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Ru(Ⅱ)-catalyzed ortho-amidation and decarboxylation of aromatic acids: a versatile route to meta-substituted N-aryl benzamides

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science China Chemistry 2015年第8期58卷 1286-1291页

作者： Xian-Ying Shi Xue-Fen Dong Juan Fan Ke-Yan Liu Jun-Fa Wei Chao-Jun Li Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education) Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry and Chemical Engineering Shaanxi Normal University Department of Chemistry McGill University

Carboxylate as a promising and valuable directing group has attracted a great deal of ***,employing it as a traceless direction group has rarely been *** developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C–H functionalization followed by decarboxylation to afford the corresponding metasubstituted N-aryl benzamides,in which the carboxylate serves as a unique,removable directing ***,this protocol can provide an efficient alternative to access meta-substituted N-aryl benzamides,which are much more difficult to prepare than ortho-substituted analogues.

关键词： amides decarboxylation amidation C-H functionalization homogeneous catalysis

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Ten years of carbon-based metal-free electrocatalysts

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Carbon Energy 2019年第1期1卷 19-31页

作者： Rajib Paul Quanbin Dai Chuangang Hu Liming Dai Department of Macromolecular Science and Engineering Case Western Reserve UniversityClevelandOhio The UNSW-CWRU International Joint Laboratory School of Chemical EngineeringUniversity of New South WalesSydneyAustralia

Since the discovery of the first carbon-based metal-free electrocatalysts(C-MFECs,i.e.,N-doped carbon nanotubes)for the oxygen reduction reaction in 2009,the field of C-MFECs has grown enormously over the last 10 years.C-MFECs,as alternatives to nonprecious transition metals and/or precious noble metal-based electrocatalysts,have been consistently demonstrated as efficient catalysts for oxygen reduction,oxygen evolution,hydrogen evolution,carbon dioxide reduction,nitrogen reduction,and many other(electro-)chemical *** research and development of C-MFECs have indicated their potential applications in fuel cells,metal-air batteries,and hydrogen generation through water oxidation as well as electrochemical production of various commodity chemicals,such as ammonia,alcohols,hydrogen peroxide,and other useful *** research and development of C-MFECs would surely revolutionize traditional energy conversion and storage technologies with minimal environmental *** this short review article,we summarize the journey of C-MFECs over the past 10 years with an emphasis on materials development and their structure-property characterization for applications in fuel cells and metal-air *** challenges and future prospects of this emerging field are also discussed.

关键词： carbon electrocatalysis energy conversion energy storage metal-free electrocatalyst

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STUDIES ON RELATION BETWEEN INTRINSIC VISCOSITY OF POLYELECTROLYTES IN SOLUTIONS USED FOR LAYER-BY-LAYER SELFASSEMBLY AND THEIR CORRESPONDING ADSORPTION AMOUNTS IN THE RESULTANT MULTILAYER MEMBRANES

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Chinese Journal of Polymer science 2009年第3期27卷 297-306页

作者：钱锦文安全福 Phillip Choi Department of Polymer Science & Engineering Key Laboratory of Macromolecular Synthesis and Functionalization(Ministry of Education)Zhejiang University Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaCanada T6G 2G6

The adsorption amount of poly(styrene sulfonate) and poly(dimethyldiallyl ammonium chloride) (PSS/PDDA) self-assembled multilayer membranes in designed dipping solvents were measured by UV-Vis-spectroscopy and quartz crystal microbalance (QCM). Intrinsic viscosities of PSS and PDDA in corresponding dipping solvents were determined by an Ubbelohde viscometer. It is found that the adsorption amount of PSS/PDDA self-assembled multilayer membranes built up in different dipping solutions, added salt concentration, pH of solution and solvent quality, respectively changed oppositely with the corresponding intrinsic viscosity of PSS and PDDA in dipping solvents. A negative relation between the adsorption amount and intrinsic viscosity was revealed, and explained in term of the concept of excluded volume of polymer molecule in dilute solutions.

关键词： Self-assembled multilayer membrane PSS/PDDA Polyelectrolyte solution Intrinsic viscosity

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Strain Softening of Styrene-Isoprene-Styrene Copolymers under Large Amplitude Oscillatory Shear for Clarifying Payne Effect in Rubbers and Their Nanocomposites

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Chinese Journal of Polymer science 2023年第1期41卷 153-165页

作者： Xin-Peng Fan Yi-Hu Song Qiang Zheng Wan-Jie Wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou310027China Shanxi-Zheda Institute of New Materials and Chemical Engineering Taiyuan030000China College of Materials Science and Engineering Henan Key Laboratory of Advanced Nylon Materials and ApplicationZhengzhou UniversityZhengzhou450001China

To illustrate mechanisms of Payne effect in rubbers and their nanocomposites experiencing large amplitude oscillatory shear(LAOS),comparison studies were performed in styrene-isoprene-styrene(SIS)copolymers and their selectively crosslinked materials at temperatures below and above glass transition temperature of the polystyrene(PS)*** was found that under periodic dynamic shear,the strain softening is reversible when the polyisoprene(PI)phase,either crosslinked or not,is restricted by hard PS domains but it shows hysteresis once the PS domains *** strain softening can happen at the time scale of intrinsic Rouse relaxation of elastically active network *** stress of strain softening scales with number density of elastically active network strands,a simple relation being verified not only in the selectively crosslinked SIS copolymers but also in PI gum vulcanizates and carbon black filled PI *** effect is traditionally used to term strain softening of highly filled rubber vulcanizates under LAOS deformation while evidenced herein is that the Payne effect of highly filled rubber vulcanizates shares the mechanism being common to the strain softening of SIS copolymers.

