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Journal articles on the topic 'Two-impurities'

Author: Grafiati

Published: 5 June 2025

Last updated: 25 June 2025

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1

Ferrero, Alejandro, and Gabriel Téllez. "Two-Dimensional Two-Component Plasma with Adsorbing Impurities." Journal of Statistical Physics 129, no. 4 (2007): 759–86. http://dx.doi.org/10.1007/s10955-007-9401-2.

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2

Galkin, S., C. A. Balseiro, and M. Avignon. "Two Kondo impurities in nanoscopic systems." European Physical Journal B 38, no. 3 (2004): 519–23. http://dx.doi.org/10.1140/epjb/e2004-00147-4.

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3

Xiang, T., and J. M. Wheatley. "Nonmagnetic impurities in two-dimensional superconductors." Physical Review B 51, no. 17 (1995): 11721–27. http://dx.doi.org/10.1103/physrevb.51.11721.

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4

Silva Elipe, Maria Victoria, Zhixin Jessica Tan, Michael Ronk, and Tracy Bostick. "A Multidisciplinary Investigation to Determine the Structure and Source of Dimeric Impurities in AMG 517 Drug Substance." International Journal of Analytical Chemistry 2009 (2009): 1–12. http://dx.doi.org/10.1155/2009/768743.

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In the initial scale-up batches of the experimental drug substance AMG 517, a pair of unexpected impurities was observed by HPLC. Analysis of data from initial LC-MS experiments indicated the presence of two dimer-like molecules. One impurity had an additional sulfur atom incorporated into its structure relative to the other impurity. Isolation of the impurities was performed, and further structural elucidation experiments were conducted with high-resolution LC-MS and 2D NMR. The dimeric structures were confirmed, with one of the impurities having an unexpected C-S-C linkage. Based on the synthetic route of AMG 517, it was unlikely that these impurities were generated during the last two steps of the process. Stress studies on the enriched impurities were carried out to further confirm the existence of the C-S-C linkage in the benzothiazole portion of AMG 517. Further investigation revealed that these two dimeric impurities originated from existing impurities in the AMG 517 starting material, N-acetyl benzothiazole. The characterization of these two dimeric impurities allowed for better quality control of new batches of the N-acetyl benzothiazole starting material. As a result, subsequent batches of AMG 517 contained no reportable levels of these two impurities

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5

Lipiński, S., and D. Krychowski. "Two Kondo Impurities in Armchair Graphene Nanoribbon." Acta Physica Polonica A 121, no. 5-6 (2012): 1063–65. http://dx.doi.org/10.12693/aphyspola.121.1063.

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6

Hu, Zhan-Ning, and Fu-Cho Pu. "Two magnetic impurities in a spin chain." Physical Review B 58, no. 6 (1998): R2925—R2928. http://dx.doi.org/10.1103/physrevb.58.r2925.

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7

Kumazaki, Hideki, and Dai S. Hirashima. "Effects of Impurities in Two-Dimensional Graphite." Journal of the Physical Society of Japan 75, no. 5 (2006): 053707. http://dx.doi.org/10.1143/jpsj.75.053707.

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8

Máthé, Levente, and Ioan Grosu. "Friedel Oscillations in a One-dimensional Non-interacting Electron Gas in the Presence of Two Impuritites." Studia Universitatis Babeș-Bolyai Physica 68, no. 1-2 (2023): 49–56. http://dx.doi.org/10.24193/subbphys.2023.05.

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Using the linear response theory, we analyze Friedel oscillations in a one-dimensional non-interacting electron gas in the presence of two impurities with different potential strengths. The impurities potentials are modeled using Dirac delta function, as well as Lorentzian and Gaussian distribution functions. Our findings show that density oscillations are strongly sensitive to both the distance between the impurities and their respective potential strengths. Keywords: one-dimensional electron gas, one impurity, two impurities, Friedel oscillations.

