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301.
302.
P. M. Larionov A. N. Malov A. M. Orishich V. S. Shchukin 《Journal of Applied Spectroscopy》1997,64(4):557-559
Investigations of laser-induced fluorescence spectra for human cardiac valve tissue with calcinosis are performed as compared
to similar spectra of bone and myocardial tissue of an animal that are excited by an excimer laser with a 248-nm wavelength.
It is shown that a healthy tissue has a laser-induced fluorescence maximum in the region of 300–400 nm which corresponds to
protein tissue luminescence. For tissue affected by calcinosis, the laser-induced fluorescence spectra differ significantly
from the spectra of healthy tissue and have a maximum in the region of 400–500 nm. The obtained results offer the prospects
for using laser-induced fluorescence to diagnose tissue with calcinosis in open-heart surgery.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 4, pp. 539–541, July–August, 1997. 相似文献
303.
Robert J. Maxwell Owen W. Parks Edwin G. Piotrowski 《Journal of separation science》1992,15(12):807-811
A novel integral restrictor–collector has been designed for use with a conventional supercritical fluid extraction (SFE) apparatus. The assembly reduces the path length between a micrometering valve and collector (a solid phase extraction (SPE) column), obviating the need for the complicated tubing and connectors usually associated with such devices. Also described is a heating-block assembly which encases the micrometering valve and provides uniform heating of the valve during extraction. The valve–SPE column assembly was part of a system used to perform the first reported SFE multi-residue drug recovery from fortified liver. Extractions used carbon dioxide pressurized to 690 bar as the supercritical fluid. Flow rates of expanded gas through the SPE columns were 3–4 L/min with concomitant quantitative trapping of the analytes on the sorbent bed. After SFE the three nitrobenzamide antimicrobial drug residues from the liver were eluted from the SPE columns by off-line analysis. The results demonstrated that losses of trace level analytes in tissue may be significantly reduced by including an integral metering valve-collector assembly as part of the SFE apparatus. 相似文献
304.
二维彩色彩虹像面全息图记录的一种新方法 总被引:4,自引:2,他引:2
本文提出了利用液晶光阀和单色激光进行彩色全息图记录的方法.借助于液晶光阀非相干-相干转换的功能,采用新的彩虹全息术,获得了记录于同一块干版上的原彩色目标由红、绿、篮三色所成的三个基色彩虹全息像.用白光透射再现,得到原彩色图的真彩色全息像.这种方法是液晶光阀、条形散斑屏在图像处理中的一种特殊应用. 相似文献
305.
本文在以波长编码实现双极光神经网络的方案基础上,对表示加权求和正、负值的两组光.点,通过在光寻址液晶光阀的相应位置加上不同.的偏置,使其分别工作在正、反态,从而实现对代表正、负值的光强的调制.然后利用光栅的移位作用,把各组的两个光点叠加到一起,其合光强即是所期望的加权求和正、负值的相减结果.通过调整液晶光阀的工作参数,得到了理想输入输出响应曲线;并用光栅实现了移位,从而在实验上验证了该方案的可行性. 相似文献
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308.
Xiu-Feng Han 《中国物理 B》2022,31(11):117504-117504
In this review, the recent developments in microelectronics, spintronics, and magnonics have been summarized and compared. Firstly, the history of the spintronics has been briefly reviewed. Moreover, the recent development of magnonics such as magnon-mediated current drag effect (MCDE), magnon valve effect (MVE), magnon junction effect (MJE), magnon blocking effect (MBE), magnon-mediated nonlocal spin Hall magnetoresistance (MNSMR), magnon-transfer torque (MTT) effect, and magnon resonant tunneling (MRT) effect, magnon skin effect (MSE), etc., existing in magnon junctions or magnon heterojunctions, have been summarized and their potential applications in memory and logic devices, etc., are prospected, from which we can see a promising future for spintronics and magnonics beyond micro-electronics. 相似文献
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310.
We have developed a simple and low-cost flow injection system coupled to a quadruple ICP-MS for the direct and continuous determination of multi-element in microdialysates. To interface microdialysis sampling to an inductively coupled plasma mass spectrometer (ICP-MS), we employed 3D printing to manufacture an as-designed sample load/inject valve featuring an in-valve sample loop for precise handling of microliter samples with a dissolved solids content of 0.9% NaCl (w/v). To demonstrate the practicality of our developed on-line system, we applied the 3D printed valve equipped a 5-μL sample loop to minimize the occurrence of salt matrix effects and facilitate an online dynamic monitoring of extracellular calcium and zinc ions in living rat brains. Under the practical condition (temporal resolution: 10 h−1), dynamic profiling of these two metal ions in living rat brain extracellular fluid after probe implantation (the basal values for Ca and Zn were 12.11 ± 0.10 mg L−1 and 1.87 ± 0.05 μg L−1, respectively) and real-time monitoring of the physiological response to excitotoxic stress elicited upon perfusing a solution of 2.5 mM N-methyl-d-aspartate were performed. 相似文献