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81.
In this study, back‐contacted back‐junction n‐type silicon solar cells featuring a large emitter coverage (point‐like base contacts), a small emitter coverage (point‐like base and emitter contacts), and interdigitated metal fingers have been fabricated and analyzed. For both solar cell designs, a significant reduction of electrical shading losses caused by an increased recombination in the non‐collecting base area on the rear side was obtained. Because the solar cell designs are characterized by an overlap of the B‐doped emitter and the P‐doped base with metal fingers of the other polarity, insulating thin films with excellent electrical insulation properties are required to prevent shunting in these overlapping regions. Thus, with insulating thin films, the geometry of the minority charge carrier collecting emitter diffusion and the geometry of the interdigitated metal fingers can be decoupled. In this regard, plasma‐enhanced chemical vapor deposited SiO2 insulating thin films with various thicknesses and deposited at different temperatures have been investigated in more detail by metal‐insulator‐semiconductor structures. Furthermore, the influence of different metal layers on the insulation properties of the films has been analyzed. It has been found that by applying a SiO2 insulating thin film with a thickness of more than 1000 nm and deposited at 350 °C to solar cells fabricated on 1 Ω cm and 10 Ω cm n‐type float‐zone grown silicon substrates, electrical shading losses could be reduced considerably, resulting in excellent short‐circuit current densities of more than 41 mA/cm2 and conversion efficiencies of up to 23.0%. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
82.
通过实施防止设备早期故障的方案来延长老连铸设备的使用寿命并提高产量.奥钢联工业服务公司巴西分公司执行的一项提高连铸机性能的维护合同,使用户的设备使用寿命得到显著改善,而其除了支付按吨钢产量固定费率计算的维修费用外,无需支出其他任何费用.  相似文献   
83.
The retrospective results of carbon prostheses for knee ligament reconstruction in 120 patients, as established by questionnaire, are reported at 10 +/- 2 years follow-up. Eighty patients could also be reviewed clinically. Some 60% of the patients showed good subjective function at reduced activity level. Complications were seen in 72.5% of the patients with rupture of the carbon prosthesis and in 68% of those with synovitis. X-ray showed osteoarthritis in up to 59% of the patients. Carbon prostheses for collateral ligament reconstruction (85% medial, 5.8% lateral) were successful in 75% of cases. Activity and time seem to be less responsible for failure of the carbon prostheses than the features of growing in. Destruction of the knee joint over time is due to reactive synovitis and catabolic enzyme reaction and correlates with joint effusion and pain. If these problems appear, (arthroscopic) resection of the synovia is indicated to interrupt the circulus vitiosus.  相似文献   
84.
Lead optimization of a high‐throughput screening hit led to the rapid identification of aminopyrimidine ZK 304709, a multitargeted CDK and VEGF‐R inhibitor that displayed a promising preclinical profile. Nevertheless, ZK 304709 failed in phase I studies due to dose‐limited absorption and high inter‐patient variability, which was attributed to limited aqueous solubility and off‐target activity against carbonic anhydrases. Further lead optimization efforts to address the off‐target activity profile finally resulted in the introduction of a sulfoximine group, which is still a rather unusual approach in medicinal chemistry. However, the sulfoximine series of compounds quickly revealed very interesting properties, culminating in the identification of the nanomolar pan‐CDK inhibitor BAY 1000394, which is currently being investigated in phase I clinical trials.  相似文献   
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