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48篇 您的检索式:作者名="Siqi Ma"
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1Air pollution characteristics and their relationship with emissions and meteorology in the Yangtze River Delta region during 2014–2016显示文摘With rapid economic growth and urbanization, the Yangtze River Delta(YRD) region in China has experienced serious air pollution challenges. In this study, we analyzed the air pollution characteristics and their relationship with emissions and meteorology in the YRD region during 2014–2016. In recent years, the concentrations of all air pollutants, except O3,decreased. Spatially, the PM2.5, PM10, SO2, and CO concentrations were higher in the northern YRD region, and NO2 and O3 were higher in the central YRD region. Based on the number of non-attainment days(i.e., days with air quality index greater than 100), PM2.5 was the largest contributor to air pollution in the YRD region, followed by O3, PM10, and NO2.However, particulate matter pollution has declined gradually, while O3 pollution worsened.Meteorological conditions mainly influenced day-to-day variations in pollutant concentrations. PM2.5 concentration was inversely related to wind speed, while O3 concentration was positively correlated with temperature and negatively correlated with relative humidity.The air quality improvement in recent years was mainly attributed to emission reductions.During 2014–2016, PM2.5, PM10, SO2, NOx, CO, NH3, and volatile organic compound(VOC)emissions in the YRD region were reduced by 26.3%, 29.2%, 32.4%, 8.1%, 15.9%, 4.5%, and0.3%, respectively. Regional transport also contributed to the air pollution. During regional haze periods, pollutants from North China and East China aggravated the pollution in the YRD region. Our findings suggest that emission reduction and regional joint prevention and control helped to improve the air quality in the YRD region.Tao Ma Fengkui Duan Kebin He Yu Qin Dan Tong Guannan Geng Xuyan Liu Hui Li Shuo Yang Siqi Ye Beiyao Xu Qiang Zhang Yongliang Ma 2019Journal of Environmental Sciences2019,31,9:26
2Characteristics and Cause Analysis of Heavy Haze in Changchun City in Northeast China显示文摘Northeast China has been reported as having serious air pollution in China with increasing occurrences of severe haze episodes. Changchun City, as the center of Northeast China, has longstanding industry and is an important agricultural base. Additionally, Changchun City has a long winter requiring heating of buildings emitting pollution into the air. These factors contribute to the complexity of haze pollution in this area. In order to analyze the causes of heavy haze, surface air quality has been monitored from 2013 to 2015. By using satellite and meteorological data, atmospheric pollution status, spatio-temporal variations and formation have been analyzed. Results indicated that the air quality in 88.9% of days exceeding air quality index(AQI) level-1 standard(AQI >50) according to the National Ambient Air Quality Standard(NAAQS) of China. Conversely, 33.7% of the days showed a higher level with AQI > 100. Extreme haze events(AQI > 300) occurred frequently during agricultural harvesting period(from October 10 to November 10), intensive winter heating period(from Late-December to February) and period of spring windblown dust(April and May). Most daily concentrations of gaseous pollutants, i.e., NO_2(43.8 μg/m^3), CO(0.9 mg/m^3), SO_2(37.9 μg/m^3), and O_3(74.9 μg/m^3) were evaluated within level-1 concentration limits of NAAQS standards. However, particulate matter(PM_(2.5) and PM10) concentrations(67.3 μg/m^3 and 115.2 μg/m^3, respectively) were significantly higher than their level-1 limits. Severe haze in spring was caused by offsite transported dust and windblown surface soil. Heavy haze periods during fall and winter were mainly formed by intensive emissions of atmospheric pollutants and steady weather conditions(i.e., low wind speed and inversion layer). The overlay emissions of widespread straw burning and coal combustion for heating were the dominant factors contributing to haze in autumn, while intensive coal burning during the coldest time was the primary component of total emissions. In addition, general emissions including automobile exhaust, road and construction dust, residential and industrial activities, have significantly increased in recent years, making heavy haze a more frequent occurrence. Therefore, both improved technological strategies and optimized pollution management on a regional scale are necessary to minimize emissions in specified seasons in Changchun City, as well as comprehensive control measures in Northeast China.MA Siqi CHEN Weiwei ZHANG Shichun TONG Quansong BAO Qiuyang GAO Zongting 2017Chinese Geographical Science2017,27,6:8
