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Atmospheric chemistry of.trif.uorodicarbonyls initiated by Cl atoms:Reactivity trends,mechanism,and acid f.rmation yields

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Journal of.Environmental Sciences 2025年第5期151卷 12-25页

作者： Pedro l.lugo Vianni G.Straccia Cynthia B.Rivela Mariano A.Teruel María B.Blanco laboratorio Universitario de Química y Contaminación del Aire(l.U.Q.C.A) Instituto de Investigaciones en Fisicoquímica de Córdoba(I.N.F.I.Q.C.)Dpto.de Fisicoquímica.Facultad de Ciencias QuímicasUniversidad Nacional de Córdoba.Ciudad Universitaria5000 CórdobaArgentina Institute f.r Atmospheric and Environmental Research University of WuppertalDE-42097 WuppertalGermany

Rate coef.icients of.the gas-phase reactions of.Cl atoms with a series of.f.uorinated diketones(f.Ks):Cf.(3)C(O)CH_(2)C(O)CH_(3)(Tf.),Cf.(3)C(O)CH_(2)C(O)CH_(2)CH_(3)(Tf.)and Cf.(3)C(O)CH_(2)C(O)CH(CH_(3))2(Tf.H),have been measured at(298±2)K and under atmospheric *** experiments were perf.rmed using the relative-rate method with a GC-f.D detection *** dif.erent determinations and ref.rences used,the f.llowing rate coef.icients were obtained(in cm3/(molecule·sec)):k_(4)(Tf.+Cl)=(1.75±0.21)×10^(−10),k_(5)(Tf.+Cl)=(2.05±0.23)×10^(−10),k_(6)(Tf.H+Cl)=(2.71±0.34)×10^(−10).Reactivity trends of.f.Ks were discussed and f.ee Energy Relationships analysis was *** expression lgkOH=1.68 lgkCl+5.71 was obtained f.r the reactivity of.the studied f.Ks together with similar unsaturated VOCs with Cl and OH radicals Additionally,acetic acid(CH_(3)C(O)OH)and trif.uoroacetic acid(Cf.(3)C(O)OH)were positively identif.ed and quantif.ed as degradation products using in situ f.IR *** to the identif.ed products,atmospheric chemical mechanisms were *** atmospheric implications of.the studied reactions were assessed by the estimation of.the tropospheric lif.times of.Tf.,Tf.,and Tf.H concerning their reaction with Cl atoms to be 48,41,and 31 hours,*** relatively short residence in the atmosphere of.the f.uorocarbons studied will have a local/regional impact with restricted *** warming potential(GWP(20 yr))calculated f.r the studied f.uoro diketones were 0.014,0.003 and 0.001 f.r Tf.,Tf. and Tf.H,respectively with a negligible contribution to the greenhouse ef.ect.

关键词： f.uorinated diketones Kinetics SPME-GC-f.D f.IR in situ SAR f.ee energy relationships

Promotion of.structural plasticity in area V2 of.visual cortex prevents against object recognition memory def.cits in aging and alzheimer's disease rodents

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Neural Regeneration Research 2024年第8期19卷 1835-1841页

作者： Irene Navarro-lobato Mariam Masmudi-Martín Manuel f.l.pez-Aranda Juan f.l.pez-Téllez Gloria Delgado Pablo Granados-Durán Celia Gaona-Romero Marta Carretero-Rey Sinf.riano Posadas María E.Quiros-Ortega Zaf.r U.Khan laboratory of.Neurobiology Centro de Investigaciones Médico Sanitarias(CIMES)University of MalagaMalagaSpain Department of.Medicine Faculty of MedicineUniversity of MalagaMalagaSpain Centro de Investigación Biomédica en Red de Enf.rmedades Neurodegenerativas(CIBERNED) Institute of Health Carlos IIIMadridSpain the Donders Institute f.r Brain Cognition and Behaviour Radboud UniversityNijmegenThe Netherlands the Brain Metastasis Group National Cancer Research Centre(CNIO)MadridSpain the Department of.Neurobiology University of California-Los AngelesLos AngelesCAUSA

