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We evaluated a method that determines the optimal grid parameters of potential-field data such as the intervals of grid nodes and the grid azimuth. Optimal grid parameters produced the best gridding results with the least amount o...
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We evaluated a method that determines the optimal grid parameters of potential-field data such as the intervals of grid nodes and the grid azimuth. Optimal grid parameters produced the best gridding results with the least amount of data distortions. We used spectral analysis of the data statistics on azimuth projections. The direction with the largest degree of periodicity was defined as the optimal azimuth of the grid. The grid line interval was determined according to the frequency point with the largest amplitude value. By spectral analysis of the data sequence projected in the direction normal to the survey lines, grid point spacing was also determined. Correlative analysis of the template matching method was used to determine the optimal grid range. Tests on simulated and field data proved that this method is rather robust and can be incorporated into gridding software packages.
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A new precise determination of the η meson mass is presented. It is based on a measurement of the threshold for the γp → pη reaction using the tagger focal-plane microscope detector at the MAMI-B facility in Mainz. The tagger ...
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A new precise determination of the η meson mass is presented. It is based on a measurement of the threshold for the γp → pη reaction using the tagger focal-plane microscope detector at the MAMI-B facility in Mainz. The tagger microscope has a higher energy resolution than the standard tagging spectrometer and, hence, allowed an improvement in the accuracy compared to the previous η mass measurement at MAMI-B. Special emphasis was put on a very careful energy calibration of the electron beam and the tagging device, which reduced considerably the systematic uncertainty compared to the previous MAMI experiment. The result m_η = (547.865±0.031_(stat)±0.062_(syst))MeV agrees very well with the precise values of the NA48, KLOE, CLEO and COSY-ANKE Collaborations and deviates by 6σ from the smaller value obtained by the GEM Collaboration at COSY.
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An LC-DAD method was developed for determination of lobeline from in vitro and in vivo cultures of Lobelia inflata. Samples were extracted with 0.1 N HCl-acetonitrile (1: 1, v/v), and purified by solid-phase extraction. Optimized ...
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An LC-DAD method was developed for determination of lobeline from in vitro and in vivo cultures of Lobelia inflata. Samples were extracted with 0.1 N HCl-acetonitrile (1: 1, v/v), and purified by solid-phase extraction. Optimized conditions resulted in high recovery. LC separations were performed on an Eurosphere C8 reversed-phase column using 30:70 (v/v) acetonitrile-0.1 % trifluoroacetic acid as a mobile phase. Quantitative determination of lobeline was performed by external standard method at 250 nm, in the range of 2.4-80 mu g mL(-1). Validation studies proved that the repeatability of the method was good and the recovery was satisfactory. In vitro organized cultures contained considerable amount of lobeline (herb: 175 mu g g(-1), root: 100 mu g g(-1)). When these cultures were transplanted into the open field, the lobeline content increased significantly (herb: 323 mu g g(-1), root: 833 mu g g(-1)). Plants obtained from seed propagation contained 382 mu g g(-1) lobeline gin the herb. For direct characterization of di-substituted piperidine alkaloids in extracts of L. inflata, tandem mass spectrometric method was developed using electrospray ionization. Analysis was performed in the positive ion mode on a triple quadropole LC-MS system. LC separations were achieved on Eurosphere C8 column with a modified mobile phase (acetonitrile-30 mM ammonium Formate, pH 2.80) to ensure proper molecular ionization. The identification and structural elucidation of the alkaloids were performed by comparing their changes in molecular mass (AM), full-scan MS-MS spectra with those of lobeline, norlobelanine and lobelanidine. These alkaloids and ten other derivatives were identified in the plant extracts. Three piperidine alkaloids were reported in L. inflata for the first time.
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In 1849, Hippolyte Fizeau determined the speed of light in a famous experiment. The idea was to measure the time taken for a pulse of light to travel between an intense light source and a mirror about 8 km away. A rotating cogwhee...
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In 1849, Hippolyte Fizeau determined the speed of light in a famous experiment. The idea was to measure the time taken for a pulse of light to travel between an intense light source and a mirror about 8 km away. A rotating cogwheel with 720 notches, that could be rotated at a variable speed, was used to chop the light beam and determine the flight time. In 2017, physicists and technicians of the University of Mons in Belgium reproduced the experiment with modern devices to allow members of the public to measure the speed of light themselves. The light source used was a low power laser, and the cogwheel was replaced by an electrically driven chopper, but the general spirit of Fizeau's experiment was preserved. The exhibition was organised in the belfry of Mons, a baroque-style building classified as a UNESCO World Heritage site. The solutions found for the main problems encountered are presented here to help colleagues intending to reproduce the experiment.
