排序方式: 共有27条查询结果,搜索用时 31 毫秒
1.
John L. Wood Johannes Schwarzenberg Edward F. Zganjar Dubravka Rupnik 《Hyperfine Interactions》1992,75(1-4):51-58
State-of-the-art spectroscopy of nuclei far from stability has achieved an extraordinary level of sophistication and detail
in the last ten years. In principle, if a state can be populated, it can be characterized by its energy, spin, parity, and
major decay paths. Sometimes its lifetime can be measured. In practice, one is confronted with enormous complexity. To convert
raw spectroscopic data into nuclear structure data involves a complex process of disentangling gamma rays and conversion electrons
into decay schemes. Specifically, coincidence techniques, especially coincidence intensities, play a crucial role in this
process. Recent examples and methods from work done at UNISOR are presented. 相似文献
2.
Y. Xu K. S. Krane M. A. Gummin J. L. Wood M. M. Jarrio J. B. Breitenbach E. F. Zganjar D. Rupnik H. K. Carter P. F. Mantica Jr. B. E. Zimmerman 《Hyperfine Interactions》1992,75(1-4):481-487
The184Au→184Pt decay, studied on-line with the UNISOR facility at HHIRF, is discussed. Gamma-ray and conversion-electron spectroscopy
of184Pt as well as on-line nuclear orientation measurements of184Au were done. A new low-lying level scheme of184Pt is proposed. Two coexisting bands with different deformations and their respective γ-vibrational bands are established.
Internal conversion coefficients for interband transitions between states with the same spin are extracted from the spectroscopy
measurements. The relative E0 contents of the transitions are determined by combining internal conversion coefficients with
E2/M1 mixing ratios deduced from gamma-ray anisotropies measured from oriented nuclei. 相似文献
3.
In this paper, we demonstrate how to apply recently discovered ferromagnetic nematic liquid crystal for visualisation of magnetic fields. The material exhibits strong optical response to both external electric and magnetic fields, which gives us an opportunity to use it for the detection of an area of magnetic vector field in a way that both, the magnitude and the direction of a given field can be simultaneously measured. We discuss the physical model that describes the behaviour of ferromagnetic liquid crystal placed in a liquid crystal cell and demonstrate the method of extracting the information about an arbitrary magnetic field from the combination of magneto-optic and electro-optic response of the sample placed in that field. We have applied the principle to a special case, where magnetic field was visualised on a 2D area near a cylindrical permanent magnet. 相似文献
4.
Auerbach LB Burman RL Caldwell DO Church ED Cochran AK Donahue JB Fazely AR Garvey GT Gunasingha RM Imlay RL Kahrimanis G Louis WC Majkic R Malik A McIlhany KL Metcalf WJ Mills GB Rupnik D Sandberg VD Smith D Somodi RF Stancu I Strossman WD Sung M Tayloe R VanDalen GJ Vernon W Wadia N White DH Yellin S Yi H;LSND Collaboration 《Physical review letters》2004,92(9):091801
We observe a net beam excess of 8.7+/-6.3(stat)+/-2.4(syst) events, above 160 MeV, resulting from the charged-current reaction of nu(micro) and/or nu;(mu) on C and H in the LSND detector. No beam-related muon background is expected in this energy regime. Within an analysis framework of pi(0)-->nu(mu)nu;(mu), we set a direct upper limit for this branching ratio of Gamma(pi(0)-->nu(mu)nu;(mu))/Gamma(pi(0)-->all)<1.6 x 10(-6) at 90% confidence level. 相似文献
5.
Z.B. Maksić K. Rupnik A. Veseli 《Journal of Electron Spectroscopy and Related Phenomena》1983,32(2):163-175
The solid-state binding energies of uracil and some of its derivatives have been calculated using semiempirical SCC-MO intramolecular potential expressed in the pointcharge approximation. The results are essentially in satisfactory agreement with experimental data, giving at the same time a simple and transparent interpretation of the ESCA spectra which is close to that suggested by chemical intuition. Splitting of some unresolved N 1 s peaks is proposed, and separate binding energies are attributed to particular nitrogen atoms. The relaxation energies are discussed briefly. The present and earlier evidence indicates that formal atomic charges are meaningful within the theoretical framework adopted, despite the fact that they cannot be defined in a unique fashion. 相似文献
6.
