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The operation speed and integration degree of electronic components are getting higher and higher, which puts forward higher requirements for electronic packaging materials. Diamond is added to copper matrix composites to improve the thermal conductivity. The effects of cold spraying process and diamond addition on the microstructure and thermal conductivity of copper matrix composites are studied. The results show that the copper matrix composite prepared by cold spraying is a deformed strip copper layer. The change of cycle times has little effect on the microstructure, while the flattening rate of the deformed copper layer decreases as the carrier gas temperature increases. The diamond particles are uniformly distributed at the copper grain boundary after adding copper plated diamond powder, which are closely bound to the copper matrix. Increasing the temperature is conducive to increasing the thermal conductivity, while the change of cycle times has little effect on it. The addition of 20% diamond particles reduces the thermal conductivity, so the diamond content should be increased to play its role in thermal conductivity.

The impact of environmental regulation on technological innovation has been widely discussed in the academic circle. Based on the panel data of 403 Chinese manufacturing firms from 2010 to 2015, this paper explored the role of voluntary environmental regulation in technological innovation. The results showed the following: First, both voluntary environmental information disclosure and environmental management system certification had a positive effect on corporate innovation investment. Second, compared with the impact of environmental information disclosure, the impact of environmental management system certification on corporate innovation investment was more significant. Third, there was a significant positive interaction between environmental information disclosure and environmental management system certification. Finally, the effect of voluntary environmental regulation on corporate technological innovation in heavily polluting industries was stronger than that in lightly polluting industries.

Nowadays, firms spend a great deal of effort on Corporate Environmental Responsibility (CER) disclosure. From prospect theory, firms might disclose more CER information when they fail to achieve expected financial performance of the organization. We have constructed a CER disclosure index based on the “Guidelines for Environmental Information Disclosure of Listed Companies” issued by the Ministry of Environmental Protection of China in 2010. Using content analysis, we analyze 397 Chinese manufacturing Shanghai A-share listed firms from 2011 to 2017 (2090 firm-year observations) to investigate the relationship between corporate expected financial performance and CER disclosure. Our results show that, firstly, when the firm does not achieve the expected performance that is when the actual expectation is lower than the expected performance of the organization, the disclosure of corporate environmental responsibility increases; secondly, we have explored the moderating effect of industry categories; we have found that when firms fail to achieve the expected performance of the organization, light polluting firms are more inclined towards disclosing the environmental responsibility information than heavy polluting firms. Additionally, we have also studied the behavior of corporate environmental responsibility disclosure in the case of analysts expecting performance as a point of reference and got the same results.

The effect of Si additions on microstructure and mechanical properties of Al–4Cu–1.3Mg (wt%) alloy was investigated by microhardness measurements, TEM and HRTEM observations, mechanical properties test. The results indicate that the cubic σ-Al5Cu6Mg2 phases precipitate from matrix of the Al–4Cu–1.3Mg–0.3Si and Al–4Cu–1.3Mg–0.6Si alloys. The presence of σ-Al5Cu6Mg2 phases improved the tensile strengths of the alloys efficiently at elevated temperatures. The Al–4Cu–1.3Mg–0.9Si alloy following T6 peak ageing temper contained S′-Al2CuMg and β′-Mg2Si precipitates but slightly inhibited σ-Al5Cu6Mg2. The absence of σ precipitates leads to a loss of the tensile strengths of the alloy at elevated temperature.

Influence of silicon (Si) addition on aging precipitation behavior of an Al-4Cu-1.3Mg alloy was investigated by hardness measurements and TEM analysis. The results indicated that each of the Si-containing alloys exhibits an enhanced age-hardening response, a cubic phase, previously designated σ phase, was obtained. The σ phase was showed to be a (semi-)coherent and coplanar phase with the Al matrix, i.e.,{100}σ//{100}Al and σ// Al. In addition, S’ phase was observed. Si addition played an important role on the formation of σ phase. σ phases were observed in the Si containing alloy for all the aging conditions studied but was absent in Si-free alloy. The content of Si significantly influenced the volume fraction of σ phase in the alloy. Prolongation of aging time will be conducive to precipitation of a greater number of σ phases.

We select reverberation chamber for this study, with using method of FDTD, combining with parallel computing to simulate the interior distribution. From the simulation results, we analyzed the mesh generation of parallel treatment and the calculation efficiency.