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51.
Photodetectors have a growing number of diverse applications in both military and civilian use, and improving their response bandwidth is of great importance. Broad spectral response photosensitive organic field-effect transistors (PhOFETs) are realized by adopting hybrid planar-bulk heterojunction (HPBHJ) as the active structure that containing three molecules with complementary optical absorption. PhOFETs based on the HPBHJ composed of 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA), chloroaluminum phthalocyanine (AlClPc) and C60, and SiO2 as the gate dielectric exhibit photo response in the broadband wavelength range of 300–850 nm. At an incident optical intensity of 0.07 mW/cm2, the mean photoresponsivity and uniformity factor were 0.40 A/W and 0.79, respectively. Furthermore, by replacing SiO2 gate dielectric with polyvinyl alcohol (PVA), the device performance could be further improved, the mean photoresponsivity was increased to 2.44 A/W. The physical origin of the performance improvement is discussed. 相似文献
52.
汶川地震灾区部分城镇的房屋震害分析 总被引:1,自引:0,他引:1
“5·12”汶川地震山移河堵,四川省震害灾区的人民经受了极大的灾害摧残,笔者就都江堰市、彭州市区及有关城镇主要房屋建筑类型的震害现象,进行粗略分类,并进行初浅的原因分析。天灾难御,但我们可从生死灾难中振醒,从技术、材料、工艺、管理等方面反思而应有所提高。 相似文献
53.
Assessment of quality changes in frozen sardine (Sardina pilchardus) by fluorescence detection 总被引:4,自引:4,他引:0
Santiago P. Aubourg Carmen G. Sotelo Ricardo Pérez-Martín 《Journal of the American Oil Chemists' Society》1998,75(5):575-580
The formation of fluorescent compounds was tested as a quality assessment during the frozen storage of sardine at −18°C (up
to 24 mon) and at −10°C (up to 120 d). The fluorescence ratio between two excitation/emission maxima (393/463 and 327/415
nm) was studied in the aqueous (δF
aq) and organic (δF
or) extracts after Bligh and Dyer extraction of the white muscle. Fluorescence results were compared to common quality indices
[total volatile base-nitrogen (TVB-N); conjugated dienes; thiobarbituric acid index (TBA-i); and free fatty acids (FFA)].
δF
aq showed good correlations with storage time (r=0.80 and r=0.72 at −18 and −10°C, respectively) and TBA-i (r=0.92 and r=0.81). Principal-component analysis grouped δF
aq with quality indices that are sensitive for the assessment of fish damage during frozen storage at both temperatures (TBA-i
and FFA at −18°C; BVT-N, TBA-i, and FFA at −10°C). According to these results, fluorescence detection of interaction compounds
in the aqueous phase can provide an accurate method to assess quality differences during frozen storage of fish. 相似文献
54.
55.
聚焦食品市场,从职业打假案件的诉讼现状入手,总结分析了目前理论与实务中关于职业打假行为存在的问题与争议,讨论了职业打假人知假买假的权利保护限制必要性,并尝试从多个层面对其职业打假行为进行引导规制,如明确职业打假人的法律地位、引导打假行为正当化规范化等。 相似文献
56.
汶川地震拱桥震害明显,且震害随桥梁规模、连孔情况的不同而发生变化,故对两种类型进行统计归纳,得到相关统计规律. 相似文献
57.
58.
张玮 《可编程控制器与工厂自动化(PLC FA)》2009,(12):99-100,113
本文主要讨论了如何利用光敏元件对光强度进行检测,并参照强度检测的结果对光的强度进行分类,最终利用PWM波实现对液晶屏背光灯进行人性化控制。 相似文献
59.
60.
The purpose of this study is to show the capability of recurrent neural nets (RNN) for condition monitoring and diagnosis in nuclear power plant systems and rotating machinery. In the first application, the study addresses the use of RNN for detecting anomalies introduced from the simulated power operation of a high-temperature gas cooled nuclear reactor. In the second, it is used to detect the motor bearing damage using a coherence function approach, which is defined between the motor current and vibration signals, for induction motors. Hence, the high performance of Elman's RNN was shown by means of two different applications. 相似文献