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1.
以催化裂解富气吸收液为测定对象,建立吸收液中目标离子(包括NO2^-,NO3^-,SO4^2-)的离子色潜分析方法。在选定色谱柱的前提下,通过优化淋洗液浓度等色谱条件,实现了在大量干扰离子S^2-及与SO4^2-相邻的未知离子存在的三乙醇胺溶液中目标离子的定量。方法的检出限分别为NO2^- 62μg/L,NO3^- 26μg/L,SO4^2- 90μg/L,RSD值为0.73%~1.19%,加标回收率在91%~109%。  相似文献   

2.
对离子色谱法测定饮用水中的F-,C1-,NO3- -N,SO4^2--4种阴离子的分析方法进行了优化。用正交试验法选择最优实验条件为:流速0.9mL/min,柱温32℃。4种阴离子检出限:F-0.02mg/L,Cl-0.04mg/L,NO3--N0.04mg/L,SO4^2- 0.16mg/L。测定结果相对标准偏差均小于5%,回收率为91.3%~106.1%,相关系数大于0.999。该方法操作简便,灵敏度、准确度高,标准工作曲线线性良好,可用于饮用水中F-,C1-,NO3^- —N,SO4^2—4种离子的同时分析。  相似文献   

3.
离子交换色谱法检测离子液体中阴离子   总被引:3,自引:0,他引:3  
建立了用阴离子交换分离柱、化学抑制模式、电导检测测定系列离子液体中BF4^-阴离子及其他杂阴离子(F^-、Cl^-、Br^-)含量的方法,并用于在线监控离子液体合成工艺中阴离子杂质含量。确定淋洗液组成为1.6mmol/L Na2CO3+3.9mmol/L NaHCO3,流速为0.6mL/min。本方法对所测阴离子检出限分别为50μg/L(F^-、Br^-)和80μg/L(BF4^-);线性范围在3个数量级以上;r〉0.999;回收率在98%~102%之间。方法用于对离子液体小试工艺样品分析及过程监控时,结果满意,样品的RSD小于2.6%(n=6)。  相似文献   

4.
整体柱离子对色谱对铬(Ⅵ)的快速测定   总被引:1,自引:1,他引:0  
研究了基于硅胶整体柱的离子对色谱快速测定Cr(Ⅵ)的方法,讨论了淋洗液浓度、乙腈浓度、流速、温度和pH等因素对分离的影响。用1.0mmol/L四丁基氢氧化铵-0.8mmol/L邻苯二甲酸(pH6.0)作为淋洗液,流速6.0mL/min,可以在1min内快速分离测定Cl^-、NO3^-、Cr(Ⅵ)、SO4^2-离子。Cr(Ⅵ)的检出限为1.02mg/L,保留时间和峰面积的相对标准偏差(RSD)(n=5)分别为0.2%和0.3%。将方法应用于测定地下水中的Cr(Ⅵ),回收率为104%。  相似文献   

5.
建立了以AS11—HC型阴离子交换柱分离、NaOH溶液为淋洗液、甲醇为有机改进剂、化学抑制电导检测测定啤酒中的F^-、C1^-、SO4^2-、NO3^-和PO4^3-?A的离子色谱方法。各被测离子的线性关系良好,相关系数为0.9778~0.9991.测定结果的相对标准偏差为0.02%~3.60%,样品回收率为97.88%~103.80%。  相似文献   

6.
高效液相色谱法同时测定水产品中10种生物胺的研究   总被引:7,自引:0,他引:7  
高效液相色谱法同时测定水产品中色胺、2-苯乙胺、腐胺、尸胺、组胺、章鱼胺、5-羟色胺、酪胺、亚精胺和精胺。样品经高氯酸溶液提取,丹酰氯衍生化,C18柱色谱分离,以0.1mol/L醋酸铵和乙腈作流动相梯度淋洗,254nm紫外检测。方法检出限(SIN=3):腐胺、亚精胺0.8μg/g;尸胺、组胺、酪胺、精胺1μg/g;章鱼胺、5-羟色胺2μg/g;2-苯乙胺3μg/g;色胺5μg/g。在0.2~10mg/L范围内,峰面积与质量浓度成良好的线性,相关系数r大于0.999。样品添加浓度在30、100和500μg/g的回收率为80%~111%,相对标准偏差为2.6%~15.8%。方法定量下限(LOQ)为30μg/g。本法简便、快速、灵敏、可靠。  相似文献   

7.
土壤中草甘膦的离子色谱法测定   总被引:19,自引:1,他引:19  
采用新型抑制器和电导检测,在流速为1.5mL/min的碳酸钠和碳酸氢钠的混合淋洗液中,分离含F^-、Cl^-、NO3^-、SO4^2-和草甘膦等物质,取得理想的分离效果和较高的灵敏度;F^-、Cl^-、NO3^-、SO4^2-和草甘膦检出限分别为0.26、0.41、0.41、1.15、17.4μg/L(S/N=3),具有良好的线性关系和重复性;对土壤样品进行测定,结果令人满意。  相似文献   

8.
应用气相色谱-质谱联用仪(GC-MS)建立了水果、蔬菜、粮谷等农产品中8种种衣剂农药残留的分析测定方法。样品用乙腈提取,通过石墨化碳或C18固相萃取小柱净化,经DB-5ms气相色谱柱分离,电子轰击电离(EI)、选择离子监测模式(SIM)对定量离子和定性离子进行MS测定。标准工作曲线范围0.02-0.5mg/L。样品中添加水平为0.005、0.010和0.020mg/kg时,回收率为74%~110%;相对标准偏差小于15%。检出限(S/N=3)为0.09~0.77μg/kg。  相似文献   

9.
建立了高效阴离子交换色谱脉冲安培检测器(HPAEC—PAD)测定碘离子的方法。以62.5mmol/LNaOH溶液作流动相,选用IonPac AS26型强亲水性阴离子交换分析柱,8min可以分离出碘离子,方法的检出限为0.05μg/L(25μL进样,3倍信噪比),标准曲线的线性范围为0.5—2000μg/L(r=0.9998)。1.0、2.5和25μg/L的碘离子标准溶液各9次进样的相对标准偏差分别为3.8%、2.6%和2.8%。试验了9种常见阴离子、3种易极化阴离子以及3种电化学活性物质对碘离子测定的影响,结果表明,在所选用的色谱条件下上述各化合物均不干扰碘离子的测定。用所建立的方法测定了盐水、矿泉水、海水、芹菜汁和紫菜浸提液等样品中碘离子含量,加标回收率在83%-114%。该方法具有灵敏度高、干扰小和样品前处理简单等优点。  相似文献   

10.
研究了用10mmol/L的NaOH溶液超声波提取,离子色谱法同时检测烟草中有机酸和阴离子的分析方法。采用美国Dionex公司DX-500型离子色谱仪,用H2O、5mmol/L NaOH和100mmol/L NaOH梯度淋洗,流速为1.5mL/min,成功地测定了烟草中的苹果酸、柠檬酸、NO3^-1、NO2^-、Cl^-、SO4^2-等成份。这些成分在检测条件下有良好的线性关系,相关系数r^2〉0.99,检出限为0.005~0.2mg/L,相对标准偏差为0.52%。9.14%,回收率为93.5%~107.7%;实验表明该方法具有分析时间短、线性范围宽、灵敏和准确、简单快速、试剂用量少等优点。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

16.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
19.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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