Investigating the Electrochemical Performance of MnFe2O4@xC Nanocomposites as Anode Materials for Sodium-Ion Batteries.

Transition metal oxides (TMOs) are important anode materials in sodium-ion batteries (SIBs) due to their high theoretical capacities, abundant resources, and cost-effectiveness. However, issues such as the low conductivity and large volume variation of TMO bulk materials during the cycling process result in poor electrochemical performance. Nanosizing and compositing with carbon materials are two effective strategies to overcome these issues. In this study, spherical MnFe2O4@xC nanocomposites composed of MnFe2O4 inner cores and tunable carbon shell thicknesses were successfully prepared and utilized as anode materials for SIBs. It was found that the property of the carbon shell plays a crucial role in tuning the electrochemical performance of MnFe2O4@xC nanocomposites and an appropriate carbon shell thickness (content) leads to the optimal battery performance. Thus, compared to MnFe2O4@1C and MnFe2O4@8C, MnFe2O4@4C nanocomposite exhibits optimal electrochemical performance by releasing a reversible specific capacity of around 308 mAh·g-1 at 0.1 A·g-1 with 93% capacity retention after 100 cycles, 250 mAh·g-1 at 1.0 A g-1 with 73% capacity retention after 300 cycles in a half cell, and around 111 mAh·g-1 at 1.0 C when coupled with a Na3V2(PO4)3 (NVP) cathode in a full SIB cell.

Bis(triethano-lamine)nickel(II) sulfate.

The title compound, [Ni(C(6)H(15)NO(3))(2)]SO(4), contains two triethano-lamine (TEA) ligands bound to an Ni(2+) metal centre, which lies on a crystallographic inversion centre, and one sulfate anion located on a twofold rotation axis such that the asymmetric unit contains one-half molecule of the cation and of the anion. The triethano-lamine ligands coordinate via each axial N atom and two of the three O atoms, while the third arm of the ligand has the hydroxyl group pointing away from the metal centre. The sulfate anions are hydrogen bonded to the coordinated hydroxyl groups and also to the free arm, forming a two-dimensional supra-molecular hydrogen-bonded network expanding parallel to (010).

Diaqua-(triethano-lamine)copper(II) sulfate monohydrate.

The asymmetric unit of the title compound, [Cu(C(6)H(15)NO(3))(H(2)O)(2)]SO(4)·H(2)O, contains a complex cation, a sulfate anion and one uncoordinated water mol-ecule. In the complex cation, the Cu(II) ion is coordinated by five O atoms (three of which are from the triethano-lamine ligand and two from coordinated water mol-ecules) and one N atom of the triethano-lamine ligand in a typical Jahn-Teller-distorted octa-hedral geometry. Classical inter-molecular O-H⋯O hydrogen bonds link the cation, the sulfate anion and the water mol-ecule into a two-dimensional network.

(µ-4,4'-Bipyridine-κN:N')bis-[triaqua-(4,4'-bipyridine-κN)(3-nitro-phthalato-κO)cobalt(II)].

The title binuclear complex, [Co(2)(C(8)H(3)NO(6))(2)(C(10)H(8)N(2))(3)(H(2)O)(6)], has been synthesized hydro-thermally from 3-nitro-phthalic acid (H(2)NPA), Co(NO(3))(2)·6H(2)O and 4,4'-bipyridine (4,4'-bipy). The mol-ecule of the complex occupies a special position on an inversion centre. The Co(II) atom has a slightly distorted octa-hedral environment formed by two N atoms from two 4,4'-bipy ligands, one carboxyl-ate O atom from NPA, and three O atoms of water mol-ecules. An extensive O-H⋯O and N-H⋯O hydrogen-bonding system links mol-ecules of the complex into a three-dimensional network.

A novel three-dimensional coordination polymer constructed from pyrazine and copper(I): poly[[copper(I)-di-mu2-pyrazine-kappa4N:N'] 3,5-dicarboxybenzenesulfonate monohydrate].

