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Journal articles on the topic 'CF2'

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Published: 4 June 2021

Last updated: 5 February 2022

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1

Malacarne, Massimo, Andrea Summer, Paolo Formaggioni, Piero Franceschi, Sandro Sandri, Mauro Pecorari, Paola Vecchia, and Primo Mariani. "Dairy maturation of milk used in the manufacture of Parmigiano-Reggiano cheese: effects on physico-chemical characteristics, rennet-coagulation aptitude and rheological properties." Journal of Dairy Research 75, no. 2 (May 2008): 218–24. http://dx.doi.org/10.1017/s0022029908003221.

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The aim of this research was to study the effects of dairy maturation on the physico-chemical characteristics and technological properties of milk used for Parmigiano-Reggiano cheese manufacture. Three different operating conditions (CF1, CF2 and CF3) were considered. Full cream milk from the evening milking was stored on the farm and delivered to the cheese factory in churns (CF1) or in thermoregulated tanks at a temperature not lower than 18°C (CF2 and CF3). The natural creaming (10–12 h overnight) was performed in a traditional large flat vat containing 10–12 hl (CF1 and CF2) or in thermoregulated large flat vats containing 60 hl at about 15°C (CF3). Twenty-four, 24 and 22 maturation trials were performed in CF1, CF2, and CF3, respectively, during 2 consecutive years. A significant increase (P⩽0·05) in pH during the maturation of milk was observed in CF1 and CF2. The increase of pH was higher (P⩽0·05) in CF1 than CF2 and CF3. The values of titratable acidity were higher (P⩽0·05) in partially skimmed evening (PS) milk than in full cream (FC) milk in each operative condition. The increase observed in CF2 was higher than those reported in CF1 and CF3. Compared with FC milk, PS milk showed lower values (P⩽0·05) of casein and casein number and higher contents (P⩽0·05) of whey proteins and, particularly, proteose-peptone. The increase of proteose-peptone – per 100 g SNF or 100 g casein – was significantly higher (P⩽0·05) in CF1 than in CF2 and, in particular, than in CF3. A higher increase (P⩽0·05) of resistance to compression was observed in CF1 with respect to CF3. CF2 variation was not different with respect to either CF1 or CF3. Variation of the difference between PS and FC milks (PS-FC) in pH, TBC and fat were clearly lower in CF3 than CF1. This means that the control of milk temperature throughout the whole maturation phase offers a greater control of both microbial development and extent of creaming.

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2

Olsen, J. F., and N. Suga. "Combination-sensitive neurons in the medial geniculate body of the mustached bat: encoding of relative velocity information." Journal of Neurophysiology 65, no. 6 (June 1, 1991): 1254–74. http://dx.doi.org/10.1152/jn.1991.65.6.1254.

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1. Orientation sounds (pulses) emitted by the mustached bat (Pteronotus parnellii) consist of up to four harmonics (H1-4); each harmonic contains a constant frequency (CF) component and a terminal frequency modulated (FM) component, so that there are eight components in total (CF1-4 and FM1-4). By referring the echo from a target to the emitted pulse, the mustached bat derives velocity information from Doppler shift and distance information from echo delay. In this study, the responses of single neurons in the medial geniculate body (MGB) to synthetic biosonar signals were investigated. Stimuli consisted of CF, FM, and CF-FM sounds. Paired CF-FM sounds were used to mimic any two harmonics of pulse-echo pairs. The dorsal and medial divisions of the MGB were found to contain combination-sensitive neurons. These neurons responded poorly to individual sounds regardless of frequency and amplitude and were facilitated by paired sounds presented at particular frequencies, amplitudes and inter-component intervals (simulated echo delay). Combination-sensitive neurons were tuned to the frequencies that characterize particular components of natural biosonar signals and were classified according to the components of pulse-echo pairs that best matched the spectral selectivity of the neuron. Two classes of combination-sensitive neurons were found, CF/CF and FM-FM. This paper focuses on CF/CF combination-sensitive neurons, which extract velocity information from paired CF components, and on CF2 and CF3 neurons, which, although not combination-sensitive, are tuned to the frequencies of the CF2 and CF3 components of biosonar signals. 2. CF2 and CF3 neurons were sharply tuned in frequency. The best frequencies of the most sharply tuned CF2 neurons were all approximately equal to 61.17 kHz (SD = 370 Hz), which closely matches the frequency at which P. parnellii stabilizes the CF2 component of an echo when compensating for Doppler shift. Thus CF2 neurons are specialized for a fine analysis of Doppler-compensated echoes. 3. Tuning curves of CF2 and CF3 neurons remained narrow regardless of stimulus level. When compared at high stimulus levels (30 and 50 dB above minimum threshold), bandwidths of tuning curves of CF2 and CF3 neurons were much smaller than those of peripheral auditory neurons turned to CF2 or CF3 frequencies but were about the same as those of cortical neurons tuned to CF2 or CF3 frequencies. Thus the sharpening of neural tuning curves by the bat's central auditory system occurs within or before the MGB.(ABSTRACT TRUNCATED AT 400 WORDS)

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3

Tran, Huong Thu Thi, Tong Xuan Nguyen, Yen Hai Thi Trinh, Hang Thi To, Huyen Thanh Thi Dang, Linh Thuy Thi Vu, Phuong Thi Nguyen, and Thuy Thu Dinh. "Using biochar from spent coffee grounds to treat pollution in livestock wastewater." Journal of Mining and Earth Sciences 61, no. 5 (October 31, 2020): 135–44. http://dx.doi.org/10.46326/jmes.2020.61(5).15.

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Four types of biochar material synthesized from spent coffee grounds by slow pyrolysis process CF1 (500(C/0.5h); CF2 (500(C/1.5h); CF3 (500(C/3h); CF4 (500(C/6h) is studied to treat two pollution parameters (COD and TSS) in livestock wastewater. Material characteristics were determined by SEM, EDX and BET methods. The results showed that the 4 samples of biochar materials were structured fiber clearly, the interplanar spacing which corresponds to the lattice plane. The C content in the biochar sample is higher than the initial raw material sample; the highest value recorded reaches 90.61% C (CF2). 100 mL of the original livestock waster water is filtered through columns with 4g of biochar CF1-CF4 during reaction times varied from 0h, 1h, 4h and 8h, the COD treatment efficiency and adsorption content of CF4 sample is highest of 96.41% and 188 mg/g after 8h, and the lowest value is 76.67% and 149.5 mg/g after 1h recorded in CF3 sample, however the COD value after treatment is still higher from 1.2 to 1.46 times than Vietnamese standard 62: 2016/MONRE - national technical regulation on the effluent of livestock. The CF3 material samples have the highest TSS treatment efficiency and adsorption content of 95.19% and 6.425 mg/g after 8h and the lowest of 66.78% and 4.575 mg/g recorded in CF1 samples after 1h, response the requirements of QCVN 62: 2016/MONRE. The results showed that biochar is a potential sorbent to removed pollutants from waste water.

