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1.
Abstract

The use of high pressure in food processing was recently developed in Japan. An historical presentation of such an application during the XXth century will be described. An analysis of the different possible actions of high pressure on living systems will be then given. Some results recently obtained in Bordeaux will also be discussed.  相似文献   

2.
Optical fiber sensing technologies are expected to apply for many future electronic control systems in automobiles, because of their inherent outstanding features, such as high noise immunity, high heat resistance, and flexible light propagation paths which can be applied to measure the movements and directions of the mobiles. In this paper, two typical applications of fiber sensing technologies in automobiles are described in detail. The combustion flame detector is one of the typical applications of a fiber spectroscopic technology which utilizes the feature of high noise and heat resistibility and remote sensibility. Measurement of engine combustion conditions, such as the detonation, the combustion initiation, and the air-fuel ratio, have been demonstrated in an experimental fiber sensing method. Fiber interferometers, such as a fiber gyroscope, have great possibilities in future mobile applications because they are applicable to many kinds of measurements for movements and physical variables. An optical fiber gyroscope utilizing the single polarized optical fiber and other optical devices has been developed. Quite an accurate measurement of vehicle position was displayed on a prototype navigation system which installed the fiber gyroscope as a rotational speed sensor.  相似文献   

3.
Optical fiber sensing technologies are expected to apply for many future electronic control systems in automobiles, because of their inherent outstanding features, such as high noise immunity, high heat resistance, and flexible light propagation paths which can be applied to measure the movements and directions of the mobiles. In this paper, two typical applications of fiber sensing technologies in automobiles are described in detail. The combustion flame detector is one of the typical applications of a fiber spectroscopic technology which utilizes the feature of high noise and heat resistibility and remote sensibility. Measurement of engine combustion conditions, such as the detonation, the combustion initiation, and the air-fuel ratio, have been demonstrated in an experimental fiber sensing method. Fiber interferometers, such as a fiber gyroscope, have great possibilities in future mobile applications because they are applicable to many kinds of measurements for movements and physical variables. An optical fiber gyroscope utilizing the single polarized optical fiber and other optical devices has been developed. Quite an accurate measurement of vehicle position was displayed on a prototype navigation system which installed the fiber gyroscope as a rotational speed sensor.  相似文献   

4.
Recent experiments covering a range of problems including the nuclear hyperfine structure of bond-centered muonium in diamond and GaP, charge-cycling reactions of muonium in Si at high temperatures, muonium state dynamics in Si probed by RF-SR, and endohedral muonium in semiconducting C60 compounds, are discussed. These examples show that as traditionalSR techniques are continually being refined and new methods are being developed,SR is becoming an increasingly powerful tool to investigate the behavior of muonium and the in many respects analogous, and technologically relevant, hydrogen centers in semiconductors.  相似文献   

5.
We report studies of examples of reflection-asymmetric nuclei which are difficult to access using compound nucleus reactions. The octupole radium isotopes withN>132 and radon isotopes are not accessible by reactions employing stable targets and beams; we have shown that multinucleon transfer reactions can populate these nuclei with sufficient yield for their structure to be determined. We report high-spin studies in218, 220, 222Rn and222, 224, 226, 228, 230Ra: these show that the Ra isotopes withA<228 have the characteristics of octupole deformed nuclei whereas the Rn isotopes behave like octupole vibrators. Measurements of theB(E1)/B(E2) ratios indicate that the electric dipole moment in these nuclei is constant with spin. The most octupole deformed nuclei are predicted to be uranium isotopes withN≈132; measurements of the very fissile nucleus226U suggest that it is octupole deformed and has a large intrinsic electric dipole moment. Finally, we speculate that the best examples of pear shapes are the hyperdeformed minima predicted to lie low in uranium isotopes withN≈140; their signature of high-multiplicity low-energyE1 photon cascades should be detectable using present-day high-efficiency germanium arrays.  相似文献   

6.
Laser-diode (LD) interferometry based on heterodyne techniques is described. The developments covered include: sinusoidal phase- modulating, distance-measuring feedback and phase-shifting interferometry. The wavelength is controlled by the laser injection current and is continuously or stepwise changed to introduce a time-varying phase difference between the two beams of an interferometer with unbalanced optical path lengths. A feedback interferometer is described with electronics to stabilize the phase shift and to lock the interferometer on a preset phase condition by controlling the injection current of the LD. An automated phase-measuring interferometric system is developed in which the laser current is changed to synchronize intensity data acquisition with the clocks of a charge-coupled device. A typical experimental result shows measurements of the profile of a diamond- turned Al surface.  相似文献   

7.
Apoorva Patel 《Pramana》1993,41(1):139-165
I review the current status of several lattice QCD results. I concentrate on new analytical developments and on numerical results relevant to phenomenology.  相似文献   

8.
We give a review of Boson expansion methods applied in the quantum theory as e.g. expansions of spin, bifermion and Fermion operators in cases of the finite and infinite number of degrees of freedom. The basic purpose of the paper is to formulate the most general criterions allowing to get so called finite spin approximation of any given Bose field theory, and the class of Fermion theories associated with it. Quite the converse, we need also to be able to reconstruct the primary Bose field theory while any finite spin or Fermi systems are given.  相似文献   

