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1.
用光电容方法研究了GaP(N)样品中深能级杂质缺陷;以曲线拟合方法计算机分析多能级响应的瞬态光电容谱,确定深能级参数:能级位置、能级浓度和光发射率等;并测量了GaP(N)LED的发射光谱和发光效率。结果表明:发光效率较低的LED(η_(ext)=0.019%)中存在着E_1、E_2、E_3、E_4、E_5、H_1多种深能级;发光效率较高的LED(η_(ext)=0.096%),深能级较少(E_3、E_4、H_1)。这些深能级具有无辐射复合中心作用,使发光效率明显降低。  相似文献   

2.
本文研究了粉末光导材料的吸收光谱,77K温度下的光致发光谱和深能级发射光谱以及光电导的光谱响应特性。从吸收光谱和深能级发光光谱中判明了施主能级、Cu~+能级以及S和Cd的空位能级的位置。  相似文献   

3.
对GaAsP、GaAIAs发光二极管中的深能级,用瞬态电容谱(DLTS)方法研究得知,二极管在退化前后存在着几个深能级,并测得其能级深度、浓度和俘获截面等主要参数。讨论了这些深能级的物理成因及其对发光效率与退化特性的作用。  相似文献   

4.
本文先从定态薛定谔方程求解出一维无限深方势阱的能级公式,再从一维半无限高方势阱的能级图解图导出一维无限深方势阱的能级公式,说明一维无限深方势阱的能级确实是一维半无限高方势阱的能级在特定条件下的极限,最还对一维半无限高方势阱的能级数目进行了讨论,给出了相应的判别公式。  相似文献   

5.
本文应用深能级瞬态谱(DLTS)和光深能级瞬态谱(ODLTS)技术研究了掺Ga的ZnSe晶体中的深能级.发现ZnSe:Ga晶体中有一个与Ga有关的施主能级位于导带底下0.17eV处,两个与Ga有关的受主能级分别位于价带顶上0.65eV和0.72eV处.文中还对这些能级的起源进行了讨论.  相似文献   

6.
半导体中深能级杂质对半导体材料的物理性质和半导体器件的性能有重要影响。本文概述了近年来应用势垒电容研究半导体中深能级杂质的一些主要方法,特别是利用含有深能级杂质的p—n结(或Schottky 结)电容与时间有关的瞬态电容法,并且讨论了解释这些测量结果的理论模型。研究深能级杂质的 DLTS 法能比较迅速、精确地测定深能级杂质的多种参数,在此基础上进一步改进,从而提高测量精度。  相似文献   

7.
介绍一种计算有限深球形势阱束缚态能级的近似计算方法,并对具体问题进行了这么些人出了有限深球形势阱的能级和波函数与无限深球形势阱的能级和波函数之间的关系。  相似文献   

8.
用 AsCl_3/Ga/H_2气相外延系统在 GaAs 衬底上生长出GaAs 外延层并制成 Au-GaAs 肖特基结构.利用高分辨率深能级瞬态谱(HDDLTS)仪研究了外延层中深能级的特性.结果表明,缺陷和杂质在外延层中引进若干较高浓度的深能级,经退火后缺陷深能级会被消除.  相似文献   

9.
应用深能级瞬态谱(DLTS)技术,研究了GaAs0.55P0.45红色发光二极管深能级.结果表明,有B陷阱的GaAS0.55P0.45红色发光二极管亮度比有C陷阱的低;并对B陷阱深能级位置的真实值进行了详细计算.  相似文献   

10.
深能级中心能显著影响太阳电池性能.制作了以掺杂石墨为背接触层的CdS/CdTe薄膜太阳电池,用深能级瞬态谱研究了它们的深能级中心.共发现了6个深中心,确定了其中两个深中心的能级位置,分别是位于EC-0.223 eV的 E3和位于EV+0.077 eV的H3.它们主要来源于Cd与Te的空位和间隙离子、O和Cl离子以及它们相互作用形成的复合体等.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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