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排序方式: 共有11条查询结果,搜索用时 156 毫秒
1.
沈含熙  王连生 《化学学报》1983,41(8):700-708
本文研究了八种2,3,7-三羟基-9-取代荧光酮在阳离子表面活性剂存在下与锗的胶束增敏显色反应.发现水杨基萤光酮及邻硝基苯基萤光酮在强酸性介质中可以和溴化十六烷基三甲基铵形成高灵敏的胶束三元配合物.较详细地研究了用邻硝基苯基萤光酮与溴化十六烷基三甲基铵分光光度法测定微量锗的实验条件.并探讨了有关配合物的组成以及胶束增敏反应的机理.此法可不经分离,直接快速测定铅锌矿中的微量锗,结果比较满意.  相似文献   
2.
This report presents the results of a series of investigation on commercial radiation sterilization of disposable PVC infusion sets products from about fifty factories, which is based on the model of sterilization probability. According to sterilization probability, the results from the chemical and physical characteristics changes and radiation biological effects testing for its pyrogens, toxin and hemolysis reaction, the sterilization dose could be appropriately chosen.  相似文献   
3.
(CTAB+BY)体系水溶液的光谱研究   总被引:3,自引:0,他引:3  
张韫宏  梁映秋 《化学学报》1993,51(6):586-593
用UV-Vis和共振Raman光谱,研究了阳离表面活性剂溴化二六烷基三甲胺(CTAB)和对阴离子染料亮黄(BY)混合体系在水溶液中的胶束化过程,结果表明,难溶盐的形成诱导了该体系胶束的提前形成,形成的胶束使BY由酸式结构转变为碱式结构,进一步研究水溶液和胶束溶液中BY的酸碱平衡过程,发现胶束表面使BY的表观解离常数增加了两个数量级,而在胶束水溶液中,随着电解质浓度的增加,BY的表观解离常数下降,由此说明BY处于胶束的扩散层中,并导致BY结构发生变化.  相似文献   
4.
传统距离-多普勒算法中观测期间多普勒频率为常量的假设在合成孔径激光雷达系统中不再成立.根据合成孔径激光雷达回波信号模型,推导计算了振动对合成孔径激光雷达回波相位的影响.根据实际情况引入振动频率不超过500 Hz、振幅不超过0.2 mm的机载平台微振动参量,结果表明载机微振动对合成孔径激光雷达成像的方位分辨率影响很大,而对距离分辨率影响不大.采用时频分析成像方法,能够有效克服传统距离-多普勒算法对时变信号处理的局限性.分析比较Wigner-Ville分布、伪WWigner-Ville分布和平滑伪Wigner-Ville分布作为核函数的时频成像结果,均无法兼顾成像分辨率和成像效率.据此本文提出了一种基于自适应窗的联合时频成像方法,根据变异系数和变异阈值的比较自适应地调整子区域窗口大小,从而达到成像分辨率和算法效率的平衡优化.仿真结果表明,本算法对成像分辨率影响不大,成像时间减少近69.87%,适用于合成孔径激光雷达对成像高分辨率和成像效率的要求.  相似文献   
5.
《Composite Interfaces》2013,20(3):213-221
The formation of higher order aggregates in aqueous media from naturally occurring surfactants (biosurfactants) and its mechanism have been studied. A liposome (vesicle), as a kind of artificial cell, is prepared according to a newly developed microencapsulation technique from phospholipids by mimicking the molecular structure of biomembranes. Secondly, the surface active properties of alkaline salts of spiculisporic acid depend on the kinds of alkali as its gegen ions; these have been studied for the purpose of a detailed understanding of vesicle formation of the alkylamine salts of spiculisporic acid in the binary system consisting of spiculisporates and water. Thirdly, the solution behavior of the ternary system of spiculisporates-oil-water is examined. Divalent cationic salts of spiculisporic acid formed oil-in-water (O/W) emulsion gels due to ionic-bonding network formation of spiculisporates around emulsified oil droplets and these are important for their gelling properties. These gelling systems may have potential to be O/W emulsion-type paints and safe fuels.  相似文献   
6.