Z.B. Maksić K. Rupnik M. Eckert-Maksić 《Journal of Electron Spectroscopy and Related Phenomena》1979,16(3):371-377
The keto—enol tautomerism in malonaldehyde and some related 1,3-diketones is thoroughly discussed by the calculation of inner-core binding energies. The semiempirical wave-functions were obtained by the self-consistent charge (SCC—MO) molecular orbital procedure. The calculated O(1s) binding energies are generally in good agreement with available experimental data. The discrepancy found for the alcohol-type oxygen in acetylacetone is so large that it strongly indicates an error in experimental assignment. The calculations also provide conclusive evidence that enol-forms possess asymmetric hydrogen-bonded protons. 相似文献
7.
Synthesis of poly(ester‐amide) dendrimers based on 2,2‐Bis(hydroxymethyl) propanoic acid and glycine
David Pahovnik Anja Čusak Sebastjan Reven Ema Žagar 《Journal of polymer science. Part A, Polymer chemistry》2014,52(22):3292-3301
Water‐soluble, biodegradable, and biocompatible poly(ester‐amide) dendrimers with hydroxyl functional groups are synthesized from previously prepared AB2 adduct of 2,2‐bis(hydroxymethyl) propanoic acid (bis‐MPA) and glycine as a repeating unit. Two esterification procedures using different coupling reagent/catalyst systems (DCC/DPTS or EDC/DMAP) are studied with respect to efficiency, ease of products purification, and quality of the final products. Both procedures have their own benefits and drawbacks, depending on dendrimer generation. The synthesized poly(ester‐amide) dendrimers as well as commercially available bis‐MPA dendrimers, poly(ester‐amide) hyperbranched polymer, and poly(vinyl alcohol) are used for preparation of solid dispersions of sulfonylurea antidiabetic drug glimepiride to improve its poor water‐solubility. In vitro dissolution studies show in comparison with pure glimepiride in crystalline or amorphous form, to the same extent improved glimepiride solubility for solid dispersions based on dendritic polymers, but not for poly(vinyl alcohol). The amount of glimepiride complexed with both dendrimer types increases with dendrimer generation. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3292–3301 相似文献
8.
Sabina Markelj Zdravko Rupnik Iztok ade 《International journal of mass spectrometry》2008,275(1-3):64-74
A system has been developed for extracting near-zero kinetic energy H− and D− ions formed by dissociative electron attachment. It is the essential part of a new set-up for vibrational spectroscopy of hydrogen molecules. A magnetic field is used to collimate the probing electron beam. Ions produced by electron collision with the target molecules are collected by the combined action of this field and an electrostatic field penetrating into the interaction region. Highly effective extraction is achieved by taking into account the correct out-of plane displacement of ion trajectories which is usually neglected in similar arrangements. The extraction conditions are mass dependent so that by proper tuning, mass selection of detected ions is achieved. The new system is also used for detecting positive ions created by electron collisions with hydrogen atoms and molecules. 相似文献
9.
Sebastjan Glin?ek Iztok Ar?on Barbara Mali? Alojz Kodre Marija Kosec 《Journal of Sol-Gel Science and Technology》2012,62(1):1-6
The KTa0.6Nb0.4O3 sols for chemical solution deposition of thin films were prepared from potassium acetate and transition metal ethoxides by
the 2-methoxyethanol based route. The local environment of both transition metals after reflux times 1, 4, 24, and 48 h, whereby
the crystallization behavior of the films was strongly affected, was monitored by extended X-ray absorption fine structure
spectroscopy, at Ta L3 and Nb K edges. The Ta species existed in the sols as monomers, remaining stable even with prolonged reflux time. The Ta–O–K
correlations were confirmed in all cases. In contrast, the Nb-alkoxide formed dimers, with a gradual formation of oligomeric
species with prolonged refluxing. The Nb–O–K correlations were present after all reflux times. The number of K neighbours
around Nb increased upon refluxing, saturating at 24 h. 相似文献
10.
Gačnik Lojze Ambrožič Klemen Rupnik Sebastjan Radulović Vladimir Jaćimović Radojko 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(3):711-721
Journal of Radioanalytical and Nuclear Chemistry - We suspected that changes in the neutron spectrum, caused by varying control rod positions in routine steady state operation of our TRIGA nuclear... 相似文献