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1.
采用反应磁控溅射方法,在不同沉积温度条件下制备了一系列多晶TiN/SiNx纳米多层膜,并用X射线衍射仪(XRD)、X射线反射仪(XRR)及纳米压痕仪(Nanoindenter)表征了材料的微观结构及力学性能。结果表明,沉积温度对多层膜的界面结构、择优取向及力学性能有显著影响:当沉积温度为室温时,多层膜的界面较高温条件下粗糙;而多层膜的择优取向在沉积温度为400℃时呈现强烈的TiN(200)织构;多层膜的硬度及弹性模量在室温至400℃温度范围内变化不大。  相似文献   

2.
牡丹切花贮藏期内源激素水平变化规律的研究   总被引:10,自引:0,他引:10  
杨秋生  宋鸿雁 《河南科学》1997,15(3):303-306
对不同温度下贮藏的牡丹切花内源激素水平的测定结果表明:低温(4℃)贮藏,内源乙烯和吲哚乙酸水平显著低于室温(18℃)贮藏,细胞分裂素水平高于室温贮藏,低贮藏切花寿命较室温贮藏可延长10天左右。  相似文献   

3.
明胶的干燥温度,粘度和分子量分布   总被引:2,自引:0,他引:2  
通过实验探讨明胶干燥温度对明胶粘度的影响,并从分子量分布和数均分子量变化的角度阐明这种影响的内在原因.实验结果表明:经室温干燥的活性胶、惰胶、复合胶和食用胶再经105℃干燥与只经室温干燥相比,其粘度上升;经室温干燥的PA胶再经105℃干燥与只经室温干燥相比,粘度下降.明胶经室温干燥后再经105℃干燥,随着干保温度的提高,明胶的分子量分布和数均分子量发生变化,导致宏观上明胶粘度的变化.活性胶、惰胶、复合胶和食用胶经105℃干燥后分子量分布向分子量大的方向变化,数均分子量变大;而PA胶经105℃干燥后,分子量分布向分子量小的方向变化,数均分子量变小.  相似文献   

4.
应用DTA/T/EGD/GC在线联用技术,对倍半氧化羧乙基锗(Ge-132)在N2气氛中的热分解反应历程(室温~980℃)进行了研究。依据DTA/T/EGD/GC提供的信息,分别对220℃、350℃、650℃、800℃、900℃、980℃等反应温度下的热分解残物,应用XRD仪进行了物相鉴定,并测定了Ge-132在N2气氛中(室温~930℃)的TG/DTG曲线。对DTA曲线上显示的五个吸热效应和一个放热效应的性质作出了判断和验证,并对该热分解反应中逸出气的组成演变、残物中的Ge和GeO2晶相的析出以及GeO2在高温下转化为Ge的反应历程进行了探讨。  相似文献   

5.
采用直流反应磁控溅射方法在304不锈钢表面沉积TiN薄膜.利用场发射扫描电镜、X射线衍射仪和纳米压痕仪研究基体温度对TiN薄膜结构与性能的影响.结果表明:TiN薄膜为柱状结构,表面平整、致密.薄膜为面心立方结构(fcc)TiN并存在择优取向,室温和150℃时薄膜为(111)晶面择优取向,300和450℃时薄膜为(200)晶面择优取向;室温时薄膜厚度仅为0.63μm,加温到150℃后膜厚增加到1μm左右,但继续加温对膜厚影响不明显;平均晶粒尺寸随着基体温度的升高略有上升;薄膜的硬度、弹性模量和韧性(H3/E*2)随基体温度的升高而增加,最值分别达到25.4,289.4和0.1744GPa.  相似文献   

6.
采用中频磁控溅射技术在钼圆片表面镀覆钌薄膜,通过X射线衍射仪、扫描电镜、平整度仪、宏观浸蚀试验和百格测试等对镀层进行表征和检测,研究不同沉积温度对薄膜微观结构和附着力的影响。结果表明,随着沉积温度由室温升至200℃,钌薄膜的表面平整性和致密性逐步改善,附着力得以提高;200℃沉积薄膜的膜/基结合力最大,其微观结构、致密性等也均达到最优;但当沉积温度进一步提高到300℃时,钌薄膜的表面起伏反而增大,附着力有所下降。  相似文献   

7.
通过光学显微镜、透射电子显微镜、X射线衍射仪以及显微硬度仪研究Fe-13Cr-5Ni马氏体不锈钢在加热过程中的组织转变行为.结果表明,Fe-13Cr-5Ni钢在10℃·s-1的加热速率下,加热至奥氏体单相区,冷却至室温后具有明显的“组织遗传”现象.奥氏体以“针状”形式在马氏体板条界处形核并沿着马氏体板条界长大,与母相间保持Kurdjumov-Sachs(K-S)位向关系.加热至两相区不同温度然后淬火至室温,奥氏体的量随两相区保温温度的升高先增加再减少,650℃时对应室温下残余奥氏体的极大值,并且这一变化趋势与试样显微硬度测试结果所得结论一致.  相似文献   

8.
Fe—Cr—Ni—Mn—Si不锈铁基合金的形状记忆效应   总被引:2,自引:0,他引:2  
利用热膨胀仪、光学金相和透射电子显微镜、X射线衍射仪等测试方法研究了Fe-Cr-Ni-Mn-Si不锈铁基合金的形状记忆效应,探索了形变量、形变温度和热处理工艺等因素对其形状记忆效应的影响规律、并对不锈铁基合金的形状记忆机理进行了初步探讨。试验结果表明,经1050℃固溶处理,室温拉伸形变在2%(或弯曲角在120°)以内,于350℃回复后,可获得较好的形状记忆效应。其形状记忆效应来源于形变时产生的大量  相似文献   

9.
为了研究激光熔覆机械轴的耐磨损性能在不同温度下的变化,特选取热处理方式对激光熔覆GCr15机械轴承进行处理和分析,并在25℃的室温和500℃的高温环境下测试其耐磨损性能。结果表示:随着将热温度处理的温度从300℃提升到900℃时,机械轴承无论是在室温还是在高温状态下其耐磨损性能均是先提高再下降;且在675℃时的热处理时,机械轴承在室温和高温磨损的体积分别较300℃的热处理减小68%和74%。因此激光熔覆GCr15机械轴承的热处理温度优选为675℃。  相似文献   

10.
头脑体操2     
1.一支不准确的温度计,把它放在冰水(0℃)中,其指示温度为1℃,把它放在沸水(100℃)中,它的指示温度为107℃,用它测量现在的室温是27.5℃,你知道真正的室温是多少吗?  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.
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   

14.
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   

15.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

16.
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   

17.
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   

18.
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   

19.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

20.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

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