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1.
M. Malinowski R. Wolski Z. Frukacz T. Lukasiewicz Z. Luczynski 《Journal of Applied Spectroscopy》1995,62(5):840-843
Optical properties of the Sm3+ ion in YAG crystals have been investigated, in particular:
The relatively large emission cross section and long fluorescence lifetime enable red laser action to be obtained. 相似文献
| – | - the energy level diagram of Sm:YAG has been established. |
| – | - the emission characteristics of the metastable state4G5/2 have been determined. |
| – | - the oscillator strengths of various Sm transitions have been investigated using the Judd-Ofelt theory. |
2.
A. Benninghoven D. Jaspers W. Sichtermann 《Applied Physics A: Materials Science & Processing》1976,11(1):35-39
Secondary-ion mass spectroscopy (SIMS) is a hydrogen, isotope and compound sensitive analytical technique of extremely high
absolute sensitivity. Continuing earlier measurements for carboxylic acids, adsorbed alcohols etc., we have carried out a
systematical investigation of secondary-ion emission from metal-supported amino acids, containing various functional groups
(e.g., alanine, phenylalanine, cysteine, arginine). In order to avoid damage effects we applied extremely small primary-ion
current densities in the 10−9 A·cm−2 range.
The main results of our investigations can be summarized as follows:
相似文献
| – | - All investigated amino acids produce high-intensity secondary-ion parent peaks (M+1)+ and (M−1)−. |
| – | - In addition positive as well as negative fragment ions representative for the different functional groups are emitted with high yields. |
| – | - For 2.5 keV Ar+-ions the absolute yields for the parent ions and the most important fragment ions are in the range of 0.1; the damage cross section is >10−14 cm2 for all investigated acids. The resulting absolute sensitivities are below 10−6 of one monomolecular layer or <10−12 g. |
3.
Francesco Caravenna Giambattista Giacomin Massimiliano Gubinelli 《Journal of statistical physics》2006,122(4):799-832
We consider a model of a random copolymer at a selective interface which undergoes a localization/delocalization transition. In spite of the several rigorous results available for this model,
the theoretical characterization of the phase transition has remained elusive and there is still no agreement about several
important issues, for example the behavior of the polymer near the phase transition line. From a rigorous viewpoint non coinciding
upper and lower bounds on the critical line are known.
In this paper we combine numerical computations with rigorous arguments to get to a better understanding of the phase diagram.
Our main results include:
2000 MSC: 60K37, 82B44, 82B80 相似文献
| – | Various numerical observations that suggest that the critical line lies strictly in between the two bounds. |
| – | A rigorous statistical test based on concentration inequalities and super–additivity, for determining whether a given point of the phase diagram is in the localized phase. This is applied in particular to show that, with a very low level of error, the lower bound does not coincide with the critical line. |
| – | An analysis of the precise asymptotic behavior of the partition function in the delocalized phase, with particular attention to the effect of rare atypical stretches in the disorder sequence and on whether or not in the delocalized regime the polymer path has a Brownian scaling. |
| – | A new proof of the lower bound on the critical line. This proof relies on a characterization of the localized regime which is more appealing for interpreting the numerical data. |
4.
Xiang-wen Chen Hui-zhen Li Gui-qing Li Ling Qin Zhi-fang Zhang 《International Journal of Infrared and Millimeter Waves》1994,15(9):1555-1566
This paper presents a theoretical method for design quasi-optics power combiner of solid-state millimeter — wave sources, and gives theory analysis to some problem concerned. Here is the structure:
相似文献
| 1. | Epitome of microwave power combiner. |
| 2. | Gauss light beam and the field distribution in the resonator. |
| 3. | The design of the resonator |
| (1) | Confocal resonator |
| (2) | Objective function |
| (3) | The global optimization method and the program flow chart. |
| 4. | Example |
| 5. | Reference |
5.
| 1. | The intensities of hypersensitive transitions at 293 K increase with decreasing Ln−O bond length in both praseodymium and europium complexes. The intensity increase can also be caused, for praseodymium crystals, by lower energy of f-d transition bands. |
| 2. | The temperature dependence of the3H4→3Po transition for Pr(CF3COO)3·3H2O crystal probably indicates a phase transformation occurring at about 50 K. |
| 3. | The electronic lines are accompanied be weak vibronic components for transitions that obey the selection rules †J=0,2. |
| 4. | The intensities of vibronic sidebands in excitation spectra are stronger than those in emission ones for europium single crystals at 77 K. |
| 5. | Lowering of the energy of f-d bands is observed in the crystals in the order Pr(CCl3COO)3<Pr(CF3COO)3, what can affect the vibronic coupling more strongly in the former case. |
| 6. | The relative-intensity relation for the two types of europium crystal (I and II) indicate stronger distortion of coordination polyhedra in trifluoroacetate crystals. |
| 7. | The number of components of the5Do→7FJ transition indicates the existence of two symmetry centers of the Eu3+ ion in trichloroacetate, thus confirming results obtained by the X-ray method. |
6.
