Black pine (Pinus nigra) barks: A critical evaluation of some sampling and analysis parameters for mercury biomonitoring purposes

Abstract Tree barks are increasingly used as biomonitors of airborne pollutants. However, many authors stress the poor comparability of the results achieved in different studies. This drawback is mainly caused by a poor understanding of the critical sampling parameters to be considered. To minimize the biases that could be introduced during sampling, in this study the barks of Pinus nigra J.F. Arnold from thirteen sites were investigated in the abandoned Mt. Amiata mercury (Hg) mining district (Southern Tuscany, Italy) and surroundings. The influence of some sampling and analyzing parameters on Hg content was critically assessed. At each site, a total of eight bark samples were taken from a single tree at two heights (70 cm and 150 cm from soil) and at four different sides of the trunk, corresponding to the four cardinal directions; a composite soil sample was also collected. Mercury contents in barks range from 0.1 to 28.8 mg/kg, and are correlated with soil Hg contents (1–480 mg/kg), indicating that barks record both gaseous Hg concentrations in air, and wind-transported Hg-bearing particulate. For each tree, samples at 70 cm and 150 cm show Hg contents of the same order of magnitude, even if values for 150 cm are slightly less dispersed, possibly because barks at 70 cm are more influenced by random soil particles. There is no statistically significant dependence of Hg content on direction and tree age. Simulated rain events cause a negligible loss of Hg from barks. Results suggest that a convenient sampling practice for Pinus nigra is to collect a bark slice (typically 1–2 mm) within the outermost 1.5 cm layer

P E N G A R U H K O M P E N S A S I D A N D I S I P L I N K E R J A T E R H A D A P K I N E R J A G U R U D I S M A N 1 J A T I S A R I K A B U P A T E N K A R A W A N G

A B S T R A K P e n e l i t i a n i n i b e r t u j u a n u n t u k m e n g e t a h u i p e m b e r i a n K o m p e n s a s i , k o n d i s i D i s i p l i n K e r j a d a n K i n e r j a G u r u , s e r t a u n t u k m e n g e t a h u i s e b e r a p a b e s a r p e n g a r u h v a r i a b e l K o m p e n s a s i d a n D i s i p l i n K e r j a t e r h a d a p K i n e r j a G u r u b a i k s e c a r a s i m u l t a n m a u p u n s e c a r a p a r s i a l d i S M A N e g e r i 1 J a t i s a r i K a b u p a t e n K a r a w a n g . S a m p e l d a l a m p e n e l i t i a n i n i j u m l a h s e l u r u\ud h p o p u l a s i y a n g b e r j u m l a h 4 9 G u r u . M e t o d e p e n e l i t i a n y a n g d i g u n a k a n a d a l a h a n a l i s i s r e g r e s i b e r g a n d a , a n a l i s i s k o r e l a s i b e r g a n d a , a n a l i s i s k o e f i s i e n d e t e r m i n a s i s i m u l t a n d a n p a r s i a l . H a s i l p e n e l i t i a n m e n u n j u k k a n b a h w a k o m p e n s a s i y a n g d i b e r i k a n m a s i h t e r m a s u k k a t e g o r i c u k u p , m e n g e n a i d i s i p l i n k e r j a s e c a r a u m u m r e s p o n d e n m e n y a t a k a n d a l a m k a t e g o r i c u k u p , d a n k i n e r j a g u r u b e r a d a p a d a k a t e g o r i c u k u p . K o m p e n s a s i d a n D i s i p l i n K e r j a s e c a r a s i m u l t a n m a u p u n p a r s i a l b e r p e n g a r u h s i g n i f i k a n t e r h a d a p K i n e r j a g u r u . S e c a r a s i m u l t a n p e n g a r u h n y a a d a l a h 8 1 , 9 % d a n s i s a n y a 1 8 , 1 % d i p e n g a r u h i o l e h v a r i a b e l l a i n . V a r i a b e l y a n g b e r p e n g a r u h d o m i n a n a d a l a h K o m p e n s a s i . K a t a K u n c i : K o m p e n s a s i , D i s i p l i n K e r j a , d a n K i n e r j a G u r

The Electronics and Data Acquisition System of the DarkSide Dark Matter Search

It is generally inferred from astronomical measurements that Dark Matter (DM) comprises approximately 27\% of the energy-density of the universe. If DM is a subatomic particle, a possible candidate is a Weakly Interacting Massive Particle (WIMP), and the DarkSide-50 (DS) experiment is a direct search for evidence of WIMP-nuclear collisions. DS is located underground at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, and consists of three active, embedded components; an outer water veto (CTF), a liquid scintillator veto (LSV), and a liquid argon (LAr) time projection chamber (TPC). This paper describes the data acquisition and electronic systems of the DS detectors, designed to detect the residual ionization from such collisions

An availability study for a SME

A case study of an availability analysis for a small commercial company is presented. The analysis was carried out to meet a customer requirement for the availability of an electronic ground-based system in a benign environment. Availability calculations were based on failure data provided and an explanation of the methodology and problems encountered and dealt with are discussed. The methodology includes failure classification according to MIL-HDBK-781A and how it may be used to promote and develop internal processes. A commentary on the background to reliability/availability specification is provided and a number of recommendations for monitoring reliability and availability are given

Anomalous wind circulation over Taipei, Taiwan during the northern winter seasons of 2004 and 2005- A case study

This research reports, for the first time, an anomalous wind circulation over Taipei (Latitude 25.030N, Longitude 121.510E), Taiwan during the northern hemisphere winter season (December, January, and February) of years 2004 and 2005. The anomalous wind circulation of meridional winds, which showed southward directions during the winter seasons of 2004 and 2005 instead of northward winds, is noticed from one kilometer altitude range (lower troposphere) and that trend continued till around 20 km altitude range (lower stratosphere). To ascertain whether such a disturbed nature of wind pattern existed over nearby locations to Taipei, we have analyzed radiosonde-measured meridional and zonal winds over four nearby stations station to Taipei including, Roig, Xiamen, Minami and Fuzhou. Surprisingly, no anomalous wind behavior is seen except over Taipei during the northern winter seasons of 2004 and 2005. On the other hand, the European Centre for Medium-Range Weather Forecasts (ECMWF) model-predicted winds do not show any anomalous wind patterns over Taipei and other nearby stations, possibly due to the large averaging of internal variabilities of reanalysis databases. The plausible physical mechanisms of these disturbed meridional wind patterns are not understood at this juncture, but it is believed that local winds and atmospheric pollutants might have created an amicable environment as to provide such a disturbed meridional wind pattern over Taipei, Taiwan in the winter season of 2004 and 2005