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The development of novel luminescent materials with multi-stimuli responsive and multi-functional properties is required. In this work, we designed and synthesized a novel AIE-based fluorenone derivative, MBPF. The donor–acceptor–donor (D–A–D) structure promoted the intermolecular hydrogen bonding capacity of the exposed oxygen atom in fluorenone. MBPF displayed three different aggregation morphologies: an amorphous floccule Y-MBPF with yellow-green luminescence, a block crystal O-MBPF with orange luminescence, and a needlelike crystal R-MBPF with red emission. They all exhibited reversible stimuli-response phase transitions to temperature and shear, accompanied by fluorescence switching. The orange crystal O-MBPF was also sensitive to isotropic hydrostatic pressure with prominent and contrasting luminescent conversion. Furthermore, we prepared MBPF nanocrystallites and encapsulated them with DSPE–PEG and the monoclonal antibody cetuximab (C225) to obtain MBPF-C225 NPs, which were biocompatible and photostable. They could be used for specific cancer cell imaging through receptor-mediated endocytosis.

This paper selects the data of China’s A-share listed companies from 2012 to 2018, and uses propensity score matching and difference-in-difference method to analyze the impact of private placement on enterprise innovation. The research found that: private placement will promote enterprise innovation; after further subdividing the nature of ownership, compared with state-owned enterprises, the role of private placement in promoting enterprise innovation is more obvious in non-state-owned enterprises; after subdividing the characteristics of the sector, compared to the Main board listed companies, the promotion effect of private placements on enterprise innovation is even more pronounced on GEM and SME board listed companies. Based on the empirical research in this article, regulators should further improve the private placement system, while encouraging investors to actively exercise their supervisory power, supervise the use of funds raised by private placement and actively support enterprise innovation activities, so as to enhance the innovation vitality of the entire economic market.

The Yellow River is an important ecological shelter zone and economic belt in China. However, rapid urbanization and industrialization has produced a fragile ecological environment conditions and unbalanced economic development in the Yellow River Basin (YRB). Ecological protection and high-quality development of the YRB has been China's national strategy since 2019. As the only coastal province with the largest economy and population in the YRB, the sustainable development of Shandong Province is of great importance in the region. This study evaluated the dynamic trend of sustainability levels of the nine cities in Shandong Province in the YRB through emergy analysis. Emergy-based indicators were established and analyzed from 2010 to 2019, taking account of the ecological service emergy (ESE) needed to dilute pollutants and emergy equivalent loss (EEL) on ecosystem quality and human health damage. Results showed that emergy sustainable indicators (ESI) in Tai'an, Heze, Dezhou, and Liaocheng ranged from 1 to 10, which had the potential for sustainable development. The ESI value of Jinan, Jining, Zibo, Dongying, and Binzhou was less than 1, which indicated that these cities were under great ecological pressure. The value of emergy indicators for sustainable development (EISD) of the nine cities all declined from 2010 to 2016, but remained stable from 2017 to 2019. Based on findings from the emergy analysis regarding policy implications and local conditions, the study concludes by providing proposals to improve regional sustainability.

A cyclometalated platinum phenylacetylide [(L)Pt(CC–ph)] {L = 4-[p-(diphenylamino)phenyl]-6-phenyl-2,2′-bipyridine} has been successfully synthesized and characterized. Its oxidative electropolymerization film with a non-diffusion controlled redox behaviour and an inverse dependence of AC impedance on its thickness has also been obtained by cyclic voltammetry on the working ITO electrode. The hybrid film possesses interesting dual-wavelength electrochromic properties in visible and near-infrared spectral regions. The low-voltage-controlled near-infrared electrochromism at 1520 nm under +1.0 V exhibits a moderate optical contrast ratio (ΔT% = 49%), a fast response time (8.4 s for the coloration step and 1.1 s for the bleaching step), and high coloration and bleaching efficiency (242.0 and 232.5 C−1 cm2). The solid-state display device shows a significant colour change from orange to dark-blue (ΔT% = 51%) with excellent electrochromic properties (6.5 s for the coloration step and 9.5 s for the bleaching step, and coloration and bleaching efficiencies of 203.5 and 241.3 C−1 cm2) and long-term stability at 773 nm between −0.5 and +1.6 V.

