Journal articles: 'Nuclear spectra'

1

Buck, B., A. C. Merchant, and S. M. Perez. "Recurring nuclear band spectra." Journal of Physics: Conference Series 111 (May 1, 2008): 012011. http://dx.doi.org/10.1088/1742-6596/111/1/012011.

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2

Kunakov, S. K., E. E. Son, Zh Bolatov, and M. Kaster. "Optical spectra in helium plasma generated by nuclear fission fragments." International Journal of Mathematics and Physics 6, no. 1 (2015): 75–81. http://dx.doi.org/10.26577/2218-7987-2015-6-1-75-81.

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3

Leonidov, A., M. Nardi, and H. Satz. "Hadron spectra from nuclear collisions." Nuclear Physics A 610 (December 1996): 124–31. http://dx.doi.org/10.1016/s0375-9474(96)00348-x.

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Leonidov, A., M. Nardi, and H. Satz. "Hadron spectra from nuclear collisions." Zeitschrift f�r Physik C Particles and Fields 74, no. 3 (May 1, 1997): 535–40. http://dx.doi.org/10.1007/s002880050416.

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Mitchell, G. E., E. G. Bilpuch, P. M. Endt, J. F. Shriner, and T. von Egidy. "Chaotic behavior of nuclear spectra." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 56-57 (May 1991): 446–50. http://dx.doi.org/10.1016/0168-583x(91)96067-u.

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6

Mesilaakso, Markku, Eeva-Liisa Tolppa, and Paula Nousiainen. "Analysis of 1H and 13C{1H} NMR Spectral Parameters of Diphenylchloroarsine, Diphenylcyanoarsine, and 10-Chloro- 5,10-Dihydrophenarsazine: Identification of the Compounds through Reference to Simulated Spectra." Applied Spectroscopy 51, no. 5 (May 1997): 733–37. http://dx.doi.org/10.1366/0003702971940891.

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The 1H and 13C{1H} nuclear magnetic resonance (NMR) spectra of diphenylchloroarsine, diphenylcyanoarsine, and 10-chloro-5,10-dihydrophenarsazine were recorded from samples prepared in CDCl3, CD2Cl2, and (CD3)2CO. Spectra were analyzed, and detailed 1H NMR spectral parameters were determined by iterative analysis. Simulation of spectra and their use as reference spectra for identification of the compounds under different conditions are discussed.

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7

Malik, Zvi, Chana Rothmann, Tova Cycowitz, Zwi J. Cycowitz, and Amos M. Cohen. "Spectral Morphometric Characterization of B-CLL Cells Versus Normal Small Lymphocytes." Journal of Histochemistry & Cytochemistry 46, no. 10 (October 1998): 1113–18. http://dx.doi.org/10.1177/002215549804601003.

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Spectral morphometric characterization of typical chronic lymphocytic leukemia (B-CLL) cells vs normal small lymphocytes stained by May-Grunwald-Giemsa was carried out by multipixel spectral imaging. The light intensity (450–850 nm of 104 pixels) from nuclear domains of each stained cell was recorded and represented as light transmittance spectra and optical density. Transmitted light spectra of two nuclear domains were determined, one with low-intensity light transmittance (LIT) and the other with high-intensity light transmittance (HIT). A spectral library was constructed using the four transmitted light spectra representing the HIT and LIT domains of the normal human lymphocytes and the LIT and HIT domains of the CLL cells. The spectral library served to scan CLL lymphocytes from 10 cases of CLL and the lymphocytes of 10 healthy individuals. Each spectrally similar domain in the nuclei of the lymphocytes was assigned an arbitrary color. The morphometric analysis of the spectrally classified nuclei showed specific spectral patterns for B-CLL in 92% of the cells. The specific spectral characteristics of each of the two cell populations were also observed by their optical density light absorbance spectra. We propose that spectral morphometric analysis may serve as an additional diagnostic tool for detection of CLL lymphocytes in a hematological specimen.

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Tsakstara, V., T. S. Kosmas, and J. Sinatkas. "Nuclear response to supernova neutrino spectra." HNPS Proceedings 18 (November 23, 2019): 187. http://dx.doi.org/10.12681/hnps.2551.

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In current probes searching for rare event processes, appropriate nuclear targets are employed (in the COBRA double-beta decay detector the CdZnTe semiconductor is used). In this work the response of such detectors to various low-energy neutrino spectra is explored starting from state-by-state calculations of the neutrino-nucleus reactions cross sections obtained by using the quasi particle random phase approximation (QRPA) based on realistic two-body residual interactions. As a concrete example, we examine the response of 64Zn isotope to low energy supernova neutrinos.

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Almoukhalalati, Adel, Avijit Shee, and Trond Saue. "Nuclear size effects in vibrational spectra." Physical Chemistry Chemical Physics 18, no. 22 (2016): 15406–17. http://dx.doi.org/10.1039/c6cp01913g.

