排序方式: 共有61条查询结果,搜索用时 31 毫秒
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洗涤剂中磷酸盐对水域的污染危害及防治对策 总被引:1,自引:0,他引:1
通过对洗涤剂中磷酸盐流入江河湖海引起赤潮污染造成巨大经济损失的分析。提出只有通过政府等部门立法洗涤剂禁磷,才是能决磷酸盐污染的最佳方法。并介绍了新型无磷助洗剂层硅是替代三聚磷酸钠的最佳产品。 相似文献
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介绍了一种由菱镁矿生产特种硅钢级氧化镁的工艺,讨论了轻烧粉乳液浓度、碳化时间、煅烧温度等反应条件对硅钢级氧化镁质量的影响,并得出较佳的工艺条件。 相似文献
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本文在灰铸铁的焊接性能差的基础上,对其进行分析,如何控制及防止不利焊接因素的产生,从白口和淬硬组织及冷热裂纹等方面,对灰铸铁的焊接性能进行了更深入的分析,最终达到对灰铸铁焊缝的有效施焊。 相似文献
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在混凝土中,最能影响其耐久性的因素就是钢筋的腐蚀。本文通过对某工程的钢筋混凝土结构腐蚀进行研究,介绍了钢筋混凝土结构的防腐问题,提出一系列切实可行的处理方法。 相似文献
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Steven T. Walsh Author Vitae Robert L. Boylan Author Vitae Author Vitae Al Paulson Author Vitae 《Technological Forecasting and Social Change》2005,72(2):213-236
The resource-based perspective has done much to identify idiosyncratic firm attributes that may be a principal source of competitive advantages. Unfortunately, there has been little systematic industry evidence to support the strategic importance of core competence, nor has there been much work on the temporal or cumulative nature of core capabilities within an industrial setting. Further, little or no research has been performed demonstrating how the advent of technological discontinuities or disruptive technologies plays a part in creating epochs in technology competency development and the roadmap of an industry. In this study, we analyze the evolutionary and cumulative nature of core capabilities and their interactions with technological discontinuities from a market-driven perspective. We have studied the evolution of 167 firms through the 50-year history of the semiconductor silicon industry. Over time, there were several structural shifts in the necessary competencies through the advent of disruptive technologies. In the last 30 years, however, the change in the required competencies has been more cumulative in nature. We summarize this in a roadmap detailing the epochs in the semiconductor silicon industry. 相似文献
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本文针对公路工程中经常遇到的不良路基土的常用固化剂水泥从固化土改良机理、物理力学性质的变化等方面进行阐述。同时指出了水泥固化剂的不足,建议研究开发新型、高效土壤改良材料,并深入探讨其改良机理。 相似文献
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利用模糊贝叶斯网络模型和小波时间序列模型进行高炉铁水含硅量预报,预测命中率(预测值与实际值误差±0.1)分别为84%和76%,基本反映高炉生产实际.对比分析两个模型的预报结果以及高炉内部反应机理的特点,结合两个模型优势,提出组合预报模型,把预报命中率提高到92%,具有生产应用价值. 相似文献
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粉煤灰制备白炭黑的探索性研究 总被引:22,自引:0,他引:22
初步探讨了用工业固废粉煤灰制备白炭黑的方法.依此法,粉煤灰经激活、酸浸、陈化、除杂等工艺,制备出SiO2纯度达91.7%的白炭黑,其化学式为SiO2·1/7H2O,品质标准符合HG/T3601. 相似文献