The cyclometalated Pt(II) acetylide derivative with a 1,3-bis(N-octyl-benzimidazol-2-yl)benzene (N^C^N) ligand and a free terpyridine (TPY) receptor has been successfully synthesized and characterized. X-ray crystallography shows its inefficient conjugation degree between the [(N^C^N)Pt] and TPY planes. This bifunctional complex shows an enhanced 1MLCT/LLCT absorption band (e = 3.30 × 104 dm3 mol−1 cm−1) centered at λmax = 365 nm, and the well-resolved vibronic-structured 3MLCT/LLCT emission bands (Φ = 0.08, τ = 3.43 μs) in the range of ca. 475–700 nm. Consecutive titrations show that added Zn2+ and Eu(HFA)3 bond to its free TPY receptor with 1 : 2 and 1 : 1 stoichiometry to form the heterotrinuclear Pt–Zn–Pt (Ka = 3.48 × 104 mol−1 dm3) and heterodinuclear Pt–Eu (Ka = 1.73 × 104 mol−1 dm3) complexes, respectively. A sensitizing effect of Zn2+ on the TPY unit, and the incomplete d → f energy transfer from the [(N^C^N)Pt(II)] antenna donor to the Eu(III) center with maximum efficiency of 51.8% are observed. Using an in situ mixed titration strategy, the R/G/B emission triads consisted of red [(TPY)Eu(HFA)3] and green [(N^C^N)Pt(II)] dual phosphorescence and blue [(TPY)Zn(TPY)] fluorescence, which can be well balanced to realize the white-light-emission with CIE coordinates (x = 0.36, y = 0.36) by precisely controlling the molar ratio (9 : 1 : 2) of the parent complexes, Eu(HFA)3 and Zn(ClO4)2.

A noncentrosymmetric (NCS) alkali-metal borophosphate CsBP2O6(OH)2 (CBPO) containing a unique borophosphate anionic partial structure has been obtained through a mixed-solvent thermal method. Its structure could be regarded as a 1-D chain that is built by Cs+ cations and a unique anionic chain [BP2O6(OH)2]∞n- composed of BO4 and PO3(OH) groups. CBPO possesses a wide UV-vis transparent range and shows a strong SHG response. Moreover, we have well explored and established the origin of the SHG effect by dipole moment and PDOS calculations. This work will help inspire and stimulate scientists to discover more such excellent NLO materials.

The ultraviolet (UV)-blue radiation of sunlights usually induce the photodegradation of organic photovoltaic materials, leading to the lifetime degeneration of solar cells. A luminescent converter layer for UV-blue to visible photoconversion is a promising way to harvest UV-blue sunlights and transforms them into visible lights that can be directly absorbed by active materials of solar cells. In this work, highly transparent Ag/YVO4:Eu3+/PMMA film were fabricated, which could not only filter out the harmful UV light as well as absorb multiband wavelengths ranging of 400–540 nm, but also could convert them into red lights which match well with band gap of photovoltaic materials. Then, we experimentally and theoretically investigated the luminescence enhancements with various Ag nanoparticles (NPs) size, concentration and excitation wavelengths. The luminescent enhancements were realized under the multiband wavelength excitation ranging of 280–538 nm. The maximum luminescence enhancement is 23-fold for Ag/YVO4:Eu3+/PMMA film under the excitation wavelength of 468 nm matching well with the localized surface plasmonic resonance (LSPR) of Ag NPs. Furthermore, we provide evidence that such enhancement is resulted from excitation field enhancement instead of Purcell effect. Our findings provide us a thinking on designing highly effective and transparent plasmon/luminescent converter, which may be utilized to improve the photostability and efficiency of solar cells.

Magnetic CoFe2O4 nanoparticles were encapsulated with fibrous silica shells via a simple self-assembly process to fabricate a novel, bifunctional, nanocomposite of fibrous-structured silica-CoFe2O4. The nanocomposite not only exhibited fibrous spherical morphology, typical mesoporous structure, high specific surface area and narrow size distribution, but also excellent superparamagnetic features and good monodispersity. Further study demonstrated that doxorubicin hydrochloride could be easily loaded onto the CoFe2O4@FMS (fibrous morphology silica) nanoplatforms and released with pH stimuli. Additionally, MTT assay confirmed that CoFe2O4@FMS NPs have good biocompatibility. Therefore, a novel nanocarrier based on CoFe2O4@FMS is proposed, with potential application for targeted cancer therapy.

The modification of upconversion luminescence (UCL) in In 2 O 3 :Yb 3+ , Er 3+ inverse opal photonic crystals (IOPCs) was investigated. The spontaneous decay rate (SDR) of 4 S 3/2 - 4 I 15/2 in IOPCs was suppressed as high as 2.6 times in contrast to the reference (REF) sample due to the modification of effective refractive index. It is significant to observe that the temperature quenching and concentration quenching in the In 2 O 3 :Yb 3+ , Er 3+ IOPCs was greatly suppressed due to the thin layer structure and connected air cavity.

