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A new iridium(iii) complex containing a coumarin derivative as the cyclometalated ligand (L) and a carbazole-functionalized β-diketonate (Cz-acac-allyl) as the ancillary ligand, namely, Ir(iii) bis(3-(pyridin-2-yl)coumarinato-N,C(4))(1-(9-butyl-9H-carbazol-3-yl)hept-6-ene-1,3-dionato-O,O) [Ir(L)2(Cz-acac-allyl)], was firstly synthesized as the emissive iridium(iii) complex. Then three new phosphorescent polyhedral oligomeric silsesquioxane (POSS) materials, consisting of the emissive Ir(iii) complex and carbazole moieties covalently attached to a polyhedral oligomeric silsesquioxane (POSS) core were successfully synthesized by hydrosilylation reaction in the presence of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane (Pt-dvs) as the catalyst. These phosphorescent POSS materials offer many advantages including amorphous properties, good thermal stabilities, and good solubility in common solvents, and high purity via column chromatography. The photoluminescence spectra of the POSS materials in solution and in the solid state indicate a reduction in the degrees of interactions among the Ir(iii) complex units and concentration quenching due to the bulky POSS core. Solution processed light-emitting devices based on these phosphorescent POSS materials exhibit a maximum external quantum efficiency (EQE) of 9.77%.

Three new organic bipolar molecules containing phenothiazine and phenanthoimidazole moieties, 10-butyl-3-(phenanthroimidazol-2-yl)phenothiazine (PI-PTZ), 10-butyl-3-((4-(tert-butyl)phenyl)phenanthroimidazol-2-yl)phenothiazine (PPI-PTZ) and 10-butyl-3,7-bis((4-(tert-butyl)phenyl)phenanthroimidazol-2-yl)phenothiazine (PPI-PTZ-PPI), were successfully synthesized for organic light-emitting devices. Their thermal stabilities, photophysical and electrochemical properties were investigated systematically. These compounds exhibited strong blue or blue-green emissions with photoluminescence quantum efficiency (Φf) of 41.48 %, 40.51 % and 61.52 % in chloroform solutions, while their Φf in the solid thin films decreased to 37.53 %, 34.05 % and 47.77 %, respectively. Furthermore, the vacuum-processed doped devices based on these compounds were fabricated, in which the devices based on the compound PPI-PTZ-PPI exhibited the best electroluminescence performance with a maximum brightness of 30,180 cd/m2, a maximum current efficiency of 10.65 cd/A and a maximum external quantum efficiency (EQE) of 4.0 %.

Three new asymmetric 9,9′-bifluorenylidene-based derivatives, 2,7-dibutoxyl-3′,6′-bis(5-methylenemalononitrile-3-octylthiophen-2-yl)-9,9′-bifluorenylidene (BF-TDCN2), 2,7-dibutoxyl-3′,6′-bis(5-(methylene-indene-1,3-dione)-3-octylthiophen-2-yl)-9,9′-bifluorenylidene (BF-TID2) and 2,7-dibutoxyl-3′,6′-bis(5-(2-methylene-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile)-3-octylthiophen-2-yl)-9,9′-bifluorenylidene (BF-TDCI2), were successfully synthesized by grafting different electron-withdrawing groups (malononitrile (DCN), 1H-indene-1,3(2H)-dione (ID) and 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (DCI)), which were used as the electron acceptors for organic photovoltaic cells. By changing the electron-withdrawing ability of the terminal group, the molecular energy level and band gap can be easily adjusted. The optical bandgaps of the three compounds in the thin films decreased with increasing the electron-withdrawing ability of the terminal group. Besides, the lateral chains of alkoxy groups located at the asymmetric end also play a certain influence on the solubility, molecular aggregation and the miscibility with polymer donor. Among these electron acceptors, the photovoltaic cell fabricated PBDB-T:BF-TDCI2 exhibited a maximum power conversion efficiency of 4.85% with an open-circuit voltage of 0.88 V and a low energy loss of 0.62 eV. By investigating different processing processes, the results showed that the power conversion efficiency can be improved by 20% with simple solvent annealing treatment. Through further study on the morphology and photophysical properties of the active layers, it was found that the processed device had better phase separation size and morphology, which was favorable to enhancing the intermolecular interaction, thus improving exciton separation and charge transfer in the active layer.

Three new coumarin derivatives containing aromatic-imidazole unit (i.e., benzo[d]imidazole, phenanthro[9,10-d]imidazole and pyreno[4,5-d]imidazole), 3-(1-phenyl-1H-benzo[d]imidazole-2-yl)-7-(diethylamino)coumarin (BI–C), 3-(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d]imidazole-2-yl)-7-(diethylamino)coumarin (PI–C) and 3-(9-(4-(tert-butyl)phenyl)-9H-pyreno[4,5-d]imidazole-10-yl)-7-(diethylamino)coumarin (PyI-C), were successfully prepared for organic light-emitting devices. These compounds show good thermal properties and strong emissions from greenish-blue to green lights owing to the extended π-conjugation of the rigid polyaromatic imidazole skeleton, and have high photoluminescence quantum efficiency of 94%, 97% and 98% in chloroform solutions. Among these compounds, the doped organic light-emitting device fabricated from the compound PI-C exhibited the maximum luminous efficiency of 6.07 cd/A and maximum EQE of 2.78%.

