Hierarchical NiCo2S4 Nanotube@NiCo2S4 Nanosheet Arrays on Ni Foam for High‐Performance Supercapacitors

Hierarchical NiCo₂S₄ nanotube@NiCo₂S₄ nanosheet arrays on Ni foam have been successfully synthesized. Owing to the unique hierarchical structure, enhanced capacitive performance can be attained. A specific capacitance up to 4.38 F cm^?2 is attained at 5 mA cm^?2, which is much higher than the specific capacitance values of NiCo₂O₄ nanosheet arrays, NiCo₂S₄ nanosheet arrays and NiCo₂S₄ nanotube arrays on Ni foam. The hierarchical NiCo₂S₄ nanostructure shows superior cycling stability; after 5000 cycles, the specific capacitance still maintains 3.5 F cm^?2. In addition, through the morphology and crystal structure measurement after cycling stability test, it is found that the NiCo₂S₄ electroactive materials are gradually corroded; however, the NiCo₂S₄ phase can still be well‐maintained. Our results show that hierarchical NiCo₂S₄ nanostructures are suitable electroactive materials for high performance supercapacitors.     

Underpotential Deposition Preparation of Pt‐loading AuNPs/Reduced Graphene Oxide and Its Catalytic Detection of Catechol

Ultralow Pt‐loading Au nanoparticles have been fabricated on the surface of reduced graphene oxide (RGO) by using underpotential deposition (UPD) monolayer redox replacement process. The Pt/Au/RGO modified electrode exhibits an excellent electrocatalytic activity toward catechol and hydroquinone. Under the optimized condition, the separation of peak‐to‐peak between hydroquinone and catechol is 197 mV, which is wide enough to distinguish the isomers of benzenediol. Catechol is detected by the Pt/Au/RGO/GCE with a low detection limit in the presence of hydroquinone.     

One-dimensional heterobimetallic cyanide-bridged Fe(III)–Mn(II) complex: Synthesis,crystal structure,and magnetic properties

A new cyanide-bridged heterobimetallic Fe(III)–Mn(II) complex {[MnL][FebpdBrb]} [FebpdBrb]_n· 2nH₂O has been synthesized by using pyridinecarboxamide trans-dicyanideiron as the building block. The X-ray diffraction analysis has revealed the one-dimensional infinite structure of the complex consisting of the alternating [Mn(L)]²⁺ and [Fe(bpdBrb)(CN)₂]^– units forming a cyanide-bridged cationic polymeric chain, with [Fe(bpdBrb)(CN)₂]^– as the free anions. The antiferromagnetic coupling between the neighboring Fe(III) and Mn(II) ions through the bridging cyanide group has been revealed. The magnetic coupling constant has been determined as of J =–3.17 cm^–1.     

Multiresidue analytical method of pesticides in peanut oil using low-temperature cleanup and dispersive solid phase extraction by GC-MS

A method for the determination of 33 pesticides in peanut oil by GC-MS was described. Two extraction procedures based on (i) low-temperature extraction and (ii) liquid-liquid extraction were tested for the optimization of the method. The mixture of anhydrous MgSO(4) with primary secondary amine (PSA) or with PSA and C(18) was performed as sorbents in dispersive SPE. Low temperature along with PSA and C(18) cleanup gave the best results. Pesticides were identified and quantified by GC-MS in SIM mode. The correlation coefficients, R(2), in the linear range tests were better than 0.990. The average recoveries for most pesticides (spiked at 0.02, 0.05, 0.2, and 1 mg/kg) ranged from 70 to 110%, the RSD was below 20% in most instances, and LODs varied from 0.5 to 8 mug/kg.     

Self-assembled multilayer films of poor water-soluble copper(II) complexes constructed from dipyrido[3,2-d:2′,3′-f]quinoxaline (Dpq) ligand as well as their fluorescent properties

New multilayer films were prepared by alternating adsorption of poly(sodium 4-styrenesulfonate) (PSS) and a new complex of [Cu₂(Dpq)₂(Ac)₂(H₂O)₂] (ClO₄)₂·H₂O (1) (Dpq=dipyrido[3,2-d:2′,3′-f]quinoxaline, Ac=acetate) or a related complex [Cu(Dpq)₂(H₂O)] (ClO₄)₂·H₂O (1a) by electrostatic layer-by-layer self-assembly technique, respectively. Compounds 1 and 1a have been synthesized and structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. Single-crystal X-ray analyses show that complexes 1 and 1a possess a dinuclear and a mononuclear structure, respectively, which are further extended into layered frameworks by π-π stacking and hydrogen-bonding interactions. The multilayer films were characterized by UV-vis spectroscopy, fluorescence spectroscopy, small-angle X-ray reflectivity measurements, and atomic force microscopy (AFM) imaging. UV spectroscopy shows that the deposition process is regular and highly reproducible from layer to layer. AFM image indicates that the film surface is uniform and smooth. The fluorescent properties of the films were studied and the results showed that the forming condition of the films had great influence on their properties.     

聚苯乙烯固载化聚乙二醇苄醚的合成、相转移催化及机理研究

改进了聚苯乙烯固载化聚乙二醇苄醚的合成方法,并在正溴辛烷与固体NaI的亲核取代反应中考察了它们的相转移催化性能。结果表明,催化反应对n-C₈H₁₇Br浓度为表观1级。催化剂交联度越低,粒度越小,反应速率越大。大孔催化剂活性比凝胶催化剂高;聚乙二醇固载化后的活性比固载化前高,体系中水含量对反应速率也有影响。     

高效液相色谱法同时测定牛肉及其制品中敌草隆、绿麦隆的残留量

介绍了用高效液相色谱同时测定牛肉及其制品中脲类除草剂——敌草隆、绿麦隆残留量的方法。色谱柱为ＳｅｌｅｃｔｏｓｉｌＣ１８柱,流动相为甲醇－水（６０∶４０,Ｖ／Ｖ）,ＵＶ－２４５ｎｍ检测。最小检测量：敌草隆为０．４ｎｇ,绿麦隆为０．５ｎｇ。线性范围均为０．０５～１０ｍｇ／Ｌ。回收率：敌草隆为８７．３４％～８７．６４％,绿麦隆为８８．７８％～９１．９４％。     

β-delayed Proton Decay of 89Ru

A #-delayed proton activity with a half-life of 1.2 - 0.2 s was assigned to ⁸⁹Ru on the basis of a p-%(X) coincidence measurement in the reaction of ⁵⁸Ni (³⁶Ar, 2p3n ) using a He-jet tape transport system. The measured delayed-proton spectrum of ⁸⁹Ru and relative proton branching ratios to the low-lying states in ⁸⁸Mo were compared with statistical model calculations.     

高效液相色谱法测定蜜蜂蜂体王浆酸

建立了蜂体中10－HDA的高效液相色谱分析方法。对10－HDA的提取方法进行了研究。在选择的最佳色谱条件下,线性范围为10～1000ng,r=0．9998,回收率96．5％～99．2％,检测限为0.53μg／g。     

钢铁表面Ni-Sn-P合金镀层组成及其耐蚀性

化学镀;钢铁表面Ni-Sn-P合金镀层组成及其耐蚀性