Our results lead to the following conclusions.
The authors are grateful to O. Ipat’eva, A. Kokh, and A. Yurkin of the “Single-Crystal” Collective Technica Institute for
supplying the high-quality high-voltage equipment elements. 相似文献
| 1. | A CVL with a nonlinear frequency converter can be regarded as a source of high-power UV radiation discretel tunable in three wavelengths. |
| 2. | The presence of the CVL beam of a low-coherence (single-pass) radiation is one of the main factors that limi the efficiency of the nonlinear conversion. |
7.
B. Gikal S. Dmitriev P. Apel S. Bogomolov O. Borisov V. Buzmakov G. Gulbekyan I. Ivanenko O. Ivanov M. Itkis N. Kazarinov I. Kalagin I. Kolesov A. Papash S. Paschenko A. Tikhomirov M. Khabarov 《Physics of Particles and Nuclei Letters》2008,5(7):642-644
The construction of the DC-60 Heavy Ion Cyclotron for the Interdisciplinary Scientific Research Complex (ISRC) in Astana started
in early 2004. The cyclotron was manufactured and tested at the Flerov Laboratory of Nuclear Reactions (FLNR) in Dubna. The
main units were delivered to Astana and assembled in the ISRC building in the summer of 2006. The cyclotron was turned on
in September, 2006. The first heavy ion beams in the whole A/Z and energy ranges were accelerated and extracted in December,
2006.
The complex, based on the DC-60 cyclotron, is intended for applied and fundamental research using accelerated heavy ion beams
ranging from Carbon to Xenon with energies in the range of 0.34–1.77 MeV/nucleon, as well as for experiments on the channel
of low energy ion beams, where the ion extraction voltage supplied by the ECR source reaches 25 kV. The energy variation of
the accelerated ions is accomplished by changing the ion charge. The possibility of smoothly tuning the ion energy by ±30%
of its nominal value can be seen by changing the cyclotron magnetic field. Within the framework of commissioning the DC-60
cyclotron, a number of experiments were carried out with accelerating charged particle beams in the main points of the working
diagram
The text was submitted by the authors in English. 相似文献
| • | The acceleration modes for Nitrogen, Argon, and Krypton (14N2+, 40Ar4+, 40Ar5+, 40Ar7+, 84Kr12+) ions on the 4th and 6th harmonics of RF accelerating voltage in the whole range of magnetic field variation were investigated. |
| • | A Krypton accelerated ion beam (84Kr12+) with a current of up to 2 μA was extracted into the beam transport channel, matched, and transported to a technological facility for polymer film irradiation. An irradiation field with the required particle flux density and homogeneity was provided by 2 scanner magnets, and the experimental irradiation of polymer films was carried out. |
| • | The operational modes, with magnetic fields corrected by radial correcting coils of cyclotron, were investigated. |
8.
A. Kozanecki 《Journal of Applied Spectroscopy》1995,62(4):731-741
RBS/channeling investigations of Yb-, Nd-, and Er-doped III–V compounds and silicon revealed some regularities in the behavior
of RE atoms:
Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warshawa, Poland. Published in Zhurnal Prikladnoi
Spektroskopii, Vol. 62, No. 5, pp. 145–157, July–August, 1995. 相似文献
| 1. | Nonsubstitutional location of RE atoms seems to be a common rule in zincblende structure semiconductors. An exception is the case of Yb in InP and InP-based compounds. |
| 2. | Recrystallization of the layers amorphized by implantation of RE ions at room temperature is never complete, due to the presence of RE atoms in the layers. The implanted RE atoms segregate at the surface during thermal annealing. Implantation at elevated temperatures prevents amorphization and out-diffusion of REs. |
| 3. | Nonsubstitutional locaton of Er in silicon has been well documented here by measurements of RBS/channeling spectra (Figs. 9a and 9b) and angular scan profiles as well (Figs. 11a and 11b). Careful consideration of all the experimental data allows us to conclude that the implanted Er atoms locate close to hexagonal interstitial lattice sites. This tentative conclusion will be tested in the near future by model simulations. |
9.
