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1. Local Glass Transition Temperature T _g ( z ) Profile in Polystyrene next to Polybutadiene with and without Plasticization Effects

   https://doi.org/10.1002/macp.201700328  

   Kasavan, Benjamin L.; Baglay, Roman R.; Roth, Connie B. (November 2017, Macromolecular Chemistry and Physics)

   Abstract Rubber toughening of glassy polystyrene (PS) has been manufactured commercially for decades as high impact polystyrene, where rubbery poly‐butadiene (PB) inclusions are added to modify the PS matrix response to deformation and impact. In this study, measurements of the local glass transition temperatureT_g(z) of PS next to PB rubber are presented, expanding the previous data to a polymer with a much lowerT_gvalue (PBT_g^bulk= −96 °C). After accounting for a small molecule additive present in the commercial PB sample that would otherwise migrate over to the PS domain causing plasticization, it is found that theT_g(z) profile in PS next to PB is consistent with previous results. It is also demonstrated that these broad and asymmetric experimentally observedT_g(z) profiles are not caused by the migration of low molecular weight chains across the interface by comparing samples made with two different poly(n‐butyl methacrylate) molecular weights. 

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2. Structural and genetic basis for the binding of a mouse monoclonal antibody to Flavobacterium psychrophilum lipopolysaccharide

   https://doi.org/10.1111/jfd.13958  

   Cisar, John_O; Wang, Xiaocong; Woods, Robert_J; Cain, Kenneth_D; Wiens, Gregory_D (June 2024, Journal of Fish Diseases)

   Abstract A mouse monoclonal antibody (mAb FL100A) previously prepared againstFlavobacterium psychrophilum(Fp) CSF259‐93 has now been examined for binding to lipopolysaccharides (LPS) of this strain andFp950106‐1/1. The corresponding O‐polysaccharides (O‐PS) of these strains are formed by identical trisaccharide repeats composed ofl‐Rhamnose (l‐Rha), 2‐acetamido‐2‐deoxy‐l‐fucose (l‐FucNAc) and 2‐acetamido‐4‐R₁‐2,4‐dideoxy‐d‐quinovose (d‐Qui2NAc4NR₁) where R₁represents a dihydroxyhexanamido moiety. The O‐PS loci of these strains are also identical except for the gene (wzy1orwzy2) that encodes the polysaccharide polymerase. Accordingly, adjacent O‐PS repeats are joined throughd‐Qui2NAc4NR₁andl‐Rha bywzy2‐dependent α(1–2) linkages inFpCSF259‐93 versuswzy1‐dependent β(1–3) linkages inFp950106‐1/1. mAb FL100A reacted strongly withFpCSF259‐93 O‐PS and LPS but weakly or not at all withFp950106‐1/1 LPS and O‐PS. Importantly, it also labelled cell surface blebs on the former but not the latter strain. Additionally, mAb binding was approximately 5‐times stronger to homologousFpCSF259‐93 LPS than to LPS from a strain with a different R‐group gene. A conformational epitope for mAb FL100A binding was suggested from molecular dynamic simulations of each O‐PS. Thus,FpCSF259‐93 O‐PS formed a stable well‐defined compact helix in which the R₁groups were displayed in a regular pattern on the helix exterior while unreactiveFp950106‐1/1 O‐PS adopted a flexible extended linear conformation. Taken together, the findings establish the specificity of mAb FL100A for Wzy2‐linkedF. psychrophilumO‐PS and LPS. 

