超高硫煤有机相中的元素硫与铁复合物的证据

运用高性能静态二次离子质谱从中国贵州（六枝）超高硫原煤有机相中观测到元素硫与铁的复合组成离子,由此,首次以确切的实验证据了过去关于煤中可能存在铁－硫复合结构的理论推测,同时本工作还表明,所采用的超高灵敏度和微区离子探针分析方法,适于今后进一步探讨硫及其它有害元素在煤中的复杂化学赋存状态。     

从高硫煤的抽提物和残渣中检测元素硫

利用化学抽提结合质谱分析方法对我国贵州贵定及四川松藻的高硫煤进行了分析测试实验证实我国西南贵定和松藻超高硫煤的原煤中存在元素硫。其中,以八个硫原子（Ｓ８）为且成的元素硫部分可抽提,而其余部分则被束缚于煤的有机相中,并须真空加热至２５０℃以上才释放出来,此结果表明,元素硫普遍存在于高硫煤中,另外,还讨论了煤中元素硫定量和有机硫定量相关的问题。     

高硫炼焦煤化学结构及硫赋存形态对硫热变迁的影响

利用红外、拉曼、热重及XANES等技术对不同煤阶高硫炼焦煤的化学结构、原煤及焦样形态硫分布进行了准确判定,对煤中化学结构及硫赋存形态与硫的热变迁行为进行了关联分析。结果表明,高硫炼焦煤中硫的热变迁行为不仅与硫赋存形态有关,而且受化学结构不同的高硫炼焦煤热解挥发分释放特性的影响。较低煤阶高硫炼焦煤中脂肪结构热分解产生大量挥发分,且挥发分释放温区较宽,形态硫分解产生的活性硫与挥发分中富氢组分相结合,形成更多的含硫气体转移到气相中,提高了热解脱硫率,焦炭体相中噻吩硫相对含量高于表面,硫化物硫则与之相反。煤化程度升高,煤中稳定噻吩类硫含量增多,挥发分释放量减少,热解脱硫率降低,且形态硫在焦炭体相与表面的分布差异不明显。无机硫脱除率与黄铁矿硫分解程度直接相关,热解过程中也将形成部分新的无机硫滞留于焦中。煤结构及有机硫的赋存形态决定了有机硫脱除率,煤阶升高时有机硫脱除率明显降低。     

硫的发展与应用

硫是一种非金属元素，属于氧族元素（ⅥA族）。硫的发现和使用具有悠久的历史，现代化学中含硫生命分子、含硫药物、含硫材料、精细化学品等都十分普遍。从硫元素的发展历史出发，逐步介绍硫化学在人类生活中的重要用途。重点介绍当代硫化学在生命功能、药物作用、食品和有机光电材料中的重要用途，尤其是生活中常见的含硫药物、含硫食品和含硫材料的主要成分以及它们独特性质的化学本源。     

C_（60）与某些有机小分子的气相离子－分子反应

Ｃ_（６０）与某些有机小分子的气相离子－分子反应中国科学院长春应化所刘淑莹教授等发现气相Ｃ６。在化学电离质谱中分别与３种氯代甲烷和４种氯代乙烷的分子离子及其碎片离子发生气相离子－分子反应，观察到Ｃ。０的几十种气相加合离子（其中大多数为含氯原子的）。通?..     

贵州省六枝、遵义矿区煤中汞和硫的赋存相关特性研究

选取贵州省六枝（LZ)、遵义（ZY）两不同矿区的高汞高硫煤为研究对象,对煤样进行煤浮沉、逐级化学萃取等实验,利用低温灰化（LTA）和X射线衍射（XRD）等手段,分析研究煤中汞和硫存在形式和两种元素之间的相关性。结果表明,在LZ煤中,硫主要以黄铁矿硫的形式存在,汞主要赋存于黄铁矿中,煤中硫和汞有很好的相关性;在ZY煤中,硫主要以有机硫的形式存在,汞主要赋存于黏土矿中,汞与硫不存在相关性。     

新峪焦精煤中硫在族组分间的赋存规律研究(英文)

