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1.
《考工记》中记载的“六齐”是研究商周青铜配方的重要文献资料。牛津大学马克·波拉德和大英博物馆刘睿良从战国钱币成分的研究出发,提出对“六齐”中“金”“锡”含义的新解,即通过混合80%铜-15%锡-5%铅预制三元合金与50%铜-50%铅预制合金得到铸造青铜器所用的合金,其关键假说在于以预制合金作为青铜配方的原料。然而,本文基于对“六齐”现有解读的回顾、青铜中铜锡铅配方原则的认识、冶金史考古证据的梳理和铜铅合金铸造性能的分析,认为他们的假说可能不符合我国古代青铜熔炼的实际情况,商周时期主要以红铜冶炼-青铜熔炼两步法生产青铜。  相似文献   

2.
为配合高性能玻璃纤维研发,研究了不同配方的高温涂层粉的玻璃转变温度,并作为漏板外表面涂层进行了试验和实际使用效果分析。结果表明,在SiO_2/Al_2O_3=0.6,1400℃以上的作业温度下,涂层粉在铂合金表面形成致密的保护层,可抑制铂合金挥发,降低铂合金损耗。  相似文献   

3.
用锌基合金生产铸造艺术品是艺术品生产的一个新领域。本文介绍了锌基合金铸造艺术品用锌合金的配方,合金的性能,石膏型的制造工艺及锌合金的熔炼和浇注工艺。  相似文献   

4.
介绍了采用Ni-Co-Mn合金镀层作为电镀金刚石工具胎体的优越性,推荐了电镀液配方及新方法的具体工艺过程与操作规程。  相似文献   

5.
近日,经化学、材料、化工和固际合作管理领域专家的审核,国际科技合作重点项目计划项目“合作开发耐磨合金长寿命免维护蓄电池”通过验收。该项研究开发出含银耐腐合金的配方及正板栅生产工艺、正极铅膏的配方及合膏、固化和化成工艺。经德国大众实验室和IBR实验室共同检测,其汽车蓄电池的  相似文献   

6.
铸铁热浸镀铝工艺不尽成熟,将球墨铸铁热浸镀铝工艺的镀前处理及浸镀参数选择作为研究重点.分析了热浸镀铝层厚度的控制方法和热浸镀铝层的结构.实验表明,获得高质量球墨铸铁热浸镀铝层的关键是预处理工序、酸碱液配方和助镀剂.球墨铸铁热浸镀铝工艺中,合金层影响最大的因素是浸镀时间和浸镀温度.时间的延长和温度的提高,都会使合金层厚度增加.球墨铸铁与Q235钢相比,球墨铸铁镀层的合金层较薄,且合金层针齿更加连续、致密.  相似文献   

7.
用正交试验法研究了在电镀Fe-P非晶态合金的电解液中分别加入钼酸钠和钨酸钠以制取Fe-Mo-P和Fe-W-P非晶态合金的镀液配方和工艺条件。获得了外观呈银白色、平整光滑的非晶态镀层。比较了镀层硬度和在某些介质中的耐蚀性。  相似文献   

8.
在复合结构坩埚(外层石墨坩埚,内层氧化镁坩埚)中,利用真空感应熔炼法制备了坡莫合金,研究了配方和制备工艺对坡莫合金软磁性能的影响.结果表明,同一熔炼工艺,Fe19.8Ni80.2软磁性能最佳;熔化起始阶段合金的边缘位置比内部中央位置软磁性能好,精炼阶段则相反;随着熔炼时间的增加,同一位置的坡莫合金结构越来越均匀,软磁性能越来越好,最后趋于不变.  相似文献   

9.
详述了二价锡离子稳定剂的筛选方法和过程.将筛选出的最佳抗氧剂 Q 组成配方用于铝及其合金的氧化着色过程.  相似文献   

10.
水轮机耐汽蚀喷焊用合金粉末的研制   总被引:2,自引:0,他引:2  
李丽荣 《青海大学学报》2000,18(2):36-37,40
文中分析了金属材料汽蚀破坏的特点;并阐述了喷烛所用的合金粉末配方的研制及消除网状组织,提高其抗汽蚀、抗泥砂磨损的能力。  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.
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 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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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