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51.
针对粉煤灰低密度混合材水泥的早强问题展开研究,用实验方法分析探讨了粉煤灰低密度混合材水泥在水化反应过程中的作用机理,开发出了一种高效的能够适用于低温低密度体系的早强剂DY,使得粉煤灰低密度水泥早期强度得到显著的提高。粉煤灰混合材低密度水泥在低温下早期强度的提高,主要通过水泥与粉煤灰之间的相互作用来实现。正反两方面的实验结果表明,水化反应使早期释放更多的Ca2+和OH-,引发了粉煤灰的火山灰反应,从而促进了粉煤灰混合材水泥早期强度的发展。该产品有望在低压井、易漏井、长封固段井等复杂条件下使用。粉煤灰混合材水泥能够满足复杂井固井作业的要求,并且具有可观的经济、环保效益。  相似文献   
52.
In this paper the most relevant findings of our research team on pathological gambling in the last decade are presented. There is no conclusive empirical evidence of a specific profile of the pathological gamblers. The choice treatment appears to be stimulus control and in vivo exposure with response prevention, followed by a cognitive-behavioral intervention in relapse prevention. Predictive variables for the therapeutic failure were the dissatisfaction with the treatment, the alcohol abuse and the neuroticism as a personality variable. Unanswered questions for future research in this field are commented upon.  相似文献   
53.
党的十九大为党和国家各项事业发展提供了理论指南和行动纲领,也为高校招生就业创新发展提供了新的理论指导。在高校招生就业工作中贯彻落实党的十九大精神,需要明晰历史变革、理论创新、事业发展三个维度下高校招生就业条件的变化,以进一步明确新时代高校招生就业的历史方位;需要厘清高校招生就业反映出来的根本问题、重点问题、主要问题、基本问题,不断认清新时代高校招生就业面临的时代问题。在新时代背景下,坚持以习近平新时代中国特色社会主义思想为指导,融合高校思想政治教育发展,丰富多学科视角下的理论体系,推动新理念新技术应用,激活工作端口的延伸性,提升打造工作队伍,是当前高校招生就业改革和发展的重要路径。  相似文献   
54.
Through Brazilian publication revision on the relations amongst Ergonomics and Design, we observed the tendency towards an approach focusing on product design. However, it is our duty to question which would be the influences of ergonomics in the graphic design. As a methodology, we considered the identification that the practices derived from ergonomics as epistemic system found in the main bibliography related to graphic design.  相似文献   
55.
Operators of machinery classified as Advanced Manufacturing Technology (AMT) are exposed to high levels of workload and fatigue. However, only few studies have been conducted on this topic in Hispanic-American countries workers. Several instruments be used to assess workload and fatigue; however, only few of them have been adapted to Spanish language. This paper reports on the development and validity testing of a survey instrument in Spanish, aiming to subjectively assess workload and fatigue among AMT operators in Mexico. Method: After an exhaustive literature review in search of already available measurement instruments, they were adapted for content and later translated into Spanish; a pilot test was conducted to evaluate validity and reliability; afterwards appropriate modifications were made to the testing instruments. Final version of the instrument was applied to a group of 121 operators of CNC lathes. Reliability was analyzed using KMO and Cronbach alpha indices. Results: For the assessment of workload, both NASA-TLX and ISTAS 21 methods were incorporated to the survey instrument. As for fatigue assessment tools, these were SOFI-S, FAS and OFER questionnaires. Results show KMO value and Cronbach alpha above 0.6.Conclusions. The survey instrument as designed, allows the collection of reliable and valid data regarding workload and fatigue among AMT operators in Mexico.  相似文献   
56.
