Advanced Materials Research Vols. 1030-1032

Abstract: The detection of formaldehyde is very necessary and important in both industrial and residential environments. In this paper, a novel quartz crystal microbalances (QCM) formaldehyde gas sensor has been successful fabricated based on Polyethylenimine (PEI)-multi-walled carbon nanotubes (MWCNTs) composite films by the spraying process. The morphology of films was analyzed by scanning electron microscope (SEM), and formaldehyde-sensing properties of sensors were investigated. The results showed that the prepared QCM gas sensor exhibited good response and recovery behaviors towards formaldehyde gas in the concentration range of 0-10 ppm at room temperature, which also has the superior repeatability and selectivity. Moreover, the gas-sensing mechanism of sensors was studied.

Abstract: In order to analysis the force situation of the material which is discontinuity,we can used the new theory called peridynamics to slove it.Peridynamics theory is a new method of molecular dynamics that develops very quickly.Peridynamics theory used the volume integral equation to constructed the model,used the volume integral equation to calculated the PD force in the horizon.So It doesn’t need to assumed the material’s continuity which must assumed that use partial differential equation to formulates the equation of motion. Destruction and the expend of crack which have been included in the peridynamics’ equation of motion.Do not need other additional conditions.In this paper,we introduce the peridynamics theory modeling method and introduce the relations between peridynamics and classic theory of mechanics.We also introduce the numerical integration method of peridynamics.Finally implementation the numerical integration in prototype microelastic brittle material.Through these work to show the advantage of peridynamics to analysis the force situation of the material.

Abstract: Under the aerobic condition, using tap water as solvent, the super absorbent resin was synthesized by solution polymerization of acrylic acid-sodium acrylate, The result showed the water absorbency of last production in tap water was 578g/g, when the concentration of monomer was 25%, the neutralization degree of monomer was 80%, the amount of initiator and crosslinking agent was 0.15% and 0.07% respective, the react temperature was 90°C and the time of reaction was four hours. the crosslinking action of crosslinking agent was not influenced, although tap water was used as solvent. Which will has important directive significance to the large-scale industrial production of high polymer absorbent resin.

Abstract: Carbon-14 is a radionuclide, which is a by-product in the operation of various nuclear reactor facilities. it also came from the interaction of cosmic ray with nitrogen and hydrogen in the atmosphere globally. This article elaborates the source of the ¹⁴C in High-Temperature Gas-Cooled Reactor, the amount of ¹⁴C released to the environment, as well as the forms of carbon-14. Meanwhile, the author presents the environment impact of this radionuclide. This paper concluded that ¹⁴N (n, p) ¹⁴C reaction in the fuel spheres and coolant gas is major source, and CO₂ is major release form. The conclusion could provide the references and suggestions for storage, disposal and release reduction of this type of waste.

Abstract: This paper studies the effect on absorbing property of content and length of the carbon fibers of λ/4 type absorber made of carbon fiber membrane and gypsum board. The experimental results show that absorbing property of λ/4 type absorber made of carbon fiber membrane and gypsum board firstly increases and then decreases with the increase of the content or length of the carbon fibers. The absorbing property is best while carbon fiber membrane’s length is 2mm and content is 2.8% composited with gypsum board whose thickness is 1.5cm. The maximum absorption is-27.08dB.

Abstract: In this paper, the effect of C₃H₆N₆modified by imidazolium based Ionic Liquid 1-butyl-methylimidazolium hexafluorophosphate ([BMIM]PF₆) on polyurethane rigid foam flame retardant properties was conducted.The results show that the flame retardant properties of C₃H₆N₆ modified with Ionic Liquid significantly increased and the LOI increased form 22.3 to 24.5. In the modification process, the ionic liquid mass have a very noticeable effect to the flame retardant property and when [BMIM]PF₆ and C₃H₆N₆ in quality was 4:6, Fire-retardant effect was best.Compared with the prior to the modification, C₃H₆N₆ modified can increase effective Flame resistance of materials, horizontal burning speed from 67.6mm/min down to 33.4mm/min.Thermal degradation data show that C₃H₆N₆ modified could improve initial decomposition temperature and reminder yield of rigid polyurethane foam,and then heat release reduced, the decomposition controlled,thermal stability increased.

Abstract: Due to the rapid growth of traffic, serious overload problems and so on, there are severe early damages on some of the highways, and affected by cold weather and water, the highways are lack of timely, quick fixes. Epoxy emulsified asphalt can be constructed in cold damp conditions, it can improve traffic conditions and extend the life of the old road and so on^[1]. Given that there aren’t any relatively mature design methods at home and abroad yet, the paper is based on modified Marshall test method and studies the Epoxy emulsified asphalt mixture design method and proposes again modified Marshall test design methods.

Abstract: A method of synthesizing the FLG/CNF nanopaper on hydrophilic polycarbonate membrane was investigated. The synergistic effect of few-layer graphene (FLG) and carbon nanofiber (CNF) on the electrical conductivity of shape-memory polymer (SMP) composites reinforced by the FLG/CNF nanopaper was explored. The conductive FLG/CNF nanopaper facilitates the actuation in SMP composite induced by electrically resistive heating. The heat conduction in a nanopaper depends greatly on FLG/CNF network formation. The morphology and structure of the FLG/CNF nanopaper are characterized with scanning electronic microscopy (SEM). The flat surface and tunable network structures observed from the microscopic images indicate that the FLG/CNF nanopaper could have highly conductive property. Detailed structural characterization indicates that the three-dimensional networks of nanopaper, result in both the reduction of thermal contact resistance and the enhancement of conductive property along the thickness.

Abstract: The temperature dependence of physical properties of iron and their temperature peculiarities curves have been investigated. The influence of the time-temperature treatment (TTT) on the efficacy of the modification of iron including durable have been also determined.

Abstract: To improve the harrow disk made of 65Mn steel working life, an ion implanting metal in order to obtain tungsten carbide treatment was proposed in this work. Microstructure and phase composition of 65Mn steel obtained by ion implanting tungsten carbide process were analyzed by optical microscope and XRD, respectively. The surface hardness was tested by microscopic hardness tester, and the wear resistant performance of the wear layer was tested by abrader abrasor. The results showed that the micro-hardness of ion implanting tungsten carbide layer can be reached 1100 HV0.2, higher than that of 65Mn steel, the thickness of tungsten carbide layer was 400μm, which greatly improve the wear resistance. Harrow disk after the ion implanting tungsten carbide exhibited the excellent wear resistance in the sandy soil, and its working life was more than twice the length of the genera treatment harrow disk.