啮合同向双螺杆挤出机偏心六棱柱元件混合性能的研究

提出了一种新型的偏心六棱柱元件,并对其混合流场进行三维非牛顿等温模拟;比较了六棱柱元件和偏心六棱柱元件的混合性能,同时通过添加10 %（质量分数,下同）玻璃纤维增强的聚碳酸酯共混改性实验,对两者的混合效果进行了评估和表征。结果表明,由于流场中引入了明显的拉伸流动,偏心六棱柱的分散和分布混合能力优于六棱柱元件,所制备的玻璃纤维增强材料的韧性提升超过40 %,并且热变形温度提高了7 ℃。     

金属元素掺杂改性的纳米TiO2光催化材料研究进展

根据近年来金若元韶掺杂改性TiM2光催化技术的研究成果,对金属元素改性纳米TiO2光催化剂进行了详细地综述.最后,提出了多种金属元素、以及金属元素与非金属元素、多种金属元素与多种非金属元素一起掺杂改性TiO2,实验结果证明该方法是行之有效的,也将是今后一个重要的研究方向,并还存在着巨大的研究空间.     

西部煤中环境敏感性痕量元素的燃烧迁移行为

应用仪器中子活化( INAA)、电感耦合等离子体原子发射光谱( ICP- AES)和原子吸收光谱( AAS)对我国西北部五个电厂原煤、底灰和飞灰中环境敏感性痕量元素的含量进行了系统测定,通过不同电厂原煤与燃烧产物中痕量元素的含量变化特征,揭示了痕量元素在不同燃烧产物中的相对富集规律.以痕量元素在不同燃烧产物中的相对富集系数为评价标准,建立了燃烧产物中痕量元素的分配模型.结合痕量元素的原始赋存状态,总结了痕量元素燃烧的迁移富集机理和环境效应.     

DRYING OF MOCK SPENT NUCLEAR FUEL ELEMENTS

Spent nuclear fuel elements are stored in underwater cooling pools until the elements can be safely handled and prepared for interim dry storage. The fuel was intended for short-term storage in water before it was to be reprocessed. However, the fuel will no longer be reprocessed, and extended storage in water has caused many of the aluminum-clad elements to degrade, exposing the uranium fuel. In addition, sludge, comprised of corroded aluminum and sediment, has accumulated in and around the fuel plates. The water in the sludge must be removed before the spent fuel elements can be placed in dry storage. Experiments have been performed on mock spent fuel elements with simulated corrosion product applied between the plates. A series of vacuum and heating cycles were used to dry the elements, and a mixture of clay and aluminum oxide was used to simulate corrosion products on the elements.

The procedures used in the experiments were determined to be adequate to dry the mock spent fuel elements, and the temperature behavior of the simulated corrosion product within the fuel elements could be used to determine when the element was dry. On plates where areas of wet simulant were found, a sharp drying front was observed that separated the wet and dry parts of the simulated corrosion product. The drying front propagated inward towards the center of the mock fuel elements over time.     

水溶性叶面肥对豇豆产量的影响

使用8个不同配方叶面肥在豇豆营养生长阶段喷施3次,调查叶面肥对豇豆产量的影响。结果表明,与对照相比,喷施4.3%黄腐酸叶面肥处理增产67.0%;8%黄腐酸＋氮磷钾增产57.1%;大量元素＋微量元素[（N＋P2O5＋K2O≥23%9∶6∶8）＋（F e＋B＋Z n≥1%）]的增产48.2%;4%腐植酸钾＋大量元素＋微量元素[（N＋P2O5＋K2O≥23%9∶6∶8）＋（Fe＋B＋Zn≥1%）]增产43.2%（添加腐植酸钾不利于提高产量）;3%腐植酸钾＋维生素＋尿素＋硫酸钾≥7%增产40.8%;大量元素＋微量元素[（N＋P2O5＋K2O≥35%12∶10∶13）＋（F e＋B＋Z n≥0.6%）]增产39.5%;3%腐植酸钾＋大量元素＋微量元素[（N＋P2O5＋K2O≥35%12∶10∶13）＋（F e＋B＋Z n≥0.6%）]增产33.7%;4%腐植酸钾增产15.9%。黄腐酸增产效果最明显,微量元素增产效果比大量元素明显,腐植酸钾增产幅度较低,腐植酸钾＋大量元素＋微量元素处理的增产效果低于大量元素＋微量元素处理。     

DRYING OF MOCK SPENT NUCLEAR FUEL ELEMENTS

Abstract

Spent nuclear fuel elements are stored in underwater cooling pools until the elements can be safely handled and prepared for interim dry storage. The fuel was intended for short-term storage in water before it was to be reprocessed. However, the fuel will no longer be reprocessed, and extended storage in water has caused many of the aluminum-clad elements to degrade, exposing the uranium fuel. In addition, sludge, comprised of corroded aluminum and sediment, has accumulated in and around the fuel plates. The water in the sludge must be removed before the spent fuel elements can be placed in dry storage. Experiments have been performed on mock spent fuel elements with simulated corrosion product applied between the plates. A series of vacuum and heating cycles were used to dry the elements, and a mixture of clay and aluminum oxide was used to simulate corrosion products on the elements.

