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991.
A novel method using liquid chromatography coupled to electrospray ionization mass spectrometry (LC-ESI-MS) has been optimized and established for the qualitative and quantitative analysis of ten active phenolic compounds originating from the pigeon pea leaves and a medicinal product thereof (Tongluo Shenggu capsules). In the present study, the chromatographic separation was achieved by means of a HiQ Sil C18V reversed-phase column with a mobile phase consisting of methanol and 0.1% formic acid aqueous solution. Low-energy collision-induced dissociation tandem mass spectrometry (CID-MS/MS) using the selected reaction monitoring (SRM) analysis was employed for the detection of ten analytes which included six flavonoids, two isoflavonoids and two stilbenes. All calibration curves showed excellent coefficients of determination (r(2) ≥ 0.9937) within the range of tested concentrations. The intra- and inter-day variations were below 5.36% in terms of relative standard deviation (RSD). The recoveries were 95.08-104.98% with RSDs of 2.06-4.26% for spiked samples of pigeon pea leaves. The method developed was a rapid, efficient and accurate LC-MS/MS method for the detection of phenolic compounds, which can be applied for quality control of pigeon pea leaves and related medicinal products. 相似文献
992.
<正>A relatively high predetermined crystallization temperature(135℃) was chosen to grow well developed iPP spherulites,then the partial melting was carried out at a temperature of 165℃,where the preformed spherulites were seen to only decrease their size but not completely melted.The crystallization behavior of partially melted isotactic polypropylene (iPP) has been carefully examined by different scanning calorimetry(DSC) and polarized light microscopy(PLM).The experimental results show that at a special annealing temperature(165℃) the melting behavior of iPP includes two parts with different mechanism,one part is the melting of iPP spherulite outside,another is the partial lamellae perfection during longer annealing time in the unmelted spherulite.The conformational orders of the iPP melt decrease with the increase of the annealing temperature. 相似文献
993.
994.
Zhang C. P. Hao T. L. Chen P. Liang J. Wang C. Z. Kang H. X. Gao R. L. Fu X. B. 《Laser Physics》2011,21(12):2122-2127
The aim of this paper is to study the effect of low-level laser irradiation (LLLI) on proliferation of myoblasts in culture.
Myoblasts derived from rat skeletal muscle were irradiated by He-Ne laser with different doses. Compared with nonirradiated
control group, the number of myoblasts increased when the cells in normal culture conditions were exposed to the laser of
specific energy density. The amount of cells with proliferating cell nuclear antigen (PCNA) positive expression and the 5-bromo-2′-deoxyuridine
(BrdU) incorporation rate after laser irradiation were also higher than that of the control group, suggesting that LLLL at
certain doses can effectively enhance myoblasts growth activity in vitro. This study firstly demonstrated that stimulating
myoblasts to enter into proliferative stage from initial resting state was an important mechanism of regeneration and repair
of injured skeletal muscle promoted by LLLI in clinical treatment. 相似文献
995.
We report a continuous-wave (CW) coherent green radiation at 532 nm by intracavity frequency doubling generation of 1064 nm
Nd:Gd0.18Y0.82VO4 laser. With incident pump power of 18.2 W, output power of 1.08 W at 532 nm has been obtained using a 5 mm-long KTP crystal.
The optical conversion efficiency was up to 5.9%. At the output power level of 1.08 W, the output stability is better than
5%. The beam quality M2 values were equal to 1.26 and 1.12 in X and Y directions, respectively. 相似文献
996.
Diode-pumped Pr<Superscript>3+</Superscript>:YAlO<Subscript>3</Subscript>/LBO violet laser at 374 nm
We report a diode-pumped Pr3+:YAlO3 laser emitting at 747 nm. A power of 232 mW at 747 nm has been achieved in continuous-wave operation with a diode emitting
2 W at 448 nm. Furthermore, intracavity second-harmonic generation in continuous-wave mode has also been demonstrated with
a power of 52 mW at 374 nm by using a LBO nonlinear crystal. The fluctuation of the violet output power was better than 2.3%.
The beam quality M
2 value is 2.2. 相似文献
997.
A dual-wavelength continuous-wave (CW) diode end-pumped gadolinium scandium aluminum garnet (Nd:GSAG) laser that generates
simultaneous laser action at the wavelengths 1061 and 942 nm is demonstrated. A total output power of 589 mW (476 mW at 1061
nm and 113 mW at 942 nm) for the dual-wave-length was achieved at the incident pump power of 18.2 W. The M
2 values for 942 and 1061 nm lights were found to be around 1.18 and 1.37, respectively. 相似文献
998.
999.
Melodic contour identification was measured in cochlear implant (CI) and normal-hearing (NH) subjects for piano samples processed by four bandpass filters: low (310-620 Hz), middle (620-2480 Hz), high (2480-4960 Hz), and full (310-4960 Hz). NH performance was near-perfect for all filter ranges and much higher than CI performance. The best mean CI performance was with the middle frequency range; performance was much better for some CI subjects with the middle rather than the full filter. These results suggest that acoustic filtering may reduce potential mismatches between fundamental frequencies and harmonic components thereby improving CI users' melodic pitch perception. 相似文献
1000.
Li Y Zhang G Kang HY Liu S Han D Fu QJ 《The Journal of the Acoustical Society of America》2011,129(6):EL242-EL247
Cochlear implant (CI) users' speech understanding may be influenced by different speaking styles. In this study, speech recognition was measured in Mandarin-speaking CI and normal-hearing (NH) subjects for sentences produced according to four styles: slow, normal, fast, and whispered. CI subjects were tested using their clinical processors; NH subjects were tested while listening to a four-channel CI simulation. Performance gradually worsened with increasing speaking rate and was much poorer with whispered speech. CI performance was generally similar to NH performance with the four-channel simulation. Results suggest that some speaking styles, especially whispering, may negatively affect Mandarin-speaking CI users' speech understanding. 相似文献