为从煤的本体组成结构方面来阐述煤中硫的赋存与分布规律,以高含有机硫的新峪焦精煤为对象,采用萃取反萃取的煤全组分分离方法和XPS、GC/MS等分析技术,对原煤和各族组分中的不同形态无机硫和有机硫含量进行了研究,重点考察了有机硫在煤有机质本体中的赋存规律。结果表明,无机硫的分布主要依赖于其自身在煤主体中的粒径大小和密度高低,与煤族组分本身结构关联较小。无论是原煤还是族组分,其有机硫均以噻吩型硫占主导;共轭结构为主的分子外环境,使共轭结构类有机硫的电子结合能降低,而使脂肪结构类硫的电子结合能升高,反之亦然。有机硫在煤中分布总体均衡,不会因为族组分结构不同而产生较大差异;但有机硫的类型硫赋存比例则与族组分本身的结构特征有所关联,不过其差别相对较小。轻质族组分中只含有一种有机硫小分子化合物,且相对丰度较小。     

液/液界面萃取循环伏安法测定Pb2+离子研究

本文利用吡咯烷二硫代氨基甲酸铵（APDC）作为螯合剂,甲基异丁酮（MIBK）作为萃取剂,将水相中的Pb2+萃取到有机相中,利用经典的三电极系统研究该有机相在液/液界面的伏安特性。实验结果表明,该电化学过程是一个由扩散控制的不可逆过程,Pb2+的萃取物从有机相转移到水相。铅萃取物的转移峰在0.16V vs.SCE处,并且在1.0×10-5~ 9.0×10-5mol/L范围内与峰电流大小成正比。这一方法为工业废水中铅的在线、现场测定提供了可靠、灵敏的监测方法。     

有机分子笼的合成及应用

近年来,作为一类具有永久空腔结构的三维有机分子,有机分子笼引起了科研工作者的广泛关注,在超分子化学中（主要是主客体相互作用）扮演着重要角色。早期研究中通常采用不可逆法制备有机分子笼,往往存在反应步骤多、分离提纯复杂、合成难度大等问题。为了有效解决上述问题,研究人员将动态共价化学引入到有机分子笼的合成中,从而简单、高效地制备出一系列不同的有机分子笼。关于有机分子笼的应用研究也在不断拓展中。研究发现,有机分子笼不仅在分子识别、分子反应器等方面存在广阔的应用前景,而且其可以通过自组装形成多孔材料,在气体吸附、分离等领域展现了巨大的应用潜能。本文中,我们综述了有机分子笼在合成方法（主要基于动态共价化学反应）及应用研究方面的最新进展。     

有机化合物中硫元素微量测定方法的一些改良

作为有机元素微量定量分析方法系列报道之一,本文对目前普遍应用的氧瓶燃烧分解样品,钡盐法滴定有机硫的分析方法进行了规范化,探讨了溶液pH对测定的影响,检测了磷元素及氟元素对测定的干扰,并建立了适用于测定含磷有机化合物中硫元素的钡盐滴定法.针对钡盐法测定低含量硫元素时误差较大,本文建立了基于氯冉酸钡与硫酸根离子反应的分光光度法,该法准确可行,适用于测定低含量有机硫元素.     

金-硫团簇负离子组成特征的探讨

报导了金/硫靶在静态二次离子质谱实验条件下形成的组成通式为Au1－15S0－5的团簇负离子.其中,Aun组成系列具有典型的奇数优势,属于金的一元团簇负离子.其余组成系列（Au1－15S1－5）则属于金 硫二元团簇负离子.研究发现,金 硫团簇负离子具有以下与组成密切相关的特征: （1）它们继承了金一元团簇负离子的奇数优势;（2）它们中硫原子数仅限于5,而金原子数则在较大范围变化;（3）它们完全没有多数其它金属与非金属（包括硫）二元团簇正/负离子共有的MenNn型组成优势;（4）它们以上组成特征及其它细节恰似碳 磷这样的典型非金属二元团簇正/负离子.基于这样的组成特征可提出,金 硫团簇负离子在构成上包含着相对完整的金一元团簇组件,在形成机制上源于金一元团簇与硫一元团簇（或称为:限于五原子的多硫单元）之间的再团簇化.关于再团簇化机制中的相互作用问题,即两类团簇间是依靠末端原子交叉成键还是依赖两类团簇中异种原子之间静电诱导力等“非共价键”作用的问题,则有待于今后研究证实.     

