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While the functions of carbon materials with precisely controlled nanostructures have been reported in many studies, their chiral discriminating abilities have not been reported yet. Herein, chiral discrimination is achieved using helical carbon materials devoid of chiral attachments. A Fe

Five triphenyltriphenylamines with various substituents were investigated as precursors for near-infrared absorbing materials. Cyclic voltammetry (CV) studies showed that they all give stable radical cations in solution. The radical cations obtained by one-electron chemical oxidation of these compounds show strong absorption in the near-infrared region, and the position of the absorption is strongly influenced by the substituent. DFT (density functional theory) calculations suggest that the introduction of stronger electron-donating substituents would result in a smaller HOMO–SOMO energy gap and thus a larger long wavelength shift, which is consistent with the experimental results. On the other hand, strong electron-withdrawing substituents increase the HOMO–SOMO energy gap, resulting in a short wavelength shift. The position of the near-infrared absorption peak of the triphenylamine radical cation can be controlled to the longer or shorter wavelength direction depending on the substituent. A molecular design of near-infrared absorbing dyes utilizing the electronic effects of substituents is described.

Four triphenylamines with extended π-systems were synthesized. Cyclic voltammetry (CV) measurements showed that they gave radical cations, which are stable in solution. Radical cations obtained upon one electron chemical oxidation showed strong absorption in the near-infrared region. The radical cations of the naphthalene-substituted derivatives show a maximum absorption wavelength above 1000 nm and are classified as NIR-II dyes. Molecular design rules of novel near-infrared absorbing dyes are described.

The title crystalline compound, [Cu2(NCS)2(C9H16N2)2], was obtained from the reaction of copper(I) thiocyanate (CuSCN) with (N-prop-2-en-1-yl)piperidine-1-carbothioamide as a chelating and bridging thiourea ligand in chlorobenzene. The Cu2S2 core of the dimeric molecule is situated on a crystallographic inversion centre. The copper atom is coordinated by a thiocyanate nitrogen atom, each sulfur atom of the two thiourea ligands, and the C=C double bond of the ligand in a distorted tetrahedral geometry. The dimers are linked by N—H...S hydrogen bonds, forming a network extending in two dimensions parallel to (100).

In the crystal, two mol­ecules of the title compound form an inversion dimer, through C—H⋯π inter­actions, which further inter­acts with adjacent dimers to form a one-dimensional column structure., In the title mol­ecule, C48H33N, the central N atom shows no pyramidalization, so that the N atom and the three C atoms bound to the N atom lie almost in the same plane. The three para-phenyl­ene rings bonded to the N atom are in a propeller form. All of the naphthalene ring systems are slightly bent. In the crystal, mol­ecules form an inversion dimer, through two pairs of C—H⋯π inter­actions, which further inter­acts with the adjacent dimer via another two pairs of C—H⋯π inter­actions, forming a column structure along the a axis. There are no significant inter­actions between these column structures.

In the crystal, mol­ecules of the title compound, a potential ligand containing two 8-quinolinol and one 2-pyridine units, are linked by inter­molecular O—H⋯N and O—H⋯O quadruple hydrogen bonds, forming an inversion dimer with two (7) ring motifs. The dimers are associated through a C—H⋯O hydrogen bond and four C—H⋯π inter­actions., In the title compound, C24H15Cl2N3O2, one quinoline ring system is essentially planar and the other is slightly bent. An intra­molecular O—H⋯N hydrogen bond involving the hy­droxy group and a pyridine N atom forms an S(5) ring motif. In the crystal, two mol­ecules are associated into an inversion dimer with two R 2 2(7) ring motifs through inter­molecular O—H⋯N and O—H⋯O hydrogen bonds. The dimers are further linked by an inter­molecular C—H⋯O hydrogen bond and four C—H⋯π inter­actions, forming a two-dimensional network parallel to (001).

A triarylamine bearing three benzofuran rings was designed and successfully prepared in 64% yield. It exhibited absorption at 385 nm, and blue emission at around 440 nm with a fluorescence quantum ...

