杭州市大气逆温特征及对空气污染物浓度的影响

利用2003-2009年杭州市逐日探空观测资料及杭州市环境监测站空气污染物浓度监测资料,对杭州市主城区低空温度层结特征及与3种主要空气污染物（SO₂、NO₂和PM₁₀）浓度之间的关系进行了统计分析。结果表明：杭州市主城区低空大气温度层结全年以弱稳定为主,一年四季皆有逆温层存在;冬半年逆温发生频率高于夏半年,逆温层厚度冬季较厚、夏季较薄,逆温强度秋季最强、夏季最弱。通过计算污染物浓度与逆温特性的相关关系,发现污染物浓度与逆温层底高呈负相关,与逆温频率、厚度、强度呈正相关,由此说明杭州市主城区低空大气逆温层结状况是影响该市空气污染程度的重要因素之一。     

2001-2002水文年环太湖河道的水量及污染物通量

根据2001-2002水文年115条环太湖河道的同步环境监测资料,对水量及污染物通量进行了估算.全年的入湖水量为80.11×108m3,出湖水量为96.67×108m3.入湖水量主要通过西部河网以及西苕溪、望虞河等河流汇入太湖,其中西部河网的入湖量占总入湖量的60%;出湖水量主要通过太浦河、东苕溪以及东部河网汇出太湖,其中太浦河的出湖量占47%.污染物通量的估算结果是,CODMn、TN及TP的入湖总通量分别为37571t/a、28658t/a及1029t/a,出湖总通量分别为35431t/a、14600t/a及668t/a.CODMn、TN及TP入湖通量通过西部河网进入太湖的比例占63%、49%及47%;CODMn、TN及TP出湖通量通过太浦河汇出太湖的比例占51%、45%及34%.通过与上世纪90年代以前相同年型的数据进行对比,除TP外,其它各种污染物的入湖量均明显增加,且污染物在湖泊中的滞留率也显著提高.由此说明,环太湖河道入湖污染负荷的增加是太湖水环境恶化的根本原因.     

Emission of fine organic aerosol from traditional charcoal broiling in China

The indoor PM_2.5 aerosol samples for charcoal broiling source under Chinese traditional charbroiling and the ambient fine aerosols samples (PM_2.5) were collected in Beijing to investigate the characteristics of the charcoal broiling source and its impact on the fine organic aerosols in the atmosphere. The concentrations of 20 species of the trace organic compounds, including polycyclic aromatic hydrocarbons (PAHs), fatty acids, levoglucosan, and cholesterol in PM_2.5 were identified and quantified by GC/MS. The total PAHs and fatty acids emitted from charcoal broiling to PM_2.5 were 8.97 and 87,000 ng mg⁻¹ respectively. The concentrations of the light molecular weight (LMW) 3- and 4-ring PAHs were much higher than those of the high molecular weight (HMW) 5- and 6-ring PAHs. Fatty acids were the most abundant species in source profile, accounting for over 90% of all identified organic compounds. More polyunsaturated fatty acid (linoleic acids) than the saturated fatty acid (stearic acids) emitted in the cooking. Charcoal broiling is a minor source of PAHs compared to the source of biomass burning. Comparing the ratios of levoglucosan/fatty acid and levoglucosan/cholesterol in the charcoal broiling samples to the ambient samples, it is evident that meat cooking is an important source of fatty acids, but a less important source of cholesterol. Cooking, as one of the source of fine organic particles, plus other anthropogenic sources would be related to the formation of the severe haze occurred and spread over the urban atmosphere in most of the cities of China in the past several years.     

海口市空气污染特征分析及预报检验

利用海南省二次开发的CAPPS2.0模式,对2006年1月1日~2007年1月1日海口市逐日PM10、SO2、NO2污染浓度监测资料进行输出分析,得出海口市空气污染的变化特征。结果表明,污染物SO2和NO2的预报效果较好,而PM10预报效果较差。因此采用多元线性回归分析方法建立污染物浓度与气象要素的预报方程,并对PM10进行优化和校正,从而提高预报准确率。     

Carbonaceous materials in size-segregated atmospheric aerosols from urban and coastal-rural areas at the Western European Coast

A high-volume cascade impactor, equipped with a PM10 inlet, was used to collect size-segregated aerosol samples during the summer of 2004 at two Portuguese locations: a coastal-rural area (Moitinhos) and an urban area (Oporto). Concentrations of airborne particulate matter (PM), total carbon (TC), organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC) were determined for the following particle size ranges: < 0.49, 0.49–0.95, 0.95–3.0, and 3.0–10 µm. The total PM mass concentrations at the urban and coastal-rural sites ranged from 22.8 to 79.6 μg m^− 3 and 19.9 to 28.2 μg m^− 3, respectively, and more than 56% of the total aerosol mass was found in the fractions below 3.0 μm. At both locations the highest concentrations of OC and EC were found in the submicrometer size range. The regional variability for the OC and EC concentrations, with the highest concentrations being found in the urban area, was related to the contribution of local primary sources (mostly traffic emissions). It was also verified an enrichment of the small size particles in WSOC, representing on average 37.3(± 12.4)% and 59.7(± 18.0)% of OC in the very fine aerosol at the coastal-rural and urban areas, respectively. The amount of secondary OC calculated by the minimum OC/EC ratio method indicates that secondary organic aerosol formation was important throughout the study at both sites. The obtained results suggest that long-range transport and favourable summer conditions for photochemical oxidation are key factors determining secondary OC formation in the coastal-rural and urban areas. The ultraviolet absorption properties of the chromophoric constituents of the WSOC fractions were also different among the different particle size ranges and also between the two sampling locations, thus suggesting the strong impact of the diverse emission sources into the composition of the size-segregated organic aerosol.     

