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41.
我国人世一年来轮胎行业的经济运行情况良好,主要经济指标均达到了两位数的增长。轮胎行业的发展投资空前活跃,国有、民营、外资和台资控股企业都加大了对高端产品生产能力的投入。人世对我国轮胎行业的冲击没有想象的大,而且其正面效应也已逐步凸显。为了更好地适应发展的要求,我国轮胎企业还要进行更深层次的改革和认真调整战略定位。 相似文献
42.
“入世”后,在5年内我国PVC糊树脂将从现实实施税率16%降到6.5%。这会给国内PVC糊树脂行业带来一些影响,多方面挤压国内PVC糊树脂的生存空间。因此,熟悉、运用世贸组织的有关规则,加快科技进步,调整产品结构,调整产品结构,转变经营观念,努力开拓、占领市场,是国内PVC糊树脂“入世”的重要措施。 相似文献
43.
熊建军 《福建建筑高等专科学校学报》2010,(4):419-423
从实践来看,WTO成员方认可《TRIPs协议修正案》还存在着一定的法律障碍。WTO成员方可适用TRIPs协议而不适用《TRIPs协议修正案》就可达到一定的目的。WTO成员方愿意援引TRIPs协议强制许可条款而不愿意认可《TRIPs协议修正案》有一定的理由。 相似文献
44.
镁/镁合金焊接与加工的最新进展与未来展望
Sachin Kumar,武传松
(山东大学 材料科学与工程学院,济南 250061)
中文说明:
该文非常详细地综述了镁及镁合金的生产、加工及焊接的研究现状。尤其是在镁合金焊接部分,作者比较详细地阐述了熔化焊、激光焊、固相焊及钎焊等方法在镁合金焊接中的研究现状、存在问题与发展动向。该文对于镁合金焊接研究人员具有重要的参考价值。
关键词:镁;镁合金;加工;焊接;连接;最新进展
相似文献45.
Ambreen Nisar Tyler Dolmetsch Tanaji Paul Cheng Zhang Benjamin Boesl Arvind Agarwal 《Journal of the American Ceramic Society》2021,104(6):2483-2494
The application of ultra-high-temperature ceramics (UHTCs) demands effective ways of joining in overcoming the problems associated with the fabrication of complex-shaped components. In this study, we choose to investigate a new method of rapidly joining pre-sintered TaC and HfC ceramics without any filler material using the spark plasma sintering (SPS) technique. A well-bonded TaC–HfC interface was observed with no apparent cracking and porosity at the joint. The joining mechanisms were predominantly driven by solid-state diffusion and localized plastic deformation. The nanomechanical properties of the TaC-HfC joint are better than the HfC while comparable to that of the TaC. High-load indentation (up to 200 N) results suggest that the TaC–HfC interface is stronger than the parent UHTCs with no crack propagating at the interface. Upon comparison with the parent UHTCs, the damaged area and the average crack length at the interface, reduced up to ~94% and ~56%, respectively. This study shows that the SPS technique can also apply to joining other UHTCs without any filler, resulting in the new field of developing complex components for the thermal protection system (TPS). 相似文献
46.
M. Kiuchi J. Yanagimoto S. Sugiyama 《Journal of Materials Processing Technology》2003,140(1-3):163-166
A process to join glass or stone onto base metal alloys is proposed. The process characteristics allow using various kinds of glasses or stones, such as craft glass, beads, tile, amethyst, agate and hematite with different shapes and sizes. The process utilizes excellent and active join ability of mushy or semi-solid alloy’s properties. In this study, the mechanism of the joining was investigated and some applications were showed. The process itself has several useful properties like: (1) easy-to-operate, (2) ability to get good joining condition, and (3) applicability to a continuous production system. Through the study, it is found that the mushy joining is a useful and valuable manufacturing method for developing and manufacturing glass/metal or stone/metal composites. The mushy joining process is different from the existing cloisonné and enameling process. 相似文献
47.
研究了活性填料纳米Ni粉对陶瓷先驱体聚硅氮烷连接反应烧结SiC陶瓷接头性能的影响,同时与惰性填料纳米SiC粉及活性填料微米Ni粉进行了对比,指出填料的种类及颗粒度对连接强度均有较大影响。活性填料纳米Ni粉的加入可减少连接层内的孔隙和裂纹,同时还可以与聚硅氮烷的裂解产物及母材发生反应,促进聚硅氮烷的裂解,从而降低连接温度,提高连接强度。当连接温度为1200℃时,其最大抗弯强度达到251.6MPa。微观研究表明,连接层结构较为均匀致密,且与母材间界面结合良好。惰性填料纳米SiC粉对连接强度没有明显改善。微米Ni粉因不能与先驱体形成均匀的连接层而导致连接强度降低。 相似文献
48.
加入WTO给当代大学生带来的若干思考 总被引:3,自引:0,他引:3
入世对大学人才培养目标、社会人才需求、大学生知识结构、学习理念、就业市场等提出了新的要求,当代大学生必须提高自身的综合素质,培养创新能力,开阔国际视野,重视非智力因素的培养等,以此来适应WTO对人才的需求。 相似文献
49.
1 INTRODUCTIONAseveryoneknows ,aluminumandstainlesssteelaredifficulttoweldtogether[16 ] .Inthepast,braz ing ,projectionweldingaswellasaluminizingwereused .Nowadays ,anewmethodisputforward ,inwhichthealuminumsheetandstainlesssteelsheetheatedbyinductionheaterareconnectedbypressureofascrew press .Notonlycanthismethodimprovebondingbehaviorofthecompositesheet,butalsocanitraisetheproductivity greatly .Thistechnologyiscalleddeformationjoining ,i.e .pressjoining .InChi na ,ithasbeensuccessfully… 相似文献
50.
Jae Sundaram 《Information & Communications Technology Law》2015,24(2):121-163
The entry of the Trade-Related Aspects of Intellectual Property Rights (TRIPS) Agreement has seen the developing countries and the least developed countries (LDCs) suffer from the excessive burden of obligations imposed under the Agreement to embrace and implement a higher standard of intellectual property (IP) protection. One of the areas where the impact of the measures is most felt is on accessibility to affordable medicines for frontline treatment of diseases in developing countries and LDCs, where the majority of the HIV/AIDS sufferers come from. This inevitable plight, although well known, and posited by the developing countries and LDCs during the Uruguay round of negotiations, was overlooked. This also necessitated the Doha Deceleration, which does not seem to have addressed the problem. The developed countries have also successfully utilised the TRIPS Agreement's IP rights protection criteria as a benchmark, to develop a much higher IP rights protection agenda through the introduction of TRIPS-plus provisions in bilateral and other multilateral agreements entered into with developing countries. The winners in the game are the patent-holding pharmaceutical corporations, software corporations, media corporations, and the developed countries where they are incorporated. The ones at the receiving end are the developing countries and the LDCs who were promised technology transfer to build a modern economy by the developed countries, but are faced with multiple problems of non-availability of affordable medicines for health care, besides others. This article seeks to study the justification for an extended IP rights protection under the TRIPS Agreement through an analysis of the philosophical underpinnings of the IP rights and the patent regime. It will be argued that the TRIPS Agreement is a major obstacle that the developing countries and the LDCs have been made to face as Members of the WTO (World Trade Organisation), with no end in sight for their miseries, and that the only possible solution is a review or an amendment of the TRIPS Agreement. 相似文献