The procedures used in the experiments were determined to be adequate to dry the mock spent fuel elements, and the temperature behavior of the simulated corrosion product within the fuel elements could be used to determine when the element was dry. On plates where areas of wet simulant were found, a sharp drying front was observed that separated the wet and dry parts of the simulated corrosion product. The drying front propagated inward towards the center of the mock fuel elements over time.     

ICP-AES法测定Beta沸石中常量和微量组分

研究了沸石分子筛中主要和微量组分电感偶合等离子体发射光谱（ICP-AES）测定方法。考察了溶样酸度、仪器条件对测定的影响,以及共存元素间的干扰情况,优化了工作条件。实验结果表明,常量元素相对标准偏差（RSD）<1%,回收率为98.6%;杂质元素RSD<7%,回收率为85%~112.1%。     

混合元件数对SK型静态混合器流场特性的影响

以SK型静态混合器为对象,运用激光多普勒测速仪对混合器内流场进行测量分析,研究混合元件数对混合器内速度分布和湍动性能影响。结果表明：在扭旋叶片作用下,流体在混合器内的速度会重新分布,湍动会被强化,这一过程主要在前3个混合元件中实现,且湍动逐渐增加,但增加速度逐渐减弱,第1个混合元件强化作用最为显著,进入第4个混合元件后基本达到稳定;当混合叶片数量超过3个以后,对流体湍动的强化基本达到混合器强化能力的极限,继续增加元件数量不能提高流体的湍动程度,但可以维持这种湍动。     

320MW燃煤电厂痕量元素的分布、脱除及排放特性

燃煤电厂痕量元素的排放已经引起了世界的广泛关注。在一台配置选择性催化还原（SCR）+静电除尘器（ESP）+湿法脱硫装置（WFGD）的320MW燃煤电厂上进行了12种痕量元素（Cr、Mn、Co、Ni、Cu、Zn、As、Mo、Cd、Sb、Ba、Pb）排放特性的实验研究,使用了US EPA Method 29对4个测点烟气痕量元素进行同时取样,考察了痕量元素在电厂中的分布、协同脱除以及在烟囱中的排放。结果表明：锅炉、SCR、ESP、WFGD和整个系统的痕量元素质量平衡率均在可接受的范围内。这12种痕量元素主要分布在底渣和飞灰中,分别占据底渣、ESP灰、WFGD脱除及烟囱排放痕量元素总量的1.90%～27.6%和72.3%～98.0%,然而,它们在烟囱和被WFGD脱除的部分所占比例较少,两者之和仅占0.11%～0.66%。ESP和WFGD对烟气痕量元素的脱除率分别为99.39%～99.95%和40.39%～78.98%,SCR+ESP+WFGD对烟气痕量元素的总体脱除率为99.79%～99.99%。ESP对痕量元素较高的脱除效率是APCDs系统具有较高的协同脱除效率的主要原因。烟囱排放的痕量元素浓度及排放因子分别为0.01～12.88 μg·m^-3和（0.002～4.57）×10^-12 g·J^-1。应进行更多的燃煤电厂痕量元素排放的研究,以便为中国燃煤电厂痕量元素的排放预测模型的建立以及相关标准的制定提供参考。     

Wettability control of laser textured SiC surfaces using additive elements

Wettability control of laser textured SiC ceramic surfaces through the addition of pure elements was studied in this work. A correlation analysis between the elements C/O/Si/B/Al/Fe and the contact angle demonstrates that elements C/O/Si/B are all highly correlated with the wettability. The correlation of elements Fe/Al with the contact angle is relatively lower. Because elements C/Si are inherent elements in a SiC material, element O is derived from oxidation, and element B is added along with the additives during the sintering process. A more hydrophilic SiC surface was obtained by controlling the addition of element B.     

ICP-MS等离子体质谱法测定稀散元素矿石中重金属元素含量

稀散元素矿石经HCl-HNO_3-HF-HClO_4消解后,用电感耦合等离子体质谱法(ICP-MS)测定重金属元素Ni、Cu、Zn、Cd、Sb、Pb、Bi的含量。该方法检出限为0.004~0.51μg?g~(-1),相对标准偏差(RSD,n=6)为1.08%~4.67%,分析结果准确可靠,是测定稀散元素矿石中重金属含量的一种较好的分析方法。     

ICP-MS法测定注射用双黄连(冻干)无机阳离子的含量

注射用双黄连(冻干)样品经微波消解后,利用电感耦合等离子体质谱(ICP-MS)测定其中B、Al、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Cd、Ba、Hg等15种微量元素的含量。结果表明,方法回收率为81.6%～96.3%,检出限为0.001～1.53 ng/g,方法快捷、准确、灵敏度高,可以用于注射用双黄连(冻干)的微量元素的测定,同时也进一步完善了注射用双黄连(冻干)无机元素分析,为其质量控制提供了参考依据。     

