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21.
B. G. Goldenberg T. N. Goryachkovskaya V. S. Eliseev N. A. Kolchanov V. I. Kondrat’ev G. N. Kulipanov V. M. Popik S. E. Pel’tek E. V. Petrova V. F. Pindyurin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2008,2(4):637-640
Preliminary results of fabrication and testing of LIGA mask samples for deep x-ray lithography in the spectral range of 3.5–13.5 keV are presented. The mask fabrication method is based on direct mask patterning with minimum element sizes of ≥ 10 μm by a synchrotron radiation x-ray microbeam. Such a method does not require an intermediate mask, which significantly simplifies fabrication and reduces the laboriousness and cost of LIGA masks. 相似文献
22.
Glyavin M.Yu. Goldenberg A.L. Kuftin A.N. Lygin V.K. Postnikova A.S. Zapevalov V.E. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1999,27(2):474-483
In order to provide electron beams of powerful gyrotrons, magnetron-injection guns operating in the regime of the temperature limited current are used. The electron beam quality and gyrotron performances are defined both by the cathode emission processes and the processes occurring in the electron beam during its formation and transportation. The results of measurements of the energy spectrum and velocity spread of the gyrotron electron beam in different regimes are given. Experimental data on the parameter of efficient emission inhomogeneity for different regimes are presented, as well as the dependencies of electron beam parameters on efficient inhomogeneity of the cathode 相似文献
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Real-world networks are characterized by common features, including among others a scale-free degree distribution, a high clustering coefficient and a short typical distance between nodes. These properties are usually explained by the dynamics of edge and node addition and deletion. 相似文献
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Wan Yong Feng Moshe Goldenberg Chava Lifshitz 《Journal of the American Society for Mass Spectrometry》1994,5(8):695-703
Thermal reactions of proton-bound dimers, (CH3CN)2H +, (CH3OCH3)2H +, and (CH3COCH3)2H+, were studied using a selected ion flow tube. Reactions observed include association, switching, and proton transfer. The association channel was observed only for base molecules that had hydrogen bonding protons such as NH3, CH3NH2, (CH3)2NH, and CH3OH. An association-insertion mechaniSoc was proposed in which the central proton of the symmetrically bound dimers is replaced by a protonated base, for example, NH 4 + . These reactions are relatively slow, which demonstrates a central barrier along the potential energy surface. Ether-containing dimers do not demonstrate this insertion reaction, except for diethers, for example, CH3OCH2CH2OCH3, which can form stable bicyclic structures. Dimers such as (HCOOH)2H+, which possess hydrogen bonding protons in the periphery, undergo switching reactions with ammonia and no insertion. 相似文献
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It is demonstrated, by numerical simulations of a 2D assembly of polydisperse disks, that there exists a range (plateau) of coarse-graining scales for which the stress tensor field in a granular solid is nearly resolution independent, thereby enabling an "objective" definition of this field. Expectedly, it is not the mere size of the system but the (related) magnitudes of the gradients that determine the widths of the plateaus. Ensemble averaging (even over "small" ensembles) extends the widths of the plateaus to subparticle scales. The fluctuations within the ensemble are studied as well. Both the response to homogeneous forcing and to an external compressive localized load (and gravity) are studied. Implications to small solid systems and constitutive relations are briefly discussed. 相似文献