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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.
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   

3.
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   

4.
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   

5.
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   

6.
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   

7.
在人性的问题上,马克思主义之前的哲学往往用静止的、孤立的、片面的、抽象的、形而上学的思维方法来解读人性.马克思主义哲学以实践为出发点,运用辩证的思维方式,对人性作出了全新的二重性的解读,认为人性是全面的、发展的、辩证的,是矛盾的统一体,是能动与受动、客观与主观、具体与抽象、变与不变的统一,是一个系统的、开放的、复杂的有机整体.  相似文献   

8.
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   

9.
一品名规格条件I北京沈阳天津武汉长沙上海成娜西安白银兰妞广州.曰,朴挂牌26000260的2580026500262的25,502石印02?加O25800,月1,f成交257的256加257002630025?的肠以力舫以冲2650025500自口几n几内内挂称‘168的168的1650016别沁168的1645017加01‘创沁16600下口J、U才、肠月J成文166的164001630016500163的164加17的016右的16200自几1什挂脚6,的72Q0690069的7(期】1即0飞95012的70的,口1,f成交68加‘900680068的69的,1506加069的69的山立,朴挂脚95的9500980097的匀55095509夕00肠阅95的,甲1心宁成交94的9300950096加匀5的95的躺0095的…  相似文献   

10.
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   

11.
以水稻土—地表水铀含量为视角,从水稻土剖面铀含量分布规律、水稻土与下伏岩体稀土元素特征、不同河流不同河段水稻土—地表水—稻米铀含量特征、水稻土与稻米铀含量关系4个方面研究721铀矿区稻米铀含量成因。结果表明,水稻土剖面铀含量从表层至半风化花岗质基岩层呈明显降低的特征,说明水稻土铀含量高的原因不是土壤母质铀含量高;岩石与水稻土稀土元素标准化模式均表现为向右倾斜型,均属轻稀土富集型,轻稀土分馏明显,表明水稻土为还原环境,吸附作用较强;不同河流不同河段水稻土—地表水—稻米铀含量平均值的特性均为上游最低、中游最高、下游次之。铀矿区地表水环境符合铀元素在水稻土中被平衡吸附的动力学条件,有利于铀元素在矿区内河流中游地区的水稻土中沉淀富集;正在采矿区水稻土与稻米铀含量具有高度的空间耦合性,呈指数正相关关系,相关系数0.749。矿区内河流沿岸稻米铀含量的分布特征是由铀元素的迁移途径决定的"采矿活动(铀尾矿露天堆放)→地表水→水稻土"。  相似文献   

12.
煌斑岩与金矿化在时间、空间和成因方面关系密切。选择胶东玲珑矿区煌斑岩及其蚀变岩开展56项元素地球化学研究,结果发现胶东玲珑金矿区煌斑岩在成分上相当于高钾玄武质粗面安山岩,相对中国基性岩富K2O、Fe2O3、P2O5、轻稀土、Th、U、Pb、Be、Sr、Ba、Li、Rb、F、Cr,贫Na2O、Ti2O、CaO、MnO、重稀土、Nb、Ta、Sc、W、Bi、Zn、Cd、As、Co、V、B。玲珑金矿区蚀变煌斑岩相对新鲜煌斑岩贫Na2O,富MnO、Pb、Zn、As、W、Sb、Cd、Au、Ag,这表明引起煌斑岩蚀变的这期热液流体富含W、Pb、Zn、Cd、Au、Ag、As、Sb等热液成矿元素。花岗岩风化指数WIG可较好地适用于煌斑岩蚀变过程的研究,且较蚀变指数CIA在反映蚀变程度上更灵敏。  相似文献   

13.
The authors developed and meta-analytically examined hypotheses designed to test and extend work design theory by integrating motivational, social, and work context characteristics. Results from a summary of 259 studies and 219,625 participants showed that 14 work characteristics explained, on average, 43% of the variance in the 19 worker attitudes and behaviors examined. For example, motivational characteristics explained 25% of the variance in subjective performance, 2% in turnover perceptions, 34% in job satisfaction, 24% in organizational commitment, and 26% in role perception outcomes. Beyond motivational characteristics, social characteristics explained incremental variances of 9% of the variance in subjective performance, 24% in turnover intentions, 17% in job satisfaction, 40% in organizational commitment, and 18% in role perception outcomes. Finally, beyond both motivational and social characteristics, work context characteristics explained incremental variances of 4% in job satisfaction and 16% in stress. The results of this study suggest numerous opportunities for the continued development of work design theory and practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
大多数工业化国家的冷轧电工钢都采用IEC标准制定本国标准,在铁损、磁感相同的情况下,评价标准水平高低和质量优劣的主要指标就是电工钢的尺寸公差。经对IEC、欧洲、日本、中国、美国标准尺寸公差的比较得出:取向钢的同板差,IEC、欧洲、日本、中国相同;美国ASTM标准较严。无取向钢的同板差,美国最大,中国、日本中等,IEC、欧洲最小。取向钢的横向厚度差,IEC、欧洲标准严于日本、中国标准0.010mm;美国ASTM没有规定。无取向钢横向厚度差,IEC、欧洲标准较严,日本、中国较松。美国没有规定。宽度偏差,IEC、欧洲标准最小,美国最大,日本、中国中等。  相似文献   

