黄土沉积物原生组分磁化率与风力的物质分选

本研究选取我国西北地区典型荒漠表土和黄土-古土壤序列样品为研究对象,探讨黄土沉积物及其潜在物源区表土的原生磁性矿物浓度在不同粒级间的变化规律、黄土剖面中粒度与磁化率的关系,以验证中国黄土沉积物中磁性组分在搬运过程中是否存在分选作用及其变化规律。来自西北地区表土的地质证据表明,磁性组分主要集中于>63 μm和31~63 μm粒径组分,并以后者的含量最高;与之相对应,黄土沉积中原生磁性组分主要集中于31~63 μm粒径组分,但>63 μm粒径组分不再是主要载磁组分,其磁性显著低于31~63 μm粒径组分。同时,多个剖面的证据表明黄土沉积的原生磁化率与31~63 μm粒径组分的含量是同相位变化的,进一步支持沉积物中原生组分的磁化率受到风动力的分选作用影响。需要强调的是,沉积物原生磁化率的主要载磁粒径组分为31~63 μm的颗粒物,而并非最粗粒组分。本研究结果暗示,相较于沉积物的全样粒度,干旱半干旱地区风成沉积的磁化率在指示古风场强度方面具有潜力。

     

内蒙古典型草原和草甸草原相对花粉产量重估

相对花粉产量（RPP）是利用地层花粉数据定量重建古植被的重要参数,但目前估算的不同地区同一植物类型的RPP多存在差异。为了解植被盖度计算方法对花粉产量的影响,本项研究利用卫星影像数字化重新计算了内蒙古锡林郭勒典型草原和乌拉盖草甸草原采样点周边100 m以外的植被数据,利用ERV模型重新估算了主要花粉类型的RPP,并运用景观重建算法（LRA）进行了检验。锡林郭勒典型草原ERV模型分析显示,ERV子模型1结合1/d距离加权法与植被-花粉数据拟合度最高,得到的相关花粉源范围（RSAP）为1470 m;以蒿属为参照种（RPP=1±0）,各科属RPP依次为藜科（0.53±0.03）、十字花科（0.17±0.01）、唐松草属（0.14±0.02）、菊科（0.09±0.01）、莎草科（0.08±0.006）、委陵菜属（0.07±0.01）、禾本科（0.050±0.003）。乌拉盖草甸草原ERV模型分析显示,ERV子模型1结合Prentice距离加权法与植被-花粉数据拟合度最高,得到的RSAP为770 m;以蒿属为参照种（RPP=1±0）,各科属RPP依次为藜科（5.85±0.58）、蓼科（5.27±0.37）、石竹科（5.15±0.47）、莎草科（4.16±0.13）、菊科（1.63±0.09）、百合科（0.49±0.08）、唇形科（0.38±0.06）、禾本科（0.200±0.004）。重估的RSAP和RPP均与首次估算时存在差异,表明植被盖度计算方法确实会影响RSAP和RPP。景观重建算法对RPP检验结果表明,卫星影像数字化估算的RPP重建的植被盖度与实际植被的相关性更高。

     

埃达克岩研究的几个问题

在简略分析中国埃达克岩研究情况的基础上,讨论了新近在有关埃达克岩研究方面取得的主要进展,探讨了先前埃达克岩研究中很少或者没有注意到的特殊的地球动力学意义。强调O型埃达克岩的出现标志着大洋萎缩消减的开始,C型埃达克岩的出现则暗示地壳在此之前就已经加厚,同时认为要解决埃达克岩研究中存在的一些问题,在很大程度上还有赖于青藏高原的埃达克岩研究。     

四川九寨黄龙机场高填方地基变形三维动力分析

四川九寨黄龙机场具有高填方、高地震烈度、高海拔等三高的特点,高填方体地基在地震作用下的动力稳定与变形问题成为该机场需着重考虑的主要工程地质问题之一。在对目前各种动力分析方法研究的基础上,选用快速拉格郎日差分分析(FLAC)程序,对该机场元山子沟段高填方地基在地震作用下的变形规律进行了系统地研究,获得了一些有实际意义的认识。     

Shallow sediment deformation styles in north-western Campeche Knolls,Gulf of Mexico and their controls on the occurrence of hydrocarbon seepage