9.
Recent developments in the techniques of generation and measurement of picosecond and sub-picosecond pulses from mode-locked lasers are reviewed. Particular attention is paid to frequency tunable, bandwidth-limited pulses from dye lasers, especially the cw dye laser. In measurement the main emphasis is put on the rapid advances of the last few years in ultra-fast streak-cameras, ans the recent developments in streak-camera synchronization to a cw mode-locked laser is described. Future prospects for shorter wavelenght pulses in the uv and vuv are briefly considered.  相似文献   

10.
This article provides a concise overview of recent theoretical results concerning the theory of vortons, which are defined to be (centrifugally supported) equilibrium configurations of (current-carrying) cosmic string loops. Following a presentation of the results of work on the dynamical evolution of small circular string loops, whose minimum energy states are the simplest examples of vortons, recent order-of-magnitude estimates of the cosmological density of vortons produced in various kinds of theoretical scenarios are briefly summarized.  相似文献   

11.
Recent developments in arc spraying   总被引:1,自引:0,他引:1  
New trends in arc-spraying processes and materials are reviewed. The wide field of applications for arc-sprayed coatings is demonstrated and discussed. Coating systems against corrosion, against wear, and for special applications (e.g. coatings for casting molds or biocompatible layers on artificial implants) are described. New process variants, e.g. spraying with a controlled-wire feed system, use of a pulse power source, or vacuum-arc spraying with one or two wires, are expected to appear with further commercial applications of these techniques  相似文献   

12.
13.
《Physics Reports》1998,306(3):109-211
In this review we present a pedagogical introduction to recent, more mathematical developments in the Skyrme model. Our aim is to render these advances accessible to mainstream nuclear and particle physicists. We start with the static sector and elaborate on geometrical aspects of the definition of the model. Then we review the instanton method which yields an analytical approximation to the minimum energy configuration in any sector of fixed baryon number, as well as an approximation to the surfaces which join together all the low energy critical points. We present some explicit results for B=2. We then describe the work done on the multibaryon minima using rational maps, on the topology of the configuration space and the possible implications of Morse theory. Next we turn to recent work on the dynamics of Skyrmions. We focus exclusively on the low energy interaction, specifically the gradient flow method put forward by Manton. We illustrate the method with some expository toy models. We end this review with a presentation of our own work on the semi-classical quantization of nucleon states and low energy nucleon–nucleon scattering.  相似文献   

14.
There has been consistent drive towards research and innovation in oil production technologies in order to achieve improved effectiveness and efficiency in their operation. This drive has resulted in breakthrough in technologies such as the application of ultrasound (US) in demulsification and enhanced oil recovery (EOR), and usage of high-volume hydraulic fracturing and special horizontal well for shale oil and gas extraction. These can be observed in the increment in the number of commercial oil technologies such as EOR projects that rose from 237 in 1996 to 375 in 2017. This sustained expansion in EOR resulted in their total oil production rising from 1.5 million barrels per day in 2005 to 2.3 million barrels per day in 2020. And this is predicted to increase to about 4.7 million barrels per day in 2040, which represent about 4% of total production. Consequently, in this review, the developments in the utilization of US either as standalone or integrated with other technologies in EOR and dehydration of water in oil emulsions were analyzed. The studies include the optimization of fluid and US properties in EOR and demulsification. Reports on the treatment of formation damage resulting from inorganic salts, organic scales, drilling fluid plugs, condensate, paraffin wax and colloidal particle with US-assisted EOR were also highlighted. Moreover, the mechanisms were examined in order to gain insightful understanding and to aid research investigations in these areas. Technologies such as US assisted green demulsification, high intensity focused ultrasound, and potential pathways in field studies were assessed for their feasibilities. It is essential to evaluate these technologies due to the significant accrued benefits in them. The usage of green demulsifiers such as deep eutectic solvents, ionic liquids and bio-demulsifiers has promising future outlook and US could enhance their technical advancement. HiFU has been applied successfully in clinical research and developments in this area can potentiality improve demulsification and interfacial studies (fluid–fluid and solid–fluid interactions). As regards field studies, there is need to increase actual well investigations because present reports have few on-site measurements with most studies being in laboratory scale. Furthermore, there is need for more detailed modeling of these technologies as it would assist in conserving resources, saving research time and fast-tracking oil production. Additional evaluative studies of conditions such as the usage of Raschig rings, crude oil salinity and high temperature which have improved demulsification of crude oil emulsions should be pursued.  相似文献   

15.
Summary A brief review is given of the present state of the art in the theory and numerical simulation of ionic melts, and in particular of molten alkali halides. Some recent developments concerning the theoretical evaluation of the static pair structure, the phase diagram and the microscopic dynamics in these melts are discussed. The importance of ionic polarizabilities is stressed. Some perspectives for future work are pointed out in the conclusion. Unité de Recherche Associée 1325 du CNRS.  相似文献   

16.
17.
彭英杰  刘之景  刘磁辉 《物理》2003,32(9):599-603
随着人类基因组测序的完成和蛋白组学工程的开展,具有高产出测序的特性的DNA微阵列技术的发展日新月异,其应用已经深入到了生命科学研究的很多方面.与此同时,几种新的DNA微阵列制备技术迅速发展起来,文章介绍了滚轮放大技术、聚酰胺胺表面法、三甲氧基对胺苯基硅烷/重氮化法、化学纳米印迹法等四种制备方法的新进展。  相似文献   

18.
19.
20.
Chemical processing with lasers: Recent developments   总被引:1,自引:0,他引:1  
Chemical processing of materials with lasers is a new and interdisciplinary field with many already realized and potential applications in different areas of technology. This overview summarizes some recent developments in this rapidly expanding field.  相似文献   

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