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1.
Kristian Hougaard Frederik D. Nielsen 《Journal of Optical and Fiber Communications Reports》2004,1(1):63-83
In this paper we will present an overview of the use
of photonic crystal fibers as fiber amplifiers. We
will describe the basic concepts of optical
amplification, and how to do numerical modelling of
such components. We will then identify advantages
and disadvantages of amplifiers based on PCF
technology compared to conventional fibers, and then
go into greater detail on some of these specific
applications, such as low pump power amplifiers, and
high-power double-clad amplifiers and lasers. 相似文献
2.
3.
Kristian K. Müller-Nedebock Shaul M. Aharoni Sam F. Edwards 《Macromolecular Symposia》1995,98(1):701-717
Networks of rigid molecules do not fit into the paradigm of classical theories of rubber elasticity. Some experimental properties of rigid polyamide networks are summarised, and the basis for a theoretical understanding of such systems is discussed and elaborated in terms of the properties such as the existence of several conformational states and twist of such network elements. 相似文献
4.
Margaux Fresnais Seda Karabulut Yasmin Abou Zeed Johannes Ungermann Julia Benzel Kristian W. Pajtler Stefan M. Pfister Walter E. Haefeli Jürgen Burhenne Rmi Longuespe 《Molecules (Basel, Switzerland)》2022,27(3)
Desorption/ionization mass spectrometry (DI-MS) approaches allow for the rapid quantification of drugs in biological matrices using assays that can be validated according to regulatory guidelines. However, specific adaptations must be applied to create reliable quantification methods, depending on the approach and instrumentation used. In the present article, we demonstrate the importance of the molecular weight, the fragmentation pattern, and the purity of the internal standard for the development of matrix-assisted laser desorption/ionization (MALDI)-ion mobility (IM)-tandem MS and MS/MS methods. We present preliminary results of method development for the quantification of selinexor in microdialysis fluids with a stable isotopically labeled internal standard. In addition, we discuss the selection of internal standards for MALDI-MS assays using different instrumentations. 相似文献
5.
A new hybrid magnetic bead separator that combines an external magnetic field with 175 μm thick current lines buried in the back side of a silicon wafer is presented. A microfluidic channel was etched into the front side of the wafer. The large cross-section of the current lines makes it possible to use larger currents and obtain forces of longer range than from thin current lines at a given power limit. Guiding of magnetic beads in the hybrid magnetic separator and the construction of a programmable microarray of magnetic beads in the microfluidic channel by hydrodynamic focusing is presented. 相似文献
6.
In this paper, we present a framework to construct general stochastic Runge–Kutta Lawson schemes. We prove that the schemes inherit the consistency and convergence properties of the underlying Runge–Kutta scheme, and confirm this in some numerical experiments. We also investigate the stability properties of the methods and show for some examples, that the new schemes have improved stability properties compared to the underlying schemes.
相似文献7.
The polynomial associated with the largest disk of stability of anm-stage explict Runge-Kutta method of orderp is unique. 相似文献
8.
Rocha-Rinza T Sneskov K Christiansen O Ryde U Kongsted J 《Physical chemistry chemical physics : PCCP》2011,13(4):1585-1589
Using advanced QM/MM methods, the surprisingly negligible shift of the lowest-lying bright electronic excitation of the deprotonated p-coumaric acid (pCA(-)) within the photoactive yellow protein (PYP) is shown to stem from a subtle balance between hypsochromic and bathochromic effects. More specifically, it is found that the change in the excitation energy as a consequence of the disruption of the planarity of pCA(-) inside PYP is nearly canceled out by the shift induced by the intermolecular interactions of the chromophore and the protein as a whole. These results provide important insights about the primary absorption and the tuning of the chromophore by the protein environment in PYP. 相似文献
9.
Lubomír Lap?ík Barbora Lap?íková Ivo Krásny Ivana Kupská Richard W. Greenwood Kristian E. Waters 《Plasma Chemistry and Plasma Processing》2012,32(4):845-858
It was found in this study that the air plasma treatment of particular kaolinite has led to the change of its wettability, which was reflected in the decreased values of water contact angles of wetting from 88.7° for virgin kaolinite to 86.3° for 30?min air plasma treated one. Plasma treated samples show higher average surface energies in the wide range of coverage regimes in comparison to the virgin samples as determined by inverse gas chromatography. Results of these measurements confirmed our assumption, that air plasma treatment activates surface energy of the crystal planes of the kaolinite as reflected in the broadened dispersive surface energy distribution after 10?min treatment time. However with prolonged 30?min treatment time the dispersive surface energy distribution profile was decreased. We assume, that the latter decrease reflects the distorsion of the crystal lattice of the kaolinite as confirmed by FTIR analysis as reflected in changes of Si?CO?CSi and Al2O?CH characteristic absorption bands. Calculated dispersive surface free energy for 24?% surface coverage was increased from original 35?mJ/m2 to 40.3 and 40.8?mJ/m2 for 10 and 30?min treatment times. There were determined yield locus and flow function dependencies at different stress levels for virgin and different time plasma treated samples (flow index??ff c , effective angle of internal friction???? e , unconfined yield strength???? c ). It was found that by plasma treatment the character of the flow was shifting from region of very cohesive (ff c ?=?2.39) to the cohesive (ff c ?=?3.19). For untreated samples effective angle of internal friction was decreased with increasing applied consolidation stress, while for plasma treated kaolinite it was increased. 相似文献