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Kinetics of the reaction of OH radical with ethylfluoroacetate,ethyl 4,4,4-trifluorobutyrate,and butylfluoroacetate

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Journal of Environmental Sciences 2025年第5期151卷 273-283页

作者： Pedro l.lugo Vianni Straccia Mariano A.Teruel María B.Blanco laboratorio Universitario de Química y Contaminación del Aire(l.U.Q.C.A) Institute for Research in Physical Chemistry of Córdoba(I.N.F.I.Q.C.)Department of Physical ChemistryFaculty of Chemical SciencesNational University of CórdobaUniversity CityCórdoba 5000Argentina Institute for Atmospheric and Environmental Research University of WuppertalWuppertal DE-42097Germany

Kinetics of the gas-phase reactions of•OH radicals with a series of fluoroesters were studied for the first time at 298±3 K and atmospheric *** rate coefficients were determined by in situ FTIR spectroscopy in nitrogen and GC-FID in air to monitor the decay of reactants and *** following coefficient values(in 10^(−12)cm^(3)/(molecule•sec))were obtained for ethyl fluoroacetate(EFA),ethyl 4,4,4-trifluorobutyrate(ETB),and butyl fluoroacetate(BFA),respectively:k_(1)(EFA+OH)=1.15±0.25 by FTIR and 1.34±0.23 by GC-FID;k_(2)(ETB+OH)=1.61±0.36 by FTIR and 2.02±0.30 by GC-FID;k_(3)(BFA+OH)=2.24±0.37 by *** trends were developed and correlated with the number of CH_(3)and F substituents in the fluoroester,and structure-activity relationships(SARs)calculations were *** addition,the tropospheric lifetimes of EFA,ETB,and BFA upon degradation by OH radicals were calculated to be 9,6,and 5 days,respectively,indicating that these fluorinated compounds could have a possible regional effect from the emission *** small photochemical ozone creation potentials of 9,7,and 19 were estimated for EFA,ETB,and BFA,*** GlobalWarming Potentials(GWPs)for EFA,ETB,and BFA were calculated for different time *** a 20-year time horizon,the GWPs were 1.393,0.063,and 0.062,*** the case of a 100-year time horizon,the GWPs were 0.379,0.017,and 0.017,and for a 500-year time horizon,the GWPs were 0.108,0.005,and 0.005 for EFA,ETB,and BFA.

关键词： CFC replacements sinks in situ FTIR SAR Acidification potentials Greenhouse gases

Abrasive wear behavior of functionally graded Al_(3)Ti reinforced aluminum matrix composite

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China Foundry 2025年第1期22卷 45-54页

作者： Eylül Tuğçe Yaman Yildiz Ömer Savaş Muhammed Soner Başer Engin Kocaman Ince Shipping Group 34724IstanbulTurkey Yildiz Technical University Faculty of Naval Architecture and Maritime34349IstanbulTurkey Ministry of Transport and Infrastructure General Directorate of Marine Affairs06338AnkaraTurkey Zonguldak Bulent Ecevit University Faculty of EngineeringDepartment of Aerospace Engineering67100ZonguldakTurkey

Aluminum alloys are widely used in industry due to their light *** alloys are generally exposed to abrasive wear,which diminishes their effective *** wear resistance of these alloys is enhanced by adding various reinforcements,however,this enhancement comes at the cost of reduced fracture *** paradox of increased wear resistance versus decreased fracture toughness in aluminum alloys can be resolved by using functionally graded materials (FGMs).This study focuses on the abrasive wear behavior of functional graded aluminum matrix composites reinforced with Al_(3)Ti *** wear properties of the composites were investigated by considering the characteristics of the composite such as matrix type and various composite zones,as well as the wear parameters such as abrasive particle diameter,load,sliding speed and *** method was used in the abrasive wear tests in order to get more reliable results in a timeefficient *** recipes were created based on the l_(27)(3^(6)) orthogonal *** a result of the study,it is observed that the wear resistance of the composites increases with an increase in Al_(3)Ti reinforcement content and hardness of the *** addition,the size of abrasive particles and the applied load are significant factors affecting abrasive wear.