Multifunctional MWCNTs@CoFe2O4@mSiO2@NaYF4:Yb3+,Er3+ nanoparticles have been synthesized via a simple self-assembled process. The composites exhibited good magnetism properties, porous structure, and strong up-conversion fluorescence, which offered by ultraminiature CoFe2O4 nanoparticles, mesoporous SiO2 shell, and up-conversion nanoparticles, respectively. Such multifunctional nanocomposites can be utilized as drug delivery carrier. The doxorubicin hydrochloride loaded MWCNTs@CoFe2O4@mSiO2@NaYF4:Yb3+,Er3+ nanoplatforms showed excellent pH-responsive drug release character within 48 h. Additionally, MTT assay confirmed that the nanoparticles possess good biocompatibility.

All-inorganic perovskite quantum dots (PQDs) have attracted tremendous attention due to their extraordinary optical properties, especially CsPbBr3 QDs with their high stability and photoluminescence efficiency. However, studies investigating the biosensing capabilities of PQDs are still limited. In this work, we designed a visible -light-triggered photoelectrochemical (PEC) sensor based on CsPbBr3 QDs for the first time. The immobilized three-dimensional (3D) ZnO inverse opal photonic crystals (IOPCs) were applied to dihydronicotinamide adenine dinucleotide (NADH) sensing. It was found that the CsPbBr3 QDs, as a photoactive material in a PEC sensor, can expand the photocurrent response of the PEC sensor to the visible region, as well as boost its conductivity. This PEC sensor based on a ZnO/CsPbBr3 electrode demonstrates sensitive detection of NADH in phosphate buffer saline solution and serum, with a good linear range from 0.1 μM to 250 μM and a low detection limit of 0.010 μM. Our strategy offers a new approach to perovskite QD-based PEC sensing, which could be more sensitive and convenient for clinical analysis.

The cyclometalated dinuclear platinum acetylide with a 9,9-dioctylfluorene spacer and two terminal triphenylamine groups has been successfully synthesized and characterized by 1H NMR, 13C NMR and MALDI-TOF MS. The active triphenylamine groups efficiently trigger the oxidative electropolymerization process to form a reddish-orange film on the working Pt and ITO electrodes by cyclic voltammetry. The compact film shows a polyaniline-like AC impedance behavior and an inverse dependence of AC impedance on its thickness. As a result of switching of the MLCT/ICT and dication absorption transitions between 0 and + 1.8 V, this metallopolymer film exhibits the near-IR electrochromism with significant optical contrast ratio (ΔT% = 78.3% at λ = 775 nm), comparative response time (3.8 s for the coloration step and 11.0 s for the bleaching step) and high anodic coloration efficiency (CE = 208.3 C− 1·cm2).

The triphenylamine derivative with a terpyridine-like unit, {4-[p-(N,N-diphenylamino)-phenyl]-2,6-di(pyrazin-2-yl)pyridine}, and its doubly N-methylated salt have been successfully synthesized and characterized. The salt with much enhanced intramolecular D-A interaction shows a remarkable bathochromical shift of its absorption bands and a fluorescence quenching effect. And its oxidative electropolymerization film with tunable thickness and non-diffusion controlled redox behavior has also been obtained by cyclic voltammetry on the working ITO electrode. The film possesses an independent dual-wavelength response in visible (400–850 nm) and near-infrared (850–2100 nm) spectral regions under different voltages. The low-voltage-controlled electrochromism displays significant color change from pale yellow to dark blue (ΔT% = 78%) with fast response time (6 s for the coloration step and 3 s for the bleaching step), high coloration and bleaching efficiencies (363.7 and 238.5 C-1·cm2) at λmax = 730 nm between −0.2 and + 1.2 V.

In2O3:Yb3+,Er3+ nanorod flowers (NRFs) are prepared by a simple hydrothermal method, where sucrose was used as a ligand. The obtained In2O3:Yb3+,Er3+ NRFs were carefully characterized by scanning electron microscopy (SEM), power X-ray diffraction (XRD), transmission electron microscopy (TEM) and steady/transient spectroscopy. The dependence of the upconversion luminescence (UCL) of In2O3:Yb3+,Er3+ NRFs on morphology, Yb3+ concentration and excitation power was carefully discussed. It is found that the luminescence intensity ratio of the red emission to green emission (R/G) depended on the morphology and Yb3+ concentration, and the green emissions are dominantly resulting from a three-photon populating process with higher Yb3+ doping concentration. More importantly, the concentration quenching in the In2O3:Yb3+,Er3+ NRFs was greatly suppressed due to boundary effects, and is beneficial for lighting and photon energy conversion devices.

