气相色谱－质谱联用等技术鉴定四氯化碳生产中固体堵塞物

 本文采用气相色谱联用等技术，对ＣＣｌ＿４生产中的固体堵塞物进行了剖析。该固体堵塞物的主要成分和含量为：六氯苯，９８．６４％；其次还有１，１，２，３，４，４－六氯－１，３－丁二烯和１，２，３，４，５，５－六氯－１，３－环戊二烯。     

钾（Ⅰ）（4＇，5＇－二溴苯并－15－冠－5）配合物的研究

在丙酮介质中合成了４＇，５＇－二溴苯并－１５－冠－５分别与碘化钾和硫氰化钾的两种新型固体配合物。元素分析表明配合物的化学组成为Ｋ（Ｂｒ＿２Ｂ１５Ｃ５）Ｘ（Ｘ＝Ｉ￣－或ＮＣＳ￣－）。通过摩尔电导、红外光谱、Ｘ－射线粉末衍射分析对配合物进行了表证。从而证明，钾（Ⅰ）离子不仅容易与４＇，５＇－二溴苯并－１５－冠－５形成常见的１：２夹心式配合物，而ｎ还能生成稳定的１：１型固体配合物。     

1，2－亚丙基双（草酰胺根）桥联的线性三核铜（Ⅱ）配合物的合成与磁性

本文合成和表征了四种新的三核铜（Ⅱ）配合物｛［Ｃｕ（Ｌ）］２［Ｃｕ（ＣＨ３－ｅｂｏ）］｝（ＣｌＯ４）２（ＣＨ３ｅｂｏ表示１，２－亚丙基双（草酰胺根），Ｌ表示１，１０－菲咯啉（ｐｈｅｎ）（１），５－硝基－１，１０－菲咯琳（ＮＯ２－ｐｈｅｍ）（２），２，２’－联吡啶（ｂｐｙ）（３）和４，４’－二甲基－２，２’－联吡啶（Ｍｅ２ｐｙ）（４））．测定了四种配合物的变温磁化率（７７－３００Ｋ），求得交换参数分别为Ｊ１＝－２１９．６ｃｍ－１，Ｊ２＝－１９１．７ｃｍ－１，Ｊ３＝－２００．８ｃｍ－１，Ｊ４＝－１８５．５ｃｍ－１，表明Ｃｕ（Ⅱ）－Ｃｕ（Ⅱ）离子间存在着强的反铁磁交换相互作用．     

2－氯／2－甲磺酰基－5－（2－苯基－4－喹啉基）－1，3，4－噁二唑化合物的合成及其亲核取代的研究

借处理２－羟基－５－（２－苯基－４－喹啉基）－１，３，二唑同ＰＣｌ＿５／ＰＯＣｌ＿３之间的反应合成了２－氯－５－（２－苯基－４－喹啉基）－１，３，４－二唑（３）和通过２－基－５－（２－苯基－４－喹啉基）－１，３，４－二唑的甲基化，然后氧化制得２－甲磺酰基－５－（２－苯基－４－喹啉基）－１，３，４－二唑（６）．并分别研究了３和６同胺、叠氮及肼的反应，得到２，５－二取代的二唑新衍生物．初步观察了部分化合物的抗菌活性．     

3－硝基邻苯二甲酸根桥联双核钴（Ⅱ）配合物的合成、磁性及抗癌活性

合成了两种以３－硝基邻苯二甲酸根为桥联配体的新型双核钴（Ⅱ）的配合物，即［Ｃｏ２（３ＰＴ）（Ｐｈｅｎ）４］·（ＣｌＯ４）２·４Ｈ２Ｏ（配合物１）和［Ｃｏ２（３ＰＴ）（ＮＰｈｅｎ）４］（ＣｌＯ４）２·５Ｈ２Ｏ（配合物２）（３ＰＴ＝３－硝基邻苯二甲酸根，Ｐｈｅｎ＝１，１０－菲口罗啉，ＮＰｈｅｎ＝５－硝基－１，１０－菲口罗啉）。使用元素分析，ＩＲ，ＵＶ－ｖｉｓ和电导测定方法对该两配合物进行了表征。测定了配合物的变温磁化率，并对所得数据进行了理论分析，求得了配合物１、２的磁交换积分均为２Ｊ＝－９．２ｃｍ－１。对配合物进行了体外抗人白血病癌细胞实验。发现该两配合物均具有较强的抑制人白血病癌细胞的活性。     