3Reversible Histone H2B Monoubiquitination Fine-Tunes Abscisic Acid Signaling and Drought Response in Rice显示文摘Histone H2B monoubiquitination (H2Bub1) plays important roles in several physiological and developmental processes, but its roles in the regulation of plant stress responses remain elusive. Here, we report that H2Bub1 is crucially involved in abscisic acid (ABA) signaling and drought response in rice. We found that rice HISTONE MONOUBIQUITINATION2 (OsHUB2), an E3 ligase for H2Bub1, in teracted with OsbZIP46, a key transcription factor regulating ABA signaling and drought response in rice. Genetic analyses suggest that OsHUB2, upregulated by drought and ABA, positively modulates ABA sensitivity and drought resistance. The H2Bub1 levels were in creased in the target genes of OsbZIP46 under the drought stress and ABA treat- merits, which were positively correlated with their increased expression levels. Interestingly, MODD, a reported suppressor of ABA signaling and drought resistance by mediating OsbZIP46 deactivation and degradation, could reduce the H2Bub1 levels in the target genes of OsbZIP46 by recruiting a putative deubiquitinase OsOTLD1 . Suppression of OsOTLD1in vivo resulted in increased H2Bub1 levels and expression of OsbZIP46 target genes. Collectively, these fin dings established an elaborate mecha nism of histone monoubiquitination in the fine-turning of ABA signaling and drought response by balancing H2Bub1 deposition and removal.Siqi Ma Ning Tang Xu Li Yongjun Xie Denghao Xiang Jie Fu Jianqiang Shen Jun Yang Haifu Tu Xianghua Li Honghong Hu Lizhong Xiong 2019Molecular Plant2019,12,2:7
4Regional Characteristics and Causes of Haze Events in Northeast China显示文摘Northeast China experiences severe atmospheric pollution, with an increasing occurrence of heavy haze episodes. However, the underlying forces driving haze formation during different seasons are poorly understood. In this study, we explored the spatio-temporal characteristics and causes of haze events in Northeast China by combining a range of data sources(i.e., ground monitoring, satellite-based products, and meteorological products). It was found that the ‘Shenyang-Changchun-Harbin(SCH)'city belt was the most polluted area in the region on an annual scale. The spatial distribution of air quality index(AQI) values had a clear seasonality, with the worst pollution occurring in winter, an approximately oval-shaped polluted area around western Jilin Province in spring, and the best air quality occurring in summer and most of the autumn. The three periods that typically experienced intense haze events were Period I from mid-October to mid-November(i.e., late autumn and early winter), Period II from late-December to February(i.e., the coldest time in winter), and Period III from April to mid-May(i.e., spring). During Period I, strong PM_(2.5) emissions from seasonal crop residue burning and coal burning for winter heating were the dominant reasons for the occurrence of extreme haze events(AQI > 300). Period II had frequent heavy haze events(200 < AQI < 300) in the coldest months of January and February, which were due to high PM_(2.5) emissions from coal burning and vehicle fuel consumption, a lower atmospheric boundary layer, and stagnant atmospheric conditions. Haze events in Period III, with high PM_(10) concentrations, were primarily caused by the regional transportation of windblown dust from degraded grassland in central Inner Mongolia and bare soil in western Jilin Province. Local agricultural tilling could also release PM_(10) and enhance the levels of windblown dust from tilled soil. Better control of coal burning, fuel consumption, and crop residue burning in winter and autumn is urgently needed to address the haze problem in Northeast China.CHEN Weiwei ZHANG Shichun TONG Quansong ZHANG Xuelei ZHAO Hongmei MA Siqi XIU Aijun HE Yuexin 2018Chinese Geographical Science2018,28,5:7
