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91.
We report μSR measurements on a series of compounds with composition La2-xSrxNiO4+\delta where the net hole concentration x+2\delta is greater than 0.4. A magnetic transition is found in all the samples studied which occurs at a composition‐dependent temperature TM. Below TM, clear precession signals are observed in zero applied magnetic field. The possible muon sites are discussed within the context of dipole‐field calculations. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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An instrumented pendulum-type impact tester was used to obtain tensile-impact properties for compact bone. Load-time histories throughout impact were recorded. Impact tests on 50 longitudinally oriented fresh-beef-bone samples yielded a proportional limit of 9.6±4.1 ksi (66.2±28.2 MPa), an ultimate stress of 17.6±5.3 ksi (121.3±36.5 MPa) and an energy-absorption capacity of 142±85 in. Ib/in.2 (24900±14900 J/m2). A static tensile strength of 14.7±2.8 ksi (101±19 MPa) was obtained from static testing of 24 additional specimens. The tensile-impact strength was 20 percent higher than the static strength. Statistically significant correlations between elastic properties, impact strength and impact energy were found. Bone microstructure and fracture-surface topography were also examined.  相似文献   
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A number of new 2- and 2,7-aryl substituted phenanthrenes, 3,4-dihydrophenanthrenes, and 9,10-dihydrophenanthrenes, as well as some relatedp-quaterphenyls andp-terphenyls, were tested as liquid scintillation solutes. Also determined were the compounds' ultraviolet absorption spectra, ultraviolet-induced fluorescence spectra, and Kallmann parameters. On the basis of these measurements, it was possible to correlate to some degree structure and scintillation ability. Some interesting results regarding conjugation and co-planarity in the linear polyphenyls were also obtained.  相似文献   
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The photoionization cross section and asymmetry parameter are reported for hydrogen molecule-ion. The calculations were performed using the dipole length and dipole velocity operators in the energy range from threshold to 270 eV photon energy. The results indicate that the calculations are very sensitive to the accuracy of the bound state wavefunction, and that the velocity operator gives more accurate results.  相似文献   
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Gas chromatography (GC) is the most widely used analytical technique in the food and beverage industry. This paper addresses the problems of sample preparation and system maintenance to ensure the most sensitive, durable, and efficient results for trace analysis by GC in this industry.  相似文献   
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Summary Extended X-ray absorption fine-structure (EXAFS) spectroscopy has been demonstrated to be a most useful probe of short-range interatomic correlations in a wide variety of materials. The theory of the EXAFS is presented in its simplest form so as to provide the basis for a discussion about the kind and quality of the structural information which can be extracted from EXAFS data. The adequacy of several of the approximations commonly incorporated in this theory is examined with emphasis on those areas of the theory which bear most directly on the analysis of EXAFS data. Paper presented at the Workshop on ?EXAFS Data Analysis in Disordered Systems?, held in Parma, October 5–7, 1981.  相似文献   
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