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101.
根据测试数据,分析模拟了铜铟镓硒(CIGS)薄膜光伏组件中电池的活性区域、非活性区域与封装材料之间界面的光学特性对组件的短路电流产生的影响。根据组件结构建立了光学模型,从光学模拟结果分析组件内的反射与吸收。发现电池前电极透明导电氧化物薄膜(TCO)与封装材料界面的反射不可忽视,提出通过在透明导电氧化物薄膜与封装材料之间添加减反射层,并以MgO作为膜层材料以降低活性区域的界面反射;模拟了在非活性区域一次反射光角度与二次反射的关系,由此分析了非活性区域反射面倾角、镜面反射与漫反射比例对光利用的影响。模拟结果显示,活性区域的减反层结构可降低透明导电氧化物薄膜表面的反射率1%以上,而通过在非活性面积区域制备光反射结构,理论上能够利用非活性区域光照超过50%。 相似文献
102.
103.
T. Pietraβ R. Seydoux R.E. Roth H. Eckert A. Pines 《Solid state nuclear magnetic resonance》1997,8(4):265-267
Cross polarization from 31P to 77Se is demonstrated in β-P4Se3. This material, an inorganic glass, is readily synthesized from the elements and serves as a convenient sample for setting the Hartmann-Hahn condition. 相似文献
104.
Optical properties are studied for Se species accommodated in channels of an AlPO4–5 single crystal. Polarized Raman spectra show that the Se species is of helical chain structure with D3symmetry. The optical phonon modes of the Se chains are shifted towards higher frequencies from that of the trigonal Se crystal, because of the loss of inter-chain interactions in Se/AlPO4–5. High anisotropic absorption spectra have been observed for the Se chains. The lowest excitation energies are shifted towards high energy about 0.6 eV from the band edge transitions of the trigonal Se crystal. The blue shift is attributed to the quantum confinement of carriers in a Se chain with diameter 7.3 Å. 相似文献
105.
选取包头市区正常产妇68名及其所生新生儿作为研究对象。分娩后抽取产妇肘静脉血及新生儿脐动脉血,分析其血清中铁、锌、铜、硒的含量.研究结果揭示:新生儿脐带血清中铁、铜、硒的含量均高于产妇血清中的含量,铁与铜有显著性差异(P<0.05),硒的差异不显著(P>0.05);而锌则相反,新生儿脐带血清中的含量低于产妇血清中的含量,二者有高度显著性差异(P<0.01)。产妇血清中Fe/Zn、Cu/Zn、Se/Zn比值分别为3.83、2.78、0.08;而新生儿脐带血清中Fe/Zn、Cu/Zn、Se/Zn比值则各为9.56、6.80、0.19,进一步说明新生儿脐带血清中的锌含量降低,其它元素含量增加。 相似文献
106.
本文用MOCVD技术在GaAs衬底上成功地制备了具有波导结构的Zn0.8Cd0.2Se-ZnSe应变层超晶格样品,在77K温度的光致发光光谱中观测到n=1的重空穴和轻空穴激子的辐射复合。在光泵浦下,在波导结构的F-P腔中观测到具有多模结构的受激发射,受激发射谱中的不同模具有不同的阈值功率密度;时间延迟衰减曲线的半宽度越窄,阈值光强越大. 相似文献
107.
A flow-injection analysis atomic absorption spectrometric (FIA-AAS) method was developed for the determination of trace amounts of arsenic, selenium and mercury in a proposed estuarine sediment standard reference material (SRM 1646a). The samples were prepared in two manners: a) A wet digestion procedure with HNO3, H2SO4, and HClO4 using a reflux column and b) A microwave-oven digestion procedure utilizing HNO3, H2SO4, and HCl for As and Se, and HNO3 for Hg. Microwave-oven digestion provides results comparable to those found by reflux column digestion and reduces the sample preparation time by a factor of 10. The proposed method employing the microwave-oven digestion procedure coupled with FIA-AAS for As and Se, and FIA-CVAAS for Hg, has detection limits of 0.15 ng As/ml, O.17 ng Se/ml and 0.15 ng Hg/ml.On leave from the Defense Metallurgical Research Laboratory, Hyderabad, India 相似文献
108.
109.
Zsolt?Ajtony Norbert?Szoboszlai Zsuzsanna?Bella Szilvia?Bolla Pál?Szakál László?BencsEmail author 《Mikrochimica acta》2005,150(1):1-8
A flow injection hydride generation graphite furnace atomic absorption spectrometric (FI-HG-GFAAS) method was applied to the determination of Se in Se-doped and undoped cereals and bakery products. For the purpose of doping, the soils used for the cultivation of the cereals were dosed with Se-doped foliar fertilizers. The samples were dissolved in a mixture of HNO3 and H2O2 solutions using microwave-assisted digestion. The decomposition of H2Se generated from the sample solutions and the trapping of elemental Se were performed at a temperature of 300°C on an Ir-pretreated integrated graphite platform of a transversally heated graphite atomizer (THGA). For release of the trapped Se within a fairly short atomization time (5s), an atomization temperature of 2200°C was observed to be optimal. The overall efficiency of hydride generation, transport and trapping was 86%.The upper limit of the linear dynamic range of calibration was 10µgL–1, which corresponds to 0.5µgg–1 for solid samples. Recovery of the samples spiked with SeVI solutions was found to be 93±6% on average. The relative standard deviation of the determinations was less than 8%. The limit of detection was found to be 0.06µgL–1, corresponding to 3ngg–1 for solid samples. The accuracy of the method was verified with the use of IAEA-155 (whey powder) certified reference material. End-capped THGA tubes resulted in an extension of the linear calibration range compared to that of standard THGAs.The Se content in bakery products made of undoped cereals ranged from 7.7 to 68ngg–1 (wet weight) in 18 samples, whereas the Se content of the corresponding cereals was found to be below 100ngg–1 (wet weight). The Se level of cereals grown on soils treated with Se-doped fertilizers ranged from 128 to 1046ngg–1 (wet weight), and it depended linearly on the Se concentration of the corresponding foliar fertilizer. 相似文献
110.
铬,硒,镉,锰与心脑血管疾病 总被引:1,自引:0,他引:1
通过对50例心脑血管疾病病人及50例健康对照组血中微量元素铬、硒、镉、锰的检测分析证实,心脑血管疾病病人血清Cr、Se含量下降,Cd含量未见明显升高,并进一步探讨了这些微量元素与心脑血管疾病的发生发展的关系及其临床意义。 相似文献