对称三唑Schiff碱与铜的配合物合成及性能

合成了４种新型对称三唑水杨醛Ｓｃｈｉｆ碱的铜配合物［ＣｕＬ１Ｃｌ２］（Ⅰ）和三核配合物［Ｃｕ３（Ｌ２－Ｌ４）２Ｃｌ４］·ｎＨ２Ｏ（Ⅱ～Ⅳ），其中Ｌ１，Ｌ２，Ｌ３和Ｌ４分别为４－氨基－１，２，４－三唑、４－氨基－３，５－二甲基－１，２，４－三唑、４－氨基－３，５－二乙基－１，２，４－三唑和４－氨基－３，５－二羟甲基－１，２，４－三唑的水杨醛Ｓｃｈｉｆｆ碱．经元素分析、电导、红外光谱、热重分析、电子光谱、ＥＳＲ和变温磁化率表征，该类配合物为畸变四方构型．配合物Ⅱ的变温磁化率表明，铜离子间存在弱的反铁磁相互作用，Ｊ＝－１８．９ｃｍ－１，ｇ＝２．０８，Ｆ＝２．７×１０－３．配合物对Ｂ细胞增殖有抑制作用．     

3-吡唑基-6-取代均三唑并[3,4-b]-1,3,4-噻二唑的合成及生物活性

以１－甲基－３－乙基（－４－氯）－５－吡唑甲酰肼作原料，经两步得到４－氨基－３－（１－甲基－３－乙基（－４－氯）－５－吡唑基）－１，２，４－三唑－５－硫酮（３），３再与取代羧酸反应，得到一系列３－（１－甲基－３－乙基（－４－氯）－５－吡唑基）－６－取代均三唑并［３，４－ｂ］－１，３，４－噻二唑（４、５、６）．元素分析、１ＨＮＭＲ、ＩＲ和ＭＳ确定了它们的结构．初步生测结果表明：３具有植物生长调节活性，４ｂ、４ｄ、６具有杀菌活性．     

钾（Ⅰ）（4＇－溴苯并－15－冠－5）配合物的研究

合成了两种新型的固体配合物，其组成为Ｋ（ＢｒＢ１５Ｃ５）Ｘ（Ｘ＝ＮＣＳ￣－或Ｐｉｃ￣－）．钾（Ⅰ）离子不仅能与４’－溴苯并－１５－冠－５形成常见的１：２夹心式配合物，而且还能生成稳定的１：１型（Ｍ：Ｌ）固体配合物．     

2，4－二羟基－3－芳氨基甲基苯乙酮和8－乙酰基－3－芳基－3，4－二氢－5－羟基－2H－1，3－苯并■嗪的合成及其相互转化

研究了在氯化氢－乙醇溶液或乙醇溶液中，２，４－二羟基苯乙酮与甲醛和芳胺的Ｍａｎｎｉｃｈ反应，分别得到了５个２，４－二羟基－３－芳氨基甲基苯乙酮和５个８－乙酰基－３－芳基－３，４－二氢－５－羟基－２Ｈ－１，３－苯并嗪新化合物。用元素分析、ＩＲ、１ＨＮＭＲ、ＭＳ、ＵＶ确定了它们的结构，并成功地实现了２，４－二羟基－３－芳氨基甲基苯乙酮和８－乙酰基－３－芳基－３，４．二氢－５－羟基－２Ｈ－１，３－苯并嗪二类化合物的转化。     

2-溴代对苯二甲酸根桥联双核钴(Ⅱ)配合物的合成、磁性及抗癌活性

合成了三种以２－溴代对苯二甲酸根为桥联配体的新型双核钴（Ⅱ）的配合物，即［Ｃｏ２（ＢＴＰ）（ｐｈｅｎ）４］（ＣｌＯ４）２·Ｈ２Ｏ（配合物１）、［Ｃｏ２（ＢＴＰ）（Ｎｐｈｅｎ）４］（ＣｌＯ４）２·２Ｈ２Ｏ（配合物２）和［Ｃｏ２（ＢＴＰ）（Ｂｐｙ）４］（ＣｌＯ４）２·２Ｈ２Ｏ（配合物３）（ＢＴＰ＝２－溴代对苯二甲酸根，ｐｈｅｎ＝１，１０－菲罗啉，Ｎｐｈｅｎ＝５－硝基－１，１０－菲罗啉，Ｂｐｙ＝２，２′－联吡啶）。使用元素分析、ＩＲ、ＵＶ－Ｖｉｓ光谱和电导测定方法对该配合物进行了表征。测定了配合物的变温磁化率，并对所得数据进行了理论分析，求得了配合物１、配合物２和配合物３的自旋磁交换积分分别为：２Ｊ＝－６．５ｃｍ－１，２Ｊ＝－７．８ｃｍ－１和２Ｊ＝－８．９ｃｍ－１。对该三配合物进行了体外抗人白血病癌细胞的实验。发现该三配合物均具有一定的抑制癌细胞的活性     

