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Two novel metal–organic coordination complexes based on L [L = 3,6-bis(imidazol-1-yl)pyridazine], which could also be called as [Ni(L)(1,3,5-H2BTC)2H2O]n 1 (1,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid) and {[Ni2(L)(2,6-PYDC)2(H2O)2]·5H2O}n 2 (2,6-H2PYDC = 2,6-pyridine dicarboxylic acid) have been formed using solvothermal method by reaction of Ni(II) salts with the L ligand in the presence of different carboxylate ligands (1,3,5-H3BTC for 1 and 2,6-H2PYDC for 2). The treatment activity of compounds 1 and 2 on the neonatal hypoxic-ischemic encephalopathy was estimated, then the relevant mechanism was discussed. Firstly, the quantity of the tumor necrosis factor-α (TNF-α) and neuron-specific enolase (NSE) in the cerebrospinal fluid was measured by enzyme linked immunosorbent assay (ELISA) detection kit. In addition to this, the expression levels of the glutamate receptor on the brain nerve cells were estimated by real time reverse transcription-polymerase chain reaction (RT-PCR).

A new type of 3D NiS/MoS2@N-doped reduced graphene oxide (NiS/MoS2@N-rGO) hybrid composite is presented and its super-capacitive performance is studied. NiS/MoS2@N-rGO hybrid is synthesized via an easy and cost-effective hydrothermal route. By combining nickel sulfide and molybdenum disulfide with N-reduced graphene oxide, the as-prepared sample demonstrates a mesoporous nanostructure that increases the accessible area of the electrolyte ions. Due to the synergistic effect in the 3D network, such NiS/MoS2@N-rGO hybrid is used as electrode and it demonstrates a highly specific capacity of 2225 F/g at a current density of 1 A/g, and a good rate of 1347.3 F/g at 10 A/g. Furthermore, we also test a full symmetric supercapacitor based on NiS/MoS2@N-rGO, which displays excellent capacitive property up to 1028 F/g at 1 A/g, with high energy and good power density up to 35.69 W h/kg and 601.8 W/kg, and good cycle stability up to 94.5% initial capacitive retention after 50,000 loops. Moreover, the symmetric supercapacitor demonstrates excellent flexibility under different bending conditions.

The conducting and optical properties of a series of indeno[1,2-b]fluorene-6,12-dione (IFD)-based molecules have been systematically studied and the influences of butyl, butylthio and dibutylamino substituents on the reorganization energies, intermolecular electronic couplings and charge-injection barriers of IFD have been discussed. The quantum-chemical calculations combined with electron-transfer theory reveal that the incorporation of sulfur-linked side chains decreases reorganization energy associated with hole transfer and optimizes intermolecular π–π stacking, which results in excellent ambipolar charge-transport properties (μh = 1.15 cm2 V−1 s−1 and μe = 0.08 cm2 V−1 s−1); in comparison, addition of dibutylamino side chains increases intermolecular steric interactions and hinders perfect intermolecular π–π stacking, which results in the weak electronic couplings and finally causes the low intrinsic hole mobility (μh = 0.01 cm2 V−1 s−1). Furthermore, electronic spectra of butyl-IFD, butylthio-IFD and dibutylamino-IFD were simulated and compared with the reported experimental data. Calculations demonstrate that IFD-based molecules possess potential for developing novel infrared and near-infrared probe materials via suitable chemical modifications.

Fe3O4 nanoparticles were synthesized by hydrothermal method with the synergy reduction of ethylene glycol (MEG) and diethylene glycol (DEG). The purity, grain size, magnetism and the microwave absorption performances of the samples can be controlled by the concentration of DEG in the precursor solution. Under the optimized condition of synthesis, the product is of highly crystallized cubic Fe3O4 and the crystallite size of Fe3O4 is about 44-60 nm with the saturation magnetization about 96 emu/g. The Fe3O4 paraffin composites exhibit excellent microwave absorption properties at the frequency range of 1-18 GHz, which are attributed to the electron transition resonance, natural resonance and polarization of Fe3O4. The minimum reflection loss of Fe3O4 synthesized under the MEG and DEG content of 3.58 mol/l and 2.10 mol/l, respectively, can reach -42 dB at a thickness of 2.1 mm. And the effective absorption bandwidth of the samples can reach 3.9 GHz (7.3~11.2 GHz) at the thickness of 2.5 mm. The result demonst...

