Al2O3粒子填充电磁防护功能涂料研究

针对电子装备的电磁防护和高分子材料的抗静电问题，利用导电云母粉与醇酸树脂复合制备了一种浅色复合导电涂料，导电填料含量与涂层导电性能的关系曲线表明，当导电云母含量在60％~65％时，涂层具有良好的导电性能，表面电阻率在10^3Ω／cm。左右。尝试使用了导电云母与Al2O3组成的混合填料，重点探讨了Al2O3的用量对涂层导电性能的影响，结果表明，混合填料能够大大降低涂料体系的导电阈值，并考察了Al2O3的用量对涂层力学性能和环境性能的影响。     

导电混凝土的导电性能及影响因素研究进展

导电混凝土是具有导电、电热、电磁屏蔽等诸多特性或功能的复合材料,在道路融雪化冰、电气设备接地、结构健康监测以及电磁屏蔽等领域具有广阔的应用前景。导电混凝土应具有适宜的导电性能和电阻率稳定性,但是导电材料类型、形态和掺量以及导电混凝土含水率和环境温湿度等诸多因素都可能导致导电性能和电阻率稳定性降低,从而制约导电混凝土的工程应用。分类对比了常见导电材料的性能差异以及用不同导电材料制备的导电混凝土的导电性能差异,在此基础上,探讨了导电混凝土的导电性能和制备方法的研究现状,较为系统地分析了导电材料类型和掺量等因素对导电性能的影响,并提出了改善导电性能和电阻率稳定性的建议。     

金属导电短纤维提高Ni涂层导电性能研究

探索了金属导电短纤维提高电磁波屏蔽用Ｎｉ涂层导电性能的机制。结果表明，金属导电短纤维能大幅度地提高Ｎｉ涂层的导电性能，经分析是由于增大涂层中导电网络的密度所致。还对复合型涂层的屏蔽效能进行了理论预测。     

填料体系对导电硅橡胶导电-物理机械性能的影响及研究进展

填充型导电硅橡胶是一种同时拥有良好导电性能和物理性能的复合材料,在航空、电子等领域展示了广泛的应用前景。介绍了炭系、金属系、微/纳米体系、并用体系导电填料的添加对导电硅橡胶复合材料导电性能及物理机械性能的影响。指出了导电填料的种类、含量以及改性工艺对导电硅橡胶导电-物理性能的影响程度。阐述了研究进展状况,并对导电复合材料的未来研究方向提出了展望。     

导电聚合物及导电聚吡咯的研究进展

综述了导电聚合物的发展历史，导电聚合物的结构特征和基础性能、导电聚合物的类型及其合成方法；然后重点介绍了导电聚吡咯的研究进展。     

工艺参数对浅色复合导电涂料导电性能的影响

利用导电云母粉与醇酸树脂复合制备了一种浅色复合导电涂料,讨论了导电填料含量、偶联剂种类及含量、固化工艺以及涂层厚度等工艺参数对涂料导电性能的影响.结果表明,加入60%～65%导电云母粉,钛酸酯偶联剂NTG401用量为5%,涂层在50℃条件下烘烤2d,涂层厚度在120μm左右,涂料的导电性能较好,表面电阻率达到103Ω·cm-2.     

太阳能电池银导电浆料的研究进展与展望

银导电浆料广泛用于太阳能电池的正极导电材料。导电浆料的质量影响太阳能电池的转换效率和稳定性。综述了国内外银电子浆料的最新研究进展,并重点介绍了平均粒径在1μm的球形银粉和低松比片状银粉的制备及对银导电浆料电性能的影响,无铅玻璃粉的制备及性能影响因素,以及具有层次挥发性的有机载体的制备现状及各组分对太阳能电池正面银浆料导电性能的影响。最后展望了银导电浆料的发展方向,并提出了制备高分散性的球形银粉的方法,指出了太阳能电池导电浆料用玻璃熔体和有机载体的性能要求和发展方向。     

分散剂含量对碳系导电油墨导电性能影响的研究

目的研究分散剂的含量对碳导电油墨导电性能和表面性能的影响。方法以德谦W-920为分散剂,采用单因素法,保持碳导电油墨其他组分不变,改变分散剂的配置比例,制备不同组碳系导电油墨。最后通过SEM图表征墨膜的形貌。结果不同含量的分散剂对导电油墨的性能产生一定差异。在其他条件一定的情况下,随着分散剂比例的增加,导电性先上升后下降。结论分散剂的加入对导电油墨的性能起着重要作用,当分散剂的质量分数达到7%时,体积电阻率为3.01×10-2Ω·m,此时可以有效改善导电油墨的导电性和墨膜的规整性。     

电力系统接地网导电涂料的研究

论述了电力系统接地网因电化学腐蚀破坏而产生的危害,提出了采用导电涂料解决接地网腐蚀问题的方法。通过大量试验确定了导电涂料的配方,讨论了影响导电涂料性能的因素,并对其物理性能、耐蚀性能及导电性能进行了测试。     