A cyclometalated Pt(II) acetylide derivative bearing a carbazole donor and a terpyridine (TPY) receptor has been successfully synthesized and characterized. X-ray crystallography shows its monoclinic crystal system with the P2(1)/c space group and the three-component co-planarity molecular structure. This efficient π-conjugation system displays an intense low-energy absorption band (e = 1.51 × 104 dm3 mol−1 cm−1) at λmax = 442 nm and a strong phosphorescence emission (Φ = 0.045) at λmax = 596 nm in an air-saturated CH2Cl2 solution at room temperature, resulting from the dπ(Pt) → π*(C^N^N) metal-to-ligand charge transfer (MLCT) mixing with the π(CC–Ar) → π*(C^N^N) ligand-to-ligand charge transfer (LLCT) transition. With the introduction of the TPY receptor, this complex possesses ca. 1.6-fold luminescence-enhancing response for Zn2+ and Cd2+ but dramatic luminescence quenching response toward other common transition metal cations. Consecutive titrations exhibit that the added metal ions bond to its free TPY receptor with 1 : 2 stoichiometry to form the heterotrinuclear (Pt–M–Pt) complex. The Fe2+-quenched and Zn2+-enhanced luminescence behaviors with the maximum PET efficiency of 92.4% and 62.7%, respectively, strongly suggest the presence of the intra-molecular energy transfer between the [M(TPY)2]2+ core and the terminal phosphorescent Pt(II) complex units.

The new polar 3D cadmium molybdotellurite Cd3(MoO4)(TeO3)2 was obtained by means of a high-temperature solid-state method. Cd3(MoO4)(TeO3)2 is a monoclinic crystal system, and it exhibits the polar space group P21 (No. 4). The structure of Cd3(MoO4)(TeO3)2 can be viewed as a complicated 3D architecture that is composed of distorted CdOn (n = 6, 7) polyhedra, TeO3 trigonal pyramids, and MoO4 polyhedra. The compound features the first 3D NCS cadmium molybdotellurite with 1D 4- and 6-MR channels and a polar structure originating from the TeO3 groups, MoO4 groups, and displacements of d10 Cd2+ cations. The results were further confirmed by calculations of the net polarization. The UV–vis spectrum and thermal properties indicate that Cd3(MoO4)(TeO3)2 exhibits a broad transparent region and excellent thermal stability. SHG tests of Cd3(MoO4)(TeO3)2 revealed that its response is approximately the same as that of KH2PO4 at the same grain size between 105 and 150 μm and that it is phase-matchable.

All-inorganic perovskite quantum dots (PQDs) have attracted tremendous attention due to their extraordinary optical properties, especially CsPbBr3 QDs with their high stability and photoluminescence efficiency. However, studies investigating the biosensing capabilities of PQDs are still limited. In this work, we designed a visible -light-triggered photoelectrochemical (PEC) sensor based on CsPbBr3 QDs for the first time. The immobilized three-dimensional (3D) ZnO inverse opal photonic crystals (IOPCs) were applied to dihydronicotinamide adenine dinucleotide (NADH) sensing. It was found that the CsPbBr3 QDs, as a photoactive material in a PEC sensor, can expand the photocurrent response of the PEC sensor to the visible region, as well as boost its conductivity. This PEC sensor based on a ZnO/CsPbBr3 electrode demonstrates sensitive detection of NADH in phosphate buffer saline solution and serum, with a good linear range from 0.1 μM to 250 μM and a low detection limit of 0.010 μM. Our strategy offers a new approach to perovskite QD-based PEC sensing, which could be more sensitive and convenient for clinical analysis.

A cyclometalated platinum chloride [(L)PtCl] {L = 4-[p-(diphenylamino)phenyl]-6-phenyl-2,2'-bipyridine} was successfully synthesized and characterized by (1)H NMR, (13)C NMR, MALDI-TOF MS, elemental analysis, and X-ray crystallography. Its oxidative electropolymerization proceeds smoothly on the working Pt and ITO electrodes by cyclic voltammetry. The film thickness can be easily tuned by controlling the CV scan number. The orange hybrid polymer film shows the nondiffusion-controlled redox processes and a unusually inverse dependence of ac impedance on its thickness. As a result of switching of the MLCT/ICT and dication absorption transitions, the adherent metallopolymer film exhibits the low-voltage-controlled anodic coloration near-IR electrochromism with significant optical contrast ratio (ΔT% = 88.8% at 820 nm), fast response time (1.9 s for the coloration step and 2.3 s for the bleaching step), and high coloration efficiency (CE = 363.3 C(-1)·cm(2)).

A novel open-framework copper borophosphate, Na5KCu3[B9P6O33(OH)3]·H2O (), has been synthesised by a boric acid flux method. Its structure can be viewed as a 3-D open framework constructed by the connection of Cu(II)O6 octahedra and 1-D (4,4)-connected borophosphate anionic structures composed of trigonal-planar BO2(OH) groups, tetrahedral BO4 and PO4 groups. The compound not only features a novel borophosphate anionic partial structure containing 1-D 12-MR channels, but also exhibits ferromagnetic interactions and high catalytic activity for the oxidative degradation of chitosan.

