重铬酸钾滴定法测定金属化球团中氧化亚铁含量

确定了试样以盐酸分解,重铬酸钾滴定法测定金属铁和亚铁合量,再减去金属铁含量,通过换算得到氧化亚铁含量。通过对不同条件下的试验优化,建立了重铬酸钾滴定法测定金属化球团中氧化亚铁含量试验方法,其测定结果的相对标准偏差为0.41%~0.94%,回收率大于96.0%。     

Efficient MgO-doped CaO sorbent pellets for high temperature CO2 capture

Novel MgO-doped CaO sorbent pellets were prepared by gel-casting and wet impregnation. The effect of Na⁺ and MgO on the structure and CO₂ adsorption performance of CaO sorbent pellets was elucidated. MgO-doped CaO sorbent pellets with the diameter range of 0.5-1.5 mm exhibited an excellent capacity for CO₂ adsorption and adsorption rate due to the homogeneous dispersion of MgO in the sorbent pellets and its effects on the physical structure of sorbents. The results show that MgO can effectively inhibit the sintering of CaO and retain the adsorption capacity of sorbents during multiple adsorption-desorption cycles. The presence of mesopores and macropores resulted in appreciable change of volume from CaO (16.7 cm³∙mol⁻¹) to CaCO₃ (36.9 cm³∙mol⁻¹) over repeated operation cycles. Ca2Mg1 sorbent pellets exhibited favorable CO₂ capture capacity (9.49 mmol∙g⁻¹), average adsorption rate (0.32 mmol∙g⁻¹∙min⁻¹) and conversion rate of CaO (74.83%) after 30 cycles.     

基于小波变换的球团矿图像边缘检测

球团粒径及其分布是衡量球团矿质量的重要指标。球团矿图像的边缘检测对基于数字图像处理的球团粒径自动检测具有重要意义。但是，由于成像中的噪声及球团图像的无背景等特点，使得球团图像的边缘检测比较困难。本文利用小波变换系数模局部极大值来检测球团图像的边缘，取得了较好的效果。     

链篦机-回转窑铁矿氧化球团干燥预热工艺参数研究

利用程潮铁矿自产磁铁精矿,在膨润土添加量为1.0%~1.2%时,润磨后造球。通过模拟链篦机装置试验,研究了链篦机-回转窑氧化球团生产工艺中链篦机料层高度、鼓风干燥热风温度、抽风干燥热风温度、预热热风温度及风速(工况)等预热工艺参数。在此干燥预热工艺条件下,链篦机干球经回转窑焙烧固结后,球团矿抗压强度2828N/个,转鼓指数(+6.3mm)93%,耐磨指数(-0.5mm)3.53%,FeO<1%,成品球质量达到了优质球团质量的要求。     

大晶粒UO2燃料芯块堆内试验组件的研制

为了开发高性能的压水堆燃料,研制了大晶粒燃料芯块。试验燃料芯块具有高的235U富集度、小直径和大晶粒尺寸的特点。通过堆内辐照试验可以对不同制造工艺的燃料芯块进行评价和筛选,以便确定燃料制造工艺。为了在中国原子能科学研究院池式研究堆中随堆考验,设计了一种试验组件,包含四根双包壳的燃料棒。双包壳燃料棒是在外包壳内装入两根单包壳燃料棒。试验组件直接由反应堆一次循环水冷却,不设专门的冷却回路。试验组件上安装了多种堆芯测量传感器,包括燃料中心温度热电偶、自给能中子探测器和冷却剂出、入口温度热电偶,可以在线监测燃料试验参数。描述了大晶粒UO2燃料芯块的研制、试验燃料组件的研制和检验。     

微丸压片法制备单硝酸异山梨酯缓释片

目的制备单硝酸异山梨酯微丸缓释片,考察体外释放度。方法制备单硝酸异山梨酯微丸,包衣后压制缓释片,通过考察不同包衣材料、丸芯大小、压片压力及包衣增重对缓释片体外释放度的影响,筛选并确定最佳处方。结果按优化处方制备的单硝酸异山梨酯缓释片体外释放度与市售单硝酸异山梨酯缓释片体外释放度一致。结论制备的制剂处方合理,工艺可行,体外释放度与市售片一致。     

A Comparison of Pellet Quality from Straight-grate and Grate-kiln Furnaces

Both straight-grate and grate-kiln furnaces have been accepted in the iron ore industry. Both are considered to be roughly equal when comparing overall costs and expenses versus the final product production rate. However, the product quality of these two systems is not equal. This is shown by critically examining the dust generation of pellets from several facilities. The dustiness of pellets is associated with overall pellet strength, and is an important quality measure of fired pellets on its own. A clear distinction between the dustiness of grate-kiln and straight-grate fired pellets is established. We conclude that grate-kiln-cooler systems provide superior pellet quality, but at the cost of some pellet production rate.     

绞股蓝皂苷微丸的制备工艺

研究绞股蓝皂苷微丸的制备工艺。以挤出频率、滚圆频率、滚圆时间为考察因素,以微丸的圆整度为评价指标,利用单因素法研究制备微丸的最优工艺条件。采用挤出滚圆法制备空白微丸;采用流化床法制备绞股蓝皂苷微丸。并对微丸的粉体学性质和体外释放度进行测定;用红外光谱法、X-射线粉末衍射法、扫描电子显微镜法对其进行表征。结果显示,制备微丸的最佳工艺参数为挤出频率30 Hz、滚圆频率50 Hz、滚圆时间4 min。采用流化床底喷上药包衣法制备的绞股蓝皂苷微丸体外释放度为95.98%,符合药典规定;脆碎度为0.90%;圆整度为0.80,表面较为光滑;堆密度较好、大小均匀;休止角为38.70°,流动性较好。电镜、红外、X-衍射等表征结果表明微丸圆整,绞股蓝皂苷分布均匀。利用挤出滚圆-流化床包衣法制备绞股蓝皂苷微丸,该工艺简便易行,可工业化生产。     

GLCM based extraction of flame image texture features and KPCA-GLVQ recognition method for rotary kiln combustion working conditions

According to the pulverized coal combustion flame image texture features of the rotary-kiln oxide pellets sintering process,a combustion working condition recognition method based on the generalized learning vector(GLVQ) neural network is proposed.Firstly,the numerical flame image is analyzed to extract texture features,such as energy,entropy and inertia,based on grey-level co-occurrence matrix(GLCM) to provide qualitative information on the changes in the visual appearance of the flame.Then the kernel principal component analysis(KPCA) method is adopted to deduct the input vector with high dimensionality so as to reduce the GLVQ target dimension and network scale greatly.Finally,the GLVQ neural network is trained by using the normalized texture feature data.The test results show that the proposed KPCA-GLVQ classifer has an excellent performance on training speed and correct recognition rate,and it meets the requirement for real-time combustion working condition recognition for the rotary kiln process.     

PMC精矿粉细磨粒度对球团质量的影响

研究了PMC精矿粒度对球团质量的影响, 结果表明：PMC矿粉粒度由0.074 mm变细至0.044 mm, 球团落下强度由3.90次/0.5 m增大到4.25次/0.5 m, 抗压强度由7.42 N/个增大到7.62 N/个, 成球率由94.02%下降到87.80%, 爆裂温度由460 ℃降到390 ℃。当预热时间15 min、预热温度925 ℃、焙烧温度1 300 ℃、焙烧时间10 min时, PMC0.044精矿粉球团的抗压强度较PMC0.074精矿粉球团的抗压强度有显著提高。