Two isoquinoline-nucleated polycyclic aromatic compounds, 4,5-diphenyl-7H-dibenzo[de,g]quinolin-7-one (A) and 3,4-diphenyl-6H-phenanthro[3,4,5-defg]quinolin-6-one (B), were synthesized in high yields through three-component reaction of phenanthrene diketone or pyrene diketone, ammonium acetate and 1,2-diphenylethyne in one-pot. Their structures, thermal stabilities, photophysical properties and energy levels are investigated systematically. Both compounds emit very weak fluorescence in acetone, but their luminescence intensity increased significantly when the water content reaches 50% for A and 40% for B, exhibiting aggregation-induced emission (AIE) characteristics, and showing that the AIE effect of the compound A is stronger than that of the compound B. The vacuum-processed doped devices based on the compound B showed green emission with a maximum brightness of 2162 cd/m2, a maximum current efficiency of 2.97 cd/A and a maximum external quantum efficiency (EQE) of 2.23%.

Two new iridium(III) complexes containing the coumarin derivatives as cyclometalated ligands (L) and the carrier transporting group-functionalized dibenzoylmethane as ancillary ligands have been successfully synthesized and characterized. The X-ray crystal structure analyses of the free ligands and the complex containing a carbazole-functionalized dibenzoylmethane as ancillary ligand were described. The photophysical properties of the Ir(III) complexes were examined via ultraviolet-visible, photoluminescence spectroscopic spectra. The good thermal stability of the Ir(III) complexes was demonstrated by the thermogravimetric analysis. The doped light-emitting devices using the Ir(III) complexes as dopants were fabricated. The devices based on the complex containing a carbazole-functionalized dibenzoylmethane as ancillary ligand possess better performance as compared with the devices fabricated by the complex containing a 1,3,4-oxadiazole-functionalized dibenzoylmethane as ancillary ligand. The devices based on the former Ir(III) complex with a 15 wt% doping concentration exhibit a maximum efficiency of 13.8 cd/A and a maximum brightness of 4955.7 cd/m2.

A new inorganic–organic hybrid material based on polyhedral oligomeric silsesquioxane (POSS) capped with carbazolyl substituents, octakis[3-(carbazol-9-yl)propyldimethylsiloxy]-silsesquioxane (POSS-8Cz), was successfully synthesized and characterized. The X-ray crystal structure of POSS-8Cz were described. The photophysical properties of POSS-8Cz were investigated by using UV–vis,photoluminescence spectroscopic analysis. The hybrid material exhibits blue emission in the solution and the solid film.The morphology and thermal stablity properties were measured by X-ray diffraction (XRD) and TG-DTA analysis.

Background Hospitalization expenses for the therapy of lung cancer are not only a direct economic burden on patients, but also the focus of medical insurance departments. Therefore, the method for classifying and analyzing lung cancer hospitalization expenses so as to predict reasonable medical cost has become an issue of common interest for both hospitals and insurance institutions. Methods A C5.0 algorithm is adopted to analyze factors influencing hospitalization expenses of 731 lung cancer patients. A C5.0 algorithm is a data mining method used to classify calculation. Results Increasing the number of input variables leads to variation in the importance of different variables, but length of stay (LOS), major therapy, and medicine cost are the three variables of greater importance. They are important factors that affect the hospitalization cost of lung cancer patients. In all three calculations, the classification accuracy rate of training and testing partition sets reached 84% and above. The classification accuracy rate reached over 95% after addition of the cost variables. Conclusion The classification rules are proven to be in accordance with actual clinical practice. The model established by the research can also be applied to other diseases in the screening and analysis of disease hospitalization costs according to selected feature variables.

Lanthanide complexes of the form Ln(DBM)3(Cz-PBM) (where Ln = Gd(III), Tb(III) and Eu(III); DBM = dibenzoylmethane and Cz-PBM = (4-(9H-carbazol-9-yl)phenyl)methyl-2-(2′-pyridyl)benzimidazole) have been successfully synthesized and characterized. The crystal structures of the Gd(III) and Tb(III) complexes were determined by single-crystal X-ray analysis. The results reveal that in the complexes the central metal ions assume a square antiprismatic geometry and are octa-coordinated by six oxygen atoms from DBM ligands and two nitrogen atoms from the Cz-PBM ligand. Under excitation with ultraviolet light, the Eu(III) complex exhibited a strong red emission, but the Tb(III) complex did not show the characteristic emissions of the Tb3+ ion. The results show that the ligands favor energy transfers to the emitting energy level of Eu3+.

This paper describes synthesis, photophysical, electrochemical characterizations of two new polyhedral oligomeric silsesquioxane (POSS)-based green-light phosphorescent materials, consisting of an emissive Ir(III) complex and carbazole moieties covalently attached to a polyhedral oligomeric silsesquioxane (POSS) core. These phosphorescent POSS materials offer many advantages including amorphous properties, good thermal stabilities, and good solubility in common solvents, and high purity via column chromatography. The photoluminescence spectra of the POSS materials in solutions and in the solid state indicate a reduction in the degrees of interactions among Ir(III) complex units and concentration quenching due to the bulky POSS core. Solution processed light-emitting devices with a configuration of ITO/PEDOT:PSS (45 nm)/CBP:POSS materials (50 nm)/TPBi (50 nm)/Liq (2 nm)/Al (150 nm) were fabricated. The devices based on these POSS materials exhibit a maximum external quantum efficiency (EQE) of 7.82% and a maximum luminance of 21 285 cd m−2.

