Papers by Keyword: Anion

Abstract: Samplings of PM_2.5 used to determine water-soluble anions were obtained from four representative sites of Hefei. There are High-tech zone, Binhu new area, Hupo villa, Dongpu reservoir. The other samplings of PM_2.5 used to determine metal elements came from four kinds of domestic waste combustion. There are paper, plastic, cotton, rubber. In this article, anions were detected by ion chromatography (IC). It was found that the main anions in PM_2.5 are NO₃^-, SO₄^2-. Metal elements were detected by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Fe, Mn, Zn, Cu, Cd, Cr six kinds of metal elements were detected in this article. The main metal elements in samplings of PM_2.5 are Fe and Cu element. The concentrations of Cd and Cr elements are lower in four domestic waste burning.

Abstract: Through the polymerization and grafting reaction of bisphenol A dianhydride and bisphenol A diamine, the polyimide activator (PI activator) of acyl caprolactam end capping is obtained and then the anionic in-situ polymerization modified nylon 6 resin is obtained. Viscosity analysis shows that PI consumption is higher than 0.1 (of monomer mass), the reaction temperature is higher than 160°C, the viscosity rises rapidly in a short time and the rapid polymerization molding can be realized; when PI consumption is higher than 0.15 (of monomer mass), the water absorption of matrix resin will be lower than 1.4%; compared with the nylon resin, its water absorption is significantly lowered and its mechanical property is improved greatly; microscopic analysis shows that PI molecules fail to enter the crystalline phase of the nylon 6 and form lamellar crystals in the nylon matrix, which plays a role of enhancement and obstruction; differential thermal analysis shows that PI reduces the melting enthalpy and melting point temperature of nylon 6 resin, which indicates that PI reduces the crystallization capacity of nylon 6.

Abstract: Small-molecule fluorescent probe with advantages of small size, low background and simple preparation have been widely used. The detection of anions by small-molecule fluorescent probes is usually achieved through one of the following reaction mechanisms: hydrogen bonds and electrostatic interactions; metal or Lewis acid coordination; covalent interaction. This article summarizes the advances in the design principles of small-molecule fluorescent probes for the detection of anions in biological and environmental media in recent years.

Abstract: Cermet alloys are a combination of ceramic and metal. Therefore, cermets exist in high corrosion resistance in aqueous media. However, because of the nature of cermet alloys, which have a metal and ceramic composition, the corrosion rate is complex to identify. The corrosion attack could be assessed by calculating the corrosion rate or through electrochemistry evaluation. Generally, the corrosiveness of media increased as the anions contents increased. This paper presents the corrosion mechanism of cobalt tungsten-carbide (WC-Co) exposed to a high concentration of sulphate in the salinity of seawater. The solution (media) was prepared according to the same composition as seawater including pH, salinity and dissolved oxygen. The corrosion rate was then identified and the corrosion mechanism revealed. The corrosion rate was identified at 4°C, 20°C, 50°C and 80°C and compared with the corrosion rate of WC-Co in seawater. The results revealed that sulphate has an inhibiting effect that minimises the corrosion attack on WC-Co. The corrosion rate decreased as the sulphate content in seawater increased, and an increase in the temperature increased the corrosion attack on WC-Co.

Abstract: Kinetic parameters are calculated based on the reactive temperature rise curve measured by adiabatic approach at the temperature of 145 to 160 °C with the catalytic system of NaOH and acyl caprolactam End-capped butadiene-acrylonitrile rubber (CHTBN) or styrene-butadiene rubber (CHTBS). The reaction order is first order, the activation energy is between 72.91−73.16 kJ∙mol⁻¹ and the pre-exponential factor is between 3.22×10¹¹− 3.38×10¹¹ mol¹⁻ⁿ∙s⁻¹ in the system of CHTBN/NaOH. While in CHTBS/NaOH, the reaction order is between 1.23-1.34, the activation energy is between 85.55－86.88 kJ∙mol⁻¹ and the pre-exponential factor is between 4.52×10¹¹−5.0 9×10¹¹ mol¹⁻ⁿ∙s⁻¹. The adiabatic reaction kinetic model of caprolactam anion was constructed based on the existing research findings, by which the polymerizing reaction is simulated. The coincidence between the simulation results and the experimental data revealed that the model is reasonable and correct.

Abstract: Kinetic parameters were calculated based on the catalytic reaction systems of sodium caprolactam salt、N-75 biuret and at the temperature of 145 to 160 °C. The reaction order was approximately first order. The activation energy was between 73.2−77.1 kJ∙mol⁻¹ and the pre-exponential factor was between 2.9×10¹¹−3.6×10¹¹ mol¹⁻ⁿ∙s⁻¹. The calculated reaction heat of 134.5−137.3 J∙g⁻¹ was in consonance with the literature value of 138.6 J∙g⁻¹. The adiabatic reaction kinetic model of caprolactam anion was constructed based on the existing research findings. The coincidence between the simulation results and the experimental data revealed that the model was reasonable and correct.

Abstract: We developed a device for automatic closed friction and analyzed its test results in this paper, which showed the influence factors in the test methods of textile negative ion occurrence amounts. The textile negative ion occurrence amounts in different time stages were tested in this process; the analysis of its influence of temperature and humidity has certain reference significance for improving testing device for testing textile negative ion concentration, on the basis, functional textiles were also studied. Finally, we put forward the influence factors in the test methods of textile negative ion occurrence amounts.

Abstract: A nano-material named opal blended with polymer, then were added into slurry, after a series of special paper-making process, the rice paper releasing anion was successfully prepared by us. By test of SEM, we observed nano-structure morphology in the image of opal particle and rice paper sample. A series of mechanical properties had been tested as GB18739 or QB/T3515 standard. After testing of anion concentration, maximum of rice paper reached -9510cm^-3，meet the needs of human health. There is no doubt opal is a kind of environmental material for human health.

Abstract: It is mainly addressed the rare necessary components in the Zijin Stone, and its anion releasing phenomenon, using X-rayfluorescence spectrometer to analysis the composition of elements, and using the DLY-6A232, one large gas ion test to identify the mount of the anion released.Many kinds of trace elements containing in the stone necessary for human, such as KCaAlFeTiVCrSrCuMgMnZn, and the mount of anion released as much as 1409 ion/cm^-3 both are important and vital factors to benefits our health.

Abstract: It is mainly addressed the relation between the structure and the energy domain using scanning electron microscope (SEM), transmission electron microscopy (TEM) to observe the micro structure. It indicates that some specific micro structures exiting in the Zijin Stone, such as the nanocrystal structure, nanofiber structure, and nanolayer structure, by which the capacities of releasing anion, bactericidal effect can to some extent be explained.