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1.
CW operation of a RbCl:Li-FA(II) laser has been obtained under pumping by a red laser diode. Pump power at threshold is 90 mW. Single frequency operation of the color center laser has been achieved. The intensity noise generated by two pump sources (laser diode and Kr-ion laser) is compared  相似文献   
2.
It is experimentally demonstrated that a tenfold decrease in the level of spurious polarization modulation can be achieved in a fiber optic phase modulator comprising two fiber sections featuring the polarization mode conversion, arranged on the same piezoelement.  相似文献   
3.
The VÉPP-5 injection complex under construction at the Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences is a powerful source of intense electron and positron bunches at 510 MeV, which covers all needs of the electron–positron colliding beam setups currently operating and under construction at the Institute of Nuclear Physics. The complex includes a 285 MeV linear electron accelerator, a 510 MeV linear positron accelerator, and an accumulator–cooler with beam injection and ejection channels. Intense work on the design, assembly, and tuning of the linear electron accelerator has been conducted in the last 2 yr. As a result, by August 2002 the linear electron accelerator was put into operation with all standard subsystems. By this time, the isochronous achromatic turning of the electron beam, a system for converting electrons into positrons, and the first accelerating structure of the linear positron accelerator were assembled and put into operation. All this made it possible to accelerate the positron beam up to 75 MeV. Preliminary results of tests of the linear accelerators are presented.  相似文献   
4.
We describe the first chlorine-free synthesis of nanozirconooligocarbosilanes through thermal cocondensation of low-molecular oligocarbosilanes and zirconium tetrakis(diethylamide). The starting reagents, reaction intermediates, and final products have been characterized by 1H, 13C, and 29Si nuclear magnetic resonance, UV and IR spectroscopy, gel-permeation chromatography, thermogravimetry, transmission electron microscopy (TEM), and elemental analysis. The synthesized nanozirconooligocarbosilanes have been used to fabricate ceramic fibers and matrices through thermal and chemical processing. TEM results demonstrate that the particles of zirconium and products of its reactions with silicon, carbon, and nitrogen range in size from 10 to 20 nm in the oligomers and from 20 to 30 nm in the ceramics.  相似文献   
5.
Cobalt-containing nanoparticles have been prepared via thermal decomposition of cobalt acetate on the surface of poly(tetrafluoroethylene) (PTFE) microgranules forming a fluidized bed over the surface of hot mineral oil. Using transmission electron microscopy, the average size of the cobalt-containing nanoparticles has been determined to be 3.6 nm. The composition and structure of the nanoparticles have been determined by x-ray diffraction, extended x-ray absorption fine structure spectroscopy, and electron paramagnetic resonance, and the magnetic properties of the synthesized nanomaterial have been studied. The results indicate that the nanoparticles have a core-shell structure, with a metallic cobalt core (?10 vol%) and a shell consisting of three phases: Co3O4 (?80%) and small amounts of CoO and CoF2 (?10%). The fluoride phase results from the interaction of the nanoparticles with surface fluorine atoms of the PTFE microgranules.  相似文献   
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A measuring device is developed to replace devices used previously in order to more accurately measure the length of a bolt of cloth being woven on a loom. Knowing the actual weft density of the cloth, it is possible to reliably measure the length of the bolt by determining the number of weft threads in it. The measurement error in tests performed on STB-type looms is no greater than ±0.03-0.05 m for bolts up to 50 m in length.  相似文献   
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A. V. Gubin 《Metallurgist》1999,43(5):199-199

Jubilees

The Sinarskii Pipe Plant  相似文献   
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