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Misha Chertkov Bob Ecke Gregory Eyink Darryl Holm 《Journal of statistical physics》2003,113(5-6):637-642
115.
Bob Coecke 《Foundations of Physics Letters》1995,8(5):437-447
We generalize Aerts' proof concerning the existence of hidden measurements for experiments withn outcomes to general experiments with an infinite set of outcomes. More specific we prove that, if is a set of experiments on an entityS with a set of pure states , and alle are such that the outcomes can be represented as a measurable subset of a finite dimensional real space, on which for every initial state of the entity there exists a probability measure, then there exists a hidden measurement representation for this set of experiments.Research Assistant of the National Fund for Scientific Research.Supported by Flanders' Federale Diensten voor Wetenschappelijke, Technische en Culturele Aangelegenheden in the framework of IUAP-III No 9. 相似文献
116.
Chieh‐Ting Lin Jinho Lee Jinhyun Kim Thomas J. Macdonald Jonathan Ngiam Bob Xu Matyas Daboczi Weidong Xu Sebastian Pont Byoungwook Park Hongkyu Kang Ji‐Seon Kim David J. Payne Kwanghee Lee James R. Durrant Martyn A. McLachlan 《Advanced functional materials》2020,30(7)
The origin of performance enhancements in p‐i‐n perovskite solar cells (PSCs) when incorporating low concentrations of the bulky cation 1‐naphthylmethylamine (NMA) are discussed. A 0.25 vol % addition of NMA increases the open circuit voltage (Voc) of methylammonium lead iodide (MAPbI3) PSCs from 1.06 to 1.16 V and their power conversion efficiency (PCE) from 18.7% to 20.1%. X‐ray photoelectron spectroscopy and low energy ion scattering data show NMA is located at grain surfaces, not the bulk. Scanning electron microscopy shows combining NMA addition with solvent assisted annealing creates large grains that span the active layer. Steady state and transient photoluminescence data show NMA suppresses non‐radiative recombination resulting from charge trapping, consistent with passivation of grain surfaces. Increasing the NMA concentration reduces device short‐circuit current density and PCE, also suppressing photoluminescence quenching at charge transport layers. Both Voc and PCE enhancements are observed when bulky cations (phenyl(ethyl/methyl)ammonium) are incorporated, but not smaller cations (Cs/MA)—indicating size is a key parameter. Finally, it demonstrates that NMA also enhances mixed iodide/bromide wide bandgap PSCs (Voc of 1.22 V with a 1.68 eV bandgap). The results demonstrate a facile approach to maximizing Voc and provide insights into morphological control and charge carrier dynamics induced by bulky cations in PSCs. 相似文献
117.
Factorial design (FD) was applied in order to develop an optimised method for the detection of chemical warfare (CW) agent simulant compounds on Porapak Q. Application of FD allowed study of the adsorption/desorption mechanism of analytes. Di(propylene glycol) monomethyl ether (DPM) and methyl salicylate (MS) were selected for study as both compounds are employed in agent simulation trials but are currently analysed by different methods. An analytical method for simultaneous determination of both compounds was developed using solvent desorption. The optimised method identified non-polar interactions as the primary adsorption/desorption mechanism. Steel tubes were shown to be more suited for sampling of simulants, due to lower variability in recovery compared to glass tubes. Atmospheric detection limits for both simulants were estimated to be 0.2 mg m(-3) allowing the trace analysis of these compounds by gas chromatography with flame ionisation detection (GC-FID). 相似文献
118.
