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51.
含钛高炉渣作为固体废弃物,国内存量巨大,且其中的钛组元难以提取,导致含钛高炉渣综合利用一直没有得到有效解决。针对当前含钛高炉渣利用率低、附加值低等问题,基于含钛高炉渣成分特点,通过选择性析晶(CaTiO3优势析出)、碱激发,制备出CaTiO3-多孔地质聚合物的复合材料。试验结果表明,析晶温度1 400 ℃、保温1 h能够促进CaTiO3的优势析出,而剩余氧化物以玻璃相形式存在。制备出的CaTiO3-多孔地质聚合物材料结合了CaTiO3高光催化活性与多孔地质聚合物比表面积大的优点,对亚甲基蓝具有优异的吸附效果,最大吸附量可达60.4 mg/g。在投加量为50 mg,2 h吸附、3 h光降解条件下,对亚甲基蓝去除率可达94.5%,在治理有机污染领域有良好的应用前景。  相似文献   
52.
The critical _d vahues ( _ ) of the γ/(γ+σ).γ/(γ+μ) and γ/(γ+γ') phase boundaries insome ternar alloy phase diagrams at various temperatures are calculated by averaging the _d values of sererai selected characteristic points at the phase boundaries.Approxmateequations for the temperature dependence of the critical _d of γ/(γ+σ).γ/(γ+μ) andγ/(γ+γ') phase boundaries are established.The accuracy of the analysis is discussed in detail.It is found for the first time that the average value of the bondorder _ at the phase boundaries ts also approximatelr a constant and therefore a criticalaverage bond order _ like - can be introduced for the analysts of phase stability  相似文献   
53.
高沸点溶剂法合成原乙酸三甲酯   总被引:2,自引:0,他引:2  
陈坤  成忠兴  胡传群  龙化云 《农药》2004,43(11):507-508,511
对低沸点溶剂法制备原乙酸三甲酯工艺进行了改进,比较了煤油、2-乙基己醇、氯苯、异佛尔酮、邻苯二甲酸二丁酯、乙二醇二丁醚等高沸点溶剂对反应的影响,筛选出最优高沸点溶剂煤油:研究了新反应体系的醇解pH值、溶剂的循环使用次数对反应的影响及溶剂循环损耗率,结果表明,醇解的最佳pH值为5.6;随着溶剂循环次数增加,原乙酸三甲酯收率从83.6%(1次)逐渐下降到76.7%(16次);溶剂次平均损耗率4.6%。实现了直接蒸馏产品,溶剂循环使用的新工艺。避免了旧工艺先蒸溶剂,后蒸产品,产品大量分解,收率低等缺点。  相似文献   
54.
本文介绍了基于化学统计热力学的熔渣模型,模型考虑到多元氧化物熔体由氧离子与其周围的阳离子组成的“晶胞”构成,并通过化学统计效力学的推导,利用少量的二元氧化物系热力学参数计算复杂的三元及多元氧化物系的热力学性质.利用此模型,计算了钢中生成的氧化物夹杂的成分,计算与实验结果一致.  相似文献   
55.
In the field of water quality management, it is vital to determine the main precursory anomalies from the precursor of intricate water bloom in the context of a given area. In this paper, a water bloom precursor analysis method, based on two direction singular rough set, was proposed. This approach was produced on the basis of the different sections and pre-water bloom of water bloom precursor anomalies and characteristic of elements transferred in singular rough set. For testing the validity of two direction singular rough set application in water bloom precursor analysis, Xiangxi River, which is one of the typical tributaries of Three Gorges Reservoir in China, was selected as study area. The result showed that compared with other indexes, pH and dissolved oxygen (DO) are the most valuable indicators of water bloom in the precursory anomalies. Furthermore, regarding with water bloom precursory anomalies in Xiangxi River, most of the nutrient loading and biological community are the key indicators. Hence, this method can determine the main precursory anomaly for water bloom in the study area, which provides powerful knowledge support to water quality specialists for them to comprehensively analyze precursory anomaly so as to find out its relationship with occurrence law of water bloom.  相似文献   
56.
