ICP-MS及其联用技术在海洋地质研究中的应用前景

电感耦合等离子体质谱(ICP—MS)具有灵敏度高、检出限低、选择性好、线性范围宽、能进行多元素和同位素比测定等优点,广泛应用于环境、地质、医药、食品和高纯物质等领域。ICP—MS与其他进样及分析技术的联用,大大地扩展了其应用范围。重点介绍了ICP—MS与激光烧蚀(LA)、高效液相色谱(HPLC)及气相色谱(GC)的联用技术,探讨了它们在海洋地质研究中的应用前景。     

珠江口盆地Site4B柱状沉积物中脂肪醇分子化合物分布及其来源分析

本研究采用色谱质谱(GC-MS)和色谱-同位素质谱(GC-IRMS)方法,对珠江口盆地Site4B沉积物中脂肪醇分子化合物分布以及单体碳同位素组成进行了研究。结果表明:长链脂肪醇碳优势指数(CPIC26—34:9.41—24.56)、平均碳链长度(ACLC26—34:28.85—29.99)以及n C26—n C30脂肪醇平均碳同位素组成(?29.13‰±0.87‰、?32.98‰±1.28‰和?32.73‰±1.61‰)均揭示了n C26—n C34脂肪醇属于陆源高等植物来源,n C16—n C20和n C24脂肪醇较正的碳同位素组成反映了化合物的海洋细菌来源,而n C22脂肪醇偏负的碳同位素特征(平均?33.26‰±1.51‰)反映了化学自养细菌来源。Site4B沉积物中的陆源输入主要来自南海周边河流,从12.7ka BP至今的沉积时期(0—80cm,文中深度均为埋深)和末次冰盛期(102—120cm),其陆源输入主要来自台湾岛河流,而在19.3—12.7ka BP沉积时期(80—102cm)和更新世沉积时期(120—300cm),台湾岛、吕宋岛和珠江口河流的陆源贡献普遍较低。Site4B沉积物中的海洋生产力主要来自海洋微生物输入的贡献,并主要受到海水温差影响;其中在35—150cm层位,海洋输入和南海暖流的强弱带来的海水温度的高低有关,而在150—300cm层位,则主要和冰期-间冰期的冷暖气候带来的海水温差有关。     

冲绳海槽沉积物中陆源标志物——(艹屈)、苯并芘、苝、晕苯

近几年来,研究苯并芘、苝等多核芳烃(PAH)有机物在湖泊、海湾、海洋沉积物中的分布情况,引起了许多科学家的重视。众所周知,苯并芘是一类致癌物质,严重危害人们的健康。海洋沉积物中苝的存在,被许多有机地球化学家确认为有陆源物质输入的标志。作者研究了冲绳海槽沉积物中多核芳烃的分布情况,使用薄层色谱(TLC)分离技术,气相色谱(GC)、色谱—质谱—计算机(GC—MS—DS)鉴定,分析出PAH有(艹屈)、甲基(艹屈)、苯并     

文昌13—1／2油田原油地球化学特征研究

运用族组分、色谱、色谱-质谱等地化测试手段,总结了文昌13—1／2油田原油物性、母质类型及成熟度等地化特征,并分析了原油的来源。认为文昌13一1／2油田原油为典型的低硫、中高蜡陆相油源特征的正常成熟原油,推断原油主要来自文昌B凹陷文昌组滨浅湖相烃源岩。     

质谱成像技术在海洋生物中的应用进展

质谱成像是一种以质谱分析为基础的新兴分子影像技术,无须复杂的前处理过程即可对样品中多种被测分子的空间分布进行检测。目前,该技术已被广泛应用于医学、药学、微生物学、食品科学等诸多领域,其在海洋生物领域的应用也逐渐受到关注,为海洋科学基础研究提供了新机遇。本文在对不同质谱成像技术原理和特点进行简述的基础上,从海洋生物所产天然产物、关键代谢元素与体内污染物监测等方面,对近年来质谱成像技术在海洋生物中的研究应用进行了系统综述。     

长江口邻近陆架区沉积物来源的有机地球化学探讨

本文叙述了用碳同位素质谱、毛细管气相色谱和三维全扫描荧光法等现代分析方法测定的沉积物中有机质的分布特征,从有机地球化学的观点探讨了东海长江口邻近海域(30°06'—31°30'N,122°30'—124°30'E)有机沉积物的来源,结果表明,该区域沉积物中的有机质主要来自长江口陆源植物和近海洋浮游生物,且长江陆源物从河口向海迅速减少,其中大部分沉积在123°E以西附近,这与其他海洋地质学家的研究结果相符.     

