摘要:
A nanohybrid composed of Ag@Cu2O heterogeneous nanocrystals supported on N-doped reduced graphene oxide (Ag@Cu2O/N-RGO) has been synthesized by a simple wet-chemical method. The resultant composite consists of N-RGO sheets fully and homogeneously coated with a dense layer of Ag@Cu2O nanocrystals. Both Ag and N-RGO are in direct contact with Cu2O, and Ag nanoparticles with sizes of 2-5 nm are mainly deposited on the surface of Cu2O cubes (edge length of 500 nm). The electrochemical studies reveal that the ternary Ag@Cu2O/N-RGO composite exhibit significantly enhanced electrocatalytic activity for H2O2 sensing compared with either the single component (N-RGO) or two component systems (Cu2O/N-RGO and Ag/N-RGO), which is mainly due to the synergetic catalysis of the ternary system. The nonenzymatic sensor based on Ag@Cu2O/N-RGO composite shows overwhelmingly superior comprehensive performance for the H2O2 detection over the documented Ag-based sensors. More specifically, it displays a rapid response (10 s) to H2O2 over a wide linear range of 54-700 nM with a high sensitivity of 1298.3 mu A mM(-1) cm(-2) and a low detection limit of 10 nM. Moreover, the sensor also exhibits the preferable selectivity in the presence of biologically coactive compounds accompanied with long-term stability and good reproducibility. (C) 2018 Elsevier B.V. All rights reserved.
期刊:
BULLETIN OF THE AUSTRALIAN MATHEMATICAL SOCIETY,2018年97(1):80-87 ISSN:0004-9727
通讯作者:
Ponnusamy, Saminathan
作者机构:
[Chen, Shaolin] Soochow Univ, Dept Math, Suzhou 215006, Jiangsu, Peoples R China.;[Chen, Shaolin] Hengyang Normal Univ, Coll Math & Stat, Hengyang 421008, Hunan, Peoples R China.;[Ponnusamy, Saminathan] Indian Stat Inst, Chennai Ctr, Stat Math Unit, 110 Nelson Manickam Rd, Madras 600029, Tamil Nadu, India.
通讯机构:
[Ponnusamy, Saminathan] I;Indian Stat Inst, Chennai Ctr, Stat Math Unit, 110 Nelson Manickam Rd, Madras 600029, Tamil Nadu, India.
关键词:
Landau's theorem;(partial derivative)over-bar-equation;Dirichlet-type space
摘要:
Three Co(II) complexes [Co(meophtpy)(2)](ClO4)(2)center dot 2CH(3)CN (1), [Co(nh(2)phtpy)(2)](ClO4)(2)center dot 2CH(3)CN (2), [Co(ftpy)(2)](ClO4)(2)center dot 2CH(3)CN (3) and three Mn(II) complexes [Mn(nme(2)phtpy)(2)]center dot(ClO4)(2)center dot 2CH(3)CN (4), [Mn(ftpy)(2)](ClO4)(2)center dot CH3CN (5), [Mn(meophtpy)(H2O)(NO3)(2)]center dot CH3CN (6) (meophtpy, 4'-(4-methoxyphenyl)- 2,2':6', 2 ''-terpyridine; nh(2)phtpy, 4'-(4-aminophenyl)-2,2':6',2 ''-terpyridine; ftpy, 4'-(furan2-yl)-2,2':6,2 ''-terpyridine; nme(2)phtpy, 4'-(4-(N,N-dimethylamino phenyl)-2,2':6',2 ''-terpyridine) are synthesized and their structures are determined by single crystal X-ray diffraction. Crystal data for 1 are: monoclinic, space group C2/c, a = 14.4781(5) angstrom, b = 16.2221(7) angstrom, c = 21.3617(9) angstrom, and Z = 4. For 2: monoclinic, space group C2/c, a = 14.554(6) angstrom, b = 15.239(6) angstrom, c = 21.754(9) angstrom, and Z = 4. For 3: monoclinic, space group C2/c, a = 14.5285(16) angstrom, b = 15.3234(16) angstrom, c = 21.154(2) angstrom, and Z = 4. For 4: triclinic, space group P-1, a = 12.132(5) angstrom, b = 12.536(5) angstrom, c = 17.840(10) angstrom, and Z = 2. For 5: triclinic, space group P-1, a = 9.993(10) angstrom, b = 13.950(13) angstrom, c = 15.511(15) angstrom, and Z = 2. For 6: monoclinic, space group Pc, a = 12.402(7) angstrom, b = 12.919(8) angstrom, c = 7.893(5) angstrom, and Z = 2. In complexes 1-5, Co(II) or Mn(II) ions are coordinated by six N atoms from two terpyridine moieties. In complex 6 the Mn(II) atom coordinates only one terpyridine ligand. All these complexes are linked by hydrogen bonds and face-to-face pi-pi interactions into three-dimensional networks. In complexes 4-6 the available solvent areas imply their potential applications in gas adsorption or catalysis.