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9

Reddy, Nandyala Malyadri, K. R. S. Prasad, Ravi Sekhar Reddy Nandipati, et al. "Identification, Synthesis and Characterization of Novel Palbociclib Impurities." Asian Journal of Chemistry 37, no. 3 (2025): 698–706. https://doi.org/10.14233/ajchem.2025.33265.

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Palbociclib is used for breast cancer treatment along with letrozole. Five major impurities were observed during the synthesis as well as in forced degradation studies, out of which, three impurities were identified during the penultimate step of palbociclib API synthesis. These three impurities were confirmed as palbociclib desacetyl impurity (PDA impurity), palbociclib desacetyl hydroxy impurity (PDH impurity) and palbociclib desacetyl hydroxyl methyl impurity (PDHM impurity). These impurities were formed due to the usage of palladium catalyst during the pre-final reaction between 1 and 2. The other two impurities were identified as N-oxides, which were formed due to the forced oxidative degradation studies of palbociclib. These two impurities were confirmed as palbociclib pyridine N-oxide and palbociclib piperazine N-oxide. All the five major impurities were identified, synthesized, characterized and confirmed by spectral analyses (1H NMR, 13C NMR and mass spectra). These impurities were potentially important as reference standards for the R&D scientists working in process development and formulation development of palbociclib.

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10

SONG, YUN. "LOCAL MODES AROUND THE FERROMAGNETIC IMPURITIES IN THE TWO-DIMENSIONAL HEISENBERG ANTIFERROMAGNETS." Modern Physics Letters B 15, no. 08 (2001): 243–51. http://dx.doi.org/10.1142/s0217984901001720.

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The behaviors of the spin-wave excitations around the ferromagnetic impurities in the two-dimensional spin-1/2 Heisenberg antiferromagnets are investigated for the cases with one, two and four impurities respectively. By means of the double-time Green's function numerical procedure, it is found that, in the two impurity case, two ferromagnetic impurities prefer to form an effective singlet. While in the four impurity case we obtained that, two nearest-neighbor ferromagnetic domains with contrary spin directions are formed in the antiferromagnetic background, and thus the whole system has the lowest energy.

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11

Medhi, Amal, Saurabh Basu, and Charudatt Kadolkar. "Nonmagnetic impurities in a two-leg Hubbard ladder." Journal of Applied Physics 101, no. 9 (2007): 09D504. http://dx.doi.org/10.1063/1.2709412.

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12

Bazeia, D., M. A. Liao, and M. A. Marques. "Two-field models in the presence of impurities." Chaos, Solitons & Fractals 192 (March 2025): 115950. https://doi.org/10.1016/j.chaos.2024.115950.

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13

Savchenko, A. K., V. V. Kuznetsov, A. Woolfe, et al. "Resonant tunneling through two impurities in disordered barriers." Physical Review B 52, no. 24 (1995): R17021—R17024. http://dx.doi.org/10.1103/physrevb.52.r17021.

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14

Khalil, Saleh A. H., M. A. Y. Abu-Baker, and A. H. Al-Shareef. "HPLC determination of glibenclamide and its two impurities." Journal of Pharmacy and Pharmacology 50, S9 (1998): 50. http://dx.doi.org/10.1111/j.2042-7158.1998.tb02250.x.

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15

Allub, R. "Enhanced superconductivity by correlations between two Kondo impurities." Physica B: Condensed Matter 406, no. 9 (2011): 1738–43. http://dx.doi.org/10.1016/j.physb.2011.02.018.

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16

Ummarino, G. A. "Effects of Magnetic Impurities on Two-Band Superconductor." Journal of Superconductivity and Novel Magnetism 20, no. 7-8 (2007): 639–42. http://dx.doi.org/10.1007/s10948-007-0259-y.

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17

Schlottmann, P., and J. W. Rasul. "Low-temperature properties of two interacting magnetic impurities." Physica B: Condensed Matter 163, no. 1-3 (1990): 544–46. http://dx.doi.org/10.1016/0921-4526(90)90264-u.