南海第氏肉芝软珊瑚化学成分的研究 Ⅱ.Sarcophinone结构的测定

前文已经报道了从南海第氏肉芝软珊瑚(Sarcophyton decaryi)中分离到四种化合物的结构,本文报道化合物S_(303)的结构测定。 S_(303)为新化合物,定名为Sarcophinone,结构式如(Ⅰ)式所示。Sarcophinone为白色棒状结晶,熔点141—142℃,分子式C_(20)H_(28)O_3(高分辨质谱M~ 316.2025)。     

等离子体技术及其在地质上的应用

激光烧蚀微探针等离子体质谱的地质应用。自1989年以来，我们实验室就积极开展了激光烧蚀微探针(LAM)试样引入系统的研究工作，这种技术适合于ICP—MS分析地质样品中小体积矿物(激光烧蚀孔穴直径低于10—100μm)．对某些样品．采用Nd：YAG激光的基本IR波长(1064nm)，作为多数用途，4倍频率(uv)的波长(266nm)能产生较小的直径，并较好地形成孔穴．     

东太平洋海隆13°N附近沉积物中类脂化合物的分布特征及其对热液活动的指示

深海热液区的热液物质喷发扩散会对周围海底的沉积物产生影响,研究沉积物中类脂物有助于进一步了解热液活动对其产生的影响.对东太平洋海隆西翼13°N附近E271和E272站位沉积物中的正构烷烃和脂肪酸进行了气相色谱-质谱(GC-MS)分析.在两个站位的沉积物中检测到链长C11—C 35的正构烷烃,其以双峰型分布为主,其中短链...     

高分子量烃在海洋油气地球化学探测中的应用

高分子量烃主要包括饱和烃和不饱和烃两大类,是石油的主要组成部分。用于海底沉积物高分子量烃测量的主要方法有全萃取气相色谱、全扫描荧光和气相色谱/质谱或气相色谱/质谱/质谱等。全萃取气相色谱能够给出总萃取有机物、不溶复杂化合物、总链烃的量,指示热成因和新近有机物的贡献;全扫描荧光能够给出最大荧光强度、最大发射波长、最大激发波长、R值和指纹图形状等信息,不仅能够指示热成因烃和新近有机物的贡献,而且能够指示油气属性和含油气性;气相色谱/质谱或气相色谱/质谱/质谱测量海底沉积物中生物标志物组成特征,识别海底烃类渗漏的存在,给出渗漏烃源区源岩特征、热成熟度、成烃时代以及油质等信息。     

环境因子对菲在黄河口沉积物上吸附的影响

为研究多环芳烃从河口到近海的环境归趋行为与生态风险,考察了沉积物质量浓度、溶解性有机质、温度、盐度4种典型环境因子对菲在黄河口沉积物上吸附的影响,比较了黄河口与近海两种沉积物对菲的吸附性能。研究结果表明,沉积物质量浓度越低,单位质量颗粒物的菲吸附量越高;共存的溶解性有机质对菲的吸附具有增促作用,且腐殖酸比黄腐酸的作用更显著;温度的升高不利于菲的吸附,而盐度的增加有利于菲的吸附。菲在沉积物上的吸附是分配作用与表面吸附两种行为的耦合,其中黄河口沉积物以表面吸附为主,而近海沉积物以分配作用为主。近海沉积物菲吸附量显著高于黄河口沉积物菲吸附量。基于此,菲从河口到近海的迁移过程中,更易于在沉积物表面发生吸附沉降,从而可能降低水相中的生态危害,但对近海底栖生物具有潜在的健康生态风险。     

基于特征比值的原油中PAHs标志物风化规律研究

以渤海某原油作为研究对象进行综合模拟风化实验, 探讨了原油中五类PAHs组分的风化规律并筛选出其中稳定的诊断比值。结果表明: 经过50d风化, 原油中PAHs的分布已经发生了较大的改变, 其中萘系类损失最为严重, 菲系列所占的比例有所提高, 二苯并噻吩、屈、芴系列则保持相对稳定, 这为进一步筛选用于溢油来源鉴别的新诊断比值参数提供了一定依据; 经风化检验, 现有常用6种PAHs诊断比值在风化50d后较稳定, 可用于风化溢油的鉴别; 所选取新诊断比值中, 菲和屈系列、烷基取代二苯并噻吩类、烷基取代芴类抗风化能力较强, 共筛选出34种诊断比值可作为溢油鉴别的有效指标。     

