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71.
通过对出土实物的观察和做模拟实验的发现,笔者认为,商周青铜器的纹饰技术伴随其范铸分型技术的进步而不断发展,同时它也引起铭文技术随之变化。商周青铜器纹饰技术具体的发展脉络为:夏代青铜器制模、制范技术不规范,纹饰技术处于摸索阶段。商早期青铜器范铸分型技术已具成熟的工艺设计思想,在素范面压塑纹饰的"纹饰压塑技术"出现;商中期青铜器纹饰技术有了划时代的进步,出现了"纹饰堆塑技术",且与"纹饰压塑技术"兼容并用;商晚期青铜器纹饰技术达到顶峰。西周青铜器范铸分型技术无明显进步,纹饰制作技术显示退化趋势;春秋中期以后,青铜器范铸工艺分型增多,纹饰技术发生改革,发明了单元纹饰范拚兑技术。  相似文献   
72.
日本的产业技术扶持政策与实施手段 以太阳能产业为例   总被引:1,自引:0,他引:1  
日本经济的核心是日本企业以持续技术革新为基础的国际竞争力。日本企业之所以能持续进行技术革新是与日本政府的政策引导和支持分不开的。本文指出日本政府在国家总体目标之下,利用自身的信息优势和资源优势,根据时代的变迁,制定不同的产业技术政策,通过政策引导,使企业能够明确技术革新的方向,并通过对市场的增进为新技术提供需求,从而促进新兴产业的发展。  相似文献   
73.
The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.  相似文献   
74.
运用科学技术方法对清代珐琅的研究   总被引:4,自引:0,他引:4  
作者运用原子发射光谱、扫描电子显微镜、偏光显微镜和金相显微镜,对故宫博物院藏清代珐琅残片进行了实验分析。研究中.对构成珐琅的硅酸盐材料、铜材料、焊接材料以及镀金层的元素组成进行了测试;对珐琅残片断面的焊接层和镀金层的微观形貌、焊接层的金相组织进行了观察和鉴别。在此基础上,运用结晶学、矿物学、金属学和金相学的基础理论对珐琅原料种类、各种原料的作用、珐琅料的熔制与烧蓝、铜材料与焊接材料的合金属性、焊层的金相组织、掐丝珐琅的烧制工艺等问题加以探讨,试图藉现代科技手段揭示清代珐琅所包含的科学技术内涵。  相似文献   
75.
This paper explores the materiality of social power relationally through study of social interactions with artifacts. Specifically, it is argued that acquisition of an artifact instantiates social power by imposing interactions on groups taking part in that artifact's life-history activities. We introduce the “performance-preference matrix,” an analytic tool for systematically studying the effects of such acquisition events on activity groups. The use of the performance-preference matrix is illustrated through an example: the acquisition of electric-arc lights for lighthouses in the 19th century. Suggestions are offered for analyzing culture-contact situations and for handling singularized artifacts such as heirlooms and monuments.
William H. WalkerEmail:
  相似文献   
76.
Traditions and transitions in Korean bronze technology   总被引:1,自引:0,他引:1  
Metallurgical examination of Korean bronze artifacts shows that a technical tradition based on casting and use of leaded high-tin alloys was established in Korea at the early stages of bronze use. After the subsequent discovery of quenching methods that suppress formation of the brittle δ phase, new thermo-mechanical techniques were introduced between the 7th and 10th centuries AD. Lead-free alloys were used, and tin contents near that of the peritectic point in the Cu–Sn phase diagram were chosen. Leaded high tin alloys continued in use, but only in cast objects, and with significant composition variation. The unique conditions during the time of innovation suggest that the transition to new metallurgical techniques was gradually achieved through domestic technical innovation inspired by external influences.  相似文献   
77.
The interpretation that a rock has been subjected to cultural utilization is a basic element of hunter-gatherer research. The fracture mechanics of the flaked stone tool production process are well understood and the material residues are routinely identified during fieldwork. Conversely, non-percussion processes such as hot-rock technology, which can result in rock fracture, are less well understood. An experimental study has been developed to examine the fractured gravels observed at a prehistoric site on the Southern Plains (USA). The experiment has sought to determine whether cultural or natural agencies were responsible for the production of the angularly fractured rocks. The positive results of the experiment indicate that not only were humans most likely responsible for the breakages, but also that the fractured rocks often exhibit distinctive morphologies that may be identified during fieldwork. This simple experimental methodology is applicable to other hunter-gatherer sites where the depositional environment is not conducive to the structural preservation of features such as hearths.  相似文献   
78.
毛泽东与中国科学技术的自主研发   总被引:2,自引:0,他引:2  
毛泽东将科学技术视为革命者完成自身历史使命的重要工具,他洞见先进技术在后发国家追赶发达国家中的作用,将大力发展科学技术视为国家的重要职能,在西方国家封锁禁运、苏联毁约的困境下,千方百计引进先进科技并努力促进自主研发,果断地发展高科技产业,提高中华民族的国际地位,为中国进一步发展打下了基础。回顾毛泽东与中国科学技术自主研发的历程,有助于我们深刻认识和实践新形势下中共中央、国务院做出的建设创新型国家的重大战略决策。  相似文献   
79.
20世纪50年代中国在引进基础上的技术创新   总被引:2,自引:0,他引:2  
20世纪50年代中国的技术引进和技术创新活动集中在“一五”时期和“大跃进”时期,虽然这两个时期在引进基础上的创新活动都是在重工业优先发展战略下的体制框架内进行的,但在引进技术的行业构成、规模、项目建设的实施和技术的消化乃至技术创新机制、成效等方面都有所不同。“一五”时期采用了全面、系统、灵活多样的方式和重点攻关,在消化、吸收引进技术方面取得了明显的成效,某些领域实现了技术再造,技术创新能力得到了迅速积累,但从总体上看仍处于对引进技术的翻版、修改阶段。“大跃进”时期的技术创新机制被严重干扰,群众运动代替了深入细致的科学研究,在群众性技术革新运动中引进基础上的创新活动格外活跃,通过技术革新运动学会了自行制造一些成套设备、生产工艺,但并没有从产业部门或行业整体上真正实现引进基础上的再次创新,其整体水平依然停留在对引进技术的“初级模仿”阶段。  相似文献   
80.
利用XRF、金相显微分析等手段对湖北省荆门市境内左冢楚墓群出土的金属器,特别是青铜器进行了测试分析,XRF分析表明该楚墓群出土的青铜器多为铜、锡、铅三元合金,且容器的锡含量低于兵器和工具,而铅含量则相反。金相分析显示左冢楚墓群出士青铜器多为铸造组织,其中3件铸后经过不同程度的加热:而热锻成形的器物有4件,其中有一件在锻后进行了冷加工。结果显示,此批青铜器合金成分比较科学、制作工艺比较先进。  相似文献   
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