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An inverted triplesalen ligand by a convergent synthesis and its influence on trinuclear Fe_3~Ⅲ complexes

Science China Chemistry 2012年第6期55卷 951-966页

作者： FELDSCHER Bastian KRICKEMEYER Erich MOSELAGE Marc THEIL Hubert HOEKE Veronika KAISER Yvonne STAMMLER Anja BGGE Hartmut glaser thorsten Lehrstuhl für Anorganische Chemie I Fakultt für Chemie Universitt Bielefeld Universittsstr. 25 D-33615 Bielefeld Germany

The inverted triplesalen ligand H 6 feld Me has been synthesized from 2,4,6-triformyl-phloroglucinol and a ketimine salen half-unit in a convergent synthesis. NMR, IR, and UV-vis spectroscopy reveal that this ligand is not in the O-protonated tautomer but in the N-protonated tautomer with substantial heteroradialene contribution. This ligand and the conventional triplesalen ligand H 6 talen t-Bu 2 have been used to synthesize the trinuclear Fe III complexes [(feld Me )(FeCl) 3 ] and [(talen t-Bu 2 )(FeCl) 3 ], respectively. The molecular structures of these complexes were obtained by single-crystal X-ray diffraction. Two trinuclear Fe III complexes of [(feld Me )(FeCl) 3 ] dimerize via two Fe-phenolate bonds, whereas due to steric hindrance no dimerization is observed for [(talen t-Bu 2 )(FeCl) 3 ]. The structural data also reveal some heteroradialene contribution in the trinuclear complexes. Whereas UV-vis and M bauer spectroscopy are not suitable to distinguish between the two complexes, FT-IR spectra show characteristic features due to the different substitution patterns of the conventional and the inverted triplesalen ligands. Another handle is provided by electrochemistry. Whereas both complexes exhibit an irreversible oxidation wave (0.94 V vs. Fc + /Fc for [(feld Me )(FeCl) 3 ] and 0.84 V vs. Fc + /Fc for [(talen t-Bu 2 )(FeCl) 3 ]), which is assigned to the oxidation of the central backbone, higher potential oxidations are reversible for [(talen t-Bu 2 )(FeCl) 3 ]) but irreversible for [(feld Me )(FeCl) 3 ]. This is attributed to the reversible oxidation of the terminal phenolates in the di-tert-butyl substituted [(talen t-Bu 2 )(FeCl) 3 ] in contrast to the mono-methyl-substituted phenolates in [(feld Me )(FeCl) 3 ]. The magnetic properties of [(talen t-Bu 2 )(FeCl) 3 ] reveal a very small ferromagnetic coupling with significant zero-field splitting of the FeⅢ S = 5/2 ions. In contrast, the dimerization of two trinuclear complexes in [(feld Me )(FeCl) 3 ] r

关键词：三核配合物氯化铁复合物合成收敛反铁磁相互作用单晶X-射线衍射紫外可见光谱

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An inverted triplesalen ligand by a convergent synthesis and its influence on trinuclear FeXII3 complexes

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中国科学：化学 2012年第6期42卷 897-900页

作者： Bastian FELDSCHER Erich KRICKEMEYER Marc MOSELAGE Hubert THEIL Veronika HOEKE Yvonne KAISER Anja STAMMLER Hartmut BGGE thorsten glaser Lehrstuhl f黵 Anorganische Chemie I Fakult鋞 f黵 Chemie Universit鋞 Bielefeld Universit鋞sstr. 25 D-33615 Bielefeld Germany

