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Atmospheric chemistry of trifluorodicarbonyls initiated by Cl atoms:Reactivity trends,mechanism,and acid formation 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 for Atmospheric and Environmental Research University of WuppertalDE-42097 WuppertalGermany

Rate coefficients of the gas-phase reactions of Cl atoms with a series of fluorinated diketones(FDKs):CF_(3)C(O)CH_(2)C(O)CH_(3)(TFP),CF_(3)C(O)CH_(2)C(O)CH_(2)CH_(3)(TFH)and CF_(3)C(O)CH_(2)C(O)CH(CH_(3))2(TFMH),have been measured at(298±2)K and under atmospheric *** experiments were performed using the relative-rate method with a GC-FID detection *** different determinations and references used,the following rate coefficients were obtained(in cm3/(molecule·sec)):k_(4)(TFP+Cl)=(1.75±0.21)×10^(−10),k_(5)(TFH+Cl)=(2.05±0.23)×10^(−10),k_(6)(TFMH+Cl)=(2.71±0.34)×10^(−10).Reactivity trends of FDKs were discussed and Free Energy Relationships analysis was *** expression lgkOH=1.68 lgkCl+5.71 was obtained for the reactivity of the studied FDKs together with similar unsaturated VOCs with Cl and OH radicals Additionally,acetic acid(CH_(3)C(O)OH)and trifluoroacetic acid(CF_(3)C(O)OH)were positively identified and quantified as degradation products using in situ FTIR *** to the identified products,atmospheric chemical mechanisms were *** atmospheric implications of the studied reactions were assessed by the estimation of the tropospheric lifetimes of TFP,TFH,and TFMH concerning their reaction with Cl atoms to be 48,41,and 31 hours,*** relatively short residence in the atmosphere of the fluorocarbons studied will have a local/regional impact with restricted *** warming potential(GWP(20 yr))calculated for the studied fluoro diketones were 0.014,0.003 and 0.001 for TFP,TFH and TFMH,respectively with a negligible contribution to the greenhouse effect.

关键词： Fluorinated diketones Kinetics SPME-GC-FID FTIR in situ SAR Free energy relationships

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

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

A C-type lectin with dual carbohydrate recognition domains functions in innate immune response in Asian corn borer, Ostrinia furnacalis

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INSECT SCIENCE 2025年第1期32卷 172-192页

作者： li, Er-Tao Ji, Jia-Yue kong, Wei-Jie Shen, Dong-Xu li, Cai An, Chun-Ju China Agr Univ Coll Plant Protect Dept Entomol Beijing 100193 Peoples R China Shanxi Agr Univ Pomol Inst Jinzhong Shanxi Peoples R China Jiangsu Univ Sci & Technol Sch Biotechnol Jiangsu Key Lab Sericultural Biol & Biotechnol Zhenjiang Jiangsu Peoples R China

C-type lectins (CTls) act as pattern recognition receptors (PRRs) to initiate the innate immune response in insects. A CTl with dual carbohydrate recognition domains (CRDs) (named immulectin-4 [IMl-4]) was selected from the Ostrinia furnacalis transcriptome dataset for functional studies. We cloned the full-length complementary DNA of O. furnacalis IMl-4 (OfIMl-4). It encodes a 328-residue protein with a Glu-Pro-Asn (EPN) and Gln-Pro-Asp (QPD) motifs in 2 CRDs, respectively. OfIMl-4 messenger RNA levels increased significantly upon the bacterial and fungal infection. Recombinant OfIMl-4 (rIMl-4) and its individual CRDs (rCRD1 and rCRD2) exhibited the binding ability to various microorganisms including Escherichia coli, Micrococcus luteus, Pichia pastoris, and beauveria bassiana, and the cell wall components including lipopolysaccharide from E. coli, peptidoglycan from M. luteus or bacillus subtilis, and curdlan from Alcaligenes faecalis. The binding further induced the agglutination of E. coli, M. luteus, and b. bassiana in the presence of calcium, the phagocytosis of Staphylococcus aureus by the hemocytes, in vitro encapsulation and melanization of nickel-nitrilotriacetic acid beads, and a significant increase in phenoloxidase activity of plasma. In addition, rIMl-4 significantly enhanced the phagocytosis, nodulation, and resistance of O. furnacalis to b. bassiana. Taken together, our results suggest that OfIMl-4 potentially works as a PRR to recognize the invading microorganisms, and functions in the innate immune response in O. furnacalis.

