在多孔钙磷陶瓷表面浸涂溶胶制备HA涂层

采用有机泡沫浸渍工艺制备了具有高孔隙率的多孔钙磷陶瓷,并以此为基体,采用浸涂溶胶的方法在多孔陶瓷网架结构表面成功制备了HA涂层.扫描电镜(SEM)观察样品的孔隙和表面形貌显示,涂层均匀涂敷在多孔陶瓷孔壁表面,形成的涂层中存在着大量由于水分蒸发形成的缩孔.涂层处理对样品的大孔结构没有明显影响,样品仍保持了较高的孔隙率(82.3%±2.8%).X射线衍射(XRD)分析表明,涂层由较纯的HA组成.经不同温度处理后,HA涂层呈现了不同的结晶状态.500℃处理后得到了结晶程度较低的HA涂层,这种涂层有利于提高多孔陶瓷的表面生物活性.对涂层与基体的界面分析后可得,两者之间为紧密的机械锚合.     

表面涂层对多孔玻璃性能的实验研究

随着科学技术的发展和工业上的需求,多孔材料的研究、制备及应用已有很大的进展和深入。本实验主要研究多孔材料表面涂层方法,使涂层后的材料表面改变微孔直径,亲水性和疏水性及表面强度等性能。学生通过创新实验,了解了多孔玻璃制备技术及表面处理,提高了创新意识和动手能力,为学校培养创新性人才提供了很好的实验平台。     

氯化钠作为造孔剂制备含氯多孔羟基磷灰石实验研究

采用化学沉淀法,制备纳米HA粉体.采用造孔剂法,首次利用Na Cl作造孔剂,将纳米HA粉体和Na Cl颗粒按一定比例混合压制成型,经高温烧结制备出多孔含Na Cl的HA材料.利用XRD、SEM、EDX手段研究多孔HA的组成成分、微观形貌、孔径尺寸及孔隙率.研究结果表明:Na Cl是比较理想的造孔剂材料,可制备孔隙率、孔径尺寸、形貌可控的多孔材料.造孔剂含量为30%,尺寸在160~200目时,造孔效果最好;在烧结温度1200℃烧结时,Na Cl会与HA发生反应,生成Ca5(PO4)3Cl,Ca9.54P5.98O23.58Cl1.6(OH)2.74等新的物相.     

羟基磷灰石／二氧化钛生物复合涂层的制备及性能研究

采用溶胶-凝胶工艺在经过微弧氧化预处理的钛基体表面制备HA/TiO2生物复合涂层,观察了涂层的表面及截面微观形貌,测定涂层的表面成分和涂基结合力,并且进行了体外溶解性实验.结果表明:涂层表面涂覆均匀,无明显裂纹;涂层截面层次清晰,涂基结合力较高,可以达到40N左右;涂层在模拟体液中有较好抗体液溶解性和生物相容性,可以提高材料的植入寿命,是一种理想的生物涂层材料.     

聚氨酯多孔涂层制备与表征

利用相转变原理以及湿相浇铸法制备聚氨酯致密和多孔涂层.观察结果表明多孔样品的表面形貌如孔径等主要受质量分数和空气相对湿度的影响.为测试聚氨酯涂层的性能,将样品在Hank's模拟体液中进行浸泡实验,并且对不同样品的亲水/疏水性以及血液相容性进行检测.结果表明在相转变过程中聚氨酯多孔涂层的孔径变化规则有序,并且孔径变化范围为1～30 μm.在Hank's模拟体液中浸泡3个月之后,聚氨酯多孔涂层表面基本没有变化并且涂层没有从基体表面脱落.接触角测量结果表明多孔涂层表面呈强疏水性.此外聚氨酯多孔涂层的血小板粘附量最少,并且延长了抗凝血时间,说明其具有良好的血液相容性.     