The mol-ecule of the title compound, C

We report basic diode characteristics and uniformity of Schottky contacts between printed Ni electrode and n-GaN on GaN epitaxial wafers annealed at 400, 500, and 600 °C. The Schottky barrier height of the samples annealed at 400 °C and 500 °C were as high as 1.21 eV, which is comparable to a conventional evaporated Ni contact. When the annealing temperature was 600 °C, rectifying the characteristics that were lost. Scanning internal photoemission microscopy (SIPM) showed that contacts annealed at 500 °C exhibited better uniformity than those at 400 °C. In contrast, the photo yield signal in SIPM of the contact annealed at 600 °C became weak and noisy due to the interfacial reaction between Ni and GaN. SIPM revealed that the contacts printed Ni electrode on GaN was more uniform than those of the printed Ag electrode. These results also show that SIPM is useful to estimate the uniformity of electrode contacts on semiconductors by non-destructive visualization.

The crystal structure of the title compound consists of a dimeric CuI complex possessing a Cu2S2 core and contains thio­cyanate anions and allyl­thio­urea derivatives as chelating and bridging ligands. The dimeric CuI complexes are linked by N—H⋯S hydrogen bonds, forming a network extending in two dimensions parallel to (100)., The title crystalline compound, [Cu2(NCS)2(C9H16N2)2], was obtained from the reaction of copper(I) thio­cyanate (CuSCN) with (N-prop-2-en-1-yl)piperidine-1-carbo­thio­amide as a chelating and bridging thio­urea ligand in chloro­benzene. The Cu2S2 core of the dimeric mol­ecule is situated on a crystallographic inversion centre. The copper atom is coordinated by a thio­cyanate nitro­gen atom, each sulfur atom of the two thio­urea ligands, and the C=C double bond of the ligand in a distorted tetra­hedral geometry. The dimers are linked by N—H⋯S hydrogen bonds, forming a network extending in two dimensions parallel to (100).

A triphenylamine with three benzothiophene rings was designed and successfully synthesized in 87% yield. The compound showed absorption at 386 nm and blue emission at around 442 nm, with a fluorescence quantum yield of 0.57. The compound showed high thermostability. The radical cation obtained by one-electron oxidation was stable in solution and showed a significant absorption in the NIR-II region (λmax = 1213 nm). DFT calculations confirmed the experimental data.

Interest in chiral substances has mainly focused on the substances themselves, but not on the accompanying space, especially regarding the pore alignment. As a method to form both the chiral substance and the accompanying space, cylindrical self-assembly of uniform polystyrene nanoparticles with fructose is carried out in the presence of both carbon and sodium alginate, which is followed by heat treatment in an inert atmosphere. The carbonization generates fructose-derived honeycomb-like carbon walls with helically aligned nanopores left after the polystyrene decomposition. The diffuse reflectance circular dichroism measurements give peaks with opposite signs for the d- and l-fructose-derived cylindrical carbons. Circularly polarized light sensitivity in transient photoconductivity is confirmed apparently in the carbon-based helical structures. This sensitivity as well as straightforward formation of composites with another component to give helicity shows potential applications of the helically aligned pores.

The synthesis and crystal structure of a coordination polymer composed of β-diketonato zinc(II) [Zn(dbm)2] and tri­aryl­amine-based bridging ligands (T3PyA) is reported. The asymmetric unit in the crystal consists of two independent halves of Zn(dbm)2, one T3PyA and one solvate THF. Each ZnII atom is located on an inversion centre and adopts an elongated octa­hedral coordination geometry. In the crystal, the coordination polymer chains are linked via C—H⋯π inter­actions into a three-dimensional framework., The reaction of bis­(3-oxo-1,3-di­phenyl­prop-1-enolato-κ2 O,O′)zinc(II), [Zn(dbm)2], with tris­[4-(pyridin-3-yl)phen­yl]amine (T3PyA) in tetra­hydro­furan (THF) afforded the title crystalline coordination polymer, {[Zn(C15H11O2)2(C33H24N4)]·C4H8O}n. The asymmetric unit contains two independent halves of Zn(dbm)2, one T3PyA and one THF. Each ZnII atom is located on an inversion centre and adopts an elongated octa­hedral coordination geometry, ligated by four O atoms of two dbm ligands in equatorial positions and by two N atoms of pyridine moieties from two different bridging T3PyA ligands in axial positions. The crystal packing shows a one-dimensional polymer chain in which the two pyridyl groups of the T3PyA ligand bridge two independent Zn atoms of Zn(dbm)2. In the crystal, the coordination polymer chains are linked via C—H⋯π inter­actions into a sheet structure parallel to (010). The sheets are cross-linked via further C—H⋯π inter­actions into a three-dimensional network. The solvate THF mol­ecule shows disorder over two sets of atomic sites having occupancies of 0.631 (7) and 0.369 (7).