A new 3-D open-framework cadmium borovanadate NNU-5 with 6-connected topology was hydrothermally obtained and structurally characterized. It not only features new cadmium(II) borovanadate which possesses an open-framework structure with unique plane-shaped channels, but also exhibits interesting absorption properties and high catalytic activities for the oxidation of cyclohexanol.

Cobalt ferrite nanoparticles loaded on multiwalled carbon nanotube (MWCNT) magnetic hybrids have been demonstrated to be promising magnetic resonance imaging contrast agents and drug carriers. However, the hydrophobic, less biocompatible characteristics and low loading capacity for the drug hamper their wide biological applications. To solve the above problem, an alternative strategy is to coat the MWCNTs@CoFe

A novel open-framework copper borovanadate, with a 6-connected topological net and 1D 8-membered ring channels, has been obtained for the first time. The compound not only exhibits a unique -B3 O7 (OH)-Cu-B(OH)3 linkage and features the largest ratio between TM2+ (Cu2+ ) and the borovanadate anion, but also possesses enhanced catalytic performance, high recyclability, and stability during the oxidation of benzylic C-H bonds.

The new polar 3D cadmium molybdotellurite Cd

Two cyclometalated Pt(II) complexes, [(L1)PtCl] and [(L2)PtCl] (where HL1 = 4-[p-(N-octyl-N-phenyl)amino]-phenyl-6-phenyl-2,2′-bipyridine and HL2 = 4-{p-[p-(N,N′-dioctyl-N′-phenyl)phenyldiamino]}-phenyl-6-phenyl-2,2′-bipyridine), have been synthesized and characterized by 1H NMR, mass spectrometry (MS) and elemental analysis. The structure of complex [(L1)PtCl] has been revealed by X-ray crystallography. Both of the complexes possess the intense and red-shifted metal-to-ligand charge transfer (1MLCT) (dπ(Pt) → π*(L)) transitions (e ∼ 104 dm3 mol−1 cm−1). Complex [(L1)PtCl] displays strong phosphorescence (λmax = 597 nm) in CH2Cl2 solution at room temperature and efficient electropolymerization behavior to form an electrochromic film with times of 5.8 s for the coloration step and 5.2 s for the bleaching step, an optical contrast of 70.5%, a black coloration efficiency of 441.4 C−1 cm2 and a bleaching efficiency of 489.1 C−1 cm2. Complex [(L2)PtCl] shows sensitive pH dependent luminescent properties, which are attributed to the inhibition of the intramolecular charge transfer (ICT) process through the protonation of the aniline dimer unit in the cyclometalating ligand.

Nine cyclometalated Pt(II) complexes, i.e. [( L n )PtCl], [( L n )Pt(C CC 6 H 5 )], [( L n )Pt(C C-TPA)] ( n = 1–3) (where H L 1 = 4-phenyl-6-phenyl-2,2′-bipyridine, H L 2 = 4-ethoxycarbonyl-6-phenyl-2,2′-bipyridine, H L 3 = 4-ethoxycarbonyl-6-phenyl-2-(2′-pyrazinyl)pyridine and TPA = triphenylamine), have been successfully synthesized and verified by 1 H NMR, MS and elemental analysis. The X-ray crystallography of [( L 2 )Pt(C C-TPA)] reveals that the coordinate geometry of Pt atom is a distorted square planar configuration with bond distances and angles in the normal range and the presence of the metal–metal and π–π interactions. The introduction of the electron-withdrawing unit, such as ethoxycarbonyl and/or pyrazinyl groups, into the (C^N^N) ligand with the electron-donating triphenylamine acetylide as the secondary ligand, systematically forms the strong D–A systems, which show the extended responses to the visible light resulting from the significant splitting and red-shift of the metal-to-ligand charge transfer (MLCT) and the ligand-to-ligand charge transfer (LLCT) transition bands in the absorption spectra. [( L n )PtCl] and [( L n )Pt(C C-Ph)] complexes display long-lived yellow to deep red phosphorescence in fluid solution at room temperature, but the emissions of [( L n )Pt(C C-TPA)] complexes are quenched by the intramolecular photoinduced electron transfer (PET) process with the TPA group acting as an electron donor. Their electrochemical behaviors are consistent with the spectroscopic results.

