|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Destructing surfactant network in nanoemulsions by positively charged magnetic nanorods to enhance oil-water separation显示文摘The separation of ultrafine oil droplets from wasted nanoemulsions stabilized with high concentration of surfactants is precondition for oil reuse and the safe discharge of effluent.However, the double barriers of the interfacial film and network structures formed by surfactants in nanoemulsions significantly impede the oil-water separation. To destroy these surfactant protective layers, we proposed a newly-developed polyethyleneimine micelle template approach to achieve simultaneous surface charge manipulation and morphology transformation of magnetic nanospheres to magnetic nanorods. The results revealed that positively charged magnetic nanospheres exhibited limited separation performance of nanoemulsions, with a maximum chemical oxygen demand(COD) removal of 50%, whereas magnetic nanorods achieved more than 95% COD removal in less than 30 s. The magnetic nanorods were also applicable to wasted nanoemulsions from different sources and exhibited excellent resistance to wide pH changes. Owing to their unique one-dimensional structure, the interfacial dispersion of magnetic nanorods was significantly promoted, leading to the efficient capture of surfactants and widespread destruction of both the interfacial film and network structure, which facilitated droplet merging into the oil phase. The easy-toprepare and easy-to-tune strategy in this study paves a feasible avenue to simultaneously tailor surface charge and morphology of magnetic nanoparticles, and reveals the huge potential of morphology manipulation for producing high-performance nanomaterials to be applied in complex interfacial interaction process. We believe that the newly-developed magnetic-nanorods significantly contribute to hazardous oily waste remediation and advances technology evolution toward problematic oil-pollution control. | Yongjiao Xiong Xiangfeng Huang Lexue Li Wanqi Liu Jialu Zhang Mengfan He Jia Liu Lijun Lu Kaiming Peng | 2022 | Journal of Environmental Sciences2022,34,8: | 0 |
| 2 | Li^(+)-ion bound crown ether functionalization enables dual promotion of dynamics and thermodynamics for ambient ammonia synthesis显示文摘Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous efforts devoted to electrocatalysts themselves,they still fail to tackle the above two challenges simultaneously.Herein,we employ a heterogeneous catalyst adlayer-composed of crown ethers associated with Li^(+)ions-to achieve the dual promotion of dynamics and thermodynamics for ambient ammonia synthesis.Dynamically,the bound Li^(+)ions interact with the strong quadrupole moment of nitrogen,and trigger considerable reactant flux toward the catalyst.Thermodynamically,Li^(+)associated with the oxygen of crown ether achieves a higher density of states at the Fermi level for the catalyst,enabling effortless electron transfer from the catalysts to nitrogen and thus greatly reducing the activation barrier.As expected,the proof-of-concept system achieves an ammonia yield rate of 168.5μg h^(-1)mg^(-1)and a Faradaic efficiency of 75.3%at-0.3 V vs.RHE.This system-level approach opens up pathways for tackling the two key challenges that have limited the field of ammonia synthesis. | Qiyang Cheng Sisi Liu Mengfan Wang Lifang Zhang Yanzheng He Jiajie Ni Jingru Zhang Chengwei Deng Yi Sun Tao Qian Chenglin Yan | 2023 | Journal of Energy Chemistry2023,,10: | 0 |
| 3 | Solid-Phase Enzymatic Peptide Synthesis to Produce an Antioxidant Dipeptide显示文摘Peptide bond synthesis is favorable to the production of bioactive small peptides. However, the abuse of toxic reagents remains an issue for chemical synthesis method, whereas the low product yield and purity limit the widespread use of enzymatic method. In this study, a new solid-phase enzymatic peptide synthesis(SPEPS) strategy was developed to produce an antioxidant tyrosine-alanine dipeptide(Tyr-Ala) by using recombinant carboxypeptidase Y(CPY) as the catalyst. The general SPEPS procedure involves three steps. First, the N-protected acyl donor was covalently attached to solid resin. Second,the peptide bond was condensed between the