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4

Suga, N., and K. Tsuzuki. "Inhibition and level-tolerant frequency tuning in the auditory cortex of the mustached bat." Journal of Neurophysiology 53, no. 4 (April 1, 1985): 1109–45. http://dx.doi.org/10.1152/jn.1985.53.4.1109.

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For echolocation the mustached bat, Pteronotus parnellii, emits complex orientation sounds (pulses), each consisting of four harmonics with long constant-frequency components (CF1-4) followed by short frequency-modulated components (FM1-4). The CF signals are best suited for target detection and measurement of target velocity. The CF/CF area of the auditory cortex of this species contains neurons sensitive to pulse-echo pairs. These CF/CF combination-sensitive neurons extract velocity information from Doppler-shifted echoes. In this study we electrophysiologically investigated the frequency tuning of CF/CF neurons for excitation, facilitation, and inhibition. CF1/CF2 and CF1/CF3 combination-sensitive neurons responded poorly to individual signal elements in pulse-echo pairs but showed strong facilitation of responses to pulse-echo pairs. The essential components in the pairs were CF1 of the pulse and CF2 or CF3 of the echo. In 68% of CF/CF neurons, the frequency-tuning curves for facilitation were extremely sharp for CF2 or CF3 and were "level-tolerant" so that the bandwidths of the tuning curves were less than 5.0% of best frequencies even at high stimulus levels. Facilitative tuning curves for CF1 were level tolerant only in 6% of the neurons studied. CF/CF neurons were specialized for fine analysis of the frequency relationship between two CF sounds regardless of sound pressure levels. Some CF/CF neurons responded to single-tone stimuli. Frequency-tuning curves for excitation (responses to single-tone stimuli) were extremely sharp and level tolerant for CF2 or CF3 in 59% of CF1/CF2 neurons and 70% of CF1/CF3 neurons. Tuning to CF1 was level tolerant in only 9% of these neurons. Sharp level-tolerant tuning may be the neural basis for small difference limens in frequency at high stimulus levels. Sharp level-tolerant tuning curves were sandwiched between broad inhibitory areas. Best frequencies for inhibition were slightly higher or lower than the best frequencies for facilitation and excitation. We thus conclude that sharp level-tolerant tuning curves are produced by inhibition. The extent to which neural sharpening occurred differed among groups of neurons tuned to different frequencies. The more important the frequency analysis of a particular component in biosonar signals, the more pronounced the neural sharpening. This was in addition to the peripheral specialization for fine frequency analysis of that component. The difference in bandwidth or quality factor between the excitatory tuning curves of peripheral neurons and the facilitative and excitatory tuning curves of CF/CF neurons was larger at higher stimulus levels.(ABSTRACT TRUNCATED AT 400 WORDS)

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5

O'Hagan, David, Yi Wang, Maciej Skibinski, and Alexandra M. Z. Slawin. "Influence of the difluoromethylene group (CF2) on the conformation and properties of selected organic compounds." Pure and Applied Chemistry 84, no. 7 (April 7, 2012): 1587–95. http://dx.doi.org/10.1351/pac-con-11-09-26.

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The CF2 group has found applications as a substituent in all classes of organic chemical products from medicinal products to materials, although it is less frequently encountered than the C–F and CF3 substituents. In this review, the geometric influence of placing two fluorine atoms on carbon is considered and in particular, deviations from tetrahedral geometry are noted. The incorporation of the CF2 group into CF2 phosphonates as phosphate mimics is reviewed and the geometric and steric influences of the CF2 group are considered when the substituent is placed within aliphatic chains and aliphatic ring (cyclododecane) systems.

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6

Jeffries, Benjamin, Zhong Wang, Jérôme Graton, Simon D. Holland, Thomasin Brind, Ryan D. R. Greenwood, Jean-Yves Le Questel, James S. Scott, Elisabetta Chiarparin, and Bruno Linclau. "Reducing the Lipophilicity of Perfluoroalkyl Groups by CF2–F/CF2–Me or CF3/CH3 Exchange." Journal of Medicinal Chemistry 61, no. 23 (November 9, 2018): 10602–18. http://dx.doi.org/10.1021/acs.jmedchem.8b01222.

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7

Sambol, Susan P., Michelle M. Merrigan, David Lyerly, Dale N. Gerding, and Stuart Johnson. "Toxin Gene Analysis of a Variant Strain ofClostridium difficile That Causes Human Clinical Disease." Infection and Immunity 68, no. 10 (October 1, 2000): 5480–87. http://dx.doi.org/10.1128/iai.68.10.5480-5487.2000.

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ABSTRACT A toxin variant strain of Clostridium difficile was isolated from two patients with C. difficile-associated disease (CDAD), one of whom died from extensive pseudomembranous colitis. This strain, identified by restriction endonuclease analysis (REA) as type CF2, was not detected by an immunoassay for C. difficile toxin A. Culture supernatants of CF2 failed to elicit significant enterotoxic activity in the rabbit ileal loop assay but did produce atypical cytopathic effects in cell culture assay. Southern hybridization, PCR amplification, and DNA sequence analyses were performed on the toxin A (tcdA) and toxin B (tcdB) genes of type CF2 isolate 5340. Type CF2 5340tcdA exhibited a 1,821-bp truncation, due to three deletions in the 3′ end of the gene, and a point mutation in the 5′ end of the gene, resulting in a premature stop codon at tcdAposition 139. Type CF2 5340 tcdB exhibited multiple nucleotide base substitutions in the 5′ end of the gene compared totcdB of the standard toxigenic strain VPI 10463. Type CF2 5340 toxin gene nucleotide sequences and deduced amino acid sequences showed a strong resemblance to those of the previously described variant C. difficile strain 1470, a strain reported to have reduced pathogenicity and no association with clinical illness in humans. REA of strain 1470 identified this strain as a distinct type (CF1) within the same REA group as the closely related type CF2. A review of our clinical-isolate collection identified five additional patients infected with type CF2, three of whom had documented CDAD. PCR amplification of the 3′ end of tcdA demonstrated identical 1.8-kb deletions in all seven type CF2 isolates. REA type CF2 is a toxin variant strain of C. difficile that retains the ability to cause disease in humans but is not detected in clinical immunoassays for toxin A.