A new iridium complex containing coumarin derivative as a cyclometalated ligand (1L) and a carbazole-functionalized β-diketonate (2L) as the ancillary ligand, namely, Ir(III)bis(3-(pyridin-2-yl)coumarinato-N,C4)(1-(9-butyl-9H-carbazol-3-yl)-4,4,4-trifluoro-butane-1,3-dionato-O,O) (Ir(1L)2(2L)), was synthesized. The crystal structure of Ir(1L)2(2L) was determined via combined wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM), which showed π–π the interactions of Ir(1L)2(2L) molecules stacking along the crystal axes. The doped light-emitting diodes using this novel Ir(1L)2(2L) complex as the phosphorescent dopant were fabricated. At a Ir(1L)2(2L) concentration of 6.0 wt%, a green-yellow emitting OLED was achieved with a maximum external quantum efficiency (EQE) of 6.11% and a maximum luminous efficiency of 22.55 cd A−1 at the current density of 6.06 mA cm−2, and a maximum luminance of 6653 cd m−2 at 10.7 V. Furthermore, two reference complexes Ir(1L)2(acac) and Ir(1L)2(TTA) were also used as emitters to fabricate OLED devices with the same device configuration. The maximum luminous efficiency of Ir(1L)2(acac) doped device was measured to be 20.04 cd A−1 at 2.15 mA cm−2 (10.0 wt%), while the doped device of Ir(1L)2(TTA) had a maximum luminous efficiency of 16.59 cd A−1 at 1.36 mA cm−2. The better performances of Ir(1L)2(2L) doped devices could be largely attributed to an improved hole-transporting property due to the introduction of the carbazole moiety.

Two new mononuclear Cu(I) complexes based on 2-(2′-pyridyl)benzimidazolyl derivative ligand containing hole-transporting carbazole (L), [Cu(L)(DPEphos)](BF4) and [Cu(L)(PPh3)2](BF4), where L = (4-(9H-carbazol-9-yl)phenyl)methyl-2-(2′-pyridyl)benzimidazole; DPEphos = bis[2-(diphenylphosphino)phenyl]ether and PPh3 = triphenylphosphine, have been synthesized and characterized on the basis of elemental analysis, 1H NMR and FT-IR spectra. The structures of the ligand L and the Cu(I) complexes were characterized by single crystal X-ray diffraction. The results reveal that in the Cu(I) complexes the central Cu(I) ions assume the irregular distorted tetrahedral geometry and are tetra-coordinated by the two nitrogen atoms from L ligand and two phosphorus atoms from ancillary ligands. The photophysical properties of the complexes were examined by using UV–vis, photoluminescence spectroscopic analysis. The complexes exhibit weak MLCT absorption bands ranging from 360 to 480 nm, and display strong orange phosphorescence in the solid states at room temperature, which is completely quenched in solutions.

Sol–gel dip-coating technique can be used to fabricate SiO2–TiO2 composite film with self-cleaning and anti-reflectance properties from low-cost SiO2 colloid solution and Ti(OC4H9)4. The physical and structural properties have been investigated by UV–visible spectrophotometer, contact angle meter, XRD, FT-IR, FESEM. UV–vis spectra and methyl orange photodegradation experiments showed that the SiO2–TiO2 composite film had high light transmittance and photocatalytic activity.

The inefficiency in the use of expensive resource such as Magnetic Resonance Imaging (MRI) will lead to long delays in patient examination which has potential influence on patients care. The main purpose of this study is to improve MRI utilization and to reduce the waiting time of patients including outpatients, inpatients and emergency patients. Scheduling rules are designed on the basis of different facility-level and multi-class examinations. As a result, assigning examination tasks according to the difference of facilities and setting fixed service time can balance examination tasks. Considering the randomness of emergency patients' arrive rate, reasonable slacking time slots performs better, compared with setting reserved time slots. Besides, setting the length of time slots equal to the length of service time can increase the number of served patients and not increase the waiting time of patients obviously.

Two new 7-N,N-diphenylamino-3-benzoheterocyclic coumarin derivatives containing electron-transporting benzotriazolyl or benzoxazolyl moiety, 3-(1-benzotriazole)-7-N,N-diphenylaminocoumarin (BTDC) and 3-(2-benzoxazole)-7-N,N-diphenylaminocoumarin (BODC), were synthesized and characterized by element analysis, 1H NMR and FT-IR spectra. The UV–vis and fluorescence spectra of these coumarin derivatives were investigated. The results show that BTDC and BODC exhibit strong blue and red emissions, respectively, under ultraviolet light excitation. The relationships between the chemical structure and the fluorescence characteristics of the 7-N,N-diphenylamino-3-benzoheterocyclic coumarin derivatives are discussed. It was found that the coumarin derivative will become a high-efficiency emitting material when an amino group is attached in 7-position of the coumarin ring, and 7- strong electron donors can improve the ability of the intramolecular charge transfer of the coumarin molecules.

The cytotoxic properties of four synthesized coumarin derivatives containing 4-bromophenyl or anthracene moieties against the human hepatocellular carcinoma cell lines (HepG-2) were investigated in vitro by use of the sulforhodamine B (SRB) assay. The four coumarin derivatives are 3-(4-bromophenyl)-benzo[5,6]coumarin (1a), 3-(4-bromophenyl)-7-(N,N-diethylamino)coumarin (1b), 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin (2a), and 3-(4-(anthracen-10-yl)phenyl)-7-(N,N-diethylamino)coumarin (2b). The preliminary results indicate that 1a, 2a, and 2b have significant cytotoxicity against HepG-2 whereas 1b has a growth-promotion effect.

We report the fabrication of high-performance broadband polymer photodetectors based on narrow bandgap conjugated polymers with an inverted device structure, where electrons and holes are collected...

