石墨炉原子吸收法测定鱼中的铅

用硝酸和双氧水对鱼肉样品进行微波消解,然后用石墨炉原子吸收分光光度法测定鱼肉样品中铅的含量,测定结果的相对标准偏差为0．023％～0.137％（n=6）,加标回收率为83％～105％。     

微波消解-全谱直读等离子体发射光谱法测定面包改良剂中总溴的研究

采用微波消解样品、全谱直读等离子体发射光谱法(ICP—AES)测定面包改良剂中的溴含量。通过试验,优化了微波消解的条件和仪器的最佳工作参数：154．065nm波长处溴的检出限为0．015mg／L(3δ),线性范围为0．05～100mg／L,样品分析结果的相对标准偏差小于5％(n=7),加标回收率在93％～105％之间,样品分析结果与分光光度法相一致．该法简便、快速、灵敏、准确、线性范围宽。     

双波长分光光度法测定牛奶中的钙

采用双波长分光光度法测定牛奶中钙离子的含量。基于在碱性缓冲液中,钙与铬黑T（EBT）-聚乙二醇溶液作用形成1：1的配合物,利用等吸收双波长消去法,消除EBT自身的干扰。在558mn和645m处测定,得吸光度差△A,钙的质量浓度在0-4．8μg／mL范围内符合比耳定律,线性回归方程为△A=0．06964c＋0．00986,产0．9989。用干灰化法处理样品,通过测定样品的△4,查得样品中钙离子的含量。该方法测定结果的相对标准偏差为1．7％～7．6％（n=5）．平均加标回收率为79．0％～98．7％。     

离子色谱法测定水中总氮

用离子色谱法检测水中总氮,检测波长为205nm,整个分析过程仅需7min。方法的检出限为0．03mg／L．测定结果的相对标准偏差为2．1％～3．5％(n=7),加标回收率为99．0％～103．5％。用离子色谱法和分光光度法对水样进行测定,两种方法测定结果的相对偏差不大于2．1％。     

分光光度法测定汽油中的磷

提出了用磷钒钼酸分光光度法测定汽油中磷含量的方法，通过对汽油中可能存在的共存离子干扰进行了考察，确定了最佳测试条件。对合成标准样品分析，其相对误差小于±３．０％，相对标准偏差小于２．３％，对实际样品进行分析并进行了加标回收试验，磷回收率达到９８．８％～１０３．９％。是一种快速、可靠测定汽油中磷含量的方法。     

紫外法与红外法测定石油类的比对研究

将新近实施用于测定地表水中石油类的紫外分光光度法与红外分光光度法的方法特性参数以及应用于各类实际水样测定进行比对研究。结果表明,两种方法的实际检出限均为0.004mg/L、测定下限均为0.016mg/L,加标回收样品紫外法测定结果相对标准偏差为4.2%～6.6%,加标回收率为82.0%～96.0%;红外法相对标准偏差为3.8%～5.5%,加标回收率为82.0%～97.0%,精密度和准确度等性能指标相近,在使用不同萃取方式应用于各种不同来源和组成水体的实际样品测定时,同种方法所得结果相对偏差均小于10%,但紫外分光光度法所得结果与红外分光光度法最大相对偏差达到了49.0%,并且红外分光光度法测定结果较之紫外分光光度法与样品理论浓度值更为接近,表明紫外分光光度法对较复杂水体石油类样品的测定存在局限性。     

苯酚-硫酸分光光度法测定玉竹中多糖含量

采用苯酚-硫酸分光光度法测定湘玉竹中的多糖含量,检测波长为490 nm,方法的线性范围为0~0.12mg/mL,线性回归方程为A=0.397 6m 0.033 8,相关系数r=0.999 4。用该方法对湘玉竹样品测定,并进行加标回收试验,回收率为104.2%~106.9%,相对标准偏差为1.44%(n=5)。     

非完全消化-分光光度法测定环烷酸钴中钴

用非完全消化法处理环烷酸钴样品，即先用(1 3)HClO4-HNO3混合酸及H2O2消解破坏样品，使Co^2 游离出来，再用乳化剂Triton X-100溶解残存的环烷酸根而配制成透明的样品溶液。采用Co^2 -5-Br-PADAP-OP显色体系测定钴，在硫磷混合酸介质中共存元素与5-Br-PADAP形成的有色络合物被分解破坏，从而达到消除干扰的目的。建立了非完全消化-分光光度法测定环烷酸钴中钴的分析方法。对测定条件、线性范围进行了考察。测定结果与灰化法-分光光度法一致，相对标准偏差小于0．7％，加标回收率97．4％～103．0％。     