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8

Wlassics, Ivan, and Vito Tortelli. "Coupling Reactions of Chlorofluoro and Perfluoroalkyl Iodides." Collection of Czechoslovak Chemical Communications 73, no. 12 (2008): 1719–28. http://dx.doi.org/10.1135/cccc20081719.

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Coupling reactions of chlorofluoro- and perfluoroalkyl iodides Rf-I with Rf = ClCF2CFCl(CF2)3CF2-, ClCF2CFClO(CF2)3CF2-, ClCF2CFCl-, (CF3)2CF- , (CF3)2CFCF2CF2- in the presence of a zinc/solvent system give dimers in good yields. Both homodimerizations (one iodide) and heterodimerizations (two different iodides) have been studied. The effect of temperature and solvent is shown. The zinc mediated dechlorination of vicinal chlorine atoms in the dimers afforded terminal alkenes and dienes.

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9

Riquimaroux, H., S. J. Gaioni, and N. Suga. "Inactivation of the DSCF area of the auditory cortex with muscimol disrupts frequency discrimination in the mustached bat." Journal of Neurophysiology 68, no. 5 (November 1, 1992): 1613–23. http://dx.doi.org/10.1152/jn.1992.68.5.1613.

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1. The Jamaican mustached bat uses a biosonar signal (pulse) with eight major components: four harmonics each consisting of a long constant frequency (CF1-4) component followed by a short frequency-modulated (FM1-4) component. While flying, the bat adjusts the frequency of its pulse so as to maintain the CF2 of the Doppler-shifted echo at a frequency to which its cochlea is very sharply tuned. This Doppler shift (DS) compensation likely is mediated or influenced by the Doppler-shifted CF (DSCF) processing area of the primary auditory cortex, which only represents frequencies in the range of echo CF2s (60.6 to 62.3 kHz when the "resting" frequency of the CF2 is 61.0 kHz). 2. We trained four bats to discriminate between different trains of paired tone bursts that mimicked a bat's pulse CF2 and the accompanying echo CF2. The frequency of these CF2s ranged between 61.0 and 64.0 kHz. A discriminated shock avoidance procedure response was employed using a leg flexion. For one stimulus, the S+, the pulse and echo CF2s were the same frequency (delta f = 0, i.e., no Doppler shift). A leg flexion during the S+ turned off both the S+ and the scheduled shock. For a second stimulus, the S-, the echo CF2 was 0.05, 0.1, 0.3, 0.5, or 2.0 kHz higher than the pulse CF2. A delta f of 0.05 kHz was a frequency difference of 0.08%. No shock followed the S-, and leg flexions had no consequences. Correct responses consisted of a leg flexion during the S+ and no flexion during the S-; these responses were added together to compute the percentage of correct responses. When a bat correctly responded at better than 75% for all the delta f s, muscimol, a potent agonist of gamma-aminobutyric acid, was bilaterally applied to inactivate the DSCF area. Performance on each delta f discrimination was then measured. 3. Initial attempts to condition the bats to flex their legs to the CF tones mimicking part of the natural pulses and echoes failed. When broad-band noise bursts were substituted, however, the conditioned response was rapidly established. The noise band-width was gradually reduced and then replaced with the CF tones. Discrimination training with the tone burst trains then commenced. Throughout this procedure, the bats maintained their responding to the stimuli. The bats typically required approximately 20-30 sessions to perform consistently (> or = 75% correct responses) a discrimination involving a 2 kHz delta f.(ABSTRACT TRUNCATED AT 400 WORDS)

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10

Minkwitz, R., and D. Lamek. "Darstellung der Iminiumsalze CF3?NX?CF2+MF6? (X = CH3, F und M = As, Sb) und CF3?NCl = CF2+ AsF6?" Zeitschrift f�r anorganische und allgemeine Chemie 620, no. 3 (March 1994): 514–18. http://dx.doi.org/10.1002/zaac.19946200320.

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11

Van De Grampel, Robert D., Jan Van Geldrop, Jozua Laven, and Rob Van Der Linde. "P[CF3(CF2)5CH2MA-co-MMA] and P[CF3(CF2)5CH2MA-co-BA] copolymers: Reactivity ratios and surface properties." Journal of Applied Polymer Science 79, no. 1 (2000): 159–65. http://dx.doi.org/10.1002/1097-4628(20010103)79:1<159::aid-app180>3.0.co;2-w.

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12

Normant, Jean-F. "Synthesis of selectivity fluorinated substrates via organometallic reagents derived from CF2CFCl, CF2CCl2, CF2CH2." Journal of Organometallic Chemistry 400, no. 1-2 (December 1990): 19–34. http://dx.doi.org/10.1016/0022-328x(90)83003-3.

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13

Dixon, David A., and David Feller. "Heats of Formation of CF2, FCO, and CF2O." Journal of Physical Chemistry A 102, no. 42 (October 1998): 8209–16. http://dx.doi.org/10.1021/jp982655g.

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14

Vater, M., M. Kössl, E. Foeller, F. Coro, E. Mora, and I. J. Russell. "Development of Echolocation Calls in the Mustached Bat, Pteronotus parnellii." Journal of Neurophysiology 90, no. 4 (October 2003): 2274–90. http://dx.doi.org/10.1152/jn.00101.2003.

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Adult mustached bats employ Doppler-sensitive sonar to hunt fluttering prey insects in acoustically cluttered habitats. The echolocation call consists of 4–5 harmonics, each composed of a long constant frequency (CF) component flanked by brief frequency modulations (FM). The 2nd harmonic CF component (CF2) at 61 kHz is the most intense, and analyzed by an exceptionally sharply tuned auditory system. The maturation of echolocation calls and the development of Doppler-shift compensation was studied in Cuba where large maternity colonies are found in hot caves. In the 1st postnatal week, infant bats did not echolocate spontaneously but could be induced to vocalize CF-FM signals by passive body motion. The CF2 frequency emitted by the smallest specimens was at 48 kHz (i.e., 0.4 octaves lower than the adult signal). CF-FM signals were spontaneously produced in the 2nd postnatal week at a CF2 frequency of 52 kHz. The CF2 frequencies of induced and spontaneous calls shifted upward to reach a value of 60.5 kHz in the 5th postnatal week. Standard deviations of CF2 frequency were large (up to ±1.5 kHz) in the youngest bats and dropped to values of ±250 Hz at the end of the 3rd postnatal week. Some individuals in the 4th and 5th postnatal weeks emitted with adultlike frequency precision of about ±100 Hz. In the youngest bats, the 1st harmonic CF component (CF1) was up to 22 dB stronger than CF2. Adultlike relative levels of CF1 (–28 dB relative to CF2) were reached in the 5th postnatal week. In spontaneously emitted CF-FM calls, the duration of the CF2 component gradually increased with age from 5 ms to maximum values of 18 ms. Durations of the CF2 component in induced calls averaged 7 ± 2.6 ms in the 1st postnatal week and 8.2 ± 1.5 ms in the 5th postnatal week. There were no age-related changes in duration of the terminal FM sweep (3 ± 0.4 ms) in both induced and spontaneous calls. The magnitude of the terminal FM sweep in spontaneous calls was not correlated with age (mean 13.5 ± 2 kHz). Values for induced calls slightly increased with age from 11 ± 2 to 13 ± 2 kHz. The emission rate of induced CF-FM signals increased with age from values of 2.5 ± 2 to 17 ± 5 pulses/s. Values for spontaneously emitted calls were 4.4 ± 3 and 9 ± 4.5 pulses/s, respectively. Doppler-shift compensation, as tested in the pendulum task, emerged during the 4th postnatal week in young bats that were capable of very brief active flights, but before the time of active foraging outside the cave.