M. V. Gorbatenko 《General Relativity and Gravitation》2005,37(1):81-98
New possibilities in the solution to the general relativity problems appearing in the conformally invariant generalization of Einsteins equations are addressed. The conformally invariant equations and their solutions possess the following properties:
The paper briefly describes these properties and discusses possible methods to use them for the solution of general relativity problems. 相似文献
| 1. | The Cauchy problem is posed without any constraints on the Cauchy data. |
| 2. | Solutions with discontinuities on space-like hypersurfaces are admitted. |
| 3. | A conserved current vector appears. |
| 4. | A new function of state similar to entropy appears. |
| 5. | The gauge vector and the lambda term can be interpreted in terms of degrees of freedom of 1/2-spin particles. |
10.
The influence of the frequency f of applied ac electric field on the time dependence of electric field induced deformations
of homeotropic nematic layers is studied numerically. Three kinds of nematic liquid crystals were considered:
| – |
non-flexoelectric nematic with negative dielectric anisotropy, Δɛ < 0 相似文献
11.
12.
The seminal paper by Ya. B. Zeldovich (Soviet Physics Uspekhi 11, 381–393, 1968) is reprinted here, together with an editorial comment on its lasting scientific relevance, and a biography
of the author.
13.
From our experiments the following conclusions follow:
14.
Luiz C. L. Botelho 《International Journal of Theoretical Physics》2009,48(6):1701-1711
In this paper we intend to present some path-integral studies in the problem of confinement in the presence of fermionic and
scalar magnetic monopole fields through:
15.
Wagendristel A. Tschegg E. Semerad E. Bangert H. 《Applied Physics A: Materials Science & Processing》1976,10(3):237-243
Computer simulation of superimposed lattice, grain boundary and surface diffusion, characteristic for polycrystalline thin
film diffusion systems, was performed by way of discretisation of the nonlinear diffusion law. In order to give a vivid impression
how such a complex process takes place under some typical conditions we have chosen pseudo three-dimensional computer plots
of the spacial distribution of the concentration instead of the commonly used iso-concentration diagrams. The following cases
are considered:
16.
Frank K. Tittel 《Applied physics. B, Lasers and optics》1998,67(3):273-273
This special issue of Applied Physics B – Lasers and Optics attempts to document the current status and trends of environmental trace gas detection through a collection of 32 invited papers motivated in part by the need for and importance of a detailed understanding of our environment. Although numerous traditional optical methods, gas chromatography, and mass spectrometry have served us extremely well in atmospheric and environmental trace gas detection, promising new sensing and precise measurement techniques based on laser spectroscopy have emerged and been successfully used in numerous applications. The concept and timing of this special issue has been stimulated to some extent by recent exciting developments of several novel technologies, such as diode and fiber lasers for the optical communications industry, diode-pumped solid-state lasers, and novel bulk and waveguide infrared nonlinear materials. These can be applied to the ultra-sensitive, highly selective detection and real-time analysis of a large number of trace gas species by means of absorption spectroscopy in the mid-infrared fingerprint region, which contains virtually all the fundamental vibrational modes of molecules. Reduction of cost and complexity makes such spectroscopic sources more universally available and user friendly to both established and new fields that include air quality, atmospheric chemistry, industrial, traffic, and rural emissions, chemical analysis and process control, and medical applications.This issue, consisting of two parts, chronicles some of the most significant and representative current research trends. It is hoped that this issue will inspire new directions to both specialists and newcomers in which to drive this exciting field and envision future applications of environmental sensing.Part I: Spectroscopic air monitoring techniques and instrumentation
17.
We have developed a sequential radiochemical separation method (SRCS) in order to isolate each trans-uranium element (TRU)
contained in a TRU target (or fuel) irradiated in the experimental fast reactor JOYO.
The chemical separation procedures for SRCS consist of the following steps:
18.
After over 20 years of development, noise mapping software is, today, a professional tool that is widely used by many people with different backgrounds and experience in the applications, the data and the software used. The user has the possibility to influence the quality of the result of the noise mapping process. The major factors affecting good practice include:
19.
E. Bodenstedt 《Hyperfine Interactions》1976,2(1):1-14
In this talk the discussion of nuclear physics studied by hyperfine methods is limited to a few topics of high actuality:
20.
ForG a classical group, an equivalence is exhibited between:
|