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Reshetnikov, V. P., M. Faúndez-Abans, and M. de Oliveira-Abans. "Nuclear spectra of polar-ring galaxies." Monthly Notices of the Royal Astronomical Society 322, no. 4 (April 2001): 689–94. http://dx.doi.org/10.1046/j.1365-8711.2001.04134.x.

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Wu, Hong, Zhenlong Zou, Xiaoyang Xia, and Zugan Deng. "The Spectra of Very Luminous IRAS Galaxies." International Astronomical Union Colloquium 159 (1997): 443–44. http://dx.doi.org/10.1017/s0252921100040719.

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AbstractWe discuss new optical spectra and DSS images of a complete sample of very luminous IRAS galaxies. The statistics of classification of spectral types and interactions show that interaction can account for the nuclear activity (AGN and starburst) of ultraluminous infrared galaxies.

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12

Fedorova, E., B. I. Hnatyk, and V. I. Zhdanov. "Radio-loud AGNs with peculiar shape of hard X-ray spectrum: figuring out the reasons." Proceedings of the International Astronomical Union 14, S342 (May 2018): 218–19. http://dx.doi.org/10.1017/s1743921318005136.

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AbstractWe analyze the hard X-ray properties of five radio-loud active galactic nuclei with peculiar spectral shape. High-energy exponential cut-offs (HEC) in their hard X-ray 3-500 keV spectra are too high for radio loud AGNs (above 100 keV) or even absent.The probable reason of such visible spectral “peculiarity” can be due to the “jet contamination”, i.e we see some mixture of the jet and nuclear emission, but not pure emission of the innermost nucleus. Here we try to estimate the jet and nuclear components of the spectra for a sample of “peculiar” RL AGNs to find out whether these are real or fake features.

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13

Baumgardt, Douglas R., and Kathleen A. Ziegler. "Spectral evidence for source multiplicity in explosions: Application to regional discrimination of earthquakes and explosions." Bulletin of the Seismological Society of America 78, no. 5 (October 1, 1988): 1773–95. http://dx.doi.org/10.1785/bssa0780051773.

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Abstract Spectral and cepstral analysis were performed on regional-array NORESS recordings of mining explosions in Scandinavia and Russia in order to detect the effects of delayed explosions or “ripple firing” commonly used in mine-blasting practice. NORESS array-stacked spectra, corrected for instrument and noise, were computed in windows on Pn, Pg, Sn, and Lg waves from the mine blasts by averaging individual channel spectra, frequency by frequency, across the array. For comparison, spectra were also computed for six western Norway earthquakes located near the Blasjo and Titania Norwegian mines. Also, stack spectra of P coda, Sn, and Lg were computed using NORSAR seismograms for presumed peaceful nuclear explosions (PNEs) located at near-regional distances (Δ > 10°) in western Russia. The NORSAR spectra were determined in the same manner as the NORESS spectra, except that an individual source correction was applied to the spectra. Comparison of western Norway mine-blast spectra and nearby earthquakes shows that the earthquake Pn spectra are peaked in the 8- to 16-Hz band, with little energy below 6 Hz, whereas the explosion spectra have flatter spectra from 3 to 16 Hz. This difference in the Pn spectra may be caused by the earthquakes occurring at greater depths than the explosions, differences in the near-source media, or source mechanism effects in the earthquake spectra. The main difference between earthquake and explosion spectra is that the explosion spectra exhibit marked scalloping or modulation patterns not observed in the earthquake spectra. The modulation patterns are identical in spectra of all phases, indicating that they are caused by multiple-shot sequences or ripple firing. Simulated multiple-source spectra, determined using the NORESS seismograms for one of the western Norway earthquakes, resulted in spectra that resembled many of the explosion modulation patterns. Based on the simulation studies and cepstral analysis of the spectra, the mine explosions appear to be composed of two to three separate explosions delayed by between 80 to 150 msec. Moreover, the NORSAR spectra of PNEs indicate that these signals are also produced by multiple explosions, although they have larger delay times of between 0.9 to 1.5 sec. These results show that spectral modulations in seismogram spectra of economic explosions, including mine explosions and nuclear explosions fired for peaceful, economic purposes, can be used to distinguish them from earthquakes and nuclear-explosion weapons tests.

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14

Bell, Jimmy D., Judith C. C. Brown, Peter J. Sadler, Andrew F. MacLeod, Peter H. Sönksen, Robin D. Hughes, and Roger Williams. "High resolution proton nuclear magnetic resonance studies of human cerebrospinal fluid." Clinical Science 72, no. 5 (May 1, 1987): 563–70. http://dx.doi.org/10.1042/cs0720563.