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15

Schulze, Wolfgang, Hans Hartl, and Konrad Seppelt. "CF2-verbrückte Metallkomplexe." Angewandte Chemie 98, no. 2 (February 1986): 189–90. http://dx.doi.org/10.1002/ange.19860980225.

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16

Su, Debao, Wenbiao Cen, Robert L. Kirchmeier, and Jean'ne M. Shreeve. "Synthesis of fluorinated phosphonic, sulfonic, and mixed phosphonic/sulfonic acids." Canadian Journal of Chemistry 67, no. 11 (November 1, 1989): 1795–99. http://dx.doi.org/10.1139/v89-278.

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The acids (HO)2P(O)CFHSO3H, (HO)2P(O)(CF2)4O(CF2)2SO3H, H(CF2)2O(CF2)2P(O)(OH)2, H(CF2)2O(CF2)4P(O)(OH)2, (HO)2P(O)(CF2)2O(CF2)4H, and the acid precursor (C2H5O)2P(O)CF(SO3Na)2 have been synthesized. Elemental analysis, 19F, 1H, and 31P NMR, and mass spectroscopy were used for characterization of these materials. They are very strong acids, and exhibit a high degree of stability in aqueous solution at elevated temperature, which makes them attractive candidates for use as electrolytes in fuel cells. Keywords: fluorinated phosphonic acids; fluorinated sulfonic acids; 1H, 19F, 31P NMR.

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17

Gentzrsch, A., H. Wessolowski, and G. V. Röschenthaler. "SF5CFCF2 and CF3CFCF2 in phosphorus chemistry: a comparison." Journal of Fluorine Chemistry 54, no. 1-3 (September 1991): 56. http://dx.doi.org/10.1016/s0022-1139(00)83566-6.

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18

NORMANT, J. F. "ChemInform Abstract: Synthesis of Selectively Fluorinated Substrates via Organometallic Reagents Derived from CF2=CFCl, CF2=CCl2, CF2=CH2." ChemInform 22, no. 13 (September 1, 2010): no. http://dx.doi.org/10.1002/chin.199113305.

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19

Grobe, Joseph, Duc Le Van, and Jürgen Nientiedt. "Reaktive E = C (p—p) π -Systeme, XI. Hydrometallierungsreaktionen des Perfluor-2-phosphapropens F3CP = CF2/ Reactive E = C (p —p) π -Systems, XI. Hydrometallation Reactions of Perfluoro-2-phosphapropene F3CP = CF2." Zeitschrift für Naturforschung B 42, no. 8 (August 1, 1987): 984–92. http://dx.doi.org/10.1515/znb-1987-0810.

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AbstractThe reactions of F3CP = CF2 (1) with Me3GeH, Me3SnH, and (C5R5)(CO)3MH (M = Cr. Mo, W; R = H , Me) proceed via addition to the PC double bond yielding tertiary phosphanes of the type Me3M′P(CF3)CF2H[M′ = Ge (2), Sn (3)] or (C5R5)(CO)3MP(CF3)CF2H [R = H; M - Cr (6), Mo (7). W (8); R = Me; M = Mo (9), W (10)]. 2 and 3 are labile compounds, which decompose by elimination of Me3M′F , a reaction which in the case of 3 has been used to prepare the new phosphaalkene F3CP = C(H)F (5) and its [2+4]-cycloaddition product 4 with 2.3-dimethyl-1.3- butadiene. The H substituent (instead of F) in 5 and its derivatives has a surprising influence not only on the stability of the compounds but also on their spectroscopic data, as shown by com parison with 1 and derivatives of the type Me3M ′P(CF3)2 and (C5H5)(CO)3MP(CF3)2. respectively. New compounds are characterized by NMR, MS. GC/MS and IR measurements.

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20

FUJIOKA, Hiroyuki, Souichi MASHINO, Satoshi AIKYO, Miki GOTO, and Toshihiko ARAI. "Measurement of CF3 and CF2 Radical Densities in a Hollow Cathode DC CF4 Plasma." SHINKU 42, no. 7 (1999): 647–51. http://dx.doi.org/10.3131/jvsj.42.647.

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21

Dornhöfer, G., W. Hack, K. Hoyermann, and G. Rohde. "Elementary Processes of CF2(Ā1B1) and CF2(X̄1A1) with Reactive Gases." Berichte der Bunsengesellschaft für physikalische Chemie 94, no. 4 (April 1990): 468–74. http://dx.doi.org/10.1002/bbpc.19900940410.

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22

Oliete, P. B., V. M. Orera, and P. J. Alonso. "EPR of jahn-teller Cf2+in CaF2, BaF2and SrC12." Radiation Effects and Defects in Solids 135, no. 1-4 (December 1995): 179–82. http://dx.doi.org/10.1080/10420159508229830.

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23

Lin, Jyh Shing, Shao-Yu Lu, and Wen-Chi Chou. "DFT study of self-coupling reaction of CF2(ads) coadsorbed on Cu(111) surface for forming CF2=CF2(g)." Surface Science 605, no. 1-2 (January 2011): 131–37. http://dx.doi.org/10.1016/j.susc.2010.10.010.

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24

Zhang, Rui, Bing Li, Dai Xian Zhang, Fan Zhang, and Jian Jun Wu. "Chemical Structure of Fluorocarbon Films Deposited by Pulsed Plasma Thruster." Advanced Materials Research 602-604 (December 2012): 1465–69. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.1465.

