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501.
火焰原子吸收分析中表面活性剂对锰吸收讯号的增感效应及机理 总被引:3,自引:0,他引:3
提出了一种新的增感机理:在表面活性剂的cmc前,气溶腔形成过程中被测离子在小液滴上富集产生增惑;cmc后富集作用减小,但被测离子和表面活性剂形成胶团化物产生新的增感,火焰部分表面活性剂的不完全燃烧增强了火焰的还原性是增感因素之一。 相似文献
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以CK-4 15W40柴油机油为基础油,通过添加不同比例(质量分数分别为5%、10%、15%和20%)的0#柴油制备了不同燃油稀释比例的柴油机油,对稀释油品的基本理化性能(黏度、倾点、闪点和酸碱值)进行了测试. 采用曲轴箱模拟试验仪、加压差示扫描量热试验仪、点接触光弹流润滑试验台以及SRV试验机对稀释前后油样进行了结胶性能、抗氧化性能、弹流润滑以及边界润滑性能进行了研究. 结果表明:燃油稀释后的柴油机油黏度和闪点明显下降,倾点未发生明显变化,酸碱值和抗氧化性能有一定程度的降低. 弹流润滑条件下发动机油的油膜厚度降低,同时燃油稀释后柴油机油在边界润滑条件下的减摩与抗磨性能有所下降. 相似文献
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In this paper, by introducing the Lorentz-invariance-violation(LIV) class of dispersion relations(DR)suppressed by the second power(E/EQG)2, we investigated the effect of the LIV on the Hawking radiation of a charged Dirac particle based on tunneling from a Reissner-Nordstrom(RN) black hole. It was determined that the LIV speeds up black hole evaporation. As a result, the induced Hawking temperature was very sensitive to changes in the energy of the radiation particle. However, at the same energy level, it was insensitive to changes in the charge of the radiation particle. This is phenomenological evidence in support of the LIV-DR as a candidate for describing the effect of quantum gravity. Moreover, when the effect of the LIV was included, we discovered that the statistical correlations with the Planck-scale corrections between successive emissions could leak out information via radiation.We also determined that black hole radiation via tunneling is an entropy conservation process, and no information loss occurred during radiation, where the interpretation of the entropy of a black hole is addressed. Finally, we concluded that black hole evaporation is still a unitary process in the context of quantum gravity. 相似文献
506.
We report 20 Gb/s transmission of four-level pulse amplitude modulation(PAM) signal using a directly modulated tunable distributed Bragg reflector(DBR) laser. Transmission distance over 20 km was achieved without using optical amplifiers and optical dispersion compensation modules. A wavelength tuning range of 11.5 nm and a 3 dB bandwidth greater than 10 GHz over the entire wavelength tuning range were obtained. 相似文献
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Adaptive finite element method (AFEM) is broadly adopted to recover the internal source in biological tissues. In this letter, a novel dual-mesh alternation strategy (dual-mesh AFEM) is developed for biolumi- nescence tomography. By comprehensively considering the error estimation of the finite element method solution on each mesh, two different adaptive strategies based on the error indicator of the reconstructed source and the photon flux density are used alternately in the process. Combined with the constantly adjusted permissible region in the adaptive process, the new algorithm can achieve a more accurate source location compared with the AFEM in the previous experiments. 相似文献
509.
Effects of interface roughness on photoluminescence full width at half maximum in GaN/AIGaN quantum wells
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Low temperature photoluminescence (PL) measurements have been performed for a set of GaN/AlxGal xN quantum wells (QWs). The experimental results show that the optical full width at half maximum (FWHM) increases relatively rapidly with increasing A1 composition in the AlxGal xN barrier, and increases only slightly with increasing GaN well width. A model considering the interface roughness is used to interpret the experimental results. In the model, the FWHM's broadening caused by the interface roughness is calculated based on the triangle potential well approximation. We find that the calculated results accord with the experimental results well. 相似文献
510.