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排序方式: 共有803条查询结果,搜索用时 31 毫秒
91.
92.
Hendricks K.J. Haworth M.D. Englert T. Shiffler D. Baca G. Coleman P.D. Bowers L. Lemke R.W. Spencer T.A. Arman M.J. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1998,26(3):320-325
The Air Force Research Laboratory RKO source has recently demonstrated the ability to convert electron beam power to RF power until the termination of the electron beam pulse, achieving a power of 1.5 GW at an energy of 170 J. These results represent an increase in power of 25-30% in power and energy extracted from this source. This paper discusses the principal research areas encountered in lengthening the RF pulse (FWHM) from 50 ns to the present 120 ns and the associated increase in the RF energy 相似文献
93.
Patrick Shahgaldian Anthony W. Coleman Beth Rather Michael J. Zaworotko 《Journal of inclusion phenomena and macrocyclic chemistry》2005,52(3):241-245
The crystal structure of para-octanoylcalix-[4]-arene·2 tetrahydrofuran complex reveals double inclusion of the guest molecules, one deep in the aromatic cavity and the other held in a four-fingered molecular hand formed by the aliphatic chains, the inclusion changes the molecular packing from a bilayer system in the absence of guest, to a head-to-tail antiparallel chain packing. 相似文献
94.
D. C. Coleman 《Analytical and bioanalytical chemistry》1997,357(2):209-213
In this article a brief overview of the World Wide Web (WWW) is given, with some examples of the kind of information and
services pertaining to analytical chemistry that can be found there. An existing WWW site that has been set up for analytical
chemists is used as a case in point. The article concludes with a brief look at some of the issues raised by publishing on
the Internet.
Received:15 January 1996 / Accepted: 28 January 1996 相似文献
95.
K. F. Canter P. G. Coleman T. C. Griffith G. R. Heyland 《Applied Physics A: Materials Science & Processing》1974,3(3):249
Experimentally determined values of the total scattering cross-sections for positrons in the energy range 2–400 eV on He,
Ne, Ar, Kr and Xe are presented.
Paper F 6 presented at 3rd Internal. Conf. Positron Annihilation, Otaniemi, Finland (August 1973). 相似文献
96.
R. P. Bryan J. J. Coleman R. S. Averback J. L. Klatt L. M. Miller T. M. Cockerill 《Optical and Quantum Electronics》1991,23(7):S967-S974
In recent years considerable interest has been shown in impurity-induced compositional disordering of III–V compound semiconductor devices, especially in efforts directed towards fabricating index-guided buried heterostructure lasers and other unique photonic and electronic devices. In this work we describe the study of compositional disordering induced by MeV implantation of oxygen and krypton into AlAs-GaAs superlattices and the fabrication of index-guided quantum well heterostructure lasers by MeV oxygen ion implantation. 相似文献
97.
98.
S.W Kirchoefer N Holonyak K Hess D.A Gulino H.G Drickamer J.J Coleman P.D Dapkus 《Solid State Communications》1982,42(9):633-636
Hydrostatic pressure experiments on AlxGa1?xAsGaAs quantum-well heterostructure (QWH) laser diodes are described. Data are presented giving ~11.5meV/kbar for the bandgap vs. pressure coefficient at lower pressures, with a change to 8.5–9meV/kbar at higher pressures. We suggest that this behavior is caused by biaxial and shear stresses in the active region induced by doping or composition mismatch relative to the confining layers, or between the n and p confining layers themselves. A model consistent with the experimental data is presented. 相似文献
99.
100.