共查询到20条相似文献,搜索用时 93 毫秒
1.
2.
3.
本文介绍了一种燃烧氧化-缓释-非分散红外吸收测定生物降解材料中总有机碳含量的方法:先将试样用稀磷酸溶液酸化曝气去除碳酸盐后,在高温燃烧管中将试样中有机碳催化燃烧氧化为二氧化碳,二氧化碳被氢氧化钠溶液吸收稀释后,再通过滴定稀磷酸溶液将二氧化碳缓释,缓释的二氧化碳进入总有机碳分析仪中非色散红外检测器测定二氧化碳的质量。试验结果表明:该方法相对于燃烧氧化-非分散红外吸收法具有更高的精密度,另外与校准样的相对误差均小于2.0%,加标回收在96%~102%,具有抗干扰小、适用范围广、精密度高、正确度和稳健性好等特点,同时测定结果可溯源至相关的国家标准物质,对于测定生物降解材料总有机碳含量的测定具有一定的积极意义。 相似文献
4.
气相色谱法测定混合气体中一氧化碳、二氧化碳、甲烷含量 总被引:1,自引:1,他引:0
采用气相色谱法测定混合气体中一氧化碳、二氧化碳、甲烷含量,通过两个色谱柱来分离混合气体,得到相对保留时间,以外标法建立了三种气体的标准曲线,并通过精密度实验和准确度实验验证了检测方法的灵敏度、重现性,最终测定混合气体中一氧化碳、二氧化碳、甲烷摩尔分数分别为1.35×10~(-4),0.35×10~(-4),0.96×10~(-4)。 相似文献
5.
用作者建立的实验装置测定了二氧化碳-丙酮、二氧化碳-乙醚、二氧化碳-二氯甲烷三个二元体系露点压力下的饱和汽相体积和P,T,y数据,测定结果用修正的PR状态方程进行了关联。 相似文献
6.
7.
对管式炉燃烧-滴定法测定硅铁中碳硫进行了研究。采用氧化铜为助熔剂,在1350℃管式燃烧炉中通氧燃烧,产生的二氧化硫、二氧化碳分别用过氧化氢和乙醇-乙醇胺进行吸收,用氢氧化钠滴定硫,用乙醇-氢氧化钾溶液滴定碳。方法应用于硅铁标准物质碳硫的测定,三种硅铁标准物质碳含量测定结果的标准偏差RSD均不大于4%,硫含量测定结果的标准偏差RSD均不大于9%。证明该方法能快速,准确,简便的测定硅铁中碳硫含量。 相似文献
8.
利用气液双循环的高压气液平衡装置,测定了二氧化碳-环己烷在313.45K和323.3K以及二氧化碳-环己酮在313.25K和323.3K下的二元气液平衡数据。用作图检验法考察了实验数据的热力学一致性。马丁-侯(81)状态方程用于关联两个二元体系的气液平衡数据,计算值与实验值吻合良好。 相似文献
9.
10.
11.
12.
利用全自动碳氢分析仪采用库仑分析方法对煤中碳氢元素分析进行研究。论述了其工作原理,试验条件、试验方法,并对试验结果的精密度和准确度进行分析,从而得出可用该方法进行煤中碳氢元素分析的结论。 相似文献
13.
A laboratory apparatus that could be used to treat pure triglycerides under simulated deep fat frying conditions was designed
and built. By the use of this apparatus, the volatile decomposition products produced during frying could be quantitatively
collected at the same time. Pure trilinolein was treated in this apparatus at 185 C for 74 hr. The volatile decomposition
products were collected quantitatively. Their fractionation and identification will be reported in a subsequent paper. The
nonvolatile decomposition products were isolated from the treated trilinolein as the non-urea-adduct-forming methyl esters.
They constituted 26.3% of the treated trilinolein and were separated into seven fractions by repeated liquid column chromatography.
