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91.
M.?J.?SticklandEmail author T.?J.?Scanlon P.?Waddell J.?Fernandez-Francos E.?Blanco 《Experiments in fluids》2003,34(2):304-306
This paper describes the use of a rotating all-mirror image derotator system, high-speed video and particle image velocimetry
(PIV) to visualise and quantitatively examine the flow patterns between the blades of a centrifugal impeller. The flow field
relative to the moving centrifugal impeller is presented.
Published online: 13 December 2002 相似文献
92.
Fernández C Santos HM Ruíz-Romero C Blanco FJ Capelo-Martínez JL 《Electrophoresis》2011,32(21):2966-2974
In this work three methods to diminish the content of most highly abundant proteins in human serum have been studied and compared. Protein depletion with ACN or DTT and protein equalization with the ProteoMiner? (PM) have been assessed by 1‐D gel electrophoresis and MS. After treatment 5, 18 and 9 major proteins within the 20 most abundant proteins in serum were identified for the ACN, DTT and PM methods, respectively. The ACN method was efficient for depleting high molecular weight proteins, over 75 KDa, resulting in 10±4% (n=3) of the total protein content remaining in the depleted serum. In addition, 75% of the proteins belonging to the group of the 20 most abundant proteins were not detected, making this depletion strategy a cheap alternative to expensive commercial tools regularly used for removing high abundance proteins from serum. The ACN extract was found rich in apolipoproteins. The dithithreitol method promotes the precipitation of proteins rich in disulfide bonds, mainly albumin, with 73±7% (n=3) of the total protein content remaining in the depleted serum, which was found rich in immunoglobulins. The PM method compresses the dynamic range of the serum proteins, rendering an extract containing 16±2% (n=3) of the total initial protein content. The extract was found to be rich in both apolipoproteins and immunoglobulins. As a general rule the DTT and PM methods provide a compression of the dynamic range of serum protein concentrations while the ACN method allows an effective depletion of the protein fraction above 72 KDa. 相似文献
93.
Using an appropriate set of samples to construct the calibration set is crucial with a view to ensuring accurate multivariate calibration of NIR spectroscopic data. In this work, we developed and optimized a new methodology for incorporating physical variability in pharmaceutical production based on the NIR spectrum for the process. Such a spectrum contains the spectral changes caused by each treatment applied to the component mixture during the production process. The proposed methodology involves adding a set of process spectra (viz. difference spectra between those for production tablets and a laboratory mixture of identical nominal composition) to the set of laboratory samples, which span the wanted concentration range, in order to construct a calibration set incorporating all physical changes undergone by the samples in each step of the production process. The best calibration model among those tested was selected by establishing the influence of spectral pretreatments used to obtain the process spectrum and construct the calibration models, and also by determining the multiplying factor m to be applied to the process spectra in order to ensure incorporation of all variability sources into the calibration model. The specific samples to be included in the calibration set were selected by principal component analysis (PCA). To this end, the new methodology for constructing calibration sets for determining the Active Principle Ingredients (API) and excipients was applied to Irbesartan tablets and validated by application to the API and excipients of paracetamol tablets. The proposed methodology provides simple, robust calibration models for determining the different components of a pharmaceutical formulation. 相似文献
94.
The silylcupration of allene using a lower order silylcopper species gives an allylsilane-vinyl copper intermediate 2 which, in conjunction with an organolithium reagent, is able to participate in a one-pot multicoupling reaction with α,β-unsaturated nitriles. The scope of this tandem reaction is studied and a possible mechanism pathway is outlined. 相似文献
95.
Rueping M Haack K Ieawsuwan W Sundén H Blanco M Schoepke FR 《Chemical communications (Cambridge, England)》2011,47(13):3828-3830
The design of biologically inspired, multi-component cascade reactions enables the targeted synthesis of assorted structurally complex products. Similar to regulation in cells the reaction path is controlled by the substrate concentration and complex enantiopure products with high structural diversity are provided. 相似文献
96.
Grabow JU Mata S Alonso JL Peña I Blanco S López JC Cabezas C 《Physical chemistry chemical physics : PCCP》2011,13(47):21063-21069
Nicotine has been investigated in the gas phase and two conformational forms were characterized through their rotational spectra. Two spectroscopic techniques have been used to obtain the spectra: a new design of broadband Fourier transform microwave (FTMW) spectroscopy with an in-phase/quadrature-phase-modulation passage-acquired-coherence technique (IMPACT) and narrowband FTMW spectroscopy with coaxially oriented beam-resonator arrangement (COBRA). The rotational, centrifugal distortion and hyperfine quadrupole coupling constants of two conformers of nicotine have been determined and found to be in N-methyl trans configurations with the pyridine and pyrrolidine rings perpendicular to one another. The quadrupole hyperfine structure originated by two (14)N nuclei has been completely resolved for both conformers and used for their unambiguous identification. 相似文献
97.
In this note, we give a positive answer to a question of Dimca and Greuel about the quotient between the Milnor and Tjurina numbers of an isolated plane curve singularity in the cases of one Puiseux pair and semi-quasi-homogeneous singularities. 相似文献
98.
Positivity - We consider the question of when is every positive compact operator, between two given Banach lattices, approximable regular. An immediate consequence of our main result is that,... 相似文献
99.
100.