摘要:
Within the framework of kinetic-energy-driven superconductivity, the asymmetric doping dependence of superconductivity between the hole- and electron-doped triangular-lattice superconductors has been studied. It is shown that although the superconducting transition temperature has a dome-shaped doping dependence for both the hole- and electron-doped triangular-lattice superconductors, superconductivity appears over a wide range of doping in the hole-doped case, while it only exists in a narrow range of doping in the electron-doped case. Moreover, the maximum superconducting transition temperature around optimal doping in the electron-doped triangular-lattice superconductors is lower than that of the hole-doped counterparts. The theory also shows that the asymmetric doping dependence of superconductivity between the hole- and electron-doped cases may be a common feature for a doped Mott insulator.
通讯机构:
[Wang, Xinwen] H;Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;Hengyang Normal Univ, Hunan Prov Key Lab Intelligent Informat Proc & Ap, Hengyang 421002, Peoples R China.;Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Minist Educ, Changsha 410081, Hunan, Peoples R China.
关键词:
One-step distillation;GHZ-type states;Local unitary equivalence;X states
摘要:
Entanglement distillation plays a very important role in quantum information science. Distillation of high-purity Greenberger–Horne–Zeilinger (GHZ) states has been widely studied. We here show that a pure GHZ-type entangled state or its local unitary (LU)-equivalent state could be extracted from two copies of a particular multipartite mixed state (e.g., an X state) in a single step. Such one-step distillation schemes for LU-equivalent states are expected to shed light on mixed-state manipulation and purification, as well as establish a link between entanglement classification and distillation.
期刊:
Royal Society Open Science,2018年5(11):180957 ISSN:2054-5703
通讯作者:
Yi, Chunwang
作者机构:
[Peng, Lu; Yi, Chunwang; Peng, Shumin] Hunan Normal Univ, Key Lab Sustainable Resources Proc & Adv Mat Huna, Changsha 410081, Hunan, Peoples R China.;[Yi, Chunwang] Hunan Normal Univ, Natl & Local Joint Engn Lab New Petrochem Mat & F, Changsha 410081, Hunan, Peoples R China.;[Li, Jie] Hengyang Normal Univ, Coll Chem & Mat Sci, Hengyang 421008, Hunan, Peoples R China.;[Jiang, Feng] China Text Acad, State Key Lab Biobased Fiber Mfg Technol, Beijing 100025, Peoples R China.
通讯机构:
[Yi, Chunwang] H;Hunan Normal Univ, Key Lab Sustainable Resources Proc & Adv Mat Huna, Changsha 410081, Hunan, Peoples R China.;Hunan Normal Univ, Natl & Local Joint Engn Lab New Petrochem Mat & F, Changsha 410081, Hunan, Peoples R China.
关键词:
characteristic;cyclic dimer;melting;sublimation;transition;alpha- and beta-form
摘要:
In this work, Pd-decorated N-doped reduced graphene oxide (Pd/N-RGO) was successfully synthesized by a simple wet-chemical method without using any capping agent and stabilizer. The synthesized Pd/N-RGO composite has been carefully characterized by various techniques. The X-ray photoelectron spectra provide the evidence of successful incorporation of N into the N-RGO sheets, while the presence of Pd nanoparticles with the sizes of 5-20 nm on the N-RGO sheets was confirmed by the transmission electron microscopy. By integrating the advantages of the large surface area of N-RGO sheets and good electron transfer efficiency of Pd nanoparticles, the Pd/N-RGO-based sensor shows an improved electrocatalytic activity toward the estradiol oxidation. Therefore, the Pd/N-RGO composite can be used as an effective sensing platform for the non-enzymatic detection of estradiol. It also demonstrates that the fabricated sensor has two linear concentration ranges (0.1-2 and 2-400 mu M) and a low detection limit (1.8 nM) for the estradiol detection. Finally, the resulting sensor was successfully used to detect estradiol in some real samples and the satisfactory recoveries of 96.0-103.9% were obtained. The prepared Pd/N-RGO composite with more distinct merits including simple manufacture, preferable reproducibility and long-term stability can be a promising candidate for the advanced electrode material in sensing applications. (C) 2018 Elsevier B.V. All rights reserved.
