huicong Liu Qinchao hu Lingna Wang Jiaqing Liu Zikai Zheng Weiqi Zhang Jie Ren Fangfang Zhu guang-hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of Sciences100101 BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of Sciences100101 BeijingChina University of Chinese Academy of Sciences 100049 BeijingChina School of Biomedical Engineering Shanghai Jiao Tong University200030 ShanghaiChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for Bioinformation100101 BeijingChina Hospital of Stomatology Sun Yat-sen University510060 GuangzhouChina guangdong Provincial Key Laboratory of Stomatology Guanghua School of StomatologySun Yat-sen University510060 GuangzhouChina Institute for Stem Cell and Regeneration Chinese Academy of Sciences100101 BeijingChina Advanced Innovation Center for human Brain Protection National Clinical Research Center for Geriatric DisordersXuanwu HospitalCapital Medical University100053 BeijingChina Beijing Institute for Stem Cell and Regenerative Medicine 100101 BeijingChina

Aging is accompanied by the decline of organismal functions and a series of prominent hallmarks,including genetic and epigenetic *** aging-associated epigenetic changes include DNA methylation,histone modification,chromatin remodeling,non-coding RNA(ncRNA)regulation,and RNA modification,all of which participate in the regulation of the aging process,and hence contribute to aging-related ***,understanding the epigenetic mechanisms in aging will provide new avenues to develop strategies to delay ***,aging interventions based on manipulating epigenetic mechanisms have led to the alleviation of aging or the extension of the lifespan in animal *** molecule-based therapies and reprogramming strategies that enable epigenetic rejuvenation have been developed for ameliorating or reversing aging-related *** addition,adopting health-promoting activities,such as caloric restriction,exercise,and calibrating circadian rhythm,has been demonstrated to delay ***,various clinical trials for aging intervention are ongoing,providing more evidence of the safety and efficacy of these ***,we review recent work on the epigenetic regulation of aging and outline the advances in intervention strategies for aging and age-associated diseases.A better understanding of the critical roles of epigenetics in the aging process will lead to more clinical advances in the prevention of human aging and therapy of aging-related diseases.

关键词： aging prevention hence

Comparison of two reliability models for performance degradation analysis

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航空动力学报 2015年第7期30卷 1632-1637页

作者： WANG Zhi-hua ZANG guang-kui ZHANG Yong-bo FU hui-min Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics

In order to investigate the general reliability assessment methods based on performance degradation data,two commonly used stochastic process approaches,bilinear process method and random-effect model were *** procedure and effectiveness of these two methodologies were studied and ***,the two approaches were illustrated through practical *** residual plots and the 10th percentile curves of the two methods were presented to demonstrate the comparative *** randomeffect model yielded more volatile residuals and a lower and unsafe 10th percentile *** the bilinear process model can be concluded to derive more reasonable results due to its one-stage estimation property.

关键词： degradation analysis reliability assessment stochastic process bilinear independent increment process random-effect model

Altered gut microbiota composition in children and their caregivers infected with the SARS‑CoV‑2 Omicron variant

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World Journal of Pediatrics 2023年第5期19卷 478-488页

作者： Yi‑Zhong Wang Jian‑Guo Zhou Yan‑Ming Lu hui hu Fang‑Fei Xiao Ting Ge Xing Wang Lu Zheng Lian‑hu Yu Jun Le hui Yu guang‑Jun Yu Qiang Xia Ting Zhang Wen‑Hao Zhou Department of Gastroenterology Hepatologyand NutritionShanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong University355 Luding RoadShanghai 200062China Gut Microbiota and Metabolic Research Center Institute of Pediatric InfectionImmunity and Critical Care MedicineSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Neonatology Children’s Hospital of Fudan UniversityShanghaiChina Department of Pediatrics Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Infectious Diseases Children’s Hospital of Fudan UniversityShanghaiChina Department of Liver Surgery Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Shanghai Key Laboratory of Birth Defects Department of NeonatologyMolecular Medical CenterChildren’s Hospital of Fudan University399 Wanyuan RoadShanghai 201101China

Background Gut microbiota alterations have been implicated in the pathogenesis of coronavirus disease 2019(COVID-19).This study aimed to explore gut microbiota changes in a prospective cohort of COVID-19 children and their asymptomatic caregivers infected with the severe acute respiratory syndrome coronavirus type 2(SARS-CoV-2)Omicron *** A total of 186 participants,including 59 COVID-19 children,50 asymptomatic adult caregivers,52 healthy children(HC),and 25 healthy adults(HA),were recruited between 15 April and 31 May *** gut microbiota composition was determined by 16S rRNA gene sequencing in fecal samples collected from the *** microbiota functional profling was performed by using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)*** The gut microbiota analysis of beta diversity revealed that the fecal microbial community of COVID-19 children remained far distantly related to *** relative abundances of the phyla Actinobacteria and Firmicutes were decreased,whereas Bacteroidetes,Proteobacteria,and Verrucomicrobiota were increased in COVID-19 *** from COVID-19 children exhibited notably lower abundances of the genera Blautia,Bifdobacterium,Fusicatenibacter,Streptococcus,and Romboutsia and higher abundances of the genera Prevotella,Lachnoclostridium,Escherichia-Shigella,and Bacteroides than those from *** enterotype distributions of COVID-19 children were characterized by a high prevalence of enterotype *** changes in gut microbiota compositions were observed in asymptomatic ***,the microbial metabolic activities of KEGG(Kyoto Encyclopedia of Genes and Genomes)and COG(cluster of orthologous groups of proteins)pathways were perturbed in feces from subjects infected with the SARS-CoV-2 Omicron *** Our data reveal altered gut microbiota compositions in both COVID-19 children and their asymptomatic caregivers infected with

关键词： Caregivers Children Coronavirus disease 2019(COVID-19) Gut microbiota Severe acute respiratory syndrome coronavirus type 2(SARS-CoV-2)

A Method Based on Multi-Body Dynamic Analysis for A Floating Two-Stage Buffer Collision-Prevention System Under Ship Collision Loads

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China Ocean Engineering 2021年第6期35卷 828-840页

作者： LU Kai CHEN Xu-jun YUAN hui huANG Heng WU guang-huai College of Field Engineering Army Engineering University of PLANanjing 210007China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211800China Nanjing guangbo Engineering Technology Co.LTD Nanjing 210046China People’s Liberation Army of China 32184 Nanjing 211100China

The collision of ships poses a great threat to the piers in navigable *** kinetic energy of the moving ship can be consumed not only with the structural deformation,but also with tensile force from the proposed Floating Two-stage Buffer Collision-Prevention System(FTBCPS).The actual anti-collision effect of the current designed FTBCPS can be evaluated by the dynamic *** construction method of 3D model is introduced,and the system initial state is *** transformation matrix and the basic kinematics vector are given,and the system basic dynamics equation is then *** mechanical analysis on each component is carried out,and the detailed process of numerical simulation is also *** simulation results indicate that collision direction and collision position have a great influence on the system kinematic *** pier faces the greatest threat when a ship hits the floater on the front beam in a nearly vertical direction,or on the side beam in a larger course *** study shows that the current designed FTBCPS can make full use of the fracture tensile property of polyester ropes and keep the tensile force acted on pier within its bearable range at the same *** collision direction has a significant effect on the dynamic response of the colliding bodies,but no failure appeared in the simulations,which indicates that the current designed FTBCPS can protect bridge piers of all cases for the 5000-t ship with a velocity smaller than 5 m/s in navigable waters.

关键词： bridge engineering Floating Two-stage Buffer Collision-Prevention System dynamics response compression force anti-collision tensile force anti-collision