Although there are some proposed explanations for fluorescence enhancement of metal ions, a phenomenon with wide applications in biosensors and chemosensors, current understanding of the quantum–mechanical origin of this photophysical behaviour is limited. To address this issue, we selected thymolphthalein-based probe (T) reported recently as model system, and investigated the photochemical and photophysical properties of T and T-Zn(II) complex. The geometry structures of T and its Zn(II) complex were optimized, and the experimental absorption spectrum were well reproduced through density functional theory (DFT) methods. Furthermore, the excited state intramolecular proton transfer (ESIPT) mechanisms of T were systematically investigated. The constructed potential energy surfaces (PESs) of T at ground (S0) and first exited (S1) states indicate that, after photo-excitation, the intramolecular single-proton transfer reaction occurs more readily with the H atom removing from O to neighboring N. Furthermore, thermodynamic analysis of the T-Zn(II) complex shows that mononuclear complex (C1) is the most thermodynamically stable structure, and the intramolecular single proton transfer process of C1 is thermodynamically unfavorable at the S1 state. Time-dependent DFT calculations show that the fluorescence emission is from the S1 states of the single-proton transfer tautomer of T, as predicted from Kasha’s rule, in comparison, the fluorescence emission of Zn(II) complex is from the S1 states of T-Zn(II) rather than its single-proton transfer tautomer. The inhibitor of Zn(II) on the single proton transfer reaction plays an important role on fluorescence enhancement.

Taking 4-(1,2,2-triphenylvinyl)­aniline salicylaldehyde hydrazone (A) as an example, the relationship between molecular packing and charge-transport parameters has been computed and analysed. The conducting properties of A are also predicted within the framework of hopping models., Based on first-principles calculations, the relationship between molecular packing and charge-transport parameters has been investigated and analysed in detail. It is found that the crystal packing forces in the flexible organic molecule 4-(1,2,2-triphenylvinyl)­aniline salicylaldehyde hydrazone (A) can apparently overcome the dynamic intramolecular rotations and the intramolecular steric repulsion, effectively enhancing the molecular rigidity and decreasing the internal reorganization energy. The conducting properties of A have also been simulated within the framework of hopping models, and the calculation results show that the intrinsic electron mobility in A is much higher than the corresponding intrinsic hole mobility. These theoretical investigations provide guidance for the efficient and targeted control of the molecular packing and charge-transport properties of organic small-molecule semiconductors and conjugated polymeric materials.

The electronic and charge transport properties of the derivatives based on tetracene with aryl and halogenated aryl substituents have been investigated theoretically. This kind of functionalization is demonstrated to have a significant effect to stabilize the molecular orbital, densify the molecular packing, enhance the electronic coupling, and further lead to a high mobility, though it would also cause some increases in the reorganization energy. The packing modes of FPPT and PPT crystals are analyzed in details and effective coupling projected areas are put forward to understand the intermolecular interactions. Interestingly, FPPT is found to have a well-ordered packing as well as the improved hole mobility of 4.67 cm(2) V-1 s(-1). In addition, the contributions of different frequencies of vibration to the total reorganization energies are also discussed with the normal mode analysis. This study clarifies the halogenated substituent effect on transport properties and provides the guide for molecular design of novel functional materials. (C) 2015 Elsevier B.V. All rights reserved.

We systematically studied the electronic structures and conducting properties of rubrene and its derivatives reported recently, and disscussed the influences of electron-withdrawing groups and chemical oxidation on the reorganization energies, crystal packing, electronic couplings, and charge injection barrier of rubrene. Hirshfeld surface analysis and quantum-chemical calculations revealed that the introduction of CF3 groups into rubrene decreases the H···H repulsive interaction and increases intermolecular F···H/H···F attractive interactions, which resulted in the tight packing arrangement and the increase of the electronic couplings, and finally cause the higer intrinsic hole-mobility in bis(trifluoromethyl)-dimethyl-rubrene crystal (μh = 19.2 cm2 V−1 s−1) than in rubrene crystal (μh = 15.8 cm2 V−1 s−1). In comparison, chemical oxidation reduces charge-carrier mobility of rubrene crystal by 2~4 orders of magnitude and increased the hole and electron injection barrier, which partly explains the rubrene-based field-effect transistor performance degrades upon exposure to air. Furthermore, we also discussed the influence of structural parameters of carbon nanotube (CNT) electrode on charge injection process, which suggests that the regulation of CNT diameters and increasing in thickness is an effective strategy to optimize CNT work functions and improve n-type OFET performances based on these organic materials.