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18

Luk, K. H., M. Jarrell, and D. L. Cox. "Suppression of superconductivity by two-channel Kondo impurities." Physical Review B 50, no. 21 (1994): 15864–74. http://dx.doi.org/10.1103/physrevb.50.15864.

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19

Savchenko, A. K., V. V. Kuznetsov, A. Woolfe, et al. "Resonant tunneling through two impurities in disordered barriers." Surface Science 361-362 (July 1996): 251–54. http://dx.doi.org/10.1016/0039-6028(96)00396-2.

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20

Reddy, T. Purendar, Nageshwar Dussa, Srinivas Mamidi, Mahesh Panasa, Ramadas Chavakula, and M. Padma. "Identification, Isolation and Origin of Potential Dimer Impurities of Dichlorphenamide: A Carbonic Anhydrase Inhibitor Drug (Antiglaucoma)." Asian Journal of Chemistry 33, no. 6 (2021): 1249–52. http://dx.doi.org/10.14233/ajchem.2021.23166.

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Present work describes the identification, isolation and characterization of two new process related dimeric impurities of dichlorphenamide (1). During the synthesis of dichlorphenamide, the formation of two new dimeric impurities namely 2,3-dichloro-5-(3,4-dichloro-5-sulfamoyl-phenyl)sulfonylbenzenesulfonamide (2) (1,1Œ-dichlorphenamide dimer) and 2,3-dichloro-5-(2,3-dichloro-5-sulfamoylphenyl) sulfonyl-benzenesulfonamide (3) (1,3Œ-dichlorphenamide dimer) was observed. In addition, origin and the strategies adapted to control these potential dimer impurities were also described. These impurities have a substantial impact on the quality of the drug substance as well as drug product.

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21

Gao, Shenghua, Lili Meng, Chunjie Zhao, Tao Zhang, Pengcheng Qiu, and Fuli Zhang. "Identification, Characterization and Quantification of Process-Related and Degradation Impurities in Lisdexamfetamine Dimesylate: Identifiction of Two New Compounds." Molecules 23, no. 12 (2018): 3125. http://dx.doi.org/10.3390/molecules23123125.

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Twelve impurities (process-related and degradation) in lisdexamfetamine dimesylate (LDX), a central nervous system (CNS) stimulant drug, were first separated and quantified by high-performance liquid chromatography (HPLC) and then identified by liquid chromatography mass spectrometry (LC-MS). The structures of the twelve impurities were further confirmed and characterized by IR, HRMS and NMR analyses. Based on the characterization data, two previously unknown impurities formed during the process development and forced degradation were proposed to be (2S)-2,6-di-(lysyl)-amino-N-[(1S)-1-methyl-2-phenyl ethyl]hexanamide (Imp-H) and (2S)-2,6-diamino-N-[(1S)-1-methyl-2-(2-hydroxyphenyl)ethyl] hexanamide (Imp-M). Furthermore, these two compounds are new. Probable mechanisms for the formation of the twelve impurities were discussed based on the synthesis route of LDX. Superior separation was achieved on a YMC-Pack ODS-AQ S5 120A silica column (250 × 4.6 mm × 5 μm) using a gradient of a mixture of acetonitrile and 0.1% aqueous methanesulfonic acid solution. The HPLC method was optimized in order to separate, selectively detect, and quantify all the impurities. The full identification and characterization of these impurities should prove useful for quality control in the manufacture of lisdexamfetamine dimesylate.

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22

Obispo, Angel E., Cristofher Zuñiga Vargas, and William C. Algoner. "Boosting Photovoltaic Efficiency in Double Quantum Well Intermediate Band-Solar Cells through Impurity Positioning." Energies 16, no. 23 (2023): 7722. http://dx.doi.org/10.3390/en16237722.