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Fluorocarbon films were deposited using a Pulsed Plasma Thruster. By means of mass spectrum analysis, the compositions of the Pulsed Plasma Thruster plume were studied. The microstructure and chemical bonding nature of the films were investigated by X-ray photoelectron spectroscopy. The plume consists primarily of C, F, CF, CF2, CF3, amounts of thruster body materials are detected as well. Five chemical bonds, CF3, CF2, CF, C-CFx, and elemental carbon bonds are observed on the surface of all the deposited films, the content of the various chemical bonds change with deposited angle, the F/C ratio reaches a minimum value of 0.7643 at 15 degree, and increases gradually with deposited angle increasing from 15 degree to 60 degree.

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25

Eger, Edmond I., Pompiliu Ionescu, Michael J. Laster, Diane Gong, Richard B. Weiskopf, and Russell L. Kerschmann. "Quantitative Differences in the Production and Toxicity of CF2=BrCl Versus CH2 F-O-C(=CF2)(CF3) (Compound A)." Anesthesia & Analgesia 85, no. 5 (November 1997): 1164–70. http://dx.doi.org/10.1097/00000539-199711000-00037.

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26

Eger, Edmond I., Pompiliu Ionescu, Michael J. Laster, Diane Gong, Richard B. Weiskopf, and Russell L. Kerschmann. "Quantitative Differences in the Production and Toxicity of CF2=BrCl Versus CH2 F-O-C(=CF2)(CF3) (Compound A)." Anesthesia & Analgesia 85, no. 5 (November 1997): 1164–70. http://dx.doi.org/10.1213/00000539-199711000-00037.

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27

Kamakshi, T., and G. Sunita Sundari. "Photocatalytic Degradation of Methylene Blue via Cobalt Doped Fe3O4 Nanoparticles." Asian Journal of Chemistry 32, no. 6 (2020): 1413–20. http://dx.doi.org/10.14233/ajchem.2020.22621.

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Cobalt doped Fe3O4 i.e., CoFe3O4 nanoparticles of different concentrations (0, 0.5, 1.0, 1.5, 2.0, 2.5 mol% were represented as Fe3O4, CF1, CF2, CF3, CF4, CF5, respectively) were synthesized using a chemical co-precipitation technique. The XRD patterns and FTIR spectra of Co doped Fe3O4 revealed the formation of spinel structure indicating the successful incorporation of cobalt ions with the Fe3O4 structure of the iron ions at octahedral sites. Scanning electron micrographs showed a fine uniform spherical particles. UV spectroscopic analysis showed that cobalt doping in CoFe3O4 nanocomposites influenced the band gap values. These band gap values decreased in the range of 2.76-1.61 eV (direct), 2.53-0.97 eV (indirect) with increase of cobalt content. The activity of CoFe3O4 in photocatalysis was investigated using methylene blue azo dye under visible light. These results depicted that for 1% cobalt doped Fe3O4 novel material photocatalytic activity was enhanced than all other prepared nanomaterials.

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Schulze, Wolfgang, Hans Hartl, and Konrad Seppelt. "CF2-Bridged Metal Complexes." Angewandte Chemie International Edition in English 25, no. 2 (February 1986): 185–87. http://dx.doi.org/10.1002/anie.198601851.

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Cobos, C. J., A. E. Croce, K. Luther, L. Sölter, E. Tellbach, and J. Troe. "Experimental and Modeling Study of the Reaction C2F4 (+ M) ⇔ CF2 + CF2 (+ M)." Journal of Physical Chemistry A 117, no. 45 (October 31, 2013): 11420–29. http://dx.doi.org/10.1021/jp408363s.

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30

McKean, Donald C., Mark M. Law, Peter Groner, Andrew R. Conrad, Michael J. Tubergen, David Feller, Michael C. Moore, and Norman C. Craig. "Infrared Spectra of CF2═CHD and CF2═CD2: Scaled Quantum-Chemical Force Fields and an Equilibrium Structure for 1,1-Difluoroethylene." Journal of Physical Chemistry A 114, no. 34 (September 2, 2010): 9309–18. http://dx.doi.org/10.1021/jp104498n.

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31

Bailey, W. C., R. K. Bohn, C. T. Dewberry, G. S. Grubbs, and S. A. Cooke. "The structure and helicity of perfluorooctanonitrile, CF3–(CF2)6–CN." Journal of Molecular Spectroscopy 270, no. 1 (November 2011): 61–65. http://dx.doi.org/10.1016/j.jms.2011.09.001.

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32

Morris, Robert A., A. A. Viggiano, and John F. Paulson. "Reactions of CF+, CF2+, and CF3+ with Perfluorobuta-1,3-diene." Journal of Physical Chemistry 98, no. 14 (April 1994): 3564–65. http://dx.doi.org/10.1021/j100065a003.

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33

Cobos, C. J., G. Knight, L. Sölter, E. Tellbach, and J. Troe. "Falloff Curves of the Reaction CF3 (+M) → CF2 + F (+M)." Journal of Physical Chemistry A 124, no. 7 (January 24, 2020): 1235–39. http://dx.doi.org/10.1021/acs.jpca.9b10393.

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34

Grobe, Joseph, Gudrun Lange, and Duc Le Van. "Reaktive E=C(p – p) π-Systeme, XXI [1] / Reactive E=C(p – p)π-Systems, XXI [1]." Zeitschrift für Naturforschung B 45, no. 3 (March 1, 1990): 299–307. http://dx.doi.org/10.1515/znb-1990-0305.

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1λ3,3λ3-Diphosphanes of the type R2PCF2P(H)CF3 [R = Me (3), Et (5), Cyclohexyl (6), Ph (7)] are formed in acceptable yields (40-75%) by reacting perfluoro-2-phosphapropene F3CP=CF2 (1) with the corresponding secondary phosphanes R2PH. By reaction with sulfur, compounds 3, 5 and 7 selectively yield the corresponding monosulfur derivates R2P(S)CF2P(H)CF3 [R = Me (8), Et (9), Ph (10)]. Treatment of 3 or 7 with dimethylamine (molar ratio 1/2) leads via HF elimination and addition of Me2NH to the aminophosphanes R2PCHFP(NMe2)CF3 [R = Me (11), Ph (12)]. In a similar procedure HF has been eliminated from 3 by 1,4-diazabicyclo[2.2.2]octane (DABCO), and on addition of methanol or ethanol to the 1,3-diphosphapropene intermediate, the alkoxy compounds Me2PCHFP(OR)CF3 [R = Me (13), Et (14)] have been obtained.