Objective: n-3 polyunsaturated fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have beneficial effects on atherosclerosis. Although specific salutary actions have been reported, the detailed distribution of n-3 polyunsaturated fatty acids in plaque and their relevance in disease progression are unclear. Our aim was to assess the pharmacodynamics of EPA and DHA and their metabolites in atherosclerotic plaques. Approach and Results: Apolipoprotein E-deficient (Apoe −/− ) mice were fed a Western diet supplemented with EPA (1%, w/w) or DHA (1%, w/w) for 3 weeks. Imaging mass spectrometry analyses were performed in the aortic root and arch of the Apoe −/− mice to evaluate the distribution of EPA, DHA, their metabolites and the lipids containing EPA or DHA in the plaques. Liquid chromatography-mass spectrometry and histological analysis were also performed. The intima-media thickness of atherosclerotic plaque decreased in plaques containing free EPA and EPAs attached with several lipids. EPA was distributed more densely in the thin-cap plaques than in the thick-cap plaques, while DHA was more evenly distributed. In the aortic root, the distribution of total EPA level and cholesteryl esters containing EPA followed a concentration gradient from the vascular endothelium to the media. In the aortic arch, free EPA and 12-hydroxy-EPA colocalized with M2 macrophage. Conclusions: Administered EPA tends to be incorporated from the vascular lumen side and preferentially taken into the thin-cap plaque.

Silver microparticles (Ag MPs) are widely used in conductive pastes for printed flexible electronics because of their easier synthesis and lower cost than silver nanoparticles. However, the cyclic bending reliability of the printed conductive patterns containing Ag MPs needs to be improved to use the devices under bending conditions. In this work, the conductive paste was prepared by mixing two silver pastes containing silver microparticles and silver microflakes (Ag MFs). These mixed pastes were screen-printed on PEN films to fabricate conductive patterns. Although the electrical resistivity increased 3.7 times as the Ag MFs content increased from 0 to 30 wt%, the bending stability was improved by Ag MFs in conductive patterns because the formation of crack under cyclic bending stress was suppressed. The increase of the resistivity was due to decreasing the number of electrical contacts caused by the formation of voids within the patterns containing a large amount of Ag MFs. These results are useful for designing printed conductive metal patterns with high bending stability.

The recent growing interest in the applications of gold nanowires (AuNWs) as flexible materials has raised the fundamental issue of how their mechanical properties are related to their morphology. In this work, to address this issue, the systematic synthesis of AuNWs, their structural analysis, and their rheological investigation were demonstrated. The structural analysis of AuNWs was performed based on TEM observations and light-scattering experiments. From these observations, it was found that the length of AuNWs varies from nanometer to micrometer depending on the reaction time while a constant width of 1.6 nm is maintained. On the basis of static light-scattering experiments and a wormlike chain model, the structural parameters of AuNWs during their growth were successfully obtained. When the contour length of AuNWs reached around 5 μm, the AuNW solution showed non-Newtonian behavior and appeared to behave as a gel. Dynamic viscoelasticity measurements indicated that such viscous behavior is responsible for entanglement between AuNWs. It is concluded that AuNWs are analogous with conventional polymers in terms of both their structure and their rheological behavior.

In the title compound, there is an intra­molecular O—H⋯N hydrogen bond forming an S(9) ring motif. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds forming inversion dimers with an R 4 4(10) ring motif. The dimers are linked by C—H⋯N hydrogen bonds, forming ribbons along [01-1]., In the title compound, C22H19ClN4O, the quinolinol moiety is almost planar [r.m.s. deviation = 0.012 Å]. There is an intra­molecular O—H⋯N hydrogen bond involving the hy­droxy group and a pyridine N atom forming an S(9) ring motif. The dihedral angles between the planes of the quinolinol moiety and the pyridine rings are 44.15 (9) and 36.85 (9)°. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds forming inversion dimers with an R 4 4(10) ring motif. The dimers are linked by C—H⋯N hydrogen bonds, forming ribbons along [01-1]. The ribbons are linked by C—H⋯π and π–π inter­actions [inter-centroid distance = 3.7109 (11) Å], forming layers parallel to (01-1).