渤海湾中部表层沉积物中多环芳烃分布及其来源

通过对渤海湾中部海域19个站位表层沉积物样品中检测出的13种优控多环芳烃(EPAs)进行同分异构体、甲基菲、GC—MS定量等分析,探讨了研究区沉积物中多环芳烃分布特征、输入来源和污染水平,结果表明,研究区表层沉积物中多环芳烃总含量为2.1~374.8ng/g,平均值为33.1ng/g,多环芳烃总含量呈现出由近岸区向深海区递减的趋势,除最高值BG-60站位外,研究区与其他地区相比污染水平为中—低;化合物组成上以3~4环为主,5~6环次之,从多环芳烃组成以及异构体和甲基菲比值分析表明,研究区沉积物中PAHs以燃烧来源为主,石油类产品和石油化工燃料燃烧贡献最大,煤、木材燃烧贡献次之;高含量的菲和4个高成熟度异常点证实石油烃PAHs污染客观存在。     

The influence of sediment resuspension on the degradation of phenanthrene in flow-through microcosms

The effect of sediment resuspension on the mineralization of phenanthrene was examined in microcosms and sediment slurries. In computer-controlled, flow-through microcosms, 14C-phenanthrene-amended sediments were resuspended into overlying oxic water at frequencies of 12, 4, 1, 0.25 and 0 d(-1). In slurry bottle experiments 14C-phenanthrene-amended sediments were continuously resuspended under oxic (excess air headspace) and anoxic (N2 headspace) conditions and mineralization was measured at periods from 2 h to 7 days. Our main findings were: (1) mineralization rate constants from the microcosms ranged from 0.001 to 0.01 d(-1) and increased with frequency of resuspension, (2) these rates fell between those measured in oxic and anoxic slurries and were predicted within a factor of 2.5 by a model in which mineralization depended on the degree of oxygen exposure, and (3) the phenanthrene-degrading bacterial community was more active in resuspended sediments incubated in the microcosms than in sediments which were not resuspended, or which were stored under refrigeration. We conclude from these experiments that the effects of sediment resuspension on phenanthrene degradation are consistent with a primary role of average oxygen exposure, and also an alteration in the PAH-degrading activity of microbial populations.     

PAH-biodegradation potential of indigenous microorganisms: evidence from the respiratory activity of surface sediments in the Quanzhou Bay in China

Seven stations were established in the Quanzhou Bay (24.73°-24.96°N, 118.50°-118.70°E) in China on three cruises to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) and the numbers of PAH-degrading bacteria in surface sediments. Assessing the biodegradation poten- tial of indigenous microorganisms by measuring the respiratory intensity with the addition of PAHs in sediment samples was also one of the aims of this study. The results show that the total PAH concentrations of the sedimen...     

The effect of biological and physical disturbances on the transport of arsenic from contaminated estuarine sediments

From the distribution of dissolved and solid arsenic species in a contaminated estuarine sediment and measured rates of flux of the various arsenic species we propose an empirical model for the cycling of arsenic between sediments and water column. The chemical form of arsenic in the sediment was largely determined by the redox state of the sediment. Arsenite was the dominant dissolved and solid species in the deeper reduced sediment, and arsenate was dominant in the oxidized surface layer. Arsenite in the interstitial water diffused toward the surface layer, where it was mostly oxidized to arsenate prior to leaving the sediments. Some arsenate adsorbed to the surface sediments and produced a surface layer enriched in arsenic. Small concentrations of methyl and dimethyl arsenic were produced in the sediments, and these also diffused into the overlying water.Nereis succinea, a burrowing polychaete, affected distribution and flux of arsenic from the sediments by its production of irrigated burrows. These burrows increased both the effective surface area of the sediment and the diffusion of arsenic by a factor of five. When the relative effects of the activities of Nereis succinea and physical resuspension are compared, results indicate that although physical resuspension can produce large pulses of materials from contaminated sediments, continuous biological activity is likely to be more important in the mobilization of contaminants from sediments in many estuarine environments.     

南大西洋沉积物中多环芳香化合物的组成特征研究

10 samples of sediments obtained from the South Mid-Atlantic Ridge were measured for the abundances and distributions of polycyclic aromatic compounds(PAHs). The total concentrations of PAHs(∑PAHs) ranged from 2.768 to 9.826 μg/g dry sediment. The ∑PAHs was higher in sample 22V-TVG10 and sample 26V-TVG05 which were close to hydrothermal fields, with the lowest value in sample 22V-TVG14 which was farthest from hydrothermal fields, suggesting a probable hydrothermal origin of ∑PAHs of samples. Approximately nine kinds of PAHs were identified, and low molecular mass tricyclic and tetracyclic aromatic compounds were predominant in the samples. The concentrations of fluoranthene which were typical as hydrothermal alteration compounds were the highest among PAHs with dry weight between 0.913–3.157 μg/g. The phenanthrene homologue was most abundant in the samples, and the ratios between parent phenanthrene and methylphenanthrene which probably reflected the degree of hydrothermal alteration ranged from 0.097 to 1.602. The sample 22V-TVG10 possessing a maximum ratio value showed the intense influence of the hydrothermal alteration on this sample, which might further imply that PAHs in sediments were mainly derived from the hydrothermal alteration.     