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1. One- and two-dimensional (correlated shift spectroscopy) high resolution proton n.m.r. spectra of human cerebrospinal fluid (CSF) are reported. The merits of water suppression by freeze drying or irradiation, and spectral simplification by spin-echo methods, are discussed. 2. Well-resolved resonances for a range of low molecular weight metabolites such as lactate, 3-d-hydroxybutyrate, alanine, acetate, citrate, glucose, valine and formate were observed. Resonances for glutamine were observed only from freeze dried samples. Concentrations determined by n.m.r. were in reasonable agreement with those from conventional methods. 3. The n.m.r. spectra of CSF were related to the clinical conditions of the subjects. No resonances for citrate were present in spectra of CSF from subjects (three infants) with bacterial meningitis; high lactate and lowered glucose levels were observed. Strong resonances for glucose and glycine were observed for mildly diabetic subjects. Both the aromatic and the aliphatic regions of the CSF spectra from subjects suffering from liver failure contained distinctive features characteristic for hepatic coma: intense resonances for lactate, alanine, valine, methionine, tyrosine, phenylalanine and histidine. In some cases guanine was also present, which does not appear to have been reported previously. The two-dimensional spectrum suggested the presence of abnormally high levels of a number of endogenous metabolites. Such assignments were not possible using one-dimensional spectra alone because of signal overlap.

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15

Sevast’yanov, V. D., A. S. Koshelev, and G. N. Maslov. "Forming a priori neutron spectra of nuclear facilities using Maxwellian spectra." Instruments and Experimental Techniques 51, no. 5 (September 2008): 694–98. http://dx.doi.org/10.1134/s0020441208050072.

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16

Forouzangohar, Mohsen, Jeffrey A. Baldock, Ronald J. Smernik, Bruce Hawke, and Lauren T. Bennett. "Mid-infrared spectra predict nuclear magnetic resonance spectra of soil carbon." Geoderma 247-248 (June 2015): 65–72. http://dx.doi.org/10.1016/j.geoderma.2015.02.006.

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17

Raevsky, A. M., A. G. Gukalova, and G. K. Semin. "Nuclear Quadrupole Resonance of Antimony in Ln3Sb5O12 Crystals." Zeitschrift für Naturforschung A 49, no. 6 (June 1, 1994): 687–89. http://dx.doi.org/10.1515/zna-1994-0605.

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Abstract Complete 121,123Sb NQR spectra of crystalline rate earth antimonites Ln3Sb5O12 (Ln = La, Nd, Er, Lu) were recorded at 77 K. The quadrupole coupling constants and asymmetry parameters of the electric field gradient were measured. A “lanthanide compression” effect on the antimony NQR was observed. Using relations found for the antimonites under study, the Sb spectral parameters of other lanthanide compounds can be predicted.

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18

McLean, Stewart, Marion Perpick-Dumont, William F. Reynolds, Helen Jacobs, and Sagar Singh Lachmansing. "Unambiguous structural and nuclear magnetic resonance spectral characterization of two triterpenoids of Maprouneaguianensis by two-dimensional nuclear magnetic resonance spectroscopy." Canadian Journal of Chemistry 65, no. 11 (November 1, 1987): 2519–25. http://dx.doi.org/10.1139/v87-420.

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It is shown that 1H–13C shift-correlated two-dimensional spectra obtained for polarization transfer via two-bond and three-bond 13C–1H coupling can, in conjunction with related experiments, be used to assign unambiguously the molecular skeletons of two of the less common triterpenes, moretenone and 3-acetylaleuritolic acid. It is concluded that this is a technique of considerable generality for assigning structures of triterpenes and is more reliable than alternative approaches such as mass spectral fragmentation patterns. It has the additional benefit of simultaneously providing reliable 13C and 1H spectral assignments for these compounds.

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19

Herbers, Sven, Philipp Buschmann, Juan Wang, Kevin Gregor Lengsfeld, K. P. Rajappan Nair, and Jens-Uwe Grabow. "Reactivity and rotational spectra: the old concept of substitution effects." Physical Chemistry Chemical Physics 22, no. 20 (2020): 11490–97. http://dx.doi.org/10.1039/d0cp01145b.

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The internal rotation of methyl groups and nuclear quadrupole moments of the halogens Cl, Br, I in o-halotoluenes result in complex spectral fine and hyperfine structures in rotational spectra which can be related to qualitative concepts in chemistry.

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Singh, Manjeet, Raman Kumar Mishra, Amar Kumar, Chetan Parkash Kaushik, P. G. Jaison, and Arnab Sarkar. "Comparison of univariate and multivariate data analysis models for uranium quantification in Trombay historical nuclear waste glass." Radiochimica Acta 106, no. 6 (June 27, 2018): 453–63. http://dx.doi.org/10.1515/ract-2017-2859.

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Abstract Laser induced breakdown spectroscopy recently has been investigated for analysis of nuclear waste glass for uranium quantification. The initial obtained accuracy and precision was ~15%. In this paper, we have compared the analytical merit of the univariative and multivariative PLSR regression models for the determination of U in barium borosilicate simulated waste glass containing significant amount of U. The analytical merit of a Czerny-Turner spectrograph with high spectral resolution and Echelle spectrograph with broadband spectrum recording capacity were compared using spectra simultaneously record from the same plasma. For univariative calibration the superiority of Czerny-Turner spectrograph over the Echelle has been demonstrated here. Multivariative chemometric PLSR model was found to drastically improve the results. It was also observed that selection of spectral window for analysis significantly affects the analytical merit of multivariative analysis. Echelle though shows relatively inferior analytical merit, but by applying Analytical spectral dependant PLSR in Echelle spectra, a much higher degree of improvement was observed. Using ASD-PLSR and Czerny-Turner spectrograph generated spectra an accuracy and precision of 2–2.5% was achieved in this study.