关键词： Large amplitude oscillatory shear SIS Rubber nanocomposites Strain softening

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Efficient predictions of formation energies and convex hulls from density functional tight binding calculations

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Journal of Materials science & Technology 2023年第10期141卷 236-244页

作者： Anshuman Kumar Zulfikhar A.Ali Bryan M.Wong Materials Science&Engineering Program University of California-RiversideRiverside92521CAUSA Department of Physics&Astronomy University of California-RiversideRiverside92521CAUSA Materials Science&Engineering Program Department of Chemical&Environmental EngineeringDepartment of Physics&Astronomyand Department of ChemistryUniversity of California-RiversideRiverside92521CAUSA

Defects in materials significantly alter their electronic and structural properties,which affect the per-formance of electronic devices,structural alloys,and functional ***,calculating all the possible defects in complex materials with conventional Density Functional Theory(DFT)can be compu-tationally *** enhance the efficiency of these calculations,we interfaced Density Functional Tight Binding(DFTB)with the Clusters Approach to Statistical Mechanics(CASM)software package for the first *** SiC and ZnO as representative examples,we show that DFTB gives accurate results and can be used as an efficient computational approach for calculating and pre-screening formation ener-gies/convex *** DFTB+CASM implementation allows for an efficient exploration(up to an order of magnitude faster than DFT)of formation energies and convex hulls,which researchers can use to probe other complex systems.

关键词： CASM DFTB DFT Formation energy Convex hull

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Investigation of Cyanobacteria-Hosted Antibiotic Resistance Genes in Cyanohab-Impacted Drinking Water Sources

SSRN

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SSRN 2025年

作者： Volk, Abigail Mills, Molly Chae, Soryong Lee, Jiyoung Division of Environmental Health Sciences College of Public Health The Ohio State University ColumbusOH United States Environmental Sciences Graduate Program The Ohio State University ColumbusOH United States Department of Chemical and Environmental Engineering University of Cincinnati CincinnatiOH United States Department of Food Science and Technology The Ohio State University ColumbusOH United States Infectious Diseases Institute The Ohio State University ColumbusOH United States

Freshwater cyanobacterial blooms (cyanoHABs) produce cyanotoxins that cause human and animal illness. cyanoHABs are also hypothesized to play a role in the antibiotic resistome, but whether Cyanobacteria host clinically-relevant antibiotic resistant genes (ARGs) in the environment is largely unknown. To investigate this emerging issue, we looked for the presence of Cyanobacteria-hosted ARGs using shotgun metagenomic sequencing of drinking water source samples collected during the 2022 bloom season from Lake Erie and Grand Lake St. Marys (GLSM). . ARGs were annotated using DeepARG and Resistance Gene Identifier (RGI). Cyanobacteria were annotated to host genes conferring possible antibiotic resistance. Two of these genes were rpoB2 and arlR, but these genes were likely spurious hits on housekeeping genes. qac and OXA genes were also annotated. While those hits suggest potential resistance to clinical antibiotics, overall Cyanobacteria did not host appreciable clinically-relevant ARGs. Because the two drinking water sources historically have high cyanotoxin concentrations, selected cyanotoxins, Cyanobacteria, and ARGs were chosen for quantification. We found high levels of Microcystis in Lake Erie and Planktothrix in GLSM, and high microcystin concentrations in GLSM, supporting previous trends in these water bodies. This study takes a novel approach pairing the issues of cyanoHABs and ARGs together in two drinking water sources. In a changing climate, drinking water treatment strategies should consider the treatment and public health implications of multiple contaminants. © 2025, The Authors. All rights reserved.

关键词： Lakes

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Correlation between rheological behavior and structure of multi-component polymer systems

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science China Chemistry 2008年第1期51卷 1-12页

作者： ZUO Min1,2 ZHENG Qiang1 1 Key Laboratory of macromolecular Synthesis and Functionalization, Ministry of Education, department of Polymer science and engineering, Zhejiang University, Hangzhou 310027, China 2 department of chemical engineering, Hong Kong University of science and Technology, Clear Bay, Kowloon, Hong Kong 1. Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China 2. Department of Chemical Engineering Hong Kong University of Science and Technology Clear Bay Kowloon Hong Kong China

Rheological measurement has been an effective method to characterize the structure and properties for multiphase/multi-component polymers, owing to its sensitivity to the structure change of hetero- geneous systems. In this article, recent progress in the studies on the morphology/structure and rheological properties of heterogeneous systems is summarized, mainly reporting the findings of the authors and their collaborators, involving the correlation between the morphology and viscoelastic relaxation of LCST-type polymer blends, the microstructure and linear/nonlinear viscoelastic behavior of block copolymers, time scaling of shear-induced crystallization and rheological response of poly- olefins, and the relationship between the structure/properties and rheological behavior of filled polymer blends. It is suggested that a thorough understanding of the characteristic rheological response to the morphology/structure evolution of multiphase/multi-component polymers facilitates researchers’ op- timizing the morphology/structure and ultimate mechanical properties of polymer materials.