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3. A New Platform of B/N‐Doped Cyclophanes: Access to a π‐Conjugated Block‐Type B ₃ N ₃ Macrocycle with Strong Dipole Moment and Unique Optoelectronic Properties

   https://doi.org/10.1002/anie.202200612  

   Li, Pengfei; Shimoyama, Daisuke; Zhang, Niu; Jia, Yawei; Hu, Guofei; Li, Chenglong; Yin, Xiaodong; Wang, Nan; Jäkle, Frieder; Chen, Pangkuan (March 2022, Angewandte Chemie International Edition)

   Abstract We herein describe a new design principle to achieve B/N‐doped cyclophane where an electron‐donor block of three triarylamines (Ar₃N) and an acceptor block of three triarylboranes (Ar₃B) are spatially separated on opposite sides of the π‐extended ring system. DFT computations revealed the distinct electronic structure of theblock‐type macrocycleMC‐b‐B3N3with a greatly enhanced dipole moment and reduced HOMO–LUMO energy gap in comparison to its analogue with alternating B and N sites,MC‐alt‐B3N3. The unique arrangement of borane acceptor Ar₃B and amine donor Ar₃N components inMC‐b‐B3N3induces exceptionally strong intramolecular charge transfer in the excited state, which is reflected in a largely red‐shifted luminescence at 612 nm in solution. The respective linear open‐chain oligomerL‐b‐B3N3was also synthesized for comparison. Our new approach to donor–acceptor macrocycles offers important fundamental insights and opens up a new avenue to unique optoelectronic materials. 

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4. Investigation of Pb–B Bonding in PbB ₂ (BO) _n ⁻ ( n = 0–2): Transformation from Aromatic PbB ₂ ⁻ to Pb[B ₂ (BO) ₂ ] ^−/0 Complexes with BB Triple Bonds

   https://doi.org/10.1039/D3CP02800C  

   Chen, Qiang; Chen, Wei-Jia; Wu, Xin-Yao; Chen, Teng-Teng; Yuan, Rui-Nan; Lu, Hai-Gang; Yuan, Dao-Fu; Li, Si-Dian; Wang, Lai-Sheng (February 2024, Physical Chemistry Chemical Physics)

   Joint photoelectron spectroscopy and first-principles theory investigations indicate that the Pb-doped PbB₂(BO)_n⁻clusters (n= 0−2) undergo a transformation from σ + π doubly aromatic triangle PbB₂⁻to PbB₄(BO)₂^−/0complexes with a B≡B triple bond. 

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5. Studies of Functional Defects for Fast Na‐Ion Conduction in Na _{3− y} PS _{4− x} Cl _x with a Combined Experimental and Computational Approach

   https://doi.org/10.1002/adfm.201807951  

   Feng, Xuyong; Chien, Po‐Hsiu; Zhu, Zhuoying; Chu, Iek‐Heng; Wang, Pengbo; Immediato‐Scuotto, Marcello; Arabzadeh, Hesam; Ong, Shyue_Ping; Hu, Yan‐Yan (January 2019, Advanced Functional Materials)

   Abstract All‐solid‐state rechargeable sodium (Na)‐ion batteries are promising for inexpensive and high‐energy‐density large‐scale energy storage. In this contribution, new Na solid electrolytes, Na_3−yPS_4−xCl_x, are synthesized with a strategic approach, which allows maximum substitution of Cl for S (x= 0.2) without significant compromise of structural integrity or Na deficiency. A maximum conductivity of 1.96 mS cm⁻¹at 25 °C is achieved for Na_3.0PS_3.8Cl_0.2, which is two orders of magnitude higher compared with that of tetragonal Na₃PS₄(t‐Na₃PS₄). The activation energy (E_a) is determined to be 0.19 eV. Ab initio molecular dynamics simulations shed light on the merit of maximizing Cl‐doping while maintaining low Na deficiency in enhanced Na‐ion conduction. Solid‐state nuclear magnetic resonance (NMR) characterizations confirm the successful substitution of Cl for S and the resulting change of P oxidation state from 5+ to 4+, which is also verified by spin moment analysis. Ion transport pathways are determined with a tracer‐exchange NMR method. The functional detects that promote Na ‐ion transport are maximized for further improvement in ionic conductivity. Full‐cell performance is demonstrated using Na/Na_3.0PS_3.8Cl_0.2/Na₃V₂(PO₄)₃with a reversible capacity of ≈100 mAh g^‐1at room temperature. 

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