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Xu-Hui Zhu

Publications and source records attributed to Xu-Hui Zhu.

5 recordsLinked to original sources
PubMed2006

Potential solution processible phosphorescent iridium complexes toward applications in doped light-emitting diodes: rapid syntheses and optical and morphological characterizations.

A series of carbazol-9-yl end-capped red-emitting heteroleptic iridium complexes was readily synthesized using post Suzuki coupling. The appealing solubility, photoluminescent characteristics, and morphological stability enabled the current heteroleptic iridium complexes to be highly desirable phosphorescent dopant emitters in doped light-emitting diodes for the purpose of resisting molecular aggregations in the doped emitting layers.

Journal Article↗
PubMed2006

Application of chelate phosphine oxide ligand in EuIII complex with mezzo triplet energy level, highly efficient photoluminescent, and electroluminescent performances.

The chelate phosphine oxide ligand bis(2-(diphenylphosphino)phenyl) ether oxide (DPEPO) was used as a unit neutral ligand to prepare the complex Eu(TTA)(3)(DPEPO) 1 (TTA = 2-thenoyltrifluoroacetonate). Compound 1 has a photoluminescence (PL) quantum yield of 55.3%, which is more than the twice of the PL quantum yield of Eu(TTA)(3)(TPPO)(2) (TPPO = triphenylphosphine oxide). Investigation indicated that DPEPO in 1 has the mezzo first triplet excited energy level (T(1)) between the first singlet excited energy level (S(1)) and T(1) of TTA, which may support one more additional energy transfer routines from the T(1) energy level of DPEPO to that of TTA, and consequently results in the improvement of energy transfer in the Eu(III) complex. DPEPO forms a complex with a more rigid and compact structure that can improve energy transfer between ligands and the center Eu(III) ion, support the higher saturation level by the coordinating ability of the oxygen atom in the ether moiety, and consequently enhance the PL intensity and efficiency of the corresponding Eu(III) complex. The multilayered electroluminescent (EL) device of 1 used as the red dopant exhibited an impressive brightness of 632 cd m(-2) at 25 V. The device had the excellent voltage-independent spectral stability with an emission peak at 615 nm. To the best of our knowledge, this luminescence is the brightest emission among Eu complexes with phosphine oxide ligands. The maximum external quantum yield (eta(ext)) of 2.89% and the maximum current and power efficiency of 4.58 cd A(-1) and 2.05 lm W(-1) were achieved at a low turn-on voltage of 7 V and current density of 0.021 mA cm(-2). These properties demonstrate that the chelate phosphine oxides ligand DPEPO can not only be favorable to form the rigid and compact complex structure and increase the efficiency of devices, but also reduce the ability of the formation of exciplex. DPEPO shows much better performance compared with the ordinary phosphine oxide ligand triphenylphosphine oxide.

Journal Article↗
PubMed2004

[Analysis of the distribution characteristics and drug sensitivity of infection pathogens in hematology department ward].

The objective of this study was to investigate clinical distribution characteristics and drug sensitivity of infection pathogens in hematology department wards of our hospital during recent two years. The isolation and cultivation of pathogens from samples were performed by routine methods. Drug sensitivity tests of bacteria were performed by Kirby-Bauer method. Drug sensitivity tests of fungi were performed by ATBFUNGUS Drug sensitivity strips. The results showed that 102 strains of pathogens were isolated from all detected samples. The composition ratio of Gram-positive bacteria, Gram-negative bacteria and fungi was 42.2%, 34.3%, 3.5%, respectively. 58.8% of pathogens were isolated from samples of malignant hematopathy patients. 27.5% were isolated from samples of the patients with fever of unknown origin (FUO). 51.0% of pathogens were isolated from samples of the patients who suffered from agranulocytosis or leucocytopenia. Isolated fungi were mostly sensitive to anti-fungal drugs. G+ bacteria were most sensitive to vancomycin. G- bacteria were most sensitive to imipenem. Most bacteria were resistant to multiple antibiotics. It is concluded that the infection in hematology department wards was related with many conditions, such as weakened resistance of patients, leucocytopenia or agranulocytosis, tumor loading, etc. The prompt microbiological examination and drug sensitivity tests are important to rationally select antibiotics, reduce infection incidence and mortality rate, and decrease the occurrence of drug resistant strains.

Cross Infection↗
PubMed2003

Effect of mono- versus di-ammonium cation of 2,2'-bithiophene derivatives on the structure of organic-inorganic hybrid materials based on iodo metallates.

2,2'-bithiophene derivatives, 5-ammoniumethylsulfanyl-2,2'-bithiophene (AESBT) and 5,5'-bis(ammoniumethylsulfanyl)-2,2'-bithiophene (BAESBT), have been designed for their incorporation in organic-inorganic materials based on iodometalates. Three layered compounds, (BAESBT)PbI(4), (AESBT)(4)Pb(3)I(10), and (AESBT)(3)Bi(2)I(9), have been synthesized as crystals from slowly cooled aqueous solution containing metal halide and bithiophene derivative salts. When starting from the diammonium cation, (BAESBT)PbI(4) hybrid perovskite is obtained. (BAESBT)PbI(4) adopts a triclinic cell (P1) with the lattice parameters a = 8.4741(5) A, b = 8.9255(6) A, c = 16.876(1) A, alpha = 88.328(5) degrees, beta = 81.806(4) degrees, gamma = 88.864(5) degrees, Z = 2. In the structure, PbI(4)(2)(-) perovskite sheets and diammonium cation layers alternate along c. The incorporation of the corresponding monoammonium cation (AESBT) leads to a head to tail arrangement of the molecules in the (AESBT)(4)Pb(3)I(10) hybrid, precluding the formation of the perovskite layers. (AESBT)(4)Pb(3)I(10) is orthorhombic, Pna2(1), with a = 38.333(4) A, b = 22.239(3) A, c = 8.448(2) A, Z = 4. The structure consists of corrugated layers of Pb(3)I(10)(4)(-) separated by organic layers of monoammonium cations. A similar relative situation of molecules in organic layers is observed in (AESBT)(3)Bi(2)I(9), with the inorganic sheets being built up from Bi(2)I(9)(3)(-) entities. (AESBT)(3)Bi(2)I(9) crystallizes in an orthorhombic cell (P2(1)2(1)2(1)) with a = 8.4564(6) A, b = 21.368(2) A, c = 30.747(2) A, Z = 4. In the three compounds, the molecular packings appear different, underlining the interplay between both organic and inorganic components. New packings are stabilized, as illustrated by an original mixed kappa-alpha type arrangement of the bithiophene units in (AESBT)(3)Bi(2)I(9). Furthermore, molecular interactions, especially of S.S type, appear stronger in the hybrids based on the monoammonium cations. The electrical conductivity of a (BAESBT)PbI(4) single crystal has also been investigated, revealing a semiconductive behavior with a characteristic energy of E(g) = 2.535 eV.

Journal Article↗