关键词： functionally graded Al_(3)Ti Taguchi abrasive wear

Analysis of the redox environment and genesis of surface sediment in the northeast Indian Ocean at the Ninety-East Ridge

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Journal of Oceanology and limnology 2025年第1期43卷 57-72页

作者： Zhourong CAI Qianru HUANG Zhengxin YIN xin SUI Sibo lÜ Meng TANG Juan PENG School of Marine Sciences Sun Yat-sen UniversityZhuhai 519082China Guangdong Provincial Key laboratory of Marine Resources and Coastal Engineering Zhuhai 519082China South China Sea Marine Survey Center Ministry of Natural ResourcesGuangzhou 510275China Key laboratory of Marine Environmental Survey Technology and Application Ministry of Natural ResourcesGuangzhou 510275China

The Ninety-East Ridge(NER)is located in the semioceanic to oceanic region of the southern Bengal Fan in the Northeast Indian *** sedimentary environment,ocean currents,and scientific issues related to climate change have always been the focus of *** well understand the sedimentary environment of the sea area,we studied the modern sedimentary environment of the NER by analyzing the redox-sensitive trace elements(RSEs)and biomarkers in the surface sediments of the northern region and both sides of the NER and the mechanism of their *** ratios of Mo/U(average 2.22),(Cu+Mo)/Zn(average 1.51),and the results ofδCeles,all indicate the reduction of the sedimentary *** addition,the ratio of pristane(Pr)to phytane(Ph),C30diahopane to C30 hopane,and diasterane to sterane were low in all samples,on average of 1.03,0.9,and 0.33,*** analysis of RSE and biomarker data revealed that the sedimentary environment on seabed of the NER is generally a rare low-oxygen reduction *** the analysis of sediment characteristics,material sources,and ocean currents,we preliminarily constructed a genetic model for the low-oxygen reducing environment of surface sediments in the *** believe that the low-oxygen reduction environment of surface sediment in the NER could be influenced by multiple factors,such as terrestrial input of materials,productivity at sea surface,and sediment particle size.

关键词： Ninety-East Ridge(NER) surface sediment sedimentary environment redox-sensitive trace elements(RSEs) biomarker

Non-existence of Shimura curves of Mumford type generically in the non-hyperelliptic locus

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Science China Mathematics 2025年

作者： xin lü Shengli Tan Kang Zuo School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications(Ministry of Education) Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal University School of Mathematics and Statistics Wuhan University Institut für Mathematik Universit?t Mainz

We show that there does not exist any Shimura curve with a strictly maximal Higgs field generically in the Torelli locus of non-hyperelliptic curves of genus g≥4. In particular, Shimura curves of Mumford type are not...

关键词：

ECHOS OF THE STEINER-lEHMUS EQUAl BISECTORSSTHEOREM

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Acta Mathematica Scientia 2025年第1期45卷 257-263页

作者： Christoph BÖRGERS Eric l.GRINBERG Mehmet ORHON Junhao SHEN Department of Mathematics Tufts UniversityMedfordMA02155USA Department of Mathematics University of Massachusetts BostonBostonMA02125USA Department of Mathematics&Statistics University of New HampshireDurhamNH03824USA

The Steiner-lehmus equal bisectors theorem originated in the mid 19th *** its age,it would have been accessible to Euclid and his *** theorem remains evergreen,with new proofs continuing to appear *** theorem has fostered discussion about the nature of proof itself,direct and *** we continue the momentum by providing a trigonometric proof,relatively short,based on an analytic estimate that leverages algebraic trigonometric *** proofs of the theorem exist in the *** of these contain key ideas that already appeared in ***’1850 proofs,not always with *** the aim of increasing awareness of and making more accessible lehmus’proofs,we provide an annotated *** conclude with remarks on different proofs and relations among them.