5Design and Analysis of Double One Out of Two with a Hot Standby Safety Redundant Structure显示文摘In the rail transit system,the running foundation of the computer control system is required to be highly reliable,available and safe.A redundant system structure of double one out of two with a hot standby applied to the safety computer platform of the train control system is proposed in this paper.Considering the common cause failure,fault diagnosis rate,repair rate and switching success rate,the Markovian approach is adopted for modeling four safety redundant structures,including two out of three,double one out of two,one out of two with a hot standby and double one out of two with a hot standby.The calculation of the failure rate and PFH values is carried out with MATLAB to evaluate the reliability,safety and influencing factors of each structure.The final conclusion is that double one out of two with a hot standby structure can be best in the aspect of both reliability and safety with appropriate DC andβparameters.WEN Jiakun CAO Yuan MA Lianchuan DU Siqi 2020Chinese Journal of Electronics2020,29,3:4
6Tunable luminescence,energy transfer and excellent thermal stability of SrMg2(PO4)2:Ce^3+,Tb^3+ phosphors for LEDs显示文摘A series of novel SrMg2(PO4)2:Ce^3+,Tb^3+(SMP:Ce^3+,Tb^3+)phosphors with tunable emission spectra were produced via high temperature solid phase method.XRD,fluorescence spectrum and fluorescence lifetime for SMP:Ce^3+,Tb^3+were studied in detail.Under the excitation at 308 nm,SMP:Ce^3+,Tb^3+samples can emit high efficiency tunable blue-green light by controlling the proportion of dopant concentration.Through the spectral overlap and the regular change of fluorescence lifetime,it is proved that there is a significant energy transfer between Ce^3+and Tb^3+in SMP matrix and the energy transfer mechanism is determined to be an electric dipole-dipole interaction with energy transmission efficiency of 55%.In additional,Commission International de L’Eclairage(CIE)color coordinates and thermal stability were studied.All above findings suggest that SMP:Ce^3+,Tb^3+can be regarded as the potential bluish green phosphor for LED applications.Wanxin Mi Jun Zheng Peng Qiao Lili Cao Siqi Chu Hongping Ma 2021Journal of Rare Earths2021,39,1:4
7Recent advances in fire-retardant rigid polyurethane foam显示文摘Driven by global environmental concerns,many efforts have been made to develop halogen-free flame retardants for rigid polyurethane foam(RPUF).These environmentally benign flame retardants are mainly divided into(i)reactive,(ii)additive,and(iii)coating types.The last decade has witnessed great progress of these three strategies,which enhance the fire safety of RPUF and maintain even improve the thermal insulation properties.This comprehensive review focuses on the up-to-date design of the reactive,additive,and coating flame retardants,and their effects on flame retardancy and thermal conductivity of RPUF.Moreover,the practical applications of the as-prepared flame-retardant RPUFs are highlighted.Finally,key challenges associated with these three kinds of flame retardants are discussed and future research opportunities are also proposed.Menghe Zhu Zhewen Ma Lei Liu Jianzhong Zhang Siqi Huo Pingan Song 2022Journal of Materials Science & Technology2022,,17:3
8Influence of floc dynamic protection layer on alleviating ultrafiltration membrane fouling induced by humic substances显示文摘Cake layer formation is inevitable over time for ultrafiltration(UF)membrane-based drinking water treatment.Although the cake layer is always considered to cause membrane fouling,it can also act as a'dynamic protection layer',as it further adsorbs pollutants and dramatically reduces their chance of getting to the membrane surface.Here,the UF membrane fouling performance was investigated with pre-deposited loose flocs in the presence of humic acid(HA).The results showed that the floc dynamic protection layer played an important role in removing HA.The higher the solution pH,the more negative the floc charge,resulting in lower HA removal efficiency due to the electrostatic repulsion and large pore size of the floc layer.With decreasing solution pH,a positively charged floc dynamic protection layer was formed,and more HA molecules were adsorbed.The potential reasons were ascribed to the smaller floc size,greater positive charge,and higher roughness of the floc layer.However,similar membrane fouling performance was also observed for the negative and positive floc dynamic protection layers due to their strong looseness characteristics.In addition,the molecular weight(MW)distribution of HA also played an important role in UF membrane fouling behavior.For the small MW HA molecules,the chance of forming a loose cake layer was high with a negatively charged floc dynamic protection layer,while for the large MW HA molecules it was high with a positively charged floc dynamic protection layer.As a result,slight UF membrane fouling was induced.Baiwen Ma Siqi Wu Bodong Wang Zenglu Qi Yaohui Bai Huijuan Liu Jiuhui Qu Ruijun Wu 2020Journal of Environmental Sciences2020,32,4:2