On-line liquid chromatography-electrospray ionization mass spectrometry for determination of the brevetoxin profile in natural “red tide” algae blooms

Reversed-phase liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) was employed to analyze brevetoxin compounds associated with naturally occurring red tide blooms collected from Sarasota Bay, FL, USA. The LC-ESI-MS method utilizes a C₁₈ microbore column with a mobile phase consisting of methanol-water (85:15, v/v), a flow-rate of 8 μl/min and a post-column split ratio of 3:1 (UV-absorbance detector-mass spectrometer). Three known brevetoxins Btx-2, Btx-1 and Btx-3 were detected at 60 μg/l, 10 μg/l and 5.7 μg/l levels, respectively, in the natrual red tide bloom samples. This distribution differed quantitatively from that found in red tide culture extract samples. Btx-9 was not detected either in natural red tide bloom extracts or in red tide culture extracts, possibly due to the instability of this compound. An unknown component with a molecular mass of 941 found in the natural bloom extract was postulated to have the structure of a reduced form (hydrogenation of two double bonds in the alkyl side chain) of Btx-5.     

Integrated system for on-line gas and liquid chromatography with a single mass spectrometric detector for the automated analysis of environmental samples

An integrated system has been developed which combines liquid (LC) and gas (GC) chromatographic separation with a single mass spectrometer (MS). On-line solid-phase extraction (SPE) of 10–200 ml aqueous samples on a short (10 × 2.0 mm I.D.) precolumn packed with a styrene-divinylbenzene copolymer is used for analyte enrichment. The trace-enrichment procedure was automated by means of a PROSPEKT cartridge-exchange/solvent-selection/valve-switching unit. After sample loading, the precolumn is eluted on-line in two subsequent runs, first onto the GC-MS system and, next, onto the LC-MS system using a particle beam (PB) interface. Prior to entering the PB-MS, the LC eluent passes through the flow cell of a UV diode-array detector (DAD). Both GC-MS and LC-PB-MS generate classical electron ionisation (EI) and chemical ionisation (CI) spectra which are useful for the identification of low- and sub-μg/l concentrations of environmental pollutants covering a wide polarity and volatility range. The LC-DAD data provide additional means for quantitation and yield complementary spectral information. All three detection systems (GC-MS, LC-DAD, LC-PB-MS) and the trace-enrichment procedure are fully automated and controlled from the keyboard of the central computer. With such a ‘MULTIANALYSIS’ system GC-MS, LC-DAD and LC-MS data of the same sample can be obtained within 3 h. The system was optimised with nine chlorinated pesticides in drinking water as test mixture. With 100-ml samples detection limits in GC-MS were 0.0005−0.03 μg/l, and in LC-PB-MS 0.5–7 μg/l, both in the full-scan (EI) mode. Negative chemical ionisation (NCI) with methane as reagent gas improved the sensitivity of six halogenated compounds 3- to 30-fold and provided relevant information for structural elucidation of unknown compounds in real-world samples. LC-DAD detection limits varied from 0.01 to 0.05 μg/l. Relative standard deviations (R.S.D.) of retention times were less than 0.2% in all systems, R.S.D.s of peak areas were 5–15% for GC-MS and LC-PB-MS and less than 5% for LC-DAD. The ‘MULTIANALYSIS’ system was used to analyse surface water samples and river sediment extracts; several pollutants were detected and identified.     