A chitosan/TiO2 hybrid film, as a powerful antifungal material for controlling southern corn leaf blight, which is caused by the fungus Bipolaris maydis (B. maydis), was prepared and characterized. Its antifungal activity toward B. maydis was studied, and the experimental results indicate that it had multiple attractive antifungal properties as follows: (1) it displayed strong antifungal activity against B. maydis, with an inhibition ratio of 100% under both visible-light irradiation and in a dark environment; (2) it exhibited a superior antifungal efficacy of 100%, even after 4 h under the irradiation of visible light; and (3) its antifungal activity included the effect of hydroxyl radicals generated by the photocatalysis of TiO2. The antifungal mechanism was attributed to the action of a large amount of positive charges on the structure of the hybrid film, which interacted with the negative charges from the cell and finally resulted in the inactivation of B. maydis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A 2D lamellar supermolecular complex [Cu(C6H4NO2)2 · H2O] was synthesized and characterized by elementary analysis, infrared spectrum, ultraviolet spectrum, thermogravimetry analysis and crystal X-ray diffraction analysis. The complex belongs to the orthorhombic system, Pbca space group, with a = 1.2797(8), b = 1.2944(8), c = 1.4962(9) nm, Z = 8, V = 2.478(3) nm3, D c = 1.746 g cm−3, μ = 1.784 mm−1, F(000) = 1320, R 1 = 0.0267, wR 2 = 0.0762, GOOF = 1.015, which consists of a Cu(II) ion, two 2-Picolinic acid and a coordinated water molecule. The 5-coordinated geometry of the Cu cation is a distorted tetragonal-pyramidal configuration. The 1D chain structure is formed through hydrogen bonds O(w)-H…O between single cells, and the 2D lamellar supermolecular system is formed through the non-classical hydrogen bonds C-H…O between various chains. The complex displays a distinct absorption band (λmax = 648 nm) in aqueous solution. The electrochemical behavior shows a quasi-reversible course. (CCDC: 750880)

A novel multi-functionalized cyclometalating ligand (H L ) and its two neutral-charged Pt(II) complexes, i.e., [( L )PtCl] ( C1 ) and [( L )Pt(C CC 6 H 5 )] ( C2 ) (H L = 4-{ p -[N-(4-(9-carbazole))butyl-N-phenyl]anilino}-6-phenyl-2,2′-bipyridine), have been successfully synthesized and verified by 1 H NMR, 13 C NMR, elemental analysis and/or X-ray crystallography. The introduction of the electron-donating arylamino unit at the 4-position of the electron-withdrawing 6-phenyl-2,2′-bipyridine ligand forms the D–A system, resulting in the enhanced 1 MLCT bands in the absorption spectra and intense orange emissions in the PL spectra of C1 and C2 . The carbazole units grafted through alkyl chain in H L , C1 and C2 electrochemically trigger the efficient cross-linking reaction to form polymer films, which have been characterized by AC impedance, SEM and spectroelectrochemistry. Each of the poly-H L and poly- C1 films exhibits reversible oxidation with significant color change having a high contrast ratio (81.8% for poly-H L film and 67.3% for poly- C1 film), a reasonable coloration response time (6.3 s for poly-H L film and 3.1 s for poly- C1 film) and a comparable coloration efficiency (158 C −1 cm 2 for poly-H L film and 132 C −1 cm 2 for poly- C1 film) that can be switched by modulation of the applied potential.

Two neutral-charged Pt(II) complexes, i.e., [(PBC)PtCl2] (5) and [(PBC)Pt(C ≡ CC6H5)2] (6) (PBC = N-[4-(9-carbazole)butyl]-2-(2-pyridyl)benzimidazole) have been synthesized and verified by 1H NMR and X-ray crystallography. In each of them, the coordinate geometry of Pt atom is a distorted square planar configuration with bond distances and angles in the normal range. Complex 6 shows an intense metal-to-ligand charge transfer (1MLCT) (dπ(Pt) → π*(L)) transition at 412 nm in the UV-Vis absorption spectrum and a strong phosphorescence at 593 nm in CH2Cl2 solution at ambient temperature. By selective optical-stimulation at 320 nm, an incomplete intramolecular energy transfer process from the carbazole unit to the [(PB)Pt(C ≡ CC6H5)2] center results in unbalanced dual-emissive bands of a quenched carbazole-based luminescence in deep blue region and an orange 3MLCT emission with increasing intensity. The introduction of carbazole unit also triggers the electropolymerization of ligand PBC and complexes 5 and 6. The as-formed polymer film from complex 5 has good conductivity, stability and clear anodic coloration effect.

