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871.
Honghui Yan Xuejun Huang Weihong Lou Hongsheng Yang 《International Journal of Infrared and Millimeter Waves》1997,18(12):2343-2352
This paper gives a structure on the mode converter from TE
0n
O
mode of gyrotron output to the
main mode of the circular groove guide. The design consists of two parts: the first part is to convert TE
0n
O
to TE
01
O
using an advanced periodic wall perturbation technology, the second part is to convert TE
01
O
to
mode basing on the method of gradually changing the wave guide cross section. An example at 37.5Ghz is given. For the first
part, the efficiency is 94.71%, the length is 1.868m. For the second part, the theoretic figure of reflectance coefficient
vs. frequency is given. 相似文献
872.
Avery P Besson D Garren L Yelton J Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Ammar R Baringer P Haas P Lam H Jawahery A Park CH Nelson JK Perticone D Poling R Chen W Dominick J McIlwain RL Miller DH Ng CR Schaffner SF Shibata EI Yao W Sparks K Thorndike EH Alam MS Kim IJ Li WC Lou XC Sun CR Fulton R Hempstead M Jensen T Johnson DR Kagan H Kass R Morrow F Whitmore J Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE 《Physical review D: Particles and fields》1990,41(3):774-779
873.
874.
F. J. Hartmann P. Baumann H. Daniel T. von Egidy S. Grunewald R. Lipowsky E. Moser W. Schott P. Ackerbauer W. H. Breunlich M. Fuchs M. Jeitler P. Kammel J. Marton N. Nägele J. Werner J. Zmeskal H. Bossy K. M. Crowe R. H. Sherman K. Lou C. Petitjean V. E. Markushin 《Hyperfine Interactions》1993,82(1-4):259-269
The experiments on pt fusion performed at Paul Scherrer Institut, Villigen, Switzerland, are described. Liquid triple mixtures of protium, deuterium and tritium with low concentrations on deuterium and tritium were used. Gamma rays, X-rays, neutrons and, for the first time, conversion muons, were measured. Preliminary results are: Rate for spin flip from the triplet to the singlet state of t(1s), 10=(1.0±0.2) × 103s–1; rate for muon-catalyzed pt fusion from the (I=1) nuclear-spin state,
pt
f
(I=1)=0.07±0.01s–1; and the molecular formation rate,
pt
m
=(7.5±1.3)s–1 (all normalized to liquid hydrogen density). 相似文献
875.
876.
The structural transformation that occurs in the cadmium hydroxide decomposition reaction has the morphological and crystallographic character of a martensitic transformation. The authors predict the shape of the oxide crystallites produced during the reaction, viz., small platelets developed parallel to the (111) oxide planes. The difficulty in assessing their shape by analysis of X-ray diffraction line profiles is discussed. Electron microscope and X-ray diffraction results are presented and it is shown that the oxide crystallite shape is dependent on whether the precursor is hydroxide or carbonate. 相似文献
877.
A new synthesis of a functionalized 4-1,2-oxazete by oxidation of α,α--(alkylthio) oxime is described. 相似文献
878.
879.
Development and validation of a high performance liquid chromatography method for determination of 6‐benzyl‐1‐benzyloxymethyl‐5‐iodouracil (W‐1), a novel non‐nucleoside reverse transcriptase inhibitor and its application to a pharmacokinetic study in rats
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880.
Yunan Qing Hao Wang Yan Lou Xu Fang Shihuai Li Xingyue Wang Xin Gao Yanguo Qin 《Materials Today Chemistry》2022
The repair of critical-sized bone defects remains a major concern in clinical care. Herein, a multifunctional hydrogel is rationally designed to synergistically photothermal antibacterial and potentiate bone regeneration via adding magnesium oxide nanoparticle and black phosphorus nanosheet (BPNS) into poly(vinyl alcohol)/chitosan hydrogel (PVA/CS-MgO-BPNS). Under the dual effect of near-infrared irradiation and CS intrinsic antibacterial properties, PVA/CS-MgO-BPNS hydrogel can kill more than 99.9% of Staphylococcus aureus and Escherichia coli. The released Mg ions stimulate the migration of mesenchymal stem cells (MSCs) to hydrogels and synergize with released phosphate to promote osteogenic differentiation. The PVA/CS-MgO-BPNS hydrogel also promotes calcium phosphate particle formation and therefore improves the biomineralization ability. Furthermore, the potential molecular mechanism of PVA/CS-MgO-BPNS to regulate MSCs migration and differentiation is through activating phosphoinositide 3-kinase (PI3K)-Akt signaling pathways through RNA-seq analysis. Finally, the PVA/CS-MgO-BPNS hydrogel could significantly promote endogenous bone tissue regeneration in the rat skull defect model. Taken together, this easy fabricated multifunctional hydrogel has good clinical applicability for the repair of large-scale bone defects. 相似文献