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A gas chromatographic method is described for the determination of residual 2-(acryloyloxy)ethyl isocyanate (AOI) and 2-(methacryloyloxy)ethyl isocyanate (MOI) as curing agents in an ultraviolet curable adhesive. Pre-column deriva...
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A gas chromatographic method is described for the determination of residual 2-(acryloyloxy)ethyl isocyanate (AOI) and 2-(methacryloyloxy)ethyl isocyanate (MOI) as curing agents in an ultraviolet curable adhesive. Pre-column derivatization was employed in the determination of AOI and MOI as a means of enhancing the response of the flame ionization detector. Urethane derivatives of AOI and MOI were derived using methanol for 30 min at room temperature. The accuracies (n = 5, three concentration levels) were in the range of 113.4 to 126.7%, and precisions (n = 5, three concentration levels) were in the range of 0.8 to 4.3% for AOI-OMe. Furthermore, the accuracies were in the range of 79.5 to 108.6% and the precisions were in the range of 1.0 to 2.4% for MOI-OMe. The correlation coefficients of six calibration standards were all greater than 0.9999 for AOI-OMe and greater than 0.9998 for MOI-OMe over the range from 10 to 100 μg/mL.
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The determination of vanadium(V) and chromium(VI) in a single sample on a support disk was studied. Polyacrylonitrile fiber filled with an AV-17 anion exchanger was used as a solid phase. After adsorption, the elements were succes...
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The determination of vanadium(V) and chromium(VI) in a single sample on a support disk was studied. Polyacrylonitrile fiber filled with an AV-17 anion exchanger was used as a solid phase. After adsorption, the elements were successively detected in the solid phase by color complexation reactions of vanadium with 8-hydroxyquinoline-5-sulfonic acid and chromium with 1.5-diphenylcarbazide. A procedure was developed for the adsorption-spectroscopic determination of 0.04-0.4 mu g/mL vanadium(V) and 0.01-0.05 mu m/mL chromium(VI) at V: Cr ratios of 1: 1 to 10: 1 in the dynamic mode. The limits of detections for vanadium and chromium were 0.04 and 0.005 mu g/mL, respectively. It was shown that the background salt content of potable water had no appreciable effect; no preliminary sample preparation was required.
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In our article, we argued that philosophical and practical challenges regarding "belief" and "accuracy of belief" make it difficult to determine when a patient is in denial, unrealistically optimistic, or self-deceived, as opposed...
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In our article, we argued that philosophical and practical challenges regarding "belief" and "accuracy of belief" make it difficult to determine when a patient is in denial, unrealistically optimistic, or self-deceived, as opposed to merely hopeful. Furthermore, we argued that even if we could make these determinations, doing so does not provide an answer about the normative status of denial, because beliefs that are unrealistic are not always as harmful as critics contend. We concluded with a recommendation for a more permissive approach to patients who are perceived to be unrealistically optimistic, in denial, or self-deceived. Unless they significantly misunderstand their situation and thus make decisions that are clearly bad for them, we should not intervene by trying to change their mental states, persuade them to behave differently, or by paternalistically denying them certain options. We received many thoughtful commentaries in response. Here, we respond to key points.
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U.S. EPA Method 531.2 describes the determination of widely used carbamate pesticides in raw surface water using HPLC with fluorescence detection following postcolumn derivatization, which enhances method sensitivity and selectivi...
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U.S. EPA Method 531.2 describes the determination of widely used carbamate pesticides in raw surface water using HPLC with fluorescence detection following postcolumn derivatization, which enhances method sensitivity and selectivity as compared to UV absorbance detection. Per European Union (EU) regulation 98/83/EC for pesticides in drinking water, the maximum admissible concentration of each individual pesticide component is 0.1 μg/L, and the total concentration is not to exceed 0.5 μg/L. Detection of these regulated compounds at such low concentrations poses a challenge for many water testing laboratories using EPA Method 531.2.
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This paper considers the empirical evidence that we currently have for various kinds of determinism that might be relevant to the thesis that human beings possess libertarian free will. Libertarianism requires a very strong versio...
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This paper considers the empirical evidence that we currently have for various kinds of determinism that might be relevant to the thesis that human beings possess libertarian free will. Libertarianism requires a very strong version of indeterminism, so it can be refuted not just by universal determinism, but by some much weaker theses as well. However, it is argued that at present, we have no good reason to believe even these weak deterministic views and, hence, no good reason—at least from this quarter—to doubt that we are libertarian free. In particular, the paper responds to various arguments for neural and psychological determinism, arguments based on the work of people like Honderich, Tegmark, Libet, Velmans, Wegner, and Festinger. Keywords Determinism - Libertarianism - Free will - Neural determinism - Psychological determinism
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