Case study of cloud physical and chemical processes in low clouds at Mt. Brocken

Frequency distributions of cloud base height and cloud type of low clouds observed between May and October 1998 at Mt. Brocken (Germany) have been derived from ceilometer measurements and synoptic observations. The summit at 1142 m a.s.l. was about 50% of that time in cloud. During daytime, Stratus clouds were the dominant cloud type (65%), whereas Cumulus clouds amounted to 27% and Stratocumulus clouds to 8%. Evidence was found that the increase of the cloud base height observed at Mt. Brocken continues since the end of the 1980s. An example for a clear anticorrelation between the liquid water content (LWC) of the cloud and the height above cloud base is shown. Other results of this detailed case study of a cloud event on October 8, 1998 concerning phase partitioning of water-soluble inorganic compounds, black carbon (BC) and organic carbon (OC) between the liquid and the interstitial phase will also be presented. The observed ion-specific increase in the solute mass per cubic meter of air with decrease of the distance between sampling position and cloud base was caused mainly by entrainment of air from the below-cloud layer. As expected, for sulfate, ammonia and nitrate, high scavenging coefficients (>0.8) were found. OC exhibits a high scavenging fraction of between 0.4 and 0.7; the value for black carbon (0.2–0.4) implies that soot was possibly to some extent internally mixed in the cloud condensation nuclei (CCN). Simultaneous measurements during a cloud event of HNO₂ and HNO₃ in the gas phase and N(III) and N(V) in the liquid phase were made for the first time.     

广西大厂锡多金属矿田100号矿体地质特征及成矿机理探讨

大厂１００号矿体赋存于龙头山生物礁灰岩中,是一世界罕见的特大型特富锡多金属矿体。对该矿体成矿地质背景,矿床地质牲及地球化学特征研究表明,龙头山生物礁具备优越的油气生、储、盖条件,为一古油藏,１００号矿体成 生物有机成矿作用有关。     

Distribution, isotopic variation and origin of sulfur in coals in the Wuda coalfield, Inner Mongolia, China

This paper describes coal petrographic characteristics, sulfur abundance, distribution and isotopic signature in coals in the Wuda coalfield, Inner Mongolia, northern China. Petrographic studies suggest that depositional environment influences petrographic composition. The No. 9 and No. 10 coal seams, which are thought to have formed on a tidal delta plain, have high collodetrinite contents (up to 66.1%) indicating enhanced gelification and bacteria activity during coal accumulation, and also have the highest sulfur content (3.46% and 3.42%). Both organic and pyritic sulfur isotope values (−12.3‰ to 5.8‰ and −18.7‰ to 1.1‰, respectively) are variable and generally tend to be more negative in high-sulfur coals than those in low-sulfur coals in the Wuda coalfield. The negative sulfur isotope values indicate that a large portion of sulfur in the high-sulfur coals has a bacterial origin. Sulfur isotopic compositions and variations within the section were used to propose a model to explain the origin of sulfur in these coals. The presence of pyritized rod-like bacteria, cyanophyte's gelatinous sheaths and degraded algae organic matter suggests that bacteria, and perhaps algae, may play an important role in the formation of these high-sulfur coals.     

关于沥青成因的讨论

以英国北威尔士和我国黔东湘西、新疆乌尔禾和塔里木的沥青为例,讨论了沥青的 Pb、Sr、Nd 同位素地球化学特征。结果表明:(1)沥青(前身物石油)的形成可能有多种途径,如壳源有机物生成(北威尔士、黔东湘西)和深源无机合成,后者的地质环境为地幔俯冲带(乌尔禾沥青)或下地壳麻粒岩相(塔里木);(2)沥青生成的时代比习惯认为的要古老得多。Pb、Sr、Nd 同位素还可给出原油运移、沥青沉淀的年龄。深入研究沥青的成因,对油气资源评价、勘探目标选择有重要意义。     

沉积盆地热化学硫酸盐还原作用评述

川东天然气藏H2S 气体泄露而导致重大伤亡事故后,热化学硫酸盐还原作用（TSR）成为了国内研究的热点。在油气储层条件下,尽管甲烷是最稳定的烃类,但TSR被诱发后,因为甲烷浓度远高于其它烃类,水溶甲烷能与硫酸根离子反应产生H2S 气体。同时,发现在参与TSR反应的有机质、起始温度、硫同位素分馏效应等方面,实验模拟结果均与地质实例观察结果有较大的差异,可能与TSR反应的催化剂等方面认识不足有关。并认为,TSR成因的H2S或元素硫可以在晚成岩期合并入有机质中,形成新的有机含硫化合物。但在自然界中,这类化合物很少被鉴别出来。