流体物理研究所的高速光学技术

本文阐述了高速摄影技术、光谱测温、激光干涉测速和脉冲 X射线摄影的实时光电记录等光学测试技术在中物院流体物理研究所的发展和应用现状。被研究的测试对象均是瞬时高速过程 ,具有时空分辨的要求 ,其时间分辨本领在 ms至 ns范围内     

Photographic Emulsion Grains with Cores: Part I. Evidence for the Presence of Cores*

Neutral iodobromide emulsions made by the addition of silver nitrate to alkali halides in gelatin may, under certain conditions, contain a proportion of grains with cores of iodobromide phases. The maximum iodide contents (i) of these cores are related to the precipitation temperature (T) by the empirical equation i= 34.5+0.165(T–25). Grains containing such cores show very regular print-out distribution.     

The Reliability of Bleaching Techniques for the Determination of Latent Image Distribution in Silver Bromide and Iodobromide Emulsions*

The reliability of various bleaching Techniques was studied on the basis that a bleach should destroy surface latent image compleldy and that the internal speed should be independent of the precise bleaching conditions ond be as high as possible. Only two treatments satisfied these conditions. These were a potassium-ferricyanide-phenosafranine bleach and a silver-dichramale bleach ofter a washing treatment.     

40 Years of the All-Russia Scientific-Research Institute for Physical Optics Measurements

An analysis is presented of the activities of the All-Russia Scientific-Research Institute for Physical Optics Measurements in the area of setting up and upgrading the system for unifying measurements in optical radiometry, which have been obtained in the 40 years of the existence of the Institute. Development lines for this area of measurement are considered in relation to the latest 21st century technologies. __________ Translated from Izmeritel'naya Tekhnika, No. 11, pp. 3–7, November, 2005.     

Calibration of X-Ray Film Used in the Detection of Soft X-Rays from the CTR Device Sceptre

To assist in the interpretation of X-ray pinhole photographs in thermonuclear research with the toroidal pinch device Sceptre, with a view to applying such photographs to the study of the energy spectrum of the electron flux incident upon the torus walls (constructed from aluminium and copper), experiments have been performed to determine the photographic effect of the X-rays produced from a known flux of electrons of given energy. A demountable X-ray tube was made in which the target was alternately copper or aluminium foil, indirectly heated, and in which a beam of electrons of known energy was focused on the foil. X-rays from the target fell upon llford Industrial G type X-ray flim, after passing through one or more metal foils. By maintaining a known beam current for different times, a range of exposures was given to different parts of the same film specimen and density-log exposure curves were compiled. Results of such experiments are presented for target elements of aluminium and copper and various thicknesses of absorbing foil, for electron energies in the range 1.8-8.4 KeV. A method is suggested by which data accumulated in this way may be used in analysis of electron energy spectra.     

News from the Royal Society of Chemistry's Annual Meeting: Folate assay fails

David Bradley reports from Edinburgh (U.K.).     

Development of superconducting and cryogenic technology in the Institute for Technical Physics (ITP) of the Research Center Karlsruhe

Since the early 1970s the Institute for Technical Physics of the Research Center Karlsruhe has been involved in the development of superconductivity for research and industrial applications. A broad program with a focus on the superconducting magnet technology was established to include large magnets for nuclear fusion, high-field magnets for nuclear magnetic resonance spectrometers, ore separation and energy storage magnets. Research and development work was performed in collaborative projects with other national as well as international institutions and industry. The success of these projects has been supported by a broad foundation of engineering science in superconductor development, electrical and cryogenic engineering. Several well known test facilities like TOSKA, STAR, HOMER, MTA along with well equipped laboratories for conductor development, materials at cryogenic temperatures, cryogenic high-voltage engineering have made substantial contributions to in-house, national and international projects. A strong cryogenic infrastructure with two refrigerators and sophisticated cooling circuits from about 4.5 K down to 1.8 K assure the reliable operation of these large facilities. Last but not least, cryogenic research, including vacuum pumps for International Thermonuclear Experimental Reactor, improvements in thermal insulation, cryogenic instrumentation and small on board refrigerators has supported progress in this field. High-temperature superconductivity projects for low AC loss conductors, a 70 kA current lead and a fault current limiter are currently in progress.     

