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51.
Surface plasmon resonance (SPR) sensors have been a mature technology for more than two decades now, however, recent investigations show continuous enhancement of their sensitivity and their lower detection limit. Together with the recent investigations in localized SPR phenomena, extraordinary optical transmission through nanoapertures in metals, and surface‐enhanced spectroscopies, drastic developments are expected to revolutionize the field of optical biosensing. Sensitivity‐enhancement (SE) techniques are reviewed focusing both on the physical transduction mechanisms and the system performance. In the majority of cases the SE is associated with the enhancement of the electromagnetic field overlap integral describing the interaction energy within the analyte. Other important mechanisms are the interaction between plasmons and excitons and between the analyte molecules and the metal surface. The lower detection limit can be reduced significantly if systems with high signal‐to‐noise ratio are used such as common‐path interferometry, ellipsometry or polarimetry systems. 相似文献
52.
In this paper, we are interested in the Laguerre hypergroup $\mathbb{K} = [0,\infty ) \times \mathbb{R}$ which is the fundamental manifold of the radial function space for the Heisenberg group. So, we consider the generalized shift operator generated by the dual of the Laguerre hypergroup which can be topologically identified with the so-called Heisenberg fan, the subset of ?2: $$\bigcup\limits_{j \in \mathbb{N}} {\left\{ {(\lambda ,\mu ) \in \mathbb{R}^2 :\mu = \left| \lambda \right|(2j + \alpha + 1),\lambda \ne 0} \right\} \cup \left\{ {(0,\mu ) \in \mathbb{R}^2 :\mu \geqslant 0} \right\}} ,$$ by means of which the maximal function is investigated. For 1 < p ?? ??, the L p ( )-boundedness and weak L 1( )-boundedness result for the maximal function is obtained. 相似文献
53.
Rahmouni Atef 《Mediterranean Journal of Mathematics》2013,10(1):333-351
In this paper, we give analogues of local uncertainty inequality on ${\mathbb{R}^n}$ for stratified Laguerre hypergroup, connected with the spectral analysis of a given homogeneous sublaplacian L, also indicate how local uncertainty inequalities imply global uncertainty inequalities. It would be interesting to note that we deduce the local uncertainty inequalities for the radial functions on the Heisenberg group. Finally, we extend Heisenberg-Pauli-Weyl uncertainty inequality by ultracontractive properties of the semigroups generated by the differential operator and on the estimate on the heat kernel. 相似文献
54.
In this work, we present a simple method for absolute quantification of plasma vitellogenin from both rainbow trout and Atlantic salmon. Plasma samples obtained from control and beta-estradiol induced fish were digested with trypsin. A characteristic 'signature peptide' was selected and analyzed by high performance liquid chromatography (HPLC) coupled to an electrospray quadrupole-time-of-flight tandem mass spectrometer, using a deuterated homolog peptide as an internal standard. The hybrid tandem mass spectrometer was operated in a 'pseudo' selected reaction-monitoring mode in which three diagnostic product ions were monitored for identification and quantification purposes. The reproducibility (coefficient of variation approximately 5%) and sensitivity (limit of quantification (LOQ) of 0.009 mg/ml) achieved by this simple assay allow it to be considered as an alternative to immunological assays. 相似文献
55.
We present an optical model based on Green’s function to investigate the effect of using single-wall carbon nanotube (SWCNT)
as anode for infrared quantum dot light-emitting devices (IR QD-LEDs). To the best of our knowledge, there is no report in
using SWCNT as anode in IR QD-LEDs. We have studied the emitted power distribution among the different optical modes (external
propagating mode (photon outcoupling efficiency), substrate, anode/organics, and surface plasmon modes (SP)), angular intensity
distribution, viewing angle effect on the optical characteristics, and the emission spectral characteristics. We have found
that the light outcoupling efficiency of IR QD-LEDs based on SWCNT as anode was increased nearly by a factor of 4 relative
to that one based on indium-tin oxide (ITO). We also investigated the effect of using different cathode materials on the optical
characteristics of IR QD-LEDs. 相似文献
56.
57.
Intermolecular cyclization of pyrimidinethiol 1 with ethyl chloroacetate and chloroacetonitrile furnished thieno[2,3-d]pyrimidines 2a,b . Hydrazinolysis of o-aminoester 2a gave acid hydrazide 3, which was cyclized with various electrophilic reagents including formic acid, triethyl orthoformate, acetic anhydride, p-chlorobenzaldehyde then triethyl orthoformate, carbon disulfide, and acetylacetone affording thienopyrimidine derivatives 4 to 10 . Another thienopyrimidine series could be obtained via treatment of o-aminocarbonitrile 2b with a variety of reagents giving derivatives 11 to 17 . The fluorescent measurements for a group of the synthesized compounds at room temperature demonstrated high fluorescent properties. 相似文献
58.
Somaya E. Abdel Rahman Ahmed M. Naglah Mohamed A. Al-Omar Atef Kalmouch Rasha A. Amin 《Research on Chemical Intermediates》2014,40(4):1691-1702
A series of erythropoietin hormone analogues (1–9) were synthesized by a modern method, microwave-assisted modified solid-phase peptide synthesis, on polystyrene polyethylene glycol graft copolymer. Peptide 9 was cleaved from the polymer to give peptide 10. Measurement of haematological data for analogue 10 gave good results comparable with those of the original hormone. The structures of the new peptides were confirmed by amino acid analysis and use of spectroscopic evidence. 相似文献
59.
60.