关键词： heterogeneous polymer systems morphology and structure rheological properties viscoelastic relaxation

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Ag-decorated 3D flower-like Bi_(2)MoO_(6)/rGO with boosted photocatalytic performance for removal of organic pollutants

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Rare Metals 2021年第5期40卷 1086-1098页

作者： Xin Liu Wei-Ya Huang Qin Zhou Xi-Rong Chen Kai Yang Dan Li Dionysios D.Dionysiou Faculty of Materials Metallurgical and ChemistryJiangxi University of Science and TechnologyGanzhou 341000China Environmental Engineering and Science Program Department of Chemical and Environmental EngineeringUniversity of CincinnatiCincinnatiOH 45221-0012USA College of Science HealthEngineering and EducationMurdoch UniversityMurdoch 6150Australia

A series of unique 3D flower-like Bi_(2)MoO_(6)(BMO)/reduced graphene oxide(rGO)heterostructured composites decorated with varying amounts of Ag nanoparticles(NPs)were *** morphological characteristics,structural features,energy band structures and photoelectrochemical properties were systematically *** the Ag/BMO/rGO ternary composites(AgBGy;y=1%,2%and 3%)demonstrated greater photocatalytic activity towards efficient removal of our selected organic models[methyl orange(MO),rhodamine B(RhB)and phenol],as compared with the BMO/rGO binary composites(BG-x;x=0.25,2,4 and 5).Particularly,AgBG-2%,which was synthesized with the addition of 2 wt% rGO and 2 wt%Ag in BMO,possessed superior photocatalytic *** fitted rate constants(k)for the photocatalytic degradation of RhB,MO and phenol using AgBG-2% were estimated to be 0.0286,0.0301 and 0.0165 min^(-1),respectively,which were over one order of magnitude greater than those obtained using pure *** factors may contribute to the observed enhancement,including greater specific surface area,enhanced light absorption,promoted spatial separation of electronhole(e^(-)-h^(+))pairs and their suppressed recombination,especially benefiting from the synergistic effects among BMO,rGO and Ag *** work suggests that the rational design of BMO/rGO/Ag ternary composite was an effective strategy to boost the photocatalytic activity of the resulting catalyst towards the highly efficient removal of organic pollutants from water.

关键词： Bi_(2)MoO_(6) Reduced graphene oxide Ag nanoparticles 3D flower-like morphology Photocatalytic degradation

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Functional surface modification of anisotropic biphasic nanoparticles for selective cell targeting

Functional surface modification of anisotropic biphasic nano...

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8th World Biomaterials Congress 2008, WBC 2008

作者： Yoshida, Mutsumi Roh, Kyung-Ho Lahann, Joerg Department of Chemical Engineering University of Michigan Ann Arbor MI United States Macromolecular Science and Engineering Program University of Michigan Ann Arbor MI United States

ISBN: (纸本)9781615670802

Biocompatibility of biphasic particles supports their use in biomedical applications. With the added capability of selectively targeting cells with directionality and controlled orientation, the biphasic nanocolloids may serve as a flexible platform requiring complex, multifunctionality, as both compartments can be independently loaded as well as be surface-modified to control orientation relative to the cell surface. Taken together these properties of anisotropic biphasic nanocolloids may enable capabilities such as self-assembly into three-dimensional tissue constructs or mimicry of subcellular organization which may not be achievable with more conventional, isotropic nanoparticles.

关键词： Nanoparticles

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Short-term biocompatibility of functionalized polymer coatings made by chemical vapor deposition polymerization

Short-term biocompatibility of functionalized polymer coatin...

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8th World Biomaterials Congress 2008, WBC 2008

作者： Yoshida, Mutsumi Elkasabi, Yaseen Lahann, Joerg Department of Chemical Engineering University of Michigan Ann Arbor MI United States Macromolecular Science and Engineering Program University of Michigan Ann Arbor MI United States

ISBN: (纸本)9781615670802

CVD polymerization of functionalized [2.2]paracyclophanes provides a generalized, simple process by which multiple reactivity can be afforded on various substrates with a range of geometry or topology. In addition, this method provides controllable ratios of presented functional groups and minimizes cross-reactivity of biomolecules as immobilization can be done in sequence. Initial assessment of biocompatibility of CVD coatings underscore the importance of controlled ratio of surface-presented functional groups, as small differences in the chemical composition of co-polymers can have significant impact in cellular response.

关键词： Biocompatibility

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