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35

Bhatt, Pankaj, Wenping Zhang, Ziqiu Lin, Shimei Pang, Yaohua Huang, and Shaohua Chen. "Biodegradation of Allethrin by a Novel Fungus Fusarium proliferatum Strain CF2, Isolated from Contaminated Soils." Microorganisms 8, no. 4 (April 20, 2020): 593. http://dx.doi.org/10.3390/microorganisms8040593.

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Continuous use of allethrin has resulted in heavy environmental contamination and has raised public concern about its impact on human health, yet little is known about the kinetics and microbial degradation of this pesticide. This study reported the degradation kinetics in a novel fungal strain, Fusarium proliferatum CF2, isolated from contaminated agricultural fields. Strain CF2 utilized 50 mg·L−1 of allethrin as the sole carbon source for growth in minimal salt medium and tolerated high concentrations of allethrin of up to 1000 mg·L−1. The optimum degradation conditions for strain CF2 were determined to be a temperature of 26 °C and pH 6.0 using response surface methodology. Under optimum conditions, strain CF2 completely degraded allethrin within 144 hours. The degradation kinetics of allethrin followed first order reaction kinetics. Kinetics analysis showed that its half-life was substantially reduced by 507.1 hours, as compared to the uninoculated control. This study provides new insights into the microbial degradation of allethrin with fungal F. proliferatum CF2.

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36

Knachel, Howard C., Vladimir Benin, William E. Moddeman, Janine C. Birkbeck, Thomas A. Kestner, and Tanya L. Young. "Characterization by NMR of reactants and products of hydrofluoroether isomers, CF3 (CF2 )3 OCH3 and (CF3 )2 C(F)CF2 OCH3 , reacting with isopropyl alcohol." Magnetic Resonance in Chemistry 51, no. 7 (May 23, 2013): 407–13. http://dx.doi.org/10.1002/mrc.3964.

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37

Gaggl, S. A., and S. Woltran. "The cf2 argumentation semantics revisited." Journal of Logic and Computation 23, no. 5 (April 26, 2012): 925–49. http://dx.doi.org/10.1093/logcom/exs011.

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38

Ben Salha, Herrera Díaz, Lengliz, Abderrabba, and Labidi. "Effect of the Chemical Composition of Free-Terpene Hydrocarbons Essential Oils on Antifungal Activity." Molecules 24, no. 19 (September 29, 2019): 3532. http://dx.doi.org/10.3390/molecules24193532.

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In this study, Carum carvi L. essential oil (CEO) and Origanum majorana L. essential oil (MEO) was steam-distillated under reduced pressure. We henceforth obtained three fractions for each essential oil: CF1, CF2, CF3, MF1, MF2, and MF3. Then, these fractions were characterized using the gas chromatography–mass spectrometry (GC-MS) technique. The results indicated that some fractions were rich in oxygenated compounds (i.e., CF2, CF3, MF2, and MF3) with concentrations ranging from 79.21% to 98.56%. Therefore, the influence of the chemical composition of the essential oils on their antifungal activity was studied. For this purpose, three food spoilage fungi were isolated, identified, and inoculated in vitro, in order to measure the antifungal activity of CEO, MEO, and their fractions. The results showed that stronger fungi growth inhibitions (FGI) (above 95%) were found in fractions with higher percentages of oxygenated compounds, especially with (−)-carvone and terpin-4-ol as the major components. Firstly, this work reveals that the free-terpenes hydrocarbons fractions obtained from MEO present higher antifungal activity than the raw essential oil against two families of fungi. Then, it suggests that the isolation of (−)-carvone (97.15 ± 5.97%) from CEO via vacuum distillation can be employed successfully to improve antifungal activity by killing fungi (FGI = 100%). This study highlights that separation under reduced pressure is a simple green method to obtain fractions or to isolate compounds with higher biological activity useful for pharmaceutical products or natural additives in formulations.

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39

Zhang, X. Y., J. Hu, H. Y. Zhou, J. J. Hao, Y. F. Xue, H. Chen, and B. G. Wang. "First Report of Fusarium oxysporum and F. solani Causing Fusarium Dry Rot of Carrot in China." Plant Disease 98, no. 9 (September 2014): 1273. http://dx.doi.org/10.1094/pdis-02-14-0156-pdn.

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Carrot (Daucus carota L.) is an economically important vegetable crop in China. In August 2008, a disease was observed on carrot in Inner Mongolia. The symptoms appeared as dry rot lesions on root surface, expressing light brown cankers with defined rounded or irregular shapes (1,3). The average disease incidence was up to 80% in Tuo Ke Tuo County. The disease has been a serious problem in these two counties since then, especially where consecutive carrot cropping was practiced. Carrot roots with typical dry rot symptoms were washed with tap water. Root tissues near the margin of necrotic lesions were excised, surface sterilized with 1% NaOCl for 3 min, and rinsed with sterile distilled water three times. The disinfected tissue was placed on potato dextrose agar (PDA) in a petri dish. Plates were incubated at 25 ± 1°C in the dark for 4 days. Fusarium single spore isolates were obtained from characteristic colonies (1). Three isolates (CF1, CF2, and CF3) were used for further study. The isolates were identified as Fusarium spp. on the basis of microscopic morphology on PDA. CF1 produced pink pigment, abundant falciform macroconidia of 14.7 to 38.2 × 4.5 to 5.7 μm with 2 to 3 septates, and elliptic microconidia of 7.5 to 15.1 × 3.3 to 5.4 μm with none or one septate. CF2 and CF3 produced light blue pigment, abundant falciform macroconidia of 16.4 to 34.4 × 4.0 to 6.1 μm with 2 to 3 septates, and elliptic microconidia of 6.7 to 10.7 × 3.0 to 4.9 μm with none or one septate. They were further identified and confirmed by PCR. The PCR involved amplifying the internal transcribed spacer (ITS) region of ribosomal DNA using genomic DNA as the template with universal primers ITS1 and ITS4 (2). The PCR products were sequenced. BLAST analysis of these sequences against the GenBank database determined the taxonomy of the isolates. The sequence of CF1 was 99% identical to F. oxysporum (Accession No. KC594035); sequences of CF2 and CF3 were 99% identical to F. solani (KC215123). To confirm the pathogenicity of the isolates, mature carrot roots (cv. Hong Ying 2) were inoculated with mycelial plugs (5 mm in diameter) cut from the margin of actively growing colonies on PDA plates. One mycelial plug was placed on each carrot root, with the mycelial side facing the root. PDA plugs were used for controls. Each treatment had five replicates. The inoculated roots were incubated in a humid chamber (90% RH) at 25°C. Four days after incubation, mycelia of the isolates developed and covered most of the surface of carrot roots, and brown rot lesions were observed on all inoculated roots, while the controls remained symptomless. This experiment was repeated. In another trial, carrot seeds (cv. Hong Ying 2) were sown in sterilized soil in pots (30 × 25 cm opening) with 15 seeds per pot. The soil was infested with either CF1, CF2, or CF3 by adding spore suspension to make the final concentration of 1 × 104 CFU/g soil. Plants grown in non-infested soil served as controls. There were three replicates per treatment. All the treated pots were placed in a field. After 13 weeks, the same symptoms of dry rot were observed as previously described. No symptoms were observed on the control plants. The trial was repeated. Symptomatic tissues from the inoculated roots were sampled and the pathogen was re-isolated, and identified using PCR. To our knowledge, this is the first report of F. oxysporum and F. solani causing dry rot of carrot in China. References: (1) H. Abe et al. Annual Report of the Society of Plant Protection of North Japan, 48:106-108, 1997. (2) X. Lu. Plant Dis. 97:991, 2013. (3) A. F. Sherf and A. MacNab. Pages 138-139 in: Vegetable Diseases and Their Control. John Wiley & Sons, Inc., 1986.