Two mononuclear Cu (I) complexes based on a 2-(2-pyridyl)benzimidazolyl derivative ligand containing the hole-transporting ligand 1-[4-(9-carbazolyl)butyl]-2-(2-pyridyl)benzimidazole (L), [Cu(L)(PPh3)2](BF4) (1) and [Cu(L)(DPEphos)](BF4) (2), where DPEphos is bis[2-(diphenylphosphino)phenyl]ether, were synthesized and characterized by elemental analysis, 1H NMR and FT-IR spectra. The structure of complex 2 was determined by X-ray single crystal analysis. It was demonstrated that the central Cu (I) ion in the complex has a distorted tetrahedral geometry and is tetra-coordinated by the two nitrogen atoms from L ligand and two phosphorus atoms from DPEphos ancillary ligand. The photophysical properties of the complexes were examined by using UV–Vis, photoluminescence spectroscopic analysis. The complexes exhibit weak MLCT absorption bands at 410 and 490 nm, and display strong phosphorescence in the solid states at T = 298 K, which is completely quenched in solution.

Polymer solar cells (PSCs) made by poly(3-hexylthiophene) (P3HT) with multi-adducts fullerenes, [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM), PC61BM-bisadduct (bisPC61BM) and PC61BM-trisadduct (trisPC61BM), were reported. Electrochemistry studies indicated that PC61BM, bisPC61BM and trisPC61BM had step-up distributional lowest unoccupied molecular orbital (LUMO) energy. PSCs made by P3HT with above PC61BMs show a trend of enlarged open-circuit voltages, which is in good agreement with the energy difference between the LUMO of PC61BMs and the HOMO of P3HT. On the contrary, reduced short-circuit currents (J sc) were observed. The investigation of photo responsibility, dynamics analysis based on photo-induced absorption of composite films, P3HT:PC61BMs and n-channel thin film field-effect transistors of PC61BMs suggested that the short polaron lifetimes and low carrier mobilities were response for reduced J sc. All these results demonstrated that it was important to develop an electron acceptor which has both high carrier mobility, and good compatibility with the electron donor conjugated polymer for approaching high performance PSCs.

Novel iridium complex containing coumarin derivative as a cyclometalated ligand (L) and picolinate (pic) as the ancillary ligand, Ir(III) bis (3-(pyridin-2-yl)coumarinato N,C 4 )(picolinate) [Ir(L) 2 (pic)], was synthesized and characterized. It was demonstrated that the iridium (III) ion in Ir(L) 2 (pic) is hexacoordinated by two C atoms and two N atoms from 3-(pyridin-2-yl)coumarin ligands and one N atom and one O atom from picolinate ligand, displaying a distorted octahedral coordination geometry. The Ir(L) 2 (pic) has very strong absorption and intensive emission at 532 nm. These results show the promising future of that Ir(L) 2 (pic) in fabrication organic light-emitting diodes.

Three coumarin derivatives, 7-hydroxy-3-(2-pyridyl)coumarin (HPC), 7-(4-(5-(4-tert-butylphenyl)-1,3,4-oxadiazol-2-yl)benzyloxy)-3-(2-pyridyl)coumarin (Ox-PC), and 7-(4-(9H-carbazol-9-yl)butoxy)-3-(2-pyridyl)coumarin (Cz-PC), were synthesized and characterized by elemental analysis, 1H NMR, FT-IR, and UV–vis absorption spectra. The fluorescence behaviors of the compounds in methanol solutions and solid states were investigated. HPC exhibits weak green emission, whereas Cz-PC and Ox-PC show strong blue emissions in dilute solutions.

A new fluorescent chemosensor (A18C6-Ox) in which a monoaza-18-crown-6 is linked to a diaryl-1,3,4-oxadiazole fluorophore by a methylene spacer has been synthesized to evaluate binding interaction with the rare earth ions by means of absorption and emission spectrophotometry. Absorption spectra of A18C6-Ox showed a broad band at 289 nm and there was no significant change in the presence of Sc3+, La3+, Pr3+, Sm3+, Gd3+, Tb3+, Yb3+ and Lu3+ except for Ce3+ and Eu3+. From the emission spectral change of A18C6-Ox, interaction of the rare earth ions with A18C6-Ox is very strong. The formation of A18C6-Ox complexing with Sc3+, La3+, Pr3+, Sm3+, Gd3+, Tb3+, Yb3+ and Lu3+ leads to an increase in fluorescence intensity of A18C6-Ox, while Ce3+ and Eu3+ ions interact strongly causing fluorescence quenching of A18C6-Ox. In addition, the optimal complexation stoichiometry of the rare earth ions with A18C6-Ox was investigated by the fluorescent titration.

A new coumarin derivative, 3-(4-(anthracen-10-yl)phenyl)-7-(N,N′-diethylamino)coumarin, was synthesized and characterized by FT-IR, 1H NMR, element analysis and single crystal X-ray crystallography. The dihedral angle of coumarin ring and phenyl group is 30.83°, and the dihedral angle of phenyl group and anthracene skeleton is 76.99°. The photoluminescent (PL) and electroluminescent (EL) properties of the compound were investigated. The results show that the compound exhibits high fluorescence quantum yield (0.83), large Stokes shift and strong blue emission (466 nm). The electroluminescence devices comprised of vacuum vapor-deposited films using the compound as dopant were fabricated, showing blue emission that is identical to its photoluminescent spectrum in chloroform solutions. The electroluminescence device of indium tin oxide (ITO)/4,4′,4″-tris[2-naphthyl (phenyl)-amino]triphenylamine (2-TNATA) (5 nm)/N,N-bis-(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (NPB) (40 nm)/4,4-N,N-dicarbazole-biphenyl (CBP): dopant (1.0 wt%, 30 nm)/2-(4-biphenyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole (PBD) (30 nm)/LiF (1 nm)/Al (100 nm) gives a maximum luminous efficiency of 3.3 cd/A at the current density of 20 mA/cm2, and maximum luminance of 5070 cd/m2 at 16 V.

