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101.
Polarized Raman microspectroscopy and atomic force microscopy were used to measure molecular orientation in individual diphenylalanine nanotubes (diameters ranging from 100 nm to 1000 nm). Analysis of the amide I Raman bands (1686 cm(-1)) indicated that the C=O side chains have a parallel alignment with the nanotube axis. The amide III Raman band (1249 cm(-1)) associated with the peptide backbone C-N vibrations showed that these bonds are preferentially aligned perpendicular to the nanotube axis. However, the Raman band corresponding to the symmetric breathing mode of the aromatic rings (1002 cm(-1)) indicated a rather random orientation. These results support the theoretical molecular structure models proposed recently. 相似文献
102.
Free choice sequences: A temporal interpretation compatible with acceptance of classical mathematics
Saul A. Kripke 《Indagationes Mathematicae》2019,30(3):492-499
This paper sketches a way of supplementing classical mathematics with a motivation for a Brouwerian theory of free choice sequences. The idea is that time is unending, i.e. that one can never come to an end of it, but also indeterminate, so that in a branching time model only one branch represents the ‘actual’ one. The branching can be random or subject to various restrictions imposed by the creating subject. The fact that the underlying mathematics is classical makes such perhaps delicate issues as the fan theorem no longer problematic. On this model, only intuitionistic logic applies to the Brouwerian free choice sequences, and there it applies not because of any skepticism about classical mathematics, but because there is no ‘end of time’ from the standpoint of which everything about the sequences can be decided. 相似文献
103.
Salter RS Douglas D McRobbie L Quintana J Legg D Schwartz J Conaway D McPhee C Saul S Markovsky R 《Journal of AOAC International》2011,94(1):348-357
The Charm 3 SL3 beta-Lactam Test is a 3 min receptor-based lateral-flow Rapid One-Step Assay (ROSA) that detects the six beta-lactam drugs of concern approved for dairy cattle in the United States. The method is a biochemical formulation change of the SL3 beta-Lactam Test evaluated and approved in 2007. The Charm 3 SL3 was evaluated under the AOAC Research Institute Performance Tested Method (PTM) program following the protocol of the U.S. Food and Drug Administration, Center for Veterinary Medicine. The method was approved as PTM 071002 on May 8, 2009. The following drugs were detected in three combined lots: penicillin G at 3.8 ppb, ampicillin at 8.0 ppb, amoxicillin at 8.4 ppb, cephapirin at 20.0 ppb, ceftiofur (total metabolites) at 79 ppb, and cloxacillin at 8.6 ppb > or = 90% of the time with 95% confidence. These detection levels are lower than, but within 75% of, the U.S. Safe Level/Tolerances. Lot-to-lot repeatability was typically within 20% of these determined levels. The test kit was found to be suitable for testing thawed frozen samples. It was also found to respond with equal or better sensitivity to samples that contained incurred analytes, i.e., both the microbiologically active parent drug and its active metabolites. There were no interferences from somatic cells at 1.1 million/mL, bacterial cells at 300 000 CFU/mL, or 32 other non-beta-lactam drugs at 100 ppb. Ruggedness experiments indicated that the test procedure is robust. These results meet the fit-for-purpose approval criteria for inclusion in the National Conference for Interstate Milk Shipments milk testing program. 相似文献
104.
Lapidus SH McConnell AC Stephens PW Miller JS 《Chemical communications (Cambridge, England)》2011,47(27):7602-7604
Mn(II)(TCNE)I(OH(2)) was isolated from the reaction of tetracyanoethylene (TCNE) and MnI(2)(THF)(3), and has a 2-D structure possessing an unusual, asymmetric bonded μ(4)-[TCNE]˙(-). Direct antiferromagnetic coupling between the S = 5/2 Mn(II) and S = 1/2 [TCNE]˙(-) leads to magnetic ordering as a canted antiferrimagnet at a T(c) of 171 K. 相似文献
105.
106.
Dr. Saul H. Lapidus Prof. Peter W. Stephens Dr. Christopher M. Kareis Peter E. VanNatta Prof. Joel S. Miller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1752-1757
The reaction of MnII(O2CMe)2 and NaCN or LiCN in water forms a light green insoluble material. Structural solution and Rietveld refinement of high-resolution synchrotron powder diffraction data for this unprecedented, complicated compound of previously unknown composition revealed a new alkali-free ordered structural motif with [MnII4(μ3-OH)4]4+ cubes and octahedral [MnII(CN)6]4− ions interconnected in 3D by MnII-N≡C-MnII linkages. The composition is {[MnII(OH2)3][MnII(OH2)]3}(μ3-OH)4][MnII(μ-CN)2(CN)4] ⋅ H2O=[MnII4(μ3-OH)4(OH2)6][MnII(μ-CN)2(CN)4] ⋅ H2O, which is further simplified to [Mn4(OH)4][Mn(CN)6](OH2)7 ( 1 ). 1 has four high-spin (S=5/2) MnII sites that are antiferromagnetically coupled within the cube and are antiferromagnetically coupled to six low-spin (S=1/2) octahedral [MnII(CN)6]4− ions. Above 40 K the magnetic susceptibility, χ(T), can be fitted to the Curie–Weiss expression, χ ∝(T−θ)−1, with θ=−13.4 K, indicative of significant antiferromagnetic coupling and 1 orders as an antiferromagnet at Tc=7.8 K. 相似文献
107.
Mahyar Ali Miessner Hans Mueller Siegfried Hama Aziz Kosar Hikmat Kalass Dieter Moeller Detlev Kretschmer Klaus Robles Manuel Saul Noack Johannes 《Plasma Chemistry and Plasma Processing》2019,39(3):531-544
Plasma Chemistry and Plasma Processing - The degradation of perfluorosurfactants (PFS), particularly of PFOS, has been studied in dielectric barrier discharge (DBD) and nano-pulse corona discharge... 相似文献
108.
We present an analytic prediction for the full hadronic multiplicity distribution in deep-inelastic lepton-nucleon scattering. We obtain a distinctive relationship between the average multiplicity at any W and that in e+e? annihilation. 相似文献
109.
110.
Saul Barshay 《Zeitschrift fur Physik C Particles and Fields》1990,47(2):199-203
We exhibit intermittent behavior in multiparticle production from explicit calculations within an idealized model in configuration space. The origin of intermittency with dependence uponn lies in the existence of a multitude of independent multiplicity distributions, of different form, over the impact-parameter plane. We also generalize these considerations to the longitudinal direction, along the collision line. 相似文献