关键词： cellular immunity C-type lectin humoral immunity immulectin Ostrinia furnacalis pattern recognition receptor (PRR)

Support effect and confinement effect of porous carbon loaded tin dioxide nanoparticles in high-performance CO_(2) electroreduction towards formate

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Chinese Chemical letters 2025年第1期36卷 597-602页

作者： Xingxing Jiang Yuxin Zhao Yan kong Jianju Sun Shangzhao Feng Xin lu Qi Hu Hengpan Yang Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

leveraging the interplay between the metal component and the supporting material represents a cornerstone strategy for augmenting electrocatalytic efficiency,e.g.,electrocatalytic CO_(2)reduction reaction(CO_(2)RR).Herein,we employ freestanding porous carbon fibers(PCNF)as an efficacious and stable support for the uniformly distributed SnO_(2)nanoparticles(SnO_(2)PCNF),thereby capitalizing on the synergistic support effect that arises from their strong *** one hand,the interaction between the SnO_(2)nanoparticles and the carbon support optimizes the electronic configuration of the active *** interaction leads to a noteworthy shift of the d-band center toward stronger intermediate adsorption energy,consequently lowering the energy barrier associated with CO_(2)*** a result,the Sn O_(2)PCNF realizes a remarkable CO_(2)RR performance with excellent selectivity towards formate(98.1%).On the other hand,the porous carbon fibers enable the uniform and stable dispersion of SnO_(2)nanoparticles,and this superior porous structure of carbon supports can also facilitate the exposure of the SnO_(2)nanoparticles on the reaction interface to a great ***,adequate contact between active sites,reactants,and electrolytes can significantly increase the metal utilization,eventually bringing forth a remarkable7.09 A/mg mass *** work might provide a useful idea for improving the utilization rate of metals in numerous electrocatalytic reactions.

关键词： CO_(2)electroreduction Support effect Porous carbon fiber Formate Mass activity

The transcriptome of MHV-infected RAW264.7 cells offers an alternative model for macrophage innate immunity research

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Animal Models and Experimental Medicine 2025年第1期8卷 57-66页

作者： Yun liu Ting-Ting Feng Wei Tong Zhi Guo Xia li Qi kong Zhi-Guang Xiang Institute of laboratory Animal Sciences Chinese Academy of Medical Sciences(CAMS)and Comparative Medicine CenterPeking Union Medical College(PUMC)BeijingP.R.China

background:Macrophages are the primary innate immune cells encountered by the invading coronaviruses,and their abilities to initiate inflammatory reactions,to main-tain the immunity homeostasis by differential polarization,to train the innate immune system by epigenic modification have been reported in laboratory animal ***:In the current in vitro research,murine macrophage RAW 264.7 cell were infected by mouse hepatitis virus,a coronavirus existed in *** 3-,6-,12-,24-,and 48-h post infection(hpi.),the attached cells were washed with PbS and harvested in Trizol *** The harvest is subjected to transcriptome ***:The transcriptome analysis showed the immediate(3 hpi.)up regulation of DEGs related to inflammation,like Il1b and *** related to M2 differential po-larization,like Irf4 showed up regulation at 24 hpi.,the late term after viral *** addition,DEGs related to metabolism and histone modification,like Ezh2 were de-tected,which might correlate with the trained immunity of ***:The current in vitro viral infection study showed the key innated im-munity character of macrophages,which suggested the replacement value of viral infection cells model,to reduce the animal usage in preclinical research.

关键词： coronavirus innate immunity macrophage transcriptome

lycium barbarum polysaccharide inhibits retinal neovascularization and inflammation in vitro and in vivo

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 216-221页

作者： bin Wu Xue Wang Wei Zhang Xin Wang Qi-Miao Wang Ya-Ju Pang Yi-Chun kong Tianjin Eye Hospital Tianjin Key Lab of Ophthalmology and Visual ScienceTianjin Eye InstituteClinical College of Ophthalmology Tianjin Medical UniversityTianjin 300102China Department of Ophthalmology Tianjin Hospital of Integrated Traditional Chinese and Western MedicineTianjin 300100China

