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Summary The mass spectra of secondary ions emitted from PVK thin layers under 2 keV Xe+ bombardment were measured. The charasteristic elemental and molecular ions emitted were specified. The temperature dependence of the secondary emission was also measured. The results obtained were briefly discussed in terms of the ion beam-induced polymer structure fragmentation.Work supported by the research programme MR-I-5-8. 相似文献
3.
Keith S. Matlack Tomasz Labuda 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(1):91-93
A method for analyzing the fluorine content of glass using a microwave oven to digest the glass is presented. Analysis time and secondary waste generation are reduced using this method, without sacrificing accuracy. 相似文献
4.
Ferdinand P. Ferragu O. Lechien J.L. Lescop B. Magne S. Marty V. Rougeault S. Kotrotsios G. Neuman V. Depeursinge Y. Michel J.B. Van Uffelen M. Varelas D. Berthou H. Pierre G. Renouf C. Jarret B. Verbandt Y. Stevens W. Voet M.R.H. Toscano D. 《Lightwave Technology, Journal of》1995,13(7):1303-1313
Recent developments of stability control in mines, essentially based on Ge-doped fiber Bragg gratings (FBG) are reported including results about the different aspects of the system: accurate characterizations of FBG, sensor network topology and multiplexing method, user interface design and sensor packaging 相似文献
5.
Agnieszka J Klemm Piotr Klemm Kazimierz Rozniakowski Tomasz W Wojtatowicz 《Building and Environment》2002,37(12):1221-1232
This paper present the results of the investigation into a potential application of laser radiation for the detection of phase transition processes occurring on the surface layers of porous materials. An attempt was made to discuss in the approximation equations, the relationships between coefficients of the reflected light, the temperature and humidity of the surrounding environment. Laser light reflected from the porous surface carries information about the roughness of the structure. The presence of water microdrop on the surface of the porous material, as a result of condensation and thus a phase transition, leads to the phase displacement of individual rays, which is represented by different images. Therefore, a comprehensive analysis of the reflected light parameters allows a dynamic study of the phase transition phenomena without mechanical intervention. 相似文献
6.
DavidKatz TomaszLukasiak RickGentile 《世界电子元器件》2003,(6):27-30
如今的数字信号处理器(DSP)在性能、外围设备集成、功耗和成本方面都具备很多优势,很多系统设计人员希望在原有系统设计中利用DSP获得比传统处理器更好的效益。但其中一个 相似文献
7.
A. Cazarr F. Lpinois A. Marty S. Pinel J. Tasselli J. P. Bailb J. R. Morante F. Murray 《Microelectronics Reliability》2003,43(1):111-115
The aim of this paper is to analyze the feasibility of ultrathin packages through the electrical qualification of the technological process used, i.e. mechanical lapping. It considers polysilicon bipolar transistors which thickness can reach values lower than 10 μm. Forward mode and reverse mode characterizations show no significant degradation of pertinent characteristics, thus allowing to find applications in new compact packaging concept. 相似文献
8.
The role of silicon dioxide layers in microelectronics and the importance of their integrity are undisputable. From passivating coatings and masking layers for diffusion to ultra-thin tunneling films — all the silicon technology could not exist without silicon dioxide. This review deals with some aspects of the integrity of thin silicon dioxide films for VLSI applications. The problems of dielectric strength and wear-out are considered from the point of view of their mechanisms, models, oxide processing dependence, testing, and measuring. A brief presentation of statistical approaches commonly applied to reliability topics is also included. 相似文献
9.
Bronisław Jańczuk Tomasz Białopiotrowicz Emil Chibowski Andrzej Dawidowicz Anna Kliszcz 《Journal of Materials Science》1990,25(3):1682-1685
The contact angles of water drops and diiodomethane drops on pellets made of controlled porosity glasses have been measured. The surface of the glasses was modified by thermal treatment at 873 K which led to an increase in the surface concentration of boron atoms. Glass modified with Carbowax 20M (polyethylene glycol) and fully hydroxylated glass have also been studied. Using the measured contact angles and modified Young equation, the dispersion and nondispersion components of the glass surface free energy have been calculated. The values show that with increasing heating time (increasing surface density of boron atoms) an increase in the surface polarity takes place. However, the polarity of the same samples decreases after treatment with Carbowax, increasingly so with higher boron atom concentrations. 相似文献
10.