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基于纵型微型炉裂解器的裂解气相色谱法(Py-GC)建立了涤/毛纤维混纺比例的测定方法。以石英砂为固体质量分散剂,将样品加入其中碾磨成粉末后称量进样,在550℃的裂解温度下得到相应的裂解色谱图,依据各自特征裂解谱图与释放气体分析曲线可识别涤纶与羊毛纤维;选择涤/毛二元混纺纤维裂解谱图上涤纶的特征裂解产物——联苯为定量峰,计算混纺纤维中涤纶的质量百分含量,进而推算出羊毛纤维的含量。样品和石英砂的最佳配比为0.02 g∶4 g,涤纶质量在0.0256~0.2048 mg范围内联苯的线性良好,相关系数R2=0.9952。对不同涤/毛混纺比例的实际样品进行了测定,相对标准偏差RSD<3%(n=3);本法与国标法所得结果的偏差小于5%。结果表明,本方法简便、准确,适合涤/毛二元混纺纤维混纺比例的质控分析。 相似文献
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设计了静电纺丝法制备多壁碳纳米管/聚乙烯醇复合纤维综合实验。该实验对纺丝浓度、纺丝电压、接收距离、接收面积、多壁碳纳米管的改性及其添加量对复合纤维形貌的影响进行研究,对纤维进行了红外光谱、扫描电镜测试分析,得到优化的静电纺丝制备多壁碳纳米管/聚乙烯醇复合纤维的电纺工艺。该实验易于分组操作,涉及高分子材料的改性、制备、形貌表征和结果分析等多方面内容,有利于学生巩固理论知识,提高实践能力和综合应用能力。 相似文献
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提出了电导率呈指数型分布的浓差极化层的介电模型. 利用传递方程研究了压力驱动膜过程的介电谱, 并导出层内电导率分布与宏观测量的电容和电导之间定量关系的理论表达式, 得到介电谱高低频特征值与浓差极化模数之间的关系. 计算结果表明, 较之线性分布电导率, 指数型分布电导率能更好地描述浓差极化层的介电谱. 研究表明, 介电谱及其特征值和弛豫强度随浓差极化模数和层厚度显著变化. 对由分离膜、主体溶液和浓差极化层组成的复合体系的介电谱进行了数值模拟, 发现电导较之电容其频率依存关系对浓差极化模数的变化更为敏感, 上述研究为利用介电谱在线监测膜分离过程提供了有价值的理论参考. 相似文献
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红外光谱示差分析早就有不少应用。但过去的示差分析方法是采用改变参比样品的浓度或厚度来获得示差光谱的,这只适用于溶液样品,同时还需要作补偿的标准样品,补偿又很难做到完全。故应用受到了限制。七十年代后期,红外分光光度计与计算技术联用得到了发展,使许多老的技术、方法有了新的突破。例如本文采用的计算机示差分析只要有二幅适于做示差处理的光谱(不一定需要补偿用的标准样品),便可反复进行计算处理,故容易做到补偿完全。这种谱信息的示差处理不同于化学分离,它虽得不到纯的化合物,却能得到纯化合物的光谱,且在一定程度上能解决化学分离不能解决的问题。这些都为示差技术应用提供了广阔的前景。本文介绍二个较成功的红外光谱计算机示差方法实例。 相似文献
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用傅里叶变换红外光谱差谱技术分析香烟添加剂 总被引:1,自引:0,他引:1
1引言用傅里叶变换红外光谱(FTIR)差谱技术研究分子变化报道较多,但应用于分析未知物组成尚未见报道。未知物组成复杂,为了使差谱运算简单化,本文采用微量加样涂膜法制样,在近8μm厚度下,保证了谱带尖锐和实验重复性,无需溶剂稀释样品;用普通可拆液体池代替固定液体池,可方便地拆洗;从直观的差谱屏幕上,仔细考察差谱过程中谱峰变化,进行谱带归属,以获得未知物结构组成的定性、定量红外信息。应用差谱技术分析香烟添加剂,可不需分离,快速给出定性、定量结果。2实验与结果2.1仪器与试剂FTS-40型FTIR光谱… 相似文献
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受前行化学反应和平行化学反应的示差脉冲极谱电流理论已有论述。本文报道了受扩散和后行化学反应(EC过程)控制的示差脉冲极谱电流方程式并用实验进行了验证,应用该理论求得的动力学参数与文献值一致。 相似文献
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钴卟啉功能化电纺纤维膜的制备及其苯胺检测应用研究 总被引:1,自引:0,他引:1
以四苯基钴卟啉为识别分子,可溶性聚酰亚胺为高分子载体,采用静电纺丝技术制备一种负载钴卟啉的聚酰亚胺电纺纤维膜,用于对微量苯胺蒸气的快速检测.结果表明,钴卟啉基团的引入并没有使纺丝条件和过程发生很大的改变,依旧可以得到直径均一、形貌良好的电纺纤维.制备的钴卟啉功能化聚酰亚胺电纺纤维膜卟啉单元负载量高、分布均匀,保持了钴卟啉的基本光谱特性.当置于苯胺蒸气中时,电纺纤维膜中的钴卟啉可与苯胺分子轴向配位,形成有效的能量转移复合物,引起电纺纤维膜的紫外光谱发生改变.并且随着苯胺蒸气浓度的增加,紫外光谱呈现规律性变化,从而达到对苯胺蒸气检测的目的.进一步由紫外光谱计算得到其检测限为7.82 mg/m3.经过5次连续的苯胺蒸气作用—氮气吹扫过程后,电纺纤维膜的紫外吸收光谱可基本回复至原有状态,显示了较好的重现性和优异的可重复使用性. 相似文献
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涤/棉纤维用丁烯二酸单酰胺染料的研究Ⅱ 总被引:1,自引:0,他引:1
为了简化涤/棉混纺织物印染上色的工艺流程,节约设备和能源,设计合成能同时上染涤/棉混纺纤维的单一染料,已成为目前国际染料界争相研究的热门课题。本文在前文的基础上设计合成了9种颜色以红和棕红为主的丁烯二酸单酰胺染料,以硝基苯胺为重氮组 相似文献
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青霉素G酶促裂解液的高效液相色谱分析 总被引:1,自引:1,他引:1
建立了用反相高效液相色谱测定青霉素G酶促裂解产物的方法。以与分离程度和分析时间有关的CRF为目标函数,用改进的单纯形法对流动相进行优化选择。结果表明本法快速、准确、简便。 相似文献
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通过对火场常见塑料载体与助燃剂混合燃烧残留物的分析,发展一种适用此类燃烧残留物的火灾物证鉴定方法,对火场中是否存在助燃剂进行判断,避免漏检情况的发生。应用热分析技术确定合适的闪蒸温度,在此温度下对塑料载体与助燃剂混合燃烧残留物进行闪蒸分析,并从实验条件选择、可行性分析、定性分析三方面对闪蒸技术进行评价。结果表明,闪蒸气相色谱-质谱(Flash GC-MS)技术可以检测到热塑性聚合物塑料载体与助燃剂混合燃烧残留物中残留的助燃剂特征组分,可对火场中是否存在过助燃剂进行辨别。闪蒸气相色谱-质谱技术丰富了现代火灾物证鉴定技术,能进一步辅助火灾物证鉴定工作,使鉴定结论更准确、可靠。 相似文献
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P. Junnila M. Latvala R. Matilainen J. Tummavuori 《Analytical and bioanalytical chemistry》1999,365(4):325-331