关键词： Steiner-lehmus theorem equal bisectors

Rapid detection of colored and colorless macroand micro-plastics in complex environment via near-infrared spectroscopy and machine learning

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Journal of Environmental Sciences 2025年第1期147卷 512-522页

作者： Hui-Huang Zou Pin-Jing He Wei Peng Dong-Ying lan Hao-Yang xian Fan lü Hua Zhang Institute of Waste Treatment&Reclamation College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

To better understand the migration behavior of plastic fragments in the environment,development of rapid non-destructive methods for in-situ identification and characterization of plastic fragments is ***,most of the studies had focused only on colored plastic fragments,ignoring colorless plastic fragments and the effects of different environmental media(backgrounds),thus underestimating their *** address this issue,the present study used near-infrared spectroscopy to compare the identification of colored and colorless plastic fragments based on partial least squares-discriminant analysis(PlS-DA),extreme gradient boost,support vector machine and random forest *** effects of polymer color,type,thickness,and background on the plastic fragments classification were ***-DA presented the best and most stable outcome,with higher robustness and lower misclassification *** models frequently misinterpreted colorless plastic fragments and its background when the fragment thickness was less than 0.1mm.A two-stage modeling method,which first distinguishes the plastic types and then identifies colorless plastic fragments that had been misclassified as background,was *** method presented an accuracy higher than 99%in different *** summary,this study developed a novel method for rapid and synchronous identification of colored and colorless plastic fragments under complex environmental backgrounds.

关键词： Colorless microplastics Near-infrared hyperspectral imaging Plastic identification Partial least squares discriminant analysis Machine learning

Human health risks associated to trace elements and metals in commercial fish from the Brazilian Amazon

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Journal of Environmental Sciences 2025年第2期148卷 230-242页

作者： Andrea V.Waichman Gabriel Silva de Souza Nunes Rhaul de Oliveira Isabel lópez-Heras Andreu Rico Federal University of the Amazon Institute of Biological SciencesAv.Rodrigo Ramos 3000Manaus 69077-000Brazil Federal University of Pernambuco Department of ZoologyAv.Prof Moraes Rego 1235Cidade UniversitáriaRecife 50670-901Brazil University of Campinas School of TechnologyRua Paschoal Marmo 1888-Jd.Nova ItáliaLimeira 13484-332Brazil IMDEA Water Institute Science and Technology Campus of the University of AlcaláAv.Punto Com 2Alcaláde Henares 28805MadridSpain Cavanilles Institute of Biodiversity and Evolutionary Biology University of Valenciac/Catedrático JoséBeltrán 246980PaternaValenciaSpain

Fish constitutes the main protein source for the Amazonian ***,the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely *** we assessed exposure levels of 10 trace elements andmetals(Cr,Mn,Fe,Ni,Cu,Zn,As,Cd,Pb,and Hg)in 56 samples belonging to 11 different species of fish from the Brazilian *** studied the relationship between exposure levels,fish origin,and fish feeding habits,and assessed toxicological and carcinogenic risks for the Amazonian *** significant correlation was found between sampling site and exposure levels to the studied elements,but a significant difference was found between the accumulation of some metals and the position of the fish species in the food *** concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human *** study shows that current fish consumption patterns can lead to estimated daily intakes of Hg,As and Cr that exceed the oral reference dose,thus posing a toxicological ***,carcinogenic risks may be expected due to the continued exposure to Cr and *** results of this study show that the consumption of wild caught fish in the Amazon region should be ***,continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended,particularly for riverine and indigenous communities.