作者机构:
[Xie, Ruihua; Zhang, Youyu; Xu, Hai; Li, Yaqian; Pang, Xiao; Li, Haitao; Zhou, Zile; Huang, Zhen] Hunan Normal Univ, Coll Chem & Chem Engn, Key Lab Chem Biol & Tradit Chinese Med Res Minist, Changsha 410081, Peoples R China.;[Gu, Biao] Hengyang Normal Univ, Coll Chem & Mat Sci, Key Lab Funct Organometall Mat Coll Hunan Prov, Hengyang 421008, Hengyang, Peoples R China.;[Xie, Ruihua; Zhang, Youyu; Xu, Hai; Li, Yaqian; Pang, Xiao; Li, Haitao; Zhou, Zile; Huang, Zhen] Hunan Normal Univ, Key Lab Chem Biol & Tradit Chinese Med Res, Coll Chem & Chem Engn, Minist Educ, Changsha 410081, Hunan, Peoples R China.;[Gu, Biao] Hengyang Normal Univ, Key Lab Funct Organometall Mat, Coll Hunan Prov, Coll Chem & Mat Sci, Hengyang 421008, Peoples R China.
通讯机构:
[Li, Haitao] H;Hunan Normal Univ, Key Lab Chem Biol & Tradit Chinese Med Res, Coll Chem & Chem Engn, Minist Educ, Changsha 410081, Hunan, Peoples R China.
摘要:
In this work, a colorimetric and ratiometric fluorescent probe, 2,3-bis(((E)-4-(diethylamino)-2-hydroxybenzylidene)amino)maleonitrile (DHM), was developed based on N2H4-induced bond cleavage. Two cyanide groups of DHM were applied to sense hydrazine (N2H4) for the first time, which was demonstrated using H-1 NMR and HRMS spectra. The specific C-CN' bond cleavage induced by N2H4 showed an excellent fluorescence ratiometric behavior and a visible colorimetric change from purple to yellow. Meanwhile, it showed a low detection limit of 58.1 nM (1.65 ppb), which is far below the safety level (10 ppb) set by the U.S. EPA. Moreover, the probe was successfully employed for the quantitative detection toward N2H4 in real water samples.
摘要:
The utilization of clean and unlimited hydrogen energy is an attractive avenue to tackle the crises of energy and environmental pollution, and exploring high-active, earth-abundant and stable electro-catalysts for the oxygen evolution reaction (OER) is critical to the practicability for electrochemical water splitting. Herein, a nanohybrid with Fe-doped CoSe2 nanoparticles embedded in N-doped bamboo-like carbon nanotubes (denoted as FCS@N-CT) is prepared through simple pyrolysis followed by the selenization employing easily available raw materials for the first time. The received FCS@N-CT shows excellent electrocatalytic comprehensive properties for OER in 1M KOH solution, comparable to and even surpassing the fresh RuO2. Specifically, it requires an overpotential of only 330 mV to deliver a current density of 10 mAcm(-2), and achieves higher current density than that of RuO2 with elevating the potential over 1.652 V vs. reversible hydrogen electrode. More strikingly, FCS@N-CT exhibits a smaller Tafel slope and much better durability than those of RuO2. The remarkable electrocatalytic performance of FCS@N-CT can be ascribed to the unique nanostructure featuring abundant active sites, the favorable conductive network for rapid charge transfer, the synergistic effect between FCS and N-CT, along with the protection of FCS by carbon layers for strong robustness under catalytic conditions. (C) 2018 Elsevier Ltd. All rights reserved.