Precise and fast secondary ion mass spectrometry depth profiling of polymer materials with large Ar cluster ion beams

We demonstrate depth profiling of polymer materials by using large argon (Ar) cluster ion beams. In general, depth profiling with secondary ion mass spectrometry (SIMS) presents serious problems in organic materials, because the primary keV atomic ion beams often damage them and the molecular ion yields decrease with increasing incident ion fluence. Recently, we have found reduced damage of organic materials during sputtering with large gas cluster ions, and reported on the unique secondary ion emission of organic materials. Secondary ions from the polymer films were measured with a linear type time‐of‐flight (TOF) technique; the films were also etched with large Ar cluster ion beams. The mean cluster size of the primary ion beams was Ar₇₀₀ and incident energy was 5.5 keV. Although the primary ion fluence exceeded the static SIMS limit, the molecular ion intensities from the polymer films remained constant, indicating that irradiation with large Ar cluster ion beams rarely leads to damage accumulation on the surface of the films, and this characteristic is excellently suitable for SIMS depth profiling of organic materials. Copyright © 2009 John Wiley & Sons, Ltd.     

Kinetics studies of aqueous phase reactions of Cl atoms and Cl2(-) radicals with organic sulfur compounds of atmospheric interest

A laser flash photolysis-long path UV-visible absorption technique has been employed to investigate the kinetics of aqueous phase reactions of chlorine atoms (Cl) and dichloride radicals (Cl2(-)) with four organic sulfur compounds of atmospheric interest, dimethyl sulfoxide (DMSO; CH3S(O)CH3), dimethyl sulfone (DMSO2; CH3(O)S(O)CH3), methanesulfinate (MSI; CH3S(O)O-), and methanesulfonate (MS; CH3(O)S(O)O-). Measured rate coefficients at T = 295 +/- 1 K (in units of M(-1) s(-1)) are as follows: Cl + DMSO, (6.3 +/- 0.6) x 10(9); Cl2(-) + DMSO, (1.6 +/- 0.8) x 10(7); Cl + DMSO2, (8.2 +/- 1.6) x 10(5); Cl2(-) + DMSO2, (8.2 +/- 5.5) x 10(3); Cl2(-) + MSI, (8.0 +/- 1.0) x 10(8); Cl + MS, (4.9 +/- 0.6) x 10(5); Cl2(-) + MS, (3.9 +/- 0.7) x 10(3). Reported uncertainties are estimates of accuracy at the 95% confidence level and the rate coefficients for MSI and MS reactions with Cl2(-) are corrected to the zero ionic strength limit. The absorption spectrum of the DMSO-Cl adduct is reported; peak absorbance is observed at 390 nm and the peak extinction coefficient is found to be 5760 M(-1) cm(-1) with a 2sigma uncertainty of +/-30%. Some implications of the new kinetics results for understanding the atmospheric sulfur cycle are discussed.     

Time‐of‐flight secondary ion mass spectrometry and gas chromatography–mass spectrometry studies of alkanethiol self‐assembled monolayers on nanoporous gold surfaces

The dimerization of alkanethiol mixtures (hexanethiol, octanethiol, and dodecanethiol) to form self‐assembled monolayers (SAMs) from headspace on nanoporous gold surfaces was studied for the first time using gas chromatography (GC/MS) and time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS). The nanoporous gold surfaces were obtained by an acidic etching of a 585‐gold alloy. Field emission scanning electron microscopy (FE‐SEM) was utilized to study the change of the surface geometry and porosity of the gold surfaces before and after etching. Alkanethiols were deposited from the vapor phase above the thiol solutions (headspace) on nanoporous gold plates and nanoporous gold solid‐phase vmicroextraction (SPME) fibers. The nanoporous gold substrates were analyzed by TOF‐SIMS and GC/MS, respectively. The TOF‐SIMS spectra exhibited various gold–sulfur ion clusters and specific peaks related to the adsorption of thiols such as deprotonated monomers, thiolate–Au, dimers (e.g., dialkyl sulfides–Au and dialkyl disulfides–Au). The GC/MS analysis of headspace extractions of alkanethiol mixtures by nanoporous gold SPME fibers showed a high extraction efficiency of alkanethiol, dialkyl sulfide, and dialkyl disulfide when compared with the commercial SPME fibers (DVB‐CAR‐PDMS and CAR‐PDMS). Different GC/MS optimization factors were studied including the extraction time and desorption temperature.     