Salbutamol (SAL) is the most widely used β2‐agonist drug for asthma and chronic obstructive pulmonary patients, but it is also often abused as feed additive. In recent years, the abuse of SAL has led to a large number of food safety incidents. Therefore, the monitoring of SAL residues in animal products is very important. A highly selective boronate affinity magnetic adsorbent was synthesized and developed for detection of trace levels of SAL residues in pig tissue samples. The obtained Fe3O4@SiO2@FPBA(4‐formylphenylboronic acid) magnetic adsorbent showed good adsorption ability to catechol and SAL, and then it was successfully applied as special magnetic solid‐phase phase extraction adsorbent coupled with high‐performance liquid chromatography (HPLC) for simultaneous isolation and determination of cis‐diol compounds. The binding capacity of catechol and SAL reached 96 and 50 µmol/g, respectively. The method was successfully established for the detection of trace levels of SAL in pig tissue samples. The linear range extended from 0.32 to 800 µg/kg (R2 = 0.9994). The limit of detection of SAL was 0.19 µg/kg. The recoveries were satisfactory (89.5–108.0%) at three spiked levels with RSD between 2.1 and 11.3%. These results indicated that the method has potential for enrichment and detection of trace levels of SAL residual in animal food products. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
7.
The opthalmic suspension whose active compounds are antibiotic and corticosteriods, was submitted, in the final package, to radiation in a Cobalt-60 source and their stability to gamma radiation has been investigated. This procedure aims to substitute the conventional aseptic method of manufacturing and packaging for radiation sterilization. Microbiological studies have been carried out to determine the minimum absorbed dose achieving the required Sterility Assurance Level (SAL) of 10-6. The microbiological and product stability data obtained till the present time, support the use of radiation sterilization.  相似文献   
8.
张光  张振义 《化学学报》1991,49(10):993-997
本文建立了利用Rh(III)-5-Br-TAMB-CP配合物吸附波体系测定铑的电化学分析方法。研究了该体系吸附波的性质及阳离子表面活性剂CPC在体系中的作用机理。该方法灵敏度高, 选择性好, 可用于催化剂中铑的测定。  相似文献   
9.
阴/阳离子表面活性剂复配体系的中相微乳液研究   总被引:14,自引:0,他引:14  
阴离子表面活性剂双-2-乙基己基磺化琥珀酸钠(简称AOT), 和阳离子表面活性剂十六烷基三甲基溴代铵(简称CTAB), 在有醇、正辛烷、盐水存在的情况下,能形成多相微乳液。本文系统地研究了阴/阳离子表面活性剂配比、醇的种类、醇的浓度对该体系的中相微乳液的形成及特性的影响, 得到了中相微乳液的特性参数(最佳含盐量S^*, 最佳中相微乳液体积V^*, 界面张力r~E、盐宽△S等)。这些性质对与阴/阳离子表面活性剂复配体系, 三次采油及日用化工上的应用开发具有重要意义。最后还开展单独阴离子表面活性剂体系和阴/阳离子表面活性剂复配体系进行了比较, 得到一些有价值规律, 并从理论上进行了探讨。  相似文献   
10.
李明磊  吴谨  白涛  万磊  李丹阳 《中国光学》2019,12(1):130-137
为了探索大随机相位误差条件下合成孔径雷达(SAL)成像特点和规律,本文采用波长为1 550 nm的线性调频激光器建立了能够产生大的共模随机相位误差的条带模式SAL成像实验装置。利用此装置获得了不同目标回波强度下条带模式SAL成像实验数据,结合条带模式相位梯度自聚焦(PGA)多次迭代处理,获得了高分辨率SAL图像。实验发现在[-6. 45π,6. 45π]范围的大随机相位误差下,通过简单的距离压缩和方位匹配滤波,无法实现SAL图像聚焦,图像信噪比仅为3 dB。进一步采用PGA处理,就能很好地校正相位误差,得到聚焦良好的SAL图像,图像信噪比达到43 dB。实验还发现,当存在大共模随机相位误差时,PGA处理展现出非常强的鲁棒性,在回波弱到10-15W的情况下依然有效。在大相位误差存在的SAL系统(如机载SAL)中,PGA处理能有效消除相位误差,实现图像聚焦;另外,增大探测激光功率以提高成像数据信噪比,将有助于提升PGA处理效果。  相似文献   
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