三螺杆挤出机螺杆元件混合特性的数值研究

采用聚合物流体分析软件Polyflow对倒三角形三螺杆挤出机的6种螺杆元件的流道模型进行了三维等温数值模拟。使用Fieldview软件对结果进行统计处理,并采用不同的评价指标来表征混合性能,进而比较螺杆元件之间的混合特性。结果表明,捏合块的剪切和拉伸作用均强于螺纹元件;中性捏合块和左旋元件的回流效果好于其他元件;SME元件剪切弱于螺纹元件,但其拉伸作用和回流效果强于螺纹元件。因此,可根据物料对剪切的敏感性来合理地选择螺杆元件,以获得所期望的产品性能。     

ICP-AES法测定有机硅触体中铅的含量

采用电感耦合等离子体发射光谱测定了甲基氯硅烷生产使用的触体中铅(Pb)的含量,研究了触体中存在的主要元素铜对Pb测定的光谱干扰。选择灵敏度较高的220.353 nm为分析谱线,采用与试样Cu含量基本匹配的测试方法。被测元素样品加标回收率为103%,RSD(n=10)小于3%。     

煤、煤泥和煤矸石燃烧过程锂镓稀土元素的迁移规律

掌握煤中伴生有价微量元素在燃烧过程的迁移规律,对伴生元素的利用意义重大。选取4种高铝煤炭、1种煤泥和2种煤矸石等不同组成特性的样品为研究对象,采用逐级化学提取方法分析了锂（Li）、镓（Ga）和稀土（REE）在原料中的赋存形态,考察了以上元素在300~1100℃燃烧过程逸出情况和在燃烧灰中的富集行为,探讨了元素迁移规律与原料组成特性的关联。结果表明,Li、Ga和REE在7种样品中的赋存形态均以硅酸盐态为主,在燃烧过程的逸出率有与原料灰分呈负相关、与挥发分和含碳量呈正相关的趋势。以上元素在灰中均发生了不同程度的富集,REE的富集倍数高于Li和Ga。原料中微量元素含量和挥发分越高、灰分越低,同等燃烧条件下所得灰中微量元素的含量就越高。     

Distribution of some trace elements in the H-Coal process development unit

To understand better the distribution and fate of some trace elements in coal liquefaction plant operated in a continuous mode, a study of six typical trace elements—Cd, Pb, Cr, Cu, Mn and Ni—was initiated at the HRI-operated H-Coal Process Development Unit at Trenton, NJ. Sampling was carried out carefully and the analytical effort was designed to prevent sample contamination and produce precise analyses. The results show that the trace elements studied enter the plant and remain associated with the denser, less volatile materials. Under equilibrium conditions there does not appear to be a buildup in the PDU of those trace elements studied.     

ICP-AES法测定基板玻璃中铂、铑等微量元素的研究

基板玻璃是显示器面板的关键玻璃材料,决定了面板的性能和质量,因此需要对其成分进行精确测定。基板玻璃生产过程中,用于澄清作用的铂金通道会受到侵蚀溶解出铂、铑。研究了基板玻璃中铂、铑等微量元素的测试方法,提出了基板玻璃的溶解制备方法,以氢氟酸挥发基体中氧化硅并以硝酸作为介质排除基体效应;探索了微量元素铬、钴、锰、镍、锆、铂、铑的光谱特性,分析了共存元素谱线叠加干扰影响,选取了各待测微量元素无干扰的最佳谱线波长;采用ICPAES中标准曲线法测试基板玻璃中的微量元素,该方法测试结果精密度和准确度高,对于实际生产具有重要的指导意义。     

毕节地区煤中微量有害元素的初步分析

分析了煤中微量有害元素研究的目的、意义,叙述了国内外对每种微量元素研究的历史和现状,提出对毕节地区煤微量有害元素中研究的方法。     

黔西北纳雍枝铅锌矿床微量和稀土元素地球化学特征

纳雍枝铅锌矿床是黔西北地区迄今研究程度较高的大型矿床之一,为探讨成矿物质来源和矿床成因,应用ICP-MS方法对该矿床的主要矿物闪锌矿和白云石进行了微量、稀土元素分析,结果表明:闪锌矿微量元素相对地壳元素丰度,富集Ga、Cd、Sb,贫In;白云石和围岩的稀土元素都具有富集LREE和低异常δEu(δEu<1)的特征,且白云...     

Distribution of toxic elements in the products of the extraction of bitumens from coal and peat

The effect of bitumen extraction conditions on the behavior of a number of toxic trace elements (V, Cr, Ni, Cu, Zn, As, Sb, and Pb) in solid fossil fuel samples was studied. It was found that the capacity of fossil fuels to concentrate trace elements can be monitored and the type of compound can be determined based on the dimensionless quantities of carbophilicity and concentration factors of the trace elements in coal and peat. The types of compounds in fossil fuels were found and graphically represented for the test trace elements.