9The effect of multiple pairs of meta-dicarboxyl groups on molecular self-assembly and the selective adsorption of coronene by hydrogen bonding and van der Waals forces显示文摘The prediction of two-dimensional molecular self-assembly structures has always been a problem to be solved.The molecules with meta-dicarboxyl groups can self-assemble into a specific hexagonal cavity,which has an important influence on the prediction of molecular self-assembly structures and the application of functional molecules with meta-dicarboxyl groups.Two kinds of molecules with four pairs of meta-dicarboxyl groups,1,3,6,8-tet「akis(3,5-isophthalic acid)pyrene(H_(8)TIAPy)and 4′,4′',4′'',4''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1′-biphenyl]-3,5-dicarboxylic acid))(H8ETTB)molecules were chosen to observe the self-assembly behavior at the heptanoic acid/highly oriented pyrolytic graphite(HA/HOPG)interface.H8TIAPy molecules self-assembled into well-ordered quadrilateral structures and could be regulated into kagome networks with hexagonal pores by coronene(COR)molecules.H8ETTB molecules self-assembled into lamellar structures and transformed into acid-COR-acid-COR co-assembled structures at low concentration of COR solution and acid-COR dimer-acid-COR dimer co-assembled structures at high concentration of COR solution.The reason that H8ETTB molecules could not be regulated into hexagonal porous architecture was attributed to the steric hindrance by the similar length and width of H8ETTB molecules.The H8ETTB templates had stronger adsorption for COR than that of hexaphenylbenzene(HPB),regardless of the order of molecular introduction.Jianqiao Li Wendi Luo Siqi Zhang Chunyu Ma Xunwen Xiao Wubiao Duan Qingdao Zeng 2022Nano Research2022,15,2:2
10Characterization of microbial communities in sediments of the South Yellow Sea显示文摘Illumina sequencing and quantitative PCR(qPCR)based on the 16 S ribosomal RNA(rRNA)gene were conducted to characterize the vertical distribution of bacterial and archaeal communities in the sediments of two sites from the South Yellow Sea.Both bacterial and archaeal communities showed a clear stratified distribution with sediment depth.The microbial communities in the upper layers were distinct from those in the deeper layers;the relative abundances of sequences of Thaumarchaeota,Gammaproteobacteria,and Actinobacteria were higher in the upper than in the deeper sediments,whereas the sequences of Bathyarchaeia,Lokiarchaeota,Euryarchaeota,Chloroflexi,and Deltaproteobacteria were relatively more abundant in the deeper sediments.Sediment depth and total organic carbon(TOC)can significantly influence both the bacterial and archaeal communities.Furthermore,bacterial and archaeal groups potentially involved in nitrogen,sulfur,and methane metabolism were detected in both sites.In our study,both ammonia-oxidizing bacteria(Nitrospira)and ammonia-oxidizing archaea(Candidatus Nitrosopumilus)were responsible for ammonia oxidization.Additionally,sulfur-reducing bacteria SEEP-SRB1 forming consortia with anaerobic methane-oxidizing archaea ANME-2 a-2 b were capable of anaerobic methane oxidation(AOM)in the 3400-02 sediment samples.Ye CHEN Siqi LI Xiaoqing XU Manman MA Tiezhu MI Yu ZHEN Zhigang YU 2021Journal of Oceanology and Limnology2021,39,3:2
