AC600二次侧非能动应急堆芯余热排出系统实验装置及研究计划

ＡＣ６００二次侧非能动应急堆芯余热排出系统实验装置是一座大型非能动安全系统实验研究装置，在设计上，它以热工水力模拟理论及模拟准则为依据，在保持原型系统主要热工水力现象和过程的前提下，对系统进行了必要的简化，本文介绍了该实验装置回路，电气，仪表及测控系统的设计原则和设计结果，以及第一阶段研究计划和内容，最后，根据调试和运行结果总结了设计特点和经验。     

Integrated carbon composite bipolar plate for polymer–electrolyte membrane fuel cells

The electrical resistance of bipolar plates for polymer–electrolyte membrane fuel cells (PEMFCs) should be very low to conduct the electricity generated with minimum electrical loss. The resistance of a bipolar plate consists of the bulk material resistance and the interfacial contact resistance when two such plates are contacted to provide channels for fuel and air (oxygen) supplies.     

Quantitative analysis of micro structural and conductivity evolution of Ni-YSZ anodes during thermal cycling based on nano-computed tomography

Understanding the mechanism of degradation in solid oxide fuel cells (SOFCs) using nickel/yttria-stabilized zirconia (Ni-YSZ) as the anode material is very important for the optimization of cell performance. In this work, the effects of thermal cycling on the microstructure of the Ni-YSZ anode are explored using the three-dimensional X-ray nano computed tomography (nano-CT) imaging technique. It is found that the average Ni particle size increased with thermal cycling, which is associated with the decreased connectivity of the Ni phase and the three-phase-boundary (TPB) length. Moreover, the conductivities of the anode samples are also reduced with the increase in thermal cycle times. The implication of these observations is discussed in terms of the relationship between the conductivity and connectivity of the Ni phase.     

废旧塑料的热裂解技术

介绍了当前国内外几种处理和利用废旧塑料的方法,特别对废旧塑料热裂解制造燃烧油和化学品的技术、工艺流程和存在的问题作了重点探讨。     

FTIR study of thermal cyclization processes in the synthesis of polyetherimidazopyrrolones

An FTIR method was used to investigate the thermal cyclization process in synthesis of polyetherimidazopyrrolones from dietherdianhydrides and 3,3′-diaminobenzidine. It was concluded that the highest degree of cyclization to imidazopyrrolone structure is observed in the case of polymer with bisphenol A group having electron-donating character after dynamic heating, though for the all polyether-imides investigated even at 320°C cyclization are not complete.     

氮化硅反应烧结工艺温度曲线优化的研究

本文针对上海氮化硅制品厂氮化硅反应烧结工艺存在的温度控制重要课题,探讨氮化硅反应烧结工艺温度曲线的优化方法。     

Poly [2-(cinnamoyloxy)ethyl methacrylate-co-octamethacryl-POSS] nanocomposites: Synthesis and properties

Poly [2-(cinnamoyloxy)ethyl methacrylate-co-octamethacryl-POSS] nanocomposites were synthesized from octamethacryl-POSS and 2-(cinnamoyloxy)ethyl methacrylate (CEM) by free radical polymerization. The chemical structures and morphologies of these nanocomposites were determined by FTIR, ²⁹Si NMR, energy-dispersive spectroscopy (EDS), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) techniques. The XRD data showed that the materials were amorphous in nature, indicating that POSS formed an aggregate instead of a crystalline form in the polymer matrix. The POSS-CEM nanocomposites exhibited high thermal stability. Excitation and emission of the CEM-incorporated POSS nanocomposites, studied in the solid state, exhibited blue emission with CIE (x, 0.178; y, 0.137) coordinates, in addition to an emission intensity that increased with increasing CEM (monomer) concentration.     

Compatibilization Effects of PE-g-MA on Mechanical,Thermal and Swelling Properties of High Density Polyethylene/Natural Rubber/Thermoplastic Tapioca Starch Blends

Effect of polyethylene grafted maleic anhydride (PE-g-MA) on mechanical, thermal and swelling characteristic of high density polyethylene (HDPE)/natural rubber (NR)/thermoplastic tapioca starch (TPS) blends were studied. The measurements from differential scanning calorimetric (DSC), dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA), proved the effectiveness of PE-g-MA as compatibilizer in improving the miscibility between HDPE/NR – TPS blends. A decrement in crystallinity index was found after adding PE-g-MA. It is due to restriction in mobility of the HDPE chains. In the presence of PE-g-MA, the blends have better thermal stability. On top of that, the storage modulus which is reflected to the blend stiffness also increased as indicated the improvement in HDPE/NR – TPS interaction.     

Integrated Properties Improvement of Glass/Epoxy FR-4 Copper Clad Laminates via the Modification by Bismaleimide

Abstract

A new matrix system, coded as brominated epoxy (BE), with greatly improved thermal, electric, and dielectric properties as well as water-resistance for copper-clad laminates (CCLs) was developed via the modification of a commercial FR-4 CCLs-based brominated epoxy/dicyandiamide (BEP/Dicy) system with bismaleimide/diallylbisphenol A (BMI/DB). The prepregging parameters were optimized on the basis of the investigations of the reactivity and gel profile of the BE system and the performance requirements of final CCLs. Comparison of CCLs based on the BE system with commercial FR-4 based on BEP/Dicy demonstrated that the former has better integrated properties than does the latter, especially the thermal, electric, dielectric, and water-resistance properties. For example, the values of the dielectric constant and dielectric loss of optimized BE-based CCLs are only 74%, and 50%, respectively, that of commercial FR-4, meanwhile, the glass transition temperature of the former is 68°C higher than is that of the latter. Moreover, the water resistance of the former is 68% lower than is that of the latter, suggesting that BE could be a potential candidate for a high performance matrix for CCLs with wide applications.     

Organosoluble semi-alicyclic polyimides derived from 3,4-dicarboxy-1,2,3,4-tetrahydro-6-tert-butyl-1-naphthalene succinic dianhydride and aromatic diamines: Synthesis,characterization and thermal degradation investigation

Semi-alicyclic polyimides (PI-1–PI-4) have been prepared from a newly-developed alicyclic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-6-tert-butyl-1-naphthalene succinic dianhydride (TTDA) and various aromatic diamines. The asymmetrical alicyclic tetralin structure in TTDA endowed the derived PI resins good solubility in various organic solvents. They were soluble not only in polar aprotic solvents but also in solvents with low boiling points including dichloromethane and tetrahydrofuran. Flexible and tough PI films were successfully cast from their N-methyl-2-pyrrolidone (NMP) solution except PI-1 derived from TTDA and 4,4′-oxydianiline (ODA). The PI films exhibited good optical transparency in the ultraviolet and visible light region with optical transmittances around 80% at a wavelength of 400 nm. The PI films showed good thermal stability up to 400 °C in nitrogen, after that they thermally decomposed rapidly. The thermal degradation behaviors of the PIs were investigated by means of thermogravimetric analysis-mass spectrometry (TG-MS), thermogravimetric analysis-Fourier transform infrared spectrometry (TG-FTIR) and the real time FTIR spectra (RT-FTIR) analysis techniques. The results revealed that the decomposition of PI-1 (as a representative) took place mainly in the range of 450–550 °C. The major degradative fragments at 500 °C were clearly identified as the tert-butyl-substituted tetralin moiety and its dealkylation products. Therefore, it can be deduced that for the TTDA-PIs, the single bond bridge attached the maleic anhydride and tetralin anhydride units in TTDA moiety might break first during the heating; thus producing the tetralin fragments.