无铅焊锡线中无卤素免清洗助焊剂的研制

研制了一种新的用于无铅焊锡线中的无卤素助焊剂,选取芳香族酸、二元羧酸以及有机胺为活性剂主要成分.并参考日本工业标准JIS-Z-3282-2000和相关国家标准GB/T 9491-2002对其进行了全面的性能测试.结果表明,该助焊剂在可焊性、绝缘性、腐蚀性等方面均符合标准.扩展率大于80%;表面绝缘阻抗大于1011Ω;无腐蚀性.且具有焊接效果良好、无卤素、无毒、环保,焊后免清洗等优点.     

聚丙烯膨胀型无卤阻燃体系中协同效应的研究

研究了膨胀型无卤阻燃体系中协同阻燃剂对聚丙烯阻燃效果及流动性的影响,研究结果表明：协同阻燃剂的加入显著提高了ＰＰ 的阻燃性能,彻底克服了熔滴现象,合适的Ｐ－ Ｃ－ Ｎ 比例是形成优质炭层的保证;抑烟效果显著;明显改善了ＰＰ 阻燃体系的熔体流动性。     

环保型阻燃剂的研究与应用

提出了含卤阻燃剂在应用中造成的污染及潜在危险性,阐述了无卤阻燃剂阻燃机理、研究现状及应用情况,并指出环保型阻燃剂是阻燃剂发展的趋势。     

Characteristic Effects in Degradation and Stabilization of Halogen-Containing Polymers

Abstract

Fundamental characteristics of halogen containing polymers are reviewed to identify new approaches for their stabilization.     

Monatomic oxygen adsorption on halogen-substituted monovacant graphene

Doping of graphene-based materials with heteroatoms relies on the disruption of existing charge densities found on pristine graphene. Even though it is known that this phenomenon helps catalyze oxygen reduction reaction (ORR), there are only a few theoretical studies regarding the use of halogen as dopants despite their high electronegativity differences with carbon. Using density functional theory calculations, this work explores the low-concentration halogenation of monovacant graphene as well as the adsorption of oxygen atom onto resulting halogen-based substrates (X = F, Cl, Br, I). In general, formation of doped graphene and the subsequent adsorption of monatomic oxygen is more favored in non-coplanar systems than in their coplanar counterparts. In addition, F-based systems exhibited the most favorable energetics for monoatomic adsorption and electronic properties among the four substrates. Electronegativity also plays a key role on the destruction and formation of molecular structures during the adsorption of monatomic oxygen. Further work with adsorption of O₂ on these substrates is warranted to elucidate their potential to catalyze ORR.     

浅析二采区卤井生产周期

通过对二采区卤井生产周期及大修次数的统计，分析了地质构造、建井方式、生产方式、生产参数及井身结构等对生产周期的影响，总结出今后油垫建井的改进措施及二采区的生产原则。     

新型汽车前灯的技术进展

介绍陶瓷管金属卤化物灯，无汞金属卤化物灯，小功率球型短弧高压氙灯等新型汽车前灯的技术进展。较为详细介绍了这些新型灯的电压和启动特性、汞的替代物的选择及光电特性等。     

照明光学薄膜的开发和应用

照明用光学薄膜有许多种类，近来得到迅速的开发。本文介绍照明光学薄膜的制造技术和对它们的开发及应用。     

Coating of untreated polypropylene with halogen free aqueous materials

Substrates made out of polypropylene (PP) or it’s blends with ethylene-propylene rubbers (PP-EPR) which are typically used for exterior automotive parts are either pretreated before they are coated or the primary coating layer consists of or at least comprises a chlorinated polyolefin (CPO) as an adhesion promoter — most often applied as an organic solution. The presentation describes the approaches for the development of a halogen free aqueous adhesion promoter.

While chemical bonding via catalytic oxidation of the unactivated C---H bonds as well as via insertion of a nitrene into the C---H bonds proved to be ineffective, excellent adhesive strengths similar to those known from the state-of-art could be obtained via physical interactions with polyacrylic grafted polyolefins which have been applied as aqueous dispersions.

The correlation of adhesive strengths with process parameters and analytical results obtained from model systems leads to the assumption that the adhesion is effected by amphiphilic polymers interacting with the outermost polypropylene at the surface rather than by penetrating deeply into the substrate.     

Characterization method of photopolymerization kinetics of two dental composite resins using two types of light sources

The aim of this study was to characterize to photopolymerization curves of two dental composite resins (Z100^® from 3M ESPE Corp., and Tetric^® Ceram^® from Ivoclar Vivadent Corp.) according to the time exposure, the curing mode and the type of light source (halogen versus light emitting diode light curing units). The behavior and durability of composite resin do not depend only on their global shrinkage but also on their kinetic of polymerization which was studied with a mercury dilatometer. Four characteristics could be highlighted: the initial dilatation peak, the angle formed by the initial drop of shrinkage with the vertical axis, the angle formed by the secondary drop of shrinkage with the vertical axis and the intersection point between the two drops of shrinkage. The temperature rise was studied using a thermocouple to determine the position of the temperature peak in regard to the dilatation peak of the shrinkage curve. This is of interest for the clinical use of dental resin and light sources as well as curing procedures.