Multiple photosynthetic reaction centers have successfully been constructed using a supramolecular complex of zinc porphyrin dendrimer [D(ZnP)16] with pyridylnaphthalenediimide (PyNIm) in benzonitrile. The apparent formation constant determined from the fluorescence quenching of the singlet excited state of porphyrin moieties by PyNIm is significantly larger than that determined from the UV-vis spectral change. This indicates that efficient energy migration occurs between the porphyrin units of the dendrimer prior to the electron transfer from the singlet excited state of zinc porphyrin to PyNIm. The charge-separated (CS) state has been successfully detected as the transient absorption spectrum in the laser flash photolysis. The CS lifetime of in the supramolecular complex of D(ZnP)16 with PyNIm was determined to be 0.83 ms at 298 K.

A low-temperature pressureless bonding process using a mixture of trimodal-sized Ag nanoparticles was proposed to form excellent Cu-to-Cu joints. Cu-to-Cu joints formed using the mixed Ag nanoparticles at 350°C for 5 min showed bonding strength of 13.7 MPa, in spite of the bonding process without pressure. Elongated dimples observed on the fracture surface of the Cu-to-Cu joint strongly support the effect of the trimodal mixture system of Ag nanoparticles in the low-temperature pressureless bonding process.

Tetradecanoate-stabilized Ag–Pd alloy nanoparticles (NPs) were quantitatively synthesized by the controlled thermolysis of silver tetradecanoate and palladium tetradecanoate in the presence of trip...

A low-temperature bonding process to form joints with high strength and ionic migration resistance using mixed Cu–Ag nanoparticles was studied. Although it was difficult to obtain strong joints using Cu nanoparticles, with the addition of Ag nanoparticles to the Cu nanoparticles the bonding strength of the Cu-to-Cu joints increased. The joints formed by the mixed Cu–Ag nanoparticles at 350°C exhibited a high bonding strength of ~50 MPa. Counterelectrodes made of the mixed Cu–Ag nanoparticles had four times higher ionic migration resistance compared with counterelectrodes made only of Ag nanoparticles.

高強度と耐イオンマイグレーション性を有する銅–銅接合を得るために，3種類の銅ナノ粒子（平均粒子径：d=7.2 nm, 64.8 nm, 498 nm）および銀–銅混合ナノ粒子を用いた低温接合プロセス（250℃～400℃）を検討した。銅ナノ粒子を用いた接合では，平均粒子径64.8 nmの銅ナノ粒子を用いた場合に最も高い強度を示した。銅ナノ粒子（d=498 nm）と銀ナノ粒子（d=7.9 nm）の銀–銅混合ナノ粒子の場合には，50%Ag–50%Cuの配合比において最も高い接合強度が得られた。50%Ag–50%Cu混合ナノ粒子を用いた焼成電極は，銀ナノ粒子の焼成電極よりも優れた耐イオンマイグレーション性を示した。

A size-controlled synthesis of gold nanoparticles has been developed by the thermolysis of AuCl(SMe2) in the presence of alkylamines at 120 °C. In the procedure, the key intermediate was [Au(NH2R)2]Cl, detected by electrospray ionization (ESI) mass spectrometry. This thermally unstable intermediate was reduced by alkylamines under mild conditions to produce alkylamine-capped gold nanoparticles. The average diameters of the gold nanoparticles could be regulated in a range from 4.3 to 6.1 nm by applying primary alkylamines with alkyl chains of different lengths. Larger gold nanoparticles with diameters from 10 to 22 nm were prepared by a combination of alkylamines and alkylcarboxylic acids with various lengths of the alkyl chains. The gold nanoparticles were characterized by transmission electron microscopy (TEM), UV/Vis absorption spectroscopy, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), gas chromatography/mass spectroscopy (GC/MS), and thermogravimetric and differencial thermal analyses (TG/DTA)

A supramolecular ferrocene-zinc porphyrin-pyridylnaphthalenediimide triad is formed by coordinating the pyridine entity of pyridylnaphthalenediimide with the zinc ion of a ferrocene-zinc porphyrin dyad in benzonitrile. The fluorescence of the zinc porphyrin moiety is efficiently quenched by photoinduced electron transfer from the singlet excited state of the zinc porphyrin moiety to the naphthalenediimide moiety. This is followed by subsequent electron transfer from the ferrocene moiety to the zinc porphyrin radical cation to produce the final charge-separated state, ferricenium ion-zinc porphyrin-naphthalenediimide radical anion, which is successfully detected as a transient absorption spectrum in the laser flash photolysis. The decay of the charge-separated state obeys first-order kinetics irrespective of the initial concentration of the charge-separated state to afford a long lifetime (320 μs). This is the first example of a supramolecular triad that has a long lifetime as compared with the charge-separated state lifetime of the component dyad.