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1.
高分子材料是我们在生产以及生活的过程中比较常用的一种化学的合成材料,对我们日常的生产以及生活非常重要,起着不可替代的作用,高分子材料一般为人工的制造,传统的制造的模式往往存在着这样或者那样的不足,所以,近些年,我国的许多的科学家通过积极地学习新工艺以及对高分子材料的研究,创造了许多的新的方法,本文主要的讲述基于催化重整脱氯的轴金属高分子材料制备的新工艺的相关的概念。  相似文献   

2.
矿石中含有多种天然物质,矿采对于矿物质的的测定十分重要,有效的开采所需要的矿物质,可以节省大量的人力物力,同时也关系到日后的资金收益。现代社会正处于稳定发展的阶段,所以对矿产的需求比较高,例如电子产业,军事科技等等。有效的利用已开采的矿物质,去除其中的杂质是十分重要的。一块普通的矿石中,往往含有多种杂质,精确的分析其中的化学元素可以更加准确的确定其开采地的矿物质的基本成分。取样是测定的基本前提,铜矿石的元素测定是对矿石本身而言。所以找到有代表性的样品具有重要的意义。本文简述了自然铜矿石的样品加工及其分析的方法。  相似文献   

3.
近年来我国社会的发展过程中,我国的矿产的产值,不断的提升,带来了较大的经济效益,但是随着开采量的不断的增加,给环境带来的污染是不可忽视的。党在十八大提出,要以文明的生态环境,作为宏伟的目标,指出了要将建设生态的文明,放在十分重要的位置上,文章针对矿产资源的开发,地质环境的关系,提出指导性的建议。  相似文献   

4.
整流机组是整流供电的核心设备。对于整流机组而言,合理的方案选择,精良的设计制造,正确的使用操作,以及到位的维护保养是其安全运行的基本保证。方案选择得不合理和设备制造中存在缺陷造成了先天的隐患。不正确的操作和缺乏及时到位的维护会产生后天的祸患。尽可能地排除先天的隐患,避免后天的祸患就是我们要研究的问题和要做的工作。维护检修是其中一项重要的工作。及时到位的维护检修可以发现和排除设备的隐患,保证设备处于良好的状态。即使是很好的设备,缺乏必要的维护保养也是会出问题的。本文重点就供电整流设备的维护和检修问题,结合抚顺铝厂的经验并参照国外公司的产品说明,谈谈个人的粗浅看法。  相似文献   

5.
随着时代和科技的不断进步,数控机床技术的发展不断的优化和完善,整体的数控机床的发展趋势逐步向智能化发展。而对于数控机床的技术的开发和应用也逐渐的受到相关的机床生产商和采购者的重视。因而从实际上来讲数控的智能化发展不仅对机床所加工的产品的质量有一定的影响,对于加工的效率的影响也是比较大的。在此基础上,本文将对数控机床智能化的主要技术特征进行有效的分析和研究,从而使得数控机床技术能够更加健康的发展和进步。  相似文献   

6.
马克思的自然概念是一个具有多重维度的整体性概念.马克思感性的自然概念全面地阐述了人与自然、历史与自然、自然科学与人文科学的辩证统一关系.感性的自然强调的是自然与人的相关性;人化的自然是对人与自然之间认识和实践的对象性关系的概括;历史的自然是对在生产实践基础上历史与自然统一的关系的概括;人本学的自然是对自然科学与人文科学的辩证统一关系的说明;价值的自然是对人与自然之间存在着满足与被满足、需要与被需要的价值关系的概括.马克思的感性自然概念对于理解与建设生态文明具有多方面的启示.  相似文献   

7.
本文从实际操作的层面探讨了环境艺术中重要的一个环节水景的设计工作.丈中已经充分的说明了水景设计是我们人类在生存的地表与其他的一些因素的构成关系所推行的整体性的研判,从这里面找寻出我们人类与大自然和谐共处的发展模式,减少我们人类的行为对于环境的种种破坏,让我们的生态环境能够得到及时的改善,加强我们人类的文明价值,实现人与自然的和平相处.  相似文献   