碳黑/聚酯纤维非连续性导电行为研究

以熔体纺丝方法制备了碳黑/聚酯(CB/PET)导电纤维,分析了偶联剂对CB/PET纤维渗流阈值和T_g的影响,研究了碳黑含量与CB/PET纤维热性能和导电性能的关系。结果表明碳黑经偶联剂处理后,CB/PET纤维的渗流阈值和T_g均有所降低;碳黑含量对CB/PET纤维的性能影响显著,即随碳黑含量增加,CB/PET纤维的正效温度系数效应向高温移动;当碳黑含量为11%时,CB/PET纤维表现为较明显的正效拉力系数效应。     

Synchronized routing of active and passive means of transport

This paper addresses a routing problem where the fulfillment of transport requests requires two types of transport resources, namely, passive and active means of transport. The passive means are used for holding the cargo that is to be shipped from pickup to delivery locations. The active means take up the passive means and carry them from one location to another. Compared to classical vehicle routing problems, the additional challenge in this combined routing problem is that the operations of both transport resources have to be synchronized. In this paper, we provide a modeling approach for the joint routing of passive and active means of transport. We solve the problem by large neighborhood search meta-heuristics that utilize various problem-specific components, for example local search techniques for the routes of active and passive means. A computational study on a large set of benchmark instances is used for assessing the performance of the meta-heuristics.     

Differential multiplexing of fiber bragg gratings by means of optical time domain refractometry

A differential method of detection and multiplexing of signals from fiber Bragg gratings based on optical time domain reflectometry is developed. The method is based on probing of a system of gratings by means of short laser pulses and measurement of the power of the resulting reflected pulses by means of standard fiber-optic reflectometry. The proposed method may find extensive use in the area of monitoring of deformation and temperature distributions by means of fiber-optic sensors based on Bragg gratings.     

Sampling of uncertain probabilities at event tree nodes with multiple branches

When the uncertainty distributions of the conditional probabilities of a complete, mutually exclusive set of three or more branches at an event tree node are independently sampled, it is not possible that their values can both be constrained to add to 1.0, as they must, and also have their sample means converge as sampling size increases to the probabilities’ original means, as consistency with the initial point estimates that are these means demands. Complex sampling procedures may be applicable in special cases; e.g. when the uncertainty distributions are restricted to be betas that are elements of a Dirichlet distribution, and so have variances with restricted relationships to their means. Such procedures are not applicable in general and furthermore may not be practical in the analysis of large event trees. The expansion of a multiple node as a sequence of binary nodes with appropriate conditional probabilities, which is quite possible when only the point estimates are considered, has been attempted for uncertainty modeling but can be seen to be incorrect. Normalization of the sets of independent sample values of the launch probabilities is the most common procedure but obviously cannot provide the desired convergence. In this paper, a generally applicable procedure is derived for adjusting the sample values so that they correctly add to 1.0 and their means converge to the original means. The superiority of the procedure to common normalization is demonstrated in an illustrative application in a space launch vehicle risk analysis.     

若干积分不等式的加强形式

利用了初等方法,借助于调和平均与几何平均不等式以及Hoeldr不等式等初等不等式,得到Opial型,Poincare型,Sobolev型和Wirtinger型不等式的加强形式,并给出了不等式中常数的精确形式,其结果改进了Agarwal于1996年的主要结论。     

Integral solution of nonlinear magnetostatic field problems

This paper presents a procedure for using integrals to solve nonlinear magnetostatic field problems. An integral equation on magnetized volume, expressed in terms of magnetic field H or magnetization M, is discretized by means of edge elements on a tetrahedral mesh and solved numerically by means of a collocation method. The procedure approaches nonlinear by means of the fixed-point iterative technique. It sets up two different iterative schemes with complementary features. This paper gives details about implementation and presents and discusses results on some test cases     

产品设计中一种理性化的多属性多人评价方法

 讨论了多个属性评价结果的聚合以及多个评价者评价结果的聚合的理性化准则,分析了准线性权重聚合函数对这些准则的符合性,提出了基于准线性权重聚合函数的多属性多人评价方法,并进行实际应用,其结果表明该方法是合理的。     

Analysis of spatial arrangement of particles in thin foil of Al-Al4C3 material

TEM images of thin foils with quasi-globular particles are examined by means of two methods of spatial statistics. The spatial arrangement of particle reference points is described by means of quadrat count statistics and by polygonal method (the analysis of the Voronoi mosaic generated by patterns of particle reference points). A good agreement between the both approaches is found, the polygonal method is more sensitive and its results are more conclusive.     

Artificial intelligence techniques for prediction of the capacity of RC beams strengthened in shear with external FRP reinforcement

The prediction of the shear capacity of reinforced concrete beams retrofitted in shear by means of externally bonded FRP is very complex as demonstrate the studies carried out up to date. As alternative to the conventional methods two approaches based on artificial intelligence are proposed for the first time. Firstly, the use of neural networks as a means of predicting shear capacity without the need of using complex models and, secondly, the use of genetic algorithms as a means of determining suitably how the shear mechanism works. Predictions obtained with both approaches are compared to experimental values.