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1.
<正> 光敏氧化效率是由敏化剂分子吸收光量子数及其产生单重态氧的量子产率决定的,这要求敏化剂的吸收光谱同光源的发射光谱很好地匹配。本文报道竹红菌甲素匹配高压钠灯有效地产生单重态氧,高效光敏氧化一系列具有不同反应活性的底物,成为单重态氧化学中一个新的光敏氧化体系。  相似文献   
2.
本文通过扫描电镜分析,阐明了钨丝在烧氢定型过程中再结晶的规律;对白炽灯的寿命和光电参数作了测量,结果表明,不同的烧氢温度,钨丝的再结晶状况是不同的,白炽灯的寿命也不一样。实验指出,40瓦白炽灯用的WAL-1型钨丝,一次烧氢温度在1010±20℃为宜。  相似文献   
3.
A lamp‐based fluorescence detection (Flu) system for CE was extended with a wavelength‐resolved (WR) detector to allow recording of full protein emission spectra. WRFlu was achieved using a fluorescence cell that employs optical fibres to lead excitation light from a Xe‐Hg lamp to the capillary window and protein fluorescence emission to a spectrograph equipped with a CCD. A 280 nm band pass filter etc. together with a 300 nm short pass cut‐off filter was used for excitation. A capillary cartridge was modified to hold the detection cell in a commercial CE instrument enabling WRFlu in routine CE. The performance of the WRFlu detection was evaluated and optimised using lysozyme as model protein. Based on reference spectral data, a signal‐intensity adjustment was introduced to correct for transmission losses in the detector optics that occurred for lower protein emission wavelengths. CE‐WRFlu of lysozyme was performed using BGEs of 50 mM sodium phosphate (pH 6.5 or 3.0) and a charged‐polymer coated capillary. Using the 3‐D data set, signal averaging over time and emission‐wavelength intervals was carried out to improve the S/N of emission spectra and electropherograms. The detection limit for lysozyme was 21 nM, providing sufficient sensitivity to obtain spectral information on protein impurities.  相似文献   
4.
Chinese ink stick has a long history and a special importance in Chinese culture. Its main components are soot (normally pine wood soot and lamp soot) and animal glue; however, additives were added from time to time for different purposes. In order to see whether the two types of soot can be differentiated and the other constituents in Chinese ink sticks can be identified or not by Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC-MS) and GC-MS techniques, an initial study has been carried out. The main polycyclic aromatic hydrocarbons (PAHs) in soot could be identified, which are anthracene, fluoranthene, triphenylene and benz[e]acephenanthrylene. The main difference between those two types of soot is that the detectable amount of PAHs in lamp soot is much lower than in pine wood soot. In addition to this, the relative concentration of the main polycyclic aromatic hydrocarbons including anthracene, fluoranthene, pyrene, triphenylene and its isomer, benzo[k]fluoranthene and its isomers are different in the two types of soot. The relative content of benzo[k]fluoranthene is higher in pine soot than in lamp soot, which could be used to as a criterion to differentiate the two types of soot. Py-GC-MS technique is a very effective method to identify the main components of Chinese ink sticks, including the PAHs of soot, binding media and the additives of camphor and borneol in one analysis.  相似文献   
5.
通过测定不同覆盖度下的甲苯-正己烷、苯-正己烷、丙酮-正已烷和正戊烷-正己烷4个二组分气体在灯黑上的组成吸附等温线,发现它们有着共同的规律:随着覆盖度的增加,各体系的组成吸附等温线都向上靠近它们各自的气液平衡曲线。因此,基本上可以把二组分的气相与吸附相的平衡看成二组分的气液平衡,4个体系的组成吸附等温线基本上都可以通过理想溶液的相对挥发度方程式模拟得到。  相似文献   
6.
张少江 《光谱实验室》1999,16(2):205-207
介绍了721型分光光度计,灯电源电路和稳压电路故障现象,分析了故障产生的原因,提供了排除故障办法,对该仪器维修提供了借鉴的经验。  相似文献   
7.
基于计算流体动力学(CFD)方法,构建了包括固体散热结构和周围流体区域的全场三维数学模型。利用该模型进行了强制对流下大功率LED路灯散热性能的方向敏感性研究,并分析了翅片间距和入口风速对其方向敏感性的影响。研究结果表明:板翅式换热器具有明显的方向敏感性,随着翅片间距的增大和入口风速的减小,这种方向敏感性逐渐弱化。  相似文献   
8.
Thermal dependence on the small signal gain of Nd/Cr:YAG (yttrium aluminum garnet) ceramics was observed experimentally. Usually, Nd:YAG crystal and ceramics have remarkable gain reduction when optical pumping is performed and the temperature of the laser media is upped to 373 K. A CW laser light generated in a 1064 nm Nd:YAG laser oscillator was amplified by Nd/Cr:YAG ceramic amplifier, and the output power was measured at non-saturation level. Laser small signal gain of the ceramic disk was kept to 470 K. This property was remarkably different from one of Nd:YAG crystals or ceramics. The peak shift of the fluorescence was observed experimentally when the temperature is high.  相似文献   
9.
本文将纯稀土金属与碘化汞在加温下合成了钪、镝、铒和铥的碘化物。并用DTA方法测定了NaI-ScI_3,NaI-DyI_3,NaI-ErI_3和NaI-TmI_3二元体系的相图,它们都是简单的有低共熔点的二元体系,但是后面三个体系在固相有相变,可能是形成了不稳定的化合物。文中还制造了填充不同比例的碘化钠和稀土金属碘化物混合物的金属卤化物灯,将它们的发光特性与汞灯进行了比较。碘化钠和稀土金属碘化物的加入能明显地改善灯的色温,显色性和光效。  相似文献   
10.
长期以来,学界多将《歧路灯》视为世情小说、教育小说或家庭小说。然而其对程朱理学的推崇、明显的训诫教化特征和略显疏散的叙事风格,始终与上述定位不甚匹配,影响其在文学史上的价值认定和评价。鉴于明清时期家训撰写的普遍性,结合李绿园的社会身份及写作意图,依据《颜氏家训》等确立的家训文学类属标准,将《歧路灯》视为"家训小说",更利于其主题阐释和价值评估。  相似文献   
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