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51.
Norman R. Draper Irwin Guttman 《Annals of the Institute of Statistical Mathematics》1992,44(4):659-671
When an empirical model is fitted to data, bias can arise from terms that have not been incorporated, and this can have an important effect on the choice of an experimental design. Here, the biases are treated as random, and the consequences of this action are explored for the fitting of models of first and second order. 相似文献
52.
N. G. Kozlenko V. V. Abaev V. S. Bekrenev S. P. Kruglov A. A. Koulbardis I. V. Lopatin A. B. Starostin B. Draper S. Hayden J. Huddleston D. Isenhower C. Robinson M. Sadler C. Allgower R. Cadman H. Spinka J. Comfort K. Craig A. Ramirez T. Kycia M. Clajus A. Marusic S. McDonald B. M. K. Nefkens N. Phaisangittisakul S. Prakhov J. W. Price W. B. Tippens J. Peterson W. J. Briscoe A. Shafi I. I. Strakovsky H. Staudenmaier D. M. Manley J. Olmsted D. Peaslee N. Knecht G. Lolos Z. Papandreou I. Supek I. Slaus A. Gibson D. Grosnic D. Koetke R. Manweiler S. Stanislaus 《Physics of Atomic Nuclei》2003,66(1):110-113
The first results obtained in 1998 by the Crystal Ball collaboration from a measurement of the total and differential cross sections for the reaction π ? p → ηn are presented. These new experimental results for the total cross sections are compared with the predictions of the K-matrix model for pion-nucleon scattering. The angular distribution at momenta near the reaction threshold (685 MeV/c) is determined by the S-wave contribution. The P-wave contribution begins to manifest itself from a momentum of 720 MeV/c. 相似文献
53.
M. J. Brinkman A. Kuhnert E. A. Henry J. A. Becker S. W. Yates R. M. Diamond M. A. Deleplanque F. S. Stephens W. Korten F. Azaiez W. H. Kelly J. E. Draper C. W. Beausang E. Rubel J. A. Cizewski 《Zeitschrift für Physik A Hadrons and Nuclei》1990,335(1):115-116
For the first time, collective bands have been observed in the doubly-odd nucleus124Cs. They are proposed to result in the coupling of an h11/2 proton to h11/2 and positive parity neutrons. The relative residual protonneutron interaction in124Cs is calculated and compared to that of neighbouring odd-odd nuclei. 相似文献
54.
C. W. Beausang E. A. Henry J. A. Becker N. Roy S. W. Yates M. A. Deleplanque R. M. Diamond F. S. Stephens J. E. Draper W. H. Kelly J. Burde R. J. McDonald E. Rubel M. J. Brinkman J. A. Cizewski Y. A. Akovali 《Zeitschrift für Physik A Hadrons and Nuclei》1990,335(3):325-330
Two rotational bands, with energy spacings characteristic of superdeformed shapes, have been observed following bombardment of150Nd with48Ca. The more intensively populated band consists of 18 transitions and is assigned to194Hg. The depopulation of this band occurs around spin 10. The second band, consisting of at least 16 transitions, was populated less strongly and is tentatively assigned to194Hg also. The lowest level in this band is assigned spin 8. The energy differences between transitions for both bands decrease from ~40 keV at low rotational frequencies to ~30 keV at the highest observed frequencies. The moments of inertia of the bands are similar to those of the two previously observed superdeformed bands in191,192Hg. The similarities and differences of the four known bands in the mercury region are discussed. 相似文献
55.
Regine Gries Prof. Robert Britton Michael Holmes Huimin Zhai Jason Draper Prof. Gerhard Gries 《Angewandte Chemie (International ed. in English)》2015,54(4):1135-1138
Bed bugs have become a global epidemic and current detection tools are poorly suited for routine surveillance. Despite intense research on bed bug aggregation behavior and the aggregation pheromone, which could be used as a chemical lure, the complete composition of this pheromone has thus far proven elusive. Here, we report that the bed bug aggregation pheromone comprises five volatile components (dimethyl disulfide, dimethyl trisulfide, (E)‐2‐hexenal, (E)‐2‐octenal, 2‐hexanone), which attract bed bugs to safe shelters, and one less‐volatile component (histamine), which causes their arrestment upon contact. In infested premises, a blend of all six components is highly effective at luring bed bugs into traps. The trapping of juvenile and adult bed bugs, with or without recent blood meals, provides strong evidence that this unique pheromone bait could become an effective and inexpensive tool for bed bug detection and potentially their control. 相似文献
56.
Martin CJ Gil B Perera SD Draper SM 《Chemical communications (Cambridge, England)》2011,47(12):3616-3618
With a view to combining the desirable electronic and photochemical properties of hexabenzocoronene (HBC) and the C-C bond forming capabilities of thiophenes, 1-(3-thienyl)-2,3,4,5,6-penta(4-tert-butyl-phenyl)benzene (1) was oxidised using FeCl(3). The resulting products, superaromatic thiophene (2) and its 5,5'-dimer (3), are S-HBC systems and provide a new pair of spectral comparators. 相似文献
57.
Graczyk A Murphy FA Nolan D Fernández-Moreira V Lundin NJ Fitchett CM Draper SM 《Dalton transactions (Cambridge, England : 2003)》2012,41(25):7746-7754
A series of novel fused 4'-substituted 2,2'?:?6',2'-terpyridine ligands and their ruthenium(II) complexes were prepared. The unusual 4'-substituents comprised 2,3,4,5-pentaphenylbenzene and its tert-butyl derivative (1 and 2) and the products from oxidative cyclodehydrogenation, i.e. polyaromatic fragments consisting of ten or thirteen fused benzene rings (3 and 4). The syntheses of all the ligands are discussed in terms of the demands and limitations of the Scholl reaction. The optical properties of the ligands, along with the single-crystal X-ray structures of 1 and 2, are presented. The latter show that the pentaphenylbenzene and terpyridine appendages of 1 and 2 are perpendicular in the solid state. Despite the inclusion of the large organic chromophore the absorption and emission properties of the Ru(II) bis-terpy complexes (of ligands 1, 2 and 3) were found to be comparable to those of [Ru(terpy)(2)](2+). They are non-emissive at room temperature but emit at 77 K with excited state lifetimes of 11-12 μs. 相似文献
58.
59.
60.
James Stark Draper Lawrence S. Bernstein Wai K. Cheng 《Journal of Quantitative Spectroscopy & Radiative Transfer》1980,23(3):323-326
Fluctuating molecular vibrational-rotational band emission from an unsteady temperature field is formulated in terms of the intensity of the temperature fluctuation and the temperature total sensitivity function of the spectral radiance of a thin, isobaric layer. By examining the contributions of layer-density dilation, Planck's function and molecular spectral absorptivity, it is shown that this total sensitivity function can be either positive or negative with respect to layer temperature depending upon mean temperature and spectral region. The 4.3-μm CO2 band is examined to illustrate these results and a simple quantum mechanical model is presented to estimate these effects in the general case. 相似文献