低Ca/P比溶液电沉积羟基磷灰石涂层

电沉积羟基磷灰石涂层具有工艺简单、过程易控制、适于在复杂表面制备厚度均匀涂层的特点.沉积液Ca/P比(原子数分数)直接影响涂层中的物相组成与涂层形貌.作者采用电沉积与后续热处理相结合的工艺,用低Ca/P比溶液在金属钛表面沉积羟基磷灰石(HA)涂层.利用X射线衍射、透射电镜和扫描电镜分析了涂层中物相组成及后续热处理对涂层中物相和涂层形貌的影响.实验结果表明电压与电解液温度等工艺参数影响涂层中羟基磷灰石的含量以及沉积过程中晶体长大和形核方式.随电压与温度的升高,涂层中羟基磷灰石含量增加.在低温、高压下,电沉积过程以晶体长大为主,涂层薄而致密;在高温、低压下,电沉积过程以晶体形核为主,涂层厚而疏松.经500 ℃空气中热处理后,涂层基本转化为羟基磷灰石,其Ca/P比约为1.61.电沉积涂层由片状和条状物质组成;热处理后,形貌基本未改变,但颗粒因失水发生团聚.通过精确控制电压与电解液温度等参数,能获取内层致密外层疏松的理想梯度结构HA涂层材料,满足对生物植入体的多种要求.     

(1-x)Li2MnO3·xLiNi1/2Mn1/2O2的低温固相制备及电化学性能研究

采用低热固相法在700 ℃合成了 (1-x)Li2MnO3·xLiNi1/2Mn1/2O2 (x=0.3, 0.5, 0.7)正极材料,并对其相组成、结构、微观形貌进行了表征,对电化学性能进行了测试. 实验结果表明,x=0.7时合成样品中出现尖晶石LiMn2O4相. X=0.3、0.5材料在循环中比容量逐渐升高,后续循环稳定性较好. Fe掺杂加速了x=0.5材料容量的上升,第二次循环时放电比容量高达189.5 mAh/g.     

粉体结构对羟基磷灰石生物涂层组织结构的影响

采用亚音速火焰喷涂方法及涂层处理技术,以Ti6Al4V为基体喷涂不同结构粉体,制备HA生物涂层,并引入Ti/G过渡层缓解应力,涂层经700℃晶化处理.结果表明:粉体结构对HA涂层结构影响较大.化学沉淀法制备的HA粉体,涂层孔洞稀少、致密,喷雾干燥法制备的HA粉体,涂层疏松、多孔.涂层经700℃晶化处理后,主相为晶态HA...     

两步包埋法制备C/C复合材料SiC/Cr-Al-Si涂层研究

采用两步包埋法在碳/碳复合材料表面制备了SiC/Cr-Al-Si涂层.采用XRD、SEM和EDS分析了涂层的物相组成、微观结构及断面元素分布,测试了双涂层碳/碳复合材料试样在1 500℃静态空气中的抗氧化性能.结果表明:SiC/Cr-Al-Si涂层主要由SiC、AlCr2Si及Al4Si2C三相组成,厚度约为120μm,无穿透性裂纹;与一步包埋法所得SiC涂层相比,SiC/Cr-Al-Si涂层碳/碳复合材料试样的抗氧化性能有所提高,该涂层试样氧化12 h后的失重不超过5%.两步包埋法所得SiC/Cr-Al-Si涂层表面存在微裂纹,并且包埋过程易于使Cr-Al-Si合金成分扩散到SiC涂层内部,从而无法形成内SiC涂层、外Cr-Al-Si涂层的双层涂层结构,降低了Cr-Al-Si合金涂层对C/C复合材料基体的高温氧化保护效果.     

基于原子力显微镜的薄膜涂层界面观测及其变形特性

提出了一种基于原子力显微镜的纳米材料弹性模量的测试方法，并应用原子力显微镜对薄膜涂层材料界面微观结构进行高倍观察，定量分析界面相的存在对界面弹性变形的影响.研究结果表明，实验样品为柔性界面；界面相具有晶界型纳米相的微观分布，该微观结构有助于缓解并阻止裂纹的产生，从而增强了纳米涂层材料的承载能力.从微观尺度上探索了界面相效应对材料弹性变形的影响.     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

The Analects and the Moment in Peking——The influence of a Confucian education system on the personality formation,the way of thinking and the fate of the main characters

0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation＇s behavior in their social life throughout the long history is beyond list.