In situ detection of melanomas by fluorescence measurements

Special thanks are due to Dr. H. Schmitt for cooperation and to W. Schmehl, H. Wickert, and P. Bernhardt for excellent technical assistance. This work was supported in part by grants from the Bundesministerium für Forschung und Technologie, from the Deutsche Forschungsgemeinschaft, from the Fonds der Chemischen Industrie, and from the Hoechst company.     

水体有机和无机颗粒组分变化对散射和后向散射特性影响研究

研究颗粒物的比例构成对散射及后向散射特性的影响,对推动水色遥感的发展具有重要的意义。本文结合2017年6月和9月秦皇岛附近海域的实测数据,获取了各站位有机颗粒（POM）、无机颗粒（PIM）的浓度以及散射、后向散射等光谱参数,并进行了相关性分析。结果表明,受水体颗粒物浓度的影响,各波段比后向散射系数的变化幅度明显增大,变异系数CV最大值出现在550 nm处;通过建立散射、后向散射系数与总悬浮颗粒物浓度（SPM）以及与PIM和POM之间的关系模型发现,水体的后向散射受水体颗粒物构成影响较大,与有机、无机颗粒物浓度之间的模型精度较高,均方根误差（RMSE）的变化范围为0.0094~0.0143,模型精度在700 nm处最好;同时,分析了无机颗粒物的比例构成（PIM/SPM）对散射效率和后向散射效率的影响,得出相对于散射效率Q_be,后向散射效率Q_bbe受无机颗粒物比例构成影响最大,但是Q_bbe与PIM/SPM的相关性并不是很高,决定系数R2为0.4。     

胶州湾夏季悬浮颗粒物组成特征研究

2005年8月采用FACSCalibur流式细胞仪等方法对胶州湾夏季悬浮颗粒物组成特征及影响因素进行了研究.结果表明,胶州湾夏季悬浮颗粒物浓度范围在12～17.4 mg/L,浓度从湾内到湾口有逐渐减少的趋势;悬浮体中有机颗粒物占总颗粒物数量的58.73%～72.1%,以小于1 μm的颗粒为主,1～2 μm,2～5 μm,大于5 μm的颗粒数量依次递减;活体颗粒含量达到40.05%～61.37%,并且活体颗粒的粒径也比较小,其粒径分布趋势与有机性颗粒分布趋势相似;有机颗粒、活体颗粒分布都具有近岸较高,离岸较低的特点;表层悬浮物有机颗粒、活体颗粒含量分别与温度、pH值和PO3-4-P之间具有较好的相关性.     

北极夏季大气气溶胶单颗粒研究

为研究北极地区大气气溶胶颗粒的物理化学特性,于2013年8月8~12日环Svalbard岛收集大气气溶胶样品,利用带能谱的透射电子显微镜(TEM-EDS)共分析2530个单颗粒,并获得颗粒物的形貌特征和化学组成.结果表明,北极地区颗粒物主要表现为5种类型,分别为海盐颗粒、富S颗粒、富Fe颗粒、含碳颗粒和矿物颗粒.后向气流轨迹显示,采样期间大气污染物主要来自于北极点周边的海洋上空和附近格陵兰岛地区.来自海洋上空的大气中主要包含海盐颗粒,所占数量比例为54.7%;经过陆地的大气样品中95.4%为矿物颗粒.利用时间密度因子法估算出北极地区PM2.5质量浓度范围为0.55~0.72mg/m3.     

气溶胶粒子在毛细管中沉积与再悬浮

采用亚微米单分散聚苯乙烯球形硬气溶胶粒子和脉冲进样技术,测定了气溶胶粒子在管道中的沉积率,研究了沉积率与流体速度、管道长度、管道直径和气溶胶粒子大小之间的关系.结果发现,在相同条件下,沉积率随管长增加而增大;随流体速度增加而减小.在相同体积流量下,沉积率与管径关系不大;而沉积率与气溶胶粒子大小之间的关系比较复杂.沉积的气溶胶粒子如果在更大流速冲击下,将发生反弹,部分气溶胶粒子从黏附表面上分离再次悬浮于流体中.     

Chemical composition of particles in the black sea atmosphere

Shipborne samples collected from the Black Sea atmosphere were analysed by instrumental neutron activation analysis, atomic absorption spectrometry and ion chromatography for approximately 40 elements and ions. Concentrations of most of the elements are found to be a factor of two higher in the western part of the Black Sea than corresponding concentrations in the eastern part. Main source regions for anthropogenic elements were in Europe. The WNW, WSW and SSW sectors together account for 70% of observed concentrations of elements. Principal component analysis showed a crustal, a marine and three anthropogenic factors. Two of the anthropogenic factors were the result of long-range transport of particles and the third indicated a local iron and steel industry. Atmospheric fluxes of elements to the Black Sea were calculated using observed concentrations, scavenging ratios and precipitation data and results were compared with riverine fluxes of elements. For crustal elements, riverine fluxes were found to be dominant, but for pollution-derived elements, atmospheric fluxes were comparable to riverine fluxes to the Black Sea.