EVA-g-GMA的制备及其对PLA/PHBV共混物性能的影响

通过熔融聚合法先制备了乙烯-醋酸乙烯酯接枝甲基丙烯酸缩水甘油酯(EVA-gGMA),采用红外光谱仪和核磁共振对EVA-g-GMA的结构进行了表征。然后将不同质量分数的EVA-g-GMA加入到聚乳酸/聚(3-羟基丁酸酯-co-3-羟基戊酸酯)(PLA/PHBV)共混物中,对共混物的性能进行研究。结果表明:GMA成功接枝到EVA上,随着EVA-g-GMA加入量的增加,PHBV与PLA的Tg升高,结晶度逐渐下降;分散相在PLA基体中的分散逐渐均匀,粒径减小,相界面渐渐模糊;在EVA-g-GMA加入后,共混物粘度升高,断裂伸长率和冲击强度分别可达290.9%和43.5KJ·m-2,三元共混物的水蒸气阻隔性相对于PLA/PHBV略有下降。综合考虑各种因素,EVA-g-GMA的加入使得PLA/PHBV的整体性能得到极大改善。     

半固态触变挤压对ZA27合金组织和力学性能的影响

通过与常规铸造方法的比较,研究半固态触变挤压对ZA27合金变质、热处理组织和力学性能的影响。结果表明:半固态挤压态合金的密度较铸态合金提高了3%,合金经Sc变质或者半固态挤压都获得了细小而均匀的近似球状组织,而Sc变质结合半固态挤压的球状组织具有最高的圆整度;经T6热处理的半固态挤压合金由细小的初生α相和共析(α+η)组织组成,说明半固态挤压可促进ε相溶解、减少三元共晶(β+η+ε)组织的含量。力学性能测试表明,ZA27合金经半固态挤压+Sc变质+T6热处理后其抗拉强度,伸长率和布氏硬度分别达到586.01MPa,17.57%及171HB。     

Preparation of Porous Silver Nanowires-Melamine Formaldehyde Hybrid Composite Materials and Their Electromagnetic Shielding and Flame-Retardant Properties

Along with the booming development of communication technology and electronic equipment, higher requirements of flame-retardant and EMI shielding performances for electromagnetic interference (EMI) shielding materials are put forward. Herein, the ultralight and porous silver nanowires (AgNWs)-melamine formaldehyde (MF) hybrid composite with unique micro-/nanostructure is developed by a facile dip-coating method, which uses the AgNWs as 1D conductive coating and MF foam (MF foam) as 3D skeleton template. Benefiting from the unique porous micro-/nanostructure, the resultant hybrid composite displays low density, excellent EMI shielding performances, and superior flame-retardant property. The EMI shielding effectiveness (SE) and specific EMI SE (SSEt) of the hybrid composite in X-band (8.2–12.4 GHz) can be up to 77 dB and 26971.4 dB cm⁻² g⁻¹, respectively. At the same time, the hybrid composite also passes the vertical burning test and shows an increased LOI value of 40.6%. The combination of flame-retardant and EMI shielding performances for EMI shielding materials makes the AgNWs-MF hybrid composite great application potential in civil and military fields. This work provides a new guide for the design of multifunctional high-performance EMI shielding materials.     

马钢2500m~3高炉炉渣的冶金性能

在目前的原燃料条件下,为保证马钢2500m3高炉炉渣具有良好的流动性和较高的脱硫能力,炉渣的CaO／SiO2应控制在1．05至1．15之间,炉渣温度不低于1450℃．     

全固态裸露式Ag／AgCl参比电极的研制及应用

该文报道了一种树脂接界全固态裸露式Ag／Agcl参比电极,勿需电镀氯化,制备工艺简单,性能稳定,是对电解型Ag／AgCl参比电极的一大改进。可代替饱和甘汞电极作为通用型参比电极,同时可减少汞对环境所造成的二次污染,在温度大于75℃时仍能保持良好性能,突破了甘汞电极的局限。     

Virtual rights? Property in online game objects and characters

The new industry of Massively Multi-Player Online Role-Playing Games (MMORPGs) brings together two sets of fictions: the interactive stories of shared computer games and the legal devices of intellectual property. In these virtual worlds, scarcity need not exist, but players tend to prefer the competition it creates. This leads to the development of property rights within the game world and players trading real money for virtual objects, ‘land’ and characters. This new phenomenon brings with it familiar legal problems such as theft, fraud and ownership disputes. Game creators also challenge the right of the players to claim ownership outside the game world. The volume and value of the items traded make real money trading an important area of current interest for intellectual property lawyers. Something is being traded, but does it fit neatly into existing conceptions of property rights and who owns it? Analysing the novel problems that result from various theoretical perspectives (utilitarianism, labour-desert theory and personality theory) leads to the conclusion that with time, we will see the development of property rights for players in online games. This connects with a growing understanding that the traditional conception of copyright law dealing with creative work generated by the solitary author is becoming less appropriate in the new creative spaces that information and communications technology brings, where individuals are both consumer and producer. In virtual worlds, new forms of intellectual property, and perhaps even new rights, are taking shape.     

一种改进的GA变异算子及其数学分析

提出了一种改进的GA变异算子,并对其有效性作了数学分析。实例表明,该算子能改善GA的收敛性能。     

Distributed Symbolic Bounded Property Checking

In this paper we describe an algorithm for distributed, BDD-based bounded property checking and its implementation in the verification tool SymC. The distributed algorithm verifies larger models and returns results faster than the sequential version.The core algorithm distributes partitions of the state set to computation nodes after reaching a threshold size. The nodes proceed with image computation on the nodes asynchronously. The main scalability problem of this scheme is the overlap of state set partitions. We present static and dynamic overlap reduction techniques.     

新型乙烯基聚酯树脂的开发

本文主要介绍了乙烯基聚酯树脂的性能及应用.     

我国超高分子质量聚乙烯纤维的检测手段及发展现状

根据国内主要超高分子质量聚乙烯纤维制造商产品的测试结果,论述了国产该纤维的主要性能及其与国外同类产品的质量差距,论述了目前我国各生产厂家及相关检测机构在强度、模量、断裂伸长、耐磨性、蠕变率、分子质量等纤维主要性能测试中存在的问题,提出了解决建议,同时指出了我国在超高分子质量聚乙烯纤维应用方面与国外的差距．