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51.
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Yang Z Chak P Bristow AD van Driel HM Iyer R Aitchison JS Smirl AL Sipe JE 《Optics letters》2007,32(7):826-828
Highly efficient second-harmonic generation can be achieved by harnessing resonance effects in microring resonator structures. We propose an angular quasi-phase-matching scheme based on the position dependence of polarization inside the ring resonator. 相似文献
54.
Here we describe a non-traditional method to identify cancerous human cervical epithelial cells in a culture dish based on physical adhesion between silica beads and cells. It is a simple optical fluorescence-based technique which detects the relative difference in the amount of fluorescent silica beads physically adherent to surfaces of cancerous and normal cervical cells. The method utilizes the centripetal force gradient that occurs in a rotating culture dish. Due to the variation in the balance between adhesion and centripetal forces, cancerous and normal cells demonstrate clearly distinctive distributions of the fluorescent particles adherent to the cell surface over the culture dish. The method demonstrates higher adhesion of silica particles to normal cells compared to cancerous cells. The difference in adhesion was initially observed by atomic force microscopy (AFM). The AFM data were used to design the parameters of the rotational dish experiment. The optical method that we describe is much faster and technically simpler than AFM. This work provides proof of the concept that physical interactions can be used to accurately discriminate normal and cancer cells. 相似文献
55.
King'ondu CK Iyer A Njagi EC Opembe N Genuino H Huang H Ristau RA Suib SL 《Journal of the American Chemical Society》2011,133(12):4186-4189
Short reaction times and morphology control in the synthesis of inorganic materials under nonthermal conditions remain a challenge. Herein we report a rapid, self-templating, and nonthermal method based on ultraviolet light to prepare metal oxide hierarchical structures. With this method, the morphology of the metal oxides was controlled readily without using templates. 相似文献
56.
Zou J Martin AD Zdyrko B Luzinov I Raston CL Iyer KS 《Chemical communications (Cambridge, England)》2011,47(18):5193-5195
p-Phosphonic acid calix[4]arenes render high stability to exfoliated graphenes in water. These calix[4]arenes modified graphenes can be used as highly effective substrates to nucleate ultra-small Pd nanoparticles, which in turn serve as galvanic reaction templates for the generation of high density 2D arrays of Pt nanoparticles. 相似文献
57.
Martin AD Boulos RA Iyer KS Sobolev AN Bond CS Atwood JL Dalgarno SJ Raston CL 《Chemical communications (Cambridge, England)》2011,47(35):9882-9884
Hirshfeld surface analysis of the 'ordered' inner phase of the molecular capsule complex, [(chloroform)(6)@C-n-butylpyrogallol[4]arene)(6)], provides insight into the intermolecular contacts and orientation of the solvent molecules. Molecular simulations show that adding two or three hydrogen molecules to the six solvent molecules is energetically favoured, and this correlates with NMR studies. 相似文献
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We present a simple method involving a rotating tube processor to fabricate ultrafine crystalline drug nanoparticles under microfluidic continuous flow with precise control over particle size, with significantly enhanced dissolution of the drug. 相似文献
60.
J. T. Kunjappu A. J. Singh R. M. Iyer 《Journal of photochemistry and photobiology. A, Chemistry》1987,41(1)
Improved lasing efficiency and long-term photostability of laser dye 7-amino-4-methylcoumarin (C120) has been demonstrated in zone-refined material. Among the impurities found segregated, a high molecular weight compound, 7-acetylamino-4-methylcoumarin, was identified by mass spectrometry. Melting and spectral characteristics of the zone-melted fractions showed the migration of impurities to be in the direction of the zone movement. 相似文献