Two new coumarin derivatives, 7-(diethylamino)-3-(pyridin-2-yl)coumarin (DAPC) and 3-(pyridin-2-yl)-benzo[5,6]coumarin (PBC), were synthesized and characterized by elemental analysis, 1H NMR, FT-IR and UV–vis absorption spectra. Their structures were determined by X-ray crystallography single crystal analysis. The fluorescence behaviors of the compounds in dichloromethane solutions were observed. The results show that the compound DAPC exhibits high fluorescence quantum yield (0.84) and they exhibit strong blue emissions under ultraviolet light excitation. The energy levels of the HOMO and LUMO of the compounds have been calculated with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d) level.

Two new coumarin derivatives, 7-(N,N′-diethylamino)-3-(4-hydroxyphenyl)-coumarin and 7-(N,N′-diethylamino)-3-(4-bromophenyl)-coumarin, were synthesized successfully. Their structures were verified by single crystal X-ray crystallography. The UV–vis absorption and fluorescence of the compounds were discussed. The compounds exhibit strong blue emission under ultraviolet light excitation. The molecular structures, the lowest energy transitions and the UV–vis spectra of 7-(N,N′-diethylamino)-3-(4-hydroxyphenyl)-coumarin and 7-(N,N′-diethylamino)-3-(4-bromophenyl)-coumarin have been studied with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d) level.

Two new coumarin derivatives containing an electron-transporting moiety (benzotriazole), 7-N,N-diethylamino-3-(benzotriazol-1-yl)coumarin (DABTC-1) and 7-N,N-diethylamino-3-(benzotriazol-2-yl)coumarin (DABTC-2), were synthesized and characterized by element analysis, 1H NMR, FT-IR and UV–vis absorption spectra. Their structures were determined by X-ray crystallography single crystal analysis. The photoluminescent behaviors of the compounds in both solution and solid states were observed, they exhibit strong blue and blue–green emissions under ultraviolet light excitation, respectively. The energy levels of the HOMO and LUMO of the compounds have been calculated with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d) level. The electroluminescent devices with the compounds as the emitters were fabricated.

Two solvent-induced trinuclear nickel(II) clusters, [{NiL(CH(3)OH)}(2)(OAc)(2)Ni].2CH(3)OH (I) and [{NiL(C(2)H(5)OH)}(2)(OAc)(2)Ni].2C(2)H(5)OH (II), have been synthesized by the reaction of a new Salen-type bisoxime chelating ligand of 5,5'-di(N,N'-diethylamino)-2,2'-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol (H(2)L) with nickel(II) acetate tetrahydrate in different solvents. Clusters I and II were characterized by elemental analyses, IR spectra, UV-vis absorption spectra, TG-DTA and X-ray diffraction methods. In clusters I (or II), there are two ligand moieties (which provide N(2)O(2) donors), two acetate ions, two coordinated methanol (or ethanol) molecules and two crystallizing methanol (or ethanol) molecules, which result in the formation of three slightly distorted octahedral geometries around Ni(II) ions. Interestingly, nickel(II) ions in the structures of clusters I and II are all six-coordinated geometry, but clusters I and II are grown up in different solvent. Right because of this, solvent effect cause to their different crystal structures.

Three coumarin derivatives containing benzotriazole moieties, 3-(1-benzotriazolyl)-4-methyl-coumarin (BMC), 3-(1-benzotriazolyl)-4-methyl-benzo[7,8]coumarin (BMBC), and 3-(4-methyl-1-benzotriazolyl)-4-methyl-benzo[7,8]coumarin (MBMBC), were synthesized. Among them, 3-(4-methyl-1-benzotriazolyl)-4-methyl-benzo[7,8]coumarin has been structurally characterized by X-ray crystallography. The cytotoxic effect by Sulforhodamine B (SRB) assay with these compounds against the human hepatocellular carcinoma cell lines (HepG-2) was carried out in vitro. The preliminary results showed that all compounds inhibit HepG-2 growth effectively.

A novel tripodal compound, tris[2-(7-diethylamino-coumarin-3-carboxamide)ethyl]amine (tren-C), and a model compound, N-butyl-7-(diethylamino)-coumarin-3-carboxamide, were synthesized and characterized by elemental analysis, infrared and 1H NMR spectra. The structure of the model compound was characterized by single crystal X-ray crystallography. The electroluminescence devices of ITO/2-TNATA (5 nm)/NPB (40 nm)/CBP: tren-C or model compound (wt%, 30 nm)/Bu-PBD (30 nm)/LiF (1 nm)/Al (100 nm) were fabricated and characterized. The EL spectra of the devices comprising vacuum vapour-deposited films using tren-C as a dopant are similar to the PL spectrum of tren-C in chloroform solutions. At the concentration of 0.5 wt% tren-C, a blue-emitting OLED with an emission peak at 464 nm, a maximum external quantum efficiency (EQE) of 1.39% and a maximum luminous efficiency of 2 cd/A at the current density of 20 mA/cm2, and a maximum luminance of 1450 cd/m2 at 12 V are achieved.