Memory def.cit,which is of.en associated with aging and many psychiatric,neurological,and neurodegenerative diseases,has been a challenging issue f.r *** till now,all potential drug candidates have f.iled to produce satisf. ctory ***,in the search f.r a solution,we f.und that a treatment with the gene corresponding to the RGS14414protein in visual area V2,a brain area connected with brain circuits of.the ventral stream and the medial temporal lobe,which is crucial f.r object recognition memory(ORM),can induce enhancement of.*** this study,we demonstrated that the same treatment with RGS14414in visual area V2,which is relatively unaf.ected in neurodegenerative diseases such as alzheimer s disease,produced longlasting enhancement of.ORM in young animals and prevent ORM def.cits in rodent models of.aging and alzheimer’s ***,we f.und that the prevention of.memory def.cits was mediated through the upregulation of.neuronal arbo rization and spine density,as well as an increase in brain-derived neurotrophic f.ctor(BDNf..A knockdown of.BDNf.gene in RGS14414-treated aging rats and alzheimer s disease model mice caused complete loss in the upregulation of.neuronal structural plasticity and in the prevention of.ORM *** f.ndings suggest that BDNf.mediated neuronal structural plasticity in area V2 is crucial in the prevention of.memory def.cits in RGS14414-treated rodent models of.aging and alzheimer’s ***,our f.ndings of.RGS14414gene-mediated activation of.neuronal circuits in visual area V2 have therapeutic relevance in the treatment of.memory def.cits.

关键词： behavioral perf.rmance brain-derived neurotrophic f.ctor cognitive dysf.nction episodic memory memory circuit activation memory def.cits memory enhancement object recognition memory prevention of.memory loss regulator of.G protein signaling

l-shell x-ray f.uorescence relative intensities f.r elements with 62≤Z≤83 at 18 keV and 23 keV by synchrotron radiation

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Chinese Physics B 2023年第8期32卷 270-273页

作者： M alqadi S al-Humaidi H alkhateeb f.alzoubi Department of.Physics Jordan University of Science and TechnologyIrbidJordan

The relative intensities of.l-subshell x-ray f.uorescence(XRf.f.r elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of.the Synchrotron light Center f.r Experimental Science and Applications in the Middle East(SESAME),*** experimentally measured results of.the relative intensities were compared with the calculated results using the subshell f.uorescence yield and the Coster-Kronig transition probabilities recommended by Campbell and the values based on the Dirac-Hartree-Slater model by *** experimental and theoretical results are in *** this work,l XRf.relative intensities f.r the elements Sm,Gd,Tb,Er,Ta,W,Re,Hg,Pb and Bi at energies of.18 keV and 23 keV were measured.

关键词： l shell x-ray f.uorescence(XRf. relative intensities synchrotron radiation

lethal toxicity of.industrial detergent on bottom dwelling sentinels

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International Journal of.Sediment Research 2009年第4期24卷 479-483页

作者： l. I. N. EZEMONYE D. f. OGElEKA f. E. OKIEIMEN Department of.Animal and Environmental Biology (AEB) University of Benin Department of.Chemistry University of Benin

We used f.esh and brackish water shrimp (Desmoscaris trispinosa and Palaemonetes af.icanus), in sediment bioassays to assess the toxicity of.an industrial detergent containing high levels of.anionic surf.ctant (linear alkylbenzene sulphonate (lAS)). The Organization f.r Economic Cooperation and Development (OECD), # 218 direct sediment toxicity assessment was employed. The organisms were exposed to dif.erent concentrations (31.25, 62.5, 125, 250 and 500 mg/kg) of.the chemical (Neatex) in replicate treatments. Percentage mortality was measured as the ecological endpoint. Mean mortality and estimated lethal concentration lC 50 values varied with species type, concentration and exposure duration. The statistical variation in the observed mean mortality of.the test organisms in the chemical and the control treatment shows that mortality may be induced by the ef.ect of.the chemicals. The lethal concentration (lC 50 ) was signif.cantly dif.erent at levels of.p f.r the f.esh and brackish water experiments. Consequently, assessment of.water and sediment quality as a result of.chemical pollutants was necessary f.r protecting some of.the more sensitive benthic invertebrates representing the major proportion of.the diet of.many species in the Niger Delta ecological zone.

关键词： Arthropod (shrimp) Desmoscaris trispinosa Palaemonetes af.icanus Mortality Sediment Chemicals

The 2.7 K black-body radiation background ref.rence f.ame

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Chinese Physics B 2010年第4期19卷 16-20页

作者： l.pez-Carrera Benjamín Rosales Marco Antonio Ares de Parga Gonzalo Departamento de f.sica Escuela Superior de Física y MatemticasInstituto Politécnico NacionalU.P.A.López MateosZacatenco 07738México DFMéxico Departamento de f.sica Universidad de las AméricasSanta Catarina MrtirC.P.72820CholulaPuebla.México

This paper reports that the directional temperature is used to present a scheme f.r deducing the velocity of.the ref.rence f.ame where the black-body which produces the 2.7 K radiation background is at rest. The new r... 详细信息

关键词： relativistic transf.rmations thermodynamics covariance black-body radiation

Changes in nectar supply： A possible cause of.widespread butterf.y decline

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Current Zoology 2012年第3期58卷 384-391页

