排序方式: 共有21条查询结果,搜索用时 15 毫秒
1.
Bulk superconducting samples of type Tl0.5Pb0.5Sr1.6Ba0.4CaCu2−x
Ru
x
O7−δ, (Tl, Pb)/Sr-1212, with 0.0 ≤ x ≤ 0.525 were prepared by the conventional one-step solid-state reaction technique. The prepared samples were investigated
using X-ray powder diffraction, electrical resistivity and electron paramagnetic resonance (EPR) measurements. Enhancement
of the phase formation, superconducting transition temperature T
c and hole carriers concentration P was observed up to x = 0.075. For x > 0.075, a reverse trend was observed. EPR spectra were measured at different temperatures (120–290 K) for all prepared samples.
The number of spins N participating in the resonance and the paramagnetic susceptibility χ were calculated as a function of both Ru-content and
temperature. N and χ increased as the Ru-content increased. A linear relationship between logN and 1/T was established, from which the activation energy E
a was calculated as a function of the Ru-content. The temperature dependence of χ was fitted according to Curie–Weiss type
of magnetic behavior. Curie constant C, Curie temperature θ, the effective magnetic moment μ and the electronic specific heat γ were estimated as a function of the Ru-content. 相似文献
2.
S. Mordechai H.T. Fortune G.E. Moore M.E. Cobern R.V. Kollarits R. Middleton 《Nuclear Physics A》1978,301(3):463-476
The reaction 12C(t, p)14C has been investigated with an 18 MeV triton beam. Twenty energy levels of 14C were identified up to 13 MeV excitation. Angular distributions were measured and compared with DWBA calculations. A previously unreported 0+ level at 9.75 MeV was observed; it undoubtedly corresponds to the second predominantly sd shell 0+ state in 14C. Additional spin and parity assignments have been made in the present work: 9.81 MeV, (1?); 10.43 MeV, 2+; 10.50 MeV, (3?); 10.74 MeV, 4+; 11.40 MeV, 1?; 11.67 MeV, (1?); 11.73 MeV, (5?); 12.58 MeV, (2+, 3?); 12.87 MeV. 2+, 3?; and 12.96 MeV, (1?); none of which had a definite spin and parity assignment previously. Our results confirm the previous information on the level structure of 14C below 8.5 MeV. The cross section for the unnatural parity state at 7.34 MeV, Jπ = 2?, is well reproduced by a two-step reaction calculation. The results are compared with the predictions of a weak coupling model. 相似文献
3.
ABSTRACTBayfol (PC-PBT blend ?lm) is a class of polymeric solid-state nuclear track detector which has a lot of applications in several radiation detection ?elds. It is a bisphenol-A polycarbonate PC blended with polybutylene terephthalate PBT. Bayfol/Palladium (PC-PBT/Pd) nanocomposite films have been deposited using the molding technique. It is worth mentioning that this report is almost the first one dealing with the topic of the changes of physical properties of Bayfol/Pd nanocomposite due to laser exposure. Samples from PC-PBT/Pd (5?wt%) nanocomposite were exposed to IR-pulsed laser of 5-W power, capable of producing 2000 pulses per second with pulse duration of 200?ns at 904?nm. The laser fluences were in the range 2–25?J/cm2. The resultant modi?cations in the exposed nanocomposite samples have been studied as a function of fluence using different characterization techniques such as X-ray diffraction (XRD), UV spectroscopy and color difference studies. The results indicate the proper dispersion of Pd nanoparticles in the PC-PBT matrix that causes a strong intermolecular interaction between Pd and PC-PBT, resulted in an increase in refractive index and the amorphous phase. Also, it is found that the laser exposure reduces the optical energy gap that could be attributed to the increase in structural disorder of the exposed PC-PBT/Pd nanocomposites due to crosslinking. Further, the color intensity ΔE, which is the color difference between the exposed samples and the non-exposed one, was increased with increasing the laser fluence, convoyed by a significant increase in the green and yellow color components. 相似文献
4.
5.
6.
羧甲基纤维素钠水凝胶的制备及其生物降解性研究 总被引:9,自引:0,他引:9
用羧甲基纤维素钠(CMC—Na)制得了含水量高达98%的水凝胶,考察了防腐剂、交联剂、无机态氮素、有机态氮素、碳水化合物的加入量以及环境中pH值等因素对生物降解性的影响。结果表明:制备条件不同,水凝胶的生物降解性不同;环境中一定量铵根离子的存在有利于水凝胶的生物降解;在pH=5.2的环境中纤维素酶活性最高,降解程度最大。 相似文献
7.
8.
Ratios of cross sections in 41Ca(d,p) and 38Ar(6Li,d) leading to 0+ states of 42Ca allow determination of the coefficients in wave functions of the type a(2p)+b(4p?2h) + c(6p?4h), and an independent evaluation of the intrinsic amplitude for (sd)2(fp)2 and (fp)4 α transfer. 相似文献
9.
H. T. Fortune R. Middleton M. E. Cobern G. E. Moore S. Mordechai R. V. Kollarits 《Physics letters. [Part B]》1977,70(4):408-410
The 14C(t, p)16C reaction locates five new states in 16C, at excitation energies of 3120 ± 15, 3983 ± 10, 4136 ± 10 and 6109 ± 15 keV, in addition to the g.s. and 1.76 MeV states. The 3.02 and 3.98 MeV states appear to be the second 0+ and 2+ 2p-2h states, respectively. The 4.14 MeV state has Jπ = 4+ and the 6.11 MeV state has Jπ = 2+, 3−, or 4+. 相似文献
10.
Salah E. M. Eltom Ahmed A. H. Abdellatif Hamzah Maswadeh Mohsen S. Al-Omar Atef A. Abdel-Hafez Hamdoon A. Mohammed Eiman ME. Agabein Ibrahim Alqasoomi Salem A. Alrashidi Mohammed S. M. Sajid Mugahid A. Mobark 《Molecules (Basel, Switzerland)》2021,26(12)
The ostrich oil of Struthio camelus (Ratite) found uses in folk medicine as an anti-inflammatory in eczema and contact dermatitis. The anti-inflammatory effect of a γ-lactone (5-hexyl-3H-furan-2-one) isolated from ostrich oil and its formulated nano-emulsion in formalin-induced paw edema was investigated in this study. Ostrich oil was saponified using a standard procedure; the aqueous residue was fractionated, purified, and characterized as γ-lactone (5-hexyl-3H-furan-2-one) through the interpretation of IR, NMR, and MS analyses. The γ-lactone was formulated as nano-emulsion using methylcellulose (MC) for oral solubilized form. The γ-lactone methylcellulose nanoparticles (γ-lactone-MC-NPs) were characterized for their size, shape, and encapsulation efficiency with a uniform size of 300 nm and 59.9% drug content. The γ-lactone was applied topically, while the formulated nanoparticles (NPs) were administered orally to rats. A non-steroidal anti-inflammatory drug (diclofenac gel) was used as a reference drug for topical use and ibuprofen suspension for oral administration. Edema was measured using the plethysmograph method. Both γ-lactone and γ-lactone-MC-NPs showed reduction of formalin-induced paw edema in rats and proved to be better than the reference drugs; diclofenac gel and ibuprofen emulsion. Histological examination of the skin tissue revealed increased skin thickness with subepidermal edema and mixed inflammatory cellular infiltration, which were significantly reduced by the γ-lactone compared to the positive control (p-value = 0.00013). Diuretic and toxicity studies of oral γ-lactone-MC-NPs were performed. No diuretic activity was observed. However, lethargy, drowsiness, and refusal to feeding observed may limit its oral administration. 相似文献