Evaluation and comparison of layered titanate nanosheets using TOF‐SIMS and g‐ogram analysis

The evaluation of nanostructure is important to develop the highly controlled nanomaterials. In this study, two kinds of layered titanate nanosheets, which were produced by using hexylamine and laurylamine, respectively, as surfactants were investigated by Gentle Secondary Ion Mass Spectrometry Gentle‐SIMS (G‐SIMS) and g‐ogram, which is the latest Time‐of‐Flight Secondary Ion Mass Spectrometry (TOF‐SIMS) data analysis method for detecting more intact ions and obtaining the information on original chemical structures of samples precisely from complicated TOF‐SIMS spectra. As a result, molecular related ions of the surfactants were detected from each sample, and the structural information of samples was obtained. From both samples, surfactant molecular ions connected with hydrocarbon were detected as more intact ions rather than molecular ions of themselves. It was suggested that hydrophobic domains of their lamellar mesostructure are formed robustly by more than two surfactant molecules connected with each other linearly. After all, important information on the chemical structure of the layered titanate nanosheets, which would be difficult to be found by using typical structural analysis methods such as X‐ray diffraction and transmission electron microscopy, were obtained using G‐SIMS and g‐ogram. Therefore, it was shown that g‐ogram and G‐SIMS are helpful to evaluate the nanostructured materials. And it was also shown that g‐ogram is applicable to organic–inorganic materials which contain long hydrocarbon structures. Copyright © 2015 John Wiley & Sons, Ltd.     

Analysis of antioxidants in insulation cladding of copper wire: a comparison of different mass spectrometric techniques (ESI–IT,MALDI–RTOF and RTOF–SIMS)

Commercial copper wire and its polymer insulation cladding was investigated for the presence of three synthetic antioxidants (ADK STAB AO412S, Irganox 1010 and Irganox MD 1024) by three different mass spectrometric techniques including electrospray ionization–ion trap–mass spectrometry (ESI–IT–MS), matrix‐assisted laser desorption/ionization reflectron time‐of‐flight (TOF) mass spectrometry (MALDI–RTOF–MS) and reflectron TOF secondary ion mass spectrometry (RTOF–SIMS). The samples were analyzed either directly without any treatment (RTOF–SIMS) or after a simple liquid/liquid extraction step (ESI–IT–MS, MALDI–RTOF–MS and RTOF–SIMS). Direct analysis of the copper wire itself or of the insulation cladding by RTOF–SIMS allowed the detection of at least two of the three antioxidants but at rather low sensitivity as molecular radical cations and with fairly strong fragmentation (due to the highly energetic ion beam of the primary ion gun). ESI–IT‐ and MALDI–RTOF–MS‐generated abundant protonated and/or cationized molecules (ammoniated or sodiated) from the liquid/liquid extract. Only ESI–IT–MS allowed simultaneous detection of all three analytes in the extract of insulation claddings. The latter two so‐called ‘soft’ desorption/ionization techniques exhibited intense fragmentation only by applying low‐energy collision‐induced dissociation (CID) tandem MS on a multistage ion trap‐instrument and high‐energy CID on a tandem TOF‐instrument (TOF/RTOF), respectively. Strong differences in the fragmentation behavior of the three analytes could be observed between the different CID spectra obtained from either the IT‐instrument (collision energy in the very low eV range) or the TOF/RTOF‐instrument (collision energy 20 keV), but both delivered important structural information. Copyright © 2009 John Wiley & Sons, Ltd.     

