2,383 research outputs found
Interfacial chemical oxidative synthesis of multifunctional polyfluoranthene.
A novel polyfluoranthene (PFA) exhibiting strong visual fluorescence emission, a highly amplified quenching effect, and widely controllable electrical conductivity is synthesized by the direct cationic oxidative polymerization of fluoranthene in a dynamic interface between n-hexane and nitromethane containing fluoranthene and FeCl3, respectively. A full characterization of the molecular structure signifies that the PFAs have a degree of polymerization from 22-50 depending on the polymerization conditions. A polymerization mechanism at the interface of the hexane/nitromethane biphasic system is proposed. The conductivity of the PFA is tunable from 6.4 × 10-6 to 0.074 S cm-1 by doping with HCl or iodine. The conductivity can be significantly enhanced to 150 S cm-1 by heat treatment at 1100 °C in argon. A PFA-based chemosensor shows a highly selective sensitivity for Fe3+ detection which is unaffected by other common metal ions. The detection of Fe3+ likely involves the synergistic effect of well-distributed π-conjugated electrons throughout the PFA helical chains that function as both the fluorophore and the receptor units
Facile Synthesis and Versatilities of Polyanthraquinoylamine Nanofibril Bundles with Self Stability and High Carbon Yield
A facile synthesis for nanosized conducting polymers with inherent self-stability and multi-functionalities is a main challenge. Here we simply synthesize intrinsically self-stabilized nanofibril bundles of poly(1-anthraquinoylamine) (PAQ) by a template-free method. The critical polymerization parameters were studied to significantly optimize the synthesis, size, properties, and functionalities of the resulted fine nanofibrils with a diameter of ca. 30 nm and length of ~6 μm. The PAQ obtained with ammonium persulfate possesses higher polymerization yield, purer composition, higher conductivity, better melting behaviour, higher thermostability, lower burning enthalpy, and slower degradation than that with other oxidants. Furthermore, the polymer nanofibrils exhibit high self-stability, powerful redispersibility, high purity, and clean surface because of a complete avoidance of the contamination from external stabilizer. The PAQ exhibits widely controllable conductivity moving across ten orders of magnitudes from 10^-9^ to 50 S/cm, photoluminescence, lead-ion adsorbability, very high thermostability in air and extremely high char yield in nitrogen at 1000˚C. These materials would be useful as advanced materials including photoluminescent materials, highly cost-effective carbon precursors, sorbents of toxic metal ions, and cost-efficient conductive nanocomposite with low percolation threshold
Diagnosis and Treatment of Comorbidities of Tourette's Syndrome and Bipolar Disorder in A 10-Year-Old Boy
Changes in moods are one of the comorbid psychiatric manifestations that frequently occur in patients with Tourette's syndrome. The assessment of a manic episode in children with Tourette's syndrome is challenging. Furthermore, the treatment of children with comorbid mania and Tourette's syndrome has not been extensively studied. We present a 10-year-old boy who suffered from both Tourette's syndrome and mania, whose symptoms improved after using lithium and risperidone. The child was diagnosed with Tourette's syndrome at 7 years of age when he suffered from tics and experienced his first manic episode. He received monotherapy, including haloperidol, risperidone and aripiprazole, and the response was poor. When the combination of lithium and risperidone was used, the tics and mania subsided. It is important to assess individuals with Tourette's syndrome for associated bipolar disorder. The treatment of children with both disorders is a major clinical issue, and our case may serve as an example for successful treatment strategies
Structure and high-resolution thermogravimetry of liquid-crystalline copoly(p-oxybenzoate- ethylene terephthalate-p-benzamide)