11The self-assembly and structural regulation of a hydrogen-bonded dimeric building block formed by two N-H…O hydrogen bonds on HOPG显示文摘The self-assembled behavior of an unsymmetric molecule(BCDTDA)with one imidazole group as center and benzoic acid group as functional group is studied,and the regulatory behaviors of coronene(COR)and three bipyridine derivatives(named BP,PEBP-C4 and PEBP-C8)on BCDTDA self-assembly structures are also investigated.Based on highly oriented pyrolytic graphite(HOPG)substrate,scanning tunneling microscopy(STM)is used to observe the variation of assembled behaviors at the solid-liquid interface.Because of the concentration effect,BCDTDA molecules can assemble into grids and Kagomés structures in the form of N–H…O hydrogen bonded dimers.BCDTDA molecules still maintain dimeric structures in the regulation of COR and BP molecules to BCDTDA self-assembly.However,PEBP-C4 and PEBP-C8 destroy the structure of the dimers,and form a variety of co-assembled structures with BCDTDA.Different guest molecules coordinate the host molecules differently,which makes the experiment more meaningful.Combined with density functional theory(DFT)calculation,the discovery of molecular interactions provides a promising strategy for the construction of functional nanostructures and devices.Peng Lei Lin Ma Siqi Zhang Jianqiao Li Linlin Gan Ke Deng Wubiao Duan Wei Li Qingdao Zeng 2023Chinese Chemical Letters2023,34,8:1
12Monitoring water color anomaly of lakes based on an integrated method using Landsat-8 OLI images显示文摘Water color is a crucial optical indicator of water quality,polluted water bodies often show water color anomalies.To comprehensively understand the occurrence of water color anomalies in inland lakes,an integrated method was designed using the hue angle based on the Forel-Ule Index(FUI)model,and other remote sensing indices,including the Turbid Water Index(TWI),Floating Algae Index(FAI),and Cyanobacteria and Macrophytes Index(CMI).Based on all available Landsat-8 OLI images from 2013 to 2020,continuous monitoring was conducted in three different lakes in the middle of the Yangtze River,China.The results demonstrated that:(1)The proposed method can accurately identify algal blooms,high sediment loads,and eutrophication from the abnormal water color areas;(2)The calculated hue angles of sediment-dominated water were significantly higher than those of algal blooms and aquatic vegetation,providing a noticeable visual discoloration of water;(3)These water color anomalies exhibited significant correlations with the water quality and environmental conditions.This study serves as an example for accurate and spatially continuous assessment of water color anomaly and supports practical information to facilitate local water environment conservation.Xiaoqin Yang Ruqing Tong Li Ma Jian Li Siqi Wang Liqiao Tian 2022International Journal of Digital Earth2022,15,1:1
13No tillage outperforms conventional tillage under arid conditions and following fertilization显示文摘Reduced tillage practices present a tool that could sustainably intensify agriculture.The existing literature,however,lacks a consensus on how and when reduced tillage practices should get implemented.We reanalyzed here an extensive dataset comparing how regular tillage practices(i.e.,conventional tillage)impacted yield of eight crops compared to stopping tillage altogether(i.e.,no-tillage practice).We observed that aridity and fertilization favored no tillage over conventional tillage whereas conventional tillage performed better under high fertility settings.We further show that the responses are consistent across the crops.Our reanalysis complements the original and fills a gap in the literature questioning the conditions under which reducing tillage presents a viable alternative to common tillage practices.Stavros D.Veresoglou Junjiang Chen Xuheng Du Qi Fu QingLiu Geng Chenyan Huang Xilin Huang Nan Hu Yiming Hun Guolin C.Li Zhiman Lin Zhiyu Ma Yuyi Ou Shuo Qi Haitian Qin Yingbo Qiu Xibin Sun Ye Tao YiLing Tian Jie Wang Lingxiao Wu Ziwei Wu Siqi Xie Ao Yang Dan Yang Chen Zeng Ying Zeng RuJie Zhang 2023Soil Ecology Letters2023,5,1:1
14Generative artificial intelligence and its applications in materials science:Current situation and future perspectives显示文摘Generative Artificial Intelligence(GAI)is attracting the increasing attention of materials community for its excellent capability of generating required contents.With the introduction of Prompt paradigm and reinforcement learning from human feedback(RLHF),GAI shifts from the task-specific to general pattern gradually,enabling to tackle multiple complicated tasks involved in resolving the structure-activity relationships.Here,we review the development status of GAI comprehensively and analyze pros and cons of various generative models in the view of methodology.The applications