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1.

Ecological half-lives of radiocesium were observed on Izu-Oshima Island, Japan, a place which experiences typhoons annually. The estimated ecological half-lives (uncertainty) based on the observations above an asphalt and a bare surface were 1.6 year (31.6%) and 1.9 year (14.4%), respectively; those of 134Cs and 137Cs in soil were 1.5 year (7.2%) and 4.0 year (5.9%), respectively. The radiation level was quickly returned to the original level compared to other locations that do not experience such typhoon activity.

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2.
The preparation of 2-(4-fluorobenzyl)-6-(4-methoxyphenyl)-5-morpholin-1-ylmethyl imidazo[2,1-b][1,3,4]thiadiazole via the intermediate 2-(4-fluorobenzyl)-6-(4-methoxyphenyl)Imidazo[2,1-b][1,3,4] thiadiazole is described. Elemental analysis, IR spectrum, 1H NMR and X-ray crystal structure analyses were carried out to determine the compositions and molecular structures of the two compounds. The crystal packing exhibits intermolecular C–H?O, C–H?N, C–H?F and π–π stacking interactions leading to the formation of the supramolecular network.  相似文献   
3.
Physics of the Solid State - The electronic structure and optical properties of a binary intermetallic FeSb2 compound are studied. The calculations of the band structure, that demonstrate the...  相似文献   
4.
It has been demonstrated that the Filtered-x Wilcoxon LMS (FxWLMS) based adaptive filter mitigates the effect of the outliers acquired by the microphone signal of hearing aids by minimizing the Wilcoxon norm and hence shows better cancellation performance than the existing Filtered-x LMS (FxLMS) algorithm. The prediction error method based adaptive feedback canceller (PEMAFC) reduces the bias present in the estimate of the feedback path due to the continuous adaptive filtering (CAF). However, the impulse response of the measured feedback path is close to zero for the first many samples due to the delay introduced by ADC converters and then contains few significant values, which results in slow convergence rate when an adaptive filter is used to model the same. To overcome this limitation, we propose a proportionate normalized WLMS (PNWLMS) algorithm based PEMAFC (P-PNWLMS) for feedback cancellation in hearing aid in the presence of outliers. Further, with an objective to improve the convergence rate and performance accuracy simultaneously, this paper proposes a novel convex PNWLMS (CPNWLMS) algorithm which incorporates convex combination of PNWLMS and WLMS algorithms. The weight update equations are derived for PEMAFC trained by PNWLMS (P-PNWLMS) and CPNWLMS (P-CPNWLMS) algorithms respectively. The results of the simulation study show improved performance of the proposed CPNWLMS based adaptive filter over its component filters.  相似文献   
5.
Identification of factors which can influence the natural attenuation process with available microbial genetic capacities can support the bioremediation which has been viewed as the safest procedure to combat with anthropogenic compounds in ecosystems. With the advent of molecular techniques, assimilatory capacity of an ecosystem can be defined with changing community dynamics, and if required, the essential genetic potential can be met through bioaugmentation. At the same time, intensification of microbial processes with nutrient balancing, expressing and enhancing the degradative capacities, could reduce the time frame of restoration of the ecosystem. The new concept of ecosystems biology has added greatly to conceptualize the networking of the evolving microbiota of the niche that helps in effective application of bioremediation tools to manage pollutants as additional carbon source.  相似文献   
6.
Understanding the energy loss mechanisms in hot and dense QCD matter is an important aspect of phase diagram exploration at the Relativistic Heavy Ion Collider (RHIC). A wide variety of experimental studies are devoted to this subject. With the start of the experimental program at the Large Hadron Collider (LHC) such studies will be taken to a new energy domain lending to crucial new insights on the properties of the new state of matter. We investigate the possibility of utilizing di-hadron correlation techniques for probing the medium created in heavy ion collisions at the 5.5 TeV with a generic hadron detector. We discuss characterization of the jet yields, fragmentation functions, and energy estimates on near- and away- sides in triggered di-hadron correlations.  相似文献   
7.
In this paper, we initiate the study of the method of upper and lower solutions and monotone iterative technique for impulsive differential equations with variable moments. Because of the difficult nature of the problem, we shall restrict ourselves to a simple situation which, as we shall see, presents enough complications.  相似文献   
8.
In this paper we study Euler solutions, strong and weak invariance of solutions for fractional differential equations.  相似文献   
9.
In this paper, we develop the monotone iterative technique for periodic boundary value problems with causal operators.  相似文献   
10.
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