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1.
The decay of194Ir has been thoroughly studied resulting in the construction of a decay scheme consisting of 26 excited states and 69 transitions. Nine new levels and 29 new transitions were added to the previously known scheme. Of these, levels at 1,893.6 and 2,053.0 keV as well as 9γ-ray transitions are new to the194Pt level scheme. Preciseγ-ray energy and intensity measurements as well as quantitative coincidence measurements were performed, and the internal conversion spectrum was investigated with a Si(Li) detector. Directional correlation measurements were performed for selected cascades with the major result being the unique assignment of 0+ to the new level at 1,893.6 keV. The structure was interpreted within the framework of the PPQ model as well as the effective-core picture including nuclear triaxiality.  相似文献   

2.
The Japanese Environmental Agency (now the Ministry of the Environment) updated the environmental quality standards for noise in April 1999. The new standards replaced the median value of percentile level L50 for noise evaluation with the equivalent sound pressure level LAeq. The standards renewed the classification of areas and time sections. The most significant change was the introduction of category of artery-road-adjacent area.This report sets the range of the artery-road-adjacent area to 20 m or less from the applicable road to compare the new standards with the old, based on data collected in Nagoya City. The achieved rates for the new standards seem to be on the whole the same as those for the old standards. However, a detailed analysis reveals some differences, such as higher achieved rates in the artery-road-adjacent areas and lower achieved rates in the general areas for the new standards than for the old.  相似文献   

3.
Recently a lot of interest has been devoted to the study of order–disorder transitions in different materials. Although the equiatomic CuAu alloy represents a classical model of this type of transformation, it still receives considerable attention because many questions about phase transitions are still raised according to its equilibrium diagram. In this context, the present paper carries a new result observed in CuAu alloy consisting of a new anomaly observed on differential scanning calorimetry (DSC) curves at low temperature and new peaks in X-ray diffraction (XRD) spectra. For that, we will try to give an explanation of the origin of this new reaction, with the help of other techniques as electrical resistivity and microhardness measurements. The kinetic behaviour of this new reaction has been also studied by anisothermal analysis during DSC tests to estimate the kinetics parameters as activation energy E act and Avrami exponent n.  相似文献   

4.
A new variational principle based on the affine connection in space-time is proposed. This leads to a new formulation of general relativity. The gravitational field is a field of inertial frames in space-time. The metricg appears as a momentum canonically conjugate to the gravitational field. In the case of simple matter fields, e.g., scalar fields, electromagnetic fields, Proca fields, or hydrodynamical matter, the new formulation is equivalent to the traditional one. A new formulation of conservation laws is proposed.  相似文献   

5.
This paper introduces cyclostationary spectral analysis as a new approach to analyzing and predicting the aerodynamic noise generated by wind turbines. This method is able to reveal new insights into the periodic character of the noise signal and is therefore ideally suited to the study of wind turbine noise. A new formulation is presented for the time variation of the noise spectrum due to wind turbines thereby providing insight into the character of the periodic variation in noise referred to as ‘swishing’. The character and mechanism of swishing noise is analyzed in detail.  相似文献   

6.
In order to establish a new platform to manufacture micro-sized solid oxide fuel cells (SOFCs) with low operating temperatures, new design concepts, new preparation methods and new materials are being explored. Our studies in this paper are focused on the electrolyte material, and in particular gadolinia doped ceria (GDC), an electrolyte material, likely to replace the traditional yttria-stabilised zirconia (YSZ) for low temperature applications. GDC films were grown on a single crystal Si by pulsed laser deposition (PLD). The microstructure of the films as a function of growth time has been studied. We have found that the mean grain size increases with film thickness h as h2/5, in agreement with theoretical results.  相似文献   

7.
The difference between the theoretical and experimental values of the Goldberger-Treiman discrepancy may be explained by violation of e-ω universality, such as is likely to occur in unified gauge theories involving the new heavy lepton. We propose a new measurement of the πe2 decay rate as a test of this conjecture.  相似文献   

8.
A high resolution injector system has recently been installed at the Lund 3 MV tandem Pelletron accelerator. The new injector, designed mainly for 26Al ions, will increase the experimental potential of the Lund AMS facility considerably. High quality energy- and mass-resolution is obtained by using a 90° spherical electrostatic analyzer followed by a 90° magnetic analyzer. The injector is equipped with a high intensity sputtering source with a spherical ionizer. A new analytical technique for acceptance calculations as well as PC-based computational methods have been used in the design of the ion optical system of the new injector. Compared to our old injector system which has a magnetic analyzer with a bending angle of only 15°, the new system has a more than ten times better resolution. The beam optics of the new system is also better designed to match the accelerator acceptance. In this way the ion transmission from the ion source to the detector, for different ions of interest in our AMS programme, has been increased.  相似文献   