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Lin, Yanqin, Qing Zeng, Liangjie Lin, and Zhong Chen. "High Resolution Nuclear Magnetic Resonance Spectroscopy on Biological Tissue and Metabolomics." Current Medicinal Chemistry 26, no. 12 (July 1, 2019): 2190–207. http://dx.doi.org/10.2174/0929867326666190312130155.

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High-resolution nuclear magnetic resonance (NMR) spectroscopy is a universal analytical tool. It can provide detailed information on chemical shifts, J coupling constants, multiplet patterns, and relative peak areas. It plays an important role in the fields of chemistry, biology, medicine, and pharmacy. A highly homogeneous magnetic field is a prerequisite for excellent spectral resolution. However, in some cases, such as in vivo and ex vivo biological tissues, the magnetic field inhomogeneity due to magnetic susceptibility variation in samples is unavoidable and hard to eliminate by conventional methods. The techniques based on intermolecular multiple quantum coherences and conventional single quantum coherence can remove the influence of the field inhomogeneity effects and be applied to obtain highresolution NMR spectra of biological tissues, including in vivo animal and human tissues. Broadband 1H homo-decoupled NMR spectroscopy displays J coupled resonances as collapsed singlets, resulting in highly resolved spectra. It can be used to acquire high-resolution spectra of some pharmaceuticals. The J-difference edited spectra can be used to detect J coupled metabolites, such as γ-aminobutyric acid, the detection of which is interfered by intense neighboring peaks. High-resolution 1H NMR spectroscopy has been widely utilized for the identification and characterization of biological fluids, constituting an important tool in drug discovery, drug development, and disease diagnosis.

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Bakibaev, А. А., М. Zh Sadvakassova, V. S. Malkov, R. Sh Еrkasov, A. A. Sorvanov, and O. A. Kotelnikov. "Study of the biologically active acyclic ureas by nuclear magnetic resonance." Bulletin of the Karaganda University. "Chemistry" series 100, no. 4 (December 30, 2020): 60–74. http://dx.doi.org/10.31489/2020ch4/60-74.

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A wide variety of acyclic ureas comprising alkyl, arylalkyl, acyl, and aryl functional groups are investigated by nuclear magnetic resonance spectroscopy. In general, spectral characteristics of more than 130 substances based on acyclic ureas dissolved in deuterated dimethyl sulfoxide at room temperature are studied. The re-sults obtained based on the studies of 1H and 13C NMR spectra of urea and its N-alkyl-, N-arylalkyl-, N-aryl- and 1,3-diaryl derivatives are presented, and the effect of these functional groups on the chemical shifts in carbonyl and amide moieties in acyclic urea derivatives is discussed. An introduction of any type of substitu-ent (electron-withdrawing or electron-donating) into urea molecule is stated to result in a strong upfield shift in 13C NMR spectra relatively to unsubstituted urea. A strong sensitivity of NH protons to the presence of acyl and aryl groups in nuclear magnetic resonance spectra is pointed out. In some cases, qualitative depend-encies between the chemical shifts in the NMR spectra and the structure of the studied acyclic ureas are re-vealed. A summary of the results on chemical shifts in the NMR spectra of the investigated substances allows determining the ranges of chemical shift variations of the key protons and carbon atoms in acyclic ureas. The literature describing the synthesis procedures are provided. The results obtained significantly expand the methods of reliable identification of biologically active acyclic ureas and their metabolites that makes it promising to use NMR spectroscopy both in biochemistry and in clinical practice.

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23

Misch, G. Wendell, Yang Sun, and George Fuller. "Nuclear Neutrino Spectra in Late Stellar Evolution." EPJ Web of Conferences 178 (2018): 04005. http://dx.doi.org/10.1051/epjconf/201817804005.

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Neutrinos are the principle carriers of energy in massive stars, beginning from core carbon burning and continuing through core collapse and after the core bounce. In fact, it may be possible to detect neutrinos from nearby pre-supernova stars. Therefore, it is of great interest to understand the neutrino energy spectra from these stars. Leading up to core collapse, beginning around core silicon burning, nuclei become dominant producers of neutrinos, particularly at high neutrino energy, so a systematic study of nuclear neutrino spectra is desirable. We have done such a study, and we present our sd-shell model calculations of nuclear neutrino energy spectra for nuclei in the mass number range A = 21 – 35. Our study includes neutrinos produced by charged lepton capture, charged lepton emission, and neutral current nuclear deexcitation. Previous authors have tabulated the rates of charged current nuclear weak interactions in astrophysical conditions, but the present work expands on this not only by providing neutrino energy spectra, but also by including the heretofore untabulated neutral current de-excitation neutrino pairs.

