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101.
102.
We put forward a method that allows the experimental determination of the entire spatial mode spectrum of any arbitrary monochromatic wave field in a plane normal to its propagation direction. For coherent optical fields, our spatial spectrum analyzer can be implemented with a small number of benchmark refractive elements embedded in a single Mach-Zehnder interferometer. We detail an efficient setup for measuring in the Hermite-Gaussian mode basis. Our scheme should also be feasible in the context of atom optics for analyzing the spatial profiles of macroscopic matter waves. 相似文献
103.
Sansoni L Sciarrino F Vallone G Mataloni P Crespi A Ramponi R Osellame R 《Physical review letters》2012,108(1):010502
Quantum walk represents one of the most promising resources for the simulation of physical quantum systems, and has also emerged as an alternative to the standard circuit model for quantum computing. Here we investigate how the particle statistics, either bosonic or fermionic, influences a two-particle discrete quantum walk. Such an experiment has been realized by exploiting polarization entanglement to simulate the bunching-antibunching feature of noninteracting bosons and fermions. To this scope a novel three-dimensional geometry for the waveguide circuit is introduced, which allows accurate polarization independent behavior, maintaining remarkable control on both phase and balancement. 相似文献
104.
Roberta Sburlati 《Journal of Elasticity》2009,95(1-2):79-97
In this paper, we propose a method for the solution of the axisymmetric boundary value problem for a finite elastic cylinder with assigned stress and/or displacements acting on the ends and side. The technique utilizes the Love representation, which allows for reduction of the solution of the elastic problem to the search for a biharmonic function on a cylindrical domain. In the solution method suggested here, we write the Love function with a Bessel expansion and analyze in detail the conditions under which it is possible to differentiate the expansion term by term. We show that this is possible only for a restricted class of elastic solutions. In the general case, we introduce two new auxiliary functions of the z-coordinate. In this way, we obtain the general form of the axisymmetric biharmonic function, which is discussed in relation to certain specific boundary conditions applied on the side and ends of the cylinder. We obtain an exact explicit solution of practical interest for a cylinder with free ends and assigned displacements applied to the side. 相似文献
105.
Sala F Bagnati R Livi V Cereda R D'Incalci M Zucchetti M 《Journal of mass spectrometry : JMS》2011,46(10):1039-1045
E-3810, 6-[[7-[(1-aminocyclopropyl)methoxy]-6-methoxy-4-quinolyl]oxy]-N-methyl-naphthalene-1-carboxamide, is a novel, potent, dual inhibitor of vascular endothelial growth factor and fibroblast growth factor receptors with antiangiogenic properties, now under early clinical evaluation as an anticancer agent. To investigate its clinical pharmacokinetics, a high-performance liquid chromatography-tandem mass spectrometry method was developed and validated to measure the drug in human plasma on the basis of simple protein precipitation with methanol after addition of deuterated E-3810 as internal standard. The method requires a small volume of sample (100 μl) and is rapid and selective, allowing good resolution of peaks in 5 min. It is sensitive, precise, and accurate, with overall precision, expressed as CV%, always ≤7.1%, accuracy in the range 92.7%-104.4%, and high recovery, close to 100%. The limit of detection is 0.01 ng/ml, and the lower limit of quantitation is 2.0 ng/ml. The assay was validated in the range from the lower limit of quantitation up to 500.0 ng/ml. This is the first method developed and validated for analyzing E-3810 in human plasma. The method has been successfully applied to study E-3810 pharmacokinetics in cancer patients with solid tumors who are receiving daily oral doses of the drug during the phase I trial. 相似文献
106.
Tamara Mengoni Dolores Vargas Peregrina Roberta Censi Manuela Cortese Massimo Ricciutelli 《Natural product research》2016,30(3):268-275
The aim of this work was to provide a characterisation of volatile constituents from different commercial batches of henna (Lawsonia inermis) leaves of different geographic origin. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) was used for the purpose. A total of 72 components were identified by GC–MS in the headspace of different henna samples which proved to differ considerably from each other, because they were characterised by different classes of components, mainly aliphatic compounds (9.0–64.7%), terpenoids (5.8–45.5%) and aromatics (7.9–45.2%), with alkanes (0.9–18.5%), aldehydes (2.1–18.8%) and carboxylic acids (3.1–29.3%), monoterpenes (3.4–30.0%) and sesquiterpenes (0.8–23.7%) and phenyl propanoids (0.6–43.1%), being the most abundant, respectively. Major representatives of these groups were n-hexadecane (0.5–4.7%), (2E)-hexenal (0.5–11.7%) and acetic acid (2.8–24.5%), limonene (0.8–14.7%), carvol (3.8–7.1%), geranyl acetone (1.4–7.9%) and (E)-caryophyllene (3.3–8.4%), and (E)-anethole (0.6–35.0%), respectively. We assume that factors such as the manufacturing process, the storage conditions and the different geographic origin of the samples may contribute to such variability. 相似文献
107.
The distribution and the origin of carbon and nitrogen in sediments of an Italian lagoon--located north-east of Ravenna town--were investigated. From 1957 to 1976, the lagoon had been affected by a strong industrial pollution due to an important petrochemical complex. At present, industrial and domestic waste waters undergo a treatment process before being discharged into the lagoon. Sediment samples from 10 locations throughout the lagoon were analysed, in order to document the spatial and vertical distribution of C and N. Data show a very strong variability (organic carbon content varies between 8.9% and 0.14%) and the highest values were found in the immediate vicinity of the industrial discharge. Sediment organic matter shows allochthonous origin in proximity of industrial discharge and autochthonous origin in the remaining areas. 相似文献
108.
109.
Alfred Schmidpeter Angela Willhalm Jürgen Kroner Roberta O. Day Joan M. Holmes Robert R. Holmes 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):495-498
Abstract Phosphamethincyanines prepared in 1964 by Dimroth and Hoffmann were among the first compounds with two-coordinate phosphorus. They are special cases of 2-phospha-allylic cations. Simple representatives of this type become available from the reaction of imidoyl chlorides with tris(trimethylsily1)phosphane. 相似文献
110.
Dr. Alba Silipo Johan Larsbrink Roberta Marchetti Prof. Rosa Lanzetta Prof. Harry Brumer Prof. Antonio Molinaro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(42):13395-13404
The study of the interaction of glycoside hydrolases with their substrates is fundamental to diverse applications in medicine, food and feed production, and biomass‐resource utilization. Recent molecular modeling of the α‐xylosidase CjXyl31A from the soil saprophyte Cellvibrio japonicus, together with protein crystallography and enzyme‐kinetic analysis, has suggested that an appended PA14 protein domain, unique among glycoside hydrolase family 31 members, may confer specificity for large oligosaccharide fragments of the ubiquitous plant polysaccharide xyloglucan (J. Larsbrink, A. Izumi, F. M. Ibatullin, A. Nakhai, H. J. Gilbert, G. J. Davies, H. Brumer, Biochem. J. 2011 , 436, 567–580). In the present study, a combination of NMR spectroscopic techniques, including saturation transfer difference (STD) and transfer NOE (TR‐NOE) spectroscopy, was used to reveal extensive interactions between CjXyl31A active‐site variants and xyloglucan hexa‐ and heptasaccharides. The data specifically indicate that the enzyme recognizes the entire cello‐tetraosyl backbone of the substrate and product in positive enzyme subsites and makes further significant interactions with internal pendant α‐(1→6)‐linked xylosyl units. As such, the present analysis provides an important rationalization of previous kinetic data on CjXyl31A and unique insight into the role of the PA14 domain, which was not otherwise obtainable by protein crystallography. 相似文献