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51.
上三叠统须家河组五段是四川盆地川西坳陷新场气田陆相天然气勘探的重点层系之一,但对须五段烃源岩品质的研究程度较低且认识存在分歧。对新场须五段泥岩发育特征和有机地球化学特征研究表明,新场须五段泥岩平均厚度为285.3m,各亚段均表现出北薄南厚的特征。须五段泥岩样品TOC含量、生烃潜力(S1+S2)和氯仿沥青“A”含量平均分别为2.17%、2.26mg/g和0.264‰,有机质丰度整体达到了中等烃源岩的标准;干酪根类型指数(TI)均小于0,δ13C平均值为-25.0‰,有机质类型主要为腐殖型和腐泥_腐殖型;镜质体反射率(RO)平均值为1.17%,主体处于生油高峰期后。新场须五段泥岩生气强度主体介于(3~16)×108m3/km2之间,具备形成中小型气田的资源基础。新场须五段泥岩总生气量相对较低,生成的天然气无法完全驱替掉地层中的水,因此气藏中天然气充满度整体偏低,导致在试采过程中气水同产且天然气产量整体较低。  相似文献   
52.
光伏MPPT系统电压控制器的优化设计   总被引:2,自引:0,他引:2       下载免费PDF全文
分析了光伏MPPT系统构成及工作原理。使用基于变步长电压扰动法作为功率/电压寻优控制器。为实现快速稳定的光伏MPPT响应,重点对光伏输出电压控制器的电压环进行优化设计。设计了一种光伏MPPT电压复合控制器,采用电压顺馈+PI调节器的方法实现。通过对光伏输出电压控制器进行数学建模得到电压闭环传递函数。确定了最佳PI调节器参数以得到快速稳定的MPPT控制。仿真分析结果以及试验结果表明,此电压复合控制器能够快速、稳定地实现光伏MPPT响应。  相似文献   
53.
Organic multiple quantum well(OMQW)structures consisting of alternating layers of tris(8-quinolinolato)aluminum(Ⅲ)(Alq3)an 2-(4-biphenylyl)-5-(4-ter-butylphenyl)-(1,3,3-oxadiazole)(PBD)have been fabricated by organic molecular beam deposition(OMBD).The individual layer thickness in the multilayer samples was varied from 6 nm tp 20nm.The multiple quantum well structures were determined by low angle X-ray diffraction,optical absorption and photoluminescence(PL).The PL spectra narrow and the emission energy has been observed to shift to higher energy compared with that in the monolayer structure,suggesting a quantum size effect.  相似文献   
54.
HoleMobilityinPoly(N-vinylcarbazole)ThinFilmBasedonSilicium①②CHENBaijun,WANGXiaowei③,LIUShiyong(StateKeyLab.onIntegratedOptoe...  相似文献   
55.
有机过氧化物是烯烃聚合工业中重要的引发剂。针对烯烃聚合工业用有机过氧化物自分解温度低、易发生反应失控引发火灾爆炸等情况,简要叙述了有机过氧化物的结构、分类、化学性质以及反应特性,重点对其储存、使用、管理等过程中的危险性进行了分析。提出过氧化物储存、运输、使用、报废等方面的风险消减与事故预防措施。  相似文献   
56.
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since June 2006 are reviewed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
57.
We report on the fabrication of organic photodetectors (OPD) based on isolated islands of P3HT:PCBM. Pattern transfer to the active material was done with photolithography based on non-fluorinated solvents and the excessive organic semiconductor was removed with oxygen plasma reactive ion etching. The photoresist system used was found to be benign to the P3HT:PCBM layer as confirmed by absorption, thickness and roughness measurements. Current–voltage characteristics and external quantum efficiency (EQE) remained unchanged after the patterning process. It was demonstrated that it is possible to photolithographically pattern isolated islands with 200 μm edge length with the same dark current density (<10−5 A/cm2 at −2 V bias voltage) and photocurrent density (>5 × 10−3 A/cm2 at −2 V). Furthermore, concerning the solar cell performance, the patterned, small-area devices showed power conversion efficiency of 2.1% and fill-factor of 60%. Dark current was observed to depend on the size of the remaining semiconductor island, which was demonstrated on OPDs with diameter of 50 μm. The presented results show the feasibility of fabrication of isolated devices based on organic semiconductors patterned with non-fluorinated photolithography.  相似文献   
58.
We have demonstrated fast operation of printed organic inverter circuits. We employ a soluble organic semiconducting material which has high field-effect mobility and ink-jet printed source/drain electrodes with short channel length. Appropriate concentration of the semiconducting solution and modification layer of source/drain electrodes improve both mobility and on/off ratio. The fabricated transistors with a short channel length (4 μm) exhibit excellent mobility (1.2 cm2/V s), high on/off ratio (>105) and operational stability. The diode-load inverter with a narrow channel and low parasitic capacitance operate at 8 kHz at 20 V. These results will lead to significant progress in applications of printed organic circuits.  相似文献   
59.
We investigated the optical properties and the degradation process of the organic p-type semiconductor poly(triarylamine) (PTAA) in the mid infrared region. The dielectric function of PTAA was determined in the spectral region of 700 up to 6000 cm−1 by modeling ellipsometric measurements. Due to degradation at 65 °C, PTAA thin films developed carbonyl and hydroxyl features in the infrared spectra. Degradation under 85% RH additionally led to absorption signals of water. A degradation of the bare gold substrates was also observed. For bare gold films, morphology changed upon degradation and adsorption of hydrocarbons from the ambience took place.  相似文献   
60.
Diketopyrrolopyrroles (DPPs) have recently gained attention as building-blocks for organic semiconducting polymers and small molecules, however the semiconducting properties of their hydrogen-bonded (H-bonded) pigment forms have not been explored. Herein we report on the performance of three archetypical H-bonded DPP pigments, which show ambipolar carrier mobilities in the range 0.01–0.06 cm2/V s in organic field-effect transistors. Their semiconducting properties are correlated with crystal structure, where an H-bonded crystal lattice supports close and relatively cofacial π–π stacking. To better understand transport in these systems, density functional theory calculations were carried out, indicating theoretical maximum ambipolar mobility values of ∼0.3 cm2/V s. Based on these experimental and theoretical results, H-bonded DPPs represent a viable alternative to more established DPP-containing polymers and small molecules where H-bonding is blocked by N-alkylation.  相似文献   
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