In the title metal-organic framework complex, {[Cu(C(4)H(4)N(2))(2)](C(8)H(5)O(7)S).H(2)O}(n) or {[Cu(I)(pyz)(2)](H(2)SIP).H(2)O}(n) (pyz is pyrazine and H(3)SIP is 5-sulfoisophthalic acid or 3,5-dicarboxybenzenesulfonic acid), the asymmetric unit is composed of one copper(I) center, one whole pyrazine ligand, two half pyrazine ligands lying about inversion centres, one H(2)SIP(-) anion and one lattice water molecule, wherein each Cu(I) atom is in a slightly distorted tetrahedral coordination environment completed by four pyrazine N atoms, with the Cu-N bond lengths in the range 2.017 (3)-2.061 (3) A. The structure features a three-dimensional diamondoid network with one-dimensional channels occupied by H(2)SIP(-) anions and lattice water molecules. Interestingly, the guest-water hydrogen-bonded network is also a diamondoid network, which interpenetrates the metal-pyrazine network.

Bis(µ-biphenyl-2,2'-dicarboxyl-ato)bis-[(2,2'-bipyridine)copper(II)].

The title compound, [Cu(2)(C(14)H(8)O(4))(2)(C(10)H(8)N(2))(2)], is a centrosymmetric binuclear copper(II) complex, with a Cu⋯Cu separation of 6.136 (16) Å. The Cu atom displays a cis-CuN(2)O(2) square-planar geometry, although two long (> 2.43 Å) Cu⋯O contacts complete a distorted cis-CuN(2)O(4) octa-hedron. Extensive C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network.

trans-N,N,N',N'-Tetra-kis(carboxy-meth-yl)cyclo-hexane-1,2-diammonium tetra-chloridocadmium(II) tetra-hydrate.

In the title compound, (C(14)H(24)N(2)O(8))[CdCl(4)]·4H(2)O, the Cd atom in the tetra-hedral [CdCl(4)](2-) anion lies on a twofold rotation axis, and the diprotonated organic mol-ecule, trans-N,N,N',N'-tetra-kis(carb-oxy-meth-yl)cyclo-hexane-1,2-diammon-ium, has 2 symmetry with the twofold rotation axis running through the mid-point of two C-C bonds in the cyclo-hexane unit. In the crystal structure, classical intra-molecular O-H⋯O and N-H⋯O and inter-molecular O-H⋯O, N-H⋯O, O-H⋯Cl and C-H⋯Cl hydrogen bonds are observed.

(R)-1,1'-Binaphthalene-2,2'-diyl dicinnamate.

In the title compound, C(38)H(26)O(4), two cinnamo-yloxy groups are linked in a trans fashion to the two O atoms of optically active (R)-1,10-bi-2-naphthol. The dihedral angle between the mean planes of the two naphthyl groups is 71.8 (1)°. The crystal structure contains inter-molecular C-H⋯O and C-H⋯π inter-actions.

[Case analysis and control strategy of imported malaria in Qingcheng District, Qingyuan City from 2011 to 2016].

OBJECTIVE: To understand the characteristics of imported malaria cases in Qingcheng District, Qingyuan City and explore the strategies and priorities in prevention and control, so as to provide the evidence for improving the diagnosis, treatment and management of imported malaria. METHODS: The data of imported malaria as well as the case epidemiological investigations were collected and retrospectively analyzed for the species composition, original countries, population distribution, regional distribution, onset situation, diagnosis, treatment, etc. in Qingcheng District from 2011 to 2016. RESULTS: The number of imported malaria cases was 13 from 2011 to 2016. All the patients were confirmed by laboratory, and of which, 9 patients infected with Plasmodium falciparum, 1 with P. vivax, 1 with P. ovale and 2 with mixed infections (P. vivax and P. falciparum). The yearly incidence of imported malaria presented an uptrend. The infection sources of all the patients were from African countries, and the exported labor workers and travelers for business from malaria endemic areas were the high risk population. The reported time was mainly January, February, November and December (11/13, 84.62%). All the patients were male, and the majority of them (12/13, 2.31%) were 21-60 years old. The median time from onset to seeing a doctor was 2.5 days and the median time from seeing a doctor to being diagnosed was 1.9 day. Six patients (46.15%) were diagnosed as other diseases at the first visit to a doctor, and one patient died of falciparum malaria because of delayed diagnosis. CONCLUSIONS: The incidence of overseas imported malaria presents an uptrend in Qingcheng District. It is necessary to further strengthen the professional training in medical staff to improve the diagnosis and treatment of malaria cases. It is also necessary to strengthen the multisectoral cooperation, establish the surveillance in the high risk population, etc.