TiO2作为一种重要的催化剂,在石油化工方面有重要的应用,特别是煤基合成油和超深度脱硫中的优越性受到注目。同时TiO2还是重要的白色颜料,为了提高TiO2的应用性能,对TiO2颗粒进行了SiO2纳米膜的表面包覆改性。采用精确控制pH值的连续法在TiO2颗粒表面包覆了SiO2的纳米层,并进行了TEM、HRTEM、EDS、XPS、ICP和光学性质表征。证明了SiO2在TiO2颗粒表面形成了一层连续的纳米膜,厚度大约为3.5~4.0nm,SiO2凝胶纳米膜比较致密,没有未包膜上的絮状物,而且TiO2是单颗粒分散,没有发生多个颗粒被包膜在一起的现象。XPS证明SiO2凝胶在包膜后的TiO2颗粒的表面为物理包覆。用SiO2包膜后,样品的光学性质有了明显的提高,同时改变了样品在不同介质中的分散性质,在水性介质中分散性能提高到93.0%。这种表面处理后的TiO2可以作为一种催化剂用于煤基合成油和超深度脱硫中。  相似文献   
57.
建立科技创新团队是提升企业和高校创新能力的重要途径。从科技创新团队的内涵入手,分析了中国石油和石油高校创新团队建设现状,总结目前校、企科技创新团队建设中存在的问题。认为:校、企共建科技创新团队这一形式是未来发展的方向。结合石油天然气行业的自身特点,阐述了中国石油与高校共建科技创新团队的必要性,提出了从搭建平台、培养领军人物等方面加强科技创新团队建设的发展思路。  相似文献   
58.
为了提高水力喷射压裂中喷嘴的耐蚀耐磨性, 使用普通碳钢进行 PVD 镀膜, 研究了 3 种镀膜试样的表面物理性能和脉冲负偏压的影响, 采用失重法、 电化学法和 XRD 等测试了 PVD 镀膜的耐蚀性。结果表明: 脉冲负偏压在–400∼–700 V, 镀层的沉积速率和显微硬度随负偏压的增大而降低, 膜基结合力先增加后减小; 在高流速下, 3 种试样均表现出良好的耐磨蚀性, 模拟地层水流速为 6 m/s 时, 碳钢的磨蚀速率是镀膜试样的 4 倍; 单因素条件下, 3 种镀膜的腐蚀速率随 Cl−浓度增加先增加后减小, 随 pH 值增加而减小; 3 种镀膜中 AlCrN (厚) 镀膜的耐蚀性最佳, 这与镀膜的致密性和牺牲阳极保护作用有关。  相似文献   
59.
以重庆市3个国家级贫困县万州区、奉节县和巫溪县的农村居民为主要研究对象,采用问卷法和访谈法调查贫困地区农村居民对当前文化建设的满意度及其未来需求状况。研究发现,当前贫困地区农村文化建设处于起步阶段,多元供给机制尚未形成,农村居民对当前文化建设整体满意度较低,尤其是公共文化设施满意度最弱;然而农村居民对未来文化建设的整体需求不足,公共文化服务呈现出明显的低满足、低需求的“双低状态”。对此,本文认为贫困地区农村文化脱贫要以居民精神脱贫为基础,引导居民文化需求层次,辅以差异化供给、多元供给、培养文化建设自生动力,以提升贫困地区农村居民文化建设满意度,满足居民未来文化需求。  相似文献   
60.
The aim of this study was to measure the reliability, validity, and classification accuracy of a Spanish translation of a measure of DSM-IV diagnostic criteria for Pathological Gambling (PG). Participants were 263 male and 23 female patients seeking treatment for PG and a matched non-psychiatric control sample of 259 men and 24 women. A Spanish translation of a 19-item measure of DSM-IV diagnostic criteria for PG (Stinchfield 2003) was administered along with other validity measures. The DSM-IV diagnostic criteria were found to be internally consistent with a coefficient alpha of .95 in the combined sample. Evidence of satisfactory convergent validity included moderate to high correlations with other measures of problem gambling. Using the standard DSM-IV cut-score of five, the ten criteria were found to yield satisfactory classification accuracy results with a high hit rate (.95), high sensitivity (.92), high specificity (.99), low false positive (.01), and low false negative rate (.08). Lowering the cut score to four resulted in modest improvements in classification accuracy and reduced the false negative rate from .08 to .05. The Spanish translation of a measure of DSM-IV diagnostic criteria for PG demonstrated satisfactory psychometric properties and a cut score of four improved diagnostic precision.  相似文献   
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