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1.
研究了用Sol-Gel法制备粉料和气氛烧结KTN陶瓷的优化工艺,通过分析烧结气氛和烧结条件的KTN陶瓷性能的影响,指出相应的最佳烧结温度为1200℃,保温时间为87h。  相似文献   

2.
高取向KTN薄膜的PLD法制备研究   总被引:4,自引:1,他引:3  
用Sol-Gel法自制了KTN陶瓷,以之为靶材,首次在单晶硅上用PLD技术沉积了KTN薄膜。  相似文献   

3.
采用 Na Cl K Cl熔盐法制备了单一钙钛矿相结构的 08 P M N02 P T 陶瓷样品,研究了烧结温度和烧结时间对其显微结构和介电性能的影响.结果表明,烧结温度对陶瓷的显微结构和介电性能影响非常显著, 其最佳烧结温度、时间分别为1 200℃,30 m in.  相似文献   

4.
采用aCI-KCL熔盐法制备了单一钙钛矿相结构的0.8PMN-0.2PT陶瓷样品,研究了烧温度和烧结时间对其显微结构和介电性能的影响。结果表明,烧结温度对陶瓷的显微结构和介电性能影响非常显著,其最佳烧结温度、时间分为1200℃,30min。  相似文献   

5.
KTa0.4Nb0.6O3铁电陶瓷固相反应中红外吸收光谱的研究   总被引:3,自引:0,他引:3  
利用红外吸收光谱分析方法,研究固溶体钽铌酸钾铁电陶瓷原料在预烧阶段中的固相反应,观察KTN材料的中心离子与氧离子键的特征吸收峰的生成过程,判断固相反应完成的程度,确定KTN陶瓷的预烧温度,与X射线衍射结构分析和预烧温度对瓷体密度的影响结果比较,发现红外吸收光谱分析方法是确定铁电陶瓷预烧温度的别一种可靠方法。  相似文献   

6.
用Sol-Gel法自制了KTN陶瓷,以之为靶材,首次在单晶硅上用PLD技术沉积了KTN薄膜,并对所制备的薄膜进行了XRD和SEM分析及P-E电滞回线观察.观察分析结果表明:薄膜的主晶相为钙钛矿相(约98%),且沿(100)方向取向生长;薄膜表面光滑、无裂纹、致密性好;薄膜具有良好的铁电性质.同时还分析了Si(100)单晶衬底上钙钛矿相的形成机理;并讨论了衬底温度Ts和氧气氛等因素对成膜的影响.  相似文献   

7.
蘑芋精粉对小鼠免疫器官和细胞因子水平的影响   总被引:7,自引:0,他引:7  
AKP(AmorphophaluskonjacKKohnPowder)具有明显促进小鼠免疫功能的作用,对胸腺指数和脾指数具有增高作用.将小鼠MΦ用LPS(10μg/mL)孵育18~24h后,培养上清IL1和TNFα水平均随AKP浓度的增加而增加,表明LBP2对MΦ合成和释放IL1、TNFα具明显促进作用.此外,AKP对小鼠血清中TNFα水平也有一定的促进作用.  相似文献   

8.
低温烧结PZT压电陶瓷的研究   总被引:7,自引:0,他引:7  
对PZT压电陶瓷的低温烧结进行了研究。实验发现,在PZT陶瓷中添加少量低 熔玻璃(xB2O3-чBi2O3-zCdO)可使烧结温度从1250℃降低至960℃。其性能参数: Kp≥0.52~0.56,Qm≥1000,ε33T/ε0=800~1200, tgδ≤5×10-3.借助于扫描电镜 (SEM)、电子探针微区分析(EPMA)、X光光电子能谱分析(XPS)和体积烧缩速率的 测量,对陶瓷显微结构、烧结机理和添加剂的作用进行了讨论,所研制的低温烧结瓷料 巳用于制备独石压电陶瓷变压器,其空载交流升压比可高达 9 000以上。  相似文献   

9.
碳化硅、氧化锆增韧氧化铝复相陶瓷的研究   总被引:6,自引:0,他引:6  
在纳米氧铝粉中加入碳化硅晶须和纳米氧化铝粉,通过烧结得到细晶的氧化铝基复相陶瓷,达到了提高氧化铝陶瓷断裂韧性的目的.研究了Nano-Al2O3/SiC(w)、ZrO2复相陶瓷的烧结温度、晶粒尺寸、SiC(w)含量等对细晶Al2O3基复相陶瓷材料断裂韧性的影响.采用纳米Al2O3粉,可使烧结温度大幅度下降,在1600℃即可得到致密的细晶陶瓷材料.SiC(w)质量分数w为18%时可以得到较高的断裂韧性值,KIC=6.96MPa·m1/2.晶须增韧的机理仍然是晶须的拔出和断裂.加入ZrO2后,利用ZrO2的相变增韧的效果,可以使Al2O3基陶瓷材料的断裂韧性进一步提高.  相似文献   

10.
讨论含K2O的α-Fe2O3材料中,添加丝光沸石对材料湿敏性能的影响.结果表明添加丝光沸石,抑制了α-Fe2O3晶粒生长;材料中孔大小和分布得到改善,消除了样品在烧结过程中生成的使材料不稳定的β-K2O和KFe11O17相.因而氧化铁-丝光沸石-氧化钾系陶瓷具有优良的湿敏特性和稳定性  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.
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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