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The photovoltaic conversion efficiency of a single-intermediate band solar cell that incorporates a double quantum well structure consisting of GaAs/InAs/GaAs/InAs/GaAs embedded in the intrinsic region of conventional p-i-n structure is analyzed. The width of the intermediate band and the solutions for the two lowest energy states has been determined by solving the two-impurities-related Schrodinger equation based on the Numerov method. The position of these impurities determines three distinct cases: the system in the absence of impurities (Case 1), impurities at the center of GaAs quantum barriers (Case 2), and impurities at the center of InAs quantum wells (Case 3). The photovoltaic conversion efficiency has been calculated as a function of the widths L y H of the quantum well structures. The obtained results indicate an improvement in efficiency under the specific conditions of these parameters.

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23

SEN, PRASENJIT. "SELF-CONSISTENT NUMERICAL STUDIES OF MAGNETIC IMPURITIES IN HUBBARD ANTIFERROMAGNET." International Journal of Modern Physics B 13, no. 27 (1999): 3193–203. http://dx.doi.org/10.1142/s0217979299002952.

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Effects of magnetic impurities on a two-dimensional Hubbard antiferromagnet are treated self-consistently within a numerical Hartree–Fock approximation. Both kinds of impurities — those with spin equal to the host spin (S′=S); and those with spin different from the host spin (S′≠S) — have been studied. In this approach, S′=S impurities lead to momentum (Q) dependent renormalization of the long wavelength magnon energies, unlike in the previous perturbative calculations where the renormalization was found to be Q-independent. S′≠S impurities, however, give Q-dependent logarithmically diverging corrections. Both kinds of impurities leave the gapless Goldstone mode in the spin excitations unaffected.

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24

Skripnik, Yu V., E. S. Syrkin, and S. B. Feodos’ev. "Low-temperature heat capacity of two-component substitutional solutions." Low Temperature Physics 19, no. 10 (1993): 801–5. https://doi.org/10.1063/10.0033515.

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The low-frequency dynamics of a lattice containing two-parametric substitutional impurities is studied over a wide concentration range. The restrictions for the method of coherent potential are considered, and analytic expressions for the concentration dependence of low-temperature heat capacity are derived. The results of the analysis are illustrated by numerical calculations of the change in the vibrational spectrum due to two-parametric substitutional impurities.

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25

Jones, B. A., and C. M. Varma. "Study of two magnetic impurities in a Fermi gas." Physical Review Letters 58, no. 9 (1987): 843–46. http://dx.doi.org/10.1103/physrevlett.58.843.

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26

Ciccarello, Francesco, G. Massimo Palma, Michelangelo Zarcone, Yasser Omar, and Vitor R. Vieira. "Electron Fabry–Perot interferometer with two entangled magnetic impurities." Journal of Physics A: Mathematical and Theoretical 40, no. 28 (2007): 7993–8008. http://dx.doi.org/10.1088/1751-8113/40/28/s09.

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27

Chernyshev, A. L., Y. C. Chen, and A. H. Castro Neto. "Effect of impurities on quasi-two-dimensional quantum antiferromagnet." Journal of Applied Physics 91, no. 10 (2002): 8387. http://dx.doi.org/10.1063/1.1456911.

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28

Schiller, A., and V. Zevin. "Kondo versus antiferromagnetic ground state of two Anderson impurities." Physical Review B 47, no. 21 (1993): 14297–300. http://dx.doi.org/10.1103/physrevb.47.14297.

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29

Li, Jian, and Yupeng Wang. "Magnetic impurities in the two-band s ± -wave superconductors." EPL (Europhysics Letters) 88, no. 1 (2009): 17009. http://dx.doi.org/10.1209/0295-5075/88/17009.

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30

Jones, B. A., B. G. Kotliar, and A. J. Millis. "Mean-field analysis of two antiferromagnetically coupled Anderson impurities." Physical Review B 39, no. 5 (1989): 3415–18. http://dx.doi.org/10.1103/physrevb.39.3415.

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31

Schlottmann, P. "Integrable model for two interacting magnetic impurities withΓ8ground multiplet". Physical Review B 59, № 5 (1999): 3624–34. http://dx.doi.org/10.1103/physrevb.59.3624.

