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Recent progress on mechanisms,principles,and strategies for high-activity and high-stability.non-PGM fuel cell catalyst design

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Carbon Energy 2024年第5期6卷 25-52页

作者： yuping yuan y.n Zheng Dan luo Weibin qiu Jiantao Wang Xin Wang Zhongwei Chen GRInM(Guangdong)Institute of new Materials Technology FoshanChina Department of Chemical Engineering Waterloo Institute for NanotechnologyWaterloo Institute for Sustainable EnergyUniversity of WaterlooWaterlooOntarioCanada Guangdong Provincial Key Laboratory of nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangdongChina national Power Battery Innovation Center GRINM Group Co.Ltd.BeijingChina

The commercialization of a polymer membrane H2-O2 fuel cell and its widespread use call for the development of cost-effective oxygen reduction reaction(ORR)nonplatinum group metal(nPGM)***,to meet the requests for the real-world fuel cell application and replacing platinum catalysts,it still needs to address some challenges for nPGM catalysts regarding the sluggish ORR kinetics in the cathode and their poor durability in acidic *** response to these issues,numerous efforts have been made to study.nPGM catalysts both theoretically and experimentally,developed these into the atomically dispersed coordinated metal-nitrogen-carbon(M-n-C)form over the past *** this review,we present a comprehensive summary of recent advancements on nPGM catalysts with high activity and *** design strategies in terms of optimizing active-site density and enhancing catalyst stability against demetalization and carbon corrosion are *** is also emphasized the importance of understanding the mechanisms and principles behind those strategies through a combination of theoretical modeling and experimental ***,further understanding the mechanisms related to the active-site structure and the formation process of the single-atom active site under pyrolysis conditions is critical for active-site *** the active-site distance is the basic principle for improving catalyst activity through increasing the catalyst active-site *** studies for the catalyst deactivation mechanism and modeling stable active-site structures provide both mechanisms and principles to improve the nPGM catalyst ***,currently remained challenges and perspectives in the future on designing high-performance atomically dispersed nPGM catalysts toward fuel cell application are discussed.

关键词： batteries electrocatalysis energy storage and conversion fuel cells

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Clinical risk factors for preterm birth and evaluating maternal psychology in the postpartum period

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World Journal of Psychiatry 2024年第5期14卷 661-669页

作者： Jia-Jun Chen Xue-Jin Chen qiu-Min She Jie-Xi Li qiu-Hong luo Department of Clinical Laboratory Shenzhen Bao’an District Songgang People’s HospitalShenzhen 518000Guangdong ProvinceChina Department of Otolaryngology Head and neck Surgery Outpatient Shenzhen Children’s HospitalShenzhen 518000Guangdong ProvinceChina Department of Prevention and Health Care Shenzhen Bao’an District Songgang People’s HospitalShenzhen 518000Guangdong ProvinceChina Department of Obstetrics Shenzhen Bao’an District Songgang People’s HospitalShenzhen 518000Guangdong ProvinceChina

BACKGROUnD Although the specific pathogenesis of preterm birth(PTB)has not been thoroughly clarified,it is known to be related to various factors,such as pregnancy complications,maternal socioeconomic factors,lifestyle habits,reproductive history,environmental and psychological factors,prenatal care,and nutritional *** has serious implications for newborns and families and is associated with high mortality and ***,the prediction of PTB risk can facilitate early intervention and reduce its resultant adverse *** To analyze the risk factors for PTB to establish a PTB risk prediction model and to assess postpartum anxiety and depression in *** A retrospective analysis of 648 consecutive parturients who delivered at Shenzhen Bao’an District Songgang People’s Hospital between January 2019 and January 2022 was *** to the diagnostic criteria for premature infants,the parturients were divided into a PTB group(n=60)and a full-term(FT)group(n=588).Puerperae were assessed by the Self-rating Anxiety Scale(SAS)and Self rating Depression Scale(SDS),based on which the mothers with anxiety and depression symptoms were screened for further *** factors affecting PTB were analyzed by univariate analysis,and the related risk factors were identified by logistic *** According to univariate analysis,the PTB group was older than the FT group,with a smaller weight change and greater proportions of women who underwent artificial insemination and had gestational diabetes mellitus(Pn addition,greater proportions of women with reproductive tract infections and greater white blood cell(WBC)counts(Pngths in the second trimester and lower neutrophil percentages(Pn the PTB group than in the FT *** PTB group exhibited higher postpartum SAS and SDS scores than did the FT group(Pnumber of mothers experiencing anxiety and depress

关键词： Preterm birth Risk factors Postpartum psychological state Risk model Prediction

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Unexpected Diversity in Ecosystem nutrient Responses to Experimental Drought in Temperate Grasslands

