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861.
Chenlu Zhang Xing Li Zhongshan Chen Tao Wen Shuyi Huang Tasawar Hayat Ahmed Alsaedi Xiangke Wang 《中国科学:化学(英文版)》2018,61(3):281-293
An extremely effortless method was applied for successful synthesis of mesoporous carbonaceous materials(MCMs) using well-ordered mesoporous silica as template. Various characterizations(scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), Raman, X-ray photoelectron spectroscopy(XPS), Brunner-Emmet-Teller(BET) and Zeta potential) confirmed that MCMs had large surface area, uniform pore size distribution, and abundant oxygen-containing functional groups. The batch techniques were employed to study U(VI) adsorption on MCMs under a wide range of experiment conditions. The adsorption kinetics of U(VI) onto MCMs were well-fitted by pseudo-second-order kinetic model, indicating a chemisorption process. The excellent adsorption capacity of MCMs calculated from the Langmuir model was 293.95 mg g~(-1) at pH 4.0. The FT-IR and XPS analyses further evidenced that the binding of U(VI) onto MCMs was ascribed to the plentiful adsorption sites(–OH and –COOH groups) in the internal mesoporous structure, which could efficiently trap guest U(VI) ions. The results presented herein revealed that MCMs were ideal adsorbents in the efficient elimination of uranium or other lanthanides/actinides from aqueous solutions, which would play an important role in environmental pollution management application. 相似文献
862.
Manipulation of Molecular Aggregation States to Realize Polymorphism,AIE, MCL,and TADF in a Single Molecule 下载免费PDF全文
Dr. Bin Huang Dr. Wen‐Cheng Chen Zijing Li Dr. Jinfeng Zhang Dr. Weijun Zhao Dr. Yan Feng Prof. Ben Zhong Tang Prof. Chun‐Sing Lee 《Angewandte Chemie (International ed. in English)》2018,57(38):12473-12477
Multifunctional emitting materials are scarce and need to be further explored. Now, a newly anthraquinone derivative, 2‐(phenothiazine‐10‐yl)‐anthraquinone (PTZ‐AQ) was designed and synthesized and found to demonstrate polymorphism, multi‐color emission, aggregation‐induced emission (AIE), mechanochromic luminescence (MCL), and thermally activated delayed fluorescence (TADF) in its different solid forms. It is shown for the first time that TADF properties of a compound can be systematically tuned via its aggregation state. The optimized PTZ‐AQ crystal shows a small singlet–triplet energy splitting of 0.01 eV and exhibits red TADF with a photoluminescence quantum yield as high as 0.848. This study shows that the unique multiple functions can be integrated into one single compound through controlling the aggregation states, which provides a new strategy for the investigation and application of multifunctional organic materials. 相似文献
863.
Boosting Hydrogen Production by Anodic Oxidation of Primary Amines over a NiSe Nanorod Electrode 下载免费PDF全文
Dr. Yi Huang Xiaodan Chong Dr. Cuibo Liu Yu Liang Prof. Bin Zhang 《Angewandte Chemie (International ed. in English)》2018,57(40):13163-13166
For electrocatalytic water splitting, the sluggish anodic oxygen evolution reaction (OER) restricts the cathodic hydrogen evolution reaction (HER). Therefore, developing an alternative anodic reaction with accelerating kinetics to produce value‐added chemicals, especially coupled with HER, is of great importance. Now, a thermodynamically more favorable primary amine (?CH2?NH2) electrooxidation catalyzed by NiSe nanorod arrays in water is reported to replace OER for enhancing HER. The increased H2 production can be obtained at cathode; meanwhile, a variety of aromatic and aliphatic primary amines are selectively electrooxidized to nitriles with good yields at the anode. Mechanistic investigations suggest that NiII/NiIII may serve as the redox active species for the primary amines transformation. Hydrophobic nitrile products can readily escape from aqueous electrolyte/electrode interface, avoiding the deactivation of the catalyst and thus contributing to continuous gram‐scale synthesis. 相似文献
864.
Heavily Doped and Highly Conductive Hierarchical Nanoporous Graphene for Electrochemical Hydrogen Production 下载免费PDF全文
Linghan Chen Dr. Jiuhui Han Dr. Yoshikazu Ito Dr. Takeshi Fujita Dr. Gang Huang Kailong Hu Dr. Akihiko Hirata Dr. Kentaro Watanabe Prof. Mingwei Chen 《Angewandte Chemie (International ed. in English)》2018,57(40):13302-13307
Heavy chemical doping and high electrical conductivity are two key factors for metal‐free graphene electrocatalysts to realize superior catalytic performance toward hydrogen evolution. However, heavy chemical doping usually leads to the reduction of electrical conductivity because the catalytically active dopants give rise to additional electron scattering and hence increased electrical resistance. A hierarchical nanoporous graphene, which is comprised of heavily chemical doped domains and a highly conductive pure graphene substrate, is reported. The hierarchical nanoporous graphene can host a remarkably high concentration of N and S dopants up to 9.0 at % without sacrificing the excellent electrical conductivity of graphene. The combination of heavy chemical doping and high conductivity results in high catalytic activity toward electrochemical hydrogen production. This study has an important implication in developing multi‐functional electrocatalysts by 3D nanoarchitecture design. 相似文献
865.
