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The PL/PK method of determining the ?-capture decay energy fails badly in the case of 113Sn. We suggest that the discrepancies in the measured values may be due to variable amounts of 250 d 119Snm present in the 115 d 113Sn samples.  相似文献   
2.
We have carried out measurements on the decay of 119In isomers and the 118Sn(n, γ) reaction to supplement Coulomb excitation measurements on 119Sn. In addition to the 311.39 keV isomeric transition in 119In, we observed 13 γ-rays in 119Sn from the decay of the 2 min and 18 min 119In isomers. These γ-rays have been incorporated into a level scheme of 119Sn with levels at 0, 23.867, 89.54, 787.01, 920.5, 921.4, 1089.5, 1187.76, 1249.67, 1304.44 and 1354 keV. Conclusive evidence for the existence of a 920.5–921.4 keV, 32+-52+ level doublet was obtained from capture γ-ray measurements of resonance energy neutrons.  相似文献   
3.
Ammonium ionic liquids with the 4-chloro-2-methylphenoxyacetate anion were synthesized and characterized. Physicochemical properties, such as thermal stability, phase transition temperatures, viscosity, density, refractive index, as well as surface activity and herbicidal activity were determined. Improved physicochemical properties suggest a reduced environmental impact of newly formed group of herbicidal ionic liquids (HILs). HILs with a longer substituent can be characterized with better herbicidal activity in comparison with commercial products.  相似文献   
4.
The lifetimes of the 4s4p 3 P 1 and 4s3d 1 D 2 metastable states of Ca have been studied using the time-of-flight technique. Two kinds of observations were performed. First, the exponential decay of the fluorescence, using a (continuous) dc discharge for excitation and then the velocity distribution of the radiating atoms, using a pulsed discharge, were measured. From the combined results of these measurements the lifetimes were derived. The lifetimes of the 4s4p 3 P 1 and 4s3d 1 D 2 states of Ca are determined to be 0.57±0.03 ms and 1.5±0.4 ms, respectively.  相似文献   
5.
It is well known that the observation of a nonzero Fermi matrix element for a β-transition between states that differ in isospin can provide information about the relative isospin purity of the states involved. We have determined the log ft value for the 0+ → 0+ (ΔT ≠ 0) β-transition in 64Ga64Zn decay as 6.516 ± 0.020. From this log ft value, we have deduced |MF| = (43.4 ± 1.1) × 10?3, |α| = (21.7 ± 0.6) × 10?3 and |〈VCD〉| = 41.7 ± 1.1 keV, where MF2 and 〈VCD〉 represent the Fermi matrix element, isospin impurity and Coulomb matrix element, respectively. The Coulomb matrix element of 41.7 keV found for 64Ga is one of the largest known from β-decay experiments. The experimental procedure involved a careful measurement of the intensity of the annihilation radiation relative to that of the other γ-rays from 64Ga decay. As a by-product, we have obtained an improved 64Ga decay scheme. We have also summarized the existing information on the isospin impurities of nuclear states as deduced from β-decay experiments.  相似文献   
6.
In this paper, we show that sweet quaternary ammonium, pyridinium, and imidazolium cyclamates are cheap, thermally stable, surface and biologically active ionic liquids, with potential application as feeding deterrents.  相似文献   
7.

The influence of selected types of ammonium ionic liquid (AIL) additives on corrosion and functional parameters of lead-acid battery positive electrode was examined. AILs with a bisulfate anion used in the experiments were classified as protic, aprotic, monomeric, and polymeric, based on the structure of their cation. Working electrodes consisted of a lead-calcium-tin alloy utilized in the industry for manufacturing current collectors of positive electrodes in lead-acid batteries (LABs). This alloy was used in the first part of the study for the evaluation of corrosion intensity and stability of electrolyte with AIL additives. In the second part, the grid made of the examined alloy was covered with positive active mass, the composition of which was modified by selected AIL. The selection of an appropriate substance was made based on parameters such as corrosion potential, corrosion current, polarization resistance, and hydrogen and oxygen evolution potentials. Techniques such as linear sweep voltammetry, corrosimetry, and electrochemical impedance spectroscopy were used. The conducted measurements revealed that polymeric AIL additive had an exceptionally positive influence on the inhibition of the corrosion process in LAB and electrochemical window of the electrolyte. The influence of this compound on the specific capacity and resistance of the active mass was also discussed.

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