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61.
The levels of 124In, which are populated in the decay of 124Cd, have been investigated at the OSIRIS on-line facility by means of conversion electron and γ-ray spectroscopy. A γ-γ coincidence measurement combined with the deduced transition intensities permitted construction of a unique level scheme. The half-life of the 243 keV level of 124In has been determined to be 50 ± 6 ns by the method of delayed coincidences. 相似文献
62.
Kuppuswamy Nagarajan Sharada J. Shenoy Hans Fritz Othmar Hosang Wilhelm J. Richter 《Helvetica chimica acta》1985,68(4):900-902
The reaction of anthranilamide with phosphorus pentasulfide in boiling pyridine leads to the benzodiazaphosphorine-pyridine salt 2 . The structure is established by elemental analysis, 1H- 13C- 15N- 31P-NMR, and mass spectral data. 相似文献
63.
A comparative study of the Chevrel phases Mo6S8, Mo6Se8, PbMo6S8 and Cu1.8Mo6S8 is made by the positron angular correlation technique at room temperature. Electronic properties like the number of conduction electrons per cluster, the density of states at the Fermi level, the electron effective masses and the Fermi velocities are obtained within the framework of the free electron model. The results are discussed in terms of available theoretical and other experimental data. 相似文献
64.
65.
Two protocols for the efficient transformation of aromatic as well as aliphatic primary carboxamides to the corresponding carbamates and aromatic as well as aliphatic cyclic imides to the corresponding anthranilic acid derivatives & amino acid derivatives, respectively, are described. We also developed a novel methodology to the multigram scale synthesis of gabapentin and (S)-pregabalin. The gabapentin methyl carbamate was converted to novel potential peptide prodrugs of gabapentin. 相似文献
66.
Lempel-Ziv complexity (LZ) [J. Ziv, A. Lempel, On the complexity of finite sequences, IEEE Trans. Inform. Theory 22 (1976) 75-81] and its variants have been used widely to identify non-random patterns in biomedical signals obtained across distinct physiological states. Non-random signatures of the complexity measure can occur under nonlinear deterministic as well as non-deterministic settings. Surrogate data testing have also been encouraged in the past in conjunction with complexity estimates to make a finer distinction between various classes of processes. In this brief letter, we make two important observations (1) Non-Gaussian noise at the dynamical level can elude existing surrogate algorithms namely: Phase-randomized surrogates (FT) amplitude-adjusted Fourier transform (AAFT) and iterated amplitude-adjusted Fourier transform (IAAFT). Thus any inference nonlinear determinism as an explanation for the non-randomness is incomplete (2) Decrease in complexity can be observed even across two linear processes with identical auto-correlation functions. The results are illustrated with a second-order auto-regressive process with Gaussian and non-Gaussian innovations. AR(2) processes have been used widely to model several physiological phenomena, hence their choice. The results presented encourage cautious interpretation of non-random signatures in experimental signals using complexity measures. 相似文献
67.
In recent days, humans are easily exposed to many work-related health issues. N-nitrosodiethylamine (NDE), which is considered to be a harmful carcinogenic agent released from rubber-based industries imparts a long-lasting effect on human health and immunity system. The current research investigates the ability of the two-dimensional nanomaterial, blue phosphorene nanosheet (BPNS) to detect the presence of NDE in the environment. Besides, the electronic and structural characteristics of BPNS are initially explored and NDE target vapour is permitted to interact with the chief component, BPNS. We have also designed blue phosphorene device to study the adsorption properties of NDE vapours based on current–voltage characteristics. The adsorption attributes are accounted for the target vapour adsorbed chief component, the results suggest that BPNS can be employed in detecting NDE vapours. 相似文献
68.
The asymmetric synthesis of both the enantiomer of chiral amines from the single chiral source of N-tert-butylsulfinylaldimines (3) by simply changing the organometallic reagents through diastereoselective addition. An efficient enantioselective synthesis of chiral amines including (S)-3-methyl-1-(2-piperidin-1-yl-phenyl)butyl amine (6a), a key intermediate to prepare antidiabetic drug repaglinide (1), is reported. 相似文献
69.
A novel anionic trinuclear linear copper(Ⅱ) complex {[Et3NH][Cu1.5(CH3COO)-(TTA)3]}2(1,TTA = 2-thenoyltrifluoroacetonate) has been synthesized in a direct reaction involving copper(Ⅱ) acetate monohydrate,TTA and excess triethylamine base in dichloromethane solvent.Green colored X-ray quality crystals of 1 were grown from n-hexane solvent at room temperature.The data were collected at 100 K.Compound 1 crystallizes in the monoclinic P21/n space group(a = 11.2141(8),b = 19.0965(13),c = 17.3680(14) ,β = 90.225(2)°,V = 3719.3(5) 3,Mr = 1840.14,Dc = 1.643 Mg/m3,F(000) = 1866,μ = 1.129 mm-1 and Z = 2).The asymmetric unit of 1 contains two copper atoms,one of which lies on a crystallographic inversion center with 50% occupancy. 相似文献
70.
Jeyakumar Nagarajan Narayanasamy Bose 《Journal of Thermal Analysis and Calorimetry》2020,139(1):475-487
Journal of Thermal Analysis and Calorimetry - The solid–liquid equilibria (SLE) of two binary mixtures of organic stabilizers for energetic materials, viz.... 相似文献