نتایج جستجو برای: pb

تعداد نتایج: 36420  

2015
Sha Yang Yun Liu

The nuclear volume effects (NVEs) of Hg, Tl and Pb isotope systems are investigated with careful evaluation on quantum relativistic effects via the Dirac's formalism of full-electron wave function. Equilibrium (202)Hg/(198)Hg, (205)Tl/(203)Tl, (207)Pb/(206)Pb and (208)Pb/(206)Pb isotope fractionations are found can be up to 3.61‰, 2.54‰, 1.48‰ and 3.72‰ at room temperature, respectively, larger...

Journal: :Environmental science and pollution research international 2012
Xiao Shu LiYan Yin QuanFa Zhang WeiBo Wang

BACKGROUND Cuttings and seedlings of Jatropha curcas L. were exposed to different regimes of lead (Pb) stress as Pb(NO₃)₂ at 0 (CK), 0.5, 1, 2, 3, and 4 mM kg⁻¹ soil. OBJECTIVES The effect of Pb treatment on the root length, tolerance index, photosynthetic pigments, photosynthetic activity, lipid peroxidation, and antioxidant enzyme was studied in a greenhouse pot experiment. RESULTS The re...

Journal: :Analytical chemistry 2013
Jeremy J Bellucci Antonio Simonetti Christine Wallace Elizabeth C Koeman Peter C Burns

The Pb isotopic compositions for 51 spots of melt glass in 11 samples of trinitite have been determined by laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS). Trinitite glass yields a large range of Pb isotopic compositions (i.e., (206)Pb/(204)Pb = 17.08-19.04), which reflect mixing between industrial Pb from materials used in the Trinity test and natural ...

Journal: :Physical review letters 2013
T Keiber F Bridges B C Sales

PbTe is a well-known thermoelectric material. Recent x-ray total scattering studies suggest that Pb moves off center along 100 in PbTe, by ∼0.2  Å at 300 K, producing a split Pb-Te pair distribution. We present an extended x-ray absorption fine structure spectroscopy (EXAFS) study of PbTe (and Tl doped PbTe) to determine if Pb or Te is off center. EXAFS provides sensitive r- or k-space phase in...

2007
J. M. Liotard

The activity of the Damavand volcano (Central Alborz, northern Iran) began 1.8 Ma ago and continued up to 7 ka BP. Although the volcanic suite is clearly of shoshonitic affinity, only two petrographic types can be distinguished in the studied lavas: (1) weakly differentiated absarokites (49 < %SiO2 < 51), scattered around the volcano but with a regional extension, (2) highly differentiated bana...

2014
Yongmei Xiao Hongjun Fu Xiaojie Han Xiaoxia Hu Huaiyu Gu Yilin Chen Qing Wei Qiansheng Hu

Lead (Pb) is found to impair cognitive function. Synaptic structural plasticity is considered to be the physiological basis of synaptic functional plasticity and has been recently found to play important roles in learning and memory. To study the effect of Pb on spatial learning and memory at different developmental stages, and its relationship with alterations of synaptic structural plasticity...

Journal: :International journal of environmental research and public health 2016
Brian Gulson Michael Korsch Anthony Bradshaw

Concerns have been expressed that dust from the minerals processing facilities at Karumba Queensland Australia have resulted in elevated lead (Pb) concentrations in rain water tanks. The ores derived from the Century mine some 304 km from the port. High precision Pb isotopic measurements on environmental samples have been undertaken to evaluate the source of Pb in rainwaters and acid digests fr...

Journal: :The Journal of comparative neurology 2009
Tyler Fortune Diana I Lurie

Low-level lead (Pb) exposure is associated with behavioral and cognitive dysfunction, but it is not clear how Pb produces these behavioral changes. Pb has been shown to alter auditory temporal processing in both humans and animals. Auditory temporal processing occurs in the superior olivary complex (SOC) in the brainstem, where it is an important component in sound detection in noisy environmen...

2011
Sebastian N. White

The ATLAS detector is capable of resolving the highest energy pp collisions at luminosities sufficient to yield 10’s of simultaneous interactions within a bunch collision lasting <0.5 nsec. Already in 2011 a mean occupancy of 20 is often found in pp running. In 2004 studies by ATLAS showed that the detector would have excellent performance also for the foreseeable particle multiplicities in the...

1999

Chelates have been shown to enhance phytoextraction of Pb from contaminated soil. Mechanisms behind this phenomenon, however, remain largely unexplored. In this paper we examine chelate effect on Pb dissolution, plant Pb uptake, and internal plant Pb translocation. EDTA was found to be the most efficient in increasing watersoluble Pb concentration in our test soil. Unfortunately, PbEDTA is high...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید