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A. Latham J. Allison I. Booth B. Dickinson S.R. Hill M. Ibbotson R. Lawson H.E. Mills K. Stephens R.J. Thompson O. Vapenikova D. Baxter D.C. Darvill M. Davenport F. Foster G. Hughes J.V. Morris J. Wright W.R. Rawlinson 《Nuclear Physics B》1981,189(1):1-14
Data are presented for the reaction ep → epπ0 at a nominal momentum transfer squared of 1.0 (GeV/c)2. The data were obtained using an extracted electron beam from NINA and two magnetic spectrometers for coincidence detection of the electron and proton. Differential cross sections have been measured for isobar masses in the range 1.19–1.73 GeV/c2. 相似文献
13.
Z.M. Babar Wan Mohd Azizi Solachuddin JA Ichwan Qamar Uddin Ahmed Abul Kalam Azad Imranul Mawa 《Natural product research》2019,33(15):2266-2270
The current study provides a way of extraction for both active NSO and WSE from Nigella sativa seeds using 98% methanol. About 1?kg of ground seeds was macerated by 1:2.5 w/v (g/mL) for 72?hours. After rotary evaporation and 7 days of continuous drying and chilling at 50 and 4?°C, NSO and WSE were obtained at the same instant. Solubility tests of 24 solvents and 11 thin layer chromatographic analyses while 2, 2-diphenyl-1-picrylhydrazyl free radical scavenging assay of NSO (73.66) , WSE (33.32) and NSO?+?WSE (78.22) against ascorbic acid (IC50?=?4.28?mg/mL) was performed. WSE was found to be highly soluble in water and 5% NaOH exhibiting the same Rf value of 0.95 for EtOH:DMSO (9:1) against the honey. WSE has revealed more than twofold higher anti-oxidant activity than others. Formulation of WSE with Tualang honey may provide better targeted hydrophilic drug delivery systems. 相似文献
14.
Sonia A Vanderby Michael W Carter Tim Latham Chris Feindel 《The Journal of the Operational Research Society》2014,65(9):1325-1335
Due to the high costs and lengthy lead times involved with training health human resources such as physicians and surgeons, combined with the serious burden borne by the general population when health care provider shortages occur, advance planning of resource requirements is critical. This is particularly true in light of current demographic trends and Canada’s ageing population, which will potentially increase demand for health care providers in the future while also leading to the retirement of many of the providers currently practicing. The purpose of this research was to develop a model simulating the workforce within a single specialty at a national level, which includes students training to enter the profession, providing a tool that would help to inform future resource planning. We present the details of this model, developed using system dynamics modelling, and demonstrate it using the example of cardiac surgeons in Canada. 相似文献
15.
In the drive for continuous improvement in safety and control, the international regulations which govern the shipment of radioactive materials are being extended and updated. This will have an effect on the way in which Co-60 is transported to and from radiation processing plants. The nature of the regulatory changes is explored in this paper and the effect on users is discussed 相似文献
16.
Levy JN Latham CM Roisin L Kandziora N Di Fruscia P White AJ Woodward S Fuchter MJ 《Organic & biomolecular chemistry》2012,10(3):512-515
A synthetic route towards a number of novel IBiox N-heterocyclic carbene (NHC) ligands has been developed. The resulting ligands have restricted flexibility and high steric demand. Preliminary studies have shown these ligands to give high levels of asymmetric induction in the copper-free allylic alkylation of cinnamyl bromide. 相似文献
17.
A. Munjiza J. Xiang X. Garcia J.P. Latham G.G. Schiava D'Albano N.W.M. John 《Particuology》2010,(2):100-105
In 1989 work began on merging finite and discrete elements. During 1990 algorithmic solutions for the new combined method were developed, together with a C-based implementation known as the Y code. In 2004 these developments and implementations were published as a textbook. Queen Mary University of London ~QMUL) and Imperial College are currently engaged in a research project to make Y codes in both 2D and 3D available in Open Source format and with mainly geoscience problems in mind. The result is a set of Open Source tools for Geoscience (VGW), key components of which are summarised in this paper, together with illustrative range of simulation results. 2009 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved. 相似文献
18.
Round C. I. Williams C. D. Latham K. Duke C. V. A. 《Journal of Thermal Analysis and Calorimetry》2000,63(2):329-338
The synthesis of pure silica ZSM-5 has been modified to produce highly crystalline material in the protonated form, necessary
for catalytic activity, directly from a low water fluoride gel. Tetrahedrally co-ordinated divalent species of nickel and
copper have been synthesised as salts of large organic cations and increasing mole fractions incorporated into the zeolite
gels. The products have been analysed and characterised using simultaneous thermogravimetric and derivative thermogravimetric
analysis (TG-DTG). The thermal decomposition under nitrogen of the metal associated cations, tetraethylammonium (TEA+), occluded within the zeolite channels is indicative and characteristic of the incorporation of heteroatoms into the zeolite
framework. Anomalous losses in the systems can be explained by Jahn–Teller distortions. The mass losses increased with increased
metal loading and were consistent with those reported in full water system, analysis also confirmed that the material was
hydrophobic and thermally stable.
Analysis by X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray fluorescence (XRF), Fourier transform infrared
spectroscopy (FTIR) and Atomic Absorption Spectroscopy (AAS) has confirmed the reliability of TG-DTG as a diagnostic tool.
The maximum levels of substitution achieved were (mass%) Ni 3.93 and Cu 4.38.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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20.
P. E. Latham V. L. Granatstein Y. Carmel 《International Journal of Infrared and Millimeter Waves》1993,14(6):1217-1227
For imaging radar and for satelitte and space communication (e.g. NASA's deep space network), it is important that the bandwidth be as large as possible. Here we derive a formalism for computing the phase locking bandwidth that can be achieved in a gyrotron oscillator while varying the beam voltage. As an example, a second harmonic TE02/03 gyrotron is considered. For this device, the effective bandwidth can be increased by a factor of about 3 compared with the fixed voltage case by allowing the beam voltage to change together with the input locking signal. 相似文献