8.
单位:无/呜品名规格条件北京沈旧天冲武汉长沙上海成娜西安白恨兰绷广州..,刁奋挂牌262阅26侧力2630026100268的舫1的27加02盯0025B的259((2S,00价l寸于成交256阅25日的2620026加O2右3的肪侧沁26以均265的256的一。,当5的.目‘的.内n挂牌170的1石9的1630016500171的l钻印1,2的17创均166的16日的1‘,的侧习矛、U孟,弓用J成交166的165的161因1创00166的1‘别沁17侧】01右以均165佣167的1‘别沁创几,心呼挂月‘,的7400胡oo6右的朋的‘6506.50,O的‘,的7的0..的翎二甲护成交朋的,1佣‘以冲65的‘550‘以沁‘侧沁.}I.‘.的f,幼白白吸嘴呼挂脚,…  相似文献   

9.
提高课堂教学的有效性,精心设计生动的、富有情趣吸引力的、形式多样的活动。教学的有效性是教学设计的生命,是学校教学活动的一个基本追求,它直接关系到教学的质量和人才的培养。加强教师自身素质的提高是课堂教学的有效性的重要前提,教师本身的能力高低会直接的影响到课堂教学质量。  相似文献   

10.
对于一般的人们来说,艺术可能就只是单单的意味着"美"或"不美",而这样的答案在研究艺术的领域里是不能作为准确答案的。对于艺术来讲也许没有什么确定的答案,因为它是在随着社会的发展,一直不断地向前发展的。本文旨在对艺术的构成及艺术的相关内容作详细的介绍。关于艺术的问题,我们可以从艺术的作品、艺术家及艺术的接受几个方面来看。当艺术在艺术品中,艺术显现的更多的是它的欣赏性;当艺术在艺术家手中时,艺术显现的则是人的内心思想感情,社会价值;当艺术又在艺术接受中时,更多的则是生活中人们对艺术的看法。当我们真正了解艺术的  相似文献   

11.
张琦  刘帅  徐化岩  孟志权  王刚  许石 《钢铁》2019,54(10):125-133
 能源管控系统是国家工信部推出的节能减排先进适用技术之一,也是企业实现能源精细化管理的重要措施。综述了钢铁企业能源管控系统的现状和存在的问题,并对未来发展进行了展望。针对能源管控系统核心功能展开进一步分析,从基础能源管理到能效分析与评价、能源供需预测与优化分配、多能源介质耦合优化调度及辅助决策,以及碳排放分析等核心功能,旨在推进中国钢铁工业能源管控系统的进一步完善,促进智能化、绿色化发展,更好地发挥能源精细化管理作用,为企业节能减排做出更大贡献。  相似文献   

12.
我国钛及钛合金板材标准化现状   总被引:2,自引:0,他引:2  
主要回顾了我国钛及钛合金板材标准化历程,重点介绍了本世纪钛板材国标体系的重要变化及完善情况,并与国外先进标准进行了对比,提出了进一步完善和发展我国钛板材标准体系的发展思路、改进意见和建议。  相似文献   

13.
This work offers an anthropological analysis of intra-household processes underlying gender- and age-specific differences in individual nutritional and health care allocations and outcomes in particular cultures. Based on recent ethnographic studies in India, Nepal, Madagascar, Mexico, and Peru, correspondences are analyzed between local cultural ("emic") and scientist-policy maker practitioner ("etic") understandings of nutrition, health, and human development, and the relative "values" of females, males, and children of different ages. The data and analyses clarify specific epidemiological and demographic findings on age and gender bias in nutrition and health and highlight the multiple cultural, economic, and biological factors that contribute to gender- or age-based discrimination or neglect. Recent advances in nutrition policy have argued for a broader concept of nutritional security, one that incorporates both food quantity and quality, and of nutrition as "food, health and care" (International Conference on Nutrition, World Declaration and Plan of Action for Nutrition, FAO/WHO, Rome, 1992). These ethnographic findings; lend strong support for such broader nutrition concepts and associated nutrition policies. The studies also suggest ways in which anthropological questions, methods, and data and community-based research can help predict or identify the nutritionally vulnerable within households and help other social and medical scientists design more effective interventions.  相似文献   

