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1.
The possibilities of controlling the laser beam properties by a deformable mirror introduced into the laser optical cavity
were studied theoretically and experimentally. The experiments were performed under conditions of an industrial high power
transverse flow cw CO2 laser operating with a stable resonator of a folded configuration. A deformable bimorph mirror of a surface profile controlled
by the voltage applied to the mirror electrodes is implemented to the laser system as a back cavity mirror or as a one of
the inner folding mirrors. The near-and far-field characteristics of the laser beam versus the resonator configuration controlled
by the changes of the focal length of the deformable mirror are discussed in the paper. The analysis reveals that the resonator
with an inner deformable mirror is much more sensitive to the mirror curvature variations than the resonator in which the
deformable mirror is used as a back cavity mirror. The presented results show that dynamic and controllable changes in the
resonator properties result in the controlled modification and optimisation of the laser output power and spatial parameters
of the laser radiation. 相似文献
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3.
C. Thai-HoangN. Nguyen-Thanh H. Nguyen-Xuan T. Rabczuk 《Applied mathematics and computation》2011,217(17):7324-7348
This paper presents an alternative alpha finite element method using triangular meshes (AαFEM) for static, free vibration and buckling analyses of laminated composite plates. In the AαFEM, an assumed strain field is carefully constructed by combining compatible strains and additional strains with an adjustable parameter α which can produce an effectively softer stiffness formulation compared to the linear triangular element. The stiffness matrices are obtained based on the strain smoothing technique over the smoothing domains and the constant strains on triangular sub-domains associated with the nodes of the elements. The discrete shear gap (DSG) method is incorporated into the AαFEM to eliminate transverse shear locking and an improved triangular element termed as AαDSG3 is proposed. Several numerical examples are then given to demonstrate the effectiveness of the AαDSG3. 相似文献
4.
Heterogeneities in the cell membrane due to coexisting lipid phases have been conjectured to play a major functional role in cell signaling and membrane trafficking. Thereby the material properties of multiphase systems, such as the line tension and the bending moduli, are crucially involved in the kinetics and the asymptotic behavior of phase separation. In this Letter we present a combined analytical and experimental approach to determine the properties of phase-separated vesicle systems. First we develop an analytical model for the vesicle shape of weakly budded biphasic vesicles. Subsequently experimental data on vesicle shape and membrane fluctuations are taken and compared to the model. The parameters obtained set limits for the size and stability of nanodomains in the plasma membrane of living cells. 相似文献
5.
On the isobaric space of 25‐hydroxyvitamin D in human serum: potential for interferences in liquid chromatography/tandem mass spectrometry,systematic errors and accuracy issues 下载免费PDF全文
6.
Schwaighofer A Schroeter T Mika S Hansen K Ter Laak A Lienau P Reichel A Heinrich N Müller KR 《Journal of chemical information and modeling》2008,48(4):785-796
Metabolic stability is an important property of drug molecules that should-optimally-be taken into account early on in the drug design process. Along with numerous medium- or high-throughput assays being implemented in early drug discovery, a prediction tool for this property could be of high value. However, metabolic stability is inherently difficult to predict, and no commercial tools are available for this purpose. In this work, we present a machine learning approach to predicting metabolic stability that is tailored to compounds from the drug development process at Bayer Schering Pharma. For four different in vitro assays, we develop Bayesian classification models to predict the probability of a compound being metabolically stable. The chosen approach implicitly takes the "domain of applicability" into account. The developed models were validated on recent project data at Bayer Schering Pharma, showing that the predictions are highly accurate and the domain of applicability is estimated correctly. Furthermore, we evaluate the modeling method on a set of publicly available data. 相似文献
7.
Schwaighofer A Schroeter T Mika S Laub J ter Laak A Sülzle D Ganzer U Heinrich N Müller KR 《Journal of chemical information and modeling》2007,47(2):407-424
Accurate in silico models for predicting aqueous solubility are needed in drug design and discovery and many other areas of chemical research. We present a statistical modeling of aqueous solubility based on measured data, using a Gaussian Process nonlinear regression model (GPsol). We compare our results with those of 14 scientific studies and 6 commercial tools. This shows that the developed model achieves much higher accuracy than available commercial tools for the prediction of solubility of electrolytes. On top of the high accuracy, the proposed machine learning model also provides error bars for each individual prediction. 相似文献
8.
Timon Geib Lekha Sleno Rabea A. Hall Caroline S. Stokes Dietrich A. Volmer 《Journal of the American Society for Mass Spectrometry》2016,27(8):1404-1410
We describe a systematic comparison of high and low resolution LC-MS/MS assays for quantification of 25-hydroxyvitamin D3 in human serum. Identical sample preparation, chromatography separations, electrospray ionization sources, precursor ion selection, and ion activation were used; the two assays differed only in the implemented final mass analyzer stage; viz. high resolution quadrupole-quadrupole-time-of-flight (QqTOF) versus low resolution triple quadrupole instruments. The results were assessed against measured concentration levels from a routine clinical chemiluminescence immunoassay. Isobaric interferences prevented the simple use of TOF-MS spectra for extraction of accurate masses and necessitated the application of collision-induced dissociation on the QqTOF platform. The two mass spectrometry assays provided very similar analytical figures of merit, reflecting the lack of relevant isobaric interferences in the MS/MS domain, and were successfully applied to determine the levels of 25-hydroxyvitamin D for patients with chronic liver disease. 相似文献
9.
J. Stańco Z. Rozkwitalski G. Sliwiński J. Konefał P. Kukiełło G. Rabczuk R. Zaremba 《Applied physics. B, Lasers and optics》1986,41(4):245-250
A high-power CO2 laser for investigations on materials processing is described. Measurements of the output characteristics of the laser are discussed on the basis of an adequate model. 相似文献
10.
The two-component solid—liquid phase eqilibria systems of some methyl derivatives of naphthalene with 2,4,6-trinitrophenol and 2,4,6-trinitrotoluene have been examined by DTA. All systems contain molecular complexes with 11 compositions.
Zusammenfassung Zweikomponentige Fest-Flüssig-Phasengleichgewichtssysteme von einigen Methylderivaten von Naphthalen mit 2,4,6-Trinitrophenol und 2,4,6-Trinitrotoluol wurden mittels DTA untersucht. Alle Systeme enthalten Molekülkomplexe der Zusammenserzung 11.
2,4,6- 2,4,6-. 11.相似文献