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1.
利用双离子束溅射沉积共溅射方法制备了富Si-SiO2薄膜,研究了沉积参数、时间、工作气压PAr.基片温度等对沉积速率的影响,用TEM和XRD分析了样品的结构,当基片温度Ts<450℃时,所制备一系列样品均为非晶结构,当沉积基片温度较高时(Ts≥450℃),薄膜样品中才出现Si的颗粒.我们还分析了样品的室温光致发光现象,从PL谱中可以看出,样品有~320nm、~410nm、~500nm和~630nm四个PL峰,并对其发光机理进行初步探讨.  相似文献   

2.
采用射频磁控溅射复合靶技术制备了Si-SiO2薄膜,并在各种温度下进行了退火处理.XRD分析表明Si-SiO2薄膜为非晶结构,XPS分析表明样品主要是以SiO1.90的形式存在,它是富硅或缺氧的结构.在室温下观察到了可见光致发光(PL)现象,探测到样品的峰位分别在370m、410m、470m和510nm.结合激发谱对相应的激发与发光中心进行了讨论.另外,还研究了退火温度对其峰位与峰强的影响.  相似文献   

3.
利用双离子束溅射沉积共溅射方法制备了富Si SiO2 薄膜 ,研究了沉积参数、时间、工作气压PAr、基片温度等对沉积速率的影响 ,用TEM和XRD分析了样品的结构 ,当基片温度Ts <4 50℃时 ,所制备一系列样品均为非晶结构 ,当沉积基片温度较高时 (Ts ≥4 50℃ ) ,薄膜样品中才出现Si的颗粒 我们还分析了样品的室温光致发光现象 ,从PL谱中可以看出 ,样品有~ 32 0nm、~ 4 10nm、~ 560nm和~ 630nm四个PL峰 ,并对其发光机理进行初步探讨  相似文献   

4.
采用射频磁控溅射复合靶技术制备了Si SiO2薄膜,并在各种温度下进行了退火处理.XRD分析表明Si SiO2薄膜为非晶结构,XPS分析表明样品主要是以SiO1.90的形式存在,它是富硅或者缺氧的结构.在室温下观察到了可见光致发光(PL)现象,探测到样品的峰位分别在370nm、410nm、470nm和510nm.结合激发谱对相应的激发与发光中心进行了讨论.另外,还研究了退火温度对其峰位与峰强的影响.  相似文献   

5.
InSb薄膜广泛应用于高精度的光电存储、红外探测和红外热成像技术以及超分辨掩膜层技术中.热导率及其温度特性是影响薄膜实际应用的关键因素.采用瞬态热反射方法测试了厚度为70~200nm的InSb薄膜在非晶态和晶态下热导率,并探讨了其中的传热机理.对于晶态InSb薄膜,热导率为(0.55±0.055)W/(m·K),并且随温度的变化不明显;而非晶态InSb薄膜在温度450K以下时热导率为(0.37±0.037)W/(m·K).当温度在450K以上时,由于薄膜从非晶态转化为晶态,其热导率经历了一个突然的升高过程.无论是晶态还是非晶态薄膜样品,热导率与薄膜厚度都没有明显依赖关系.研究结果可以为InSb薄膜的实际应用提供有益的参考.  相似文献   

6.
采用FTIR,XRD,XPS和TG-DTA等表征了一组具有不同组成的由沉淀-混合沉淀法制得的SO2-4/ZrO2-SiO2超强酸催化剂.由实验结果可知,催化剂的超强酸点可能是由于SO2-4基团与二元氧化物中的锆相互作用而产生的.与SO2-4/ZrO2催化剂不同的是,即使在650 ℃以上温度下焙烧的SO2-4/ZrO2-SiO2催化剂也是无定型的.800 ℃以上焙烧前体二元氧化物时,按照锆硅比的不同将出现两种不同的情况,硅锆比小于8时,其XRD谱图上出现属于四方晶型的二氧化锆的衍射峰;而当硅锆比大于8时,XRD谱图显示产生了一种新型的结晶体.研究结果表明,SO2-4基团与二元氧化物中Zr原子作用形成了酸性中心.  相似文献   

7.
采用FTIR ,XRD ,XPS和TG_DTA等表征了一组具有不同组成的由沉淀 -混合沉淀法制得的SO2 - 4/ZrO2 _SiO2 超强酸催化剂 .由实验结果可知 ,催化剂的超强酸点可能是由于SO2 - 4基团与二元氧化物中的锆相互作用而产生的 .与SO2 - 4/ZrO2 催化剂不同的是 ,即使在 6 5 0℃以上温度下焙烧的SO2 - 4/ZrO2 _SiO2 催化剂也是无定型的 .80 0℃以上焙烧前体二元氧化物时 ,按照锆硅比的不同将出现两种不同的情况 ,硅锆比小于 8时 ,其XRD谱图上出现属于四方晶型的二氧化锆的衍射峰 ;而当硅锆比大于 8时 ,XRD谱图显示产生了一种新型的结晶体 .研究结果表明 ,SO2 - 4基团与二元氧化物中Zr原子作用形成了酸性中心 .  相似文献   

8.
采用RF磁控溅射技术制备含纳米硅的SiO2薄膜.通过对Si-SiO2复合靶的比分进行调节控制,并在不同的温度下进行高温退火得到不同粒径的纳米硅.利用XRD对样品进行分析得出纳米硅的平均粒径;对样品测量光致发光谱,其发光峰分别位于361 nm和430 nm,比较发现光致发光的峰位随比分的改变有微小的蓝移.文中对发光机理进行初步讨论.  相似文献   

9.
采用FTIR,XRD,XPS和TG-DTA等表征了一组具有不同组成的由沉淀-混合沉淀法制得的SO^2-4/ZrO2-SiO2超强酸催化剂,由实验结果可知,催化剂的超强酸点可能是由于SO^2-4基因与二元氧化物中的锆相互作用而产生的,与SO^2-4/ZrO2催化剂不同的是,即使在650℃以上温度下焙烧的SO^2-4/ZrO2-SiO2催化剂也是无定型的.800℃以上焙烧前体二元氧化物时,按照锆硅比的不同将出现两种不同的情况,硅锆比小于8时,其XRD谱图上出现属于四方晶型的二氧化锆的衍射峰;而当硅锆比大于8时,XRD谱图显示产生了一种新型的结晶体,研究结果表明,SO^2-4基因与二元氧化物中Zr原子作用形成了酸性中心。  相似文献   

10.
采用离子注入法及退火工艺,在硅基二氧化硅薄膜中制备了镶嵌结构的天然Ge纳米晶样品. 通过退火实验研究,发现随着退火温度的升高,纳米晶的晶态峰峰位红移,这意味着Ge纳米晶受到的应力减小. 当退火温度达到 700 ℃时,纳米晶的晶态峰强度显著增强,而且薄膜中与Ge有关的缺陷发光减弱. 采用中子嬗变掺杂法对天然Ge纳米晶进行了掺杂,X射线荧光光谱数据表明,样品中成功的引入了Ga杂质和As杂质. 薄膜中形成的与Ge有关的缺陷具有稳定的结构,中子辐照之后其发光仍然存在,而且,掺杂后的样品中没有发现与Ga或As有关的  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
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   

16.
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   

17.
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   

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.
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   

20.
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   

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