Jennifer A. Saltmarsh Bob A. Howell Philip J. Squattrito 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e335-e337
The title complexes, [Pt(C4H7NO)2I2], (I), and [Pt(C4H9NO)2I2], (II), possess similar square‐planar coordination geometries with modest distortions from ideality. For (I), the cis‐L—Pt—L angles are in the range 87.0 (4)–94.2 (3)°, while the trans angles are 174.4 (3) and 176.4 (3)°. For (II), cis‐L—Pt—L are 86.1 (8)–94.2 (6)° and trans‐L—Pt—L are 174.4 (6) and 177.4 (5)°. One 3,6‐dihydro‐2H‐1,2‐oxazine ligand in (I) is rotated so that the N—O bond is out of the square plane by approximately 70°, while the N—C bond is only ca 20° out of the plane. The other oxazine ligand is rotated so that the N—C bond is about 80° out of the plane, while the N—O bond is out of the plane by approximately 24°. In (II), the 3,4,5,6‐tetrahydro‐2H‐1,2‐oxazine ligands are also positioned with one having the N—O bond further out of the plane and the other having the N—C bond positioned in that fashion. Both ligands, however, are rotated approximately 90° compared with their positions in (I). In both complexes, this results in an unsymmetrical distortion of the I—Pt—N bond angles in which one is expanded and the other contracted. These features are compared to those of reported cis‐diaminediiodoplatinum(II) complexes. 相似文献
119.
Bob Stanley Kevin A. Mehr Trent Kellock Jonathan D. Van Hamme Kingsley K. Donkor 《Journal of separation science》2009,32(17):2993-3000
A sensitive micellar electrokinetic chromatography (MEKC) method was developed for the separation and determination of four closely related lantibiotics: gallidermin, cinnamycin, duramycin and nisin. Factors affecting the separation of the lantibiotics such as pH, phosphate buffer concentration, SDS concentration and wavelength for UV detection were investigated. By optimizing these experimental conditions, successful separation was achieved between class 1A lantibiotics (nisin and gallidermin) and class 1B lantibiotics (duramycin and cinnamycin). The four lantibiotics were separated within 12 min in 50 mM phosphate buffer at pH 3.95 ± 0.1 containing 80 mM SDS with UV detection of 214 nm. The LOD (S/N = 3) were 61 ng/mL for gallidermin, 57 ng/mL for cinnamycin, 55 ng/mL for duramycin and 58 ng/mL for nisin. The method was successfully applied to real samples such as fermentation broth, bovine colostrum and predrop beer. This method yielded satisfactory results, with quantitative recoveries of spiked lantibiotics in the three samples ranging from 86.1 to 99.6%. 相似文献
120.
Nadeau JS Wilson RB Hoggard JC Wright BW Synovec RE 《Journal of chromatography. A》2011,1218(50):9091-9101
An in-depth study is presented to better understand how data reduction via averaging impacts retention alignment and the subsequent chemometric analysis of data obtained using gas chromatography (GC). We specifically study the use of signal averaging to reduce GC data, retention time alignment to correct run-to-run retention shifting, and principal component analysis (PCA) to classify chromatographic separations of diesel samples by sample class. Diesel samples were selected because they provide sufficient complexity to study the impact of data reduction on the data analysis strategies. The data reduction process reduces the data sampling ratio, S(R), which is defined as the number of data points across a given chromatographic peak width (i.e., the four standard deviation peak width). Ultimately, sufficient data reduction causes the chromatographic resolution to decrease, however with minimal loss of chemical information via the PCA. Using PCA, the degree of class separation (DCS) is used as a quantitative metric. Three "Paths" of analysis (denoted A-C) are compared to each other in the context of a "benchmark" method to study the impact of the data sampling ratio on preserving chemical information, which is defined by the DCS quantitative metric. The benchmark method is simply aligning data and applying PCA, without data reduction. Path A applies data alignment to collected data, then data reduction, and finally PCA. Path B applies data reduction to collected data, and then data alignment, and finally PCA. The optimized path, namely Path C, is created from Paths A and B, whereby collected data are initially reduced to fewer data points (smaller S(R)), then aligned, and then further reduced to even fewer points and finally analyzed with PCA to provide the DCS metric. Overall, following Path C, one can successfully and efficiently classify chromatographic data by reducing to a S(R) of ~15 before alignment, and then reducing down to S(R) of ~2 before performing PCA. Indeed, following Path C, results from an average of 15 different column length-with-temperature ramp rate combinations spanning a broad range of separation conditions resulted in only a ~15% loss in classification capability (via PCA) when the loss in chromatographic resolution was ~36%. 相似文献