14.
为了研究钢铁制造流程耗散结构的本质及其特征,以高炉炼铁区段为对象,研究解析了多工序协同动态运行条件下的耗散结构优化问题.由料场、焦化、烧结、球团、高炉等工序所组成的炼铁区段,不仅是钢铁制造流程中重要的物质/能源转换中心,也是全流程动态有序、协同连续运行的关键和基础环节.炼铁区段的物理本质是铁素物质流在碳素能量流的驱动和...  相似文献   

15.
钢铁工业节能减排的历史重任   总被引:4,自引:1,他引:3  
重点研究了我国钢铁工业节能减排的目标,钢铁工业能耗、污染物排放的现状,我国钢铁工业与国际先进水平的差距及原因,钢铁企业联合重组取得的新进展,主动减排二氧化碳、二氧化硫气体及我国钢铁工业未来的发展方向.  相似文献   

16.
To develop a modern appraisal of growth for Ayrshire, Brown Swiss, and Milking Shorthorn dairy heifers, data on heart girth and height at withers were collected from 1279 Ayrshire heifers (33 herds), 1819 Brown Swiss heifers (46 herds), and 565 Milking Shorthorn heifers (20 herds), ages 1 to 25 mo, in herds located throughout the US. Means and standard deviations were determined for height and heart girth for each month of age. Third-order regressions on age were fitted to the means to describe height and heart girth. Estimated mean height and heart girth at 6, 12, 18, and 24 mo, in centimeters, were for Ayrshire 98.7 and 118.4, 114.4 and 145.9, 122.8 and 163.2, and 127.6 and 176.4; for Brown Swiss 102.6 and 122.3, 199.4 and 151.3, 128.7 and 168.8, and 134.0 and 182.0; and for milking Shorthorn 98.0 and 119.4, 113.6 and 148.6, 122.6 and 166.6, and 127.7 and 179.9, respectively. These data can be useful to evaluate the heifer rearing program with respect to the growth rates of heifers on an individual farm.  相似文献   

17.
Investigated changes in intimate friendship with same- and opposite-sex friends in preadolescence and adolescence, using the Intimacy Scale. Ss were Israeli children from the 5th, 7th, 9th, and 11th grades (60 boys and 60 girls from each grade), who rated their friendship with a same- or opposite-sex best friend. There was a significant age difference in overall intimacy with same-sex friends. Frankness and spontaneity, knowing and sensitivity, attachment, exclusiveness, and giving and sharing were factors that changed with age. Trust and loyalty, and taking and imposing did not. Opposite-sex friendship revealed a significant increase in intimacy with age. Boys and girls did not differ in reported opposite-sex friendship in the 5th and 7th grades, whereas girls in the 9th and 11th grades reported higher intimacy than did boys. This sex-by-age pattern of interaction was particularly evident for attachment and for trust and loyalty. Girls were higher in knowing and sensitivity, giving and sharing, and taking and imposing. The implications for further differentiation among types of peer relations and interrelation of dyadic friendship and cognitive growth are discussed. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
天铁科技成果管理工作实践   总被引:1,自引:0,他引:1  
张辉 《天津冶金》2011,(3):44-46,66
论述了科技成果管理的内容和意义,结合企业实际介绍了天铁科技管理的制度、体系及实施效果。通过科技创新体系和成果管理制度建设,“十一五”期间促进了科技成果的开发和转化,有多个项目分别列人天津市技术创新重点为项目、天津市二十项重点项目,推动了企业持续快速发展。  相似文献   

