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1.
《大学计算机基础》是面向非计算机专业学生开设的计算机基础课程,通过本课程的学习,旨在使学生具备使用计算机科学领域的技术和方法,解决本学科科学问题的基本能力。随着物联网、云计算、大数据、人工智能等新兴技术的快速发展,以及学科之间交叉融合的需求不断增大,导致当前《大学计算机基础》的课程内容和教学方法亟需改进。通过深度分析当前大学计算机基础教育存在的问题,并针对这些问题从课程内容、竞赛导向和师资培训等三个方面进行教学新模式的探索。  相似文献   
2.
Recovering alcohols from dilute fermentation broth is an emergent task in bio-fuel production process. Since they are primary planned for fuels, energy required to separate these alcohols should be considered in evaluating the potential of a separation technology. A membrane-based process, pervaporation, is of special interest because of its environmental friendliness and easy integrating character. This review probes into the fundamentals of pervaporation especially in terms of the heat required for evaporation. Meanwhile, the separation data of the most representative alcohol-selective pervaporation membranes reported in the literatures are collected and compared with the vapor–liquid equilibrium curve, which represents the distillation selectivity. They include:inorganic membranes, silicon rubber based membranes, Mixed Matrix Membranes and some other special materials. By doing so, the status of alcohol recovery via pervaporation would be more clear for researchers.For ethanol recovery, it is selectivity rather than flux that is in urgent need of solution. While for butanol recovery,membranes with satisfactory selectivity have been developed, increasing the separation capacity would be more pressing.  相似文献   
3.
Thiamine Deficiency Complex (TDC) is an ongoing problem impacting salmonine health in various waterbodies, including Lake Ontario. The prevalence of TDC has been variable and explanations for differences are limited. In the current study, thiamine concentrations were measured in eggs, liver tissue, and muscle tissue sampled from brown trout (Salmo trutta), Chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), lake trout (Salvelinus namaycush), and steelhead trout (O. mykiss) that were collected from Lake Ontario and its surrounding tributaries. The occurrence of TDC was measured for each species based on TDC-induced offspring mortality rates under laboratory conditions. TDC-induced offspring mortality was observed for all species except brown trout. For affected species, egg free thiamine (Th) was consistently low compared to lake trout collected from Lake Superior that are considered thiamine replete. In addition, species with the lowest percentages of Th in their eggs were the most susceptible to TDC, suggesting that limited thiamine reserves in the form of Th may cause TDC-induced offspring mortality. Lastly, our results show that egg thiamine concentrations have yearly variation and increased for all species throughout the study. Reasons for such variation are undetermined; but, if egg thiamine concentrations continue to increase, the impacts of TDC on these salmonine species may lessen. Future monitoring is needed for determining if thiamine concentrations are increasing and the potential impacts that may have on the entire Lake Ontario fishery.  相似文献   
4.
Perovskite oxides LaCoO_3 prepared by templating, co-precipitation and sol-gel method with different complexants were systematically characterized and its catalytic performances for CO oxidation were investigated. The samples were characterized by X-ray diffraction, thermogravimetry analysis and differential scanning calorimetry, N_2 physisorption, transmission electron microscopy, temperature program reduction of hydrogen, temperature program desorption of oxygen and X-ray photoelectron spectroscopy measurement, results of which show that the properties of LaCoO_3, such as surface morphology, surface area, surface compositions, redox capability, oxygen vacancy, as well as the calcination temperature and formation mechanism, depend intimately on the preparation method. Catalytic tests indicate that the sample prepared by carbon templating method shows the best activity for CO oxidation, with full CO conversion obtained at 135 ℃. In particular, the catalyst can be activated and significant increase of activity can be obtained with the increase of reaction time. The cyclic and longterm stability of catalysts were discussed and compared.  相似文献   
5.
构建高职院校适应市场需求的公共英语教学体系是当前高职教学改革的一项重要工作。本文从调查问卷设计与发放、调查问卷分析以及对教学改革的启示和建议等三方面进行论述,旨在了解市场对高职毕业生英语应用能力的需求。并以此为依据,促进高职英语教学改革。  相似文献   
6.
Although previous research has investigated widespread use of social media, especially Facebook, by youth attending college, the conditions under which these media foster adjustment to college remain unclear. This study tested a model illuminating pathways linking social competence to college adjustment via students’ perceptions about the usefulness of Facebook and ways in which they used the medium. Self-report survey data from 321 college students (M age = 20.09; 58% female; 84% Caucasian) attending a major Midwestern university supported the proposed model, indicating that higher social competence could foster or impede college adjustment, depending upon how it was related to beliefs about the usefulness of different Facebook functions and how these perceptions, in turn, were associated with patterns of Facebook use. Findings underscore the importance of considering connections among personal attributes, perception of media effectiveness, and media behaviors in assessing the implications of social media for users’ psychosocial well-being.  相似文献   
7.
围绕党的十八大精神和《中共中央关于全面深化改革若干重大问题的决定》中提出的"大力促进教育公平,健全家庭经济困难学生资助体系",以社会主义核心价值观为指导,通过对国家助学贷款中大学生诚信缺失现状及原因的分析,借鉴发达国家的有效模式,探讨国家助学贷款中大学生诚信体系建设的新机制、新思路。  相似文献   
8.
《Planning》2015,(3)
为了培养青年医师运用医学科普语言传播医学知识的能力,向社会提供更优质、可及的健康知识,改善医患关系,促进社会和谐;同时出于向社区、媒体推送一批优秀青年医学科普人才的考虑,本文在总结北京协和医院培养青年医务人员医学科普能力经验的基础上,尝试构建一套适合大型公立医院(尤其是教学医院)培养青年医务人员医学科普能力的新模式——“科普训练营”。本文旨在系统介绍该模式的产生背景、实践经验及初期效果,阐释实施后的重要意义,及实施过程中的挑战与应对策略。  相似文献   
9.
This paper uses a mixed-methods approach to examine the relation between online academic disclosure and academic performance. A multi-ethnic sample of college students (N = 261; male = 66; female = 195; M age ≈ 22 years) responded to open-ended questions about their Facebook use. Thematic analysis revealed that over 14% of the Facebook wall posts/status updates (N = 714) contained academic themes; positive states were more frequent than negative and neutral states and students with lower GPAs expressed negative states more often. A path analysis suggested that academic performance may determine college students’ Facebook use, rather than the reverse. Implications for student support services are discussed.  相似文献   
10.
The effects of Sr2+ substitution for Ba2+ on microwave dielectric properties and crystal structure of Ba3-xSrx(VO4)2 (0 ≤ x ≤ 3, BSVO) solid solution were investigated. Such Sr2+ substitution contributes to significant reduction in sintering temperature from 1400 °C to 1150 °C. Both permittivity (r) and quality factor (Q × f) values decreased with increasing x value, which was determined to be related with the descending values of average polarizability and packing fraction, whereas the increase in τf value was explained by the decreased average VO bond length, A-site bond valence. BSVO ceramics possessed encouraging dielectric performances with r = 12.2–15.6 ± 0.1, Q × f = 44,340 - 62,000 ± 800 GHz, and τf = 24.5–64.5 ± 0.2 ppm/°C. Low-temperature sintering was manipulated by adding B2O3 as sintering additive for the representative Sr3V2O8 (SVO) ceramic and only 1 wt.% B2O3 addition successfully contributed to a 21.7% decrease in sintering temperature to 900 °C, showing good chemical compatibility with silver electrodes, which render BSVO series and SVO ceramics potential candidates in multilayer electronic devices fabrication.  相似文献   
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