acyl donor and the nucleophile under the catalysis of CPY. Finally, one-step cleavage was performed to remove the protecting group and cleave the peptides from solid resin. Upon the optimization of reaction conditions, 77.92%(±2.723%) yield of Tyr-Ala with high product purity of 90.971%(±2.695%) was obtained.In addition, the antioxidant activity of Tyr-Ala was determined by ABTS method, indicating that the synthesized Tyr-Ala obtained by SPEPS showed a superior antioxidant capability compared with commercial glutathione. | Yuyao Shan Mengfan Wang Wei Qi Rongxin Su Zhimin He | 2019 | Transactions of Tianjin University2019,25,3: | 0 |
| 4 | Kinetically Controlled Carboxypeptidase-Catalyzed Synthesis of Novel Antioxidant Dipeptide Precursor BOC-Tyr-Ala显示文摘Recently, enzymatic peptide synthesis has drawn increasing attention due to its eco-friendly reagents and mild conditions, as compared to traditional chemical peptide synthesis. In this study, we successfully produced an important antioxidant dipeptide precursor, BOC-Tyr-Ala, via a kinetically controlled enzymatic peptide synthesis reaction, catalyzed by the recombinant carboxypeptidase Y(CPY) expressed in P. pastoris GS115. In this reaction, the enzyme activity was 95.043 U/mL, and we used t-butyloxycarbonyl-L-tyrosine-methyl ester(BOC-Tyr-OMe) as the acyl donor and L-alanine( L-Ala) was the amino donor. We optimized the reaction conditions to be: 30 °C, pH 9.5, organic phase(methanol)/aqueous phase = 1:20, BOC-Tyr-OMe 0.05 mol/L, Ala 0.5 mol/L, and a reaction time of 12 h. Under these conditions, the dipeptide yield reached 49.84%. Then, we established the kinetic model of the synthesis reaction in the form of Michaelis–Menten equation according to the concentration–time curve during the process and the transpeptidation mechanism. We calculated the apparent Michaelis constant K_m^(app) and the apparent maximum reaction rate r_(max)^(app) to be 2.9946 × 10^(-2)mol/L and 2.0406 × 10^(-2)mmol/(mL h), respectively. | Yuyao Shan Wei Qi Mengfan Wang Rongxin Su Zhimin He | 2018 | Transactions of Tianjin University2018,24,6: | 0 |
| 5 | Biomineralization-inspired copper-cystine nanoleaves capable of laccase-like catalysis for the colorimetric detection of epinephrine显示文摘Recently,many efforts have been dedicated to creating enzyme-mimicking catalysts to replace natural enzymes in practical fields.Inspired by the pathological biomineralization behaviour of L-cystine,in this study,we constructed a laccase-like catalyst through the co-assembly of L-cystine with Cu ions.Structural analysis revealed that the formed catalytic Cu-cystine nanoleaves(Cu-Cys NLs)possess a Cu(I)-Cu(II)electron transfer system similar to that in natural laccase.Reaction kinetic studies demonstrated that the catalyst follows the typical Michaelis-Menten model.Compared with natural laccase,the Cu-Cys NLs exhibit superior stability during long-term incubation under extreme pH,high-temperature or high-salt conditions.Remarkably,the Cu-Cys NLs could be easily recovered and still maintained 76%of their activity after 8 cycles.Finally,this laccase mimic was employed to develop a colorimetric method for epinephrine detection,which achieved a wider linear range(9–455μmol·L^(−1))and lower limit of detection(2.7μmol·L^(−1)).The Cu-Cys NLs also displayed excellent specificity and sensitivity towards epinephrine in a test based on urine samples. | Miao Guan Mengfan Wang Wei Qi Rongxin Su Zhimin He | 2021 | Frontiers of Chemical Science and Engineering2021,15,2: | 0 |
| 6 | Nuclear peripheral chromatin-lamin B1 interaction is required for global integrity of chromatin architecture and dynamics in human cells显示文摘The eukaryotic genome is folded into higher-order conformation accompanied with constrained dynamics for coordinated genome functions.However,the molecular machinery underlying these hierarchically organized three-dimensional(3D)chromatin architecture and dynamics remains poorly understood.Here by combining imaging and sequencing,we studied the role of lamin B1 in chromatin architecture and dynamics.We found that lamin B1 depletion leads to detachment of lamina-associated domains(LADs)from the nuclear periphery accompanied with global chromatin redistribution and