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32

Mashkevich, Stefan, Jan Myrheim, and Stéphane Ouvry. "Quantum mechanics of a particle with two magnetic impurities." Physics Letters A 330, no. 1-2 (2004): 41–47. http://dx.doi.org/10.1016/j.physleta.2004.07.040.

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33

Sun, Yi, Xuchu Huang, and Guanghui Min. "Pairwise entanglement of two impurities in the XY model." Physics Letters A 381, no. 4 (2017): 387–91. http://dx.doi.org/10.1016/j.physleta.2016.11.030.

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34

Dupont-Ferrier, E., P. Mallet, L. Magaud, and J. Y. Veuillen. "Bound states at impurities in a two-dimensional metal." Europhysics Letters (EPL) 72, no. 3 (2005): 430–36. http://dx.doi.org/10.1209/epl/i2005-10263-3.

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35

Ng, Tai-Kai. "Nonmagnetic impurities in two- and three-dimensional Heisenberg antiferromagnets." Physical Review B 54, no. 17 (1996): 11921–24. http://dx.doi.org/10.1103/physrevb.54.11921.

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36

Riera, J., S. Koval, D. Poilblanc, and F. Pantigny. "Pair breaking by impurities in the two-dimensionalt-Jmodel." Physical Review B 54, no. 10 (1996): 7441–44. http://dx.doi.org/10.1103/physrevb.54.7441.

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37

Gaididei, Yu B., K. Ø. Rasmussen, and P. L. Christiansen. "Nonlinear excitations in two-dimensional molecular structures with impurities." Physical Review E 52, no. 3 (1995): 2951–62. http://dx.doi.org/10.1103/physreve.52.2951.

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38

Katsuno, Hiroyasu, and Masahide Sato. "Cluster diffusion on two-dimensional surface with immobile impurities." Journal of Crystal Growth 401 (September 2014): 504–7. http://dx.doi.org/10.1016/j.jcrysgro.2013.10.050.

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39

Gummich, Ute, and I. C. da Cunha Lima. "Interaction between two magnetic impurities in a quantum well." Solid State Communications 76, no. 6 (1990): 831–33. http://dx.doi.org/10.1016/0038-1098(90)90636-p.

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40

Lischner, Johannes. "Multiscale modelling of charged impurities in two-dimensional materials." Computational Materials Science 160 (April 2019): 368–73. http://dx.doi.org/10.1016/j.commatsci.2019.01.012.

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41

Panochko, Galyna, and Volodymyr Pastukhov. "Static Impurities in a Weakly Interacting Bose Gas." Atoms 10, no. 1 (2022): 19. http://dx.doi.org/10.3390/atoms10010019.

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We present a comprehensive discussion of the ground-state properties of dilute D-dimensional Bose gas interacting with a few static impurities. Assuming the short-ranged character of the boson-impurity interaction, we calculated the energy of three- and two-dimensional Bose systems with one and two impurities immersed.

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42

Fuwa, Masahiro, and Masahide Sato. "Effect of impurities on tiling in a two-dimensional dodecagonal quasicrystal." Japanese Journal of Applied Physics 61, no. 4 (2022): 045504. http://dx.doi.org/10.35848/1347-4065/ac5530.

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Abstract Langevin dynamics simulations are performed to examine how impurities affect two-dimensional dodecagonal quasicrystals. We assumed that the interaction potential between two particles is the Lennard–Jones–Gauss potential if at least one of these particles is a matrix particle and that the interaction potential between two impurities is the Lennard–Jones potential. Matrix particles and impurities impinge with constant rates on the substrate created by a part of a dodecagonal quasicrystal consisting of square and triangular tiles. The dependences of the twelve-fold rotational order and the number of shield-like tiles on the impurity density are examined after sufficient solid layers are grown. While the change in the twelve-fold rotational symmetry is small, the number of shield-like tiles in the solid increases greatly with increasing impurity density.