A novel niobium fluorophosphate (NH4)2(Nb3P4O19F3)(H2en)2·H2O (1) has been synthesized by two-step hydrothermal method and characterized by elemental analyses, IR spectra, EDS analysis, PXRD, TG analysis and single-crystal X-ray diffraction. Compound 1 contains a novel two-dimensional 4.8-net layer constructed from the strict alternation of 4-connected NbO5F octahedra and 3-connected PO4 tetrahedra. 1 represents the first niobium fluorophosphate with the Nb/P ratio of 3/4. Furthermore, the ion-exchange and fluorescent properties of 1 have been studied.

A functionalized complex [Ru(L)2](PF6)2 {L = 4′-[4-(diphenylamino)phenyl)]-2,2′:6′,2″-terpyridine} was synthesized and characterized by 1H NMR, 13C NMR and elemental analyses. Its oxidative electropolymerization was conducted by continuous cycling of the working electrode potential from 0 to 1.8 V in 0.1 mol L−1 Bu4NClO4/CH3CN solution containing 5.0 × 10−4 mol L−1 monomer. The red hybrid polymer film, characterized by X-ray photoelectron spectroscopy (XPS), exhibited a non-diffusional charge transfer behaviour for Ru(III)/Ru(II) couple and an irreversible redox process of triphenylamine moiety on the Pt working electrode, as well as high stability in monomer-free electrolytic solution. The film thickness was easily tuned by controlling the number of potential sweeping cycle, and the AC impedance of as-formed film increased with cycling number. Morphological characterization of the film on indium tin oxide (ITO) was provided by scan electron microscopy (SEM) and atomic force microscopy (AFM). The donor–acceptor (D–A) polymer film on ITO showed a broad and red-shifted 1MLCT wave in the UV–vis spectrum and a clearly electrochromic behaviour from red to black in the spectroelectrochemical study.

Two novel metal-fluorides [H2N(C2H4)2NH2][NbOF5](1) and [H2N(C2H4)2NH2][TaF7](2) have been obtained by a two-step hydrothermal method and characterized by elemental analysis, IR, PXRD, EDS, TG analysis and single-crystal X-ray diffraction. X-ray diffraction reveals that both compounds exhibit the supramolecular architectures through the electrostatic interactions and hydrogen bonding interactions between protonated piperazine and anions. In the [NbOF5]2− of compound 1, the Nb atom moves from the center of the octahedron toward the oxide atom to form a short Nb=O bond and long terminal Nb–F bond. In compound 2, the Ta atom can be described as a pentagonal bipyramidal geometry coordinated by seven fluorine atoms. Furthermore, the UV spectra in solid state of compounds 1 and 2 have also been discussed, which shows both of them have strong absorption bands.

A novel Pt(II) complex [(L)PtCl] (HL = 4-{4p-[N-(4-(9-carbazole))butyl-N-phenyl] aniline}-6-phenyl-2,2'-bipyridine) has been synthesized and verified by H-1 NMR, elemental analysis and X-ray crystallography. The crystal (C44H35N4ClPt, M-r = 850.30) belongs to monoclinic system, space group P2(1)/c, with a = 21.864(6), b = 9.306 (3), c = 17.240(5) angstrom, beta = 96.483(6)degrees, Z = 4, V = 3485.3(16) angstrom(3), D-C = 1.620 g/cm(3), mu(Mo-K alpha) = 4.141 mm(-1), F(000) = 1688, R-1 = 0.0591, wR(2) = 0.0976. The coordinate geometry of the Pt atom is a distorted square planar configuration. The complex molecules are stacked by a weak pi-pi interaction in a head-to-tail fashion along the b axis to form 1D chain and the alternating 10 chains are packed to form the 2D lamellar system. The complex shows an intense metal-to-ligand charge transfer ((MLCT)-M-1) (d pi(Pt) -> pi*(L)) transitions (epsilon similar to 2 x 10(4) dm(3) mol(-1) cm(-1)) at 448 nm in the UV-Vis absorption spectrum and a strong phosphorescence at 592 nm in CH2Cl2 solution at room temperature. An intramolecular energy transfer process from the carbazole unit to the arylamine-modified (C boolean AND N boolean AND N)PtCl] emissive center exists in the complex. (C) 2010 Elsevier B.V. All rights reserved.

Using samples of A-share listed non-financial companies of 2015, This paper summarizes the research methods of inefficient investment and an effective method is chosen to measure the listed companies in China. The research in this paper shows that: China's listed companies generally exist inefficient investment and there are more companies with less investment, but the scale of inefficient investment is lager in overinvestment. In addition, this paper also provides some suggestions on how to reduce inefficient investment.