Hydrocarbons in Washington coastal sediments

The sources and distributions of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons are characterized in seventeen sediments from a highly river-influenced sedimentary environment off the southwestern coast of Washington. The major hydrocarbons are land-derived, introduced as preformed compounds and display long-term stability in sediment cores. A series of PAH of anthropogenic origin and two naturally derived compounds, retene and perylene, dominate the PAH composition in these sediments. Plantwax n-alkanes are the major aliphatic hydrocarbon constituents. Aliphatic hydrocarbons of marine origin, pristane and a series of four acyclic, multibranched C₂₅ polyolefins, are also observed in many sediments. The concentrations of these marine-derived hydrocarbons decrease to negligible levels rapidly with sediment depth from the sea-sediment interface, suggesting degradation.In general, the major land-derived hydrocarbons are concentrated in the midshelf silt deposit which extends northwestward along the continental shelf from the Columbia River mouth. A quantitatively more minor, natural series of phenanthrene homologs, also of terrestrial origin, is preferentially advected further offshore and deposited in continental slope sediments. These distributions are consistent with recognized particle associations for these compounds and sediment dispersal processes in this coastal environment. Sediment core records suggest the present pattern of dispersal has persisted for at least the past century and possibly since the Late Pleistocene.     

Responses of the mussel Mytilus edulis to copper and phenanthrene: Interactive effects

Most investigations of the responses of marine organisms to xenobiotics have concentrated on single contaminants and little is known of possible interactive effects of different classes of xenobiotics. As these latter seldom occur in environmental isolation, it is important to understand any interactions (synergistic or antagonistic) which may occur. This problem has been approached in the mussel Mytilus edulis by exposing estuarine mussels to copper (20 μg litre⁻¹) and phenanthrene (100 μg litre⁻¹) both individually and in combination, and measuring cytochemical subcellular and physiological responses after 3 days exposure and 3 days and 12 days recovery period. Results showed that mussels accumulated both xenobiotics during 3 days exposure. Depuration of copper was complete in 3 days recovery period, while loss of phenanthrene ranged from 30% to 70% of the concentration reached after 3 days exposure. There were no interactive effects on depuration.Both copper and phenanthrene reduced lysosomal hydrolase latency in digestive cells, and copper appeared to have a synergistic effect in preventing recovery of latency of lysosomal N-acetyl-β-hexosaminidase during the recovery period. There was evidence, in the digestive cells, of an antagonistic effect of copper on stimulation of activity of the microsomal respiratory chain (measured as NADPH-neotetrazolium reductase) by phenanthrene. Stimulation of this system by phenanthrene persisted after 12 days recovery period. There was a synergistic interaction of copper and phenanthrene on elevation of oxygen consumption and ammonium excretion. Clearance rates and scope for growth (physiological condition) were depressed by copper but not by phenanthrene after 3 days exposure.These findings are discussed in terms of known effects of copper and phenanthrene and the interactions are considered in terms of environmental effects measurements.     

皱纹盘鲍脂肪酸及脂肪醛二甲基缩醛的气相色谱/质谱分析

研究了用气相色谱/质谱法测定皱纹盘鲍中脂肪酸及脂肪醛二甲基缩醛的方法。皱纹盘鲍经Folch法提取总脂,用10%硫酸-甲醇溶液进行反应,通过气相色谱/质谱法对其脂肪酸及脂肪醛二甲基缩醛的组成进行分析。实验结果表明:10%硫酸-甲醇溶液能有效地对脂肪酸进行甲酯化衍生;同时促使烯醚键断裂,并与甲醇发生缩醛反应生成脂肪醛二甲基缩醛。通过气相色谱/质谱分析,从皱纹盘鲍中共鉴定出32个化合物,包括26种脂肪酸和6种脂肪醛二甲基缩醛;脂肪酸以C16:0、C20:4(n-6)、C20:5(n-3)、C18:1(n-7)和C22:5(n-3)为主;脂肪醛二甲基缩醛以C18:0DMA和C20:1DMA为主。皱纹盘鲍肌肉和内脏中的脂肪酸及脂肪醛二甲基缩醛的组成基本一致,但内脏中的4,8,12-三甲基十三烷酸含量远高于肌肉,具有极显著差异(P<0.01)。