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Accurate measurements of the bond dissociation energies of^(14)N_(2),^(14N)^(15)N and^(15)N_(2)

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Fundamental Research 2025年第1期5卷 151-157页

作者： Liya Lu Pan Jiang hong Gao Beijing National Laboratory for Molecular sciences(BNLMs) Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of sciences Beijing 100049China

Accurate determinations of bond dissociation energies(BDEs)and the corresponding enthalpies of formation derived from them are of fundamental importance,while on the other hand also very challenging in *** this study,we demonstrate a direct experimental scheme for measuring the BDEs of^(14)N_(2),^(14N)^(15)N and^(15)N_(2)to an accuracy of a few *** high-resolution quantum-state-selected velocity-mapped ion images for several rotational levels with accurately known spectroscopic term energies slightly above the dissociation limit N(^(2)D_(5/2,3/2))+N(^(2)D_(5/2,3/2))were obtained for each of the dinitrogen isotopologue molecules.A linear fit between squares of the radii of the quantum-state-selected images and the spectroscopic term energies gives out an accurate measurement of the threshold D0 for dissociating into the channel N(^(2)D_(5/2,3/2))+N(^(2)D_(5/2,3/2)).The BDEs of^(4)N_(2),^(14N)^(15)N and^(15)N_(2)into the lowest channel N(4s)+N(4s)are independently determined to be 78,688±3,78,705±4 and 78,728±4 cm^(−1),*** independently determined BDEs are found to give a consistent value of De after considering the zero-point energies for each of the isotopologues,implying the reliability of the present *** with several previous measurements and theoretical calculations are *** experimental scheme demonstrated in this study should be generally applicable for precisely determining the BDEs of many other diatomic molecules.

关键词： N_(2) Bond dissociation energy Photodissociation Vacuum ultraviolet Velocity-mapped imaging

Associations between food insecurity with gestational diabetes mellitus and maternal outcomes mediated by dietary diversity:A cross-sectional study

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World Journal of Diabetes 2025年第2期16卷 92-102页

作者： hong-Li Hou Gui-Xia sun Department of Gynecology and Obstetrics Children’s Hospital of ShanxiWomen Health Center of ShanxiTaiyuan 030001Shanxi ProvinceChina

BACKGROUND Food insecurity(Fi)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PiH),resulting in adverse outcomes for both mother and *** To investigate the relationships between Fi and pregnancy outcomes,particularly GDM and PiH,while also examining the mediating role of the dietary diversity score(DDs).METHODs A cross-sectional study was undertaken to examine this relationship,involving 600 pregnant *** were women aged 18 years or older who provided complete data on Fi and pregnancy *** Fi was measured via the Household Food security survey Module,with GDM defined as fasting plasma glucose levels of≥5.1 mmol/L or a 2-hour oral glucose tolerance test value of≥8.5 mmol/*** DDs is determined by evaluating one's food consumption based on nine distinct food groups.A logistic regression model was used to explore the relationship between Fi and PiH,and *** seventeen percent of participants reported experiencing Fi during *** study found a significant association between Fi and an elevated risk of GDM[odds ratio(OR)=3.32,95%Ci:1.2-5.4].Once more,food-insecure pregnant women had higher rates of PiH(OR=0.10,95%Ci:0.02-0.45)and they also faced a higher likelihood of neonatal complications,such as neonatal intensive care unit’s admissions and the birth of infants with extremely low birth *** Fi wasfurther linked to metabolic disruptions,such as elevated fasting blood sugar(FBs),low-density lipoprotein cholesterol,and triglyceride *** results indicate that the DDs acts as a significant mediator in the relationship between Fi and the incidence of *** particular,the mediation analysis showed that approximately 65%of the effect was mediated through DDs(P=0.002).CONCLUsiON These findings underscore the serious challenges that Fi presents during pregnancy and its effects on maternal and infant ***,the study

关键词： Food insecurity Gestational diabetes mellitus Gestational hypertension Pregnancy Maternal health infant health Dietary diversity score

High-temperature calcination dramatically promotes the activity of Cs/Co/Ce-sn catalyst for soot oxidation

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Chinese Chemical Letters 2025年第1期36卷 534-538页

作者： Meng Wang Yan Zhang Yunbo Yu Wenpo shan hong He Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control Ningbo Urban Environment Observation and Research StationInstitute of Urban EnvironmentChinese Academy of SciencesNingbo 315800China state Key Joint Laboratory of Environment simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of sciences Beijing 100049China

Catalytic oxidation of soot is of great importance for emission control on diesel *** this work,a highly active Cs/Co/Ce-sn catalyst was investigated for soot oxidation,and it was unexpectedly found that high-temperature calcination greatly improved the activity of the *** the calcination temperature was increased from 500℃ to 750℃,T_(50) decreased from 456.9℃ to 389.8℃ in a NO/O_(2)/H_(2)O/N_(2) *** results revealed that high-temperature calcination can promote the ability to transfer negative charge density from Cs to other metal cations in Cs/Co/Ce-sn,which will facilitate the production of more oxygen defects and the generation of more surface-active oxygen *** oxygen species are beneficial to the oxidation of NO to NO_(2),leading to the high yield of NO_(2) ***,the Cs/Co/Ce-sn catalyst calcined at 750℃ demonstrated higher activity than that calcined at 500℃.This work provides a pathway to prepare high efficiency catalysts for the removal of soot and significant insight into the effects of calcination on soot oxidation catalysts.