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43

Zhang, Dandan, Weijian Wang, Haiyun Zhao, et al. "Structural Identification of Impurities in Pioglitazone Hydrochloride Preparations by 2D-UHPLC-Q-Exactive Orbitrap HRMS and Their Toxicity Prediction." International Journal of Analytical Chemistry 2023 (October 17, 2023): 1–12. http://dx.doi.org/10.1155/2023/2096521.

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Pharmaceutical companies and regulatory agencies have more and more concerns for impurities in pharmaceuticals and their toxicity. In this work, heart-cutting two-dimensional ultrahigh-performance liquid chromatography (2D-UHPLC) in combination with high-resolution mass spectrometry (HRMS) was used, setting HRMS as positive mode of electrospray ionization to identify five impurities in pioglitazone hydrochloride preparations. With the heart-cutting 2D-UHPLC and online desalting technique, the structures of five impurities were deduced in an analysis of MSn data. And three of them, Impurity-2, Impurity-3, and Impurity-5, have never been reported before. The fragmentation patterns of five impurities were proposed on a basis of accurate mass and fragment ions in this study. Since the toxicity of impurities is relevant to their structures, toxicology of all five impurities was predicted by three software tools, and the result showed that these compounds have good safety profile.

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44

Feng, Wei-Dong, Song-Ming Zhuo, and Fu-Li Zhang. "Synthesis and characterization of new impurities in obeticholic acid." Journal of Chemical Research 43, no. 11-12 (2019): 522–30. http://dx.doi.org/10.1177/1747519819875858.

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Novel and efficient synthetic strategies are developed for the first synthesis of two new impurities found in obeticholic acid. The synthetic routes to the impurities are designed without column purification using 4-nitrobenzoyl chloride as a selective protecting group. The impurities, which are obtained in good yields and high purity, are identified and characterized using high-resolution mass spectrometry, Fourier transform infrared, one-dimensional nuclear magnetic resonance (1H, 13C, distortionless enhancement by polarization transfer), and two-dimensional nuclear magnetic resonance (Correlated Spectroscopy, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, and rotating-frame Overhauser effect spectroscopy) techniques.

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45

Prasad Ketha, Naga Venkata Durga, and Deepti Kolli. "USING PREPARATIVE CHROMATOGRAPHY AND NMR/LCMS/FT-IR, ISOLATION, IDENTIFICATION, AND CHARACTERIZATION OF POSACONAZOLE OXIDATIVE DEGRADATION IMPURITIES." Rasayan Journal of Chemistry 15, no. 01 (2022): 619–27. http://dx.doi.org/10.31788/rjc.2022.1516707.

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Posaconazole is a pharmacological ingredient that is used to treat fungal infections. It comes in the form of delayedrelease tablets. During the forced degradation studies of Tablets, two unknown oxidative degradation impurities were discovered. The impurities were made from Posaconazole using meta-Chloroperoxybenzoic acid as an oxidant in the degradation process. Preparative chromatography was used to separate impurities, and spectroscopic techniques such as IR, NMR, and MS were used to deduce the structures. For the measurement of the total of six associated impurities of Posaconazole in Delayed-Release Tablets, a reverse phase HPLC technique was developed and validated according to ICH Q2 criteria

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46

Smith, P., and J. Narayan. "Dislocation and solid-phase epitaxial growth microstructure control by Ar+ implantation for gettering in semiconductors." Proceedings, annual meeting, Electron Microscopy Society of America 44 (August 1986): 728–29. http://dx.doi.org/10.1017/s0424820100145017.