Chemical and physical analyses of these fractions indicated that the chemical reactions taking place under simulated deep
fat frying conditions were not entirely the same as those during simple heating under air. One of the seven fractions was
further purified by thin layer chromatography and then identified as a cyclic carbon to carbon linked dimer which amounted
to 4.9% of the treated trilinolein. Another fraction was further purified by thin layer chromatography, followed by gas chromatography,
and then identified as noncyclic hydroxy dimers formed through carbon to carbon linkages. The noncyclic dimers constituted
2.8% of the treated trilinolein. The other four fractions were depolymerized by hydroiodic acid. The depolymerization products
were fractionated by thin layer chromatography and then analyzed. It was estimated that the treated trilinolein contained
8.4% of trimers formed through carbon to carbon linkages, and 4.9% of dimers and trimers joined through carbon to carbon or
carbon to oxygen linkages in the same molecule and also trimers, in which all the three monomeric units were joined through
carbon to oxygen linkages.
Paper of the Journal Series, New Jersey Agricultural Experiment Station, Rutgers, The State University. 相似文献
14.
An apparatus for measuring the solubility of gas in liquid and that of liquid or solid in gas has been constructed. The apparatus can be used at system temperatures ranging from 20 to 70°C and at system pressures up to 15 MPa. The solubilities were determined by means of gravimetric measurements. The solubilities measured in this study for the carbon dioxide+n-decane and carbon dioxide + naphthalene systems agree very well with the literature values. The vapor-liquid equilibria of the carbon dioxide+Peace River bitumen system at 45 and 55 °C were studied. The new data indicate that the supercritical-fluid carbon dioxide can extract a fair amount of the light components from Peace River bitumen. 相似文献
15.
以活性炭(AC)为吸附增强材料,石蜡为相变材料,采用物理共混法制备了一种固-固相变材料。利用差示扫描量热仪、导热系数测定仪、高温综合热分析仪对所得相变材料进行了表征。结果表明,当活性炭质量百分含量不低于15%时,所得复合物宏观上表现为固-固相变;加入活性炭颗粒,可提高材料的导热系数和热稳定性。 相似文献
16.
17.
生产碳纤维的关键设备——碳化炉 总被引:1,自引:0,他引:1
具有耐热梯型结构的有机预氧丝经过高温热处理转化为含碳量在92%以上的无机碳纤维。实现这一转化的关键设备是碳化炉。工程实践与研究表明:其核心技术是宽口碳化炉及其配套的迷宫密封、废气排除和牵伸系统。对于ht级碳纤维生产线,炉口宽度需在1m以上,而且要正压操作,就需非接触式迷宫密封装置;为使热解废气不污染纤维,排除系统要畅通而瞬时排出;牵伸系统则是制造高性能碳纤维重要手段。 相似文献
18.
分别以白炭黑、碳纳米管、碳微球及石墨烯为增强剂,对天然橡胶复合材料的制备以及其力学性能进行研究。采用传统机械混炼法将复合材料进行混合,通过平板硫化机进行交联制备天然橡胶复合材料。分别考察不同增强剂的含量对橡胶复合材料力学性能的影响,找到最佳的添加量。分析了不同种增强剂对复合材料力学性能的影响规律,对其增强效果进行对比说明。采用电子万能拉伸测试仪、邵氏硬度计对复合材料的拉伸性能和硬度性能进行分析,结果表明:复合材料的力学性能随着炭微球、碳纳米管和石墨烯含量的增加而增加,随着白炭黑的含量的增加而减少,碳纳米管和石墨烯的增强效果较好。 相似文献
19.
Yrjö Viisanen Juha Hatakka Seppo Ahonen Markku Kulmala 《Aerosol science and technology》2013,47(1):224-229
By means of a simple optical apparatus the levels and variations of concentrations of elemental carbon in particles were measured. Additionally, relations between variations of elemental carbon, lead, sulfate, total suspended particle, and nitrate concentrations were studied. Calibration was performed on real samples analyzed by a wet chemical method. 相似文献
20.
二氧化碳与乙醇和异丙醇的二元汽液平衡 总被引:1,自引:1,他引:1
应用汽液双循环高压相平衡装置,测定了二氧化碳-乙醇和二氧化碳-异丙醇二元混合物分别在303.15K,310.15K和329.15K,压力范围为1.78~10.04MPa下的汽液相平衡数据。用DDLC-SRK方程关联两个二元体系的汽液相平衡数据,计算值与实验值吻合良好。 相似文献