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Phyton-International Journal of Experimental Botany 2024年第4期93卷 831-841页

作者： Biy.ng qiu niwu Te Lin Song yuan Shi Chuan qiu Xiaoan Zuo Qiang yu Jianqiang Qian Zhengwen Wang Honghui Wu Wentao luo School of Life Sciences Hebei UniversityBaoding071002China Liaoning northwest Grassland Ecosystem national Observation and Research Station Erguna Forest-Steppe Ecotone Research StationInstitute of Applied EcologyChinese Academy of SciencesShenyang110164China northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou730030China School of Grassland Science Beijing Forestry UniversityBeijing100083China College of Forestry Henan Agricultural UniversityZhengzhou450002China State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in northern China Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing100081China Key Laboratory of Arable Land Quality Monitoring and Evaluation Ministry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing100081China

The responses of ecosystem nitrogen (n) and phosphorus (P) to drought are an important component of globalchange studies. However, previous studies were more often based on site-specific experiments, introducing a significantuncertainty to synthesis and site comparisons. We investigated the responses of vegetation and soil nutrientsto drought using a network experiment of temperate grasslands in northern China. Drought treatment (66%reduction in growing season precipitation) was imposed by erecting rainout shelters, respectively, at the driest,intermediate, and wettest sites. We found that vegetation nutrient concentrations increased but soil nutrient concentrationsdecreased along the aridity gradient. Differential responses were observed under experimentaldrought among the three grassland sites. Specifically, the experimental drought did not change vegetation andsoil nutrient status at the driest site, while strongly reduced vegetation but increased soil nutrient concentrationsat the site with intermediate precipitation. On the contrary, experimental drought increased vegetation n concentrationsbut did not change vegetation P and soil nutrient concentrations at the wettest site. In general, the differentialeffects of drought on ecosystem nutrients were observed between manipulative and observationalexperiments as well as between sites. Our research findings suggest that conducting large-scale, consistent, andcontrolled network experiments is essential to accurately evaluate the effects of global climate change on terrestrialecosystem bio-geochemistry.

关键词： Climate change drought experiment precipitation nutrient cycles

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Reduction of dinitrogen to ammonia on doped three-atom clusters nb_(2)M(M=Sc to Cu & y to Ag)

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Rare Metals 2024年第8期43卷 3810-3818页

作者： Ran Cheng Chao-nan Cui Zhi-Xun luo Beijing national Laboratory for Molecular Science(BnLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy ***-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active *** a study of n2 activation and reduction on seventeen bimetallic nb_2M(M=Sc to Cu,and y to Ag) clusters was *** key processes for ammonia fixation(namely.nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(nb_2ni,nb_2Rh and nb_2Pd) are highlighted with outstanding catalytic *** d-σ and d-π~* orbital hybridizations between these metal clusters and n_(2) were demonstrated and the internal association with the n≡n bond activation was *** examining the ammonia synthesis on four chosen nb_(2)M clusters(M=Fe,ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these *** work not only clarifies the n_(2) reduction on the bimetallic nb_(2)M clusters,but also guides efficient bimetallic catalyst design.

关键词： Three-atom cluster catalysis Three-criteria strategy nitrogen fixation Ammonia synthesis Theoretical calculations

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Comparing the efficacy and safety of low,medium,and high dosages of selexipag for treating pulmonary hypertension:A systematic review and meta-analysis

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Animal Models and Experimental Medicine 2024年第1期7卷 56-70页

作者： Shang Wang yi y.n Jian Zhang Ping yuan Ci-Jun luo Hong-Ling qiu Hui-Ting Li Jian Xu Lan Wang Tian-Lan Li Rong Jiang Department of Cardio-Pulmonary Circulation Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghaiChina Heart Center and Shanghai Institute of Pediatric Congenital Heart Disease Shanghai Children's Medical CenterNational Children's Medical CenterShanghai Jiaotong University School of MedicineShanghaiChina Department of Respiratory and Critical Care Medicine The 416 Hospital of Nuclear IndustryThe Second Affiliated Hospital of Chengdu Medical CollegeChengduChina Department of Hematology The Affiliated Hospital of Qingdao UniversityQingdaoChina