微波消解-分光光度法测定催化裂化原料中铁和镍

采用微波消解技术处理催化裂化原料，用分光光度法测定样品中的铁和镍。详细考察了微波消解消化剂的种类和用量，消解时间，消解压力和消解功率对消解效果的影响，确定了最佳微波消解程序。将微波消解技术与常规分光光度法结合测定催化裂化原料中的铁和镍，与常压溶样方法测定结果相吻合。该方法的相对误差小于0．9％，相对标准偏差(n=5)小于2．7％，两种样品制备方法的加标回收率均在95．2％～102．4％之间。实验结果表明：该方法简便、快速、准确、节省试剂、无环境污染，在催化裂化原料质量检测方面切实可行。     

油菜蜂花粉浸取液中黄酮含量的电导滴定测定

采用电导滴定法对芦丁标样及对花粉浸取液中黄酮进行了测定并与分光光度法进行比较,相对标准偏差小于5％,加标回收率94％～105％。     

Determination of phenol by flow-injection with chemiluminescence detection based on the hemin-catalysed luminol-hydrogen peroxide reaction

This study established a novel flow injection (FI) methodology for the determination of phenol in aqueous samples based on luminol chemiluminescence (CL) detection. The method was based on the inhibition that phenol caused on the hemin-catalysed chemiluminescence reaction between luminol and hydrogen peroxide in alkaline solution. Optimum conditions and possible mechanisms have been investigated. The linear range was 2.0×10(-9) to 4.0×10(-7)gmL(-1) for phenol. The proposed method is sensitive with a detection limit of 4.0×10(-10)gmL(-1). The relative standard deviation for 11 measurements was 2.3% for 1.0×10(-7)gmL(-1) phenol. The method was applied for the determination of phenol in waste water samples. The results obtained compared well with those by an official method.     

Rapid determination of products of phenol hydrogenation in a supercritical water system using headspace gas chromatography

This paper reports a headspace analysis technique for the determination of products, i.e., cyclohexanone (CE) and cyclohexanol (CL), of phenol hydrogenation in a supercritical water reaction system (SWRS) with water removal by hydrate formation. An addition of anhydrous calcium chloride leads to water absorption resulting in crystal water; thus, the samples can be quantitatively measured without the influence of water. After achieving equilibrium at 150°C and maintaining it for 5 min, the obtained results showed a relative standard deviation of less than 5.3% and the recovery ranged from 93% to 104%. The presented method is simple and accurate for the analysis of CL, CE and phenol in samples from phenol conversion in SWRS.     

Determination of phenol at ng l-1 level by flow-injection chemiluminescence combined with on-line solid-phase extraction

In this paper, a simple flow-injection chemiluminescence (CL) system combined with on-line solid-phase extraction is presented to determine phenol. This method is based on the enhancement effect of phenol on the luminol-K3Fe(CN)6 CL system. The solid-phase extraction promised the high sensitivity and improved selectivity of CL detection. With the calibration range from 4.7 ng l-1 to 470 ng l-1 phenol concentration, the proposed method was applied to analyzing phenol in water samples and the obtained results were validated by the standard method. The detection limit was determined as 0.66 ng l-1. The relative standard deviation was 1.5% for determining 4.7 ng l-1 phenol standard (n=7).     

连续流动分析法测定土壤中的挥发酚

建立了连续流动分析仪测定土壤中挥发酚含量的方法。称取5 g左右的土壤样品,以磷酸调节p H值为4,加入适量水并进行蒸馏,馏出液用连续流动分析仪测定挥发酚含量。在4.96~200μg/L范围内,挥发酚的质量浓度与相对峰高线性相关,线性方程为y=235.31x+51.6,相关系数r~2=0.999 8,挥发酚的检出限为1.24μg/L。取2种土壤样品分别进行6次平行测定,测定结果的相对标准偏差分别为1.52%,1.56%。对2种挥发酚标准样品进行测试,相对误差分别为1.90%,2.08%,加标回收率在87.8%~95.5%之间。该方法适合大批量样品的连续分析,且无需使用三氯甲烷,与传统方法相比更安全环保。     

Flow injection-chemiluminescence determination of phenol using potassium permanganate and formaldehyde system

It is found that phenol can react with potassium permanganate in the acidic medium and produce chemiluminescence, which is greatly enhanced by formaldehyde. The optimum conditions for this chemiluminescent reaction are in detail studied using a flow injection system. The experiments indicate that under optimum conditions, the chemiluminescence intensity is linearly related to the concentration of phenol in the range 5.0x10(-9) to 1.0x10(-6)gmL-1 with a detection limit (3sigma) of 3x10(-9)gmL-1. The relative standard deviation is 1.2% for 4.0x10(-7)gmL-1 phenol solution in 11 repeated measurements. This method has the advantages of simple operation, fast response and high sensitivity. The method is successfully applied to the determination of phenol in the waste water.     