Development of a process for treatment and solidification of liquid radioactive concentrates from the Leipunskii Institute of Energy Physics

Treatment of liquid radioactive concentrates (LRCs) from the Leipunskii Institute of Energy Physics using Termoksid-35 ferrocyanide sorbent was studied. After passing LRC with a volume activity of 3.9 × 10⁸ Bq l⁻¹ through a column packed with the sorbent, the volume activity of the filtrate does not exceed 3.7 × 10⁴ Bq l⁻¹. The LRC decontaminated from the major amount of radionuclides is fed to cementation. A formulation of a cement compound with a polyfunctional additive consisting of finely dispersed cement, bentonite clay, biocidal additive, plasticizer, and defoamer was developed. For the storage of a container filter with the spent ferrocyanide sorbent, it is suggested to place it in a 1 m³ metallic container in which the cement compound with the LRC decontaminated from the major fraction of cesium acts as biological protection. The γ-radiation dose rate from the 1 m³ container filled with the cement compound, with the filter with the spent sorbent placed inside, was calculated. A technology for processing of liquid radioactive concentrates from the Leipunskii Institute of Energy Physics was suggested and substantiated.     

The Extraction and Processing of Data from Bubble Chamber Photographs

If an ionizing particle passes through a super heated liquid boiling can take place on the ions created by the particle. These vapour bubbles are photographed under flash illumination and show up the track of the particle. By using two or more cameras the original space position of the track is calculated from measurements made on the different views. The present total rate of production of such photographs in the various high energy physics laboratories throughout the world is about ten million photographs per year. The various methods, in use today, for processing all this information are described and some comments made about possible future development.     

理化所三维金属纳米结构飞秒激光加工获重要进展

中科院理化技术研究所段宣明团队、日本理化学研究所河田聪团队通过合作,近日在利用飞秒激光多光子纳米加工技术进行三维微纳结构制备的研究中获得重要进展,成功突破了光学衍射极限,实现了纳米尺度的三维金属纳米结构加工.     

Behaviour of Thiosulphate in Electrodialysis in the Presence of Photographic Gelatin

Electrodialysis of a 10 per cent solution of gelatin containing 30 /M of thiosulphate labelled 3,S in the outer sulphur atom was carried out with a brentzinger apparatus. Forty-five per cent of the radioactivity appeared in the anodic liquid, thirty per cent in the cathodic and the remaining twenty-five per cent in the gelatin solution. The validity of these results is discussed also in relation to other experiments carried out with ,SS labelled sulphate and :aP labelled phosphate.     

The Adsorption of Gelatin to Developed Silver and the Role of Gelatin in Development

The adsorption of gelatin to developed silver is demonstrated and semi-log isotherms are constructed at two temperatures in the presence and absence of developer components. Analysis of the isotherms suggests that the adsorption is weak (physicol) but this is contradicted by its observed irreversibility. The induction period and apparent energy of activation of development in the liquid system studied are shown to increase with gelatin concentration.The effect of a cationic wetting agent on adsorption and development is described. The specific gravity of silver developed under various conditions is recorded.The possibility is suggested that the firmly bound layer of gelatin on emulsion groins, creates a "thermal" barrier as a result of a difference (not proven) in the heat of adsorptions to silver hol1de and silver. Loosely bound gelatin is believed to form a conventional negative charge barrier.     

The Influence of Heat on the Sensitivity of a Photographic Film to Low Intensity Light

A fast radiation monitoring film, the lIford PM I, was exposed at 0 per cent relative humidity to low intensity u-v light from a plastic scintillator, the exposure temperoture being varied between +10 and +75°C. Films were also heated at 60°C. and 0 per cent RH and subsequently exposed to the scintillator light at 30O°C, the results indicating the presence of latent sub-image in the heated film at the end of the heating. From the temperature dependence of the net film density obtained with constant heating time the activation energy of 126 eV was derived, this corresponding to the formation energy of a Frenkel defect in silver bromide. The results suggest that the effect of increased temperature in increasing light absorption is a minor one in this instance.