Four cyclometalated Pt(II) complexes, i.e., [(L2)PtCl] (1b), [(L3)PtCl] (1c), [(L2)PtC CC6H5] (2b) and [(L3)PtC CC6H5] (2c) (HL2 = 4-[p-(N-butyl-N-phenyl)anilino]-6-phenyl-2,2′-bipyridine and HL3 = 4-[p-(N,N′-dibutyl-N′-phenyl)phenylene-diamino]-phenyl-6-phenyl-2,2′-bipyridine), have been synthesized and verified by 1H NMR, 13C NMR and X-ray crystallography. Unlike previously reported complexes [(L1)PtCl] (1a) and [(L1)PtC CC6H5] (2a) (HL1 = 4,6-diphenyl-2,2′-bipyridine), intense and continuous absorption bands in the region of 300–500 nm with strong metal-to-ligand charge transfer (1MLCT) (dπ(Pt) → π∗(L)) transitions (e ∼ 2 × 104 dm3 mol−1 cm−1) at 449–467 nm were observed in the UV–Vis absorption spectra of complexes 1b, 1c, 2b and 2c. Meanwhile, with the introduction of electron-donating arylamino groups in the ligands of 1a and 2a, complexes 1b and 2b display stronger phosphorescence in CH2Cl2 solutions at room temperature with bathochromically shifted emission maxima at 595 and 600 nm, relatively higher quantum yields of 0.11 and 0.26, and much longer lifetimes of 8.4 and 4.5 μs, respectively. An electrochromic film of 1b-based polymer was obtained on Pt or ITO electrode surface, which suggests an efficient oxidative polymerization behavior. An orange multilayer organic light-emitting diode with 1b as phosphorescent dopant was fabricated, achieving a maximum current efficiency of 11.3 cd A−1 and a maximum external efficiency of 5.7%. The luminescent properties of complexes 1c and 2c are dependent on pH value and solvent polarity, which is attributed to the protonation of arylamino units in the C^N^N cyclometalating ligands.

A new 12-connected topological open-framework copper borovanadate NNU-6 with a unique B/V ratio (20/12) and a –B3O7(OH)–Na(μ-OH)[B(OH)2]–B3O7(OH)– connection mode has been hydrothermally obtained and characterized. It not only features the first 3-D copper(II) borovanadate which possesses the largest ratio of TM2+ and borovanadate anion, but also displays highly catalytic activities for the oxidation of benzyl-alkanes.

A cyclometalated Pt(II) acetylide derivative bearing a bis(arylamine) donor (D) and a terpyridine (TPY) receptor (A) was successfully synthesized and characterized. This three-component D-π-A system displays an intense low-energy absorption band at λmax = 470 nm, resulting from overlapping the dπ(Pt) → π*(C^N^N) metal-to-ligand charge transfer and π(C≡C-Ar) → π*(C^N^N) ligand-to-ligand charge transfer transitions with the π(bis(arylamine)) → π*(C^N^N) intraligand charge transfer transition. Upon protonation of the bis(arylamine) donor, a strong emission from the phosphorescence Pt(II) complex unit is recovered at λmax = 580 nm. With introduction of the TPY receptor, this complex possesses quite high affinity for Zn(2+) (Ka = 6.86 × 10(9) mol(-2)·dm(6)) to form the heterotrinuclear Pt-Zn-Pt complex in CH2Cl2 solution. Though this coordination effect is seriously inhibited by protons in acidic medium, the 2.4-fold luminescence intensity enhancement is obtained yet, strongly suggesting the presence of the intramolecular energy transfer process from the Zn(II)-TPY complex core to the phosphorescence Pt(II) complex units at two ends. The H(+)-triggered and Zn(2+)-enhanced luminescence can be reversibly switched on and off upon successive additions of H(+) and OH(-). Furthermore, this complex displays an unexpected Zn(2+)-selective luminescence enhancement effect in acidic solution.

Three bidentate ligands, 4-phenyl-2-(2-pyridyl)-quinoline (ppq), 6-(carbazol-9-yl)-4-phenyl-2-(2-pyridyl)-quinoline (cpq) and 6-diphenylamino-4-phenyl-2-(2-pyridyl)-quinoline (dpq) and their zinc(II) complexes, have been designed and synthesized. The crystal structure of [Zn(ppq)2Cl]PF6 shows that the central zinc atom is coordinated with one chloride and four nitrogen atoms from two ligands. The introduction of an electron-donating substituent such as carbazole or an aromatic amine group at the 6-position of the quinoline moiety can generate colored tunable Zn complexes, and the photoluminescence (PL) wavelength was modulated from 418 nm for [Zn(ppq)2Cl]PF6 to 591 nm for [Zn(cpq)2Cl]PF6 and 638 nm for [Zn(dpq)2Cl]PF6 in CH2Cl2 solution. The electroluminescence spectrum of [Zn(dpq)2Cl]PF6 exhibits pure red light emission with the Commission Internationale de L’Eclairage (CIE) coordinates (0.63, 0.36) and a maximum at 648 nm.