Simultaneous determination of microgram amounts of chlorine or bromine or iodine and sulfur in organic compounds

A general method for the simultaneous and rapid determination of microgram amounts of chlorine or bromine or iodine and sulfur in organic compounds is described.The procedure is based on the combustion of the sample, containing approximately 0.005 meq of Cl or Br or I and 0.005 meq of S. by the Schöniger flask technique, using potassium hydroxide and hydrazine hydrate as absorption solution. The excess of hydrazine is eliminated with hydrogen peroxide after combustion.This method allows complete reduction of halogens to halides and oxidation of sulfur to sulfate.The halide ions are titrated with mercuric perchlorate and diphenylcarbazone as indicator; the sulfate ions with barium perchlorate and dimethylsulfonazo(III) as indicator.The results obtained are in good agreement with calculated values.     

Matrix‐enhanced secondary ion mass spectrometry: the influence of MALDI matrices on molecular ion yields of thin organic films

In this work the effect in secondary ion mass spectrometry (SIMS) of several frequently used matrix‐assisted laser desorption/ionisation (MALDI) matrices on the secondary ion intensities of low molecular weight (m/z 400–800) organic dyes and a pharmaceutical is tested. Matrix (10^?1 M) and analyte (10^?2 M) solutions were made in methanol. Mixtures with several concentration ratios were prepared from these solutions and spincoated on Si substrates prior to time‐of‐flight (TOF)‐SIMS analysis. In some cases the presence of the MALDI matrices caused a considerable increase in the positive secondary (protonated) molecular ion signals. Enhancements of a factor of 20 and more were recorded. Generally, of the matrices used, 2,5‐dihydroxybenzoic acid and 2,4,6‐trihydroxyacetophenone brought about the highest intensity increases. It was also shown that matrix‐enhanced (ME‐)SIMS is capable of lowering the detection limits for molecule ions. However, the enhancement effect is strongly influenced by the analyte/matrix combination and its concentration ratio. As a result, finding an optimal analyte/matrix mixture can be a very time‐consuming process. Mostly, the presence of the matrices causes changes in the relative ion intensities in the TOF‐S‐SIMS spectra. Compared to the spectra recorded from samples without matrices, only a few additional peaks, such as signals that originate directly from the applied matrix or adduct ions, are observed in the mass spectra. Sometimes molecule ions and some characteristic fragments at high m/z values, that cannot be recorded without matrix, do appear in the spectrum when a matrix is present. In the negative mode no enhancement effect is observed on applying the studied MALDI matrices. The results obtained from samples treated with MALDI matrices are also compared to SIMS results for the same samples after Ag and Au metallisation (MetA‐SIMS). For three of the four tested compounds Au MetA‐SIMS resulted in higher ion yields than ME‐SIMS. For both techniques possible mechanisms that can account for the enhancement effect are proposed. Copyright © 2005 John Wiley & Sons, Ltd.     

Cluster TOF‐SIMS imaging of human skin remains: analysis of a South‐Andean mummy sample

A skin sample from a South‐Andean mummy dating back from the XI^th century was analyzed using time‐of‐flight secondary ion mass spectrometry imaging using cluster primary ion beams (cluster‐TOF‐SIMS). For the first time on a mummy, skin dermis and epidermis could be chemically differentiated using mass spectrometry imaging. Differences in amino‐acid composition between keratin and collagen, the two major proteins of skin tissue, could indeed be exploited. A surprising lipid composition of hypodermis was also revealed and seems to result from fatty acids damage by bacteria. Using cluster‐TOF‐SIMS imaging skills, traces of bio‐mineralization could be identified at the micrometer scale, especially formation of calcium phosphate at the skin surface. Mineral deposits at the surface were characterized using both scanning electron microscopy (SEM) in combination with energy‐dispersive X‐ray spectroscopy and mass spectrometry imaging. The stratigraphy of such a sample was revealed for the first time using this technique. More precise molecular maps were also recorded at higher spatial resolution, below 1 µm. This was achieved using a non‐bunched mode of the primary ion source, while keeping intact the mass resolution thanks to a delayed extraction of the secondary ions. Details from biological structure as can be seen on SEM images are observable on chemical maps at this sub‐micrometer scale. Thus, this work illustrates the interesting possibilities of chemical imaging by cluster‐TOF‐SIMS concerning ancient biological tissues. Copyright © 2012 John Wiley & Sons, Ltd.