Advanced Materials Research Vols. 455-456

Abstract: The liquid-liquid equilibrium (LLE) of ternary mixtures (water + palm oil biodiesel + methanol) was measured under atmospheric pressure and temperatures of 303.15K, 313.15K and 323.15K. The mutual solubility of biodiesel and water increased as the increasing of ratio of methanol. Also, the mutual dissolution of the mixture was slightly promoted by increasing temperature. The phase diagrams and tie lines for the ternary system were determined by high-temperature gas chromatography (HTGC). NRTL and UINQUAC models were applied to fit the experimental data for the ternary system, and the binary interaction parameters were obtained by regression on the experimental data. Both models could describe the LLE behavior of the systems fairly well.

Abstract: The oxidation of N-phosphonomethyliminodiacetic acid (PMIDA) to prepare glyphosate (PMG) over active carbon was investigated. Experiments were carried out with O₂ as the oxidizing agent in a 150-mL autoclave made in stainless steel, with reaction temperature ranging from 323.15 to 353.25K and the pressure from 0.12 to 0.40 MPa. The macro kinetic model of the reactions in series was developed, and the pre-exponential factor and activation energy were estimated from the measured data in experiments. The influence of dissolved oxygen concentration was also considered in this macro kinetic model. The results indicated that the two step reactions are all one-order to reactant (PMIDA or PMG) and 0.3 or 0.07 to O₂ respectively. The active energy was 12.98kJ/mol for the first step reaction and 10.87kJ/mol for the second step reaction.

Abstract: Using the second o-nitro aniline and benzoyl chloride as the initial raw materials, a green light-emitting materials (pbi)2Ir (acac)2 was produced utilizing a new designed synthesis plan. The complex’s structures were characterized by IR, MS, and the differential thermal analysis. The optical Luminescence Properties of the complex was studied by the fluorescence spectrometry analysis. The melt point of the product is 343°C which showed that it had thermal stability.. The fluorescence spectrometry analysis experimental results show that the Excitation and emission peaks of the organic Iridium (Ⅲ) complexes got were respectively 470.6nm and 526.21nm which showed that it belong to green high-brightness light-emitting materials. The oxidation of the intermediate products exposed in air which could cause the quality of product instability was avoided in the new synthesis plan improved.

Abstract: The Li3V2(PO4)3/C cathode material is prepared by fast microwave synthesis route using PEG as carbon source. The samples were characterized by X-ray diffraction (XRD), galvanostatically charge/discharge test and electrochemical impedance spectroscopy (EIS). XRD result shows that the material was well crystallized and the structure was indexed as a monoclinic Li3V2(PO4)3/C. The electrochemical tests of material exhibit good cycling performance, which delivered a high initial discharge of 125.2 mAh g-1 at 0.2C and the retention of capacity was 92.4% after 50 cycles. From this study, the PEG-based microwave preparation method is regarded as a feasible route for the preparation of Li3V2(PO4)3/C cathode material.

Abstract: As anode material of battery, manganese dioxide has been widely used in zinc-manganese and lithium–manganese primary battery. To meet new electrical products’ requirements on high-performance battery, research on rechargeable lithium manganese button batteries with extensive operating temperature, superior-performance comprehensive electrochemistry and low cost has drawn attention from more and more researchers. This article has analyzed physical and chemical properties of lithium manganese composite oxides synthetic material, assembled lithium button batteries by synthetic sample and lithium aluminum alloy and discussed its electrochemistry performance, based on confirmed material proportioning, discussed the influence of roasting condition on synthetic material performance from physical & chemical properties and electrochemistry properties, and confirmed best roasting temperature and roasting time.

Abstract: The synthesis of a new triazene reagent 1-(4-antipyrine)-3-( 3-nitroaniline)-triazene (ANTA) and its color reaction with Hg (Ⅱ) was studied and a new spectrophotometric method for the determination of Hg (Ⅱ) was established. The results showed that in the presence of micromulsion Tween-80, ASTA could reacted with Hg ( Ⅱ) to form a red stable complex of which the molar ratio of reagent︰metal was 2︰1 in Na₂B₄O₇-NaOH medium.. The maximum absorption peak of the complex was located at 495 nm with the apparent molar absorption of 3.8 ×10⁵ L·mol^-1·cm^-1. Beer′s law was obeyed in the range of 0.32～10 μg/10 mL for Hg ( Ⅱ) and the detection limit was 0.10 mg/L. Many ions did not interfere the colour reaction system due to the existence of ammonia. This method was applied to determination of Hg (Ⅱ) in lead-zinc ore samples, and the results were in accordance with those obtained by AAS method. Recovery was in the range of 103.0～103.2 % and the RSD(n=6) was not more than 4.6%.

Abstract: A novel pH-sensitive poly (2-(acryloyloxy) propanoic acid) hydrogel (PAPA) synthesized from lactic acid by radical polymerization has been investigated in this work. The structure of prepared monomer 2-(acryloyloxy) propanoic acid) (APA) has been characterized by FTIR and ¹H-NMR measurements. PAPA hydrogel demonstrated an obvious pH sensitivity in its swelling in the range of 4-7 pH of phosphate buffer solution (PBS). The rapid response of the hydrogel makes it suitable for drug delivery application. Here, salicylic acid (SA) selected as a model drug, the in-vitro drug release as a function of pH and temperature was studied systematically. The cumulative release of salicylic acid reached up to 86.6% in pH=7.4 PBS at 37.0°C within 550min. In pH=2.1 PBS, however, only 26.6% drug was released from the pH-sensitive PAPA on the same conditions.

Abstract: The active technology of the mechnochemistry process is studied. Structure of chitin during this process is characterized by infrared spectroscopy (IR) and scanning electron microscopy (SEM). Different mechanical activating time and size of shrimp shell have effects on solubility, which have been examined respectively. The results indicate that the mechanical-chemical process cause remarkable impact on changing molecular structure, among which stirring time、quantity of shrimp shell ground at a time are the most obvious phenomenon effecting water-solubility of chitosan. The crystal structure of chitin in shrimp shell is destroyed in mechanical-chemical process and changed from chitin to chitosan in a short time, taken off the acetyl group.

Abstract: The solubility of lithium bromide in mixed solvents formed by acetone and water was determined in the temperature range between (293.15 and 323.15) K using a static analytical method. The solubilities of LiBr in mixed water-acetone solutions are predicted with the LIFAC model and its original interaction parameters. The average absolute deviations of the calculated values from the experimental data and mean relative deviations for this system were 0.0742 and 0.7349, respectively .The results show that the LIFAC model can be used to predict solid-liquid equilibrium of Acetone + water + Lithium Bromide.

Abstract: The determination of polycyclic aromatic hydrocarbons (PAHs) in coal tar was systematically studied by the high performance liquid chromatography (HPLC), in which involved separation, qualitative and quantitative determination of PAHs. The series of key techniques and experiences were summarized. To ensure finely separation of PAHs PAH, using C18 bonding silica gel column, mobile phase of methanol-water, and theoretical plate number of column more than 5600 were needed. For quantitative determination, the external standard (E-X) quantitative method and external standard - response factor (E-F) quantitative method were recommended. For accurately quantitative determine PAHs, the key technologies were recommended including choice of the optimum solvent of samples preparation and optimum concentration and using ultrasonic treatment, etc. In addition, some determination typical coal tars were also given and recommended. .