Direct analysis of reference biofluids by coupled in situ electrodeposition-electrothermal atomic absorption spectrometry

The application of coupled in situ electrodeposition-electrothermal atomic absorption spectrometry (ED-ETAAS) to the determination of Pb in biological standard reference materials is described. In situ electrodeposition at a cell voltage of 3.0 V from 25-μl samples onto electrodeposited Pd is used to quantitatively separate the analyte from blood and urine matrices. With subsequent withdrawal of spent electrolyte, this overcomes the atomisation problems inherent with high salt and organic contents. ED-ETAAS is applied with minimal sample pre-treatment (acidification). The electrolysis process aids decomposition of the organic matrix, and the release of trace elements. Evolution of H₂ at the cathode counters fouling of the Pd modifier surface. The palladium deposit is renewed in situ for each determination. For AMI certified lyophilised blood, diluted 1+3 with 0.1 M HCl (18.1 μg/l Pb), the R.S.D. was 3.0% (peak height; n=5) and the detection limit (3 σ_blank; n=5) was 1.5 μg/l. Results for certified blood samples were AMI 72.3±4.3 μg/l (certified 76.2±7.6 μg/l) and Seronorm 34.2±2.0 μg/l (36±4 μg/l). The result for NIST SRM 2670 normal urine acidified to 1% HNO₃ was 8.1±0.6 μg/l (recommended value 10 μg/l).     

Analytical methodologies for determining the occurrence of endocrine disrupting chemicals in sewage treatment plants and natural waters

In this study, a method for assessing the occurrence of trace amounts of 12 representative estrogenic compounds in sewage and surface waters was developed. The selected substances were the phytoestrogens daidzein, genistein and biochanin A, the alkylphenols bisphenol A and 4-nonylphenol, the natural hormones 17β-estradiol, estrone, estriol and the synthetic hormone 17α-ethynylestradiol and the mycoestrogens zearalenone and two of its metabolites (α-zearalanol and β-zearalanol). The procedure consists in solid phase extraction (SPE) performed with OASIS cartridges followed by liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). Recoveries were all above 80% for each analyzed aqueous matrices. The developed method was applied to verify the occurrence of endocrine disrupters in environmental samples of sewage influents and effluents of an Italian STP. Phytoestrogens were present in effluents at concentrations ranging from 3 to 83 ng/l, whereas the levels detected for alkylphenols were in the range 13-36 ng/l for bisphenol A and up to 1 μg/l for nonylphenol. Estrogens and zeranols were determined at levels below 30 ng/l. Analysis of a river (Tiber) receiving effluent waters revealed high quantities of bisphenol A (15-29 ng/l) and nonylphenol (up to 1.2 μg/l), whereas the presence of all the other compounds were at levels of few ng/l.     

Speciation analysis of inorganic arsenic by microchip capillary electrophoresis coupled with hydride generation atomic fluorescence spectrometry

A novel method for speciation analysis of inorganic arsenic was developed by on-line hyphenating microchip capillary electrophoresis (chip-CE) with hydride generation atomic fluorescence spectrometry (HG-AFS). Baseline separation of As(III) and As(V) was achieved within 54 s by the chip-CE in a 90 mm long channel at 2500 V using a mixture of 25 mmol l(-1) H3BO3 and 0.4 mmol l(-1) CTAB (pH 8.9) as electrolyte buffer. The precisions (RSD, n=5) ranged from 1.9 to 1.4% for migration time, 2.1 to 2.7% for peak area, and 1.8 to 2.3% for peak height for the two arsenic species at 3.0 mg l(-1) (as As) level. The detection limits (3sigma) for As(III) and As(V) based on peak height measurement were 76 and 112 microg l(-1) (as As), respectively. The recoveries of the spikes (1 mg l(-1) (as As) of As(III) and As(V)) in four locally collected water samples ranged from 93.7 to 106%.     

A Semi-Automated Technique for the Separation and Determination of Barium and Strontium in Surface Waters by Ion Exchange Chromatography and Atomic Emission Spectrometry

Abstract

A semi-automated method for the separation and the analysis of barium and strontium in surface waters by atomic emission spectrometry is described. The method employs a semi-automated separation technique using ion exchange and an automated aspiration-analysis procedure. Forty specimens can be prepared in approximately 90 minutes and can be analyzed for barium and strontium content in 20 minutes. The detection limits and sensitivities provided by the described technique are 0. 00 3 mg/l and 0.01 mg/l respectively for barium and 0.00045 mg/l and 0.003 mg/l respectively for strontium.     