关键词： soot oxidation Calcination surface defects surface-active oxygen species NO_(2)

Radiation belt electron wisp inside south Atlantic Anomaly due to terrestrial VLF transmitter observed by Mss-1

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science China Earth sciences 2025年第2期68卷 538-548页

作者： Yixin sUN Ying LiU Qiugang ZONG Yixin HAO hong ZOU Yuguang YE institute of space Physics and Applied Technology Peking UniversityBeijing 100871China state Key Laboratory of Lunar and Planetary science Macao University of Science and TechnologyMacao 999078China Max Planck institute for solar system Research Goettingen 37077Germany

The south Atlantic Anomaly represents a region within near-Earth space characterized by a significantly weaker geomagnetic field and a higher flux of energetic particles compared to other areas. it is a space weather hazards to Low-EarthOrbit satellites. There has been evidence that the Very Low Frequency(VLF) waves from the powerful ground VLF radio transmitter in Australia, known as NWC, have the capacity to scatter energetic electrons' pitch angle in the inner radiation *** scattering directs electrons into the drift loss cone, forms a “wisp”, characterized by its peak intensity outside the south Atlantic Anomaly(sAA), and a “rift” exhibiting minimal intensity within sAA. Our findings mark the initial observation of a“wisp” precipitation, an unusual occurrence with peak intensity detected inside the sAA, observed via the Macao science satellite-1. Enabled by the Medium-energy Electron spectrometer onboard Macao science satellite-1, we were able to comprehensively measure the full pitch angle distribution at Low-Earth-Orbit. This allowed us to attribute the “wisp” within the anomaly to a specific pitch angle range just outside the drift loss cone, a measurement unattainable by previous satellites. This“wisp” occurrence aligns with previous model predictions, despite being overlooked. Moreover, we distinguished between the trapped and precipitating electron populations. Directly derived from the ratio of these populations, our analysis revealed that approximately 2%-5% of trapped electrons will be lost in this specific wisp due to the influence of the ground VLF *** results not only complement existing evidence of energetic electron pitch angle scattering facilitated by the ground VLF transmitter but also offer a quantitative estimation of its impact.

关键词： south Atlantic Anomaly Radiation belts Electrons precipitation VLF transmitter Wave-particle interaction

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On-line determination of selenium compounds in tea infusion by extractive electrospray ionization mass spectrometry combined with a heating reaction device

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Chinese Chemical Letters 2025年第1期36卷 496-500页

作者： Lu Huang Jiang Wang hong Jiang Lanfang Chen Huanwen Chen Academician Workstation Jiangxi University of Chinese MedicineNanchang 330004China suzhou Jingcheng Precision instrument Technology Co. Ltd.Suzhou 215228China The First Affiliated Hospital of Nanchang University Nanchang 330006China

selenium is one of the important trace elements in the human *** deficiency will directly affect human *** people's attention to health,the content of selenium in food has gradually attracted ***,detecting selenium compounds in complex samples remains a *** this work,we built an online heating-reaction *** device combines the electrospray extraction ionization mass spectrometry(EEsi-Ms)with the heating reaction device,which can simultaneously detect various selenium compounds in complex liquid *** acidic conditions,the sample was heated and catalyzed by a heating reaction device,so that the seO~(2-)_(3)and O-phenylenediamine(OPD)could generate 1,3-dihydro-2,1,*** on the above reactions,we can detect organic selenium,inorganic selenium and other compounds in liquid samples by organic mass *** this experiment,we determined the content of three forms of selenium:selenomethionine(seMet),l-selenocystine(seCys(2)),and sodium *** calibration curves for seMet,seCys(2),and sodium selenite showed strong linearity within a range of 0.50-50.00μg/*** limits of detection(LOD)for the three compounds were 0.22,0.27,and 0.41μg/L,*** limits of quantification(LOQ)were 0.68,0.81,and 1.23μg/L,*** recoveries at three levels ranged from 98.8%to 106.1%.in addition,this method can simultaneously detect three selenium compounds and three other specific chemical components in tea infusion samples,providing a rapid and efficient method for identifying tea quality.