作者： Michiel f. WallISDEVRIES Chris A.M. Van SWAAY Calijn l. PlATE De Vlinderstichting / Dutch Butterf.y Conservation EO. Box 506 6700 AM Wageningen The Netherlands Wageningen University Lab of Entomology EO. Box 8031 6700 EH Wageningen The Netherlands Statistics Netherlands （CBS） P.O. Box 24500 2490 HA The Hague The Netherlands

Recent studies have documented declining trends of.various groups of.f.ower-visiting insects, even common butterf.y species. Causes of.these declines are still unclear but the loss of.habitat quality across the wider countryside is thought to be a major f.ctor. Nectar supply constitutes one of.the main resources determining habitat quality. Yet, data on changes in nectar abundance are lacking. In this study, we provide the f.rst analysis of.changes in f.oral nectar abundance on a national scale and link these data to trends in butterf.y species richness and abundance. We used transect data f.om the Dutch Butterf.y Monitoring Scheme to compare two time periods： 1994-1995 and 2007-2008. The results show that butterf.y decline can indeed be linked to a substantial decline in overall f.ower abundance and specif.c nectar plants, such as thistles. The decline is as severe in reported f.ower generalists as in f.ower specialists. We suggest that eutrophication is a main cause of.the decline of.nectar sources [Current Zoology 58 （3）： 384-391, 2012].

关键词： Butterf.ies Eutrophication Habitat quality land use Nectar resources Pollinators

A STUDY ON MICRO-PlASTIC DEf.RMATION BEHAVIOR Of.2024 A1 allOY

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Acta Metallurgica Sinica(English letters) 2000年第2期13卷 502-507页

作者： f. Yang C. H. Wu D. l. Sun School of.Materials Science & Engineering Harbin Institute of Technology Harbin 150001 China

Dimensional stability properties of.hot extruded 2024 al alloy bar in T4 and T6 aging states and dif. f.rent extruded directions were investigated by testing micro-yield strength (MYS), stress relaxation resistance (SRR), and dimensional change in thermal cycling and unloading *** results show that micro-plastic def.rmation resistance in longitudinal(parallel to the axis of.the extruded bar) direction is higher than that in transverse(perpendicular to the axis of.the extruded bar) direction. Testing in short-term loading condition MYS value corresponding to micro-plastic strain of.1 *10m^(-5)in longitudinal direction is 1.4 times than that in *** with the results of.MYS and dimensional change in thermal cycling and unloading conditions, the values in T6 state are higher than that in T4 state. Using TEM the microstructures bef.re micro-plastic def.rmation were *** analyses conf.rm that stability of.thermodynamics condition and dislocation results in dimensional stability of.the alloy.

关键词： 2024 al alloy dimensional stability aging micro-yield strength stress relaxation

STUDY ON HOT SAND COOlING EQUIPMENT WITH DAMPING SAND CASCADE AND VERTICal SPOUTED-f.UIDIZED BED

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Acta Metallurgica Sinica(English letters) 2005年第5期18卷 669-673页

作者： l. C. Wang f. Wang X.H. You Department of.Material Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China

A new kind of.hot sand cooling equipment with vertical spouted-f.uidized bed is developed in this paper. It is similar to the traditional horizontal vibrating f.uidized boiling cooler in principle but dif.erent f.om it in structure. The processing principle of.the cooler is analyzed. The inf.uence of.main structural and processing parameters on the cooling ef.ect and its mechanism are researched. Other characteristics of.the cooler are discussed also. Experiment results show that the cooling ef.iciency η is equal to or larger than 83%, the temperature of.output sand is less than 40℃ with the temperature of.input sand is about between 80 and 90℃, and the productivity is 5t/ （h·m）

关键词： hot sand cooling f.uidized bed f.undry equipment

CORBA-Based Discrete Event Simulation System

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Journal of.Systems Engineering and Electronics 2001年第3期12卷 16-19页

作者： luo, J. Zheng, S. Zhong, l. Duan, f. Neocomputer Research Xi'an Jiaotong University Xi'an 710049 China

The CORBA technique is an integration of.the object-oriented conception and distributed computing technique. It can make the application within distributed heterogeneous environments reusable, portable and interoperable. The architecture of.CORBA-based discrete event simulation systems is presented and the interf.ce of.distributed simulation objects (DSO) is def.ned in this paper af.er the DSO is identif.ed and the synchronization mechanism among DSO is discussed.

关键词： Computational methods Computer architecture Computer simulation Computer sof.ware portability Computer sof.ware reusability Interf.ces (computer) Interoperability Object oriented programming Synchronization