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1.
对含砷难浸金矿石的预处理技术及相关试验研究进行了分析 ,并在技术、经济、环保等方面展望了含砷难浸金矿石预处理技术发展的前景 .  相似文献   

2.
黄金资源的利用与提金方法工艺的合理选择   总被引:1,自引:0,他引:1  
论述了黄金资源类型和利用,评述了易浸金矿和难浸矿提全方法工艺的合理选择。引文91种。  相似文献   

3.
本实验考察了微波对低品位难选氧化铜矿氨浸的影响,结果表明,微波对铜矿氨浸具有明显的催化作用,与非微波条件氨浸相比,浸出率能提高31%.  相似文献   

4.
“赋、比、兴”从诗“六义”中分化出来以后,“兴”之义最难定。难就难在概念归属没有定准。把“兴”释为与“比”同类的修辞概念,亦将导致“兴”的浸微浸灭。笔者认为:从“兴”的生成过程,意与象的关系及在创作中的功能几方面看,应把“兴”界定为美学概念。  相似文献   

5.
采用常压烧结在1 700℃下制备出质量分数范围为0~40%的SiC/C(石墨)复相陶瓷材料,对烧结的基体进行浸渗和二次烧结处理,测试了浸渗/二次烧结前后的力学性能、物相组成,并观察了显微结构,对比浸渗和二次烧结等工艺对材料性能的影响。结果表明:浸渗/二次烧结处理能大大降低复合材料的气孔率,提高其强度和硬度。1 700℃烧结后,20%石墨质量分数的SiC/C复合材料试样经过浸渗处理,显气孔率约从32%降低到25%,抗弯强度从46 MPa提高到89 MPa,复合材料的维氏硬度从285 MPa增加到470 MPa。  相似文献   

6.
通过对铧厂沟金矿床金矿石和蚀变细碧岩矿物组成、微量元素、硫同位素、氢氧同位素、铅同位素及稀土元素地球化学特征地对比分析,得出金矿石对该基性火山岩存在明显的继承性.  相似文献   

7.
钛合金表面热浸铝技术是将预处理过的钛合金零件在熔融铝液中浸没一定的时间,在钛合金表面形成镀层以强化表面的一种表面处理技术。本文综述了钛合金表面热浸铝梯度镀层的微观生长机理和组织成分;镀层对合金硬度、耐磨性及抗高温氧化性的影响以及其他热浸铝工艺。分析了浸镀液的温度、浸镀时间及热扩散温度、时间对镀层组织和性能的影响。提出热浸铝+交变电磁场中凝固新方法的可行性。  相似文献   

8.
耐候钢锈层稳定化的表面处理技术   总被引:2,自引:0,他引:2  
以09CuPCrNi耐候钢为基板,采用周浸腐蚀试验的方法,对研制的锈层稳定化表面处理剂进行了性能试验,结果表明,在3%氯化钠溶液的周浸试验中,经过锈层稳定化处理的耐候钢腐蚀率小于未处理样,经过表面复合处理剂处理的试样,经720小时的试验,腐蚀率基本达到了稳定,而裸样到1486小时尚未稳定,说明锈层稳定化表面处理效果明显。  相似文献   

9.
浸渗技术是将已铸好的带有微小孔穴缺陷的铸件,通过一系列特殊处理,将浸渗剂渗入年缺陷中,经过固化,使浸渗剂与铸件孔穴壁联成一体的方法,从而达到堵漏的目的。本文介绍了该技术的原理,装置和实验方法。  相似文献   

10.
真空浸钙对南果梨采后生理变化的影响   总被引:2,自引:0,他引:2  
研究了南果梨采后经真空浸钙处理后在20℃下的生理变化,结果表明:真空浸钙能抑制南果梨的呼吸作用和乙烯释放量,延缓南果梨硬度下降和果皮叶绿素的降解以及可溶性固形物的上升。  相似文献   

11.
高校文化的内部功能有:(1)影响成员意识和规范成员行为,(2)增强学校凝聚力,(3)调节学校内部的社会关系;外部功能有:(1)利用组织意识指导学校与环境互动,(2)利用高校文化特征树立学校形象,(3)利用特定的高校文化适应环境。高校文化的内容包括:意识体系,制度性规范,行为基本模式,象征性符号和模范人物故事和传说等。高校文化的主要特征应与各校特有专业相联系。高校文化内部传播的目的是维持学校内部统一、实现整体协调和整体运作;外部传播的目的是突出本校的文化个性,给公众留下深刻的识别印象,扩大本校对,公众的影响力。  相似文献   

12.
试析大清律中例的地位和作用   总被引:1,自引:0,他引:1  
清代律例合编的法典编纂形式和“有例不用律”的明确规定,使得清例的法律地位大大提高、律的法律地位大为降低。律例合编一度协调了律例矛盾,例对于律的补充、修改、废止作用也曾适应了统治的需要。但是,由于例多为一人一事而设,为贪官污吏徇私枉法留下了很大的空间,导致吏治腐败,加速了清朝的灭亡。  相似文献   