9.
The equations of electrodynamics for the interactions between magnetic moments are written on R×S3 topology rather than on Minkowskian space-time manifold of ordinary Maxwell's equations. The new field equations are an extension of the previously obtained Klein-Gordon-type, Schrödinger-type, Weyl-type, and Dirac-type equations. The concept of the magnetic moment in our case takes over that of the charge in ordinary electrodynamics as the fundamental entity. The new equations have R×S3 invariance as compared to the Lorentz invariance of Maxwell's equations. The solutions of the new field equations are given. In this theory the divergence of the electric field vanishes whereas that of the magnetic field does not.Research supported in part by the Colgate Research Council and by the Center for Theoretical Physics, University of Maryland.  相似文献   

10.
Partial wave dispersion relations in a new formulation and fixed-s dispersion relations are used to calculate the long range contributions to the real parts of πN amplitudes. Recent results from a double spectral function calculation are applied for constraining the imaginary parts. We propose to use the new partial waves as starting values in future phase shift analyses and to treat our prediction for the tail of high partial waves as part of the input. — The differences between our new partial waves and the Karlsruhe-Helsinki 80 and CMU-LBL 80 solutions are discussed. Concerning measurable quantities, the new parital waves lead to significant changes in the forward logarithmic slopes of differential cross sections. — Thel-dependence of our partial waves is discussed up to large values ofl. We find a systematic even-l, odd-l splitting at all energies.  相似文献   

11.
The new superspace of Wess and Zumino is generalized to the unconstrainedN-extendedD-dimensional case, it amounts actually to a reparametrization of the old superspace. Recurrence relations for the transformation law and for the covariant derivatives of the superfields defined in the new superspace are obtained. The definition of the component fields as local Lorentz covariant fields has the consequence that the gauge covariant expressions obtained for the vielbein and the connection of the new superspace don't contain the terms dropped out in the Wess-Zumino gauge of supergravity.  相似文献   

12.
A new non-equilibrium molecular dynamics algorithm is presented based on the original work of Müller-Plathe, (1997, J. chem. Phys., 106, 6082), for the non-equilibrium simulation of heat transport maintaining fixed the total momentum as well as the total energy of the system. The presented scheme preserves these properties but, unlike the original algorithm, is able to deal with multicomponent systems, that is with particles of different mass independently of their relative concentration. The main idea behind the new procedure is to consider an exchange of momentum and energy between the particles in the hot and cold regions, to maintain the non-equilibrium conditions, as if they undergo a hypothetical elastic collision. The new algorithm can also be employed in multicomponent systems for molecular fluids and in a wide range of thermodynamic conditions.  相似文献   

13.
The purpose of this paper is to develop an efficient approach for vibro-acoustic analysis. Being simple and representative, an exited plate-acoustic system is selected as a validation case for the vibro-acoustic analysis as the system presents one two-dimensional statistical component (modal dense structure panel—plate) connected to the other component (deterministic acoustic volume—cavity) through the area junction over a surface domain, rather than at a line boundary. Potential industrial applications of the system vibro-acoustic analysis would be in acoustic modelling of vehicle body panels such as the cabin roof panel, and door panels for the boom noise analysis.A new deterministic-statistical analysis approach is proposed from a combination or hybrid of deterministic analysis and statistical energy analysis (SEA) approaches. General theory of the new deterministic-statistical analysis approach is introduced. The main advantage of the new deterministic-statistical analysis approach is its possibility in place of the time consuming Monte Carlo simulation. In order to illustrate and validate the new deterministic-statistical analysis approach, three approaches of the deterministic analysis, the statistical energy analysis and the new deterministic-statistical analysis are then applied to conduct the plate-acoustic system modelling, and their results will be compared. The vibro-acoustic energy coupling characteristic of the plate-acoustic system will be studied. The most suitable frequency range for the new approach will be identified in consideration of computational accuracy, information and speed.  相似文献   

14.
 以Ar作压力介质,在0~23 GPa压力范围内,利用金刚石压腔装置(DAC)和激光加温技术,采用显微拉曼光谱进行原位测试,对处于准静水压力条件下的斜锆石开展高温高压相变研究。研究结果表明:室温下斜锆石ZrO2于3.4 GPa时开始发生相变,到10.4 GPa时其明显转变成一个空间群为Pbca的斜方相。此新相随着压力升高,直到15.3 GPa,仍稳定存在。通过研究,首次获得了Pbca相的拉曼谱图。随后在15.3 GPa压力下进行了激光加温后淬火,结果发现,加热前的Pbca相又转变成了空间群为Pnam的PbCl2结构类型的高压相,该相直到实验最高压力23 GPa仍稳定存在。  相似文献   

