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81.
A photochemical decomposition study of NO2(B?2B2) in specified vibronic states is reported. The O(1D)-atom yields below and above the dissociation limit (40973 cm?1) have been measured. The role played by the rotational excitation energy and the vibrational excitation modes in promoting the predissociation is discussed. 相似文献
82.
Substantially purified insulin-like growth factor II (IGF-II) was prepared from human serum. Initial enrichment using ion-exchange chromatography on DEAE Sephadex A50, followed by gel permeation chromatography on Sephadex G-75 in 1% formic acid produced material suitable for application to a preparative reversed-phase high-performance liquid chromatographic (HPLC) column containing LiChroprep RP-18. The latter step gave about 90-fold purification with a recovery of about 70% IGF-II bio-activity. Finally, a small reversed-phase HPLC column achieved a 17-fold purification with similar yield of activity. Overall, the four steps gave IGF-II of about 90% purity in yield of 12%. 相似文献
83.
The compound {2-exo-bicyclo [2.2.1] hept-exo-3-acetato-5-enyl}-5,10,15,20-tetraphenylporphinatothallium (III) has been synthesized and its molecular structure determined. The compound crystallizes in the monoclinic space group P21, with a 13.112, b 29.193, c 11.249 Å, β 102.17°, Z = 4. The organothallium(III) group is situated above the plane of the porphyrin ring with the thallium atom displaced 0.9 Å from the N4 plane. The thallium atom and the acetato group are attached cis-exo to the bicyclo [2.2.1] unit. Carbon-13 spectra show shielding effects arising from the porphyrin ring current. 相似文献
84.
Molecular dynamics simulations of pure water employing two different empirical water models have been used to study the effects of different methods for truncation of long-range interactions in molecular mechanics calculations. As has been observed previously in integral equation studies, “shifting” these interactions on an atom-by-atom basis was found to produce artificial structuring in the water and affect diffusion rates. In cases where some form of short-range truncation must be used, the ST2 switching function applied on a group-by-group basis was found to be the most realistic procedure. If atom-based shifting must be employed, a cutoff distance greater than or equal to 12.0 Å was found to be required to produce realistic results. © 1993 John Wiley & Sons, Inc. 相似文献
85.
Adam D. Morris Daniel L. D. Freitas Kssio M. G. Lima Lauren Floyd Mark E. Brady Ajay P. Dhaygude Anthony W. Rowbottom Francis L. Martin 《Molecules (Basel, Switzerland)》2022,27(7)
Biospectroscopy offers the ability to simultaneously identify key biochemical changes in tissue associated with a given pathological state to facilitate biomarker extraction and automated detection of key lesions. Herein, we evaluated the application of machine learning in conjunction with Raman spectroscopy as an innovative low-cost technique for the automated computational detection of disease activity in anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis (AAGN). Consecutive patients with active AAGN and those in disease remission were recruited from a single UK centre. In those with active disease, renal biopsy samples were collected together with a paired urine sample. Urine samples were collected immediately prior to biopsy. Amongst those in remission at the time of recruitment, archived renal tissue samples representative of biopsies taken during an active disease period were obtained. In total, twenty-eight tissue samples were included in the analysis. Following supervised classification according to recorded histological data, spectral data from unstained tissue samples were able to discriminate disease activity with a high degree of accuracy on blind predictive modelling: F-score 95% for >25% interstitial fibrosis and tubular atrophy (sensitivity 100%, specificity 90%, area under ROC 0.98), 100% for necrotising glomerular lesions (sensitivity 100%, specificity 100%, area under ROC 1) and 100% for interstitial infiltrate (sensitivity 100%, specificity 100%, area under ROC 0.97). Corresponding spectrochemical changes in paired urine samples were limited. Future larger study is required, inclusive of assigned variables according to novel non-invasive biomarkers as well as the application of forward feature extraction algorithms to predict clinical outcomes based on spectral features. 相似文献
86.
John J. Brady Elizabeth J. Judge Robert J. Levis 《Rapid communications in mass spectrometry : RCM》2009,23(19):3151-3157
Intact, nonvolatile, biological macromolecules can be transferred directly from the solid state into the gas phase, in ambient air, for subsequent mass spectral analysis using non‐resonant femtosecond (fs) laser desorption combined with electrospray ionization (ESI). Mass spectral measurements for neat samples, including a dipeptide, protoporphyrin IX and vitamin B12 adsorbed on a glass insulating surface, were obtained using an 800 nm, 70 fs laser with an intensity of 1013 W cm−2. No appreciable signal was detected when atmospheric matrix‐assisted or neat (matrix‐free) fs laser desorption was performed without ESI, indicating neutral desorption. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
87.
J. Wilczynski J. Hansmeyer F.P. Brady P. Doll W. Heeringa J.C. Hiebert H.O. Klages P. Plischke 《Nuclear Physics A》1984,425(3):458-468
Measurements of the analyzing power Ay for neutron-proton scattering in the energy range from 17 to 50 MeV are reported. These data improve considerably the precision of the np data base in this energy range. Preliminary phase-shift analyses indicate reduced uncertainties in the np 3P(T = 1) phases and in the 3D(T = 0) phase shifts. 相似文献
88.
Abbott B Abbott R Adhikari R Ageev A Allen B Amin R Anderson SB Anderson WG Araya M Armandula H Ashley M Asiri F Aufmuth P Aulbert C Babak S Balasubramanian R Ballmer S Barish BC Barker C Barker D Barnes M Barr B Barton MA Bayer K Beausoleil R Belczynski K Bennett R Berukoff SJ Betzwieser J Bhawal B Bilenko IA Billingsley G Black E Blackburn K Blackburn L Bland B Bochner B Bogue L Bork R Bose S Brady PR Braginsky VB Brau JE Brown DA Bullington A Bunkowski A Buonanno A Burgess R Busby D 《Physical review letters》2005,94(18):181103
We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars. 相似文献
89.
Brady SK Conradi MS Vaccaro CM 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2005,172(2):342-345
Composite materials of epoxy resins reinforced by carbon fibers are increasingly being used in the construction of aircraft. In these applications, the material may be thermally damaged and weakened by jet blast and accidental fires. The feasibility of using proton NMR relaxation times T1, T1rho, and T2 to detect and quantify the thermal damage is investigated. In conventional spectrometers with homogeneous static magnetic fields, T1rho is readily measured and is found to be well correlated with thermal damage. This suggests that NMR measurements of proton T1rho may be used for non-destructive evaluation of carbon fiber-epoxy composites. Results from T1rho measurements in the inhomogeneous static and RF magnetic fields of an NMR-MOUSE are also discussed. 相似文献
90.
Elliott JB Moretto LG Phair L Wozniak GJ Albergo S Bieser F Brady FP Caccia Z Cebra DA Chacon AD Chance JL Choi Y Costa S Gilkes ML Hauger JA Hirsch AS Hjort EL Insolia A Justice M Keane D Kintner JC Lindenstruth V Lisa MA Matis HS McMahan M McParland C 《Physical review letters》2000,85(6):1194-1197
It is shown that the Fisher droplet model, percolation, and nuclear multifragmentation share the common features of reducibility (stochasticity in multiplicity distributions) and thermal scaling (one-fragment production probabilities are Boltzmann factors). Barriers obtained, for cluster production on percolation lattices, from the Boltzmann factors show a power-law dependence on cluster size with an exponent of 0.42+/-0.02. The EOS Collaboration Au multifragmentation data yield barriers with a power-law exponent of 0.68+/-0.03. Values of the surface energy coefficient of a low density nuclear system are also extracted. 相似文献