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1.
对TiO_2在氮气中的Mg热反应制备TiN粉末的方法进行了试验研究。结果表明,TiN的转化率受Mg粉加入量、反应物初始密度、MgO稀释剂和含氮化合物加入量的影响,且其影响作用依次递减;加入MgO可以明显改善TiN颗粒形态、粒径和分布,使其从多边形颗粒变为球形颗粒。通过工艺优化获得了球形窄筛分TiN微粉(0.2~1.0μm).  相似文献   

2.
TiN涂层可显著提高零件寿命.研究TiN涂层的滑动磨损行为有重要意义.研究结果表明,表面进行TiN涂层后,Cr12MoV和LM1两种材料的磨损抗力大幅度提高;与TiN涂层试样相配对的40Cr试样的失重明显高于与没有涂层试样相配对的40Cr试样的失重;Cr12MoV和LM1两种材料及其经过TiN涂层后的磨损抗力相差不大.讨论了TiN涂层对基体材料的要求.  相似文献   

3.
利用透射电镜研究了铁基体等离子体增强磁控溅射离子镀TiN膜的组织和结构。在沉积TiN之前先镀一层极薄的钛中间层,继之再沉积TiN。研究结果表明:在基体和中间层界面处有FeTi相;在中间层与后继膜的交接处α-Ti与Ti2N有结构匹配关系;靠近中间层的后继膜由Ti2N和TiN两相组成;而远离中间层的后继膜部分是TiN组成的。  相似文献   

4.
研究了不同的沉积电压对辅助加热式PCVD-TiN涂层的影响。实验证明,提高沉积电压可以细化TiN涂层的柱状晶结构,增加TiN涂层的显微硬度和沉积速率。在试验范围内,涂层内残存的氯含量基本不受沉积电压的影响。  相似文献   

5.
运用热力学对用TiCl3为钛源在低温下化学气相沉积TiN的可行性进行了论证,着重介绍了实验研究及实验结果。在所设计的TiCl3生成以及TiN形成的实验装置上,通过对HCl(g)与NH3的流量和沉积总压强的调节与控制,在较低的温度(550℃)下,在钢基材料上获得了TiN表面涂层。此研究旨在推动钢制工模具低温化学气相沉积TiN涂层的应用  相似文献   

6.
钛的氯化物化学气相沉积TiN热力学   总被引:1,自引:0,他引:1  
应用物质自由焓函数法(函数法)及化学反应平衡常数Kp,对TiCl2,TiCl3和TiCl4的生成反应以及它们与N2和H2反应化学气相沉积TiN的热力学进行了计算与分析。结果表明,用TiCl3与N2和H2的气相反应,能在较低温度下获得TiN,为低温化学气相沉积TiN提供了理论依据  相似文献   

7.
针对高速钢刀具热阴极等离子镀TiN涂层工艺参数进行试验研究,并对涂层刀具的 性能进行了分析。  相似文献   

8.
等离子化学气相沉积硬膜技术研究   总被引:1,自引:2,他引:1  
用等离子体化学气相沉积(PCVD)技术制备了TiN、TiC、Ti(CN)和(TiSi)N膜及其组合的多层膜。PCVD具有很好的覆盖性,PCVD-TiN具有很好的耐磨、蚀性,膜与基体结合良好,因而用PCVD法在高速钢刀具、模具及轴承上沉积TiN可大大提高其使用寿命。PCVD-TiN和Ti(CN)膜无明显柱状晶,其显微硬度高于TiN亦可用于高速钢刀具、模具上提高其使用寿命。PCVD-(TiSi)N,晶  相似文献   

9.
TiN超微颗粒的合成研究   总被引:1,自引:0,他引:1  
采用直流电弧等离子体法,在氮气气氛下用块状海绵钛成功地合成了TiN超微颗粒。X射线衍射和透射电镜天空表明,通过改变实验条件,可以获得单一物相构成的TiN超微颗粒,其晶格常数不随氮气压力变化而改变。TiN粒径分布随氮气压力增加而变大,其超微颗粒的外形在气压低时主要呈立方体或长方体结晶形态。  相似文献   

10.
在SPF-430H射频磁控射系统上用反应溅射方法制备TiN薄膜,研究了制备工艺,讨论了薄膜的光学性能与溅射工艺参数的关系,实验结果在优化制备工艺基础上能制备出具有优良光学性能(高折射率、高透射率)的TiN薄膜。  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.
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   

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 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   

15.
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   

16.
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   

17.
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   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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