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24

Reinov, Oleg I. "Some remarks on spectra of nuclear operators." Open Mathematics 16, no. 1 (April 26, 2018): 453–60. http://dx.doi.org/10.1515/math-2018-0043.

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AbstractWe give criteria for the spectra of some nuclear operators in subspaces of quotients of Lp-spaces to be central-symmetric, as well as for the spectra of linear operators in Banach spaces to be Zd-symmetric in the sense of B. Mityagin. Also, we present a short proof of a corresponding Mityagin’s theorem.

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25

Yuliastuti, Yuliastuti, Heri Syaeful, Arifan J. Syahbana, Euis E. Alhakim, and Tagor M. Sembiring. "ONE DIMENSIONAL SEISMIC RESPONSE ANALYSIS AT THE NON-COMMERCIAL NUCLEAR REACTOR SITE, SERPONG - INDONESIA." Rudarsko-geološko-naftni zbornik 36, no. 2 (2021): 1–10. http://dx.doi.org/10.17794/rgn.2021.2.1.

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One dimensional seismic response analysis on the ground surface of the Non-Commercial Power Reactor (RDNK) site based on the mean uniform hazard spectrum (UHS) and disaggregation analysis has been conducted. The study’s objective was to perform an analysis on site-specific response spectra on the ground surface based on existing mean UHS and disaggregation data of the site that correspond to a 1,000 and 10,000 year return period of earthquakes in compliance with the national nuclear regulatory body requirements of Indonesia. Detailed site characterization was defined based on secondary data of a geotechnical drill-hole, seismic cross-hole, downhole data, and microtremor array data. The dynamic site characteristic analysis was presented along with strong motion selection and processing using two types of strong motion datasets. An investigation of strong motion selection, spectral matching, and scaling has been presented as an essential step in ground motion processing. One-dimensional equivalent linear analysis simulation was performed by computing the processed ground motions. A seismic design spectrum and ground surface response spectra from the two datasets of strong motion, both corresponding to a 10,000 and 1,000 year return period, are presented at the end of this study. This study has shown that in order to establish the appropriate seismic response design spectrum, site-specific data and seismic hazard analysis must be immensely considered.

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26

Xu, Long Jun, and Sheng Chao Yang. "Near-Fault Directivity Spectrum for Nuclear Structure Design on Rock Site." Advanced Materials Research 243-249 (May 2011): 3820–23. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.3820.

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This study is aimed at evaluating the safety implications of near-fault directivity effect on nuclear structure and facilities designed according to the Chinese code. To this end, a set of near-fault ground motions at rock site with typical forward-directivity effect is examined with emphasis on several key parameters and response spectra. The bi-normalized response spectra in terms of different corner periods are utilized to derive nuclear design spectra. It was concluded that nuclear design spectra on rock site derived from typical directivity records are significantly influenced by both magnitude and distance. The nuclear design spectra specified in the code need to be adjusted to reflect the near-fault directivity effect of large earthquakes.

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27

Bonatsos, Dennis, C. Daskaloyannis, S. B. Drenska, N. Karoussos, J. Maruani, N. Minkov, P. P. Raychev, and R. P. Roussev. "Staggering Effects in Nuclear and Molecular Spectra." HNPS Proceedings 10 (December 5, 2019): 231. http://dx.doi.org/10.12681/hnps.2193.

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It is shown that the recently observed AI = 2 staggering seen in superdeformed nuclear bands is also occurring in certain electronically excited rotational bands of diatomic molecules, in which it is attributed to interband interactions (bandcrossings). In addition, a AI = 1 staggering effect (i.e. a relative displacement of the levels with even angular momentum I with respect to the levels of the same band with odd /) is seen in molecular bands free from AI = 2 staggering (i.e. free from interband interactions/bandcrossings). The magnitude of the AI = 1 staggering is found to be constant as a function of 7, in agreement with the predictions of algebraic models (u(ll) model, u(16) model, Vector Boson Model) used for the description of octupole nuclear bands, i.e. bands corresponding to pear-like shapes, suggesting that the presence of AI = 1 staggering in rotational bands of diatomic molecules could be attributed in general to the inequality of the masses of the two atoms of which the molecule is composed. The existence of the AI = 1 staggering effect is corroborated by the fact that separate Dunham expansions for the even levels and the odd levels of such bands give similar but different parameter sets.

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28

Chapovsky, P. L. "Hyperfine spectra of CH3F nuclear spin conversion." Journal of Physics B: Atomic, Molecular and Optical Physics 33, no. 5 (March 1, 2000): 1001–11. http://dx.doi.org/10.1088/0953-4075/33/5/314.

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29

Yamagami, C., N. Takao, and Y. Takeuchi. "15N Nuclear Magnetic Resonance Spectra of Phenylacetanilides." Australian Journal of Chemistry 41, no. 1 (1988): 1. http://dx.doi.org/10.1071/ch9880001.

