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分析了目前低温液体充装系统发生事故的原因 ,指出根据汽化器出口温度、压力报警与泵电机联锁设计及泵的排量、汽化器、汽化量、充瓶数之间的关系设计 ,是保证充装系统安全的有效措施。 相似文献
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设计了基于单侧溢流式恒温水浴系统的快速热平衡式pVTt气体流量标准装置,对水浴及临界流喷嘴进行了实验研究,采用了五路阀门组合控制技术,实现了预抽气功能,降低了压力波动.装置平衡时间为6 min,与其它pVTt法气体流量标准装置相比,平衡时间至少缩短一倍. 相似文献
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低温贮罐自增压汽化器的设计计算 总被引:6,自引:0,他引:6
讨论了低温液体贮槽自增压汽化器的有关设计问题,给出了液体耗量、吸热量、对流换热系数及换热面积的计算公式,并以实例加以说明。图2。 相似文献
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一、强制性产品认证制度简介强制性产品认证制度,是各国政府为保护广大消费者人身和动植物生命安全,保护环境、保护国家安全,依照法律法规实施的一种产品合格评定制度,它要求产品必须符合国家标准和技术法规。强制性产品认证, 相似文献
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It is shown that user-oriented software plays an important role in the design of sensor systems. Justification is provided for functional modules that make it possible to introduce instrumentation support and application shells into the sphere of metrological practice.Translated from Izmeritel'naya Tekhnika, No. 11, pp. 13–16, November, 1995. 相似文献
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用MOCVD方法生长了n+-InP/n-InP/SI-InP材料,以HfO2为介质膜,用电子束蒸发和选择化学腐蚀研制成栅宽0.002mm、栅长为0.2mm的具有蘑菇状栅极结构的InPMISFET.直流特性测量表明,跨导gm=80-115ms/mm,开启电压VT-3.62V,沟道的有效电子迁移率ueff=674cm2/V·S,界面态密度NSS=9.56×1011cm-2.设计计算的特征频率fT=97.1GHz,最高特征频率fmax=64.7GHz,尚未发现器件性能的漂移现象.本器件可作为InP基的单片光电子集成器件(OEIC)的放大部分. 相似文献
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文章总结了多联式分体空调机的安装工艺,并详细的介绍了试压、抽真空及充冷媒的施工方法和调试、试运转的注意事项等. 相似文献
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Concepts for textile reinforcements for timber structures 总被引:1,自引:0,他引:1
P. Haller 《Materials and Structures》2007,40(1):107-118
This paper presents general remarks on the development of timber structures as a result of technological changes. It discusses
drawbacks of wood with respect to structural application. Shear and transversal strengths are very low due to the anisotropy
of wood. Various techniques are applicable to cope with this drawback. This paper presents the reinforcement by means of tailor
made textiles as comprehensive technology to deal with this kind of difficulties in many design situations. Particular importance
is attached to the material productivity during the transformation of raw wood into structural cross sections. It is shown
that cut offs in the sawmill and the predominating full section lead to a poor use of the material compared to technical profiles.
A new understanding of the wood as a cellular solid is presented that allows a thermo-hygro-mechanical forming of cross sections
from solid wood panels.
Résumé Cet article présente des considérations générales sur l’évolution de constructions en bois en␣relation avec les changements technologiques. Il␣discute les inconvénients de l’utilisation structurale du bois. Vu l’anisotropie du matériau, la résistance au cisaillement et celle perpendiculaire aux fibres sont très faibles. Diverses techniques ont été proposées dans le passé pour pallier ces inconvénients. Les renforcements textiles sur mesure sont présentés comme technologie universelle permettant de surmonter ces difficultés dans la construction. Un accent particulier est mis sur la productivité du matériau à l’égard de la transformation de la grume dans une section portante. Il est démontré que les déchets dans la scierie ainsi que les sections solides mènent à une mauvaise exploitation du matériau bois comparée à celle des profilés métalliques et plastiques. Une nouvelle conception du bois comme solide cellulaire est présentée∼; elle permet un formage thermo-hygro-mécanique des sections tubulaires à partir des panneaux de bois massifs.相似文献
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2007年第8号(总第27号)No.008-2007(No.027intotal)中国标准化协会批准以下标协标准,现予公告。CAS156-2007标准电子签名系统应用规范第1部分:IE应用接口 相似文献
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Conclusion With the research byLong, Allison andMcGinnis, Cole andCole, an-Garfield an initial understanding of the consequences of multiple authorship for empirical studies of science is emerging.9 It is too early to suggest, asLong andMcGinnis do, that indices which disgegard multiple authorship are without serious short-comings. The best advise would be to use measures which take multiple authorship into account, compare them with others that do not, and examine any differences that might emerge. At least for the data will which I have worked, multiple authorship makes a considerable difference. Although little difference is found with the data collected by long and his colleagues when examined within an unclear regression analysis framework, it would seem premature to recommend unadjusted counts. The best advice to the prospective researcher would be to collect complete information on the number of authors for all published work and all citations assuming that difference between adjusted and unadjusted counts will emerge and be comfortable with the knowledge that if it does, the measures used can properly treat the data.The major point I made earlier, that the failure to adjust for multiple authorship is the most serious error in empirical judgment made in the sociology of science, emerges more forcefully. The error will require substantial redevelopment of previous empirical literature constructed with these faulty measures.Finally, the point should not be lost that the most serious problem remains and that is the validity of the paper model of science with examines article and citation counts to understand this complex dynamic project of human inquiry.10 相似文献