15.
Animal models are useful in elucidating the neural basis of age-related impairments in cognition. Burke, Wallace, Nematollahi, Uprety, and Barnes (2010) tested young and aged rats in several different protocols to measure object recognition memory and found that object recognition deficits in aged rats were consistent with these rats behaving as if novel objects were familiar, rather than familiar objects being treated as novel (that is, forgotten). A similar pattern of behavior has been observed in young rats with perirhinal cortex lesions. Moreover, age-related impairments in object recognition were uncorrelated with deficits in spatial learning in the water maze, a task that requires the integrity of the hippocampus and is also reliably impaired in aged rats. Taken together, these findings support functional specialization of structures within the medial temporal lobe “memory system,” as well as the independence of age-related deficits in different cognitive domains. They also potentially form a foundation for neurobiological study of age-related impairments in perirhinal cortex function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
To contrast mechanisms of lexical access in production versus comprehension we compared the effects of word frequency (high, low), context (none, low constraint, high constraint), and level of English proficiency (monolingual, Spanish–English bilingual, Dutch–English bilingual) on picture naming, lexical decision, and eye fixation times. Semantic constraint effects were larger in production than in reading. Frequency effects were larger in production than in reading without constraining context but larger in reading than in production with constraining context. Bilingual disadvantages were modulated by frequency in production but not in eye fixation times, were not smaller in low-constraint contexts, and were reduced by high-constraint contexts only in production and only at the lowest level of English proficiency. These results challenge existing accounts of bilingual disadvantages and reveal fundamentally different processes during lexical access across modalities, entailing a primarily semantically driven search in production but a frequency-driven search in comprehension. The apparently more interactive process in production than comprehension could simply reflect a greater number of frequency-sensitive processing stages in production. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

17.
Theoretical models featuring cognitive processes have played a fundamental role in advancing knowledge of psychopathology and its treatment and have emphasized the importance of cognition in psychotherapy. Recognition of the importance of cognition in psychotherapy has led to a number of questions that are addressed by the articles in this special section of the Journal of Consulting and Clinical Psychology. Cognitive therapy is well represented in the articles in this special section, but therapeutic procedures that do not represent typical cognitive therapy are also examined. The articles in this special section focus on homework in the modification of cognition, cognition in the treatment of anxiety in adults and in children, change in depressive cognitions in children, cognition and rapid change in the treatment of depression, and the role of cognition in the treatment and prevention of depression that is recurrent. Examination of these types of questions holds the possibility of advances in existing treatments and the possibility of innovations in new treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
评述近年来国内外金属矿业粉碎工程领域的几个热点问题,内容涉及圆锥破碎机、辊压机(高压辊磨机)、自磨(半自磨)机、球磨机、再磨搅拌磨机等。介绍和评述了目前国际上最先进、最著名和最大规格的粉碎工程设备之最新发展,例如瑞典Sandvik集团的CH系列液压圆锥破碎机、芬兰Metso集团的HP系列圆锥破碎机、我国与俄罗斯的惯性圆锥破碎机,德国ThyssenKrupp Polysius公司和KHD Humboldt Wedag公司的辊压机、我国中信重机公司的自磨(半自磨)机和球磨机、现代自磨(半自磨)实验技术、澳大利亚Mount Isa铅锌矿和德国Netzsch-Fein-mahltechnik公司的Isa搅拌磨机、芬兰Metso集团的VertiMill搅拌磨机等。  相似文献   

19.
介绍了湘钢在调整煤源结构、优化炼焦煤质量管理方面所做的一些工作。近年来 ,湘钢依靠科技进步 ,坚持精料方针 ,不断强化企业管理 ,使焦炭质量有了较大的提高 ,为降低高炉焦比 ,提高高炉的利用系数做出了应有的贡献  相似文献   

20.
To examine the associations between changes in cognitions and coping and multidisciplinary pain treatment outcomes, the authors had 141 patients with chronic pain complete measures of adjustment, beliefs, catastrophizing, and coping; in addition, their significant others rated patient physical functioning at pretreatment, posttreatment, and 6- and 12-month follow-ups. Decreases in guarding and resting and in the belief that pain signals damage were associated with decreases in patient disability. Increases in perceived control over pain and decreases in catastrophizing and in the belief that one is disabled were associated with decreases in self-reported patient disability, pain intensity, and depression. The results are consistent with the hypothesis, derived from cognitive-behavioral models of chronic pain, that the outcomes of multidisciplinary pain treatment are associated with changes in patient cognitions and coping responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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