关键词： Heating reaction device Extractive electrospray ionization mass spectrometry inorganic selenium selenium compounds Tea infusion

A Weighted Maximal L_(2) Estimate of Operator-valued Bochner–Riesz Means

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Acta Mathematica sinica,English series 2025年第1期41卷 78-98页

作者： Guixiang hong Liyuan Zhang institute for Advanced study in Mathematics Harbin Institute of TechnologyHarbin 150001P.R.China school of Mathematics and statistics Wuhan UniversityWuhan 430072P.R.China

in this paper,we establish a weighted maximal L_(2) estimate of operator-valued Bochner–Riesz *** proof is based on noncommutative square function estimates and a sharp weighted noncommutative Hardy–Littlewood maxim... 详细信息

关键词： Noncommutative L_(p)-space noncommutative maximal norm Bochner–Riesz means

An online version and some updates of R package *** for standardizing scientific names in plant and animal species

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Plant Diversity 2025年第1期47卷 166-168页

作者： Jian Zhang hong Qian Xinyang Wang school of Life sciences Sun Yat-Sen UniversityGuangzhou 510275China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA school of Ecological and Environmental sciences East China Normal UniversityShanghai 200241China

We are now in the era of big data for biodiversity *** and larger datasets on species geographic distributions,community composition,and functional traits are now becoming more increasingly than ever *** applying taxo... 详细信息

关键词： Biodiversity informatics species name matching Taxonomic harmonization Taxonomic tool U.Taxonstand

Modeling net-charge fluctuations in heavy-ion collisions at the LHC

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Chinese Physics C 2025年第1期49卷 281-289页

作者： G.O.Ambaryan A.s.Chernyshov G.Kh.Eyyubova V.L.Korotkikh i.P.Lokhtin s.V.Petrushanko A.M.snigirev E.E.Zabrodin Physics Department Lomonosov Moscow State UniversityRU-119991 MoscowRussia skobeltsyn institute of Nuclear Physics Lomonosov Moscow State UniversityRU-119991 MoscowRussia Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear ResearchRU-141980 DubnaRussia Department of Physics University of OsloN-0316 OsloNorway

Analysis of Pb+Pb data for net-charge fluctuations at LHC energies using the HYDJET++model is *** strongly intensive quantities D and Σ were used to remove the effects related to system volume *** employed two versions of HYDJET++for the *** first one is the standard or default version,whereas the second one is a modification that takes into account explicit event-by-event conservation of the electric net-charge of produced *** inclusion of the canonical net-charge conservation in the model allows for better description of the experimental data obtained by the ALiCE and CMs Collaborations.A comparison with calculations from other models is also presented.

关键词： relativistic heavy-ion collisions net-charge fluctuations strongly intensive variables canonical charge conservation

New classification of gastric polyps:An in-depth analysis and critical evaluation

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World Journal of Gastroenterology 2025年第7期31卷 149-155页

作者： Xiao-Hui Liao Ying-Ming sun hong-Bin Chen Department of Gastroenterology The First Hospital of Sanming Affiliated to Fujian Medical UniversityFujian Medical UniversitySanming 365000Fujian ProvinceChina Department of Medical and Radiation Oncology Sanming First HospitalFujian Medical UniversitySanming 365000Fujian ProvinceChina Department of Gastroenterology i Sanming First HospitalFujian Medical UniversitySanming 365000Fujian ProvinceChina

With the widespread use of upper gastrointestinal endoscopy,more and more gastric polyps(GPs)are being *** management strategies often rely on histopathologic examination,which can be time-consuming and may not guide immediate clinical *** paper aims to introduce a novel classification system for GPs based on their potential risk of malignant transformation,categorizing them as"good","bad",and"ugly".A review of the literature and clinical case analysis were conducted to explore the clinical implications,management strategies,and the system's application in endoscopic *** polyps,mainly including fundic gland polyps and inflammatory fibrous polyps,have a low risk of malignancy and typically require minimal or no *** polyps,mainly including hyperplastic polyps and adenomas,pose an intermediate risk of malignancy,necessitating closer monitoring or *** polyps,mainly including type 3 neuroendocrine tumors and early gastric cancer,indicate a high potential for malignancy and require urgent and comprehensive *** new classification system provides a simplified and practical framework for diagnosing and managing GPs,improving diagnostic accuracy,guiding individualized treatment,and promoting advancements in endoscopic *** some challenges,such as the risk of misclassification due to similar endoscopic appearances,this system is essential for the standardized management of *** also lays the foundation for future research into biomarkers and the development of personalized medicine.

关键词： Gastric polyps Classification Fundic gland polyps inflammatory fibroid polyps Hyperplastic polyps Adenomas Neuroendocrine tumors Early gastric cancer Patient management