The inverted triplesalen ligand H6feldMehas been synthesized from 2,4,6-triformyl-phloroglucinol and a ketimine salen half-unit in a convergent synthesis. NMR, IR, and UV-vis spectroscopy reveal that this ligand is not in the O-protonated tautomer but in the N-protonated tautomer with substantial heteroradialene contribution. This ligand and the conventional triplesalen ligand H6talent-Bu2 have been used to synthesize the trinuclear FeⅢcomplexes [(feldMe)(FeCl)3] and [(talent-Bu2)(FeCl)3], respectively. The molecular structures of these complexes were obtained by single-crystal X-ray diffraction. Two trinuclear FeⅢcomplexes of [(feldMe)(FeCl)3] dimerize via two Fe-phenolate bonds, whereas due to steric hindrance no dimerization is observed for [(talent-Bu2)(FeCl)3]. The structural data also reveal some heteroradialene contribution in the trinuclear complexes. Whereas UV-vis and M??bauer spectroscopy are not suitable to distinguish between the two complexes, FT-IR spectra show characteristic features due to the different substitution patterns of the conventional and the inverted triplesalen ligands. Another handle is provided by electrochemistry. Whereas both complexes exhibit an irreversible oxidation wave (0.94 V vs. Fc+/Fc for [(feldMe)(FeCl)3] and 0.84 V vs. Fc+/Fc for [(talent-Bu2)(FeCl)3]), which is assigned to the oxidation of the central backbone, higher potential oxidations are reversible for [(talent-Bu2)(FeCl)3]) but irreversible for [(feldMe)(FeCl)3]. This is attributed to the reversible oxidation of the terminal phenolates in the di-tert-butyl substituted [(talent-Bu2

关键词：三核配合物合成收敛反铁磁相互作用复合物单晶X-射线衍射紫外可见光谱铁配合物

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Epidemiology and clinical characteristics of pediatric osteomyelitis in northern California

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World Journal of Pediatrics 2023年第6期19卷 609-613页

作者： Xiao Ben Wang Navendu Samant Justin Searns Carol glaser Department of Pediatrics UCLA Medical Center10833 Le Conte AvenueA2-383 MDCCLos AngelesCA 90095USA Division of Research Kaiser Permanente Northern CaliforniaOaklandCAUSA Department of Pediatrics University of ColoradoChildren's Hospital ColoradoAuroraCOUSA California Department of Public Health CARichmondUSA

Pediatric osteomyelitis is a serious infection in children leading to significant morbidity and hospitalization[1].Infections most commonly occur in the long bones,and 52%-70% are caused by Staphylococcus aureus(***)[2-4].Methicillin-resistant Staphylococcus aureus(MRSA)has been associated with higher rates of complications for children with acute osteomyelitis.

关键词： Epidemiology myelitis acute

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Emerging Therapeutic Strategies in The Fight Against Primary Biliary Cholangitis

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Journal of Clinical and Translational Hepatology 2023年第4期11卷 949-957页

作者： Abigail Medford Jonathan Childs Ashleigh Little Sanjukta Chakraborty Leonardo Baiocchi Gianfranco Alpini Shannon glaser Department of Medical Physiology Texas A&M University School of MedicineBryanTXUSA Hepatology Unit University of Tor VergataRomeItaly Division of Gastroenterology and Hepatology Department of MedicineIndiana University School of MedicineIndianapolisINUSA

The liver has a vital role in many metabolic and regulatory processes in the *** biliary cholangitis(PBC),previously known as primary biliary cirrhosis,is a chronic cholestatic autoimmune disease of the intrahepatic bile ducts associated with loss of tolerance to mitochondrial *** this time there is no definitive cure for PBC;however,ursodeoxycholic acid(UDCA)has been shown to reduce injury when administered as the first line of *** therapeutics can be given concurrently or as an alternative to UDCA to manage the symptoms and further curb disease ***,a liver transplant is the only potentially curative option when the patient has developed end-stage liver disease or intractable *** review aims to delineate the pathogenesis of primary biliary cholangitis and shed light on current therapeutic strategies in the treatment of PBC.

关键词： Cholestatic liver disease Therapeutic approaches Biliary epithelia ursodeoxycholic acid

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An adaptive Markov chain algorithm applied over map-matching of vehicle trip GPS data

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Geo-Spatial Information Science 2021年第3期24卷 484-497页

作者： Bilge Kaan Karamete Louai Adhami Eli glaser Engineering GeospatialKinetica DB IncArlingtonVAUSA

Markov chains have frequently been applied to match the probable routes with a set of GPS trip data that a pilot vehicle is emitting over a specific graph road network. This class of mapmatching (MM) algorithms presently demonstrates and involve statistical and ad-hoc measures to drive the Markov chain transitional probabilities in picking the best route combinations constrained over the graph road network. In this study, we have devised an adaptive scheme to modify the Markov Chain (MC) kernel window as we move along the GPS samples to reduce the mistakes that can happen by the use of narrower MC widths. The measure for temporarily increasing the MC window width is chosen to be the ratio between the geodesic distance of current route to the actual geodesic distance between each pair of GPS samples. This adaptive use of MC has shown to have hardened the results significantly with tolerable computational cost increase. The details of the overall algorithm are depicted by the example routes extracted from various vehicle trips and the results are shown to validate the usefulness of the algorithm in practice.

