Advanced Materials Research Vol. 1088

Abstract: Under hydrothermal conditions, two copper phosphonates, [Cu₂(H₂O)₂(H₂L)(bpy)₂(H₃L)₂]·2H₂O (1) and [Cu₂(H₂O)₂(H₂L)₂(phen)₂]·6H₂O (2) (H4L = p-xylylenediphosphonic acid, bpy = 2,2'-bipyridine and phen = 1,10-phenanthroline), have been synthesized using diethyl p-xylylenediphosphonate (dixdp), in which p-xylylenediphosphonic acid (H4L) was generated via in situ hydrolysis. Complexe 1 forms a zero-dimensional (0D) bimetallic rings, while complex 2 features a 0D structure containing two kinds of partially deprotonated H₃L^- and H₂L^2- ligand.

Abstract: Employed isophthalic acid and Quinoxaline as co-ligands, a new 3D metal-organic framework [{Cu₂(IPT)₂(QA)₂}₆]n ((H₂IPT= isophthalic acid, QA = Quinoxaline) had been prepared under hydrothermal condition. The compound crystallizes in the Rhombohedral space group R-3c, with cell parameters, a = 30.099(4) Å, b = 30.099(4) Å, c = 18.190(4) Å, a= β = γ = 90˚, V = 14271(4) nm³ and Z = 12. This 3D complex based on rhomboid-shaped structural unit [{Cu2(IPT)2(QA)2}6] shows unusual USF-1 topology. On the basis of the results of TG/DTA analyses, the structure is thermally stable up to 300 °C.

Abstract: Pyrolysis behavior of a new kind of polybenzoxazine with aldehyde groups was investigated by pyrolysis gas chromatography-mass spectroscopy (PyGC-MS) at the temperatures ranging from 450°C to 750°C. It was found from the pyrolysis chromatograms that the type and amount of its pyrolysates obviously change with pyrolysis temperature due to various pyrolysis behaviors at different temperatures. From the structures and relative contents of the pyrolysates, the pyrolysis mechanism of the polybenzoxazine was described as follows: the initial degradation reactions occurred mainly at the C_methylene-N bond, followed by the C_phenyl-C _methylene bonds.

Abstract: Substituent group effete; Cyanide anion; Anion recognition; Theoretical computationAbstract. In this paper, the cyanide anion recognition of the [Ru2(bpy)4(mbpibH2)]4+ (mbpibH2 is 1, 3-bis([1, 10]-phenanthroline-[5, 6-d]imidazol-2-yl)- benzene) functional molecular material host based on hydrogen bond weak interactions was discussed by using the quantum chemistry theory and method, the density function Becke, three-parameter, Lee-Yang-Parr, DFT/B3LYP/6-31G*//SDD computational level, especially discussed the geometry structure of the recognition system. The results showed that the substituent group of Ru(bpy)2(mbpibH2) structure moieties have very important role in the recognition of the CN- anion. This study may be helpful for the further design and investigation the [Ru2(bpy)4(mbpibH2)]4+ (mbpibH2 is 1, 3-bis([1, 10]-phenanthroline-[5, 6-d]imidazol-2-yl)- benzene) involving functional molecular derivation receptors with excellent and selective anion recognition functions.

Abstract: AlF₃ and MgF₂ were applied to modify the surface of the LiNi_1/3Co_1/3Mn_1/3O₂ cathode material. The structural and electrochemical properties of the materials were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), charge–discharge tests and electrochemical impedance spectra (EIS). The results show that the 1 wt.% AlF₃ and 1 wt.% MgF₂ coated LiNi_1/3Co_1/3Mn_1/3O₂ (NCM333) cathode material exhibits an optimized electrochemical performance. It presents an initial capacity of 207.2mAh/g and 169.1mAh/g at 0.2C between 2.8V and 4.7V after charge-discharge 65 cycles. The rate performance is also enhanced because the coating decreases the interface charge transfer impedance.

Abstract: Mercury is a striking pollutant and mercury emissions from coal-fired power plants are under environmental regulation. The primary objective of mercury abatement in coal-fired power plants is to remove elemental mercury. Sorbent injection is one of the major commercially available technologies for mercury control from coal fired power plants and activated carbon is the most commonly employed sorbent. Modified activated carbons have been found to exhibit high mercury emission reduction efficiency. Noble metal and metal oxides also showed excellent mercury adsorption capacity. Fly ash, a waste product from coal-fired solid wastes, may be an excellent adsorbent owing to its low cost and abundance. There is no consistent evidence for the adsorption mechanism of mercury on modified activated carbon; a popular view is that the sorption mechanism is combination of physisorption and chemisorption.

Abstract: A novel cathode material, lithium and natrium decavanadate (Li₂Na₄V₁₀O₂₈) with three-dimensional tunnels framework structure for lithium ion battery, has been prepared by hydrothermal synthesis and followed annealing treatment. The molecule structure and electrochemical properties of the samples have been further characterized. The novel material shows good reversibility for Li+ insertion/extraction and long cycle life. High discharge capacity (262 mAh/g) is obtained at 0.2mA/cm2 discharge current and potential range between 1.5~4.5V vs. Li⁺/Li. AC impedance for the Li/Li₂Na₄V₁₀O₂₈ cell reveals that the cathode process is controlled mainly by Li⁺ diffusionin the active material.

Abstract: In this study, the thermal oxidative degradation behavior of thermotropic liquid crystal copolyesters P-BPAFx containing 2.5-10 mol% bisphenol AF unit were evaluated by thermogravimetric analysis (TGA) technique under air atmosphere and the degradation activation energy (E) was obtained from Kissinger and Kissinger-Akahira-Sunose (KAS) method. The degradation behavior of copolyester are strongly dependent on the molar percentage of BPAF unit. Results showed that the E values obtained by the two methods increase first and then decrease slightly with increasing the BPAF unit and follow the order P-BPAF5.0< P-BPAF10<P-BPAF2.5, indicating P-BPAF2.5 has good thermal stability. The reason for this phenomenon was discussed in detail in the text.

Abstract: With Raney nickel catalyst and aniline solvent, the reaction kinetics of catalytic hydrogenation of isophthalonitrile (IPN) for meta-xylenediamine (MXDA) preparation is studied in this paper. The experiment is conducted in a 1L büchiglas high-pressure hydrogenation reactor under the condition of the reaction temperature (100°C) and the reaction pressure (35 bar). The results shows that the kinetics equation proposed in this paper can be used to predict the response speed of IPN accurately.

Abstract: In the paper, the optimization of the coagulation process for Kaolin and humic acid removal using polymeric aluminum ferric sulfate (PAFS) was studied. In order to obtain the maximum turbidity and humic acid removal efficiency of Kaolin and humic acid simulated wastewater, the optimum coagulation conditions was investigated with the factors of mixing speed and time. Furthermore, mixing speed and time including parameters affecting the coagulation performance such as rapid mixing speed, rapid mixing time, slow mixing speed and slow mixing time using single factor and orthogonal array L9 (34) analysis were examined. The results showed that the optimum single factor of mixing speed and time indicated rapid mixing speed of 350 rpm, rapid mixing time of 1.0 min, slow mixing speed of 60 rpm and slow mixing time of 20 min. Then the orthogonal optimization experiment of mixing speed and time indicated maximum HA removal efficiency was 97.5% at rapid mixing speed of 350 rpm, rapid mixing time of 1.25 min, slow mixing speed of 60 rpm, and slow mixing time of 20 min.