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40

Lehmler, Hans-Joachim, Sean Parkin, and Carolyn Pratt Brock. "Packing conflicts in the Z′ = 5 structure of CF3(CF2)3(CH2)10COOH." Acta Crystallographica Section B Structural Science 60, no. 3 (May 17, 2004): 325–32. http://dx.doi.org/10.1107/s0108768104005609.

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Dimers of the partially fluorinated amphiphile 1-(perfluorobutyl)undecanoic acid, CF3(CF2)3(CH2)10COOH, crystallize in the same basic packing arrangement found for many n-alkyl carboxylic acids. The unit cell of the fluorinated compound, however, contains five independent molecules rather than the one found for most n-alkyl carboxylic acids including CH3(CH2)13COOH. The structures of the two C15 acids are compared. The structural modulations that lead to the large value of Z′ can be understood as resulting from the conflict between the necessity of filling space densely and uniformly and the tendency of unlike groups to be segregated spatially. The few other known structures of compounds with both (CF2) n and (CH2) m regions show evidence of the same conflict.

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41

Wang, Wei, Pingyang Wang, Qian Zhang, Pengcheng Du, Jianhua Zhang, Hongmei Deng, and Haizhen Jiang. "Construction of S-CF2/ O-CF2 bonds via inter/intramolecular radical nucleophilic substitution reaction." Tetrahedron 76, no. 38 (September 2020): 131477. http://dx.doi.org/10.1016/j.tet.2020.131477.

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42

Tokuhashi, Kazuaki, Akifumi Takahashi, Masahiro Kaise, Shigeo Kondo, Akira Sekiya, and Etsuo Fujimoto. "Rate constants for the reactions of OH radicals with CF3OCF=CF2 and CF3CF=CF2." Chemical Physics Letters 325, no. 1-3 (July 2000): 189–95. http://dx.doi.org/10.1016/s0009-2614(00)00626-6.

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43

Acero, Anibal A., Mengyang Li, Binhua Lin, Stuart A. Rice, Michel Goldmann, Issam Ben Azouz, Anne Goudot, and Francis Rondelez. "Molecular packing in water supported monolayers of F(CF2)11COOH and F(CF2)10CH2COOH." Journal of Chemical Physics 99, no. 9 (November 1993): 7214–20. http://dx.doi.org/10.1063/1.465438.

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44

Grobe, Joseph, Duc Le Van, and Jürgen Nientiedt. "Reaktive E=C(p-p)π-Systeme, VI [1] Reaktionen des Phosphaalkens F3CP=CF2 mit H-aciden Verbindungen/Reactive E = C(p-p)π-Systems, VI [1] Reactions of the Phosphaalkene F3CP = CF2 with H Acidic Compounds." Zeitschrift für Naturforschung B 41, no. 2 (February 1, 1986): 149–61. http://dx.doi.org/10.1515/znb-1986-0203.

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The reactions o f the perfluorophosphaalkene F3CP = CF2 (1) with HX compounds proceed via addition to the PC double bond yielding either secondary phosphanes F3CP(H)CF2X (X = OH, OR, NR2, PMe2) or PX derivatives F3CP(X)CF2H (X = Cl, Br, SMe, SeMe, AsMe2). The rate of reaction with H2O is strongly pH-dependent, but only at pH > 13 the opposite direction of addition is observed. Similar results are obtained for the addition of alcohols, for which the presence of OR- results in two effects: (i) Reversion of the addition direction to yield F3CP(OR)CF2H; (ii) HF elimination from F3CP(H)CF2OR to give substituted phosphaalkenes. With strong bases HNR2, the addition is followed immediately by HF elimination producing the surprisingly stable phosphaalkenes F3CP = C(F)NR2 (R = Me, Et). Secondary phosphanes of the type F3CP(H)CF2X (X = OMe, OEt, PMe2) are found to be suitable precursors for the preparation of novel heterosubstituted derivatives of 1 by elimination of HF with NMe3. New compounds were characterized by NMR, MS, GC/MS and GC/IR measurements.

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45

Kysilka, Ondřej, Markéta Rybáčková, Martin Skalický, Magdalena Kvíčalová, Josef Cvačka, and Jaroslav Kvíčala. "HFPO Trimer-Based Alkyl Triflate, a Novel Building Block for Fluorous Chemistry. Preparation, Reactions and 19F gCOSY Analysis." Collection of Czechoslovak Chemical Communications 73, no. 12 (2008): 1799–813. http://dx.doi.org/10.1135/cccc20081799.

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Triflate 4, CF3(CF2)2O-CF(CF3)CF2O-CF(CF3)CH2-OTf (RFOCH2OTf), of the HFPO trimer-based alcohol 3 (RFOCH2OH) is a novel highly fluorinated building block for fluorous chemistry. In analogy to similar polyfluorinated triflates with methylene spacer, its reactivity is limited to strong and soft nucleophiles. Whereas reactions with cyanide anion, phenolate anion, enolate of diethyl malonate or lithium salt of benzaldehyde bis(phenylsulfanyl)acetal were unsuccessful, the corresponding imidazole 5, iodide 6 or azide 7 were prepared in good yields. Reaction of imidazole 5 with (perfluorohexyl)methyl triflate (9) afforded highly fluorinated non-crystalline imidazolium salt 8, TfO-RFOCH2-(C3H3N2)+-CH2C6F13-n, which could be employed as fluorous ionic liquid or intermediate for fluorous carbenes. Complete assignment of complex 19F NMR spectra of all compounds employed was accomplished using 19F gCOSY NMR method.

