<span style="font-family:Verdana;">A simple </span><span style="font-family:Verdana;">portable X-Ray Fluorescence (</span><span style="font-family:;" "=&qu...<span style="font-family:Verdana;">A simple </span><span style="font-family:Verdana;">portable X-Ray Fluorescence (</span><span style="font-family:;" "=""><span style="font-family:Verdana;">XRF) spectrometer was successfully used for </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;"> and nondestructive identification of the painting materials in two 15</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;"> century icons from the Onufri Museum in Beart, Albania. </span></span><span style="font-family:Verdana;">The spectrometer is based on a low power X-ray tube, a thermoelectrically cooled Si PIN detector and the spectrum acquisition system. It was assembled and adjusted at our laboratory for the investigation of the icons. </span><span style="font-family:Verdana;">A small number of pigments were clearly identified by </span><span style="font-family:Verdana;">X-Ray Fluorescence (</span><span style="font-family:Verdana;">XRF) measurements in both icons. This include</span><span style="font-family:Verdana;">s</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> Lead white for the white color, gold and yellow ochre for the yellow color, red lead, cinnabar and red ochre for the red color, as well as cooper based pigments for the green color. At the same time, the investigation raised some new questions that need further investigations by </span><span style="font-family:Verdana;">the use of additional analytical techniques. The results show that in both</span><span style="font-family:Verdana;"> icons are used similar pigments, which are in accordance with the Byzantine icon painting tradition.</span></span>展开更多
The Mandovi estuary is a prominent water body that runs along the west coast ofIndia. It forms an estuarine network with the adjacent Zuari estuary, connected via the Cumbharjua canal. The physico-chemical conditions ...The Mandovi estuary is a prominent water body that runs along the west coast ofIndia. It forms an estuarine network with the adjacent Zuari estuary, connected via the Cumbharjua canal. The physico-chemical conditions seen in the Mandovi estuary are influenced by two factors: the fresh water runoff during the monsoon season (June-September) and the tidal influx of coastal seawater during the summer (October to May) season. However, the effects of monsoon related changes on the phytoplankton of the Mandovi estuary are not yet fully understood. An attempt to understand the same has been made here by applying the process of daily sampling at a fixed station throughout the monsoon season. It was noticed that the onset of the monsoon is responsible for an increase in nitrate levels upto 26 μM from a (chl a) as high as 14 μg·L-1 during the same period. The phytoplankton population was observed through both chemotaxonomy and microscopy and was found to be composed mainly of diatoms. CHEMTAX analysis further uncovers the presence of several other groups of phytoplankton, the presence of which is yet to be reported in many other tropical estuaries. It includes chrysophytes, cyanobacteria, prasinophytes, prymnesiophytes and chlorophytes. The appearance of phytoplankton groups at various stages of the monsoon was recorded, and this data is discussed in relation to environmental changes in the Mandovi estuary during the monsoon season.展开更多
文摘<span style="font-family:Verdana;">A simple </span><span style="font-family:Verdana;">portable X-Ray Fluorescence (</span><span style="font-family:;" "=""><span style="font-family:Verdana;">XRF) spectrometer was successfully used for </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;"> and nondestructive identification of the painting materials in two 15</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;"> century icons from the Onufri Museum in Beart, Albania. </span></span><span style="font-family:Verdana;">The spectrometer is based on a low power X-ray tube, a thermoelectrically cooled Si PIN detector and the spectrum acquisition system. It was assembled and adjusted at our laboratory for the investigation of the icons. </span><span style="font-family:Verdana;">A small number of pigments were clearly identified by </span><span style="font-family:Verdana;">X-Ray Fluorescence (</span><span style="font-family:Verdana;">XRF) measurements in both icons. This include</span><span style="font-family:Verdana;">s</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> Lead white for the white color, gold and yellow ochre for the yellow color, red lead, cinnabar and red ochre for the red color, as well as cooper based pigments for the green color. At the same time, the investigation raised some new questions that need further investigations by </span><span style="font-family:Verdana;">the use of additional analytical techniques. The results show that in both</span><span style="font-family:Verdana;"> icons are used similar pigments, which are in accordance with the Byzantine icon painting tradition.</span></span>
文摘The Mandovi estuary is a prominent water body that runs along the west coast ofIndia. It forms an estuarine network with the adjacent Zuari estuary, connected via the Cumbharjua canal. The physico-chemical conditions seen in the Mandovi estuary are influenced by two factors: the fresh water runoff during the monsoon season (June-September) and the tidal influx of coastal seawater during the summer (October to May) season. However, the effects of monsoon related changes on the phytoplankton of the Mandovi estuary are not yet fully understood. An attempt to understand the same has been made here by applying the process of daily sampling at a fixed station throughout the monsoon season. It was noticed that the onset of the monsoon is responsible for an increase in nitrate levels upto 26 μM from a (chl a) as high as 14 μg·L-1 during the same period. The phytoplankton population was observed through both chemotaxonomy and microscopy and was found to be composed mainly of diatoms. CHEMTAX analysis further uncovers the presence of several other groups of phytoplankton, the presence of which is yet to be reported in many other tropical estuaries. It includes chrysophytes, cyanobacteria, prasinophytes, prymnesiophytes and chlorophytes. The appearance of phytoplankton groups at various stages of the monsoon was recorded, and this data is discussed in relation to environmental changes in the Mandovi estuary during the monsoon season.