Abstract: Thermotropic liquid-crystalline copoly(ester-amide)s consisting of three units of poxybenzoate (B), ethylene terephthalate (E) and p-benzamide (A) were studied by proton nuclear magnetic resonance at 200 and 400 MHz, wide-angle X-ray diffraction, and high-resolution thermogravimetry to ascertain their molecular and supermolecular structures, thermostability and kinetics parameters of thermal decomposition in both nitrogen and air. The assignments of all resonance peaks of [ 1 H]NMR spectra for the copoly(ester-amide)s are given and the characteristics of X-ray equatorial and meridional scans are discussed. Overall activation energy data of the ®rst major decomposition have been evaluated through three calculating techniques. The thermal degradation occurs in three steps in nitrogen and air. The degradation temperatures are higher than 447°C in nitrogen and 440°C in air and increase with increasing B-unit content at a ®xed A-unit content of 5 mol%. The temperatures at the ®rst maximum weight-loss rate are higher than 455°C in nitrogen and 445°C in air and also increase with an increase in B-unit content. The ®rst maximum weight-loss rates range between 11.1 and 14.5%min À1 in nitrogen and between 11.9 and 13.5%min À1 in air. The char yields at 500°C in both nitrogen and air range from 45.8 to 54.3 wt% and increase with increasing B-unit content. But the char yields at 800°C in nitrogen and air are quite irregular with the variation of copolymer composition and testing atmosphere. The activation energy and Ln (pre-exponential factor) for the ®rst major decomposition are usually higher in nitrogen than in air and increase slightly with an increase in B-unit content at a given A-unit content of 5 mol%. The activation energy, decomposition order, and Ln (pre-exponential factor) of the thermal degradation for the copoly(esteramide)s in two testing atmospheres, are situated in the ranges of 210±292 kJmol À1 , 2.0±2.8, 33±46 min À1 , respectively. The three kinetic parameters of the thermal degradation for the aromatic copoly(esteramide)s obtained by high-resolution thermogravimetry at a variable heating rate are almost the same as those by traditional thermogravimetry at constant heating rate, suggesting good applicability of kinetic methods developed for constant heating rate to the variable heating-rate method. These results indicate that the copoly(ester-amide)s exhibit high thermostability. The isothermal decomposition kinetics of the copoly(ester-amide)s at 450 and 420°C are also discussed and compared with the results obtained based on non-isothermal high-resolution thermogravimetry
Network pharmacology-based elucidation of the molecular mechanism underlying the anti-migraine effect of Asari Radix et Rhizoma
Purpose: To determine the molecular mechanism involved in the anti-migraine effect of Asari Radix et Rhizoma (ARR) using network pharmacology.
Methods: The compounds present in ARR were identified through information retrieval from literature and public databases, and were screened based on absorption, distribution, metabolism, excretion and toxicity. Target genes related to the selected compounds and migraine were identified or predicted from public databases. Hub genes in ARR against migraine were identified through analysis of interactions in overlapping genes between compounds and migraine target genes, based on STRING database. Gene enrichment analysis of overlapping genes was performed using Database for Annotation, Visualization and Integrated Discovery.
Results: A total of 138 compounds were selected as potential bioactive compounds in ARR. Target genes related to the selected compounds (611 genes) and migraine (278 genes) were obtained, including 71 overlapping genes. The hub genes in the anti-migraine effect of ARR were BDNF, IL6, COMT, APP and TNF. Gene enrichment analysis showed the top 10 biological processes or pathways involved in the mechanism of anti-migraine action of ARR. The tissue source of the overlapping genes was not limited to the brain. The results from gene enrichment analysis revealed that the effect of ARR on migraine was holistic, which is characteristic of traditional Chinese medicines.
Conclusion: Network pharmacology has been used to decipher the molecular mechanism involved in the action of ARR against migraine. The results provide a scientific basis for the clinical effect of ARR on migraine
Poly[μ2-benzene-1,3-dicarboxylÂato-κ2 O:O′-μ2-1,3-di-4-pyridylpropane-κ2 N:N′-zinc(II)]
The title compound, [Zn(C8H4O4)(C13H14N2)]n, was obtained by the hydroÂthermal reaction of Zn(OAc)2·H2O with 1,3-di-4-pyridylpropane (bpp) and isophthalic acid (H2ip). The ZnII ion is coordinated by two bpp and two ip ligands in a distorted tetraÂhedral environment. Each ligand coordinates in a bridging mode to connect ZnII ions into a three-dimensional diamondoid-type structure
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