Back Cover: Single‐Nanoparticle Cell Barcoding by Tunable FRET from Lanthanides to Quantum Dots (Angew. Chem. Int. Ed. 41/2018) 下载免费PDF全文
866.
867.
Peng Huang Jinlei Shi Qingwen Sun Xianping Dong Ning Zhang 《Applied biochemistry and biotechnology》2018,186(2):459-475
Lysozymes are known as ubiquitously distributed immune effectors with hydrolytic activity against peptidoglycan, the major bacterial cell wall polymer, to trigger cell lysis. In the present study, the full-length cDNA sequence of a novel sea urchin Strongylocentrotus purpuratus invertebrate-type lysozyme (sp-iLys) was synthesized according to the codon usage bias of Pichia pastoris and was cloned into a constitutive expression plasmid pPIC9K. The resulting plasmid, pPIC9K-sp-iLys, was integrated into the genome of P. pastoris strain GS115. The bioactive recombinant sp-iLys was successfully secreted into the culture broth by positive transformants. The highest lytic activity of 960 U/mL of culture supernatant was reached in fed-batch fermentation. Using chitin affinity chromatography and gel-filtration chromatography, recombinant sp-iLys was produced with a yield of 94.5 mg/L and purity of >?99%. Recombinant sp-iLys reached its peak lytic activity of 8560 U/mg at pH 6.0 and 30 °C and showed antimicrobial activities against Gram-negative bacteria (Vibrio vulnificus, Vibrio parahemolyticus, and Aeromonas hydrophila) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis). In addition, recombinant sp-iLys displayed isopeptidase activity which reached the peak at pH 7.5 and 37 °C with the presence of 0.05 M Na+. In conclusion, this report describes the heterologous expression of recombinant sp-iLys in P. pastoris on a preparative-scale, which possesses lytic activity and isopeptidase activity. This suggests that sp-iLys might play an important role in the innate immunity of S. purpuratus. 相似文献
868.
Lin-Feng You Tao Wei Qian-Wang Zheng Jun-Fang Lin Li-Qiong Guo Bing-Hua Jiang Jia-Jun Huang 《Applied biochemistry and biotechnology》2018,186(4):949-959
Taxoid 10β-O-acetyl transferase (DBAT) is a key enzyme in the biosynthesis of the famous anticancer drug paclitaxel, which catalyses the formation of baccatin III from 10-deacetylbaccatin III (10-DAB). However, the activity essential residues of the enzyme are still unknown, and the acylation mechanism from its natural substrate 10-deacetylbaccatin III and acetyl CoA to baccatin III remains unclear. In this study, the homology modelling, molecular docking, site-directed mutagenesis, and kinetic parameter determination of the enzyme were carried out. The results showed that the enzyme mutant DBATH162A resulted in complete loss of enzymatic activity, suggesting that the residue histidine at 162 was essential to DBAT activity. Residues D166 and R363 which were located in the pocket of the enzyme by homology modelling and molecular docking were also important for DBAT activity through the site-directed mutations. Furthermore, four amino acid residues including S31 and D34 from motif SXXD, D372 and G376 from motif DFGWG also played important roles on acylation. This was the first report of the elucidation of the activity essential residues of DBAT, making it possible for the further structural-based re-design of the enzyme for efficient biotransformation of baccatin III and paclitaxel. 相似文献
869.
Lujuan Liao Zhenjie Li Wei Hu Yan Huang Bu-min Liu Lisheng Wang Mian Wang Jianyi Wang 《Tetrahedron letters》2018,59(27):2683-2687
A novel H2S-responsive fluorescent probe Rh-Lyso-H2S has been designed and synthesized. The Rh-Lyso-H2S shows high sensitivity and selectivity toward H2S, with a limit of detection of 3.36?×?10?7?M. The reason is that Rh-Lyso-H2S changed from a stable non-conjugated closed-ring lactone conformation with weak fluorescence to a conjugated open-ring conformation with strong fluorescence in the presence of H2S. The Rh-Lyso-H2S has a good lysosome-targeting capacity and is used to detect lysosomal H2S in living cells, which is driven via the protonation of its basic morpholine moiety by acidic lysosomes. Rh-Lyso-H2S is triggered by H2S via removing the thiophenecarboxylate group, and the corresponding activated mechanism of Rh-Lyso-H2S toward H2S is proposed. 相似文献
870.
Bingbing Shi Zhengtao Li Yuezhou Liu Liqing Shangguan Huangtianzhi Zhu Huaqiang Ju Feihe Huang 《Tetrahedron letters》2018,59(38):3477-3480
Here we report the design and syntheses of two new triptycene-based rigid acyclic C-shaped hosts, clip[5]arenes C[5]OH and C[5]ME, and the strong host–guest complexation between C[5]OH and an electron-poor bipyridinium salt, paraquat G. The Ka value for the host–guest complex C[5]OH???G was calculated to be (1.09?±?0.36)??×??105?M?1 in acetone by using a non-linear curve-fitting method based on the UV–vis absorption titration experiments. Furthermore, based on this new host–guest recognition motif, a novel pseudopolyrotaxane-like supramolecular structure was constructed with C[5]OH threaded on polyviologen polymer VP-10. 相似文献