Background:The maintenance dosage of selexipag is categorized as low,medium or *** order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypertension(PAH),we performed a sys-tematic review and ***:Studies assessing PAH risk stratification indices,such as the World Health Organization functional class(WHO-FC),six-minute walk distance(6MWD),n-terminal pro-B-type natriuretic peptide(nT-proBnP)level,right atrial pressure(RAP),cardiac index(CI)and mixed venous oxygen saturation(SvO2),were ***:Thirteen studies were *** led to improvements in the 6MWD(MD:24.20 m,95%CI:10.74-37.67),nT-proBnP(SMD:-0.41,95%CI:-0.79-0.04),CI(MD:0.47 L/min/m^(2),95%CI:0.17-0.77)and WHO-FC(OR:0.564,95%CI:0.457-0.697).Subgroup analysis demonstrated that all three dosages improved the 6MWD.A moderate dosage led to improvements in the CI(MD:0.30 L/min/m^(2),95%CI:0.15-0.46)and WHO-FC(OR:0.589,95%CI:0.376-0.922).Within 6 months of treatment,only the WHO-FC and CI were significantly improved(OR:0.614,95%CI:0.380-0.993;MD:0.30 L/min/m^(2),95%CI:0.16-0.45,respectively).More than 6 months of treatment significantly improved the 6MWD,WHO-FC and nT-proBnP(MD:40.87 m,95%CI:10.97-70.77;OR:0.557,95%CI:0.440-0.705;SMD:-0.61,95%CI:-1.17-0.05,respectively).Conclusions:Low,medium,and high dosages of selexipag all exhibited good *** treatment lasted for more than 6 months,selexipag exerted obvious effects,even in the low-dosage *** finding is important for guiding individualized treatments.

关键词： individualized treatments meta-analysis prostacyclin receptor agonist risk stratification systematic review

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Intraspecific floral colour variation in three Pedicularis species

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Plant Diversity 2024年第2期46卷 274-279页

作者： qiu-yu Zhang Zhe Chen Hang Sun y.ng niu State Key Laboratory of Plant Diversity and Specialty Crops Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China

Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging,reducing reproductive interference in natural *** extent of flower constancy is largely determined by the floral traits of co-flowering *** higher inter-specific and lower intraspecific differences of floral traits should contribute to a higher level of flower ***,previous studies mainly focused on interspecific difference,and the intraspecific variation(consistency)of floral traits received much less *** hypothesise that selection may favour lower intraspecific floral trait variation in communities composed of multiple co-flowering *** investigated the floral colour variation of three focal Pedicularis species that share pollinators in 19communities composed of either single or multiple Pedicularis *** was quantified using image-based colour analysis as perceived by *** found that most of the intrapopulation floral colour variation was below the colour discrimination threshold of bumblebees,imply.ng strongly constrained by the visual selection by *** to the hypothesis,there is no significant difference in intraspecific floral colour variation between different community *** may be due to the relatively large interspecific floral colour differences of most co-flowering *** influence of community context on intraspecific variation may be reflected in floral traits other than colours.

关键词： Flower constancy Floral colour variation Plantepollinator interactions Pollinator vision

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Caudal hematopoietic tissue supports definitive erythrocytes via epoa and is dispensable for definitive neutrophils

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Journal of Genetics and Genomics 2024年第6期51卷 669-672页

作者： Zhujuan Huang y.ngtai Xu Zhongkai qiu y.ny.n Jiang Jiaye Wu Qing Lin Sicong He Jianan y.Qu Jiahao Chen Jin Xu Innovation Centre of Ministry of Education for Development and Diseases School of MedicineSouth China University of TechnologyGuangzhouGuangdong 510006China Department of Biology School of Life SciencesSouthern University of Science and TechnologyShenzhenGuangdong 518055China Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyKowloonHongkong 999077China

The blood system originates from hematopoietic stem cells(HSCs),capable of self-renewal and differentiation,generating diverse blood cell types(Eaves,2015;Lucas,2021).The concept of the hematopoietic niche was first proposed in 1978(Schofield,1978),which is crucial for maintaining hematopoietic *** following studies,particularly in mammals,have utilized targeted genetic manipulation to identify and define these niches.

关键词： hematopoietic manipulation utilized

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Slow magnetic relaxation behaviors and diamagnetic dilution studies of a carboxyl bridged dinuclear dysprosium(Ⅲ) complex

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Journal of Rare Earths 2024年第11期42卷 2088-2096页

作者： Wenting Liu yibo qiu Weiqin Xu Manli Cao Xin Deng Weiquan Lin School of Chemistry and Materials Science Guangdong University of Education School of Chemistry and Chemical Engineering/Institute of Clean Energy and Materials Guangzhou University