The method parameters of an almost one century old method for analyzing nickel as dimethylglyoximate were critically examined for the analysis of nickel raw materials and many of the method parameters were observed to have a significant effect on the Ni recovery. Thus, because the Ni precipitation method parameters vary a lot in analytical literature and also in practice, the obtained Ni results by different methods are not comparable. During this study it was found that the double precipitation worked out perfectly in eliminating the effects of impurity elements. The residual Ni content in the filtrates should also be measured to obtain accurate and precise Ni results. In complexing the impurity elements, tartaric acid, stabilized by acetic acid, turned out to be effective, and when added to the sample solution before ammonium addition, the best pH conditions for homogenous Ni precipitation with dimethylglyoxime were obtained. The optimized Ni determination method described was found to be accurate and highly reproducible when tested with Ni concentrates and standard reference materials containing high Ni concentrations. 相似文献
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SU5416 shows light-induced reversible geometric isomerism. A simple, reliable, isocratic HPLC method using an UV-vis detector at lambda(425nm) was developed. The method provides efficient (R(S)=3.5) analysis of the two isomers with retention of the isomeric integrity. Additionally, the method has linearity over a wide range (50-1000microg/mL, r(2)=0.99), is accurate (99-102%, RSD <4%), and reproducible (RSD <0.8%). The method was used for analyzing pharmaceutical samples and understanding the kinetics of SU5416 isomers in methanol. In addition, this method can be used for quantifying the non-isolatable E-isomer. 相似文献
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P. Junnila M. Latvala R. Matilainen J. Tummavuori 《Fresenius' Journal of Analytical Chemistry》1999,365(4):325-331
The method parameters of an almost one century old method for analyzing nickel as dimethylglyoximate were critically examined
for the analysis of nickel raw materials and many of the method parameters were observed to have a significant effect on the
Ni recovery. Thus, because the Ni precipitation method parameters vary a lot in analytical literature and also in practice,
the obtained Ni results by different methods are not comparable. During this study it was found that the double precipitation
worked out perfectly in eliminating the effects of impurity elements. The residual Ni content in the filtrates should also
be measured to obtain accurate and precise Ni results. In complexing the impurity elements, tartaric acid, stabilized by acetic
acid, turned out to be effective, and when added to the sample solution before ammonium addition, the best pH conditions for
homogenous Ni precipitation with dimethylglyoxime were obtained. The optimized Ni determination method described was found
to be accurate and highly reproducible when tested with Ni concentrates and standard reference materials containing high Ni
concentrations.
Received: 26 December 1998 / Revised: 12 April 1999 / Accepted: 14 April 1999 相似文献
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建立了测定粘胶型石膏绷带含量的方法。采用络合滴定法对半水石膏含量进行测定,考察了供试液制备方法,指示剂等因素。结果表明,络合滴定法能快速有效检测出半水石膏含量,滴定终点清晰,误差小,相对标准偏差RSD为1%,平均回收率为99.8%。所建立的检测方法操作简便,结果准确可靠,重现性好,能有效地控制粘胶型石膏绷带的质量。 相似文献
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Simultaneous correlation chromatography (SCC) is introduced as a technique capable of analyzing several different samples simultaneously on the same chromatographic column. The theoretical basis of the technique is outlined and a computer simulation demonstrates the feasibility of the method. The advantages and potential of the technique are discussed. The technique is applied experimentally in a calibration procedure for high-performance liquid chromatography. During the calibration, unknown sample and calibration standards are processed under the same conditions, resulting in very accurate calibration. Other applications are outlined. 相似文献