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4介绍含铅黄铜儿童仿真饰品标准物质的研制方法。以铜锭、锌锭、铅粒为原料,利用坩埚熔炼及模具加工制备黄铜儿童仿真饰品标准物质,采用电感耦合等离子体发射光谱法进行均匀性检验、稳定性检验和定值。从样品中随机抽取15份进行均匀性检验,经F检验表明在95%的置信区间内样品均匀性良好。在常温条件下,经过12个月长期稳定性试验考察,结果表明样品稳定性良好。铅含量定值结果为136.1 mg/kg,合成扩展不确定度为0.72 mg/kg(k=2)。该标准物质满足ISO Guide 35:2006技术要求,可用于黄铜儿童仿真饰品检测的方法校正和质量控制。 相似文献
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We show that an increase of memory of past strategy performance in a simple agent-based innovation model, with agents switching between costly innovation and cheap imitation, can be quantitatively stabilising while at the same time qualitatively destabilising. As memory in the fitness measure increases, the amplitude of price fluctuations decreases, but at the same time a bifurcation route to chaos may arise. The core mechanism leading to the chaotic behaviour in this model with strategy switching is that the map obtained for the system with memory is a convex combination of an increasing linear function and a decreasing non-linear function. 相似文献
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XRF分析黄金首饰中的主,次元素—修正比例常数法 总被引:3,自引:2,他引:1
本文创造了一套金合金标准,用XRF法分析黄金首饰中的主、次元素。发展了基体校正理论。进一步修正和完善了比例常数法的原理。汇编了一个专用的计算机程序。提出了一个新的分析方法。作者指出,本法比基本参数法更优越,有更好的发展前景。 相似文献
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Edward Cartwright 《International Journal of Game Theory》2007,36(1):119-135
We consider a learning dynamic in which players imitate and better reply. Sufficient conditions are provided for Nash equilibrium
play to emerge over time. The role of imitation in the learning dynamic is discussed through a series of examples. Most interestingly
we demonstrate how imitation can ‘help’ the emergence of Nash equilibrium where ‘more rational’ methods do not. 相似文献
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