During German R/V Meteor M67/2 expedition to Campeche Knolls, southern Gulf of Mexico, a set of 2D high resolution seismic data was acquired to study the near-surface sediment structure and its relationship with hydrocarbon seepages in this salt province. The comprehensive survey covered 20 individual bathymetric highs or ridges and identified three principle structural types: Passive Type, Chaopopte Type, and Asymmetric Flap Type. The first type is the result of passive diapirism, whereas the latter two were initialized by a regional compressional event in the Miocene, but are later differently modified by salt tectonism. Chapopote Type structures appear as symmetrical domes, with uplifted coarse-grained Miocene sediments in their cores and rather thin syn-kinematic sediments covering the crests. Asymmetric Flap Type structures are also first folded as domes or ridges, but one flap later subsided together with salt evacuation, resulting in single uplifted monoclines. With the coarse-grained pre-kinematic sediments as reservoir units, both structural types can focus and accumulate hydrocarbons. The geometries of the structures suggest that hydrocarbons are accumulated in the center of the Chapopote Type structures and in the subsided flaps of the Asymmetric Flap Type structures. Hydrocarbon leakage from these thinly sealed reservoirs is regarded as the principle mechanism for the seepage in the study area, and accordingly the most seepage-prone positions are above these reservoirs. The seep locations suggested by analysis of sea-surface oil slick images of SAR satellite data are also examined in this study. These independently derived seep locations confirm the seepage-prone positions to be above the shallow buried reservoirs. This study suggest that the shallow sediment structures control the distribution of the hydrocarbon seeps of the north-western Campeche Knolls, although the hydrocarbons are sourced from the greater depth.     

黔西南州区域自动站气象资料绘图系统的研制

随着气象服务的不断推进,用户对气象服务产品的要求越来越高,提高气象服务产品的质量对于基层气象台站来说显得至关重要。目前,区域气象站的建设已覆盖到各乡镇,将这些区域气象站资料用直观的色斑图来显示,可有效提高气象服务质量和服务水平。系统综合使用VB、Fortran、Gr ADS等技术,实现对区域自动站气象资料的查询、处理与绘图等功能,并可分县制作绘图边界和色斑图,为决策气象服务提供精美素材。     

An approach to determination of phenolic compounds in seawater using SPME-GC-MS based on SWCNTs coating

Phenolic compounds have become one kind of the important pollutants of the marine environment. Single-walled Carbon nanotubes, as one-dimensional nano materials, have light weight and perfect hexagonal structure of connections, with many unusual mechanical, chemical and electrical properties. In recent years, with the research of carbon nanotubes and other nano materials, the application prospect is also constantly discussed. In this paper, homemade single-walled carbon nanotubes(SWCNTs) coating was used for establishing an analytical approach to the determination of five kinds of phenolic compounds in seawater using SPME-GC-MS. Optimal conditions: After saturation was conducted with Na Cl, and p H was adjusted to 2.0 with H_2SO_4, the extract was immersed in a water bath at 40 for GC℃-MS determination through 40-min agitating extraction at 500 rmin~(-1) and 3-min desorption at 280℃. The liniearities ranged between 0.01-100 μg L~(-1), and the determination limits ranged between 1.5-10 ngL~(-1). The relative standard deviation(RSD, n = 5) was less than 6.5%. For the phenolic compounds obtained from the spiked recovery test for actual seawater samples, the rates of recovery were 87.5%-101.7%, and the RSDs were less than 8.8%, which met the requirements of determination. Due to its simplicity, high efficiency and low consumption, this approach is suitable for the analysis of trace amounts of phenolic compounds in marine waters.     

Study on biogenic amines in various dry salted fish consumed in China

This study was carried out to investigate the biogenic amines（BAs）, physicochemical property and microorganisms in dry salted fish, a traditional aquatic food consumed in China. Forty three samples of dry salted fish were gathered from retail and wholesale markets and manufacturers, which had been produced in various regions in China. Cadaverine（CAD） and putrescine（PUT） were quantitatively the most common biogenic amines. About 14% of the samples exceeded the histamine content standards established by the FDA and/or EU. The highest histamine content was found in Silver pomfret（Pampus argenteus）(347.79 mg kg^-1). Five of forty three samples exceeded the acceptable content of TYR(100 mg kg^-1), and 23.26% of dried-salted fish contained high contents of biogenic amines(above 600 mg kg^-1). In addition, species, regions, pickling processes and drying methods made the physicochemical property, microorganisms and biogenic amines in dry salted fish to be different to some extents. The total plate count（TPC） was much higher than that of total halophilic bacteria in all samples. The biogenic amines, physicochemical property and microbiological counts exhibited large variations among samples. Furthermore, no significant correlation between biogenic amines and physicochemical property and TPC was observed. This study indicated that dry salted fish may still present healthy risk for BAs, depending on the processing methods, storage conditions among others.