decompaction.Consequently,the interchromosomal as well as inter-compartment interactions are increased,but the structure of topologically associating domains(TADs)is not affected.Using live-cell genomic loci tracking,we further proved that depletion of lamin B1 leads to increased chromatin dynamics,owing to chromatin decompaction and redistribution toward nucleoplasm.Taken together,our data suggest that lamin B1 and chromatin interactions at the nuclear periphery promote LAD maintenance,chromatin compaction,genomic compartmentalization into chromosome territories and A/B compartments and confine chromatin dynamics,supporting their crucial roles in chromatin higher-order structure and chromatin dynamics. | Lei Chang Mengfan Li Shipeng Shao Chen Li Shanshan Ai Boxin Xue Yingping Hou Yiwen Zhang Ruifeng Li Xiaoying Fan Aibin He Cheng Li Yujie Sun | 2022 | Protein & Cell2022,13,4: | 0 |
| 7 | Deciphering engineering principle of three-phase interface for advanced gas-involved electrochemical reactions显示文摘As an alternative to conventional energy conversion and storage reactions,gas-involved electrochemical reactions,including the carbon dioxide reduction reaction(CO_(2)RR),nitrogen reduction reaction(NRR)and hydrogen evolution reaction(HER),have become an emerging research direction and have gained increasing attention due to their advantages of environmental friendliness and sustainability.Various studies have been designed to accelerate sluggish kinetics but with limited results.Most of them promote the reaction by modulating the intrinsic properties of the catalyst,ignoring the synergistic effect of the reaction as a whole.Due to the introduction of gas,traditional liquid-solid two-phase reactions are no longer applicable to future research.Since gas-involved electrochemical reactions mostly occur at the junctions of gaseous reactants,liquid electrolytes and solid catalysts,the focus of future research on reaction kinetics should gradually shift to three-phase reaction interfaces.In this review,we briefly introduce the formation and constraints of the three-phase interface and propose three criteria to judge its merit,namely,the active site,mass diffusion and electron mass transfer.Subsequently,a series of modulation methods and relevant works are discussed in detail from the three improvement directions of‘exposing more active sites,promoting mass diffusion and accelerating electron transfer’.Definitively,we provide farsighted insights into the understanding and research of three-phase interfaces in the future and point out the possible development direction of future regulatory methods,hoping that this review can broaden the future applications of the three-phase interface,including but not limited to gas-involved electrochemical reactions. | Yanzheng He Sisi Liu Mengfan Wang Qiyang Cheng Tao Qian Chenglin Yan | 2023 | Journal of Energy Chemistry2023,,5: | 0 |
| 8 | Cystine-assisted accumulation of gold nanoparticles on ZnO to construct a sensitive surface-enhanced Raman spectroscopy substrate显示文摘Recently,various semiconductor/metal composites have been developed to fabricate surfaceenhanced Raman spectroscopy substrates.However,low metal loading on semiconductors is still a challenge.In this study,cystine was introduced to increase the accumulation of gold nanoparticles on zinc oxide,owing to the biomineralization_property of_cystine.Morphological analysis revealed that the obtained ZnO/Au/cystine composite not only had a higher metal loading but also formed a porous structure,which is beneficial for Raman performance.Compared with ZnO/Au,the ZnO/Au/cystine substrate displayed a 40-fold enhancement in the Raman signal and a lower limit of detection(10^(-11) mol·L^(-1))in the detection of rhodamine 6G.Moreover,the substrate has favorable homogeneity and stability.Finally,ZnO/Au/cystine displayed excellent performance toward crystal violet and methylene blue in a test based on river water samples.This study provided a promising method to fabricate sensitive semiconductor/noblemetal-based surface-enhanced Ramans spectroscopy substrates for Raman detection. | Qi Qu Chuan Zeng Jing Huang Mengfan Wang Wei Qi Zhimin He | 2023 | Frontiers of Chemical Science and Engineering2023,17,1: | 0 |