19.
OBJECTIVES: Three-dimensional echocardiography (3DE) calculates left ventricular volumes (LVV) and ejection fraction (EF) without geometric assumptions, but prolonged analysis time limits its routine use. This study was designed to validate a modified 3DE method for rapid and accurate LVV and EF calculation compared with magnetic resonance imaging (MRI). METHODS: Forty subjects included 15 normal volunteers (group A) and 25 patients with segmental wall motion abnormalities and global hypokinesis caused by ischemic heart disease (group B) who underwent 3DE with precordial rotational acquisition technique (2-degree interval with electrocardiographic and respiratory gating) and MRI at 0.5 T, electrocardiogram (ECG)-triggered multislice multiphase T1-weighted fast field echo. End-diastolic and end-systolic LVV and EF were calculated from both techniques with Simpson's rule by manual endocardial tracing of equidistant parallel left ventricular short-axis slices. Slicing from the 3DE data sets were done by both 2.9-mm slice thickness (method 3DE-A) and by 8 equidistant short-axis slices (method 3DE-B); for MRI analysis, 9-mm slice thickness was used. RESULTS: Analysis time required for manual endocardial tracing of end-diastolic and end-systolic short-axis slices was 10 minutes for the 3DE-B method compared with 40 minutes by the 3DE-A method. For all 40 subjects the mean +/- SD of end-diastolic LVV (mL) were 181 +/- 76, 179 +/- 73, and 182 +/- 76; for end-systolic LVV (mL), 120 +/- 76, 120 +/- 75, and 122 +/- 77; and for EF (%), 39 +/- 18, 38 +/- 18, and 38 +/- 18 for MRI, 3DE-A, and 3DE-B methods, respectively. The differences between 3DE-A and 3DE-B with MRI for calculating end-diastolic and end-systolic LVV and EF were not significant for the whole group of subjects as well as for the subgroups. The 3DE-B method had excellent correlation and close limits of agreement with MRI for calculating end-diastolic and end-systolic LVV and EF: r = 0.98 (-1.3 +/- 26.6), 0.99 (-1.6 +/- 21. 2), and 0.99 (0.2 +/- 5.2), respectively. The correlation between 3DE-A and MRI were r = 0.97, 0.98, and 0.98, and the limits of agreement were -1.4 +/- 36, -0.6 +/- 26, and 0.6 +/- 8 for calculating end-diastolic and end-systolic LVV and EF, respectively. In addition, excellent correlation and close limits of agreement between 3DE-A and 3DE-B with MRI for LVV and EF calculation was also found for the subgroups. Intraobserver and interobserver variability (SEE) of MRI for calculating end-diastolic and end-systolic LVV and EF were 6.3, 4.7, and 2.1; and 13.6, 11.5, and 4.7; respectively, whereas that for 3DE-B were 3.1, 4.4, and 2.2; and 6.2, 3.8, and 3. 6; respectively. Comparable observer variability was also found for the A and B subgroups. CONCLUSIONS: The 3DE-A and 3DE-B methods have excellent correlation and close limits of agreement with MRI for calculating LVV and EF in both normal subjects and cardiac patients. The 3DE-B method by paraplane analysis with 8 equidistant short-axis slices has observer variability similar to MRI and reduces the 3DE analysis time to 10 minutes, therefore offering a rapid, reproducible, and accurate method for LVV and EF calculation.  相似文献   

20.
针对氧化矿矿石储量大、品位低、矿石性质复杂、难以选别的特点,介绍了某复杂难选铅锌氧化矿综合利用项目的工艺方案、主要生产指标,提出了各项节能措施,分析了项目的用能总量及主要用能工序,并对项目的能效水平进行了分析.通过开发和采用效率高、节能效果好的工艺流程、设备,并做好建筑、给排水、供配电、通风除尘等辅助和附属设施的节能,...  相似文献   

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