By using a rigid bulky carboxylic ligand a-cy.nocinnamic acid（CCA）,a dinuclear dysprosium（Ⅲ） complex [Dy2（CCA）6（MeOH）4]（1） was *** crystal X-ray crystallography reveals that the two eight-coordinate dysprosium ions are bridged by four deprotonated carboxyl groups,forming a centrosymmetric paddle-wheel-1ike *** magnetic property measurements indicate that complex 1 displays field-induced slow magnetic *** temperature-dependent relaxation times can be fitted using Orbach and Raman processes with parameters of n=2.8（2）,C=27（8） s-1/K~n,τ0=5（2） × 10-10s and Ueff=40（3） *** studies on the diamagnetic yⅢ-diluted analogue[Dy0.206y1.794（CCA）6（MeOH）4]（2） reveal its slow magnetic relaxation behavior without external dc field and the antiferromagnetic coupling between the DyⅢions in *** on the obtained relaxation times of 2lead to the parameters of n=4.5（3）,C=0.7（2） s-1/K~n,τ0=2.8（2） × 10-9s and Ueff=38（2） *** results suggest that slow magnetic relaxation originates from the single-ion relaxation of DyⅢ***,the diamagnetic dilution can suppress other fast relaxation pathways at low temperature,on account of the elimination of magnetic coupling and dipolar *** initio calculations were then performed on the single DyⅢion species {yDy} and indicate that the first excited Kramers doublets（KDs）lie at ca.76 cm-1,which is slightly higher than the experimental *** intramolecular magnetic interactions were also calculated and indicate a weak ferromagnetic dipole-diploe magnetic interaction and an antiferromagnetic exchange coupling.

关键词： Diamagnetic dilution Dilanthanide complexes Rare earths Single-molecule magnets

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yolk-shell FeCu/nC electrocatalyst boosting high-performance zinc-air battery

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nano Research 2024年第9期17卷 7918-7925页

作者： Chen Liang Tianyu Zhang Shilun Sun Aijuan Han Zenghui qiu Haijun Xu Junfeng Liu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Mathematics&Physics Beijing University of Chemical TechnologyBeijing 100029China Beijing Bioprocess Key Laboratory Beijing University of Chemical TechnologyBeijing 100029China

Iron-nitrogen-carbon single-atom catalysts(Fe-n-C SACs)are widely acknowledged for their effective oxygen reduction activity,however,their activity requires further ***,additional structural optimization is necessary to enhance mass transport and achieve higher power density in practical ***,using ZIF-8 as a template,we synthesized yolk-shell catalysts featuring complex sites of Fe single atoms and Cu nanoclusters(y-FeCu/nC)via partial etching and liquid-phase *** synthesized y-FeCu/nC catalyst exhibits high specific surface area and mesoporous *** with the advantages of highly active sites and yolk-shell structure,the y-FeCu/nC catalyst demonstrated outstanding catalytic performance in the oxygen reduction reaction,achieving a half-wave potential(E_(1/2))of 0.97 V in 0.1 M *** a practical energy device,Zn-air battery(ZAB)assembled with y-FeCu/nC catalyst achieved a remarkable power density of 356.3 mW·cm^(-2),representing an improvement of approximately 28.5%compared to its solid FeCu/nC ***,it showcased impressive stability,surpassing all control samples.

关键词： atomic Fe-n4 sites Cu nanoclusters yolk-shell structure oxygen reduction reaction zinc-air battery

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Effects of freeze-thaw cycles on sandstone in sunny and shady slopes

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2503-2515页

作者： Dian Xiao Xiaoy.n Zhao Corrado Fidelibus Roberto Tomás qiu Lu Hongwei Liu Academy of Railway Sciences Corporation Limited BeijingChina Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduChina Department of Civil Engineering University of AlicanteAlicanteSpain Department of Innovation Engineering University of SalentoLecceItaly Department of Earth and Environmental Sciences University of Milano BicoccaMilanItaly

A growing rock engineering activity in cold regions is facing the threat of freeze-thaw(FT)weathering,especially in high mountains where the sunny-shady slope effects strongly control the difference in weathering behavior of *** this paper,an investigation of the degradation of petrophysical characteristics of sandstone specimens subjected to FT cycle tests to simulate the sunny-shady slope effects is *** this aim,non-destructive and repeatable testing techniques including weight,ultrasonic waves,and nuclear magnetic resonance methods on standard specimens were *** the sunny slope specimens,accompanied by the enlargement of small pores,100 FT cycles caused a significant decrease in P-wave velocity with an average of 23%,but a consistent rise of 0.18%in mass loss,34%in porosity,67%in pore geometrical mean radius,and a remarkable 14.5-fold increase in ***,slight changes with some abnormal trends in physical parameters of the shady slope specimens were observed during FT cycling,which can be attributed to superficial granular disaggregation and pore throat *** shocks enhance rock weathering on sunny slopes during FT cycles,while FT weathering on shady slopes is restricted to the small pores and the superficial *** two factors are primarily responsible for the differences in FT weathering intensity between sunny and shady *** conclusions derived from the interpretation of the experimental results may provide theoretical guidance for the design of slope-failure prevention measures and the selection of transportation routes in cold mountainous regions.

关键词： Sunny-shady slope Freeze and thaw Pore structure Tight rocks Talus slope Cold regions

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