Silicon determination by inductively coupled plasma atomic emission spectrometry after generation of volatile silicon tetrafluoride

A method for the determination of silicon by inductively coupled plasma atomic emission spectrometry (ICP-AES) is described. The procedure is based on a discontinuous generation of volatile silicon tetrafluoride in concentrated sulphuric acid medium after injecting 125 μl of 0.1%, w/v sodium fluoride solution into 100 μl of the sample. The gaseous silicon tetrafluoride is fed directly into the ICP torch by a flow of 250 ml min⁻¹ Ar carrier gas. The calibration curve was linear up to at least 100 μg ml⁻¹ of Si(IV) and the absolute detection limit was 9.8 ng working with a solution volume of 100 μl. The relative standard deviation for six measurements of 10 μg ml⁻¹ of Si(IV) was 2.32%. The method was applied to the determination of silicon in water and iron ores.     

Investigation of Medium Power Radiofrequency Capacitively Coupled Plasmas and Their Application to Atomic Emission Spectrometry for the Determination of Aluminium in Water Samples

A medium power radiofrequency capacitively coupled plasma (275W, 27.12MHz) with low argon consumption (0.5Lmin^–1) was investigated to be used for the determination of aluminium in water samples pneumatically nebulised by atomic emission spectrometry. The plasma torch was operated in two geometric configurations, coaxial and coaxial-annular with single (SRTr.f.CCP) or double ring electrodes (DRTr.f.CCP), respectively. The optimum experimental parameters (observation height, Ar flow rate, distance between ring electrodes, matrix interference of Na⁺ and Ca²⁺ and anion nature) for Al 396.152nm emission were established. Under optimum operating conditions of the DRTr.f.CCP torch (6cm distance between annular electrodes), a detection limit of 70ngmL^–1 aluminium was found. Both operating parameters and several figures of merit of the investigated plasmas were compared to those of microwave plasmas and inductively coupled plasma used in atomic emission spectrometry. The method was used to control the quality of drinking and industrial water. Samples were mineralised with 2mL of 1+1 HNO₃ and 10mL of 1+1 HCl. In the range of 0.15–3.5mgL^–1 Al³⁺ the relative standard deviation varied between 3.7 and 8.6% (n=3). For two certified drinking water samples containing 0.206 and 0.218mgL^–1 Al³⁺ the recovery (n=5) was 97.6±6.8% and 98.6±7.3%, respectively.     

Interference-free atomic spectrometric method for the determination of trace amounts of germanium by utilizing the vaporization of germanium tetrachloride

Trace amounts of germanium can be determined by atomic spectrometry by utilizing the vaporization of germanium tetrachloride at ambient temperature. Using an intermittent or continuous flow reactor, the sample solution was mixed with concentrated hydrochloric acid to form volatile germanium tetrachloride which can subsequently be determined by atomic spectrometry. The conditions for the volatilization of germanium chloride were investigated in detail and rapid method for the determination of trace amounts of germanium in real samples was proposed. A detection limit of 0.5 ng ml⁻¹ (3σ_n−1) was obtained by using atomic fluorescence spectrometric detection and the precision found was 0.8% for a germanium concentration of l00 ng ml⁻¹. Atomic emission and absorption spectrometric methods were also tested. Owing to the high selectivity of the reaction, no interference was found in the determination. The method was applied to the determination of germanium in several standard and certified reference materials; the results obtained were in good agreement with the certified values.     

Metabolic Studies of Clostebol Acetate in Horses

Clostebol acetate (4-chlorotestosterone acetate) is a synthetic anabolic steroid which may be used to enhance performance in racehorses. Studies on the in vitro biotransformation of clostebol acetate with horse liver microsomes were carried out. Six metabolites (C1 – C6) were detected. They were 4-chlorotestosterone (C1), 4-chloroandrost-4-en-3-ol-17-one (C2), 4-chloroandrost-4-ene-3,17-diol (C3), 4-chloroandrost-4-ene-3,17-dione (C4), 4-chloroandrost-4-en-6-ol-3,17-dione (C5) and 6-hydroxy-4-chlorotestosterone (C6). Clostebol acetate (350 mg) was administered orally to 2 thoroughbred geldings. The parent drug was not detected in post-administration urine, and only three metabolites C1, C3, and 4-chloroandrostane-3,17-diol (C7) were observed. The metabolic pathway for clostebol acetate is postulated. These studies have shown that metabolites C3 and C7 could be used as potential screening targets for controlling the abuse or misuse of clostebol acetate in racehorses.