catena-Poly[[[bis­[4-(1H-1,3,7,8-tetra­azacyclo­penta­[l]phenanthren-2-yl)­phenol-κ2 N 7,N 8]lead(II)]-μ-4,4′-oxy­dibenzoato-κ3 O,O′:O′′] dihydrate]

The carboxyl­ate dianion in the title compound, [Pb(C14H8O5)(C19H12N4O)2]·2H2O, uses one carboxyl­ate group to O,O′-chelate a bis­[4-(1H-1,3,7,8-tetra­azacyclo­penta­[l]phen­anthren-2-yl)phenol]-chelated PbII atom and uses its other carboxyl­ate group to bind to another PbII atom in an irregular monodentate manner. The PbII atom exists in an undefined seven-coordinate geometry in the chain structure; the lone pair is stereochemically active. Adjacent chains are linked by inter­molecular O—H⋯N, N—H⋯O and O—H⋯O hydrogen bonds that involve the uncoordinated water mol­ecules to form a three-dimensional network

Poly[di-μ5-adipato-κ4 O:O′:O′′:O′′′,O′′′-μ4-adipato-κ4 O:O′:O′′:O′′′-bis­[2-phenyl-1H-1,3,7,8-tetra­azacyclo­penta­[l]phenanthrene-κ2 N 7,N 8]tricobalt(II)]

In the title polymer, [Co3(C6H8O4)3(C19H12N4)2]n, two adipate dianions (C6H8O4 2−) occupy general positions and two are situated on different inversion centres. The two on general positions bind through their four O atoms to five 2-phenyl-1H-1,3,7,8-tetra­azacyclo­penta­[l]phenanthrene-chelated CoII ions, whereas the two on special positions bind to only four. Of the three Co atoms, two are chelated by N-heterocycles; the third is bonded to six O atoms. The bonding mode of the dianion gives rise to a three-dimensional network structure; the network is further consolidated by N—H⋯O hydrogen bonds

Bis[2-((4,6-dimethyl­pyrimidin-2-yl){2-[(4,6-dimethyl­pyrimidin-2-yl)sulfan­yl]eth­yl}amino)­eth­yl] disulfide

Bis[2-(4,6-dimethyl­pyrimidin-2-ylsulfan­yl)eth­yl]amine under hydro­thermal conditions has unexpectedly been transformed into the title compound, C32H44N10S4. In the title mol­ecule, the zigzag 3,10-diaza-6,7-disulfanyldodecyl skeleton has two dimethyl­pyrimidinylsulfanyl groups at both ends, and the aza atoms each carry a dimethyl­pyrimidinyl unit. The N atoms in the skeleton show a planar coordination

Bis[2-(2-pyridyl­sulfan­yl)eth­yl]ammonium perchlorate

The cation and anion of the title salt, C14H18N3S2 +·ClO4 −, lie on a twofold rotation axis. The cation is a W-shaped entity with the aromatic rings at the ends; the ammonium NH2 + group is a hydrogen-bond donor to the pyridyl N atoms. The perchlorate ion has one O atom disordered over two sites in a 0.50:0.50 ratio

The effects of water and microstructure on the performance of polymer electrolyte fuel cells

n this paper, we present a comprehensive non-isothermal, one-dimensional model of the cathode side of a Polymer Electrolyte Fuel Cell. We explicitly include the catalyst layer, gas diffusion layer and the membrane. The catalyst layer and gas diffusion layer are characterized by several measurable microstructural parameters. We model all three phases of water, with a view to capturing the effect that each has on the performance of the cell. A comparison with experiment is presented, demonstrating excellent agreement, particularly with regard to the effects of water activity in the channels and how it impacts flooding and membrane hydration. We present several results pertaining to the effects of water on the current density (or cell voltage), demonstrating the role of micro-structure, liquid water removal from the channel, water activity, membrane and gas diffusion layer thickness and channel temperature. These results provide an indication of the changes that are required to achieve optimal performance through improved water management and MEA-component design. Moreover, with its level of detail, the model we develop forms an excellent basis for a multi-dimensional model of the entire membrane electrode assembly

Cloning and Comparative Studies of Seaweed Trehalose-6-Phosphate Synthase Genes

The full-length cDNA sequence (3219 base pairs) of the trehalose-6-phosphate synthase gene of Porphyra yezoensis (PyTPS) was isolated by RACE-PCR and deposited in GenBank (NCBI) with the accession number AY729671. PyTPS encodes a protein of 908 amino acids before a stop codon, and has a calculated molecular mass of 101,591 Daltons. The PyTPS protein consists of a TPS domain in the N-terminus and a putative TPP domain at the C-terminus. Homology alignment for PyTPS and the TPS proteins from bacteria, yeast and higher plants indicated that the most closely related sequences to PyTPS were those from higher plants (OsTPS and AtTPS5), whereas the most distant sequence to PyTPS was from bacteria (EcOtsAB). Based on the identified sequence of the PyTPS gene, PCR primers were designed and used to amplify the TPS genes from nine other seaweed species. Sequences of the nine obtained TPS genes were deposited in GenBank (NCBI). All 10 TPS genes encoded peptides of 908 amino acids and the sequences were highly conserved both in nucleotide composition (>94%) and in amino acid composition (>96%). Unlike the TPS genes from some other plants, there was no intron in any of the 10 isolated seaweed TPS genes

