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31.
Duy-Khiem Nguyen Chau Ha-Thu Ngoc Le Phuong Thi Nguyen 《Green Chemistry Letters and Reviews》2014,7(2):167-173
A novel and time-saving method to prepare a Brønsted acidic ionic liquid, 1-carboxymethyl-3-methylimidazolium hydrogen sulfate ([CMI][HSO4]), in high yield and purity was performed under microwave irradiation. The ionic liquid showed an incomparable catalytic efficiency in the microwave-accelerated esterification of arenecarboxylic acids. Moreover, its ability of being recovered and reused many times without loss of activity has made [CMI][HSO4] more favorable from the viewpoint of green chemistry. 相似文献
32.
In this Letter, we demonstrate that electron spin can influence near-field mediated light propagation through a dense ensemble of subwavelength bimetallic ferromagnetic/nonmagnetic microparticles. In particular, we show that ferromagnetic particles coated with nonmagnetic metal nanolayers exhibit an enhanced magnetic field controlled attenuation of the electromagnetic field propagated through the sample. The mechanism is related to dynamic, electromagnetically induced electron spin accumulation in the nonmagnet. The discovery of an electron spin phenomenon in the light interaction with metallic particles opens the door to the marriage of spintronic and plasmonic technologies and could pave the way for the development of light-based devices that exploit the electron spin state. 相似文献
33.
34.
Wei-Gang Hu Scott Jager Damon Chau Dave Mah Les P. Nagata 《Applied biochemistry and biotechnology》2010,160(4):1206-1216
In order to develop a recombinant full-length human anti-botulinum neurotoxin A (BoNT/A) antibody, human peripheral blood
mononuclear cells (PBMC) were collected from three healthy volunteers and induced for BoNT/A-specific immune response by in
vitro immunization. The genes encoding human Fd fragment, consisting of antibody heavy chain variable region and constant
region 1 with the genes encoding antibody light chain, were cloned from the immunized PBMC. Afterwards, one combinatory human
antigen-binding fragment (Fab) library was constructed using a lambda phage vector system. The size of the constructed library
was approximately 105
Escherichia coli transformants. After screening the library by BoNT/A antigen using a plaque lifting with immunostaining approach, 55 clones
were identified as positive. The Fab gene of the most reactive clone exhibiting particularly strong BoNT/A binding signal
was further subcloned into a full-length human IgG1 antibody gene template in an adenoviral expression vector, in which the
heavy and light chains were linked by a foot-and-mouth-disease virus-derived 2A self-cleavage peptide under a single promoter.
After the full-length human IgG1 was expressed in mammalian cells and purified with protein L column, sodium dodecyl sulfate-polyacrylamide
gel electrophoresis showed that the heavy and light chains of the antibody were cleaved completely. The affinity expressed
as the dissociation constant (K
d) for the recombinant human antibody to bind to BoNT/A was determined by indirect enzyme-linked immunosorbent assay and results
confirmed that the recombinant full-length human antibody retained BoNT/A-binding specificity with K
d value of 10−7 M. 相似文献
35.
Wan YS Chau JL Gavriilidis A Yeung KL 《Chemical communications (Cambridge, England)》2002,(8):878-879
A zeolite-based microengineered reactor was fabricated and tested for 1-pentene epoxidation over titanium silicalite-1 (TS-1) catalyst, which has been selectively incorporated within the microreactor channel using a new synthesis procedure. 相似文献
36.
The determinatin of the concentration of major steel forming elements in 2–5 g steel samples by PGAA and reference to synthetic standard or single comparator is presented. The relative standard deviation is approximately 5%. The analysis time is about 60 min per sample. 相似文献
37.
38.
Interferometry is introduced for the first time to the study of Kerr magneto-optic effects. A polarized interferometer is used in direct measurement of the phase relationship between the two Kerr components from the head-on domains in a magnetic thin film. 相似文献
39.
A thin-beam holographic reconstruction technique to study the 3-D refractive index field of a phase object is described. The advantages and drawbacks of this method are discussed. 相似文献
40.
Fan Gong Yi-Zeng Liang Qing-Song Xu Foo-Tim Chau King-Man Ng 《Analytica chimica acta》2001,450(1-2):99-114
In this paper, a novel criterion named the overlap index (OVI) has been proposed to evaluate the separation quality in two-dimensional hyphenated chromatography. This criterion, which is obtained from the maximum value of the Gram determinant constructed by the key spectra, can reveal the degree of two-dimensional hyphenated chromatographic separation. The key spectra are selected based on the so-called D-optimal criterion. According to its geometrical sense meaning the volume spanned by the constructed vectors, OVI criterion can practically reflect the overlap degree of chromatographic peaks. The OVI criterion is further interpreted by comparing the resolution of two-dimensional data into pure chromatograms and spectra. The successful application of this OVI criterion to both of simulated two-dimensional hyphenated data and the real case in analyzing the six reference phenolic compounds from Ginkgo biloba L-leaves shows its reliability and practicality. 相似文献