微波辐照载锰活性焦脱硝实验研究

通过在活性焦上负载Mn2O3实现微波低功率（200 W）高效脱除NO。实验发现,经硝酸氧化处理和负载Mn2O3,活性焦表面的羰基和羧基等含氧官能团含量增加,微波辐照使得活性焦比表面积和微孔体积大幅增加,为反应气体在活性焦表面吸附提供丰富的表面活性位,有利于NO的脱除。硝酸处理后的活性焦负载Mn2O3,脱硝效率能稳定达到85%以上,负载Mn2O3使得微波诱导的放电强度增强,等离子体浓度增加,更多的稳定态NO分子被转化为激发态,促进了NO还原反应的发生。     

烟气喷淋脱碳数值模拟及其特性分析

针对烟气喷淋脱碳,采用欧拉-拉格朗日法建立了耦合气液流动、热质传递及化学反应的三维数值模型,并基于热力一致性简化模型中的热力学表达,以降低计算成本。模型验证表明,预测结果与实验结果吻合良好。基于该模型考察了塔内气液流动、热质传递及CO2吸收等特性。结果表明:喷淋方式对塔内气液分布、温度分布及CO2吸收有重要影响;向下喷淋将卷吸喷嘴周围烟气沿塔中部向下流动,与新入烟气存在强烈的掺混行为,并造成液滴在塔中部集聚;气液温度分布及H2O气相体积分数分布有较高的关联性,汽化潜热占热交换总量的64%;传质阻力集中在液侧,比气侧高2个数量级;通过改变喷淋方向可以减小液滴分布不均匀性,将脱碳效率从38.3%提升至49.6%。     

生物质直燃发电大气污染物超低排放技术路线分析

总结了生物质燃料与煤的元素含量的差异,分析了生物质锅炉积灰、结渣、腐蚀的机理,梳理了生物质锅炉的烟气特点,并对选择性非催化还原脱硝技术、选择性催化还原脱硝技术、湿法脱硫技术在生物质电厂应用的局限性进行了讨论和总结。结果表明:固态高分子脱硝和催化剂脱硝脱硫均需特殊催化剂或脱硝剂,属于专利产品,运行成本高;氧化脱硝技术属于氧化吸收反应,产生易溶于水的硝酸盐,部分地区禁止采用该技术;陶瓷催化滤管一体化脱除技术运行维护简单,锅炉过氧燃烧可提高燃烧效率,延长空气预热器使用寿命,而且没有脱硫废水、烟囱防腐、白色烟羽等相关问题,适用于生物质锅炉硫、尘、硝超低排放。     

Johnson-Cook dynamic constitutive relationship for TC 16 titanium alloy

The true stress--strain curves of TC16 alloy with a wide range of strain rates were investigated under uniaxial quasi-static tension and uniaxial dynamic compression with the lnstron 8032 test machine and the split Hopkinson bar respectively. The results indicate that the true stress increases with increasing strain rate, while decreases with increasing temperature. Under the 105 s^-1 high strain rate and temperature higher than 673 K, the true stress would even be less than that under quasi-static condition. A new method incorporating TCl6＇s stress strain curve developing item was proposed to determine the coefficients in J-C model easily and to avoid the estimation of the adiabatic temperature rising. The Johnson-Cook dynamic constitutive relationship for TC16 was obtained for the first time. Good agreement was obtained between the model prediction and the experimental stress--strain curves for TC16 under both quasi-static and dynamic loadings.     

TA2／A3爆炸复合界面微观断裂机制的SEM原位研究SCIEI

借助ＳＥＭ对ＴＡ２／Ａ３爆炸复合界面（包括细小波状界面，中波界面及具有再入射流熔块的大波界面）的微观断裂机制进行了动态研究。结果表明，爆炸复合界面微观断裂机制是：微裂纹在波头夹杂或再入射流熔块内及熔块和基体界面处萌生，并在裂尖应力场作用下沿与外载垂直方向扩展。同时，沿ＴＡ２／Ａ３界面产生微裂纹并在外载作用下，相互连接而扩展。     

稀土镧、钇对蓝色氧化钨氢还原的影响

借助于ＳＥＭ、Ｘ射线衍射技术及ＩＰＰ粉末粒度仪等系统地研究了稀土镧、钇对蓝色氧化钨（ＢＯ）氢还原的影响。结果表明：稀土元素镧、钇在蓝色氧化钨的还原钨粉中以氧化物及钨酸盐形式存在；还原后所得的钨粉颗粒大多为规则形状的多面体；稀土镧、钇和铝相似，强烈地抑制ＢＯ氢还原钨粉颗粒的长大，而且钇的作用更为显著。     

超声波提取-吸附分离-气相色谱法测定茶叶中农药残留

将超声提取-吸附分离的预处理技术用于气相色谱法检测茶叶中的农药残留。对超声波提取条件和吸附分离柱（自制）的结构进行了优化。建立了茶叶中有机磷类和菊酯类农药残留的气相色谱法定量测定的方法。进行了3个质量分数的标准添加，甲胺磷、乐果、联苯菊酯、氯氟氰菊酯、溴氰菊酯的回收率相应为75％～95％、87％～110％、89％-102％、88％-105％、80％-93％，相对标准偏差为2．6％．4．8％，检出限为0．005-0．02mg／kg。该方法速度快、灵敏度高、重现性好。     

半监督学习在不平衡样本集分类中的应用研究

在对不平衡样本集进行分类时容易产生少数类样误差大的问题,而目前半监督学习中的算法多数是针对未有明显此类特征的数据集。针对一种半监督协同分类算法在该问题上的有效性进行了研究。由于进一步增强了分类器差异性,该算法在理论上对不平衡样本集具有良好的分类性能。根据该算法建立分类模型,利用其对桥梁结构健康数据进行分类实验,与Tri-Training算法的结果比较表明,该算法对不平衡样本集具有良好的适用性,从而验证了上述算法的有效性。     

Decarburization rate of RH refining for ultra low carbon steel

The decarburization behaviors of ultra low carbon steel in a 210-t RH vacuum degasser were investigated under practical operating conditions.According to the apparent decarburization rate constant (KC) calculated by the carbon content in the samples taken from the hot melt in a ladle at an interval of 1-2 min,it is observed that the total decarburization reaction period in RH can be divided into the quick decarburization period and the stagnant decarburization period,which is quite different from the tradit...     

Particle simulation of the failure process of brittle rock under triaxial compression

In order to investigate the failure process of brittle rock under triaxial compression through both experimental and numerical approaches, the particle simulation method was used in numerical simulations and the simulated results were compared with those of the experiment. The numerical simulation results, such as fracture propagation, microcrack distribution, stress-strain response, and damage patterns, were discussed in detail. The simulated results under various confining pressures (0-60 MPa) are in good...