Tris-(8-quinolinolato) aluminum (AlQ3) organic nanoparticles with an average diameter 20 nm were prepared through a reprecipitation method. The AlQ3 nanoparticles are spherical and the average particle size does not change by varying the aging time. The photoluminescent and electroluminescent properties were investigated via the AlQ3 nanoparticles and the device based on the AlQ3 nanoparticles, respectively. Blue shift of both the photoluminescence and electroluminescence spectra for the AlQ3 nanoparticles was observed. With increasing the driving bias, the maximum EL emission peak of the AlQ3 nanoparticles was shifted to longer wavelength. The maximum luminance and luminous efficiency of the AlQ3 nanoparticle-based device are about 600 cd/m2 at driving bias 16V and 0.19 cd/A at a current density of 150 mA/cm2, respectively. The obvious quantum size effect of electro-luminescence devices with the AlQ3 nanoparticles has been proved, which will open a useful route and new studying field of organic electronic devices, and the study of the fundamental process connecting both of those more conventional classes of materials, i.e., organic molecular crystals.

A novel Tb(III) complex TbL (L = tris[2-(2-carboxyphenoxy)ethyl]amine, H3L) was synthesized and characterized by means of elemental analyses, IR spectra, thermal analyses, and molar conductivity measurement. The photoluminescent properties of the complex were investigated. In addition, PVK doping Tb(III) complex was fabricated as the emissive layer by spin-coating and its electroluminescent properties were studied, in which the structure of the device was ITO (indium tin oxide)/PVK (polyvinylcarbazole)/PVK: TbL/PBD (2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole)/LiF/Al. It was indicated that pure green and narrow bandwidth emission at 545 nm from photoluminescence of TbL complex film and the organic electroluminescent device is the characteristic emission of Tb(III) ion, and the electroluminescence spectrum of the device was very similar to that of the photoluminescence of TbL complex film. The lowest triplet level of the ligand was calculated from the phosphorescence spectrum of GdL in N,N-dimethyl formamide (DMF) dilute solution determined at 77 K, and the energy transfer mechanisms in TbL complex were discussed.

A traditional hole-transporting (HT) material, 4,4′-bis[ N -(1-naphthyl)- N -phenylamino]biphenyl (NPB) was used as the host to fabricate a blue organic light-emitting diode (OLED) in which the blue dopant emitter is 2,5,8,11-tetra- t -butyl-perylene (TBP) and the another NPB layer adjusted to thinner host was also used as the HT-layer. The blue electroluminescent (EL) was proved to be originated from the narrower doped layer and the adjacent NPB HT-layer. Compared with the previous blue EL devices based on TBP dopant, the performances of the blue OLED were improved by using a thinner NPB host layer. The blue OLED shows higher efficiency and better blue color saturation, such as the device behaving a maximum efficiency of 4.6 cd/A, CIE color coordinates of x = 0.136 and y = 0.173 at a bias of 5 V, and a peak luminance of 11,500 cd/m 2 at a bias of 20 V. The operation mechanism of the blue device was also discussed.

An aromatic bridged Schiff base ligand, N,n′-bis((4,4′-diethylamino)salicylidene)-1,2-phenylenediamine (H2L3), and its trinuclear Zinc(II) complex, Zn 3 L 2 3 ( CH 3 COO ) 2 , were synthesized and characterized by means of elemental analyses, FT-IR and UV–Vis absorption spectra, and single crystal X-ray crystallography. The X-ray crystal structure of the complex reveals that the zinc ion (Zn1 or Zn1A) is coordinated by two oxygen atoms in phenolate and two nitrogen atoms in imines of the ligand and one oxygen atom of the acetate, the zinc ion (Zn2) is coordinated by four oxygen atoms in phenolate of the ligands and two oxygen atoms of the acetates. Two acetates coordinate to three zinc ions through Zn–O–C–O–Zn bridges. The complex exhibits blue-green emission as the result of the fluorescence from the intraligand emission excited state. In addition, the ground-state geometries, the lowest energy transition and the UV–Vis spectrum of the ligand have been studied with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d) level, showing that the calculation outcomes are in good agreement with experimental data.

Cerium-dicyclohexano-18-crown-6 complex, Ce-DC-18·C·6, was prepared and used to fabricate organic light-emitting diode (OLEDs) with structure of ITO (indium tin oxide)/CuPc (copper-phthalocyanine)/Ce-DC-18·C·6: CBP (4,4′-bis(9-carbazolyl)biphenyl)/Bu-PBD (2-(4-biphenylyl)-5-(4- tert -butylphenyl)-1,3,4-oxadiazole)/LiF/Al. In the device the emitter layer consists of Ce(III)-complex as a dopant and CBP as a host. Adopting this doping Ce(III)-complex film, the device exhibits ultraviolet (UV) emission at 376 nm and maximum UV radiance power 13 μW/cm 2 at 3 wt% Ce(III)-complex doped device is obtained, which has been improved by about two times in comparison with no Ce(III)-complex layer UV device. In terms of photoluminescence (PL) of Ce(III) ion and CBP film, we demonstrated that the two UV emissions should be assigned to be from electron transitions of 5d → 4f of the Ce(III) ion and of S 1 → S 0 of CBP molecule, respectively. Increasing in UV radiation at shorter UV wavelength is more valuable and interesting for solid lighting application because the shorter UV emission would much match with excitation bands of more organic or inorganic phosphors. The mechanism on the electroluminescence (EL) processes of Ce(III) ion was also discussed.