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46

Srinivasan, N. K., M. C. Su, J. V. Michael, A. W. Jasper, S. J. Klippenstein, and L. B. Harding. "Thermal Decomposition of CF3and the Reaction of CF2+ OH → CF2O + H." Journal of Physical Chemistry A 112, no. 1 (January 2008): 31–37. http://dx.doi.org/10.1021/jp076344u.

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47

Čermák, Jan, Kateřina Auerová, Huong Thi Thu Nguyen, Vratislav Blechta, Pavel Vojtíšek, and Jaroslav Kvíčala. "Synthesis of Rhodium Complexes with Novel Perfluoroalkyl Substituted Cyclopentadienyl Ligands." Collection of Czechoslovak Chemical Communications 66, no. 2 (2001): 382–96. http://dx.doi.org/10.1135/cccc20010382.

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Mixtures of isomers of (perfluoroalkyl)tetramethylcyclopenta-1,3-dienes (CH3)4C5H(CF2)nCF3 (n = 3, 5, 7, 9) were synthesized as precursors of new cyclopentadienyl ligands for organotransition metal catalysis in fluorous biphase media and characterized by combination of GC-MS and 13C NMR spectroscopy. Rhodium(III) chloro complexes [Rh{(CH3)4C5(CF2)nCF3}Cl2]2 and rhodium(I) carbonyl complexes [Rh{(CH3)4C5(CF2)nCF3}(CO)2] were prepared from the cyclopentadienes and molecular structure of [Rh{(CH3)4C5(CF2)5CF3}Cl2]2 was determined by X-ray diffraction. The ligands are electronically close to the unsubstituted cyclopentadienyl as shown by values of carbonyl stretching frequencies in the carbonyl complexes. Neither carbonyl frequencies nor NMR chemical shifts of the complexes are substantially affected by the length of the perfluoroalkyl chain.

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48

Binnewies, M., J. Grobe, and D. Le Van. "REAKTIVE E[dbnd]C (p-p) π-SYSTEME II: MASSENSPEKTROMETRISCHE UNTERSUCHUNG VON F3CP[dbnd]CF2, F3CAs[dbnd]CF2, S[dbnd]CF2UND Se[dbnd]CF2." Phosphorus and Sulfur and the Related Elements 21, no. 3 (January 1985): 349–55. http://dx.doi.org/10.1080/03086648508077678.

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49

Sun, Xiaoyan, Lei Ding, Qingzhu Zhang, and Wenxing Wang. "Atmospheric oxidation mechanism of polyfluorinated sulfonamides — A quantum chemical and kinetic study." Canadian Journal of Chemistry 91, no. 6 (June 2013): 472–78. http://dx.doi.org/10.1139/cjc-2012-0486.

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Polyfluorinated sulfonamides (FSAs, F(CF2)nSO2NR1R2) are present in the atmosphere and may serve as the source of perfluorocarboxylates (PFCAs, CF3(CF2)nCOO–) in remote locations through long-range atmospheric transport and oxidation. Density functional theory (DFT) molecular orbital theory calculations were carried out to investigate OH radical-initiated atmospheric oxidation of a series of sulfonamides, F(CF2)nSO2NR1R2 (n = 4, 6, 8). Geometry optimizations of the reactants as well as the intermediates, transition states, and products were performed at the MPWB1K level with the 6-31G+(d,p) basis set. Single-point energy calculations were carried out at the MPWB1K/6-311+G(3df,2p) level of theory. The OH radical-initiated reaction mechanism is given and confirms that the OH addition to the sulfone double bond producing perfluoroalkanesulfonic acid directly cannot occur in the general atmosphere. Canonical variational transition-state (CVT) theory with small curvature tunneling (SCT) contribution was used to predict the rate constants. The overall rate constants were determined, k(T) (N-EtFBSA + OH) = (3.21 × 10−12) exp(–584.19/T), k(T) (N-EtFHxSA + OH) = (3.21 × 10−12) exp(–543.24/T), and k(T) (N-EtFOSA + OH) = (2.17 × 10−12) exp(–504.96/T) cm3 molecule−1 s−1, over the possible atmospheric temperature range of 180–370 K, indicating that the length of the F(CF2)n group has no large effect on the reactivity of FSAs. Results show that the atmospheric lifetime of FSAs determined by OH radicals will be 20–40 days, which agrees well with the experimental values (20–50 days), 20 thus they may contribute to the burden of perfluorinated pollution in remote regions.

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50

Suga, N., H. Niwa, I. Taniguchi, and D. Margoliash. "The personalized auditory cortex of the mustached bat: adaptation for echolocation." Journal of Neurophysiology 58, no. 4 (October 1, 1987): 643–54. http://dx.doi.org/10.1152/jn.1987.58.4.643.

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1. In the mustached bat, Pteronotus parnellii, the "resting" frequency of the constant-frequency component of the second harmonic (CF2) of the orientation sound (biosonar signal) is different among individuals within a range from 59.69 to 63.33 kHz. The standard deviation of CF2 resting frequency is 0.091 kHz on the average for individual bats. The male's CF2 resting frequency (61.250 +/- 0.534 kHz, n = 58) is 1.040 kHz lower than the female's (62.290 +/- 0.539 kHz, n = 58) on the average. Females' resting frequencies measured in December are not different from those measured in April when almost all of them are pregnant. Therefore, the orientation sound is sexually dimorphic. 2. In the DSCF (Doppler-shifted CF processing) area of the auditory cortex, tonotopic representation differs among individual bats. The higher the CF2 resting frequency of the bat's own sound, the higher the frequencies represented in the DSCF area of that bat. There is a unique match between the tonotopic representation and the CF2 resting frequency. This match indicates that the auditory cortex is "personalized" for echolocation and that the CF2 resting frequency is like a signature of the orientation sound. 3. If a bat's resting frequency is normalized to 61.00 kHz, the DSCF area overrepresents 60.6-62.3 kHz. The central region of this overrepresented band is 61.1-61.2 kHz. This focal band matches the "reference" frequency to which the CF2 frequency of a Doppler-shifted echo is stabilized by Doppler-shift compensation. 4. Since DSCF neurons are extraordinarily sharply tuned in frequency, the personalization of the auditory cortex or system is not only suited for the detection of wing beats of insects, but also for the reduction of the masking effect on echolocation of consepecific's biosonar signals. 5. Because the orientation sound is sexually dimorphic and the auditory cortex is personalized, the tonotopic representation of the auditory cortex is also sexually dimorphic.

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