TY  - JOUR
A1  - Chen, Xing
A1  - Meng, Guoyun
A1  - Liao, Guanming
A1  - Rauch, Florian
A1  - He, Jiang
A1  - Friedrich, Alexandra
A1  - Marder, Todd B.
A1  - Wang, Nan
A1  - Chen, Pangkuan
A1  - Wang, Suning
A1  - Yin, Xiaodong
T1  - Highly Emissive 9-Borafluorene Derivatives: Synthesis, Photophysical Properties and Device Fabrication
JF  - Chemistry—A European Journal
N2  - A series of 9-borafluorene derivatives, functionalised with electron-donating groups, have been prepared. Some of these 9-borafluorene compounds exhibit strong yellowish emission in solution and in the solid state with relatively high quantum yields (up to 73.6 % for FMesB-Cz as a neat film). The results suggest that the highly twisted donor groups suppress charge transfer, but the intrinsic photophysical properties of the 9-borafluorene systems remain. The new compounds showed enhanced stability towards the atmosphere, and exhibited excellent thermal stability, revealing their potential for application in materials science. Organic light-emitting diode (OLED) devices were fabricated with two of the highly emissive compounds, and they exhibited strong yellow-greenish electroluminescence, with a maximum luminance intensity of >22 000 cd m\(^{-2}\). These are the first two examples of 9-borafluorene derivatives being used as light-emitting materials in OLED devices, and they have enabled us to achieve a balance between maintaining their intrinsic properties while improving their stability.
KW  - boron heterocycles
KW  - photophysics
KW  - organic light-emitting diodes
KW  - luminescence
KW  - density functional calculations
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-256738
VL  - 27
IS  - 20
ER  - 
TY  - JOUR
A1  - Chen, Wei-Hua
A1  - Lu, Guanting
A1  - Chen, Xiao
A1  - Zhao, Xing-Ming
A1  - Bork, Peer
T1  - OGEE v2: an update of the online gene essentiality database with special focus on differentially essential genes in human cancer cell lines
JF  - Nucleic Acids Research
N2  - OGEE is an Online GEne Essentiality database. To enhance our understanding of the essentiality of genes, in OGEE we collected experimentally tested essential and non-essential genes, as well as associated gene properties known to contribute to gene essentiality. We focus on large-scale experiments, and complement our data with text-mining results. We organized tested genes into data sets according to their sources, and tagged those with variable essentiality statuses across data sets as conditionally essential genes, intending to highlight the complex interplay between gene functions and environments/experimental perturbations. Developments since the last public release include increased number of species and gene essentiality data sets, inclusion of non-coding essential sequences and genes with intermediate essentiality statuses. In addition, we included 16 essentiality data sets from cancer cell lines, corresponding to 9 human cancers; with OGEE, users can easily explore the shared and differentially essential genes within and between cancer types. These genes, especially those derived from cell lines that are similar to tumor samples, could reveal the oncogenic drivers, paralogous gene expression pattern and chromosomal structure of the corresponding cancer types, and can be further screened to identify targets for cancer therapy and/or new drug development. OGEE is freely available at http://ogee.medgenius.info.
KW  - human cancer cell lines
KW  - gene essentiality database
KW  - OGEE v2
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-181334
VL  - 45
IS  - D1
ER  - 
TY  - JOUR
A1  - He, Jiangang
A1  - Di Sante, Domenico
A1  - Li, Ronghan
A1  - Chen, Xing-Qiu
A1  - Rondinelli, James M.
A1  - Franchini, Cesare
T1  - Tunable metal-insulator transition, Rashba effect and Weyl Fermions in a relativistic charge-ordered ferroelectric oxide
JF  - Nature Communications
N2  - Controllable metal–insulator transitions (MIT), Rashba–Dresselhaus (RD) spin splitting, and Weyl semimetals are promising schemes for realizing processing devices. Complex oxides are a desirable materials platform for such devices, as they host delicate and tunable charge, spin, orbital, and lattice degrees of freedoms. Here, using first-principles calculations and symmetry analysis, we identify an electric-field tunable MIT, RD effect, and Weyl semimetal in a known, charge-ordered, and polar relativistic oxide Ag2BiO3 at room temperature. Remarkably, a centrosymmetric BiO6 octahedral-breathing distortion induces a sizable spontaneous ferroelectric polarization through Bi3+/Bi5+ charge disproportionation, which stabilizes simultaneously the insulating phase. The continuous attenuation of the Bi3+/Bi5+ disproportionation obtained by applying an external electric field reduces the band gap and RD spin splitting and drives the phase transition from a ferroelectric RD insulator to a paraelectric Dirac semimetal, through a topological Weyl semimetal intermediate state. These findings suggest that Ag2BiO3 is a promising material for spin-orbitonic applications.
KW  - electronic properties and materials
KW  - ferroelectrics and multiferroics
KW  - topological matter
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227946
VL  - 9
ER  -