A novel coumarin derivative containing an electron-transporting moiety (benzotriazole), 3-(1H-benzotriazol-1-yl)-4-methyl-benzo[7,8]coumarin (BMBC), was synthesized and characterized by element analysis, 1H NMR, FT-IR and UV–vis absorption spectra, TG-DTA and single crystal X-ray crystallography. Crystallographic data reveal a dihedral angle of 60.4° between the benzocoumarin and benzotriazole rings, which is attributed to the spatial hindrance of a 4-positioned methyl group. The photoluminescent behaviors of BMBC doped in PMMA were discussed. The compound exhibits a strong blue emission under ultraviolet light excitation. The ground-state geometries, the lowest energy transition and the UV–vis spectrum of BMBC have been studied with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d) level, showing that the calculation outcomes are in good agreement with experimental data.

A zinc complex with a schiff base, ZnL, was synthesized and characterized by elemental analyses, infrared spectra, differential thermal analysis and thermogravimetry, in which the ligand compound is N , N ′-bis(2-hydroxy-1-naphthylidene)-3, 6-dioxa-1, 8-diaminooctane (H 2 L). The blue fluorescence of the complex in both solution and solid states was observed. The electroluminescence devices with the ZnL complex as the emitting layer were constructed, which exhibited blue emission with a peak at 455 nm and the maximum brightness of 650 cd m − 2 .

A novel coumarin derivative containing an electron-transporting moiety (benzotriazole), 3-(1-benzotriazole)-4-methyl-coumarin (BMC), was synthesized from starting substances, i.e. benzotriazole and 2-hydroxyacetophenone. The compound structure was verified by FT-IR, 1H NMR, element analysis and single crystal X-ray crystallography. Crystallographic data reveal a dihedral angle of 108° between the coumarin and benzotriazole rings, which is attributed to the spatial hindrance of a 4-positioned methyl group. The fluorescence and UV–vis absorption of BMC were discussed. The compound exhibits a strong UV emission peak at 385 nm under 360 nm excitation. The molecular structure of BMC was optimized using density functional theory (DFT) at B3LYP/6-31G(d) level, showing that the optimized geometric parameters are in good agreement with experimental data. In addition, the HOMO and LUMO levels of BMC were deduced.

A new complex of zinc with a Schiff base, zinc(N,N′-bis(salicylidene)-3, 6-dioxa-1, 8-diaminooctane monohydrate) (ZnBSO · H2O), was synthesized and characterized by means of elemental analyses, IR spectra and DTA-TG. Its structure was determined by X-ray single crystal analysis. It was demonstrated that the zinc atom is coordinated by the two oxygen atoms in phenolate and two nitrogen atoms in imine of the ligand in a slightly distorted tetrahedral geometry, while the two oxygen atoms from the oxa-alkyl chain are not coordinated to Zn(II) atom. The energy levels of the HOMO, LUMO and the electrochemical band gap were determined by cyclic voltammeter. The electroluminescent devices with the complex as the emitter showed bright blue emission with a peak at 450 nm, which is same as the fluorescence of the complex in both solution and solid states.

GdF3:Eu(3+) nanocrystals (NCs) and nanorods were synthesized by a microemulsion-mediated hydrothermal process. The structure, shape and particle size were characterized by means of x-ray diffraction (XRD) and transmission electron microscopy (TEM). The vacuum ultraviolet (VUV) spectrum of GdF3:Eu(3+) NCs shows that the Gd(3+) ion can absorb one VUV photon excited in the (6)GJ levels and relaxes through two-step energy transfer to Eu(3+), yielding two visible photons at room temperature. The visible quantum efficiency of GdF3:Eu(3+) NCs was calculated to be close to 170% by the peak intensity ratio of correlative transition emission under VUV excitation at 160 nm.

ZnS:Tb/CdS core/shell nanocrystals (NCs) were synthesized by reverse micelle method, and with a core crystal diameter of 3.0 and a 0.5 nm thick CdS shell and used as an electroluminescent material. Electroluminescent (EL) devices having a hybrid organic/inorganic multilayer structure were fabricated. Electron–hole recombination was confined at the ZnS:Tb/CdS NCs layer. Three emissions peaked at 440 nm form ZnS host, 546 nm ( 5 D 4 – 7 F 5 ) and 577 nm ( 5 D 4 – 7 F 4 ) of Tb 3+ center were observed when the hybrid EL device at a bias of 13 V. The maximum luminance of the ZnS:Tb/CdS NCs-based reached 19 cd/m 2 at 25 V.

A novel ligand, N,N′‐bis(2‐hydroxy‐1‐naphthylidene)‐3‐oxa‐1,5‐diaminopentane (H2L), and its Zn(II), Ni(II), Co(II), Cu(II) complex were synthesized. The structures of the ligand and its complexes were characterized by elemental analyses, MS (Fab), IR spectra and DTA‐TG. The results show that the molecular composition of these complexes is ML · 1/2H2O and they are tetradentate complexes, in which the metal ions are coordinated by two nitrogen atoms (‐C=N) and two oxygen atoms (Ar–OH). The fluorescence of the ligand and its complexes in different solvents and pH conditions have also been studied in detail. An enhancement of the fluorescence intensity of the ligand can be observed clearly in the presence of Zn(II), but quenching occurs for the other metal ions.

Two novel iridium organometallic compounds, Ir(III)bis(3-(pyridin-2-yl)coumarinato N,C4)(thenoyltrifluoroacetonate) and Ir(III) bis(3-(pyridin-2-yl)coumarinato N,C4)(acetylacetonate) [Ir(L)2(TTA) and Ir(L)2(acac)], were synthesized and characterized by elemental analysis, 1H NMR, FT-IR and UV–vis absorption spectra. X-ray crystallography demonstrated that Ir atom is six coordinated in Ir(III)bis(3-(pyridin-2-yl)coumarinato N,C4)(thenoyltrifluoroacetonate). Both the iridium organometallic compounds emit intense green emissions, indicating that they are useful for the fabrication of organic light-emitting diodes.