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15 N substituent chemical shifts (SCS) of a variety of anticonvulsant phenylacetanilides (1) and (2), with a substituent at the para or meta position of the aniline moiety, were analysed by means of DSP (dual substituent parameter) equations. For the sake of comparison, 15N scs of p-substituted anilines (3), and 13C chemical shifts of some ring carbons of (1) and (3) were also investigated. The similarity observed for the correlation of the carbon shifts para to the substituent for (1) and (3) indicates that the nitrogen shifts will be a better probe for the transmission of the substituent effect to nitrogen.

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30

Drożdż, S., S. Nishizaki, J. Speth, and J. Wambach. "Modeling complex nuclear spectra: Regularity versus chaos." Physical Review C 49, no. 2 (February 1, 1994): 867–70. http://dx.doi.org/10.1103/physrevc.49.867.

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31

Campins, Humberto, Javier Licandro, Noemí Pinilla-Alonso, Julie Ziffer, Julia de León, Thais Mothé-Diniz, Juan C. Guerra, and Carl Hergenrother. "Nuclear Spectra of Comet 28P Neujmin 1." Astronomical Journal 134, no. 4 (August 27, 2007): 1626–33. http://dx.doi.org/10.1086/519974.

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32

Feng, Pan, Luo Yan'an, and J. P. Draayer. "A New Expression for Nuclear Rotational Spectra." Communications in Theoretical Physics 31, no. 3 (April 30, 1999): 421–28. http://dx.doi.org/10.1088/0253-6102/31/3/421.

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33

Sarantites, D. G., C. Baktash, N. G. Nicolis, G. Garcia-Bermudez, V. Abenante, J. R. Beene, N. R. Johnson, et al. "Nuclear-structure effects in proton evaporation spectra." Physical Review Letters 64, no. 18 (April 30, 1990): 2129–32. http://dx.doi.org/10.1103/physrevlett.64.2129.

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34

Desvaux, Hervé, Denis J Y. Marion, Gaspard Huber, and Patrick Berthault. "Nuclear Spin-Noise Spectra of Hyperpolarized Systems." Angewandte Chemie International Edition 48, no. 24 (June 2, 2009): 4341–43. http://dx.doi.org/10.1002/anie.200901034.

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Desvaux, Hervé, Denis J Y. Marion, Gaspard Huber, and Patrick Berthault. "Nuclear Spin-Noise Spectra of Hyperpolarized Systems." Angewandte Chemie 121, no. 24 (June 2, 2009): 4405–7. http://dx.doi.org/10.1002/ange.200901034.

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36

Leander, G. A. "Simulation of nuclear quasicontinuum gamma-ray spectra." Computer Physics Communications 47, no. 2-3 (November 1987): 311–40. http://dx.doi.org/10.1016/0010-4655(87)90117-2.

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37

Wolynec, E., V. A. Serrao, and M. N. Martins. "Nuclear size effects in virtual photon spectra." Journal of Physics G: Nuclear Physics 13, no. 4 (April 1987): 515–26. http://dx.doi.org/10.1088/0305-4616/13/4/015.

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38

Minkov, N., S. B. Drenska, P. Yotov, and W. Scheid. "Complex shape effects in nuclear rotational spectra." Physics of Atomic Nuclei 67, no. 9 (September 2004): 1760–65. http://dx.doi.org/10.1134/1.1806920.

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39

Hara, K., and G. A. Lalazissis. "Analysis ofΔI=2staggering in nuclear rotational spectra." Physical Review C 55, no. 4 (April 1, 1997): 1789–96. http://dx.doi.org/10.1103/physrevc.55.1789.

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40

Smith, Leland L., Josef E. Herz, and Edward L. Ezell. "17O nuclear magnetic resonance spectra of steriods." Steroids 58, no. 6 (June 1993): 260–67. http://dx.doi.org/10.1016/0039-128x(93)90070-4.

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Méray, L. "Deconvolution of nuclear spectra of low counts." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 353, no. 1-3 (December 1994): 272–75. http://dx.doi.org/10.1016/0168-9002(94)91655-1.

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Antušek, Andrej, Karol Jackowski, Michał Jaszuński, Włodzimierz Makulski, and Marcin Wilczek. "Nuclear magnetic dipole moments from NMR spectra." Chemical Physics Letters 411, no. 1-3 (August 2005): 111–16. http://dx.doi.org/10.1016/j.cplett.2005.06.022.

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Batley, M., J. W. Redmond, and A. J. Wicken. "Nuclear magnetic resonance spectra of lipoteichoic acid." Biochimica et Biophysica Acta (BBA) - Biomembranes 901, no. 1 (July 1987): 127–37. http://dx.doi.org/10.1016/0005-2736(87)90264-1.

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Jain, A. K., S. Pal, and S. B. Bonde. "Elastic response spectra for nuclear blast loading." Computers & Structures 36, no. 2 (1990): 379–86. http://dx.doi.org/10.1016/0045-7949(90)90136-p.

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Vizkelethy, G. "Simulation and evaluation of nuclear reaction spectra." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 45, no. 1-4 (January 1990): 1–5. http://dx.doi.org/10.1016/0168-583x(90)90771-l.