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Gettering of undesirable impurities from the junctions or the electrically active regions improves electrical characteristics of semiconductor devices. This removal of impurities can be accomplished either by point defects or more efficiently by line defects such as dislocations and small-angle grain boundaries. The small-angle grain boundaries containing arrays of dislocations constitute two-dimensional defects which are more effective in removing the impurities. This removal of undesirable impurities involves dislocation - impurity interaction and subsequent segregation of impurities at the dislocations. The gettering efficiency of dislocations is determined by the nature of dislocations and also by the stability of dislocation network against annealing. In previous studies, it has been shown Ar+ implantation damage is very effective in gettering undesireable impurities. However, the mechanisms of enhanced gettering by Ar+ ion damage were not clear. The purpose of this investigation was to explore the mechanism of enhanced gettering by Ar+ damage and charaterize the Ar+ damage as a function of annealing treatments.

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47

Studzińska, Sylwia, Feiyang Li, Michał Szumski, Bogusław Buszewski, and Michael Lämmerhofer. "Cholesterol Stationary Phase in the Separation and Identification of siRNA Impurities by Two-Dimensional Liquid Chromatography-Mass Spectrometry." International Journal of Molecular Sciences 23, no. 23 (2022): 14960. http://dx.doi.org/10.3390/ijms232314960.

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The aim of this research was to develop a simple and efficient ion-pair reagent-free chromatographic method for the separation and qualitative determination of oligonucleotide impurities, exemplified by synthesis of raw products of the two single strands of patisiran siRNA. The stationary phases with mixed hydrophobic/hydrophilic properties (cholesterol and alkylamide) were firstly used for this purpose with reversed-phased high-performance liquid chromatography. Several different chromatographic parameters were tested for their impact on impurities separation: type, concentration, pH of salt, as well as organic solvent type in the mobile phase. The pH was the most influential factor on the separation and signal intensities in mass spectrometry detection. Finally, the optimized method included the application of cholesterol stationary phase, with mobile phase containing 20 mM ammonium formate (pH 6.5) and methanol. It allowed good separation and the identification of most impurities within 25 min. Since not all closely related impurities could be fully resolved from the main peak in this oligonucleotide impurity profiling, two-dimensional liquid chromatography was used for peak purity determination of the target oligonucleotides. The Ethylene Bridged Hybrid (BEH) Amide column in hydrophilic interaction liquid chromatography was applied in the second dimension, allowing additional separation of three closely related impurities.

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48

Tsuruta, Atsushi, and Kazumasa Miyake. "Unconventional non-Fermi liquid properties of two-channel Anderson impurities system." Journal of Physics Communications 6, no. 1 (2022): 015006. http://dx.doi.org/10.1088/2399-6528/ac42dd.

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Abstract A theory for treating the unconventional non-Fermi liquid temperature dependence of physical quantities, such as the resistivity, in the Pr-based two-channel Anderson impurities system is developed. It is shown that their temperature dependences are essentially the same as those in the pure lattice system except for the case of extremely low concentration of Pr ions that is difficult to realize by the controlled experiments. This result is consistent with recent observations in diluted Pr-1-2-20 system Y1−x Pr x Ir2Zn20 (x = 0.024, 0.044, 0.085, and 0.44) reported in Yamane et al (2018) Phys. Rev. Lett. 121, 077206, and is quite different from that in the case of single-channel Anderson impurities system in which the crossover between behaviors of the local Fermi liquid and heavy Fermi liquid occurs at around moderate concentration of impurities as observed in Ce-based heavy fermion system La1−x Ce x Cu6.

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49

Sun, Yongqiang, Xinyu Zhang, Yimin Yan, et al. "Identification and genotoxicity evaluation of two carbamate impurities in rasagiline." RSC Advances 6, no. 108 (2016): 106268–74. http://dx.doi.org/10.1039/c6ra20810j.

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During the synthesis of a second-generation monoamine oxidase-B inhibitor rasagiline, two unknown impurities (impurity A and impurity B) were detected and isolated by preparative liquid chromatography.

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Allub, R. "Magnetic correlations between two Kondo impurities with two magnetic configurations: Narrow-band limit." Physica B: Condensed Matter 421 (July 2013): 34–40. http://dx.doi.org/10.1016/j.physb.2013.04.009.

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