共查询到20条相似文献,搜索用时 156 毫秒
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以湖南理工学院应用化学卓越工程培养实践教学改革为例,探索了卓越工程师培养顶岗实习实践教学模式,建立了顶岗实习实践教学基地,构筑了顶岗实习实践教学体系,组建了"双师型教师"顶岗实习实践教学团队。 相似文献
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《山东化工》2018,(20)
针对生物工程专业实践教学存在的问题,结合地方行业产业需求和人才培养目标,修订了人才培养方案,整合了专业课程,优化和重组了实践教学的内容与结构,科学地设置实践项目,把实验、实习、实训和毕业论文(设计)等有机地结合在一起,构建了由专业基础实践教学、专业综合实践教学、课外创新实践教学、应用拓展实践教学形成的四个层次的小杂粮等"生产性"实践教学体系。实施过程中主要体现在教学载体的产品化、实践教学环境的真实化、实践教学人员的工作化、实践教学管理的企业化等方面,使学生从大一到大四能够接受系统的"生产性"实践训练,为他们将来毕业就业提供了实践锻炼的机会和奠定了坚实的基础。 相似文献
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目前黏土钒矿直接酸浸的试验以及基础性研究较少,为了进一步推动此类问题的研究进展,本项研究采用试验结合热力学计算的方法,通过试验得到了最佳浸出剂结果,运用热力学计算诠释了活化浸出钒过程的热力学行为以及其机理,同时进一步分析了不同硫元素的总量对酸浸液中各组分的影响,为从酸浸液中提钒工艺进行了溶液化学分析。结果表明:二氧化锰有能力将低价钒氧化至高价钒,从而提升钒的浸出率,升高温度对浸出率的提高以及二氧化锰的氧化均会造成不利影响,但是会抑制杂质的浸出,对杂质分离起到积极影响。硫酸的用量一方面会影响浸出过程的pH,同时会影响酸浸液中各组分的含量,低硫的酸浸体系与高硫体系中钒的离子形态存在差异。低硫体系中铁杂质的溶解度会小于高硫体系,有利于提钒过程中杂质的分离。通过分析浸出过程中溶液组分的变化,可以为后续提钒工序提供理论依据。 相似文献
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生物降解材料——聚乳酸的直接合成研究(Ⅰ) 总被引:8,自引:1,他引:7
通过直接缩聚法制备聚乳酸 ,在制备中对溶液聚合和本体聚合两种方法进行了研究 ,结果表明 ,采用适宜的工艺条件 ,用直接法能制备出具有生物降解性能的高分子质量聚乳酸。 相似文献
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Paisan Kittisupakorn Pantapong Tangteerasunun Piyanuch Thitiyasook 《Korean Journal of Chemical Engineering》2005,22(6):813-821
This paper describes neural network models for the prediction of the concentration profile of a hydrochloric acid recovery
process consisting of double fixed-bed ion exchange columns. The process is used to remove the Fe2+ and Fe3+ ion from the pickling liquor, resulting in increasing the acid concentration for reusing in the pickling process. Due to
the complexity and highly nonlinearity of the process, the modeling of the process based on the first principle is difficult
and involve too many unknown parameters. Therefore, an attractive alternative technique, neural network modeling, has been
applied to model this system because of its ability to model a complex nonlinear process, even when process understanding
is limited. The process data sets are gathered from a real hydrochloric acid recovery pilot plant and used for neural network
training and validation. Backpropagation and Lenvenberg-Marquardt techniques are used to train various neural network architectures,
and the accuracy of the obtained models have been examined by using test data set. The optimal neural network architectures
of this process can be determined by MSE minimization technique. The simulation results have shown that multilayer feedforward
neural network models with two hidden layers provide sufficiently accurate prediction of the concentration profile of the
process. 相似文献
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铝合金硼酸-硫酸阳极氧化工艺研究 总被引:7,自引:0,他引:7
硼酸-硫酸阳极氧化是取代铬酸阳极氧化的一种薄层阳极氧化新工艺。该工艺在环保上属“清洁工艺”。研究了槽液成分,工艺条件及膜层性能。槽液成分中影响膜层重量的主要是硫酸含量,而硼酸可能主要是影响膜层结构。溶液温度和工作电压的影响都是通过对电流密度的影响而起作用,可用控制电量的方法来控制膜层的厚度。 相似文献
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以磷酸、丁辛醇为原料,在催化剂存在下合成了用途广泛并可作为新型结焦抑制剂中间体的磷酸酯,实现了磷酸的直接酯化。试验结果表明:在磷酸酯的合成中反应温度、时间、催化剂用量、原料配比等因素对合成都有影响。最佳工艺条件为:醇酸物质的量比2.3:1,反应时间4h,反应温度控制在140℃,催化剂加入量为反应物总物质的量数的2.0%,且采用硫酸氢钠-氧化铝复合体系(其中硫酸氢钠含量为75%)效果最好,其产率为75.67%。 相似文献
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高氯酸脱水重量法测定矿石中高含量硅 总被引:2,自引:0,他引:2
阐述了采用“高氯酸脱水重量法”测定矿石中高含量硅基本原理、试验方法和试验步骤,并将动物胶脱水重量法与高氯酸脱水重量法分别测定二氧化硅的结果进行了对照,结论是后者完全可以取代前者。 相似文献
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Chemical absorption/stripping technologies using an amine-based solvent have a lot of advantages for capturing carbon dioxide in post-combustion capture system. However, the higher energy demand for the solvent recovery makes the technology difficult to retrofit to existing plants. To overcome this obstacle, an alternative stripping process using an organic acid was studied to decrease the solubility of carbon dioxide and save the energy demand, but further research is necessary to recover the amine solvent and an organic acid effectively. In this study, a new amine recovery method using an organic acid is proposed and the method suggests a two-step of reaction crystallization process to separate the amine and the acid. This study demonstrates that an amine solvent (monoethanolamine, MEA) and an organic acid (oxalic acid) could be recycled effectively by reaction crystallization experiment. MEA and oxalic acid recovery efficiencies were also obtained using the experimental data in this study. The percentages of MEA recovery and the acid losses were estimated through these data. In addition, the energy demands for two recovery processes were estimated. 相似文献
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The industrial applications of acidic leaching processes for alumina extraction from coal fly ash (CFA) have been limited due to its excessive usages of acid and fluoride. This limitation can be lifted by calcining the CFA with the concentrated sulfuric acid at high temperature. When CFA was mixed with the concentrated sulfuric acid of same amount and calcined at 300 °C, most of its aluminum components were transformed into aluminum sulfate. Excessive sulfuric acid was recycled by collecting sulfur trioxide produced during heating process. Morphological and X-ray diffraction evidence indicated that mullite inside CFA was thermally decomposed. Alumina and mullite were transformed into aluminum sulfate. A practical process of alumina extraction from CFA was developed based on this observation. The adoption of calcination process significantly reduced the sulfuric acid usage, shortened the process cycle, and eliminated the use of fluoride. The alumina extraction efficiency was improved up to 85%. 相似文献