Background Hospitalization expenses for the therapy of lung cancer are not only a direct economic burden on patients, but also the focus of medical insurance departments. Therefore, the method for classifying and analyzing lung cancer hospitalization expenses so as to predict reasonable medical cost has become an issue of common interest for both hospitals and insurance institutions. Methods A C5.0 algorithm is adopted to analyze factors influencing hospitalization expenses of 731 lung cancer patients. A C5.0 algorithm is a data mining method used to classify calculation. Results Increasing the number of input variables leads to variation in the importance of different variables, but length of stay (LOS), major therapy, and medicine cost are the three variables of greater importance. They are important factors that affect the hospitalization cost of lung cancer patients. In all three calculations, the classification accuracy rate of training and testing partition sets reached 84% and above. The classification accuracy rate reached over 95% after addition of the cost variables. Conclusion The classification rules are proven to be in accordance with actual clinical practice. The model established by the research can also be applied to other diseases in the screening and analysis of disease hospitalization costs according to selected feature variables.

Two novel triethylene-glycol dicoumarin-3-carboxylates were synthesized and characterized by element analysis, (1)H NMR, FT-IR and UV-vis absorption spectra. The photoluminescent behaviors of triethylene-glycol dibenzo[5,6]coumarin-3-carboxylate doped in PMMA were discussed. These compounds exhibit strong blue emission under ultraviolet light excitation. Compared to coumarin-3-triethylene glycol diester, the absorption and emission spectra of benzo[5,6]coumarin-3-triethylene glycol diester was bathochromically shifted due to the larger conjugation of benzene moiety. These derivatives have potential possible to explore organic electroluminescent materials.

A aromatic Schiff base ligand, N, N′-bis((4, 4′-diethylamino)salicylidene)-1, 2-phenylenediamine (H2L), and its trinuclear zinc(II) complex, Zn3L2(CH3COO)2, were synthesized. The X-ray crystal structure of the complex reveals that two zinc ions show the coordination number of five and the third one has the coordination number of six. The complex exhibits blue-green emission as the result of the fluorescence from the intraligand emission excited state.

In this paper a new cyclometalated iridium(III) coumarin complex, Ir(III)bis(3-(2-benzothiazolyl)coumarinato N,C(4))(acetylacetonate) (Ir(L)2(acac)), was synthesized and characterized. X-ray crystallography demonstrated that the iridium(III) ion is hexacoordinated by two C atoms and two N atoms from 3-(2-benzothiazolyl)coumarinato ligands and two O atoms from acac ligand, displaying distorted octahedral coordination geometry. The Ir(L)2(acac) complex has good thermal stability with less than 2 % weight-reduction occurring at 300 °C, and exhibits strong reddish orange emission. The results shown that Ir(L)2(acac) is useful for fabrication organic light-emitting diodes.

Red organic light-emitting diodes using a rhenium(I) bipyridyl complex, fac-[ClRe(CO)3(trans-4-methyl-4′-(2-4-octadecyloxylphenyl)vinyl)-2,2′-bipyridine] (Re-mopvb), as an emitter were fabricated. The optimized device has a bilayer structure of indium-tin oxide∕poly(N-vinylcarbazole): 2 wt. % Re-mopvb (80 nm)∕2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (50 nm)∕LiF (1 nm)∕Al (150 nm). Although no photoluminescence from Re-mopvb in the room-temperature solution appeared due to photoinduced isomerization, a bright red electrophosphorescence from an intraligand excited state of Re-mopvb was observed at room temperature, indicating the promising future of such a class of electroluminescent materials. The maximum luminance exceeding 120cd∕m2 at 11 V and maximum efficiency of 0.75 cd∕A at 7.5 V were obtained.

Two different types of fluorescent materials containing benzothiazolyl moiety, 2-(benzothiazol-2-yl)phenol derivatives and 3-(benzothiazol-2-yl)coumarin derivatives, were synthesized synchronously using ethyl cyanoacetate, appropriate aromatic aldehyde and 2-aminothiophenol as the starting materials under the catalysis of benzoic acid by one-pot reaction. This method has the advantages of mild reaction conditions, easy processing and low waste. All synthesized compounds were characterized by elemental analysis, IR, (1)H NMR spectra. The structures of 2-(benzothiazol-2-yl)phenol derivatives, 2-(benzothiazol-2-yl)phenol (BTP) and 2-(benzothiazol-2-yl)naphthol (BTN), were determined by X-ray single crystal analysis. The UV-vis absorption and photoluminescence spectra of all synthesized compounds were investigated. The 2-(benzothiazol-2-yl)phenol derivatives exhibit bright green emissions and 3-(benzothiazol-2-yl)coumarin derivatives emit bright blue light in solutions.

The electroluminescent (EL) properties of a new coumarin derivative, 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin (APBC), were investigated. The results show that the EL devices comprised of vacuum vapor-deposited films using the derivative as dopant exhibited blue emission that is identical to the photoluminescence of the thin film. The electroluminescence device of ITO/2-TNATA (5 nm)/NPB (40 nm)/CBP : APBC (1.0 wt%, 30 nm)/PBD (30 nm)/LiF (1 nm)/Al (100 nm) gives a maximum luminous efficiency of 2.3 cd/A at the current density of 20 mA/cm(2), and maximum luminance of 5169 cd/m(2) at 16 V. The external quantum efficiency of the device is 1.85 %.