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1.
叙述了金属硅研究背景、发展历史,综述了功能梯度材料制备技术的基本原理、特点,简要介绍了国内外近年来金属硅的制备技术,以及其在国内外的研究现状及应用和发展前景.目前,该材料的发展已向半导体材料、化工、光学及生物医学工程等领域发展,将成为21世纪材料科学发展的方向之一.  相似文献   

2.
介绍了工业制备SiC的各种方法和近年来国内外生产SiC的新工艺及机械法制备SiC粉体技术.指出未来工业制备SiC材料的发展应侧重于对传统的Acheson冶炼工艺进行改进;扩大制备SiC材料的新工艺的生产规模;研究发明用廉价原料制备高性能的新型SiC材料的方法以及研究超细粉碎及分级技术制备多种SiC产品等.  相似文献   

3.
SiC材料的工业制备方法及其进展   总被引:4,自引:0,他引:4  
介绍了工业制备SiC的各种方法和近年来国内外生产SiC的新工艺及机械法制备SiC粉体技术。指出未来工业制备SiC材料的发展应侧重于对传统的Acheson冶炼工艺进行改进;扩大制备SiC材料的新工艺的生产规模;研究发明用廉价原料制备高性能的新型SiC材料的方法以及研究超细粉碎及分级技术制备多种SiC产品等。  相似文献   

4.
复合镀是材料表面加工技术之一。由于其众多的特点,近年愈来愈受到人们的重视。参考了国内外有关文献,叙述了复合镀的研究发展、特点、用途、制备方法以及可能的发展方向。可使读者对复合镀技术有较全面地了解。  相似文献   

5.
机械合金法由于其独特的工艺过程,正日益引起广泛注意。通过对采用机械合金法制备的氧化物弥散强化合金、轻金属合金、磁性材料、贮氢材料、过渡金属硅合金等的介绍和讨论,指出了机械合金法的应用范围及开发前景。  相似文献   

6.
环保水性油墨制备技术与应用现状分析   总被引:1,自引:0,他引:1  
研究国内外水性油墨最新制备技术,并重点分析水性油墨在我国的应用现状。通过大量查阅国内外文献资料,归纳整理水性油墨连接料制备技术与改性研究进展,分析水性油墨应用现状,预测未来发展方向和趋势。水性油墨的研究焦点集中在制备性能优良的新型水性连结料树脂,即水性聚丙烯酸酯,水性聚氨酯,以及纳米改性连接料的制备和改性研究。水性油墨在柔印中所占的比例与日俱增,但在凹版塑料薄膜印刷中尚处于起步阶段。国内外关于水性油墨的研发取得了巨大进展,应积极鼓励水性油墨的承印基材从单一的瓦楞纸、纸张向多种非吸收材料发展;印刷方式从水性柔印向水性凹印方向逐渐推广。  相似文献   

7.
采用多层溅射技术制备了不同成分的WSix/Si薄膜,然后利用真空退火形成硅化钨.对用此技术制备的难熔金属硅化物的结构特性、电学特性和氧化特性进行了系统的研究.结果表明这种技术具有以下特点:可以通过控制成分得到不同晶格结构的硅化物薄膜,可在硅衬底上形成浅接触,还可以防止金属钨的氧化.  相似文献   

8.
剩余污泥资源化利用技术研究进展   总被引:1,自引:0,他引:1  
介绍了剩余污泥处理处置的现状,梳理了国内外剩余污泥资源化方法,包括制备建筑材料、能源利用、制备吸附材料、土地利用、制备微生物絮凝剂等技术。在综合了国内外剩余污泥资源化利用技术的基础上,提出了剩余污泥的应用前景。  相似文献   

9.
报道了紫外光(UV)固化在微流控芯片技术中的应用,利用光刻技术可直接在聚合物材料上制作微通道,以减少微流控芯片的研究成本和制作周期。重点介绍了UV固化在微流控芯片发展过程中的光刻、曝光及表面改性等方面的应用及其特点,综述了近些年来UV固化在微流控芯片技术中的国内外研究现状,为微流控芯片的制备、发展及完善提供了一条可行的路径。最后在总结国内外研究现状的基础上展望了UV固化未来的发展趋势。  相似文献   

10.
难熔金属具有熔点高、弹性模量高、良好的塑性和韧性、高温强度高、热膨胀系数小等特点,是改善金属硅化物室温韧性和高温强度的理想选择之一。重点介绍了Mo、Nb两种难熔金属在增韧金属硅化物材料方面的应用及研究进展。  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.
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   

15.
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   

16.
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   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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