Confinement of carbon dots localizing to the ultrathin layered double hydroxides toward simultaneous triple-mode bioimaging and photothermal therapy

It is a great challenge to develop multifunctional nanocarriers for cancer diagnosis and therapy. Herein, versatile CDs/ICG-uLDHs nanovehicles for triple-modal fluorescence/photoacoustic/two-photon bioimaging and effective photothermal therapy were prepared via a facile self-assembly of red emission carbon dots (CDs), indocyanine green (ICG) with the ultrathin layered double hydroxides (uLDHs). Due to the J-aggregates of ICG constructed in the self-assembly process, CDs/ICG-uLDHs was able to stabilize the photothermal agent ICG and enhanced its photothermal efficiency. Furthermore, the unique confinement effect of uLDHs has extended the fluorescence lifetime of CDs in favor of bioimaging. Considering the excellent in vitro and in vivo phototherapeutics and multimodal imaging effects, this work provides a promising platform for the construction of multifunctional theranostic nanocarrier system for the cancer treatment

Radio pulsations from a neutron star within the gamma-ray binary LS I +61° 303

LS I +61° 303 is one of the rare gamma-ray binaries that emit most of their luminosity in photons with energies beyond 100 MeV (ref. ). It is well characterized—the ~26.5 day orbital period is clearly detected at many wavelengths—and other aspects of its multifrequency behaviour make it the most interesting example of its class. The morphology of high-resolution radio images changes with orbital phase, displaying a cometary tail pointing away from the high-mass star component and LS I +61° 303 also shows superorbital variability. A couple of energetic (~10 erg s), short, magnetar-like bursts have been plausibly ascribed to it. Although the phenomenology of LS I +61° 303 has been the subject of theoretical scrutiny for decades, there has been a lack of certainty regarding the nature of the compact object in the binary that has hampered our understanding of the source. Here, using observations with the Five-hundred-meter Aperture Spherical radio Telescope, we report the existence of transient radio pulsations from the direction of LS I +61° 303 with a period P = 269.15508 ± 0.00016 ms at a significance of >20σ. These pulsations strongly argue for the existence of a rotating neutron star within LS I +61° 303.This work made use of the data from FAST. FAST is a Chinese national mega-science facility, operated by National Astronomical Observatories, Chinese Academy of Sciences. We acknowledge the use of the ATNF Pulsar Catalogue. S.-S.W. and B.-J.W. thank Z. Pan for discussions on the FAST data analysis. S.-S.W. thanks Z.-X. Wang, S.-N. Zhang and K. Lee for many valuable discussions. J.L., D.F.T. and A.P. acknowledge discussions with the international team on ‘Understanding and unifying the gamma rays emitting scenarios in high mass and low mass X-ray binaries’ of the ISSI (International Space Science Institute), Beijing. We acknowledge support from National Key R&D programme of China grant numbers 2017YFA0402602 and 2021YFA0718500, National SKA Program of China grant numbers 2020SKA0120100 and 2020SKA0120201, National Natural Science Foundation of China grant numbers U2038103, 11733009, U2031205, U1938109 and 11873032, the Youth Innovation Promotion Association of the CAS (grant id 2018075), the Chinese Academy of Sciences Presidential Fellowship Initiative 2021VMA0001, National Foreign Experts Program of Ministry of Science and Technology of the People’s Republic of China grant number G2021200001L and the International Visiting Professorship programme of the University of Science and Technology of China grant number 2021BVR05. S.-S.W. acknowledges financial support from the Jiangsu Qing Lan Project. D.F.T. also acknowledges grants PID2021-124581OB-I00, PGC2018-095512-B-I00 and Spanish programme Unidad de Excelencia ‘María de Maeztu’ grant number CEX2020-001058-M. A.P. acknowledges financial support from the Italian Space Agency (ASI) and National Institute for Astrophysics (INAF) under grant agreement numbers ASI-INAF I/037/12/0 and ASI-INAF n.2017-14-H.0, from INAF ’Sostegno alla ricerca scientifica main streams dell’INAF’, Presidential Decree 43/2018 and from PHAROS COST Action number 16214