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91.
Acylsulfonamides can be rapidly and conveniently synthesized from a variety of carboxylic acids and sulfonamides utilizing the commercially available reagents, PS-DCC and DMAP under mild reaction conditions. DMAP can be efficiently scavenged by utilization of a silica-supported tosic acid cartridge (Si-SCX). In most of the cases studied, products with high purities and yields were obtained without the need for further purification. 相似文献
92.
Wafaa N. Aldhafiri Yashpal S. Chhonker Yuning Zhang Don W. Coutler Timothy R. McGuire Rongshi Li Daryl J. Murry 《Molecules (Basel, Switzerland)》2020,25(24)
MP1 is a novel marinopyrrole analogue with activity in MYCN amplified neuroblastoma cell lines. A rapid, selective, and sensitive liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method was developed and validated for quantitation of MP1 in mouse plasma. Analyte separation was achieved using a Waters Acquity UPLC®BEH C18 column (1.7 µm, 100 × 2.1 mm). Mobile phase consisted of 0.1% acetic acid in water (10%) and methanol (90%) at a total flow rate of 0.25 mL/min. The mass spectrometer was operated at unit resolution in the multiple reaction monitoring (MRM) mode, using precursor ion > product ion transitions of 324.10 > 168.30 m/z for MP1 and 411.95 > 224.15 m/z for PL-3. The MS/MS response was linear over the concentration range from 0.2–500 ng/mL for MP1, correlation coefficient (r2) of 0.988. Precision (% RSD) and accuracy (% bias) were within the acceptable limits as per FDA guidelines. MP1 was stable under storage and laboratory handling conditions. The validated method was successfully applied to assess the solubility, in-vitro metabolism, plasma protein binding, and bio-distribution studies of MP1. 相似文献
93.
Formulas for the doubly stochastic square roots of the idempotents are presented. Such square roots must necessarily satisfy per A2≤perA. 相似文献
94.
Simon Trudel E. Daryl Crozier Peter S. Budnik 《Journal of solid state chemistry》2011,184(5):1025-19128
The oxidation state and local geometry of the metal centers in amorphous thin films of Fe2O3 (Fe3+ oxidation state), CoFe2O4 (Co2+/Fe3+ oxidation states), and Cr2O3 (Cr3+ oxidation state) are determined using K edge X-ray absorption near-edge structure (XANES) spectroscopy and extended X-ray absorption fine structure (EXAFS) spectroscopy. The metal oxide thin films were prepared by the solid-state photochemical decomposition of the relevant metal 2-ethylhexanoates, spin cast as thin films. No peaks are observed in the X-ray diffraction patterns, indicating the metal oxides are X-ray amorphous. The oxidation state of the metals is determined from the edge position of the K absorption edges, and in the case of iron-containing samples, an analysis of the pre-edge peaks. In all cases, the EXAFS analysis indicates the first coordination shell consists of oxygen atoms in an octahedral geometry, with a second shell consisting of metals. No higher shells are observed beyond 3.5 Å for all samples, indicating the metal oxides are truly amorphous, consistent with X-ray diffraction results. 相似文献
95.
Stathis Filippas Luisa Moschini Achilles Tertikas 《Archive for Rational Mechanics and Analysis》2013,208(1):109-161
In this work we establish trace Hardy and trace Hardy–Sobolev–Maz’ya inequalities with best Hardy constants for domains satisfying suitable geometric assumptions such as mean convexity or convexity. We then use them to produce fractional Hardy–Sobolev–Maz’ya inequalities with best Hardy constants for various fractional Laplacians. In the case where the domain is the half space, our results cover the full range of the exponent ${s \in}$ (0, 1) of the fractional Laplacians. In particular, we give a complete answer in the L 2 setting to an open problem raised by Frank and Seiringer (“Sharp fractional Hardy inequalities in half-spaces,” in Around the research of Vladimir Maz’ya. International Mathematical Series, 2010). 相似文献
96.
97.
Philip C.W. Cheung Daryl R. Williams Jack Barrett James Barker Donald W. Kirk 《Molecules (Basel, Switzerland)》2021,26(17)
In this work, the authors attempt to interpret the visible, infrared and Raman spectra of ferrate(VI) by means of theoretical physical-inorganic chemistry and historical highlights in this field of interest. In addition, the sacrificial decomposition of ferrate(VI) during water treatment will also be discussed together with a brief mention of how Rayleigh scattering caused by the decomposition of FeVIO42− may render absorbance readings erroneous. This work is not a compendium of all the instrumental methods of analysis which have been deployed to identify ferrate(VI) or to study its plethora of reactions, but mention will be made of the relevant techniques (e.g., Mössbauer Spectroscopy amongst others) which support and advance this overall discourse at appropriate junctures, without undue elaboration on the foundational physics of these techniques. 相似文献
98.
We experimentally investigate a method of directly characterizing the photon-number distribution of nonclassical light beams that is tolerant to losses and makes use of only standard binary detectors. This is achieved in a single measurement by calibrating the detector using some small amount of prior information about the source. We demonstrate the technique on a freely propagating heralded two-photon-number state created by conditional detection of a two-mode squeezed state generated by parametric down-conversion. 相似文献
99.
We introduce an application of thermionic emission in a PMT photocathode. Because of the nonlinear dependence of thermionic emission on absorbed laser power, a conventional PMT is found to produce a virtual pinhole effect that rejects unfocused light at least as strongly as a physical pinhole. This virtual pinhole effect is exploited in a scanning transmission confocal microscope equipped with a cw laser source. Because the area of the PMT photocathode is large, signal descanning is not required and thermionic detection acts as a self-aligned pinhole. Our technique of thermionic-detection autoconfocal microscopy is further implemented with graded-field contrast to obtain enhanced phase-gradient sensitivity in unlabeled samples, such as rat hippocampal brain slices. 相似文献
100.
Daryl E. Freeman 《Chemical physics letters》1973,18(3):345-346
Counter examples are presented that negate the generality of Gans' claim that a singular jacobian demands the existence of one off-diagonal force constant Fst possessing the extremal property ?Frr/?Fst = ∞ for all of the n diagonal force constants Frr (r = 1, > 62; n) in a symmetry species containing n vibrations. 相似文献