of task-specific generative models involving materials inverse design and data augmentation are also dissected.Taking ChatGPT as an example,we explore the potential applications of general GAI in generating multiple materials content,solving differential equation as well as querying materials FAQs.Furthermore,we summarize six challenges encountered for the use of GAI in materials science and provide the corresponding solutions.This work paves the way for providing effective and explainable materials data generation and analysis approaches to accelerate the materials research and development.Yue Liu Zhengwei Yang Zhenyao Yu Zitu Liu Dahui Liu Hailong Lin Mingqing Li Shuchang Ma Maxim Avdeev Siqi Shi 2023Journal of Materiomics2023,9,4:1
15Ambient Temperature and Years of Life Lost:A National Study in China显示文摘Although numerous studies have investigated premature deaths attributable to temperature,effects of temperature on years of life lost(YLL)remain unclear.We estimated the relationship between temperatures and YLL,and quantified the YLL per death caused by temperature in China.We collected daily meteorological and mortality data,and calculated the daily YLL values for 364 locations(2013–2017 in Yunnan,Guangdong,Hunan,Zhejiang,and Jilin provinces,and 2006–2011 in other locations)in China.A time-series design with a distributed lag nonlinear model was first employed to estimate the location-specific associations between temperature and YLL rates(YLL/100,000 population),and a multivariate meta-analysis model was used to pool location-specific associations.Then,YLL per death caused by temperatures was calculated.The temperature and YLL rates consistently showed U-shaped associations.A mean of 1.02(95%confidence interval:0.67,1.37)YLL per death was attributable to temperature.Cold temperature caused 0.98 YLL per death with most from moderate cold(0.84).The mean YLL per death was higher in those with cardiovascular diseases(1.14),males(1.15),younger age categories(1.31 in people aged 65–74 years),and in central China(1.34)than in those with respiratory diseases(0.47),females(0.87),older people(0.85 in people R75 years old),and northern China(0.64)or southern China(1.19).The mortality burden was modified by annual temperature and temperature variability,relative humidity,latitude,longitude,altitude,education attainment,and central heating use.Temperatures caused substantial YLL per death in China,which was modified by demographic and regional characteristics.Tao Liu Chunliang Zhou Haoming Zhang Biao Huang Yanjun Xu Lifeng Lin Lijun Wang Ruying Hu Zhulin Hou Yize Xiao Junhua Li Xiaojun Xu Donghui Jin Mingfang Qin Qinglong Zhao Weiwei Gong Peng Yin Yiqing Xu Jianxiong Hu Jianpeng Xiao Weilin Zeng Xing Li Siqi Chen Lingchuan Guo Zuhua Rong Yonghui Zhang Cunrui Huang Yaodong Du Yuming Guo Shannon Rutherford Min Yu Maigeng Zhou Wenjun Ma 2021The Innovation2021,2,1:1
16Advances in NK cell production显示文摘Immunotherapy based on natural killer(NK)cells is a promising approach for treating a variety of cancers.Unlike T cells,NK cells recognize target cells via a major histocompatibility complex(MHC)-independent mechanism and,without being sensitized,kill the cells directly.Several strategies for obtaining large quantities of NK cells with high purity and high cytotoxicity have been developed.These strategies include the use of cytokine−antibody fusions,feeder cells or membrane particles to stimulate the proliferation of NK cells and enhance their cytotoxicity.Various materials,including peripheral blood mononuclear cells(PBMCs),umbilical cord blood(UCB),induced pluripotent stem cells(iPSCs)and NK cell lines,have been used as sources to generate NK cells for immunotherapy.Moreover,genetic modification technologies to improve the proliferation of NK cells have also been developed to enhance the functions of NK cells.Here,we summarize the recent advances in expansion strategies with or without genetic manipulation of NK cells derived from various cellular sources.We also discuss the closed,automated and GMP-controlled large-scale expansion systems used for NK cells and possible future NK cell-based immunotherapy products.Fang Fang Siqi Xie Minhua Chen Yutong Li Jingjing Yue Jie Ma Xun Shu Yongge He Weihua Xiao Zhigang Tian 2022Cellular & Molecular Immunology2022,19,4:0