吕坤  崔峰 《聚氯乙烯》2006,(4):29-32
通过大量试验分析了HPMC-E50和HPMC-F50在氯乙烯悬浮聚合中对PVC树脂的影响,从而确定了复合分散体系的质量分数以及分散剂的配比。结果表明,PVA和HPMC-E50复合分散体系的分散能力优于PVA和HPMC-F50复合分散体系;在悬浮聚合中,PVA和HPMC-E50复合分散体系与VCM的比例以0.05%~0.06%为宜;在PVA和HPMC-E50复合分散体系中,HPMC-E50所占比例以40%~60%为宜。  相似文献   
57.
Hyuk Wang  Buwon Kang 《Advanced Robotics》2014,28(19):1305-1320
Acquisition of the contact force at the instrument tip can enable better performance, e.g. transparency of the haptic feedback in the surgical robot systems. It is, however, difficult to measure the contact force directly due to technical limitations in attaching sensors to the tip of the instruments. This paper proposes a method to estimate the forces by installing the sensors away from the instrument tip. The proposed method employs specially designed mechanical parts of the slave robot, i.e. a slider cover plate for the z-axis translational force along the insertion direction, and docking clamps for the rotational pivot torques around the fulcrum point. Strain gauges are attached to specially designed places with enhancing shapes. The simulation results of the force estimation are presented to confirm the strain concentration area. The proposed method is validated with quantitative experimental results. Calibrated weights are determined upon the comparison of the strain value with a calibrated 6-axis force/torque sensor. The percentage error in the force calibration is about 5~8% calculated by the root mean square error (RMSE) of force-sensing performance. In addition, it can be computed by considering only the bending phase of each sensor although the hysteresis is observed from the calibration graph.  相似文献   
58.
摩擦副非正常磨损时将产生直径为几十微米的大金属磨粒。采用阻抗类方法检测磨粒时,要求传感器具有较高的灵敏度。为此,设计了差分结构的环状极板电容式传感器。应用电容/数字转换芯片AD7746将传感器的输出直接转换为数字信号,省去了前端复杂的信号调理电路,简化了设计,并且有效地降低了寄生电容和杂散电容的影响。实验表明:系统分辨率可以达到0.125 fF,极大提高了系统灵敏度。  相似文献   
59.
The high melt viscosity of polypropylene was studied by grafting bifunctional monomers, 1,6‐hexanediol diacrylate (HDDA) and tripropylene glycol diacrylate (TPGDA), onto homopolypropylene (HPP) and random ter‐polypropylene (RTPP) under electron‐beam irradiation. Creation of the high‐melt‐viscosity polypropylene was possible at low radiation dosage and low monomer content, under a prohibition of both radiation degradation and homopolymerization. TPGDA monomer was more effective in increasing the melt viscosity of HPP compared with RTPP, whereas HDDA monomer was more effective for enhancing the melt viscosity of RTPP. Such different effects of monomers on melt viscosity may arise from different monomer structures, namely, TPGDA has additional three methyl groups, but HDDA has no methyl groups. Electron‐beam radiation technology, on an increase of the melt viscosity, was much more effective in HPP than RTPP, when compared with virgin polymers. Modified RTPP and HPP with high melt viscosity were capable of foaming with numerous fine cells, of which the modified HPP with 1.5 mmol TPGDA and 0.5 kGy could create more spherical foam cells and its bending strength was 1.5 times more than that of the foamed RTPP. POLYM. ENG. SCI., 46:431–437, 2006. © 2006 Society of Plastics Engineers.  相似文献   
60.
Numerous indoor localization techniques have been proposed recently to meet the intensive demand for location-based service (LBS). Among them, the most popular solutions are the Wi-Fi fingerprint-based approaches. The core challenge is to lower the cost of fingerprint site-survey. One of the trends is to collect the piecewise data from clients and establish the radio map in crowdsourcing manner. However the low participation rate blocks the practical use. In this work, we propose a passive crowdsourcing channel state information (CSI) based indoor localization scheme, C2IL. Despite a crowdsourcing based approach, our scheme is totally transparent to the client and the only requirement is to connect to our 802.11n access points (APs). C2IL is built upon an innovative method to accurately estimate the moving speed solely based on 802.11n CSI. Knowing the walking speed of a client and its surrounding APs, a graph matching algorithm is employed to extract the received signal strength (RSS) fingerprints and establish the fingerprint map. For localization phase, we design a trajectory clustering based localization algorithm to provide precise real-time indoor localization and tracking. We develop and deploy a practical working system of C2IL in a large office environment. Extensive evaluations indicate that the error of speed estimation is within 3%, and the localization error is within 2 m at 80% time in a very complex indoor environment.  相似文献   
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