关键词： Hidden Markov chain(HMC) map-matching(MM) graph networks

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Promotion effect of niobium on ceria catalyst for selective catalytic reduction of NO with NH3

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Journal of Rare Earths 2022年第10期40卷 1535-1545页

作者： Bolin Zhang Lifeng Deng Michael Liebau Yingjie Ren Chunyun Luo Bo Liu Shengen Zhang Roger glaser Institute for Advanced Materials and Technology University of Science and Technology BeijingBejing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399China Jiangsu Longkingcotech Co. Ltd.Yancheng224000China Institute of Chemical Technology Universit at LeipzigLeipzig04103Germany

The CeO_(2),Ce-Nb-O_(x) and Nb_(2)O_(5) catalysts were synthesized by citric acid method and the promotion effect of Nb on ceria for selective catalytic reduction(SCR)of NO with NH_(3) was *** catalytic activity measurements indicate that the mixed oxide Ce-Nb-O_(x) presents a higher SCR activity than the single oxide CeO_(2) or Nb_(2)O_(5) *** addition,the Ce-Nb-O_(x) catalyst shows high resistance towards H_(2)O and SO_(2) at 280℃.The Raman,X-ray photoelectron spectra and temperature programmed reduction with H_(2) results indicate that the incorporation of Nb provides abundant oxygen vacancies for capturing more surface adsorbed oxygen,which provides a superior redox capability and accelerates the renewal of active ***,the Fourier transform infrared spectra and temperature programmed desorption of NH_(3) results suggest that niobium pentoxide shows high surface acidity,which is partly retained in the Ce-Nb-O_(x) catalyst possessing a high content of Lewis and Br?nsted acid ***,the incorporation of Nb improves both the redox and acidic capacities of Ce-Nb-O_(x) catalyst for the SCR ***,the redox behavior is primarily taken on Ce and the acidity is well improved by Nb,so the synergistic effect should exist between Ce and *** terms of the reaction mechanism,in situ DRIFT experiments suggest that both NH_(3) on Lewis acid sites and NH_(4)^(+) on Bronsted acid sites can react with NO species,and adsorbed NO and NO_(2) species can both be reduced by NH_(3).In the SCR process,O_(2) primarily acts as the accelerant to improve the redox and acid cycles and plays an important *** work proves that the combination of redox and acidic properties of different constituents can be feasible for catalyst design to obtain a superior SCR performance.

关键词： Cerium-niobium Selective catalytic reduction Redox behavior Acid cycle Synergistic effect Rare earths

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Synergistic effect of cobalt and niobium in Co_(3)-Nb-O_(x)on performance of selective catalytic reduction of NO with NH_(3)

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Rare Metals 2022年第1期41卷 166-178页

作者： Bo-Lin Zhang Li-Feng Deng Bo Liu Chun-Yun Luo Michael Liebau Shen-Gen Zhang Roger glaser Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399China Jiangsu Longkingcotech Co. Ltd.Yancheng 224000China Institute of Chemical Technology Universita¨t LeipzigLeipzig 04103Germany e-mail:roger.glaeser

Combining the redox properties of Co and the acid properties of Nb in a Co_(3)-Nb-O_(x)catalyst is shown to provide superior performance in the selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).Co_(3)O_(4)shows average activity,however,it exhibits a poor N_(2)***_(2)O_(5)is not active for NH_(3)-***,the mixed Co_(3)-Nb-O_(x) catalyst shows higher NO conversion and N_(2)selectivity than the single Co_(3)O_(4)and Nb_(2)O_(5)catalysts at 100–300℃.The results of temperature programmed reduction by H_(2)and X-ray photoelectron(XP)spectra indicate that the addition of Nb changes the chemical states of Co and decreases the concentration of Co^(3+) and Oa,adjusting the activity for catalytic oxidation to a moderate *** suppresses the formation of undesired N_(2)O from the over-oxidation of NH_(3).Incorporation of Co and Nb into one solid synergistically couples their redox behavior and surface acidity,ensuring the high catalytic activity and N2 selectivity in NH3-SCR.