15.
In this work we report on new optically pumped THz laser lines from deuterated formic acid (DCOOD). An isotopic 13CO2 laser was used for the first time as a pump source for this molecule, and a Fabry–Perot cavity was used as a THz laser resonator. Optoacoustic absorption spectra were used as a guide to search for new THz laser lines. We could observe six new laser lines in the range from 303.8 μm (0.987 THz) to 725.1 μm (0.413 THz). The lines were characterized according to wavelength, relative polarization, relative intensity, and optimum working pressure. The transferred lamb-dip technique was used to measure the frequency absorption transition for both of these laser lines. Furthermore, we also present a catalogue of all THz laser lines generated from DCOOD.  相似文献   

16.
Abstract

Raman scattering, visible absorption, and optical observation studies have been made on polycrystalline potassium superoxide (KO2) in a diamond anvil cell as a function of pressure and temperature. Three new phases are observed. With increasing pressure at 298 K, KO2 transforms from the well known modified CaC2 structure (Phase II), to two new phases (VII, and VIII). The transformation from III to VII occurs at about 3.2GPa. Phase VII transforms to phase VIII at about 4.4GPa. However, in some samples phase VII does not occur and phase II transforms directly into phase VIII at about 4.2 GPa. These structural transformations are indicated by marked changes in the Raman spectrum. The transitions out of phase II are also marked by a discontinuous red shift in the optical absorption edge. From optical observations we have also determined the pressure and temperature dependence of the transitions from phase II to the high temperature cubic (B1) phase I as well as from the high pressure phases VII and VIII to a new nonbirefringent phase IX. This new phase IX has the cubic B2 (CsCl) structure as is shown by our recent X-ray synchrotron experiments.  相似文献   

17.
Science based on the unified concepts on matter at the nanoscale provides a new foundation for knowledge creation, innovation, and technology integration. Convergent new technologies refers to the synergistic combination of nanotechnology, biotechnology, information technology and cognitive sciences (NBIC), each of which is currently progressing at a rapid rate, experiencing qualitative advancements, and interacting with the more established fields such as mathematics and environmental technologies (Roco & Bainbridge, 2002). It is expected that converging technologies will bring about tremendous improvements in transforming tools, new products and services, enable human personal abilities and social achievements, and reshape societal relationships.After a brief overview of the general implications of converging new technologies, this paper focuses on its effects on R&D policies and business models as part of changing societal relationships. These R&D policies will have implications on investments in research and industry, with the main goal of taking advantage of the transformative development of NBIC. Introduction of converging technologies must be done with respect of immediate concerns (privacy, toxicity of new materials, etc.) and longer-term concerns including human integrity, dignity and welfare. The efficient introduction and development of converging new technologies will require new organizations and business models, as well as solutions for preparing the economy, such as multifunctional research facilities, integrative technology platforms, and global risk governance.  相似文献   

18.
氢气放电源打靶的较完整新谱系实验测量   总被引:3,自引:2,他引:1       下载免费PDF全文
 为了能够实现明确和清晰地同时测出氢气放电源打靶的较完整新谱系,使用氢气放电中的电子和X射线等直接打靶,在衍射角和测量角均为45°时,测量氢气放电源打靶的较完整新谱系。实验同时测到了3组6条氢气放电源打靶的新谱系,它们是:(2.25±0.07)和(2.56±0.08) keV;(3.25±0.10)和(3.62±0.11) keV;(4.42±0.13)和(4.79±0.15) keV。这6条新谱线表征了未知粒子的能级特性,是未知粒子存在的标志。未知粒子在靶中能储存一年以上,测得的未知粒子能级谱线能量为keV量级,氢气放电源中粒子为已知粒子,据此可以认为未知粒子是一种新原子态氢原子。  相似文献   

19.
A set of renormalization group recursion formulas which were proposed by Migdal are rederived, reinterpreted, and critically analyzed. The new derivation shows the connection between these formulas and previous work on renormalization via decimation and block transformations. The new interpretation which arises from these derivations indicates that Midgal's formulas are best understood as referring to systems in which the couplings are anisotropic. A strong indication of the correctness of this reinterpretation comes from the two-dimensional Ising model: The new interpretation gives an exact (!) expression for the critical couplings in this case for all ratios of Jx to Jy. This paper describes the major failings of this approximation which arise from its source as a decimation approximation, in terms of the well-known inadequacy of the fixed points which result from this type of scheme. Some proposals for improvement of the approximation are described. Finally, a new potential-moving scheme is proposed which is used to show that the Migdal approximation is exact when the potentials are strong and ferromagnetic in sign.  相似文献   

20.
A new automated Detection And Stimulation Head (DASH) has been developed for the Risø TL/OSL luminescence reader to provide easy access to new technologies, new signals and new measurement methods. The automated DASH includes a filter changer and a detector changer that makes it possible to change stimulation filters (4 × 4 filter combinations possible) and detectors (3 detectors possible) as part of a measurements sequence. The new automated DASH with dedicated driver electronics does not affect the use of other attachments, and can be retrospectively fitted to existing Risø TL/OSL readers.  相似文献   

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