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采用紫外吸收光谱法测定水样中SDBS的浓度,考察了水样中含苯类有机物PHP、其它同系物SDS和SLS、无机盐浓度等因子对测定结果的影响。实验结果表明:SDBS在紫外区222.5 nm处有一特征吸收峰,其吸光度值与水样中SDBS浓度呈线性正相关,可用于定量测定废水中SDBS的浓度;含苯类有机物PHP、同类物SDS和SLS和无机盐均对SDBS的吸光度测定值有一定的干扰和影响。其中PHP含苯类有机物对SDBS的紫外吸光度测定值影响最大,同类物SLS与SDS和无机盐对测定吸光度测定影响较小,且随着废水中SDBS浓度的增加或干扰物浓度的降低,其影响程度亦逐步减小;精密度和回收率实验结果表明,相对标准偏差为0.18%~0.3%,加标回收率93.6%~97.2%,方法快速、简便。可用于快速测定较为清洁水体中的微量SDBS和较高浓度SDBS废水的测定,但不适用于有机物及盐分含量高水样的测定。 相似文献
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通过实验分别测定了酸性镀铜光亮剂UBAC 1A和镀液中硫酸铜的吸收曲线。研究了光亮剂与吸光度之间的关系,确定了吸收曲线回归方程,获得了光亮剂UBAC 1A的吸光度标准曲线。讨论了不同硫酸含量对光亮剂和硫酸铜吸光度的影响以及不同含量的硫酸铜、干扰元素Fe2 和C l-分别对吸光度的影响。结果发现,当ρ(H2SO4)在20~160 g/L时,对光亮剂和硫酸铜的吸光度均无影响;镀液吸光度与硫酸铜含量呈线性关系;当ρ(Fe2 )<240 mg/L、ρ(C l-)<320 mg/L时,Fe2 和C l-对光亮剂的吸光度无影响。总结出了分光光度法测定酸性镀铜溶液中光亮剂UBAC 1A的体积浓度方法,取得了较好的应用效果。 相似文献
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分别选取红外光谱波数为1795 cm1处和1550 cm1处的吸光度值建立六氟丙烯和六氟环氧丙烷的压力-吸光度标准曲线,直接测定六氟丙烯和六氟环氧丙烷混合气体的红外光谱,用波数为1795 cm-1处和1550cm-1处的吸光度值分别计算得出六氟丙烯和六氟环氧丙烷的含量,进而计算得出六氟丙烯与六氟环氧丙烷的相对含量.该方... 相似文献
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分光光度法测定黄果柑中维生素C的含量 总被引:1,自引:0,他引:1
《四川化工》2019,(6)
研究黄果柑维生素C含量的测定方法。以维生素C标准品为对照品,采用固蓝盐B分光光度法于420nm波长处测定吸光度值,结果表明:维生素C标准浓度在0.0~20.0μg·mL~(-1)范围内与吸光度值呈良好的线性关系,线性方程为y=0.0557x-0.0083,R~2=0.9996;黄果柑中维生素C的平均含量为27.6mg·100g~(-1);精密度为S=0.515,RSD=1.87%;加标平均回收率为100.2%。固蓝盐B分光光度法操作简便、结果准确、回收率好,适用于黄果柑维生素C含量的测定。 相似文献
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水样中羧酸盐类聚合物含有的羧酸根离子与异染料尼罗蓝A溶液反应,造成尼罗蓝A在特定波长处吸光度下降,吸光度下降值与聚羧酸根离子浓度呈线性关系。据此原理,采用吸光度法测定循环冷却水中聚羧酸盐的浓度,讨论波长、尼罗蓝A用量、稳定时间等对吸光度的影响;同时,研究水中共存物质Ca~(2+)、Mg~(2+)、HEDP、HS01和BTA等对PAAS测定的干扰情况。确定最佳测试条件:缓冲溶液调节待测水样pH值至6.8,向待测样中加入适量EDTA溶液消除Ca~(2+)、Mg~(2+)干扰(EDTA:Ca~(2+)、Mg~(2+)物质的量之比略大于1∶1),取5.6×10~(-5)mol/L的尼罗蓝A溶液10 mL,在634 nm下稳定15 min,测定吸光度。 相似文献
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利用四氯乙烯对干法纺氨纶中残留溶剂进行萃取,采用液体池法进行红外光谱测试,选取特征吸收峰1690 cm-1或1665 cm-1为分析对象,用吸光度的相对峰高进行定量分析,建立了一种用傅里叶变换红外光谱快速定性、定量分析氨纶中溶剂(二甲基甲酰胺或二甲基乙酰胺)残存率的方法。由标准曲线可知:溶剂含量与红外光谱特征峰处吸光度的相对峰高有很好的线性关系,相关系数达0.999以上;样品定量检测的相对标准偏差约为0.4%,加标回收率约为97%;检测效率高,从制样到检测出结果仅需20 min左右。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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醋酸纤维素取代基分布与性质的关系 总被引:9,自引:0,他引:9
分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。 相似文献