关键词： Co-Nb Selective catalytic reduction Lowtemperature Acid property Redox behavior

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Strengthening the scientific evidence base of a new climate agreement

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Ecosystem Health and Sustainability 2015年第9期1卷 18-22页

作者： Gisbert glaser International Council for Science(ICSU) 5 Rue Auguste VacquerieParisFrance 75116

Ahead of the forthcoming global intergovernmental climate meeting in Paris,scientists met in Paris in July at a large scientific conference calling for an ambitious agreement aimed at holding global warming to 2℃.With agriculture,forestry,and other land use contributing 24%of total greenhouse gas(GHG)emissions(2000-2009),there is potential for significant ecosystem-based mitigation ***,maintaining healthy ecosystems represents,in many situations,the most efficient way of *** paper highlights some scientific aspects,as presented at the conference,related to ecosystem-based adaptation and *** calls for enhanced cooperation between scientists,policy makers,and other stakeholders.

关键词： adaptation agriculture climate change ecosystems international agreements mitigation science–policy links stakeholder cooperation sustainable development

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Import Determinants of Organelle-Specific and Dual Targeting Peptides of Mitochondria and Chloroplasts in Arabidopsis thaliana

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Molecular Plant 2014年第1期7卷 121-136页

作者： Changrong Ge Erika Spanning Elzbieta glaser Ake Wieslander Department of Biochemistry and Biophysics Center for Biomembrane Research Stockholm University SE-106 91 Stockholm Sweden Medical Inflammation Research Department of Medical Biochemistry and Biophysics Karolinska Institute SE-171 77 Stockholm Sweden

Most of the mitochondrial and chloroplastic proteins are synthesized in the cytosol as precursor proteins carrying an N-terminal targeting peptide （TP） directing them specifically to a correct organelle. However, there is a group of proteins that are dually targeted to mitochondria and chloroplasts using an ambiguous N-terminal dual targeting peptide （dTP）. Here, we have investigated pattern properties of import determinants of organelle-specific TPs and dTPs combining mathematical multivariate data analysis （MVDA） with in vitro organellar import studies. We have used large datasets of mitochondrial and chloroplastic proteins found in organellar proteomes as well as manually selected data sets of experimentally confirmed organelle-specific TPs and dTPs from Arabidopsis thaliana. Two classes of organelle-specific TPs could be distinguished by MVDA and potential patterns or periodicity in the amino acid sequence contributing to the separation were revealed, dTPs were found to have intermediate sequence features between the organelle-specific TPs. Interestingly, introducing positively charged residues to the dTPs showed clustering towards the mitochondrial TPs in silico and resulted in inhibition of chloroplast, but not mitochondrial import in in vitro organellar import studies. These findings suggest that positive charges in the N-terminal region of TPs may function as an ＇avoidance signal＇ for the chloroplast import.

关键词： dual targeting ambiguous targeting signal mitochondria chloroplast protein import partial least square discriminant analysis Arabidopsis thaliana.

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Effect of biochar fertilizers on amino acid variability of Secale cereale and Lupinus angustifolius

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Biochar 2019年第2期1卷 187-201页

作者： Katja Wiedner Corinna Schimpf Steven Polifka Bruno glaser Soil Biogeochemistry Institute of Agronomy and Nutritional SciencesMartin Luther University Halle-WittenbergVon-Seckendorff-Platz 306120 Halle(Saale)Germany

Little is known on the effects of biochar on N uptake and amino acid variability in crops such as winter rye and narrow-leafed lupine despite the fact that amino acids are important indicators,for food quality and plant stress.N uptake of both crops showed contrasting results when treated with different biochar *** amino acid contents referred to total nitro-gen generally tend to decrease in rye grains in the presence of biochar;whereas lupine seeds were more or less unaffected by biochar combined with mineral fertilizer or *** lupine seeds,total amino acid contents significantly increased when biochar was mixed with digestate but decreased when mixed with fermented ***,one of the most limiting amino acids in cereals,reached the recommended value of 4 g kg^(−1) in rye grain for most biochar *** lupine seeds,lysine decreased when biochar had been applied but were still in the recommended range when used as animal ***,an indicator for plant stress,significantly decreased(−49%)in rye when 2 Mg biochar ha^(−1) was added in combination with mineral *** contrast,proline increased when biochar was added to organic(digestate and compost)fertilizers(up to 43%).Further biochar research should focus much more on food quality,which is a key challenge for global food production.

关键词： Food quality Protein Lupine Winter rye Yield

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