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Otvos, James D., Irina Shalaurova, Justyna Wolak-Dinsmore, Margery A. Connelly, Rachel H. Mackey, James H. Stein, and Russell P. Tracy. "GlycA: A Composite Nuclear Magnetic Resonance Biomarker of Systemic Inflammation." Clinical Chemistry 61, no. 5 (May 1, 2015): 714–23. http://dx.doi.org/10.1373/clinchem.2014.232918.

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Abstract BACKGROUND Nuclear magnetic resonance (NMR) spectra of serum obtained under quantitative conditions for lipoprotein particle analyses contain additional signals that could potentially serve as useful clinical biomarkers. One of these signals that we named GlycA originates from a subset of glycan N-acetylglucosamine residues on enzymatically glycosylated acute-phase proteins. We hypothesized that the amplitude of the GlycA signal might provide a unique and convenient measure of systemic inflammation. METHODS We developed a spectral deconvolution algorithm to quantify GlycA signal amplitudes from automated NMR LipoProfile® test spectra and assessed analytic precision and biological variability. Spectra of acute-phase glycoproteins and serum fractions were analyzed to probe the origins of the GlycA signal. GlycA concentrations obtained from archived NMR LipoProfile spectra of baseline plasma from 5537 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) were used to assess associations with demographic and laboratory parameters including measures of inflammation. RESULTS Major acute-phase protein contributors to the serum GlycA signal are α1-acid glycoprotein, haptoglobin, α1-antitrypsin, α1-antichymotrypsin, and transferrin. GlycA concentrations were correlated with high-sensitivity C-reactive protein (hsCRP) (r = 0.56), fibrinogen (r = 0.46), and interleukin-6 (IL-6) (r = 0.35) (all P < 0.0001). Analytic imprecision was low (intra- and interassay CVs 1.9% and 2.6%, respectively) and intraindividual variability, assessed weekly for 5 weeks in 23 healthy volunteers, was 4.3%, lower than for hsCRP (29.2%), cholesterol (5.7%), and triglycerides (18.0%). CONCLUSIONS GlycA is a unique inflammatory biomarker with analytic and clinical attributes that may complement or provide advantages over existing clinical markers of systemic inflammation.

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BOLLER, THOMAS. "MATTER UNDER STRONG GRAVITY: THE NUCLEAR REGIONS OF AGN." International Journal of Modern Physics D 13, no. 07 (August 2004): 1509–18. http://dx.doi.org/10.1142/s0218271804005742.

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X-ray observations of Seyfert galaxies and quasars currently provide the most powerful way to study the environments of supermassive black holes. Our ability to probe these environments, some of the most extreme found in nature, is rapidly improving driven by dramatic advances in X-ray spectroscopic instrumentation. In addition to the well known 'hard X-ray power law' that is probably formed in a hot 'corona' above a cooler accretion disc, substantial spectral complexity has also been revealed. For example, soft X-ray excess emission above the power law is often seen at low X-ray energies, and this emission is thought to be associated with the inner disc. Atomic absorption/emission processes in nuclear gas flows are also observed to imprint characteristic features on X-ray spectra. Iron Kα emission lines from 6.40–6.97 keV are formed at least partially by fluorescence in the inner disc, and absorption edges seen mainly below 2 keV reveal major flows of ionized gas in the nucleus. Studies of the complex X-ray spectra of Seyferts and quasars have undergone a revolution wit the launches of Chandra in 1998 and XMM-Newton in 1999. The era of high-resolution X-ray spectroscopy has been initiated by the Chandra and XMM-Newton grating spectrometers. These detectors provide X-ray spectra with 6–100 times higher spectral resolution than those previously available, and they have dramatically enlarged the arsenal of diagnostics available for investigating Seyfert/quasar nuclei. The new generation of X-ray observatories is used to intensively address some of the leading questions about Seyfert/quasar X-ray emission. Some of the most important scientific issues for the next years are: — Matter under strong gravity: Why are relativistically blurred Fe K lines so rare? — What are the extreme X-ray spectral and variability properties of ultrasoft Narrow-Line Seyfert 1 galaxies telling us about Seyferts and quasars more generally? — What is the physical nature of the sharp spectral cut-off in Seyfert galaxies? While the advances expected from the new generation of X-ray observatories are so large and widespread that precise predictions are difficult, it is believed that particularly important progress will be made towards answering these central questions. Below is explained why the questions I have stated are fundamental and timely.

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Rothmann, Chana, Amos M. Cohen, and Zvi Malik. "Chromatin Condensation in Erythropoiesis Resolved by Multipixel Spectral Imaging: Differentiation Versus Apoptosis." Journal of Histochemistry & Cytochemistry 45, no. 8 (August 1997): 1097–108. http://dx.doi.org/10.1177/002215549704500807.