AIM:To explore the effect and mechanism of lycium barbarum polysaccharide(lbP)inhibiting retinal ***:In vitro tests were performed on human retinal microvascular endothelial cells(HRECs)from three groups,including control group(normal oxygen),hypoxic group(hypoxia at 37℃,1%O_(2),5%CO_(2),and 94%N2),and lbP group(hypoxic group with lbP 100μg/ml).In vivo experiments,C57 mice were divided into three groups:control group(normal rearing group),the oxygen-induced ischemic retinopathy(OIR)group,and the OIR with 50 mg/kg lbP *** neovascularization was observed by fluorescein angiography and *** thickness was evaluated by Hematoxylin and eosin(HE)*** expression of epidermal growth factor receptor(EGFR),phosphatidylinositol 3-kinase(PI3K),mammalian target of rapamycin(mTOR),phosphorylated mammalian target of rapamycin(p-mTOR),protein kinase b(AKT),phosphorylated protein kinase b(p-AKT),interleukin-1β(Il-1β),inducible nitric oxide synthase(iNOS),and tumor necrosis factor-α(TNF-α)in each group were analyzed by Western ***-1βlevel in retina was analyzed using immunohistochemical ***:The increased area of neovascular clusters in OIR mice was significantly decreased by *** thickness of OIR mice was significantly thinner compared with normal oxygenated mice and was increased in lbP *** with those in the hypoxic groups,Western blotting of HRECs and retinal tissues revealed that the expression of EGFR,PI3K,p-mTOR,p-AKT,Il-1β,iNOS,and TNF-αdecreased in the lbP group but was still greater than that in control ***,Il-1βwas reduced in retinal sections treated with *** the scratch test,the cell migration of the hypoxic group was significantly greater than that of the control group,while lbP treatment attenuated this increase in ***:lbP reduces retinal neovascularization and inflammation in vivo and inhibits the migration of HRECs in vitro by regulating the EGFR/PI3K/Akt

关键词： lycium barbarum polysaccharide neovascularization epidermal growth factor receptor retina

Prediction of specific spoilage organisms in smoked chicken legs with modified atmosphere packaging at 4℃ using multivariate statistical analysis

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Food Science and Human Wellness 2025年第1期14卷 271-281页

作者： Qiang Wang Yubo Zhao Yumeng Sui Qian Chen Zhiming Dong Qian liu baohua kong ligang Qin College of Food Science Northeast Agricultural UniversityHarbin 150030China College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030China

The present study monitored bacterial succession,physicochemical properties,and volatile organic compounds(VOCs)changes in smoked chicken legs with modified atmosphere packaging(MAP,60% CO_(2) and 40%N_(2))during a 25-day storage period at 4℃.After 15 days of storage,S erratia proteamaculans and Pseudomonas fragi became the predominant ***,physicochemical properties changed significantly,as evidenced by an increase in thiobarbituric acid reactive substances and b*(yellowness)value,and a decrease in hardness.A total of 65 VOCs were identified during *** between bacterial succession and quality indicators(including VOCs and physicochemical properties)allowed the identification of 26 core dominant bacteria,including ***,Psychrobacter alimentarius,Pseudomonas putida,and Pseudomonas poae,which were positively related to spoilage VOCs(e.g.,1-octen-3-ol,1-pentanol,and 3-methyl-1-butanol)and could be defined as specific spoilage organisms(SSOs).The results of this study provide a systematic approach to predict SSOs in smoked chicken legs during storage,which can also provide a basis for product safety.

关键词： Smoked chicken legs Modified atmosphere packaging bacterial community Volatile organic compounds Specific spoilage organisms

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Feasible synthesis of porous h-bN by Mg^(2+)induced lattice dislocations for hydrogen and ammonia storage

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Nano Research 2025年第1期18卷 94-99页

作者： Xiaojia Huang Zihao Wang Yihan kong li Jiang baolin Wang Jiangtao Jia Heping Ma Guangshan Zhu Key laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Northeast Normal UniversityChangchun 130024China School of Chemical Engineering and Technology Xi’an Jiaotong University Xi’an 710049China

Hexagonal boron nitride(h-bN)is a two-dimensional(2D)layered material with a structure similar to graphite and it has potential as a hydrogen and ammonia storage ***,dense packing in the standard h-bN structure limits its surface area and prevents the b and N from being adsorption *** this study,the addition of Mg^(2+)during h-bN synthesis facilitated the growth of lattice dislocations and led to a crosslinked three-dimensional(3D)porous structure.A proposed formation mechanism for porous h-bN was confirmed by several characterization routes,most clearly by high-resolution transmission electron microscopy(HRTEM).Porous Mg/bNs exhibited high H_(2)and NH_(3)uptakes and showed potential for H_(2)and NH_(3)storage.

关键词： hexagonal boron nitride porous material dislocation gas storage