Herein, we systematically studied the electronic and conducting properties of the thiophene-fused polycyclic aromatic compounds and their analogues and discussed in detail the influences of edge-core structure, heteroatom substitution, and functionalization on their field-effect transistor properties and solid-state packing motifs. It was found that the influence of edge-core structure and heteroatom substitution on the electronic properties and reorganization energies of semiconducting materials mainly originates from the variations of the frontier molecular orbital charge distributions and the steric hindrance as well as the conjugate degree of compounds. Moreover, our results also showed that the fusion of benzene rings at the longitudinal end could effectively decrease energy barrier of charge injection and reorganization energies and change the molecular arrangement from herringbone packing to π stacking, which provides a promising way to functionalize organic semiconducting molecules.

Reversed-phase high-performance liquid chromatography (RP-HPLC) method with C4 column and C18 column for analyzing β-lactoglobulin and α-lactalbumin in bovine milk was developed and the performance and characteristic of two columns were compared. Shiseido Proteonavi C4 column (250 mm×4.6 mm×5 μm) and Shiseido CAPCELL PAK SG 300 C18 column (250 mm× 4.6 mm×5 μm) were used in the experiment. Phase A was composed of 0.1% (V/V) trifluoroacetic acid (TFA) in ultrapure water and Phase B (organic phase) was composed of 0.1% TFA in acetonitrile. Gradient elution was taken. Flow rate was 1 mL˙min^(-1). The detection wavelength was 215 nm. The injection volume was 20 μL and the column temperature was 30℃. The results showed that linear relationship was good and recovery of α-lactalbumin and β-lactoglobulin was 86.12%-104.38%, C18 column had stronger ability to resist acid and more stable, and the method with C4 column had excellent sensitivities and good separation.

Herein, we calculated reorganization energies, vertical ionization energies, electron affinities, and HOMO-LUMO gaps of fused thiophenes and their derivatives, and analyzed the influence of different substituents on their electronic properties. Furthermore, we simulated the angular resolution anisotropic mobility for both electron- and hole-transport, based on quantum-chemical calculations combined with the Marcus-Hush electron-transfer theory. We showed that: 1) styrene-group substitution can effectively elevate the HOMO energy level and lower the LUMO energy level, and therefore lower both the hole- and electron-injection barriers; and 2) chemical oxidation of the thiophene ring can significantly improve the semiconductor properties of the fused oligothiophenes through a decrease of the injection barrier and an increase in the charge-transfer mobility for electrons but without lowering their hole-transfer mobilities, which suggests that it may be a promising way to convert p-type semiconductors into ambipolar or n-type semiconductor materials.

We investigated oligofuran (nF) (n=3, 4, 6) heterocyclic oligomers as p-type organic semiconductor materials, based on quantum chemistry calculations combined with the Marcus-Hush electron transfer theory. It was found that 6F single crystal, with a structure similar to that of 6T, possesses high hole-transfer mobility, which is nearly 17 times larger than that of 6T single crystal. In addtion, the ionization potential (IP) value of 6F is about 5.60 eV, that is, slightly smaller than the IP value of 6T (5.74 eV). The relatively small IP values ensure effective hole injection from the source electrode. Considering that 6T and functional oligothiophenes are active p-type semiconducting materials widely used in organic electronic devices, nFs and nF-based molecules have the potential to be developed as potential high efficiency p-type organic semiconducting materials.

Attaching electron-withdrawing substituent to organic conjugated molecules is considered as an effective method to produce n-type and ambipolar transport materials. In this work, we use density functional theory calculations to investigate the electron and hole transport properties of pentacene (PENT) derivatives after substituent and simulate the angular resolution anisotropic mobility for both electron and hole transport. Our results show that adding electron-withdrawing substituents can lower the energy level of lowest unoccupied molecular orbital (LUMO) and increase electron affinity, which are beneficial to the electron injection and ambient stability of the material. Also the LUMO electronic couplings for electron transport in these pentacene derivatives can achieve up to a hundred meV which promises good electron transport mobility, although adding electron-withdrawing groups will introduce the increase of electron transfer reorganization energy. The final results of our angular resolution anisotropic mobility simulations show that the electron mobility of these pentacene derivatives can get to several cm(2) V-1 s(-1), but it is important to control the orientation of the organic material relative to the device channel to obtain the highest electron mobility. Our investigation provide detailed information to assist in the design of n-type and ambipolar organic electronic materials with high mobility performance. (C) 2011 Wiley Periodicals, Inc. J Comput Chem 32: 3218-3225, 2011