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Chromatin condensation and nuclear organization of May–Grunwald–Giemsa (MGG)-stained normal erythropoietic bone marrow cells and apoptotic red cell precursors were resolved by spectral bio-imaging. Multipixel spectra were obtained from single cells displaying a range of wavelengths of both transmitted and absorbed light. Two groups of spectra, of low- and high-intensity transmitted light, were revealed in the nuclei of each cell. The absorbance spectra served for the reconstruction of “absorbance images” depicting the affinity of MGG stain for the chromatin of proerythroblasts and of basophilic, polychromatic, and orthochromatic normoblasts. The localization of different spectral components in the nuclei was resolved employing two mathematical methods, spectral similarity mapping and principal component analysis. Novel structures of high symmetry revealing windmill-like organization were detected in basophilic, polychromatic, and orthochromatic normoblast cells. Matching structures were detected in apoptotic normoblasts obtained from an agnogenic myeloid metaplasia patient. Apoptosis was associated with a gradual breakdown of the ordered arrays in the nucleus. We propose that DNA cleavage may lead to fragmentation of the symmetrical windmill-like superstructure of the basic nuclear domains. (J Histochem Cytochem 45:1097–1108, 1997)

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Gavazzi, G., G. Consolandi, S. Belladitta, A. Boselli, and M. Fossati. "Nuclear versus integrated spectroscopy of galaxies in the Herschel Reference Survey." Astronomy & Astrophysics 615 (July 2018): A104. http://dx.doi.org/10.1051/0004-6361/201832631.

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Context. The determination of the relative frequency of active galactic nuclei (AGN) versus other spectral classes, for example, HII region-like (HII), transition objects (TRAN), passive (PAS), and retired (RET), in a complete set of galaxies in the local Universe is of primary importance to discriminate the source of ionization in the nuclear region of galaxies (e.g., supermassive black holes vs. young and old stars). Aims. Here we aim to provide a spectroscopic characterization of the nuclei of galaxies belonging to the Herschel Reference Survey (HRS), a volume and magnitude limited sample representative of the local Universe, which has become a benchmark for local and high-z studies, for semianalytical models and cosmological simulations. The comparison between the nuclear spectral classification and the one determined on the global galactic scale provides information about how galaxy properties change from the nuclear to the outer regions. Moreover, the extrapolation of the global star formation (SF) properties from the SDSS fiber spectroscopy compared to the one computed by Hα photometry can be useful for testing the method based on aperture correction for determining the global star formation rate for local galaxies. Methods. By collecting the existing nuclear spectroscopy available from the literature, complemented with new observations obtained using the Loiano 1.52 m telescope, we analyze the 322 nuclear spectra of HRS galaxies; their integrated spectroscopy is available from the literature as well. Results. Using two diagnostic diagrams (the BPT and the WHAN) we provide a nuclear and an integrated spectral classification for the HRS galaxies. The BPT and the WHAN methods for nuclei consistently give a frequency of 53–64% HII, around 21–27% AGNs (including TRAN), and 15–20% of PAS (including RET), whereas for integrated spectra they give 69–84% HII, 4–11% of AGNs and 12–20% PAS. Solely among late-type galaxies (LTGs) do the nuclear percentages become 67–77% HII, 22–27% AGNs (including TRAN), and only 1–7% of PAS. For the integrated spectra these frequencies become: 80–85% HII, 9–11% AGNs and 4–9% PAS. Conclusions. We find that the fraction of HII region-like spectra is strongly anticorrelated with the stellar mass. On the contrary the frequency of AGNs increases significantly with stellar mass, such that at M* > 1010.0 M⊙~ 66% of the LTGs are AGNs or TRAN. Moreover there is not a significant dependence of the frequency of AGNs as a function of environment: AGNs+TRAN above 109.0 M⊙ are consistent with ~30% irrespective of their membership to the Virgo cluster, suggesting that the AGNs population is not sensitive to the environment. Finally, extrapolation of the global SF properties from the nuclear spectroscopy including aperture corrections leads to underestimates with respect to values derived from direct integrated Hα photometry.

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Singh, Abhilasha, Xavier Mougeot, Benoit Sabot, Didier Lacour, and Abdel-Mjid Nourreddine. "Experimental study of 𝛽 spectra using Si detectors." EPJ Web of Conferences 239 (2020): 02001. http://dx.doi.org/10.1051/epjconf/202023902001.

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Several scientific users from different communities, such as nuclear medicine, ionizing radiation metrology, nuclear energy industries, and fundamental physics are seeking for a precise knowledge of beta spectra. Consequently, it is of great interest to investigate the spectral shape of beta decaying nuclei with best possible precision. In this work, we aim to investigate precisely β~ decays. For this purpose, we have developed a quasi 4π beta spectrometer based on Silicon detectors (PIPS®). The measurement system is characterized by conversion electron peaks of 109Cd and 207Bi and has been compared with Monte Carlo simulations using nuclear decay data. The preliminary measurements of 14C (allowed transition) and 36Cl (second forbidden non-unique transition) decays have been performed and compared with simulations using the PENELOPE Monte Carlo code.

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Journal articles on the topic 'Nuclear spectra'

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