熔加色素法搪瓷色釉结构的研究

用ＳＥＭ、ＷＤＳ、ＩＲＲＳ、ＸＰＳ和ＡＳＳ对搪瓷色釉结构进行了研究熔加法的搪瓷色釉具有均匀分布的小尺寸、数量小的气孔。分析了搪瓷色釉的Ｏ１ｓ谱，并分解了成桥氧、非桥氧、及自由氧。熔加法的桥氧浓度远大于磨加法，而熔加法的非桥氧的浓度远低于磨加法，这表明熔加法的搪瓷色釉的结构强度高于磨加法。     

钝感炸药在机械撞击下爆炸危险性评价

介绍了用炸药撞击声压级－实验药量曲线评价钝感炸药在机械撞击作用下发生爆炸的危险性的方法和测试结果，并与苏珊试验、滑道试验等测试结果进行了比较和讨论。     

A comprehensive assessment of supported titania photocatalysts in a fluidized bed photoreactor: Photocatalytic activity and adherence stability

Titania (TiO₂) was immobilized onto hydroxylated glass beads (HGB) via the thermal bonding and sol–gel coating methods. The photocatalytic activity and adherence stability of the prepared supported photocatalysts were studied in a fluidized bed photoreactor. P25 thermally bonded HGB was found to be more active than sol–gel coated HGB prepared with the same immobilization conditions, while both of them exhibited poor adherence stability, i.e., large amounts of immobilized TiO₂ detached from HGB during the degradation. The adherence stability was improved with limited extents by increasing the calcination temperature or reducing the coverage of TiO₂ on HGB, but either of these approaches resulted in lower activity. The poor adherence stability was ascribed to the fluid shear force and particle friction in fluidized bed, as well as the insufficient bonding between TiO₂ and HGB in terms of the bonding mechanism.

Hydroxylated quartz sands (HQS) and silica gel beads (SGB) were further studied and used as supports. Results have shown that the adherence stability was significantly improved with SGB but only slightly improved with HQS. Characterizations results showed that a coarser surface and more surface Si–OH groups could improve the adherence stability of supported TiO₂ photocatalysts.     

有机硅改性丙烯酸酯的研究进展

综述了有机硅改性丙烯酸乳液的合成、乳化体系、聚合方法及改性研究进展。     

二聚酸改性尼龙-66共聚物的结构和性能

考察了二聚酸对尼龙-66性能的影响,对共聚物进行了表征.结果表明加入二聚酸可降低尼龙-66的密度、熔点及吸水率,显著提高柔性和缺口冲击强度;但二聚酸加入量大时,增韧能力减弱.二聚酸的存在可促进共聚物的α、β晶相减少和细化,还可抑制酰胺基团的活性,有利提高尼龙-66的热降解温度和改善热稳定性.     

Free‐radical grafting of acrylic acid onto isotactic polypropylene using styrene as a comonomer in supercritical carbon dioxide

Free‐radical grafting of acrylic acid (AAc) onto isotactic polypropylene (iPP) using styrene (St) as a comonomer in supercritical carbon dioxide (SCCO₂) medium was studied. The effects of temperature and pressure of reaction on functionalization degree (grafting degree of AAc) of the products were analyzed. The increase of reaction temperature increases the diffusion of monomers and radicals in the disperse reaction system of SCCO₂. In addition, the increase of temperature accelerates the decomposition rate of 2,2′‐azobisisobutyronitrile (AIBN), thus promoting grafting reaction. It was also observed that functionalization degree of the products decreases with the increase of pressure of SCCO₂ in the range of experiment. The effects of comonomer St on the functionalization degree of the products were investigated. The AAc graft degree of the resulting polymer was drastically higher in the present of St. It reached a maximum when the mass ratio of St and AAc was about 0.7 : 1. Because AAc is not sufficiently reactive toward iPP macroradicals, it would be helpful to use a second monomer that can react with them much faster than AAc. St preferentially reacts with the iPP macroradicals to form more stable styrene macroradicals, which then copolymerize with AAc to form branches. The highest functionalization degree was obtained when the AIBN was 0.75 wt %. When the initiator was used excessively, the functionalization degree decreased because of severe chain degradation of the iPP backbone. The morphologies of pure iPP and grafted iPP are different under the polarizing optical microscope. The diameter of the pure iPP spherulites is 20–38 μ and that of the grafted iPP spherulites is reduced with the increase of the functionalization degree of the products. This is proposed to be because the polar grafts formed during the reaction would have a tendency to associate in the hydrophobic PP environment. This might preserve some of the local crystalline order that existed during the reaction in the swollen iPP phase. It can be proven by a DSC cooling investigation that the crystallization temperature increased as the functionalization degree increased. This is proposed to be because the side‐chain of grafting polymer helps to bring about the heterogeneous nucleation in grafting polymer. Therefore, a large number of nuclei can emerge to a lesser supercooling degree. It can be also proven that the percent crystallization decreased as the functionalization degree increased, probably due to the grafted branches, which disrupted the regularity of the chain structure and increased the spacing between the chains. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2203–2210, 2004     

DETERMINATION OF EQUILIBRIUM VAPOR COMPOSITION FROM THE VAPOR PRESSURE OR BOILING POINT OF THE SOLUTION BY DIRECT METHOD

A direct method for evaluating equilibrium vapor compositions from measurements of the vapor pres-sure or boiling point of the solutions is presented.The basic differential equations are derived from Gibbs-Duhem equation and can be solved easily by iterative method.This method can be successfully used forbinary systems,and in principle can also be applied to multicomponent systems.Several examples ofbinaries and ternaries are presented for demonstration.Calculated results are in good agreement with ex-perimental data.     

感光材料内包装黑色膜的制造工艺与性能

感光材料包装膜分为内包装膜和外包装膜。本文主要介绍内包装用黑色膜的技术现状,制造工艺,包括原材料的选择,工艺技术路线及关键设备,并列举了产品主要规格与性能指标以及加工应用。     

稀土氧化物掺杂ZnO-Bi2O3系压敏陶瓷"软心"现象的研究

掺杂稀土氧化物的大尺寸ZnO压敏陶瓷具有明显的“软心”特征,即内部电位梯度远远低于表层。经过XPS关于Zn结合能的研究、SEM关于杂质分布状况的研究及XRD关于相态的研究表明:试样内部氧和添加剂的匮乏及晶态的不完善是影响内层电位梯度的三大主要因素。     

低温养护条件下粉煤灰混凝土早期强度研究

低温（0～10℃）养护条件下，粉煤灰细度、掺量，早强剂和矿渣对粉煤灰混凝土早期力学性能的影响。超细粉煤灰较Ⅱ级粉煤灰更能提高混凝土低温下的早期强度，早强剂和矿渣的加入也有助于混凝土早期强度的提高，而采用矿渣磨细粉与超细粉煤灰双掺的办法不仅可以比较有效地提高混凝土的早期强度，还能改善混凝土的和易性。