13.
What should be learned? How should it be organized for teaching? These seemingly simple questions are deceivingly political. Curriculum theorists are preoccupied with the politics of the first question at the expense of the realpolitik of the second. Instructional designers are preoccupied with the realpolitik of the second question at the expense of the politics of the first. I argue that conceptual distances between curriculum theory and instructional design are based on divisions of labour established during the 1960s. After decades of neglect, curriculum theorists, and specifically critical theorists, appear clueless when it comes to curriculum design and the realpolitik of their causes. When it comes to the realpolitik of practice their political causes are formless. Quite the opposite of critical theorists, instructional theorists nearly mastered the realpolitik of form but have no political causes. I argue that, to contradict the status quo of C&;I, curriculum theorists will have to dirty their hands with the realpolitik of form and instructional designers will have to clutter their heads with theory.  相似文献   

14.
文明是劳动的积累和积累的劳动,是人类智慧和汗水的结晶,是人们开创新的历史的既得力量。人类社会的进步取决于人类文明的历史传承与创造,社会个体的价值寓于个体自身在历史发展过程中对人类文明的传承与创造。历史的实现方式在于人们对人类文明的历史传承与创造。英雄人物在历史中的作用取决于其是否融入创造历史的群众运动中去。人类文明的传承与创造是人类历史走向进步的重要基石,也是人类历史得以延续与发展的社会基因。人类文明的历史传承与创造积淀成历史的现实与现实的历史,人类历史的演进与人类文明的传承与创造齐头并进。  相似文献   

15.
It is known by entropy theory that image is a source correlated with a certain characteristic of probability. The entropy rate of the source and ? entropy (rate-distortion function theory) are the information content to identify the characteristics of video images, and hence are essentially related with video image compression. They are fundamental theories of great significance to image compression, though impossible to be directly turned into a compression method. Based on the entropy theory and the image compression theory, by the application of the rate-distortion feature mathematical model and Lagrange multipliers to some theoretical problems in the H.264 standard, this paper presents a new the algorithm model of coding rate-distortion. This model is introduced into complete test on the capability of the test model of JM61e (JUT Test Model). The result shows that the speed of coding increases without significant reduction of the rate-distortion performance of the coder.  相似文献   

16.
全球化是一个以科学技术的进步为基础、以资本的国际流动和世界市场体系的构建为表征的复杂运动。全球化过程客观上蕴涵着一种世界性全方位整合取向。然而,这种一体化运动却遭到了民族国家这种政治结构形式的抵制。因此,全球化过程中的政治文化呈现为明显的民族性碎裂状态。其原因不仅在于政治文化的民族性,同时还在于各种政治体利益的特殊性。全球化进程的不断展开客观上要求把政治文化的民族性置于全球性政治共识的基础上,从而形成一种以全球性共识为基础的多元政治文化格局。  相似文献   

17.
选取“文选学”成立过程当中的关键文学史实作为案例切入,通过系统地分析,如实勾划出六朝隋唐时代文学观念演进的各主要阶段,特别提出中古审美视角转变的三个环节,从而反向论证《文选》和“文选学”正是中古文学观念主要特质的代表。进而将之放在近三百年学术史的坐标上同其它专学的发展作以对比,阐明其美学思想在中国文学史的演进过程中所起的再度深化作用。并在探讨后一子命题的同时,联系传统文献的分类思想,对之进行类型学层面的学术阐释。  相似文献   

18.
介绍了论文提交系统的开发背景、设计和实现的过程.在系统设计部分主要介绍了论文提交的主要流程、功能结构、各级用户及其角色的定义、系统的功能以及后台数据库的设计.在实现部分,主要说明系统的开发环境和开发工具,并给出主要模块的代码.  相似文献   

19.
诗歌意象的组合是诗歌话语的组织。从语言学角度对意象跳跃的成因、定义、存在基础及功能进行分析,诗歌意象出现跳跃是由于话语中缺失某些信息因素之间的确定与被确定关系,而使语义间连贯与衔接的正常状态被破坏而造成,它以话语的语用含义作为它在诗歌中存在的基础,能够起到丰富话语意义的作用。  相似文献   

20.
This paper discusses the most persistent controversial issue that occurred in Western educational philosophy ever since Socrates questioned the Sophists: the role of truth in teaching. Ways of teaching these kinds of controversy issues are briefly considered to isolate their epistemic characteristics, which will enable the interpretation of Plato and Dewey as exemplars of rationalism and empiricism regarding the role of knowledge in the curriculum and thus include their partial truths in the epistemic ethos of teaching. The consideration of pedagogy will then include the partial truths of rationalism and empiricism in the epistemic ethos of teaching by following Kant's 'Concepts without percepts are empty; perceptions without conceptions are blind'.
This claim, however, is narrowed down in two ways compatible with postmodernism and the heavy emphasis on constructionism in faculties of education. After quoting Harry Broudy's statement that the educational epistemic ethos should be domain-specific, guided by the experts' inquiry protocols in each curricular area, it is narrowed down further with Maxine Greene's explication that it should be pluralistic and lesson-specific. This epistemic ethos is not argued as a synthesis but as an aggregate of the partial truths of various epistemologies in the spirit of the postmodern doubt in any one theory of knowledge without throwing out the baby with the dirty bath water.
Finally, the streams of consciousness involved in teaching and learning good knowledge are described phenomenologically to disclose how truth can be disclosed in teaching, thereby grounding propositional knowledge, for example, ontologically in the being of the student and in the being of the world.  相似文献   

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