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1.
添加L€朌PPC和€柷虻鞍对透明质酸润滑性的影响   总被引:1,自引:0,他引:1  
在透明质酸为主要成分的人工关节润滑剂中添加L?DPPC磷脂和?球蛋白,配制成复合人工滑液,在PVA?H/PVA?H, PVA?H/316L S.S. 2类摩擦副上,利用振子式摩擦仪和M2000型磨损实验机,测定其摩擦学参数.结果表明,与纯粹透明质酸溶液相比,复合人工滑液的润滑性能有显著提高.其润滑机制研究表明,润滑性能的提高可能得益于添加物质在PVA?H材料表面所形成的磷脂双层膜及其良好的边界润滑能力.  相似文献   

2.
在透明质酸为主要成分的人工关节润滑剂中添加Lα-DPPC磷脂和γ-球蛋白,配制成复合人工滑液,在PVA-H/PVA-H,PVA-H/316 L S.S.2类摩擦副上,利用振子式摩擦仪和M2000型磨损实验机,测定其摩擦学参数.结果表明,与纯粹透明质酸溶液相比,复合人工滑液的润滑性能有显著提高.其润滑机制研究表明,润滑性能的提高可能得益于添加物质在PVA-H材料表面所形成的磷脂双层膜及其良好的边界润滑能力.  相似文献   

3.
复合人工滑液的流变性能及润滑机制分析   总被引:4,自引:2,他引:2  
研究以透明质酸为主要成分的人工滑液的流变性质,分析添加β-球蛋白和Lα-DPPC磷脂对人工滑液流变性能和润滑性能的影响,并结合滑液粘弹性质与摩擦副表面理化性质对润滑模式进行了探讨。  相似文献   

4.
透明质酸对人工关节材料的润滑作用   总被引:15,自引:4,他引:11  
配合人工软骨材料的研究,探讨透明质酸(HA)作为摩擦副的人工滑液时的润滑性能。在PVA-H/316L,PVA-H/PVA-H两类摩擦副上,利用锥板式粘度计,改进后的振子式摩擦仪和M2000型磨损试验机,测定了不同质量分数的HA溶液的流变性质、摩擦性能和磨损性能,结果表明,HA溶液一定程度上具有天然滑液的流变性质,并有效地降低了摩擦副的摩擦磨损,其对PVA-H/PVA-H摩擦副润滑作用更佳,且0.7  相似文献   

5.
添加Lα—DPPC和γ—球蛋白对透明质酸润滑性的影响   总被引:6,自引:1,他引:5  
在透明质酸为主要成分的人工关节润滑剂中添加Lα-DPPC磷脂和γ-球蛋白,配制成复合人工滑液,在PVA-H/PVA-H,PVA-H/316L S.S.2类磨擦副上,利用振子式磨擦仪和M2000型磨损实验机,测定其磨擦学参数。结果表明,与纯粹透明质酸溶液相比,复合人工滑液的润滑性能有显著提高,其润滑机制研究表明,润滑性能的提高可能得益于添加物质在PVA-H材料表面所形成的磷脂双层膜及其良好的边界润滑能力。  相似文献   

6.
采用自行研制的往复摩擦磨损试验机,研究了不同成分人工滑液润滑的实验条件下UH-MWPE/Ti6Al4关节材料的生物摩擦学性能,并利用扫描电子显微镜观察其磨损表面形貌.结果表明,不同成分人工滑液润滑条件下的UHMWPE/Ti6Al4摩擦副的摩擦系数以及UHMWPE试样的体积磨损量有明显差异:去离子水润滑性很差,因其润滑的UHMWPE/Ti6Al4V摩擦副的摩擦系数以及UHMWPE试样的体积磨损量都最大;Hank's液的减磨性虽然较好,但是润滑性很差;小牛血清去离子水溶液的浓度在20%~40%(V/V)时,UHMWPE/Ti6Al4V摩擦副的摩擦系数以及UHMWPE试样的体积磨损量都很小.  相似文献   

7.
从理论和实际上论述了摩擦-喷气复合纺纱的加捻过程,并利用电子显微镜和示踪纤维方法对摩擦-喷气复合纱和色芯摩擦纺分别进行了分析和测量,发现摩擦-喷气复合纱的芯纱比包芯摩擦纱的芯纱具有较多的包缠纤维和较高的包缠捻度,表明摩擦-喷气复合纺纱有利于提高成纱强力.  相似文献   

8.
Ni基与Ni-P基含MoS_2复会电刷镀层的减摩特性   总被引:1,自引:0,他引:1  
在“球-盘”试验机上对Ni/MoS2与 Ni-P/MoS2两种复合镀层的摩擦磨损性能进行全面的测试与比较,并对其作用机理进行了分析。试验结果表明,两种复合镀层在油润滑条件下的摩擦系数,一般均可达到 0.05~0.06的水平,而 Ni-P/MoS2的承载能力或磨损寿命要比 Ni/MoS2提高 4~6倍以上。  相似文献   

9.
人工滑液在材料表面成膜的AFM图像分析   总被引:1,自引:0,他引:1  
用原子力显微技术(AFM)观测复合人工滑液在材料表面形成的吸附膜的表面形貌图像,吸附膜上清晰地显示有大量的椭球形分子.该吸附膜的形成可能是复合人工滑液对人工关节材料润滑性能显著提高的一个重要因素.  相似文献   

10.
珊瑚/胶原/rhBMP-2复合人工骨异位诱导成骨的实验研究   总被引:3,自引:1,他引:2  
弥补单纯珊瑚无骨诱导活性,骨修复能力弱等缺陷,给临床提供一种良好的骨移植替代材料。方法;将珊瑚与胶原和rhBMP-复合,制备出珊瑚/胶原/rhBMP-2复合人工骨,将其植入大鼠中肌肉陷窝内,以珊瑚/胶原和有/rhBMP-2复合人工骨植入作对照;取材后通过组织学方法和图像分析评价其骨诱导活性。  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.
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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