关键词： Metals Deforestation Mining Freshwater ecosystems Carcinogenic risks Amazon

Prehospital critical care drug-therapy and 30-day mortality in patients with acute respiratory disease

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World Journal of Emergency Medicine 2025年第1期16卷 43-50页

作者： Jesús Jurado-Palomo Joséluis Martín-Conty Begoña Polonio-lópez Cristina Rivera Picón Raúl lópez-Izquierdo Carlos del Pozo Vegas Pedro Ángel de Santos Castro Ancor Sanz-García Francisco Martín-Rodríguez Technological Innovation Applied to Health Research Group(ITAS) Faculty of Health SciencesCastilla-La Mancha UniversityTalavera de la Reina 45600Spain Nuestra Señora del Prado General Hospital Talavera de la Reina 45600Spain Emergency Department Rio Hortega University HospitalValladolid 47012Spain CIBER of Respiratory Diseases(CIBERES) Institute of Health Carlos ⅢMadrid 28029Spain Faculty of Medicine University of ValladolidValladolid 470003Spain Emergency Department University Clinical HospitalValladolid 47003Spain Prehospital Emergency Medical Services(SACYl) Valladolid 47007Spain

BACKGROUND: Prehospital medication is a reality, and the role of these therapies must be explored to assess their validity, especially for acute respiratory diseases, which are usually associated with increased morbidity. The aim of this study was to examine the association of prehospital medication use with mortality in patients with acute respiratory ***: A prospective, multicenter, emergency medical service(EMS) delivery cohort study was carried out in adults with unselected respiratory diseases managed by EMS who were transferred to the emergency department. From January 1, 2019, to October 31, 2023, six advanced life support units, thirty-eight basic life support units, and four hospitals in Spain participated in the study. Demographic data, vital signs, use of mechanical ventilation, prehospital respiratory diagnosis, and prehospital medication were collected. The primary outcome was 30-day in-hospital ***: A total of 961 patients were included, with a mortality rate of 17.5%(168 patients). Age, an increasing number of comorbidities, the use of invasive mechanical ventilation(IMV), the use of major analgesics, hypnotics, and bicarbonate were risk factors. In contrast, elevated systolic blood pressure and Glasgow Coma Scale scores were found to be protective factors against mortality. The predictive capacity of the model reached an area under the curve(AUC) of 0.857(95% confidence interval [95% CI] 0.827–0.888).CONClUSION: Our data revealed that IMV, major analgesics, hypnotics and bicarbonate administration were associated with elevated mortality. Adding prehospital drug therapy information to demographic variables and vital signs could improve EMS decision-making, allowing a better characterization of patients at risk of clinical worsening.

关键词： Drug-therapy Medication Prehospital Mortality Emergency medical services

Risk factors, prevention and screening of colorectal cancer: A rising problem

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World Journal of Gastroenterology 2025年第5期31卷 117-123页

作者： Vladislav V Tsukanov Alexander V Vasyutin Julia l Tonkikh Clinical Department of The Digestive System Pathology of Adults and Children Federal Research Center“Krasnoyarsk Science Center”of the Siberian Branch of the Russian Academy of SciencesScientific Research Institute of Medical Problems of the NorthKrasnoyarsk 660022Russia

Colorectal cancer(CRC)is the third most commonly diagnosed cancer and the second leading cause of cancer death *** leading risk factors for CRC include male gender,age over 50,family history,obesity,tobacco smoking,alco-hol consumption,and unhealthy *** screening methods vary considerably between countries and depend on incidence,economic resources and healthcare *** aspects of screening include adherence,which can vary signi-ficantly across ethnic and socioeconomic *** concepts of CRC screening include pre-stratification of patients by identifying risk factors and then using fecal immunochemical test or guaiac-based fecal occult blood test and/or colono-scopy or radiologic imaging *** capabilities for CRC scree-ning are rapidly evolving and include stool DNA test,liquid biopsy,virtual colo-nography,and the use of artificial intelligence.A CRC prevention strategy should be comprehensive and include active patient education along with targeted imple-mentation of screening.

关键词： Colorectal cancer Screening Prevention Risk factors Colonoscopy Fecal immunochemical test Fecal occult blood test Stool DNA test Diet lynch syndrome