17Improvement on a batch authenticated key agreement scheme显示文摘The rapid advancement in 5G networks calls for more key technologies to support.To promote its wide deployment and application,ultra-dense network(UDN)plays a significant part by providing high data rate and realizing seamless coverage and low delay.There have proposed many related works on 5G UDN,such as the literatures[1,2].However,UDN still faces some security challenges.For instance,it needs to guarantee the reliable and continuous connection and provide communication security.Qingfeng CHENG Ting CHEN Siqi MA Xinghua LI 2022Frontiers of Computer Science2022,16,2:0
18Coexistence of superconductivity and antiferromagentic order in Er_(2)O_(2)Bi with anti-ThCr_(2)Si_(2) structure显示文摘We investigated the coexistence of superconductivity and antiferromagnetic order in the compound Er_(2)O_(2)Bi with anti-ThCr_(2)Si_(2)-type structure through resistivity,magnetization,specific heat measurements and first-principle calculations.The superconducting transition temperature Tc of 1.23 K and antiferromagnetic transition temperature TN of 3 K are observed in the sample with the best nominal composition.The superconducting upper critical field H_(c2)(0)and electron-phonon coupling constantλe−ph in Er_(2)O_(2)Bi are similar to those in the previously reported non-magnetic superconductor Y_(2)O_(2)Bi with the same structure,indicating that the superconductivity in Er_(2)O_(2)Bi may have the same origin as in Y_(2)O_(2)Bi.The first-principle calculations of Er_(2)O_(2)Bi show that the Fermi surface is mainly composed of the Bi 6p orbitals both in the paramagnetic and antiferromagnetic state,implying minor effect of the 4f electrons on the Fermi surface.Besides,upon increasing the oxygen incorporation in Er_(2)O_(x)Bi,Tc increases from 1 to 1.23 K and TN decreases slightly from 3 K to 2.96 K,revealing that superconductivity and antiferromagnetic order may compete with each other.The Hall effect measurements indicate that hole-type carrier density indeed increases with increasing oxygen content,which may account for the variations of Tc and TN with different oxygen content.Lei Qiao Ning-hua Wu Tianhao Li Siqi Wu Zhuyi Zhang Miaocong Li Jiang Ma Baijiang Lv Yupeng Li Chenchao Xu Qian Tao Chao Cao Guang-Han Cao Zhu-An Xu 2021Frontiers of physics2021,16,6:0
19Data quantity governance for machine learning in materials science显示文摘Data-driven machine learning(ML)is widely employed in the analysis of materials structure-activity relationships,performance optimization and materials design due to its superior ability to reveal latent data patterns and make accurate prediction.However,because of the laborious process of materials data acquisition,ML models encounter the issue of the mismatch between a high dimension of feature space and a small sample size(for traditional ML models)or the mismatch between model parameters and sample size(for deep-learning models),usually resulting in terrible performance.Here,we review the efforts for tackling this issue via feature reduction,sample augmentation and specific ML approaches,and show that the balance between the number of samples and features or model parameters should attract great attention during data quantity governance.Following this,we propose a synergistic data quantity governance flow with the incorporation of materials domain knowledge.After summarizing the approaches to incorporating materials domain knowledge into the process of ML,we provide examples of incorporating domain knowledge into governance schemes to demonstrate the advantages of the approach and applications.The work paves the way for obtaining the required high-quality data to accelerate materials design and discovery based on ML.Yue Liu Zhengwei Yang Xinxin Zou Shuchang Ma Dahui Liu Maxim Avdeev Siqi Shi 2023National Science Review2023,10,7:0
20Extraction of Actinide Ion by Asymmetrical N,N′-dimethyl-N,N′-dioctyl-diglycolamide显示文摘In order to develop sustainable nuclear energy,agreat effort has been made for designing new extractants to selectively separate all actinides from nitric acid solutions of dissolution of spent fuel.Among those,tetraalkyldiglycolamide(TRDGA)ligands,such as N,N,N′,N′-tetra-octyldiglycolamide(TODGA)and N,N,N′,N′-tetra-isobutyl diglycolamide(TiBDGA),have shown great promise.YANG Suliang ZHANG Yan LIU Qian ZHOU Jin MA Siqi TIAN Guoxin 2018中国原子能科学研究院年报2018,,1:0
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