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101.
Seongsin M.Kim William Baughman David S.Wilbert Lee Butler Michael Bolus Soner Balci Patrick Kung 《中国光学快报(英文版)》2011,(11):46-49
We demonstrate two distinct emerging terahertz (THz) biomedical imaging techniques.One is based on the use of a new single frequency THz quantum cascade laser and the other is based on broadband THz time domain spectrocopy.The first method is employed to derive a metastasis lung tissue imaging at 3.7 THz with clear contrast between cancerous and healthy areas.The second approach is used to study an osseous tissue under several imaging modalities and achieve full THz spectroscopic imaging based on the freque... 相似文献
102.
With the advance of atomic absorption spectroscopy and the degree of automation obtained in instruments today, the preparation of calibration curves and the ensuing calculations are, apart from the sample preparation in certain cases, the most time consuming part of an atomic absorption analysis. It is usually at this stage that errors are introduced, either as a result of miscalculation or of the operator's personal bias. Both these factors can be overcome by using a programmable desk calculating system, and would be of special importance to laboratories where routine analyses are conducted. It is also of use in cases where elements are only determined periodically. 相似文献
103.
We introduce a class of set-functions on the set of natural numbers, which are called super-measures. Super-measures are then
utilized to characterize a certain class of topological measures (previously called quasi-measures, see below) which arises
naturally. The members of this class of topological measures are called finitely defined, and are shown to be dense in the
set of all topological measures.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
104.
105.
H. L. Seifert J. M. Wouters D. J. Vieira H. Wollnik X. G. Zhou X. L. Tu Z. Y. Zhou G. W. Butler 《Zeitschrift für Physik A Hadrons and Nuclei》1994,349(1):25-32
The ground state masses of thirty-nine neutronrich nuclei from51Ca to72Ni have been measured using the Time-of-Flight Isochronous (TOFI) spectrometer. Eight of these masses have been measured for the first time and thirty-one are remeasurements of neutron-rich nuclei previously reported. Good agreement between these results and a previous TOFI experiment was observed except for the most neutron-rich isotopes of vanadium through iron with the present results being more bound and in better agreement with theory. The low binding energy of68Ni, as indicated by an unreasonably low two-neutron separation energy, suggests the presence of a high-lying, long-lived isomeric state in this nucleus. 相似文献
106.
107.
108.
A novel low temperature technique has been developed for the synthesis of celsian glass-ceramics. The technique involves ion exchange of zeolites, their subsequent heat treatment to form a glassy phase from which celsian is crystallized. Monoclinic celsian was produced at temperatures as low as 1000°C at heat treatment times of 6 h. 相似文献
109.
The structure of diaquo(1,2-dimethoxyethane)lithium tetraphenylborate, [Li(CH3OCH2-CH2OCH3)(H2O)2][BPh4], has been determined at 293 K. The compound crystallizes in the trigonal P3(1)21 space group (a = b = 9.9760(14), c = 23.662(5)). Both the lithium and the boron sit on a twofold rotation axis. The lithium is coordinated to two water oxygens and both ether oxygens of the 1,2-dimethoxyethane group. The coordination geometry is significantly distorted from a tetrahedron by the twisting of the plane containing the two water oxygens and the lithium relative to that containing the two 1,2-dimethoxyethane oxygens and the lithium. The five-membered chelate ring formed by chelation of the 1,2-dimethoxyethane to the lithium is a twist envelope consistent with the twofold rotation axis passing through the lithium and the center of the carbon–carbon bond of the 1,2-dimethoxyethane. Hydrogen bonding between each water hydrogen and a phenyl group of the tetraphenylborate is observed and results in a linear polymeric structure. 相似文献
110.
Reinhardt J. Heuer Robert Thayer Sataloff Kate Emerich Rhonda Rulnick Margaret Baroody Joseph R. Spiegel Gursel Durson John Butler 《Journal of voice》1997,11(1):88-94
This preliminary retrospective study of 19 female patients and 22male patients with unilateral recurrent nerve lesions demonstrated the promise of objective measurements in predicting the need for surgery, the efficacy of voice therapy in ameliorating vocal symptoms, and the effects of therapy in conjunction with surgery. Sixty-eight percent (68%) of the female patients and 64% of the male patients did not elect to have surgery. Outcome satisfaction of nonsurgical and surgical patients appeared to be similar. The data from this study support the importance of preoperative therapy for patients with unilateral vocal fold paralysis. 相似文献