高效液相色谱-串联质谱法同时测定废水中18种酚类污染物

建立了上清液直接进样-高效液相色谱-串联质谱同时测定废水中18种酚类污染物的分析方法。取5.0 mL水样置于具塞离心管中,加氨水调节pH≥12,摇匀,加入1.0 mL二氯甲烷-正己烷(2: 1, v/v)混合溶液并振摇5 min, 4000 r/min离心5 min,用玻璃针筒抽取上清液并经0.22 μ m聚四氟乙烯滤膜过滤,用甲酸调节水样pH至中性;然后采用Thermo Hypersil ODS柱(100 mm×2.1 mm, 5.0 μ m)分离,以甲醇-0.01 mol/L甲酸铵-甲酸水溶液(pH 4.0)为流动相进行梯度洗脱,流速0.2 mL/min,柱温30℃,进样10 μ L,电喷雾负离子电离(ESI^-)模式、多反应监测(MRM)模式进行检测,外标法定量。18种酚类化合物的峰面积与其质量浓度在一定浓度范围内均呈良好的线性关系(r²≥0.9991),方法检出限为0.10~0.88 μ g/L。测定低、中、高加标浓度的样品,18种酚类化合物的相对标准偏差为2.5%~9.9%(n=6);火工药剂废水与石油化工废水样品中的平均加标回收率为68.7%~118%(n=3)。此方法操作简单,灵敏度高,干扰小,分析速度快,可适用于环境废水中18种酚类污染物的同时分析。     

吸光度比值导数法同时测定苯酚,邻苯二酚和对苯二酚

研究了应用吸光度比值导测定苯酚，邻苯二酚对苯二酚３组分混合物。合成试样４次平行测定的相对标准偏差小于６％。回收率在９５％－１０４％之间。     

液-液萃取气相色谱法测定地表水中痕量苯酚

建立了液-液萃取气相色谱法测定地表水中痕量苯酚的方法。用盐酸调节水样至pH2左右,以二氯乙烷-乙酸乙酯(体积比为2∶1)混合溶液为萃取剂,以CD-5色谱柱进行分离,氢火焰离子化检测器检测苯酚的含量。苯酚的质量浓度在1.00~20.0μg/L范围内与其色谱峰面积呈良好的线性关系,线性相关系数r=0.999 3,检出限为0.03μg/L。样品加标回收率为93.0%~97.0%,测定结果的相对标准偏差小于2%(n=7)。该方法检出限低,精密度和准确度高,操作简便,适用于地表水中微量苯酚的分析。     

卷烟主流烟气中相关成分含量的快速检测方法

建立了一种快速测定卷烟主流烟气中相关成分的方法,其中包括一氧化碳、4-(甲基亚硝氨基)-3-吡啶-1-丁酮(NNK)、苯酚、巴豆醛、氨和氰化氢6种相关成分.采用在吸烟机上同时使用溶剂捕集和滤片捕集的方式,溶剂捕集氨、氰化氢和巴豆醛,滤片捕集NNK、氨、氰化氢和苯酚,样品采集后分别在高效液相色谱、离子色谱和液相色谱/质谱...     

Fast and sensitive high performance liquid chromatography analysis of cosmetic creams for hydroquinone, phenol and six preservatives

A fast and sensitive HPLC method for analysis of cosmetic creams for hydroquinone, phenol and six preservatives has been developed. The influence of sample preparation conditions and the composition of the mobile phase and elution mode were investigated to optimize the separation of the eight studied components. Final conditions were 60% methanol and 40% water (v/v) extraction of the cosmetic creams. A C18 column (100 mm × 2.1 mm) was used as the separation column and the mobile phase consisted of methanol and 0.05 mol/L ammonium formate in water (pH=3.0) with gradient elution. The results showed that complete separation of the eight studied components was achieved within 10 min, the linear ranges were 1.0-200 μg/mL for phenol, 0.1-150 μg/mL for sorbic acid, 2.0-200 μg/mL for benzoic acid, 0.5-200 μg/mL for hydroquinone, methyl paraben, ethyl paraben and propyl paraben, butyl paraben, and good linear correlation coefficient (≥0.9997) were obtained, the detection limit was in the range of 0.05-1.0 μg/mL, the average recovery was between 86.5% and 116.3%, and the relative standard deviation (RSD) was less than 5.0% (n=6). The method is easy, fast and sensitive, it can be employed to analyze component residues in cosmetic creams especially in a quality control setting.