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971.
S V Moharil  B T Deshmukh 《Pramana》1976,6(3):183-187
A comparative study ofγ-ray colouration and electrodeless discharge excitation is reported for NaF. New absorption bands and glow peaks were found. These are shown to be characteristic of electrodeless discharge method of colouration. These are attributed to the multiple types of defects. Further, it is shown that the process by which such defects are formed is strongly temperature dependant. A tentative explanation for the peculiar characteristic of the electrodeless discharge excitation is put forth. The possibility of exploiting these peculiarities for the study of certain properties of colour centres is pointed out.  相似文献   
972.
Fine powder of KI was coloured in an electrodeless discharge. Due to quick bleaching of the F centres produced in this method, it was possible to prepare the samples that were almost free from the F centres. High concentration of the electron deficient centres could be produced, which were studied by measuring the diffused reflectance. A band at 354 nm is shown to be composed of two overlapping bands. Further, growth of a band appearing at 265 nm is studied. Bleaching characteristics of the samples are studied and it is shown that, similar to F centre bleaching, bleaching of these samples also proceeds in at least two steps. The difference between two components of the bleaching curves is quite marked. Further it is showed that the components are related to the presence of different absorption bands and appear at different stages of colouration.  相似文献   
973.
974.
本文分析了原真空获得与测量实验装置结构上的不足之处.介绍了对原装置所进行的改进工作──主要用于取代感应圈的专用电源的制作。  相似文献   
975.
空间衍射声波波前与压力场的计算机层析三维重建   总被引:2,自引:0,他引:2  
李喜德 Sched.  S 《光学学报》1998,18(12):669-1675
应用脉冲载波电子散斑干涉(pulsedcarried-ESPI)与计算机层析技术(CT),实现了由高压电极放电激励所产生的瞬态传输声场在经过不同孔径模板衍射后波前与压力场的三维重建,给出了数值结果,并对噪声条件下的计算机层析重建进行了讨论。  相似文献   
976.
977.
A peripheral neuropathy with hyperalgesia and allodynia was produced by loosely tying constrictive ligature around the left sciatic nerve of rats, i.v. injection of anisodamine 20mg/Kg abolished both neuropathic hyperalgesia responses to noxious radiant heat and ectopic discharges generated from the injured region of the nerve. Anisodanime applied either systemically or locally to the damaged area of the nerve not only ceased the spontaneous ectopic discharges recorded from A_β to C fibers but also blocked the afferent ectopic discharge elicited by K~+ channel blocker, noradrenaline, Ca~(2+) or antidromic stimulation of sciatic nerve proximal to the injured nerve area. The experiments indicated that anisodamine probably possessed a calcium channel blocker-like activity and produced selective block of the new channels in the injured area. It is suggested that anisodamine may be a candidate therapeutic agent in relieving hyperalgesia and allodynia following nerve injury.  相似文献   
978.
979.
We prove some preservation theorems concerning inductive and model‐complete theories in the framework of semi‐classical logic introduced in [1]. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
980.
Self‐consistent two‐dimensional (2D) simulations of short‐pulsed dielectric barrier discharge (DBD) in pure xenon have been performed. It is shown that during short current pulse the traversal inhomogeneity of the plasma parameters can be important only at the end of the current pulse as an edge effect close to the side walls. During the current pulse, the gap voltage drops until the ionization wave reaches the cathode so the current in the cathode sheath is the displacement current. This means that almost all of the absorbed power is deposited into excitation of xenon atoms and not to the ion heating in the cathode sheath as in the traditional glow discharges. This fact is one of the reasons of high efficiency of short‐pulsed DBD. The developed model allows one to estimate the temporal position of the plasma‐sheath boundary. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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