A novel highly selective colorimetric sensor for aluminum (III) ion using Schiff base derivative.

A novel colorimetric sensor, 2-hydroxy naphthaldehyde isonicotinoyl hydrazone (HINH), was easily synthesized by the condensation of isoniazid and 2-hydroxy-1-naphthaldehyde. The as-prepared compound showed effective colorimetric single selectivity and high sensitivity for aluminum cation in CH3CN/H2O (1:3) binary solutions. The detection limit is 1.0×10(-8) M Al(3+) based on UV-vis changes.

Preparation, characterization and adsorption properties of a novel 3-aminopropyltriethoxysilane functionalized sodium alginate porous membrane adsorbent for Cr(III) ions.

In this study, we prepared 3-aminopropyl-triethoxysilane (APTEOS) functionalized sodium alginate (SA) porous membrane adsorbent (APTEOS/SA) and tested its adsorption performance for removing of Cr(III) ions. The physico-chemical properties of the pristine and Cr(III) ions loaded APTEOS/SA were investigated by FT-IR, SEM-EDX, TG, AFM, and contact angle goniometer methods. To investigate the adsorption kinetics of Cr(III) ions onto this newly developed APTEOS/SA, we performed a batch of experiments under different adsorption conditions: solution pH, adsorbent dose, initial Cr(III) ion concentration, adsorption temperature, and contact time. The APTEOS/SA exhibited an encouraging uptake capacity of 90.0mg/g under suitable adsorption conditions. To study the mechanism of adsorption process, we examined the Lagergren pseudo-first-order and pseudo-second-order kinetic model, the intra-particular diffusion model, and the Crank model. Kinetics experiments indicated that the pseudo-first-order model displayed the best correlation with adsorption kinetics data. The Crank model showed that the intra-particle solute diffusion was the main rate-controlling step. Furthermore, our adsorption equilibrium data could be better described by the Freundlich equation. We also carried out consecutive adsorption-desorption experiments eight times to show that the APTEOS/SA has encouraging adsorption-desorption efficiencies. The results indicates that the prepared adsorbent is promising for using as an effective and economical adsorbent for Cr(III) ions removal.

Na(6)(H(2)O)(20)(V(10)O(28)) x 4H(2)O, a novel polyvanadate(V) with a three-dimensional framework.

The novel title polyvanadate(V), poly[[octa-mu-aqua-dodecaaqua-mu(4)-octacosaoxidodecavanadato-hexasodium] tetrahydrate], [Na(6)(H(2)O)(20)(V(10)O(28)).4H(2)O](n), contains [V(10)O(28)](6-) anions which lie about inversion centres and have approximate 2/m symmetry and which are linked to [Na(3)(H(2)O)(10)](3+) cations through two terminal and two mu(2)-bridging O atoms. The structure contains three inequivalent Na(+) cations, two of which form [Na(2)(H(2)O)(8)](n) chains, which are linked via NaO(6) octahedra involving the third Na(+) ion, thus forming a three-dimensional framework.

Two-dimensional hydrogen-bond network in bis[(ferrocenylmethyl)dimethylammonium] sulfate pentahydrate.

In the title compound, [Fe(C5H5)(C8H13N)]2(SO4).5H2O, the Fe-C bond lengths lie in the range 2.021 (3)-2.047 (2) A. Intermolecular N-H...O and O-H...O hydrogen bonds link the cations, sulfate anions and water molecules into a two-dimensional hydrogen-bonded network, which stabilizes the crystal packing.